فهرست مطالب

محیط شناسی - سال چهل و سوم شماره 2 (پیاپی 82، تابستان 1396)

فصلنامه محیط شناسی
سال چهل و سوم شماره 2 (پیاپی 82، تابستان 1396)

  • تاریخ انتشار: 1396/07/26
  • تعداد عناوین: 12
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  • مقاله پژوهشی
  • سحر شیبانی*، بهروز ابول پور، امیر اسکندری صفحات 181-193
    در این مطالعه مدل های ریاضی ارتباط بین متغیرهای فاضلاب ورودی و خروجی تعیین گردید. نتایج آزمون ضریب همبستگی چند متغیره نشان داد که دو متغیر (TSS،TDS) بهترین ارتباط را با COD و EC خروجی دارا می باشد و ضرایب همبستگی ارتباط بین COD با TDS وTSS به ترتیب برابر با 83% و90% می باشد. نتایج روابط خودهمبستگی میانگین متحرک جامع نشان داد گام زمانی یک روز بهترین رابطه را نسبت به سایر مدل ها در تخمین COD دارد. لذا با استفاده از مدل های خطی و غیرخطی و کلاس بندی تغییرات با داده های نرمال و غیرنرمال مقادیر روزانه COD از مقادیر روز قبل TSS و TDS تخمین زده شد. اما ضرایب همبستگی بدست آمده رضایت بخش نبودند. در نهایت از انطباق سیستم های فازی استفاده گردید که مدل شبیه سازی حاصله مطابقت خوبی (76/0=R2) نشان داد. نتایج نشان داد که منحنی تغییرات COD(t) نسبت به TDS(t-1) دارای یک نقطه عطف می باشد که در TDS(t-1) برابر ppm 1746 اتفاق می افتد. در این مقدار TDS توان پالایش زئولیت معادل COD برابر 52 خواهد بود. این نقطه آستانه تاثیرپذیری زئولیت بر تصفیه آب در خصوص COD می باشد. برای مدیریت تصفیه فاضلاب میزان آلاینده های ورودی به ایستگاه و همچنین حجم فاضلاب عبوری از کانال زئولیت باید به طور همزمان کنترل شوند.
    کلیدواژگان: بهینه سازی، زئولیت، شبیه سازی فازی، فاضلاب صنعتی
  • محمدعلی آهنگرنوکلایی، حسین گنجی دوست*، بیتا آیتی صفحات 195-206
    روش های انعقاد الکتریکی و شناورسازی الکتریکی قابلیت کاربرد برای تصفیه فاضلاب صنایع مختلف دارند. با اعمال جریان الکتریکی به الکترود کاتد و آند، با انحلال آند آلومینیومی یا آهنی، مواد منعقدکننده در محل تولید می شود. همچنین الکترولیز آب منجر به تولید گاز هیدروژن شده که حین صعود به سمت بالا موجب شناوری مواد معلق داخل فاضلاب می گردد. در این تحقیق تاثیر پارامترهای کلیدی دانسیته جریان الکتریکی و غلظت اولیه رنگزا در تصفیه رنگزای اسید قرمز 14 به روش انعقاد و شناورسازی الکتریکی بررسی و مقادیر هر یک از این پارامترها از نظر بازده حذف رنگ، میزان مصرف انرژی و انحلال آند بهینه شد. در ادامه عملکرد این سیستم در تصفیه فاضلاب واقعی رنگرزی بررسی گردید. با توجه به نتایج این تحقیق که حذف 99 درصد رنگزا در زمان کمتر از 30 دقیقه، انرژی مخصوص مصرفیkWh/kg Dye Removed 9/1، آند مصرفی kg Fe/kg Dye Removed 95/0 و TSS لجن mg/L 3700 بدست آمد، توانایی روش همزمان انعقاد الکتریکی و شناورسازی الکتریکی در تصفیه فاضلاب های حاوی رنگزا همراه با مصرف کم مواد و انرژی به اثبات رسید که می توان آن را به عنوان گزینه ای مناسب برای جایگزینی با روش های معمول تصفیه به کار برد.
    کلیدواژگان: انحلال آند، حذف رنگزا، دانسیته جریان الکتریکی، غلظت، فاضلاب واقعی
  • سمیه صدر*، مجید افیونی صفحات 207-218
    با توجه به اهمیت استان اصفهان از نظر فعالیتهای کشاورزی و صنعتی، همچنین جمعیت زیاد این استان، این تحقیق با هدف ارزیابی تغییرات مکانی وانادیوم در بخشهایی از اراضی استان اصفهان و همچنین تهیه نقشه آلودگی این عناصر در خاک های این منطقه انجام گرفت. در این تحقیق نمونه های خاک از عمق 0-20 سانتی متری، بر روی یک شبکه منظم با فواصل حدود 4 کیلومتر برداشت شد. موقعی جغرافیایی نمونه و کاربری محل نمونه برداری نیز شناسایی و ثبت گردید. پس از آماده سازی نمونه های خاک در آزمایشگاه، مقدار وانادیوم کل به وسیله دستگاه XRF تعیین گردید. ساختار مکانی متغیر مورد مطالعه به کمک تغییرنما مورد بررسی قرار گرفت. نتایج حاصل بیانگر ساختار قوی در توزیع غلظت وانادیوم در منطقه است. الگوی کروی بهترین مدل برازش داده شده برای این متغیر می باشد. میانیابی در شبکه بندی 1000 ×1000 متر و با حداقل و حداکثر 4 و 30 نقطه به روش کریجینگ نقطه ای، توسط محیط نرم افزارWINGSLIB انجام شد. بر اساس نقشه پراکنش وانادیوم، به نظر می رسد فعالیت های کشاورزی و انتقالهای اتمسفری موثرترین عامل در افزایش غلظت وانادیوم در منطقه به شمار می رود و جهت باد غالب در انتشار وانادیوم در منطقه موثر بوده است.
    کلیدواژگان: اصفهان، زمین آمار، کریجینگ، وانادیم
  • محسن رضایی *، رشید زیوری، جواد اشجاری، عبدالرضا کابلی صفحات 219-231
    در این مقاله خصوصیات شیمیایی منابع آب سازند کربناته خوش ییلاق در استان گلستان مورد مطالعه قرار گرفته است. از نتایج آزمایشات فیزیکی و شیمیایی مربوط به 20 دهنه چشمه استفاده گردیده است. خصوصیات فیزیکی و شیمیایی و یونهای اصلی مورد سنجش قرار گرفته اند. روش های نمودارهای ترکیبی، نمایه های اشباع و آنالیزهای چند متغیره در ارزیابی پارامترهای کیفی استفاده شده است. فراوانی نسبی یون های اصلی Ca2+>Mg2+>Na++K+ و HCO3->Cl->SO42- است. تغییرات TDS و EC به ترتیب 220 الی 706 میلی گرم برلیتر و 151.9 الی 353 میکرومهوس برسانتی متر می باشد. تحلیل خوشه ایبر اساس غلظت یونهای اصلی آب چشمه ها را در 3 گروه متفاوت قرار داد. تحلیل عوامل کنترل کننده کیفیت آب نشان داد عامل اصلی واکنش سنگ-آب است. با توجه به نمودار گیبس انحلال سنگ های کربناته اثر غالب را بر هیدروشیمی آب دارد و هوازدگی سنگ های سیلیکاته نقش به مراتب کم تری را دارد. جنس غالب کانی های تجزیه شده براساس شیمی آب دولومیت می باشد. نمایه های اشباع کلسیت، دولومیت و ژیپس نشان می دهند که آب زیرزمینی به تکامل شیمیایی نرسیده است. واکنش های تبادل یونی هم در جهت مثبت و هم در جهت منفی روی می دهند و فرآیند تبادلات آنیون-کاتیون یک فرآیند مهم ژئوشیمیایی در کنترل شیمی آب منطقه مورد مطالعه است.
    کلیدواژگان: آنالیز چند متغیره، اندیس اشبا، چشمه کربناته، سازند خوش ییلاق، هیدروژئوشیمی
  • سعید مردان *، سعید گیتی پور، محمدعلی عبدلی صفحات 233-250
    در این تحقیق عملکرد فرآیند تثبیت و جامد سازی در حذف آلودگی خاک آلوده به ترکیبات نفتی از طریق سیمان و آهک و خاک رس اصلاح شده (آلی دوست) مورد بررسی قرارگرفته و سعی گشته که بهترین ترکیب در بین نمونه های بررسی شده به ویژه از نظر نشت آلاینده ها تعیین گردد. مطالعات رفتار نشتی آلاینده ها در فرآیند تثبیت و جامدسازی خاک آلوده به ترکیبات نفتی در محل دفع پسماندهای شهرک صنعتی سلفچگان نشان داد که مخلوط خاک آلوده، رس اصلاح شده و سیمان و آهک، سبب تثبیت اکثر آلاینده های موجود در این خاک گردیده است. همچنین نتایج بررسی های انجام شده حکایت از آن داشت که نمونه حاوی 20 درصد سیمان و 30 درصد رس اصلاح شده در زمان گیرایی 28 روز بهترین کارایی را به لحاظ پارامترهای مختلف موثر بر کارایی روش جامد سازی و تثبیت در بین نمونه های مختلف داشته است. علاوه بر این بررسی توام آزمایش اسکن میکروسکوپ الکترونی و آزمایش نشت نشان داد که دو دلیل در افزایش کارایی نمونه های جامد شده موثر بوده است یکی بالا رفتن میزان رس اصلاح شده که سبب افزایش قدرت جذب هیدروکربن های نفتی شده و دیگری کاهش حجم منافذ در ماتریس که سبب کاهش میزان نشت گردیده است.
    کلیدواژگان: آزمایش نشت، تثبیت و جامدسازی، خاک های آلوده نفتی، رس اصلاح شدد، میزان کل هیدروکربن های نفتی، هیدروکربن های آروماتیک چندحلقه ای
  • وحید ندرخانلو، مهدی مظاهری *، جمال محمدولی سامانی صفحات 251-265
    یکی از سدهای بزرگ کشور، سد گتوند علیا در استان خوزستان می باشد. از مهم ترین چالش های ایجاد شده درباره این سد، وجود توده های نمکی در مخزن سد است که پس از آبگیری مستغرق شده و باعث شوری مخزن می شود. این امر در حال حاضر به یکی از مشکلات اساسی مرتبط با این سد در کشور تبدیل شده است. برای حل چالش مذکور راهکارهایی پیشنهاد شده است که از مهم ترین آنها مدیریت کیفی مخزن توسط آبگیری از لایه های مختلف می باشد. برای داشتن شناختی جامع از هیدرودینامیک جریان و شوری مخزن این سد، با توجه به اندازه گیری های صورت گرفته از مقدار شوری در اعماق مختلف و جریان ورودی در زمان های مختلف، شبیه سازی هیدرودینامیک و لایه بندی حرارتی و شوری با استفاده از مدل سازی عددی سه بعدی برای یک دوره دو ساله از ابتدای آبگیری صورت گرفت. با توجه به اینکه، مقدار نرخ انحلال، مهم ترین پارامتری است که در برآوردهای کمی از میزان انحلال نقش دارد، در این تحقیق، مقدار نرخ انحلال سازندهای نمکی، بر اساس لایه بندی شوری درون مخزن سد، واسنجی و صحت سنجی گردید. همچنین امکان پذیری مدیریت کیفی مخزن با توجه به مشکل به وجود آمده مورد بررسی قرار گرفت و با توجه به نتایج مدل سه بعدی راهکارهای مربوطه نیز ارائه شد.
