meghdad pirsaheb

Toluene is one of the most important volatile organic compounds that threaten human health and introduce many environmental problems. Therefore, the present study aims to determine the performance of a biofilter based on pine cones/compost to remove toluene vapors from polluted air streams.

In this research, a biofilter with a volume of 19.468 L was designed and built. The biofilter bed consisted of two parts 26 cm in height and packed with a mixture of compost and pine cones in 1:1 volumetric ratio. After inoculating the bed with sludge from a municipal wastewater treatment plant and making it compatible with toluene, the performance of the biofilter in different parts of the bed was investigated at the inlet toluene concentrations of 2.5-5.5 g/m3 and Empty Bed Retention Times (EBRTs) of 1.3, 1.7, and 2.43 min. Also, the results were analyzed statistically.

At EBRT of 2.43 min and different inlet toluene concentrations of 2.5-5.5 g/m3, the removal efficiency reached 100 percent. Also, the removal efficiency decreased with the reduction of EBRT. The results showed that removal efficiency was higher in the first part of the biofilter bed relate to the second part. At an inlet toluene concentration of 2.62 g/m3 and EBRT of 1.7 min, the maximum elimination capacity (ECmax) of 2.74 g/m3.min was obtained.

In all experimental conditions the outlet concentration of pine-cone/compost biofilter was below the WHO standard (260 µg/m3). Also, the high elimination capacity of biofilter verified its capability toward toluene removal from polluted gas streams.

It is important to determine the quality of the compost to use compost properly. The aim of this study was to determine the effect of mixing ratio of bulking agent on stability and maturity indices in poultry waste compost.

Two piles of sawdust mixture with poultry wastes and volume ratios of 1:1 (W1) and 2:1 (W2) were prepared by Windrow method and a pile containing poultry manure was used as control (W0). In order to determine the stability and maturity indices in compost, the most important physicochemical and biological parameters were studied.

The thermophilic phase lasted about 7 weeks for W1 and about 4 weeks for W2. The initial C/N ratios in the W0, W1 and W2 were 27.10, 31.40 and 56.24, respectively, which eventually reached less than 20. The reduction of organic matter in the three piles was 8.30%, 62.59% and 85.53%, respectively. The thermophilic phase caused a sharp decrease in the population of indicator and pathogenic microorganisms in all piles. The highest dehydrogenase activity in W1 pile was 2.95 mgTPF/gDW.h and by decreasing temperature until the last day, its value decreased to 0.29 mgTPF/gDW.h.

The best ratio for mixing sawdust with poultry manure was 1:1 (v:v). Microbial and enzymatic activities are useful parameters for monitoring poultry composting process and determining the rate of compost stability, and the use of this compost in agriculture will improve soil quality.

 Journal club (JC) is an accepted method to improve the knowledge of researchers by reviewing and discussing scientific texts and could also be effective in enhancing the quality of teaching and research in educational settings.

 The present study aimed to evaluate JC meetings from the perspective of postgraduate students in Kermanshah University of Medical Sciences (KUMS) in Kermanshah, Iran based on the CIPP evaluation model.

 This descriptive-analytical study was conducted on 62 postgraduate students selected from the schools of health, nutritional sciences, and food industry of KUMS in 2019. The participants were selected via convenience sampling. Data were collected using a self-report questionnaire. Data analysis was performed in SPSS version 16 using bivariate correlation, one-way ANOVA, and t-test.

 Positive, significant correlations were observed between the CIPP domains. In addition, the grade point average of the students had positive, significant correlations with the input and process domains. The items of the input domain regarding the relevance of the papers regarding the current issues of the field of study, appropriateness of the time of the event, and need to participate in JC meetings received the lowest average percentage of the maximum achievable score.

 According to the results, careful planning is required for the implementation of JC meetings by taking into account the relevant papers regarding the current issues of the field of study and time of the event.