    کلیدواژگان: سازند گچساران، سد گتوند علیا، لایه بندی شوری، مدل سه بعدی، نرخ انحلال
  • شیما باچ *، احسان درستکار، سایمون بل صفحات 267-284
    پژوهش حاضر در نظر دارد تا ضمن ارائه تعاریفی برای منظرصوتی، به بررسی عوامل تاثیرگذار بر کیفیت مناظرصوتی شهری از طریق تشریح مقوله های شناختی میان تجربیات فردی، و کاربست نظریه های زبانی با به کارگیری روش های کیفی بپردازد. مبانی نظری تحقیق و عوامل موثر بر ارزیابی مناظرصوتی از نظریات محققان مختلف نظیر شافر، تراکس و... استخراج گردیده است. از روش گرانددتئوری به عنوان پایه ای برای ارزیابی شاخصهای کیفیت فضاهای شهری در بعد شنیداری استفاده شده است. به طور کلی روش تحقیق کیفی بوده و جهت ارزیابی نهایی و تحلیل داده ها از نرم افزار Nvivo استفاده می شود. شیوه جمع آوری اطلاعات میدانی و از طریق خاطره نگاری و مصاحبه با ساکنان می باشد. ارزیابی ها و نتایج تحلیل نشان می دهد که به طور عمده چهار نوع قضاوت در مورد مناظرصوتی شهر وجود دارد؛منظرصوتی بلند-پذیرفتنی، منظرصوتی بلند-ناپذیرفتنی، منظرصوتی آرام-پذیرفتنی و منظرصوتی آرام-دلهره انگیز. بیشترین قضاوت ها در مورد مناظرصوتی نامطلوب که بیانگر آلودگی صوتی بیش از حد مجاز در سطح نمونه موردی بوده است؛ بیان شده است. در نهایت از مدل سونوتوپ هدفورس برای مشخص نمودن انواع چهارگانه مناظرصوتی استفاده شده است تا بتوان با شناسایی مناظرصوتی نامطلوب یا منفی به ارائه راهکارهایی جهت ارتقاء کیفیت پرداخت.
    کلیدواژگان: صوت، منطقه 12 تهران، منظرصوتی، NVivo
  • وحید امینی پارسا، احمدرضا یاوری*، اطهره نژادی صفحات 285-301
    مناطق حفاظت شده علی رغم اقدامات حفاظتی در معرض تغییرات کاربری زمین قرار می گیرند که این تغییرات ناشی از محرکه های مختلفی به خصوص نیرومحرکه های اقتصادی- اجتماعی هستند. هدف این تحقیق بررسی ارتباط تغییرات کاربری زمین و متغیرهای اقتصادی- اجتماعی آن در ذخیره گاه زیست کره ارسباران است. در این راستا الگوی تغییرات کاربری زمین در طول 24 سال گذشته برای کل منطقه و هم چنین زون های مدیریتی با استفاده از فنون سنجش ازدوری بررسی شد. ارتباط و همبستگی تغییرات کاربری زمین (متغیر وابسته) با چهار متغیر اقتصادی-اجتماعی؛ درصد تغییر جمعیت، درصد تغییر باسوادی، درصد تغییر اشتغال و درصد تغییر بعد خانوار (متغیرهای مستقل) با استفاده از رگرسیون چند متغیره مورد تجزیه وتحلیل و مدل سازی آماری قرار گرفت. نتایج نشان دهنده تخریب 59/5464 و 07/1351 هکتاری سطوح جنگلی به ترتیب در کل منطقه و زون مرکزی بین سال های 1989 تا 2013 هست. در این بازه میزان کل تخریب در منطقه برابر 24/12012 هکتار به دست آمد. بررسی همبستگی پارامترهای مستقل با پارامتر وابسته نشان دهنده معنی دار نبودن درصد تغییر سواد بوده و از مدل حذف شد. متغیرهای باقی مانده در مدل لوجستیک و استفاده از روش اینتر به عنوان الگوریتم مدل سازی خطی وارد شدند و مدل همبستگی و پیش بینی تخریب از طریق متغیرهای اقتصادی- اجتماعی حاصل شد.
    کلیدواژگان: تخریب زمین، نیرومحرکه ها، متغیرهای اقتصادی- اجتماعی، مناطق حفاظت شده
  • امیر رضا حیدری، اکرم عوامی*، محمد آقچه لو صفحات 303-316
    جای پای بوم شناختی، شاخصی است که جهت کمی سازی اثرهای محیط زیستی زندگی انسانها مورد استفاده قرار می گیرد. در این پژوهش، شاخص جای پای بوم شناختی برای ارزیابی تاثیرات زیست محیطی فعالیت های دانشکده مهندسی انرژی دانشگاه صنعتی شریف مورد استفاده قرار گرفته است. بدین منظور داده های مورد نیاز، از قبیل مصرف انرژی و آب و تولید پسماند دانشکده به صورت مستقیم جمع آوری گردیده است. همچنین جهت محاسبه ی مصرف غیرمستقیم انرژی ناشی از حمل و نقل دانشجویان، پرسشنامه ای تهیه گردیده است و از نتایج آن برای تخمین مصرف سالانه انرژی در هریک از روش های حمل و نقل استفاده شده است. در نهایت با استفاده از روش استاندارد، شاخص جای پای بوم شناختی برای فعالیت های دانشکده محاسبه گردیده است. نتایج بدست آمده حاکی از آن است که جای پای بوم شناختی دانشکده معادل با 41456037 هکتار جهانی در سال می باشد که بخش عمده ی آن مربوط به مصرف گاز و برق در ساختمان دانشکده مهندسی انرژی دانشگاه صنعتی شریف است. لذا کاهش مصرف انرژی ساختمان تاثیر چشمگیری در کاهش این شاخص خواهد داشت. همچنین افزایش درصد بازیافت زباله و نیز افزایش استفاده از حمل و نقل عمومی از دیگر راهکارهای کاهش این شاخص می باشد. میزان تاثیر هریک از این راهکارها در کاهش جای پای بوم شناختی دانشکده به تفصیل بررسی شده است.
    کلیدواژگان: ارزیابی اثرهای محیط زیستی، جای پای بوم شناختی، دانشکده، مصرف انرژی
  • ابراهیم انواری *، سمانه باقری، احمد صلاح منش صفحات 317-327
    رشد اقتصادی یکی از اهداف اصلی کشورهاست، ممکن است رسیدن به این هدف، به آلودگی های زیست محیطی منجر شود. مقاله حاضر برای نخستین بار به آزمون فرضیه کوزنتس با روش گشتاور تعمیم یافته در قالب دو مدل برای کشورهای عضو اوپک می پردازد. در این مطالعه فرضیه منحنی زیست محیطی کوزنتس برای کشورهای عضو اوپک، با استفاده از روش گشتاور تعمیم یافته برای دوره زمانی 2013-1992 بررسی شد. CO2 به عنوان بیشترین سهم در ترکیب گازهای گلخانه ای، برای آزمون فرضیه کوزنتس مورد استفاده قرار گرفت. بر اساس نتایج به دست آمده فرضیه منحنی زیست محیطی کوزنتس برای کشورهای اوپک در قالب هر دو مدل پذیرفته نشد، مسیر آلودگی این کشورها هنوز به سرعت صعودی می باشد و به شرایط نقطه بازگشت منحنی نرسیده است. در واقع میزان انتشار گاز دی اکسیدکربن در این کشورها در فرآیند رشد اقتصادی به طور مستمر افزایش می یابد. رشد شهرنشینی، رشد جمعیت، مصرف انرژی و تولید ناخالص داخلی حقیقی بر انتشار گاز گربنیک اثر مثبت و معنی داری در کشورهای عضو اوپک دارد. در بین کشورهای عضو اوپک، عربستان بیشترین انتشار گاز کربنیک سرانه و رشد اقتصادی را داراست و ایران جایگاه چهارم را در انتشار گاز کربنیک سرانه، رشد اقتصادی در کشورهای عضو اوپک دارد.
    کلیدواژگان: ایران، آلودگی محیط زیست، کشورهای عضو اوپک، گشتاور تعمیم یافته، منحنی کوزنتس
  • مهری استادی، هادی سلطانی فرد*، حامد ادب، زهرا قلیچی پور، عباس پهلوانی صفحات 329-347
    توسعه فیزیکی شهرها در دهه های اخیر باعث ایجاد دگرگونی های عمده ای در شرایط محیطی و اکولوژیکی شهرها شده است. افزایش مهاجرت، تغییر کاربری اراضی و شیوع آلودگی ها، از عوامل اصلی در تغییر کیفیت و پایداری شرایط اکولوژیکی در محیط های شهری است. برای به حداقل رساندن این امر در محیط شهری روش های ارزیابی مختلفی پیشنهاد شده است. یکی از این روش ها، ارزیابی کیفیت شرایط اکولوژیک شهری با تکیه بر دانش سیمای سرزمین می باشد. هدف از این مطالعه ارزیابی کیفیت اکولوژیکی فضاهای سبز مناطق شهری مشهد و رتبه بندی آنها است.در این مطالعه برای تهیه نقشه فضای سبز شهر مشهد از تصاویر ماهواره ای لندست 8 سال 2014 و نقشه کاربری اراضی مشهد (1390) استفاده شده است. مدل ارزیابی کیفیت براساس شاخص های کمی و کیفی و مبتنی بر متریک های سیمای سرزمین است. متریک های مورد استفاده شده در این تحقیق شامل: NP، CA، PLAND، LPI، LSI، MESH، DIVITION، TE، ED، SHDI است و از ابزار GIS 10.3 و FRAGSTAT 4.3 در این تحقیق استفاده شد. نتایج حاصل از این تحقیق نشان داد که منطقه 5 دارای بهترین کیفیت اکولوژیکی است و در نقطه مقابل منطقه 12 مشهد نامطلوب ترین کیفیت اکولوژیکی را دارا است.
    کلیدواژگان: تاپسیس، رتبه بندی، کیفیت اکولوژیکی، فضای سبز، مناطق شهری مشهد
  • مصطفی محمدی ده چشمه *، فرشته شنبه پور صفحات 349-364
    هرچند در عصر تبدیل شدن شهرها به نمودهای نوآوری و تجهیز آنها به تکنولوژی های نوظهور، بخشی از آسایش شهروندان حاصل شده است، ولی شهر ماشینی امروز سهم قابل توجهی از آسایش شهروندان خود را سلب نموده است! آلودگی صوتی یکی از معضلات رو به افزایش زیست بومهای شهری است که با سلب آسایش صوتی از شهروندان، به عنوان عاملی زیان آور برای سلامتی روحی، روانی و جسمی شناخته شده است. هدف از پژوهش حاضر، سنجش ضریب مکانی آسایش صوتی در نواحی کلانشهر اهواز میباشد. پژوهش حاضر از نوع توصیفی- تحلیلی و رویکرد حاکم بر آن، تحلیل مکانی میباشد. در آنالیز مکانی پس از شناخت کلیه کاربری های صداساز، پهنه بندی آلودگی صوتی در سطح نواحی کلانشهر اهواز و با استفاده از برنامه جانبی تحلیل فضایی4، و ابزار Kriging و Fuzzy Overlay و در سه مرحله انجام گرفت و در نهایت نقشه آسایش صوتی تهیه شد. یافته های پژوهش حاکی از آن است که، ناحیه 4-2(ناحیه 4 در منطقه 2) با ضریب مکانی (879/0) و ناحیه 1-6 (ناحیه 1 در منطقه 6) با ضریب (807/0) از کمترین آسایش صوتی برخوردارند و همچنین نواحی 1-5 (ناحیه 1 در منطقه 5) و 5-4 (ناحیه 5 در منطقه 4) از بالاترین ضریب آسایش صوتی برخوردارند.
    کلیدواژگان: آسایش صوتی، آلودگی صوتی، ضریب مکانی، کلانشهر اهواز
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  • Sahar Sheibani * Pages 181-193
    Experimental
    Wastewater station and monitoringWater Reclamation Plant is located in Shiraz industrial town, Fars, Iran. Wastewater of 1100 small and medium industrial units are collected through the sewage system and treated in this station. Its capacity is 2500 m3 per day but now, loaded wastewater is only about 1200 to 1500 m3 per day. Treatment Methods is completely biological and chemical purification method does not use in reactors. Logon and stilling pond with anaerobic system, UABR system, UASB, Selector, SBR and wetland are the parts of this plant. Biological treatment starts from anaerobic lagoons, that wastewater fixation done there, afterward gas and methane produced as a result of bacteria’s activity. At this point, pollution concentration decreased and the amount of COD reduced. In order to wastewater could achieve suitable retention time to provide sufficient time for the biological response, two lagoons and a stilling pond designed between the lagoons that is Plug Flow reactor type. This system will reduce energy consumption and operating costs. Depth of lagoons is about 5 to 6 meters and stilling pool depth is 120 cm in stilling pond sewage find enough time to complete the biological process. Wastewater inters to lagoon1initially and after crossing the stilling pool sheds to the lagon2. In stilling pool sewage find enough time to complete the biological process. Sludge deposited along the way and not transferred to the next unit, sludge are drains from lagoons once a week.
    DataChanges in effluent before and after crossing the zeolite channel were measured according intended indices in the laboratory by regular sampling (90 samples during 3 month). PH, temperature, TSS, TDS, EC, and COD of wastewater that loaded and exceeded to zeolite channels were measured. Same analysis methods were applied to determine the effluent characteristics.
    Modeling processIn order to model the effect of zeolite channels on the wastewater characteristics at first the relationship between daily values of (EC) and COD of exceeding effluent from Shiraz industrial town treatment plant after crossing the zeolite channel according other examined factors of loaded wastewater was studied. For this purpose, values of indicators such as PH, temperature, TSS, TDS, of loading wastewater was used as known values and factors such as EC, and COD were considered as unknown values. Correlation coefficient was used to predict wastewater quality parameters. Then curve fitting approach was used to consider several linear and non- linear models to simulate this correlation. This method was used to find the correlation coefficients between exceeding COD and EC and other loaded factors from industrial wastewater. The results of forecasting models in the calibration phase and the results of their validation process were used to select the appropriate model.
    Performance of models, were studied according to Root Mean Square Error (RMSE). Then, curve fitting approach used to achieve a simulation model on relationship between the normalized data of exceeded daily COD and loaded TDS on previous day. Several linear and non linear models based on curve fitting approach used to find a simulation model for defining the relationship between the normalized data of exceeded daily COD and loaded TDS at previous day. Then cluster analysis and the fuzzy inference system applied to improve the simulation of this relationship. The best correlation coefficient and p-vale were obtained between the exceeded values of EC and the loaded values of TSS for each day. Equations could be shown as follow:CODE (t)= F(TDSL(t))(2)
    ECE(t)= F(TSSL(t)) (3)
    The correlation coefficients of COD with TDS, and COD with TSS were 83% and 90%, respectively. Because measuring TDS is easier than the TSS then equation 2 was selected to estimate COD.
    ARIMA models results offered the log time of one day have the best relationship than other models. Daily changes in TSS and TDS according to their value of the one day before predicted. This model predicted EC(E) and COD(t) through TSS(L) and TDS(t-1). As a result, the decision maker could be having the optimization analysis by means of practical strategies to change the collection network or Zeolite filtration capacity.
    CODE(t)= F(TDS L(t-1))(4) ECE(t)= F (TSS L(t-1)) (5)
    After that curve fitting approach with and without normalized data were used, to achieve a function of CODE(t) based on TDSL(t-1) and ECE(t) with TSSL(t-1). These approaches couldn’t improve the regression coefficient of each linear and nonlinear function too. Weak relationships between CODE(t) and TDSL(t-1) is the cause of how data distribution which are illustrated in figure3. As shown in table 4 it was assumed that this trend has the fuzzy behavior and using the fuzzy inference systems (FIS) model was appropriate to simulate this distribution. Therefore, at first the membership functions of input (TDS (t-1)) and output (COD (t)) variables in Mamdini approach was defined based on the average of each class.
    Result and discussionWith the study purposes of achieving the appropriate model of variability of TDS(L), TSS(L), and exceeded COD(E), EC(E), no significant correlation coefficient were obtained by analyzing approaches such as multivariate, curve fitting with linear and nonlinear models, time series, and clustering with and without normalized data. Therefore, the results of classification were utilized to define the mean and range of each membership function for input variables TDS(t-1) and the output COD(t).
    As noticed, fuzzy roles describe data distributions of input and output variables which other deterministic models couldn’t consider subject matter. Feature of fuzzy roles in this point caused a good conformity with estimated and measured values of exceeded COD(t) with R2 = 0.76. As a result, fuzzy behavior assumption of data distribution was admitted. The result of simulation model showed that data distribution of input variables TDS(t-1) and the output COD(t) function was similar to S shape curve. It could be refer to Zeolite channels filtering capacity.
    FIS simulation model had good corresponding with distribution of measured and observed data of COD (t) R2 = 0.76. As seen in figurer 3 and 4, Zeolite filtering capacity may be affected by other factors. Low input of TDS observed when rainfall occurred, so entering wastewater content and loaded TDS affected by runoff.
    The result of simulation model showed that a certain range of TDS exists in which Zeolite could be effective. In this study, TDS threshold occurred in 1746ppm in which COD is equal to 52. Result obtained in this study indicated that, fixed value of soluble solids concentration on mass transfer of wastewater entering the treatment plant had important role in the effectiveness of Zeolite filtration.
    As seen in figurer 4c and 5, while loaded TDS was low and high, then exceeded COD was high and low or closed to standard level, respectively. This result indicated that Zeolite filtering capacity maybe affected by other factors. Low input of TDS observed when rainfall occurred, so entering wastewater content and loaded TDS affected by runoff. In the other word, while the volume of wastewater increased during this period, TDS values decreased.
    In this condition, loaded wastewater was more than daily filtering capacity of Zeolite Channel. Although TDS values were low, the volume of wastewater entering to the treatment plant was high then Zeolite channel could not operate its ion exchange capacity appropriately. Its filtering operation was better when a few wastewaters with more TDS value entered to the Zeolite channel. Finally, this result could be achieved that to manage wastewater treatment loaded amount of pollutants and mass transfer of wastewater trough Zeolite channel should be controlled together.
    The best regression coefficient of EC(E) with the TSS(L) was less than 0.5. Curve fitting approaches could not improve the regression coefficient of each linear and nonlinear function too. Based on the results of clustering analysis the ranges of ECE(t) and TSSL(t-1) variables classified into three major classes. FIS simulation model had not good corresponding with distribution of measured and observed data of ECE (t).
    Keywords: Optimization, zeolite, Fuzzy simulation, Industrial wastewater
  • Hoseiin Ganjidoost * Pages 195-206
    IntroductionThe aim of this study was to evaluate the efficiency of electrochemical systems for removing of Acid red 14 contaminants, in which electrical coagulation and flotation methods by steel electrodes, are used simultaneously. It is expected that, simultaneously using of electrical flotation and electrical coagulation process eliminate gravity sedimentation unit for the separation of the clot, and result both in the separation of emissions and reducing the cost of the treatment. Researches in the field of electrochemically dye removing methods, are based on electrical coagulation, and flotation property of bubbles are rarely used. In this research, innovations such as gridded horizontal were used to improve the performance of flotation. The impact of key parameters on electrochemical system performance including current density and initial dye concentration was examined and optimized based on the amount of energy consumption and anodes consumption and ensuring the proper functioning in terms of coagulants and bubbles. In optimum conditions, in order to evaluate the performance of coagulation and flotation process in treating of real wastewater plants, electrochemically treatment of the actual colored wastewater was evaluated.
    Materials and methodsCubic Plexiglas electrochemical cells with small dimensions of 15×7×7, with a pureed volume of 735 ml was used for electrical coagulation and electrical floatation process. Two mesh stainless steel 316 electrodes with a purity of 99%, with horizontal monopole arrangement was used as the anode and cathode in the reactor. Because hydrogen gas at the cathode, play a key role in floating suspended particulates, current flow was introduced in a way that, the cathode and anode was placed on top and down, respectively.
    Acid red 14 dyestuff, which was used as the main contaminants to create artificial wastewater, is anionic and has an Azo group with chemical formula of C20H12N2Na2O7S2 and molecular weight of 502.4 gr/mol. In addition, in order to evaluate the effectiveness of the system in optimal conditions, discoloration of real wastewater were studied.
    In order to determine the optimal electrical current density and optimal initial concentration of dye by using of single-element method, synthetic wastewater was prepared with desired specifications.
    Results and discussionIn order to determine the optimal amount of electrical current density, experiments are performed in different electric current densities when other affecting parameters considered to be constant. According to the observations, by increasing the amount of electric current, the speed of dye removal is increased. This is because, production speed of coagulants and hydrogen and oxygen gases has been increased by increasing current density, which leads to coagulation, flocculation and faster separation of contaminants. The specific energy consumption and reduction of the anode metal mass are evaluated as a criteria for better comparison of the economic and environmental terms according to which, by removal efficiency of 99% in 10, 20, 30 ,40 and 50 mA/cm2 electrical current densities and for kg dye removal, energy consumption is respectively 3.57, 3.22, 3.19, 2.52 and 2.26 kWh and anode consumption rate is 0.4, 0.34, 0.63,0.54 and 0.67 kg Fe/kg Dye Removed, respectively. Finally, the optimal electrical current density was selected equal to 20 mA / cm2 (0.4A) according to the results, in which 99% of dye was removed in less than 20 minutes, and the amount of specific energy consumption was 3.22kWh / kg Dye Removed, anode’s consumption was 0.34kg Fe/kg Dye Removed and the TSS of sludge was 3820mg/L.
    Various experiments with different concentrations of dye take place in order to determine the optimal value of this parameter with optimized electrical current density where other parameters were kept constant. According to these tests, dye removal rate decreased with increasing initial concentration and more time is required in order to get fixed removal efficiency. This is because at a constant electric current density, the produced coagulant metal hydroxide is constant with time and this amount of metal hydroxide is not sufficient to coagulation and flocculation greater amount of pollutants. It should be noted that at very high concentrations (500mg/L) dye removal process go slower but the performance is much better in compare with other studies. By comparing of energy and anode’s consumption with efficiency of dye removing in terms of time, the optimum concentration was selected equal to 250 mg/L, in which 99% of dye was removed in less than 30 minutes, and the amount of specific energy consumption, anode’s consumption and TSS of sludge were 1.9kWh/kg Dye Removed, was 0.95kg Fe/kg Dye Removed and 3700mg/L, respectively .
    Using the optimal conditions obtained from previous experiments, to evaluate the performance of coagulation and electrical flotation process in real waste water treatment, real sewage electrochemical treatment for actual dyeing is considered, in which, after 30 minutes treatment by removal efficiency of 63%, the primary COD equal to 803 mg/L reached to 296 mg/L. In synthesized sample, after 30 minutes treatment with removal efficiency of 79%, the primary COD magnitude decreased from 278 to 58mg/L. This amount is lower than the standard limit of discharge to surface water and catchy wells. After 30 minutes treatment with removal efficiency of 77%, the color of actual wastewater decreased from 1.5 Gardner in the beginning to 2.1Gardner. The energy and anode’s consumption in actual wastewater treatment for removing of 63% of COD in 30 minutes, were 3.11 kWh/kg COD Removed and 0.565 kg Fe/kg COD Removed respectively. These values for synthetic wastewater with removal efficiency of 79% in the same time were 2.10kWh/kg COD Removed and 1.38kg Fe/kg COD Removed, respectively.
    ConclusionElectrical coagulation and flotation has the advantages of low sludge production, in comparison with similar methods and fully automatic and continuous operation is possible. The parameters involved in the process can be controlled easily and the safety of equipment is high. Tiny bubbles with the same size are produced and there is a little or no need to add chemicals. Also, very high tolerance against organic, hydraulic and toxins shocks and reduced number of processing plants and thus reducing the required surface for treatment plant and reducing in operating costs are another advantages of this method.
    By increasing of electrical current density, production speed of coagulants and gases were increased, which lead in faster coagulation, flocculation and flotation. However, when electrical current density is increased in very high rate, the amount of iron in the separated sludge is increased with high speed. Increasing of iron clots in the water containing sludge, in spite of their high volume, and because of lightness, reduce the TSS of separated sludge and therefore the ability of system in flotation and separation of clots is reduces.
    Due to the limited amount of coagulants produced at a time of electrolysis and consistency of electrical current density, with increasing of initial concentration of dye (from 50 to 500mg/L), the removal efficiency was decreased. However, according to the amount of energy used and the high dissolution of anode at lower concentrations, concentration of 250 mg / L was chosen as the optimal concentration.
    Anode consumption and the need for its renewing and cathode corrosion are the disadvantages of this method. However, according to results, 99% of dye was removed in less than 30minutes, where specific energy consumption was 1.9kWh/kg Dye Removed, the anode’s consumption and the TSS of sludge were 0.95kg Fe/kg Dye Removed and 3700mg/L, respectively. These results proved the ability of electrical flotation and coagulation methods in treatment of wastewater containing dye, with low consumption of materials and energy. The proper functioning of this procedure in real waste water treatment, which are containing different combinations of colored dyes, suggest that, this method can be used for wastewater treatment in dyeing industry, textile and other industries. In addition, low sludge produced in this treatment reduces sludge’s treatment, disposal, and its relative problems costs. As a result, using of this method as an alternative option to conventional methods is considerable.
    Keywords: Anode dissolution, Dye removal, Current density, Concentration, Real wastewater
  • Majid Afyuni, Somaye Sadr * Pages 207-218
    IntroductionHeavy metals in the soil are an important indicator of global environmental contamination and constitute an important part of the pollutants, which due to toxic and aggregate properties, even at low concentrations, have high environmental significance. Therefore, the distribution of their contamination is highly noticeable. Population growth, urban expansion, industrial development and distribution without management in agricultural inputs are among the most important factors in increasing the concentration of heavy metals. To improve the management recommendations for controlling and eliminating these pollutants, it is necessary to determine the spatial pattern of pollutants. In practice, the precise separation of ground contaminated with heavy elements is difficult due to the complexity of the pattern of spatial variations, the severe changes, and the presence of local contaminants. But there are several studies for the interpolation and determination of spatial distribution of heavy metals concentration in the soil. The analysis of the spatial distribution of heavy metals in soils is of fundamental importance in a vast number of applications, including general soil surveying and characterization, delineation of potentially polluted spots at unsampled sites, or planning remediation strategies. The relevance of heavy metal soil pollution has favoured the application of advanced geostatistical techniques such as kriging in their different varieties. Kriging techniques have also been widely applied in other earth sciences applications such as mapping of precipitation, air temperature or solar radiation at different temporal and spatial scales. Vanadium is a trace element, which is widely distributed in nature. The average abundance of vanadium in the crust is approximately 0.01% Vanadium in the environment comes from :( 1) weathering of parental rocks; (2) combustion of fossil fuels; (3) mining and high-temperature industrial activities including steel-iron refining, electronics and dyeing, etc. While in the soil, vanadium is derived from parental rocks and deposits Human activities, such as the disposal of vanadium-contained waste and oil leakage, may also provide a certain amount of vanadium to the soil. Consequently, there are few countries, where standards and regulations for environmental pollution in soil with vanadium are accepted, for example, Russia, where the maximum of 150 g g−1 allowed in agricultural soil Because of industrial activities and anthropogenic emissions, the concentrations of vanadium in soil have increased significantly in recent years, and the number of people affected by vanadium pollution is also increased. The purpose of this paper were to: (i) estimate the upper baseline concentration of As in topsoils of Isfahan Province (central Iran); (ii) evaluate factors controlling the spatial distribution of soil V concentrations and (iii) delineate polluted from unpolluted areas using geostatistic methods.
    Materials & MethodsThis research was conducted in Isfahan province, central Iran. Isfahan has an arid climate and is about 6800 km2 around Zayandehroud River. Mean annual precipitation and temperature are 120 mm and 14.5 oC, respectively and direction of dominant wind in study area is NW-SE (Fig 2b). the area extends from easting of 51o15' to 52o41' longitude and northing of 32o7' to 32o59' latitude. The area covers different land uses including agricultural, industrial, urban and uncultivated lands. There are several big steel factories in the study area. The underlying geology consists mainly of recent terraces, resent alluvial deposit and undifferentiated terraces, all of quaternary age. In addition, lower Cretaceous grey limestone containing Orbitalin and Jurassic shale are found in the south west and south of region.
    In this study, soil sampling strategy was random stratify. A total of 207 soil samples (0-20 cm) were collected. At each sampling point the coordinates were obtained using a portable GPS and its land use was recorded the distances.
    Soil samples were air dried and ground to pass through a 2 mm sieve. Total V concentration in the soil was determined by XRF.
    Statistics including mean, variance, maximum, minimum, coefficient of variation (CV) were calculated using SPSS 11.0 for Windows. Based on the land use information, data sets were grouped into three subsets: industrial and urban, agricultural and uncultivated lands. After calculation, 46.5% of the sampling locations occurred in agricultural lands, 43.5% in uncultivated lands and 10% in industrial and urban areas. The ANOVA was then used to compare the effect of land use.
    The spatial variability analysis is a necessary step prior to applying kriging techniques In this work several theoretical variogram functions including linear, exponential and spherical forms considering nugget effects were evaluated using the VARIOWIN and WINGSLIB software. With the sets of fitted variogram functions, the next step is cross validation of the prediction models with MSE. Distribution maps of V was produced using the ordinary kriging procedure and mapped. Correlation coefficient (Pearson) computed between real and estimated data with ordinary kriging that this parameter is identifier of relatively high accuracy estimation in maps. Maps were produce with Surfer (version 10) and ILWIS (version 3.3).
    Discussion & ResultsThe average V concentration was 82.9 mg/kg with range of 19.2-140.1 mg/kg in Isfahan surface soils. Total V concentration was scanned for trend determination and no trend was apparent. Therefore, V concentration roughly followed a normal distribution indicating that the data is from a single statistical population. Total V concentrations in different land uses were compared using one-way ANOVA. Total V concentrations were significantly affected by land use and Total V concentrations in agricultural lands also industrial and urban areas are higher significantly. Directional variograms for V concentration computed along twelve directions of azimuth 30 degree with tolerance ± 15 degree. The best variograms fitted in directions of 90 degree and a spherical theoretical covariance model suitable for spatial fields was fitted. Present of spatial dependence (sill/ C0) indicate that distribution of V have Intermediate spatial dependence class. Distribution maps of V indicate high concentration of V in parts of east Isfahan province and industrial and mining activity are important factor to concentration of vanadium in this regions and direction of dominant wind which has affected spread of V in east of the study area. Pearson coefficient in V concentration was rather high and this parameter is identifier of relatively high accuracy estimation in maps.
    ConclusionThe overall distribution of heavy metals in surface soil can be due to local changes in rock, land use, and climatic processes. The average V concentration is 82.9 mg/kg in Isfahan surface soils and this is not higher than global average concentration. Land use did have significant effect on V concentration. Agricultural and industrial activities are probably effective factors causing increase the V concentration in the region. Vanadium is one of the impurities of earth crust deposits. Considering the wide expansion of industries such as Isfahan Iron Ore in the Lenjan and Mobarakeh Steel Area in Mobarakeh, and also the significant difference in the average concentration of vanadium in urban land-industrial areas with incult land, the role of industrial activities in these areas can be increased in extend of vanadium. Direction of dominant wind have affected in spread of Vanadium in the high concentration spot in study area.
    Keywords: Isfahan, Geostatistic, Kriging, Vanadium
  • Mohsen Rezaei *, Rashid Zivari, Javad Ashjari, Abdolreza Kaboli Pages 219-231
    IntroductionCarbonate formations (including karst springs and wells), have important role in supplying domestic and irrigation water in our country. Along with the exploitation of these resources, it is required to be considered geochemical characteristics and factors affecting water quality changes. Khosh-Yailagh carbonate formation is a formation of Devonian age in the north of Iran. The outcrops are located in mountainous areas and in the margins of Gorganroud plain. The local base level of erosion is high due to particular tectonic behavior. Because of low thickness and coarse texture of alluvium, well yields are not respond to different uses.
    Groundwater hydrochemical assessment is usually based on a set of comprehensive information about the chemistry of groundwater. Chemistry of groundwater is affected by different factors such as geology, climate, type of rock weathering reactions, and recharge water quality (Guler et al, 2004; Subramani et al, 2005; Coetsiers, 2006).
    The purpose of this study is to evaluate the evolution of geochemical processes and water quality of Khosh-Yailagh carbonate formation. Water quality graphic methods, multivariate statistical methods, hierarchical cluster analysis (HCA), principal components factor analysis (PCA) and chemical mass balance were used in determination of hydrochemical parameters and assessing geochemical process of water of carbonate formation.
    Materials and MethodsThe study area located in the east Alborz structural-sedimentary zone in Golestan province, north of Iran between the N36º48' 00" to S37º00'00" and W54º47'00" to W55º08'00". Minimum height in the region of 118 meters and a maximum altitude is 1834 meters. Various formations outcrop in the study area. Khosh-Yailagh is the most important of these formations, which is carbonate with karst development potential.
    20 water samples were collected from springs. Field analysis of Temperature, pH and conductivity was done when the sample is collected. The major elements (Na, Ca2,Mg2, K, Cl-, SO42-, HCO3-, NO3-) were analyzed in the lab using standard methods. Composite diagrams were used to indicate relation between different ions. The statistical technique of multivariate analysis was used to characterize hydrochemical processes through data reduction and classification. The factor analysis derived principal components from a correlation matrix and rotated axes with a quartimin rotation.
    Discussion of ResultAll of the groundwater samples are low salinity with electrical conductance ranges from 220 to 706μs. All groundwater samples have carbonate-Calcium type. Clustering analysis was used for combining cases (water samples) into clusters. This clustering routine resulted in three groups of water samples on the basis of variables (pH, EC and major elements).
    Group 1: low salinity waters (309 ≤ EC ≤ 589μs) (samples 1, 2, 5, 10, 11, 12, 13, 14, 18, and 20). Average TDS of this group is 41.27 mg/l.
    Group 2: low salinity waters (451 ≤ EC ≤ 538μs) (samples 4, 7, 8, 15 and 16). Average TDS of this group is 37.22 mg/l.
    Group 3: electrical conductance of this group ranges between 495 to 706μs. This group contains samples 3, 6, and 19. These samples indicate more water-rock interaction. Groups 1 and 2 are more similar and could be consider as one group.
    Most measured parameters showed weak correlation, which is the evidence on the effects of different processes in the water chemistry. Factor analysis was applied to identify the dominant processes controlling major chemical components of groundwater. The variables for factor analysis were Na, K, Mg2, Ca2, HCO3-, Cl-, SO42-, EC and pH. The virmax orthogonal rotation method was applied. Four factors are extracted to represent the contributions influencing chemical composition of groundwater (Table 1). The variables of TDS and Ca, have high positive loading of factor 1. The variables K and HCO3 have high positive loading of factor 2. The factor loading of pH show high positive value on factor 3. The variables Na and Cl have positive loadings on factors 4.
    Table 1. Results of principle component analysis
    VARIABLES Component
    P1 P2 P3 P4
    TDS .916 .507 -.770 -.040
    pH -.082 .007 .969 .017
    Ca .895 .263 -.004 .009
    Mg -.907 .316 .211 .056
    Na -.306 .195 -.325 .785
    K .190 .844 -.199 .131
    HCO3 -.211 .774 -.015 .287
    Cl .193 .201 .335 .796
    % of variance 24.072 23.207 20.463 17.252
    Ion-exchange reactions occurs, both positive and negative direction that depends on the flow distribution and mixing of groundwater. In order to understand the dominant lithology of environment in which water is flowing, the molar ratio of calcium and magnesium was used. Molar ratio of 1.44 represents interaction of water with dolomitic limestone and dolomite formations. Saturation indices of calcite, dolomite and gypsum indicate that the groundwater is not at the chemical evolution.
    The processes that govern changes in the groundwater composition, as interpreted from the factor analysis are mainly determined. In plotted Gibbs diagram, the water samples lie in field of water rock interaction. Dissolution and precipitation of carbonate minerals is the main factor controlling chemistry of groundwater in the study area. Cation exchange processes influence the concentration of cation such as Ca, Mg and Na. Rainwater that is charged with biogenic and atmospheric CO2 is another component determines chemistry of groundwater in the recharge area.
    Keywords: Saturation index, Multivariate Analysis, Carbonate Spring, Khosh-Yailagh, Hydrogeochemistry
  • Saeed Mardan*, Saeed Gitipour, Mohammadali Abdoli Pages 233-250
    IntroductionThe soils which are contaminated with oil hydrocarbons and heavy metals are among the environmental issues. Therefore, remediations of these soils are necessary according health and environment standards and needs to be under consideration by decision makers. Solidification and stabilization of oil hydrocarbons and heavy metals is well known as an appropriate technology in prohibition of contamination movement to the base layers of soil and underground water resources. The contamination of underground water resources often happens because of subsurface leakage of pollutants from soil to the subsurface layers. Organic hydrocarbon especially those originated from oil are the most prevalent soil contaminants. Hydrocarbon contaminants are among the family of carcinogens and neurotoxic organic pollutants. Therefore, remediation of contaminated soils with organic contaminants are necessary. The process of solidification and stabilization changes of the oil hydrocarbons and heavy metals into more stable materials from which the leakage of contamination is minimum. This process takes place by methods such as encapsulation or adsorption of the contaminant. Organophillic clay shows a great capacity in oil hydrocarbon or heavy metal contamination stabilization because of high specific area and cation exchange capacity. The main goal of this paper is to study the process of interaction between cement-lime-organophillic clay and oil hydrocarbon or heavy metal contamination considering microstructure in solidification and stabilization process. The leakage of contaminant from the solidified matrix is also studied and the best mixing fraction of stabilizer and solidifier for the best result is calculated.
    Materials and MethodsThe main focus of this research is on solidification and stabilization process in removal of the contaminants from the used bleaching soils of engine oil secondary treatments unit which are contaminated with oil hydrocarbons. This process is done using cement and quicklime accompanied by organophillic clay.
    Stabilization/solidification is an effective disposal method for hazardous contaminants such as heavy metals and toxic materials. It was firstly used for nuclear waste treatment in 1950s and got widespread as a treatment technology for hazardous wastes in 1970s. US EPA has identified S/S as the Best Demonstrated Available Technology for 57 hazardous wastes which are regulated. Figure 7 shows the frequency of S/S treatment method compared to other technologies in US.
    Figure 7. frequency of S/S treatment method compared to other technologies in US
    Using S/S treatment method, chemical fixation and encapsulation of contaminants will be possible and the rate of contaminant migration will be minimized. During S/S process, the surface area exposed to leaching is decreased by isolating the wastes in an impenetrable capsule. The combination of stabilization and solidification results in improvement of strength and reduction in leachability which is the main goal of the process and hydraulic conductivity of treated soil. The aim of stabilization process is to decrease the solubility of contaminants by changing the chemical state of wastes or capsulation while solidification attempts to convert the waste into an easily handled solid with reduced hazards from leaching and higher strength. S/S can be applied both in situ and ex situ. In situ process contains the injection of agents into the contaminated soil using mixing equipment or pressure injection while in ex situ process the soil will be excavated. In ex situ systems, the control of process conditions is improved in comparison to in situ systems but its need to soil excavation is the most important drawback in comparison to in situ process. The most important parameter in S/S applicability is its limitation to immobilization of inorganic contaminants. However, under certain circumstances it can be applied to organic contaminants. The choice of appropriate binder in S/S process highly depends on the nature of contaminant and environmental conditions. The binders include inorganic cementitous materials (such as Portland cement, pozzolans, hydraulic slags and lime), organic binders, and thermosetting organic polymers.
    In the first step, the characteristics of the wastes of the engine oil treatment industry are determined. For this purpose, the sampling takes place from the waste disposal site in Salafchegan Industrial City based on the method proposed by EPA. The wastes are measured to determine the total amount of oil hydrocarbons, total aromatic hydrocarbons, heavy metals, pH and humidity. The tests for determination of density, particle size distribution, Atterberg limits, diffusivity and oil contaminant content is done as well. Studying the amount and the types of the organic compounds in the soil is a necessity which determines the remediation methods in next processes. In other words, if the soil has a noticeable amount of organic and contaminating compounds (such as polycyclic aromatic hydrocarbons), it must be clarified before being used in solidification and stabilization process.
    In the second step, the characteristics of the leakage of contaminants from the solidified samples is studied under different circumstances which is done using TCLP and free pushing resistance tests and analyzing the morphologies of the samples using SEM electroscopy.
    Portland cement, the contaminated bleaching soil, organophillic clay and quicklime are the main materials used in this research. Some solvent and chemicals are used as well which are introduced in the paper.
    Results and DiscussionThe results show that the humidity content and specific gravity of the soil are 12.26% and 1.22 respectively. The results of the tests for measuring Atterberg limits and plasticity index shows that the soil which is being studied in this research, is from the types of the soils with high concentration of organic compounds with low diffusivity. Its pH is about neutral and it is heavy soil overall. The tests of heavy metal have shown the traces of iron, barium, lead, chrome, cobalt, cadmium, manganese, copper, nickel and zinc in the soil samples but their amounts are under the standard limits except barium which is above the standard limit.
    The tests of aromatic hydrocarbons shows the existence of acenaphthylene, acenaphthene, fluorine, fluoranthene and pyrene in the soil in amounts more than other aromatic compounds but still their amounts are under the standard limits. Therefore, the soil being studied in this research does not have the polycyclic aromatic contamination potential.
    To analyze the effectiveness of the solidification and stabilization of the soil, the leakage in a control sample (without organophillic clay and quicklime as solidifiers) is measured and compared to the samples containing solidifiers. The comparison between the leaked contaminants concentrations from stabilized samples and control sample shows that in all of the solidified and stabilized samples, an appropriate percentage of oil hydrocarbon removal has happened. In other words, most of the organic compounds and heavy metals diagnosed in the soil are encapsulated in the matrix and are not present during TCLP test. It shows that using organophillic clay has a good effectiveness for solidification and stabilization of the used bleaching soil in waste disposal site of Salafchegan Industrial City. The tests of free pushing resistance show that the addition of clay will increase the resistance of the samples.
    ConclusionsThe results show that addition of the clay has reduced the leakage in the soil. In total hydrocarbon removal, the samples with 20% of cement or quicklime and 30% of organophillic clay has the highest effectiveness with 98% removal of TPH and 98% removal of barium and producing 368-398 kPa pushing resistance.
    Moreover, SEM electroscopy and TCLP test results show that increase in organophillic clay content and decrease in porosity volume in matrix are the two main reasons which enhanced the effectiveness of the stabilization process. The first will enhance the capability of the adsorption of the contaminant and the second will reduce the leakage amount.
    Keywords: leakage test, organophillic clay, polycyclic aromatic hydrocarbons, solidification, stabilization, oil-contaminated soils
  • Mehdi Mazaheri * Pages 251-265
    Investigation and Simulation of Upper-Gotvand Dam Challenge and Management Solutions
    IntroductionUpper Gotvand dam is one of the Iran’s largest dams, has been constructed on Karun River, southwest of the country. This dam has been located in the distance of 380 kilometers from the outfall of Karun River and 12 km northeast of Gotvand city, in Khuzestan Province. The important and well-known challenge about Gotvand, is the existence of massive salt formations (known as Gachsaran formation) in the dam reservoir that have been raised from the beginning of its impoundment. Predicted that with the submergence of these formations, the reservoir water be salted and caused extremely undesirable environmental consequences at the downstream.
    In order to attainment of proper operational options, the reservoir salinity stratification studies should be done. By implementation of reservoir water quality management, water can be extracted from different layers and also, the saline layers directed outside the reservoir as a water flow with lower concentrations and the risks of using saline water at downstream, can be prevented. On the other hand reservoir water quality management and assessment of its feasibility, need a comprehensive knowledge of the flow hydrodynamic coupled with salinity stratification and salt accumulation process in the reservoir. Hence, the main objectives of this study, are three-dimensional simulation of hydrodynamics and salinity/temperature stratification of Gotvand dam reservoir and presentation of the management solutions to attain this goal.
    This study investigates the feasibility of reservoir quality management, regarding to the present challenge, by three-dimensional simulation of hydrodynamics and salinity of Gotvand dam reservoir and predicts the future situation, also provides management strategies. The main innovations of the presented study, include the three-dimensional simulation of hydrodynamics and salinity of Gotvand dam reservoir, calibration of dissolution rate of salt formations by using of the remarkable measured data at dam reservoir and presentation of management strategies.
    MethodologyHydrodynamic and salinity/thermal stratification in dam reservoir, is a three-dimensional phenomenon, hence for exact calculation of variables at the surface and depth, a three-dimensional model is required. Also, the position of salt formations in the dam reservoir (which have spread on one side of the reservoir) and the need for stratification calculations in depth, necessitate application of a three-dimensional model. In this study, for simulation the mentioned phenomenon, a commercial model which has been developed by the Danish Hydraulic Institute (DHI) was used. MIKE 3 introduced since 1998 and due to its great capabilities in simulation of flow hydrodynamics and water quality, have been used in several studies. Three-dimensional simulation of hydrodynamics and salinity/thermal stratification of the Gotvand dam reservoir needs various data and parameters. It worth to mention that, for provision, verification and preparation of required data, too much time and cost were spent, which is one of the strengths of this study.
    In order to generate the horizontal mesh of the solution domain, two types of grids have been used: flexible rectangular and triangular grids. The main path of the river covered by high-density rectangular grids and the reservoir surface by triangular ones. In order to create the vertical mesh of solution domain 46 depth layers were selected, a combination of 40 Z-Level layers and six Sigma layers with equal thickness.
    Salinity sources were placed at the exact location of salt formations in the reality, in order to consider dissolution of these formations in the model. The point sources covered the entire surface of salt formations with consideration of the wall slope with a distance of 50 meters and 5 meters height difference.
    The most important part of this study is calibration of the dissolution rate of salt formations. The dissolution of salt formations in the dam reservoir is a complicated and nonlinear phenomenon, due to the effect of numerous factors, such as different water levels in the reservoir, reservoir hydrodynamics, salinity gradient and temperature, etc.
    ConclusionSeveral strategies have been presented to solve the present challenge, including removal of salt formations, preventing the contact of reservoir water with salt formations to reduce the dissolution rate, via some coatings such as geomembran or clay blanket, construction of conveyance pipelines at the reservoir bed, in order to transfer salt to the Persian Gulf and finally the reservoir water quality management.
    In this study, the reservoir water quality management, through water extraction from various layers, has been investigated. Due to complex circumstance of the problem, it is difficult to predict the future condition of the dam. Here, a 3D numerical simulation was implemented for accurate prediction of the reservoir water quality conditions with respect to time, in the interaction with salt formations, and salinity /thermal stratification into the dam reservoir obtained. Using the model results, the reservoir can be monitored in terms of salt accumulation, so the quality management strategies can be offered.
    Based on the results of dissolution rate calibration, it was found out that the amount of dissolution was not constant during the impoundment and varies according to water extraction method (decreasing and increasing at the rate of inflow and outflow and the outcrop surface of the salt formations). In this study the minimum and maximum value of dissolution rate obtained as 0.5 and 7 centimeters per hour, respectively.
    The most effective factor in the variations of dissolution rate is variations in flow hydrodynamics in the dam reservoir, due to its three directional variations in different stages of impoundment, results in various dissolution rates. Also, the results of thermal stratification of the Upper Gotvand dam reservoir indicate that due to extreme variation in temperature in the dam reservoir site and because of highly variable salinity at different depths of the reservoir, there are different patterns of stratification cycle and overturning.
    Another important point is that at the time of simulation, with the assumption of equilibrium dissolution rate as 0.5 centimeters per hour and consideration of imported salinity of upstream boundary and salty rivers leading to the reservoir, the salt accumulation amount in the reservoir will be 875 kg/s, which failure in discharge of that, results in a severe salinity gradient and serious challenges for the Upper-Gotvand dam. Discharge of accumulated salt by downstream outflow can prevent from salt accumulation in the reservoir, so the amount of flow discharges and corresponding salinity concentrations have been proposed. However, this act will follow the degradation of downstream water quality and relevant consequences; including the loss of agricultural land efficiency, degradation of water quality at downstream and environmental impacts. As a solution, the discharge of salinity could be conducted in the non-cultivation seasons and according to the associated standards, that need further investigations at downstream.
    Keywords: Gachsaran salt formation, Gotvand Olya dam, Three-dimensional model, Dissolution rate
  • Shima Bach *, Ehsan Dorostkar Pages 267-284
    IntroductionAccording to the definition of Trucks the soundscape concept is a subjective component. It means the way that the environment is understood by the individuals and communities and it examines concepts such as people's expectations. The last attempt to define the soundscape has been carried out as an interdisciplinary subject that is related to an ISO group called ISO / TC 43 / SC 1 / WG 54, that is obliged to provide a comprehensive and standardized definition of the landscape term after examining the 24 participating countries: "A acoustic environment which is perceived experienced or understood by a person or group of people.” Definitely, all of these definitions focus on the two main issue "environment" or "listener person". There is a lot of study that define the soundscape based on the acoustic environment and the place of the individual. But, in newer definition the main emphasis is on the listener person.
    Materials and MethodsSince the assessment of the soundscape is an interdisciplinary subject and is examined from different aspects (Social sciences, environmental, psychology, design, planning and urban management, landscape architecture, acoustics, etc.), So, it seems that using a combinatorial approach is more logical that can cover the existing approach as much as possible. Therefore, in this study, the various methods and models have been used to progress for each target of the study. First, the use of the grounded method was selected for the fieldwork and data analysis. Since, the main emphasis of this method is on the results arising from the memory writing of the participants, in other words, it is based on the listener’s individual in the research process, because in the recent years, most of studies have emphasized to the individual than the place or acoustic environment, that this indicates a shift direction in the definition and evaluation of the soundscape. For this purpose, it is required to express all the subjects related to how a listener’s individual can be the center of this study and "using a linguistic approach to apply its concepts for the recognition of soundscape issues". Finally, the model of "soundscape planning of the Pier Headforce has been used that is known as the Sonotop map to provide better solutions. This model has been also used somewhat in the Global Sustainable Soundscape Network project (CNH-RCN).
    Discussion of the ResultsThe final evaluation and analysis of data shows there are mainly four types of judgment about soundscape:1) High Soundscape, but acceptableThere is a deep thought about the sound in this category of soundscapes, a decision of having the role and sinking in the voice of the activity. This case related often to other aspects of the acoustic preferences of the listeners. Although participants sometimes like silence, but they really like being around other people and enjoy from the dialogue with them. The live music is one of their main methods and preferences for the leisure time. Although, the live music events are noisy and controversial, but these events are also very heartfelt to them and they are not afraid to share his private space.
    2) High soundscape and unacceptableThe largest category of reactions to the negative effects is unwanted interferences. These sounds are usually loud noises and stimulating such as sirens, cars and motorcycles horn. Reactions and the main reasons for this interference are more complex and extensive than they seem. Initially, those sounds were considered likely that someone could generally expect the irritation from them, but they are considered as an inseparable part of the soundscape. The Police and ambulance sirens are some examples of non-irritated "irritation", although, the sirens are certainly louder and more irritating, and especially they are designed for people attraction, but the sounds of the horns are much more persecutor.
    3) Calm soundscape and acceptableDesirable and calm environments have been generally described by joy or peace feeling. Many phonetics researches have been focused to generate quiet environments and have achieved a relative success as well. These researches are generally focused on the urban parks and their potential and bracing nature. It seems also that there is very little attention to the peaceful places that are not the urban green spaces. In contrast, very few people have been used in the study of the urban parks for this purpose.
    4) Quite soundscape, but dreadfulThere was only a concept for this category, places that are silent, but have a negative manner and accordingly, the loneliness and fear issues have been formed, some issues like the public subjects that are the key tools in the confronting mechanisms that the listeners use them to conflict with the spaces that have been judged as the undesirable, but silent soundscapes. The actively understanding process of these soundscapes relatively is clear. The listener wants generally a level of human passive companionship. If they fail to hear or understand someone who is around them, show their loneliness and generally use a confronting mechanism in these cases. This case is often linked to the space.
    ConclusionsIn this study using grounded theory, how the perception of sound judgment and a variety of audio available from soundscape was found in the study area. The results show that the sounscape are manifold and complex concept and people’s Perception of different factors affecting the environment is Mnazrsvty on their overall satisfaction. Consequently, in evaluating Soundscape according to the emotions of each person and the background of their social and cultural is very important, so that in case of providing satisfaction, a sense of comfort created in person, and if not satisfied, if a person's ability to control the environment not by ignoring the noise, vandalism and leaving phenomenon will occur.
    Harvest information by memory correspondence and interviews within the study, it was concluded that when " threshold attention" of person to enter into a soundscape to be enough, this soundscape considered and responded listener in the way of his judgment about soundscape impressive. The changes range of the soundscape is “high, but acceptable”, “high, but unacceptable”, “calm and acceptable” and “the quiet soundscape but dreadful.” The most important voices that can be heard from the city are unpleasant sounds such as traffic voice, construction, street factories and repair shops, neighbors loud music sound, uproar sounds and so on. Gray voices have created some brown fields that have been surrounded into the spaces between the buildings.
    Here the main question would be "how to apply the results of the evaluation soundscape design and urban planning in the area to be used?" Since urban planning based on the location information, using GIS are different models for the future, proper planning in order to improve the environment. Thus, sounscape evaluation purposes in the study area from theory into practice is more closely coordinated.
    Per Hedfors used Ian Mc Harg method of landscape analysis to evaluate soundscape maps. In this regard, the researcher stated that the method can be combined with a clear map to show different aspects of the same soundscape. soundscape layer (sonotope) proposed as one of the information layers in planning urban soundscape. To define the existing Sonotops, the expected aural modes of the users should be considered about the relevant locations. Expected activities in their place are very important due to the land use in the planning or designing the acoustic and appropriate conditions. A list of available acoustic resources can be drawn based on the land use plan. The planning resource can be allocated to the new places in the soundscapes. Therefore, the acoustic fields map can be identified through all acoustic, effective resources in the area. Nowadays, the common method of the description of the acoustic fields for one or more acoustic resources to design or understanding is often limited to the sound intensity feature.
    Keywords: Sound, District 12, Soundscape, Ground Theory, NVivo
  • Vahid Amini Parsa, Ahmad Reza Yavari *, Athareh Najadi Pages 285-301
    Despite conservation action in the protected areas, land use changes (LUC) occur within these areas. These changes rise from several drivers especially socio-economic driving forces. This research aims to analyze relation between LUC and socio-economic variables in Arasbaran Biosphere Reserve. In this regard, previous and current pattern of LUC over past 24 years extracted using RS techniques both for the whole area and the each of the zones within the Arasbaran BR. The correlation between the LUC and four socio-economic variables (population, occupational, literacy and household size growth rate) was analyzed through statistical analysis. Results indicated 5464.59 and 1351.07 ha deforested respectively in the whole area and the core zone during 1989 to 2013. Total degradation was about 12012.24 ha. The literacy variable was not significant and so omitted form the regression model. The remnant variables analyzed by Logistic model by enter techniques as a linear regression and so the regression model for predicting the land degradation through socio-economic variables was obtained. Despite conservation action in the protected areas, land use changes (LUC) occur within these areas. These changes rise from several drivers especially socio-economic driving forces. This research aims to analyze relation between LUC and socio-economic variables in Arasbaran Biosphere Reserve. In this regard, previous and current pattern of LUC over past 24 years extracted using RS techniques both for the whole area and the each of the zones within the Arasbaran BR. The correlation between the LUC and four socio-economic variables (population, occupational, literacy and household size growth rate) was analyzed through statistical analysis. Results indicated 5464.59 and 1351.07 ha deforested respectively in the whole area and the core zone during 1989 to 2013. Total degradation was about 12012.24 ha. The literacy variable was not significant and so omitted form the regression model. The remnant variables analyzed by Logistic model by enter techniques as a linear regression and so the regression model for predicting the land degradation through socio-economic variables was obtained. Despite conservation action in the protected areas, land use changes (LUC) occur within these areas. These changes rise from several drivers especially socio-economic driving forces. This research aims to analyze relation between LUC and socio-economic variables in Arasbaran Biosphere Reserve. In this regard, previous and current pattern of LUC over past 24 years extracted using RS techniques both for the whole area and the each of the zones within the Arasbaran BR. The correlation between the LUC and four socio-economic variables (population, occupational, literacy and household size growth rate) was analyzed through statistical analysis. Results indicated 5464.59 and 1351.07 ha deforested respectively in the whole area and the core zone during 1989 to 2013. Total degradation was about 12012.24 ha. The literacy variable was not significant and so omitted form the regression model. The remnant variables analyzed by Logistic model by enter techniques as a linear regression and so the regression model for predicting the land degradation through socio-economic variables was obtained. Despite conservation action in the protected areas, land use changes (LUC) occur within these areas. These changes rise from several drivers especially socio-economic driving forces. This research aims to analyze relation between LUC and socio-economic variables in Arasbaran Biosphere Reserve. In this regard, previous and current pattern of LUC over past 24 years extracted using RS techniques both for the whole area and the each of the zones within the Arasbaran BR. The correlation between the LUC and four socio-economic variables (population, occupational, literacy and household size growth rate) was analyzed through statistical analysis. Results indicated 5464.59 and 1351.07 ha deforested respectively in the whole area and the core zone during 1989 to 2013. Total degradation was about 12012.24 ha. The literacy variable was not significant and so omitted form the regression model. The remnant variables analyzed by Logistic model by enter techniques as a linear regression and so the regression model for predicting the land degradation through socio-economic variables was obtained. Despite conservation action in the protected areas, land use changes (LUC) occur within these areas. These changes rise from several drivers especially socio-economic driving forces. This research aims to analyze relation between LUC and socio-economic variables in Arasbaran Biosphere Reserve. In this regard, previous and current pattern of LUC over past 24 years extracted using RS techniques both for the whole area and the each of the zones within the Arasbaran BR. The correlation between the LUC and four socio-economic variables (population, occupational, literacy and household size growth rate) was analyzed through statistical analysis. Results indicated 5464.59 and 1351.07 ha deforested respectively in the whole area and the core zone during 1989 to 2013. Total degradation was about 12012.24 ha. The literacy variable was not significant and so omitted form the regression model. The remnant variables analyzed by Logistic model by enter techniques as a linear regression and so the regression model for predicting the land degradation through socio-economic variables was obtained. Despite conservation action in the protected areas, land use changes (LUC) occur within these areas. These changes rise from several drivers especially socio-economic driving forces. This research aims to analyze relation between LUC and socio-economic variables in Arasbaran Biosphere Reserve. In this regard, previous and current pattern of LUC over past 24 years extracted using RS techniques both for the whole area and the each of the zones within the Arasbaran BR. The correlation between the LUC and four socio-economic variables (population, occupational, literacy and household size growth rate) was analyzed through statistical analysis. Results indicated 5464.59 and 1351.07 ha deforested respectively in the whole area and the core zone during 1989 to 2013. Total degradation was about 12012.24 ha. The literacy variable was not significant and so omitted form the regression model. The remnant variables analyzed by Logistic model by enter techniques as a linear regression and so the regression model for predicting the land degradation through socio-economic variables was obtained. Despite conservation action in the protected areas, land use changes (LUC) occur within these areas. These changes rise from several drivers especially socio-economic driving forces. This research aims to analyze relation between LUC and socio-economic variables in Arasbaran Biosphere Reserve. In this regard, previous and current pattern of LUC over past 24 years extracted using RS techniques both for the whole area and the each of the zones within the Arasbaran BR. The correlation between the LUC and four socio-economic variables (population, occupational, literacy and household size growth rate) was analyzed through statistical analysis. Results indicated 5464.59 and 1351.07 ha deforested respectively in the whole area and the core zone during 1989 to 2013. Total degradation was about 12012.24 ha. The literacy variable was not significant and so omitted form the regression model. The remnant variables analyzed by Logistic model by enter techniques as a linear regression and so the regression model for predicting the land degradation through socio-economic variables was obtained.
    Keywords: Land degradation, Driving forces, Socio-economic variables, Protected areas
  • Akram Avami * Pages 303-316
    Ecological footprint is an index to quantify the environmental impacts of man’s life. In this research, the ecological footprint index is used to assess the environmental effects of the activities of Energy Engineering Department of Sharif University of Technology. For this purpose, the required data such as energy and water consumption and the produced wasted of the faculty are collected. In addition, to compute the indirect energy consumption caused by the transportation of the students, a questionnaire survey is performed and its results are used to estimate the annual consumption of the energy in all modes of the transportation. Finally, using the standard method, the ecological footprint index is calculated for the activities of the faculty. The results indicate that the ecological footprint of the faculty is equivalent to the 41456.37 global hectares per year that its major part is related to gas and electricity consumption of the faculty. Therefore, the reduction of energy consumption in the building will have a significant impact on the reduction of this index. Furthermore, the increase of the waste recycling as well as increase of public transportation usage are other ways for reducing this index to reach sustainability in the building. The effect of each of these solutions on the reduction of ecological footprint of the faculty is thoroughly analyzed.
    In this study, to illustrate the environmental impacts of household, commercial, and public sectors in Iran, the activities of the Energy Engineering Department of Sharif University of Technology is studied as a case study. Previously, Soleimani and Avami (2016) assessed the activity of this building using life cycle analysis method. In order to reduce emissions of carbon dioxide, low-cost methods such as efficient shadings were proposed. In this study, the activity of the faculty is studied using ecological footprint method. In addition to direct effects, the indirect effects of the faculty activities are considered as much as possible in the present study using ecological footprint index to determine the sustainability of the building.
    MethodologyGiven the complexity of the ecological footprint method, this study only refers to the operation of the building and the stages of construction and destruction are not included. The faculty environmental effects include direct and indirect effects. The direct effects are the results of energy and material consumption or waste production at the faculty site. The indirect effects are the results of the consumption of materials or energy in a place rather than the faculty site. In this study, transportation of students to the faculty conducted by various modes of transportation is among the indirect effects. In this study, the consumption of electricity and gas are calculated using electricity and gas bills for one year. Using emission factors, carbon dioxide emitted by fossil fuel consumption is calculated. The land area required to absorb this amount of carbon dioxide is calculated and finally using the equilibrium factor, the land is converted to global hectares. The water consumption is also calculated using water bills for one year. Forest land is considered as the source of water production and annual consumption of water is converted to the forest land. Finally, the equilibrium coefficient converted it into global hectares. Concerning the fuel consumption related to the required transportation for the students, a questionnaire survey was performed among them in the faculty. In this way, the number of students from any mode of transportation and kilometers traveled by each mode of transportation are calculated. Using the results of this survey, per capita fuel consumption calculated for each mode of transportation as well as the annual fuel consumption of each mode is calculated and converted to global hectares similar to energy consumption of the building. At the end, the total ecological footprint of the faculty is obtained by the sum of values.
    Discussion of
    Results
    Table 1 shows the summary of results.
    Table 1: summary of the results of ecological footprint of the activities of the department
    Energy consumption of faculty Waste production
    Infrastructure land Energy consumption of transportation
    natural gas electricity Water Plastic Paper Riding BRT Subway
    Ecological footprint (gha /year) 87.24310 3.15593 97.5 5737.0 574.0 377.1 147.1512 7.7 86.23
    According to the results, most of the ecological footprint is caused by the consumption of energy at the department. In order to assess the potential of reducing the ecological footprint, the ecological footprint of electricity and gas consumption of the faculty is calculated assuming global average values for electricity and gas consumption per capita in two different scenarios. In scenario 1, the gas consumption of the building is reduced and assumed the same as the global gas consumption per capita. This value is added to the current electricity consumption of the faculty. In scenario 2 electricity consumption is calculated by assuming the global electricity consumption per capita and its value is added to the current gas consumption of the faculty. According to the results, the ecological footprint caused by the energy consumption of the faculty in scenarios 1 and 2 will reduce 14.3% and 20.7% respectively.
    The major part of the waste products is the paper and the plastic. The recycling rate of the plastic and the paper in Iran are estimated as 9% and 2%, respectively. While these values for Europe were estimated as 69.2% and 71.7% in 2014, respectively. The increase of recycling rate for the plastic and the paper will reduce the ecological footprint of wastes. The major part of the ecological footprint of the transportation is related to private cars. The use of public transportation by students significantly reduces the ecological footprint of transportation. Replacing the private cars with the subway and the BRT reduce the ecological footprint of the transportation 93.4% and 77.8%, respectively.
    ConclusionIn this study, the environmental impact caused by the activities of Energy Engineering Department of Sharif University of Technology, was studied using the ecological footprint method. The results indicate that the total ecological footprint of the faculty is 41456.37 hectares per year that its major part is related to gas and electricity consumption of the faculty. Thus, the reduction of energy consumption of the building will reduce this index significantly. Moreover, increasing the recycling rate of the wastes and using public transportation are the other solutions of reducing this index to reach sustainability.
    Keywords: Environmental Impact Assessment, Ecological foot print, Faculty, Energy consumption
  • Ebrahim Anvari *, Samaneh Bagheri Pages 317-327
    One of the main objectives of the country's economic growth may achieve this goal, lead to environmental pollution. Kuznets hypothesis test paper for the first time in two models with generalized method of moments for OPEC's findings. The Environmental Kuznets Curve hypothesis for OPEC countries, a generalized method of moments for the period 1992-2013 were analyzed. As the largest share of CO2 emissions in combination, were used to test the Kuznets hypothesis. Based on the results obtained Environmental Kuznets Curve hypothesis for individual countries was not accepted in the form of both models, in fact, the amount of carbon dioxide emissions in the process of economic growth in these countries has continually increased. Growing urbanization, population growth, energy consumption and real GDP positive and significant impact on emissions in this countries. Among OPEC members, Saudi Arabia's highest carbon emissions, economic growth and population growth and the country's fourth place in carbon emissions, economic growth and population growth in the OPEC countries. Kuznets curve relationship between pollution and per capita income began developing country, shows. After a certain per capita income, pollution levels begin to decline, because the country is able to invest in more efficient technologies and new production methods, it is. This curve associated with the development of the country. In the agriculture, the country has a per capita income and low pollution. When approaching the stage of industrialization, pollution increases. At low levels of development, quality and environmental degradation continued to work activities on natural resources and the limited quantities of biodegradable waste is limited. When the extraction of natural resources and agricultural activities and industrial mutation occurs worse, depletion of natural resources and generation of waste worse. At higher levels of development, structural changes in the industries related to information and services, high technology and demand for environmental quality has led to a steady decrease in the destruction of the environment.
    In 1987 report called Our Common Future, the concept of sustainable development was raised in the debate on environment versus development, was expressed by the International Union for Conservation of Nature and in 1980 was accepted. Supporters of the idea that economic growth, growth is the only way to provide the capital necessary to preserve the environment, but paying a high price to protect the environment, limit economic growth and competitiveness at the international level and reduces employment. Sustainable development aims to improve the investment environment and policies in order to prevent degradation and protect the environment. To achieve higher economic growth, energy consumption, the CGE model includes all the macro economy and energy is part of it. In this model, all markets and services are in balance supply and demand in a particular market affect other markets and can be static or dynamic. Supply and demand as a result of consumers maximize utility and producers maximize profit associated with each other through the elimination of price markets. Criticisms of the model is that in reality, all markets are in equilibrium. Keynesian models CGE models are close. Both models are sometimes referred to as econometric models. Keynesian the effects of transitional adjustment costs associated with the policy change, pay. CGE models are the best short-term analysis of the economy. Earth is a closed system energy use is done according to the laws of thermodynamics. Waste, waste and industrial waste in general, with raw materials, fuel and food input to the economy after deducting the accumulated material, are equal. Some economists, substitution patterns and innovation to reduce environmental impacts and environmental economics were presented, but the majority believed in the conflict.
    Matherials & MethodsMODELS:LCOit = β0i β1i LCOit-1 β2i LGDPit β3i (LGDP)2it β4i LURBANit β5i LENERGYit Uit LCOit =β0i β1 LCOt-1 β2i LGDPit β3i (LGDP)it2 β4i LPOPit β5i LENERGYit Uit
    LGDP logarithm of real per capita GDP at constant prices 2005, (LGDP)2 , squared logarithm of real per capita GDP at constant prices 2005, LEnergy log of per capita energy consumption, LCO logarithm of carbon dioxide emissions, LURBAN growth of urbanization, LPOP population growth. The research period of 1992-2013 and the countries investigated OPEC countries include: Angola, Ecuador, Nigeria, Libya, Iraq, Iran, United Arabic Emirates, Saudi Arabia, Venezuela, Aljrayr, Qatar and Kuwait. All the necessary data for this study were collected from the World Bank.
    Generalized method of moments: By this method it is necessary first to estimate the model instrumental variables used in the model are specified. GMM estimator depends on the validity of the adjustment tools. This credit can test stipulated by Arellano and Bond (1991) tested. Sargan test the validity of the test instruments. Failure to reject the null hypothesis in this test shows evidence of the validity of instruments.
    Discussion of Results & ConclusionsLGDP square was not confirmed, indicating that the Kuznets hypothesis could not be verified. Kuznets curve is not inverted U-shaped in these countries. These countries are part of the Kuznets curve upward. Dirt track of these countries is still rapidly ascending curve has not come to terms Nqth return. OPEC countries Kuznets hypothesis can not be confirmed in this study. In both models the energy consumption, and carbon dioxide emissions before and after the logarithm of GDP had the greatest influence on carbon emissions. developed countries need to support the production support environment. The environmental Kuznets curve views known in experimental models. The inverted U hypothesis of a relationship between environmental degradation and per capita income there. 1) installation of equipment cleaner emissions pollution. 2) taxes on pollution. 3) use of new technologies. 4) Improving research and development in clean technologies and environmentally friendly alternative. 5) management of energy consumption in accordance with the highest efficiency. 6) use of clean energy and renewable energy use in production. urbanization Due to the positive impact on the carbon dioxide emissions can be reduced by controlling the urban population and try to prevent it from emissions of carbon dioxide gas.
    Keywords: Iran, Environmental pollution, OPEC, GMM, Kuznets Curve
  • Hadi Soltanifard * Pages 329-347
    IntroductionThe ecological benefits of green space is not limited only to absorption CO2 and producing O2, purifying air pollution, decreasing noise, improving soil condition and groundwater recharge and moderating microclimates and reducing the heat island effect in cities .But also by creation a living and dynamic system has improved urban ecological structure and function and promote the quality of the urban environment. Basically, green space is a part of urban Landscape structure which has an important influence on a wide range of ecological patterns and processes. As well as multiple social and economic benefits, Ecological value of urban green space can improve through synergies with the urban spatial structure and function. Spatial structure of landscapes is a central object of investigation in landscape ecology. This structure finds its expression in landscape pattern, which integrates both complex conditions of the natural environment. In order to landscape literature review, spatial structure is a major subset of the concept of spatial heterogeneity, usually referring to the spatial configuration of the system property. Ecological processes and the relationship between them can be identified by determining spatial configuration and urban green spaces composition. However, findings from the literature show that the quality concept was carried out by ecological and environmental variables. In particular, the quality of urban green space is defined by quantitative and qualitative factors, that if understood and analyzed properly, it can be concluded the concept of quality. Based on quality of life and attractiveness measures, it applied to urban green space when created delightful and beautiful environment for outdoor activities and provide key ecosystem functions and services as “green sources”. Strengthening ecological quality and ability provide species, nutrients and energy for “green sinks”. From ecological perspective, the explicit consideration of the quality is related to spatial structure and spatiotemporal interaction of processes in ecological research that involved the main contribution of landscape ecology to this paradigm shift. With an emphasis on structural aspects of landscape and urban green spaces, landscape ecology approach have provided a powerful tool to assess changing green patches and landscape. In this study, conceptualized framework of quality, based on landscape ecology approach and method which can facilitate the representation and analysis of changes and environmental processes and therefore, address the environmental quality and specify the requirements. By landscape ecology approach, we can interpret the effects of above-mentioned processes for environment ecological features and achieve a primarily classification of green space quality and function .According to this, the quality concept dependent on the nature of the ecological process that occurred in different level of scale, measured at the plot context analyzed in several time and displayed and represented in spatial patterns. Conceptually, landscape structure referred to spatial composition and configuration of environmental and ecological units and relationships among them. Due to the effects on ecological processes independently and interactively, the quality of landscape can be characterized by composition and configuration properties.
    Material and MethodMashhad, the capital of Khorasan Razavi, is located in the northeast of Iran at latitude: 36°18′N 59°36′E. With an area of 382 km2 and current population 2.9 million, Mashhad is the second most populous city in Iran. In recent decades, it has witnessed rapid growth, mostly because of its economic, social and religious attractions. Due to the physical development of Mashhad in most areas, urban green spaces have been replaced with different buildings, so it is necessary to study urban green spaces in term of quality. Based on the divisions of Mashhad Municipality, it has 13 regions, which each of them, has different area, population and green spaces types and conditions. As quantity, Table 1 shows distribution of green space and urban parks.
    Data processing and green space distribution mapSatellite images were utilized to derive urban green space maps. The detail of satellite image data (Landsat 8 ETM) used in this study obtained from the U.S. Geological Survey (USGS), dated on 21st June 2014. All image processing, classification and GIS analyses were performed using ENVI 4.7 software and Arc GIS 10. To provide a green space map, the unsupervised classification method was used to generate patch layer map (i.e., a polygon layer) in ENVI 4.7 software environment. Types and features were created based on integrated land use map and calculating and extracting the normalized difference of vegetation cover index (NDVI). To obtain a green spaces distribution map, the NDVI map was rectified and geo referenced by the Arc GIS 10.
    Landscape metricsTo select and application the landscape metrics, previous studies have introduced landscape metrics according to objectives and methodology of research. Although, a series of landscape metrics, have been developed to characterize the spatial patterns of landscapes and to compare ecological quality across the landscapes, however, the number of metrics can be used in evaluating the ecological quality, but not all landscape metrics can easily be classified as representing landscape composition or landscape configuration. For example, mean patch size and patch density of a particular patch type reflect both the amount of a patch type present (composition) and its spatial distribution (configuration).
    Rank and TOPSIS methodFor ranking and assessment of ecological quality, one of the MCDM methods named TOPSIS has been applied in this research. In this section, TOPSIS method is explained. TOPSIS (Technique for Order Preference by Similarity to Ideal Solution), developed by Hwang and Yoon, is one of the MCDA/MCDM methods for resolving real-world decision problems satisfactorily.TOPSIS attempts to indicate the best alternative that simultaneously has the shortest distance from the positive ideal solution and the farthest distance from the negative ideal solution. The positive ideal solution is a solution that tries to maximize the profit criteria and minimize the cost criteria, whereas the negative ideal solution is just opposite to previous one. The positive ideal solution is composed of all the good values attainable of criteria, whereas the negative ideal solution consists of all worst values attainable of criteria. In the TOPSIS method, precise scores that each alternative receives from all the criteria are used in the formation of a decision matrix and normalized decision matrix. By taking into consideration the rates of all attributes, positive and negative ideal solutions are found. By comparing the distance coefficient of each alternative, the preference order of the alternatives is determined.
    Results and ConclusionUrban green space has many usages and benefits on quality of human life. The results indicate that green spaces of Mashhad have no adequate relative frequency and patches of green spaces have undesirable conditions in terms of spatial composition and configuration. Now it has no enough extent and continuity for providing ecological services and improving ecological quality. Appropriate distributions of patches are recognized in these areas, proximity of patches is extremely uniform and there is heterogeneous distribution of patches. There is no appropriate distribution of green space patches in other regions of the city; green spaces patches have been distributed non-uniformly and heterogeneous. Most patches are small and fragmentation is recognized, there are no appropriate ecological conditions, therefore there would be no appropriate ecological quality. Ranking ecological urban areas is done with TOPSIS. The results of this study showed that the best quality ecological area is 5 Mashhad And area 12 have the most undesirable ecological quality.
    Keywords: TOPSIS, ranking, Ecological quality, Landscape, Urban district of Mashhad
  • Mostafa Mohammadi Dah Chashmeh *, Fereshteh Shanbehpour Pages 349-364
    Environmental pollution over the past three decades has attracted worldwide attention, in the meantime, the issue of noise pollution in cities as widespread problem, but poses greater countries respectively. However, in the age of innovation and equip them to become cities aspects of emerging technologies, is part of the well-being of citizens, but today the car of a significant contribution from the comfort and safety of its citizens is denied. Noise pollution is a growing problem in urban ecosystems that discomfort with the voice of citizens, as loss-inducing factor for mental health, mental and physical well known. Noise is the one of the most important environmental pollutants in urban areas, which is the development of technology. After various aspects of life in today's mechanized world, in various forms are considered disruptive acoustic comfort. Rapid Urbanization and the changing nature of urban functions, population density, changing residential patterns, transport, industry and urban rise ... and rise to great challenges with regard to noise pollution is relatively emerging. Acoustic comfort generally have two sources of industrial and non-industrial city. Royal believes that the most important factors in making urban acoustic comfort by streets and highways within the city include traffic volume, traffic composition, speed of movement, Flooring and slope of the street, intensity and wind direction, away from buildings and streets is. However, the scale of the world's most prominent sources of urban noise include road traffic, railways, construction, industry, noise from construction activities are. However, from the perspective of urban planning, requirements and considerations urban location and type of establishment of the most important factors affecting comfort or noise pollution is sound. In fact, the city consists of a set of land use types and their relationships are. In today's metropolises, in addition to multiple electronic products (at home, at work, in the streets, public places, etc.) industries, workshops, shopping centers, streets, sports centers and all construction activities and noise as a source of jobs pollution and discomfort are sound. The land use planning in order to provide the spatial distribution pattern of urban vocalizations operations is a top priority for city planners. traffic problems of environmental issues, especially noise pollution suffered.
    Method
    The dominant approach to research, analyze location. According to the dominant approach, banks provide research data and user separation, the first step of this article. including the local arteries and arterial primarily secondary (second stage) was carried out and then the map acoustic comfort (phase III) of the composition of the maps using Fuzzy Overlay analysis and operator SUM, for urban areas was obtained Ahvaz. The analysis in this part of the sound (dB) predictable per user, based on existing standards.
    Discussion
    Commotion and noise is an integral part of modern life and modern overnight. Our ancestors lived in a more quiet environments and exposed to the sounds were softer. Spatial analysis in this study are considered in three dimensions.
     The first dimension, analyzing the results in urban areas. The following map was prepared to measure acoustic comfort segregated areas, where the results of the analysis indicate that the urban areas, in the District 5 district, zone 2 and zone 4 and zone two military police the area ratio (0/827), the district 1 area three, four regional areas 1 and 4, district 4 area, five, six regional district 1, district 4 area seven, area 1 and area industrial by a factor of (0/720) region eight-noise ratio is very high compared to other areas and low acoustic comfort in these areas respectively.
    The second dimension, spatial analysis in the metropolitan area of Ahvaz. In Zone Two (0/782) and the six (0/767) than other urban areas, the average coefficient of noise pollution is more and these areas are less acoustic comfort. The main reasons for the high level of noise pollution in these areas can be pointed to the presence of contaminants user and businesses.
    After the third, topical analysis. Among the selected indicators involved in noise pollution, heavy industry, passenger terminals, workshops annoying, multiple workshops, the military-disciplinary and cross the road network (motorways and main roads), the most important pollutants are jobs that foreclose it is comfort. Such as such as: railways in the region of six, Ahvaz airport in the region three, there are numerous workshops in six regions, including (workshop stonework in the region, six, and eight in the welding workshop, etc.), Takhti stadium in four and seven revolution in the region, a regional market (including fruit market, electronics market, etc.), the center of the military police in the area, Karoon industrial area in region seven, a large number of industries such heavy (Flour Khuzestan, Golriz Company, Inc. Covenant Nasr, pipe factory, etc.) in the region of six, highway crossing zones two and six and seven and eight regions and passenger terminals located at the end of the street revolution the six-pointed Khorramshahr in the region .
    Conclusions and Solutions :Research findings indicate that, 4-2 District (Area 4 in Region 2) by a factor of place (0/879) and 1-6 area (Area 1 in 6) by a factor of (0/807) of the lowest comfort 1-5 have audio as well as areas (area 1 in 5) and 5-4 (zone 5 in region 4) had the highest coefficient of acoustic comfort. Also, findings have shown that the establishment of incompatible land uses in the metropolitan area of the main reasons for high pollution in these areas has been poor audio sound and comfort.
    In order to enhance the acoustic comfort factor in Ahvaz Metropolis is suggested that you first: Accounting and transfer of units and workshops disturb the six metropolitan region of Ahwaz (welding, turning, rough and repair shops) out of town, Second: the implementation of the Plan annoying jobs (collection of hawkers especially from central and transfer to a suitable place), Third, the development of green spaces in metropolitan areas of Ahvaz using two and six plant species suitable environmental conditions areas, Fourth, reform of network traffic engineering in order to avoid the heavy traffic and increase user and create facilities such as public parking in the area and finally, the fifth Decentralization of downtown and core services in the areas of second and third degree.
    Keywords: Acoustic comfort, Noise pollution, Location Quotient, Metropolis Ahvaz