The presence of heavy metals in the environment due to their harmful effects on human health, regarded as a problem. Today, high-performance biosorbents for wastewater treatment containing heavy metals such as cadmium were developed and are preferable than other absorbents. The aim of this study was investigation of effect of influent concentration on cadmium removal in a fixed- bed column using adsorbent Conocarpus. Conocarpus was prepared from waste vegetable of DEHLORAN city gardens and surface structure of absorbent was investigated. In this study, the effect of influent concentration on cadmium removal wasinvestigatedand Adams- Bohart  and Thomas models were used to the column adsorption modeling. Physical characteristics results showed that the adsorbent has deep pores and complex, intricate, uneven and irregular surface of filamentary structure. The results of breakthrough curves review showed that in higher concentrations, breakthrough time of bed was decreased. breakthrough curves slope increased and breakthrough volume decreased with increasing initial cadmium concentration. Also Adams- Bohart  model has a better fit of the column data

The main purpose of this study was to evaluate the effects of irrigationwith polluted water on soil properties in two water treatment as river water and well water during two years on Gharesoo River located in Dorodfaraman district, in 20 km south of Kermanshah. This study was performed in three soil layers 30, 60 & 90 cm with three replications in a randomized complete block design. Different soil properties including gradation curve, coefficients of uniformity (Cu) and curvature (Cc), saturation hydraulic conductivity (Ks) and other parameters such as bulk and practical density (ρb& ρa) and porosity (η) were determined. The results of statistical analysis showed that there was no uniform trend between various parameters. Using the polluted water caused a significant difference at 1% level on saturated hydraulic conductivity and uniformity coefficient at 5% level on curvature coefficient but on the other soil properties, no significant difference was found. Gradation curve of contaminated water had been transferred to the lower and right that this represented an increase of particles size. Also, the use of contaminated water increased uniformity and curvature coefficients then it improved these coefficients and the soil was more non-uniform. The results showed that irrigation with polluted water in loamy soil increased saturated hydraulic conductivity ratio but it decreased bulk and practical density significantly. It can be concluded that the use of polluted water increased the soil porosity.

The presence of heavy metal in water resources is the cause of many environmental pollutions. This study was carried out with the aim of investigating cadmium removal from aqueous solution using sugarcane straw nanostructure. In this study,the effects of operation conditions including pH, contact time, adsorbent loading, and initial ion concentrations were examined.
The absorption-desorption process was also carried out in five cycles. The results showed that optimum pH for cadmium adsorption is 5, the removal percentage became 94.5 %. The equilibrium time after 10 minutes obtained. With an increase in adsorbent dosage from 0.1 to 0.5 g, the removal percentage from became 88.8% to 94.5% increased. the increase of adsorbent dosage from 0.5 to 2 g did not have a significant effect on removal percentage.
With increase in Cd concentrations (5, 10, 15 and 20 mg/L), removal percentage decreased from 96% to 90%. Comparing the adsorption isotherms showed that the Langmuir model, with R2 value of 0.995 had a better fitting and description of adsorption data than other models. The results of the desorption experiments showed that sugarcane straw adsorbent could reused up to 5 cycles. The result of this study showed that sugarcane straw nanostructure is an effective adsorbent for cadmium removal from aqueous solution.

Heavy metals are recognized as one of the most toxic groups. They enter the food chain through the waste disposal into the water and environment. This study was carried out with the aim of investigating cadmium ions removal from aqueous solution using conocarpus nanostructure. For this purpose, conocarpus was grinded to nano-size by the ball mill. The effect of experimental parameters such as pH, time, adsorbent dosage and initial concentration of cadmium were studied in batch system. The PSA, FTIR and SEM tests were used to determine the absorbent characteristics. The imaging of adsorbent indicated that surface of conocarpus had many deep pores, which represents the better adsorption of cadmium. 8.5% of adsorbent particles were in the range of nanoparticles and 91.5% of them were in the range of nanostructure. The results showed that optimum pH for cadmium adsorption is 6 and the maximum removal efficiency and adsorption capacity of cadmium are 80.9% and 0.86 mg/g., respectively. Comparing the adsorption isotherm and kinetics models showed that the Langmuir and Ho models, with R2 values of 0.998 and 0.990 respectively, had a better fitting and description of adsorption data than other models. The study showed that conocarpus nanostructure is an effective adsorbent for cadmium removal from aqueous solution.

Crisis of renewable water resources and rising demand for access to fresh water in arid and semi-arid countries is increasing. Therefore, it is indispensable to conserve water resources with high quality for urban purposes and drinking and use water resources with lower quality (such as treated wastewater) for other purposes such as agriculture and industry. In these conditions, having adequate information and local data in different parts of the world is essential. Thus, the main purpose of this study was to investigate the effects of two-year long-term irrigation with treated municipal wastewater in comparison with well water (as the control treatment) on the physical properties of soil. The soil physical properties were measured in three layers, each with three replications, and included saturation hydraulic conductivity (Ks), soil moisture characteristic curve, moisture content at field capacity (θFC) and permanent wilting point (θPWP) as well as “available water”, bulk and practical density, and porosity of the surface soil to depth of 90 cm . The study was conducted using a two-year split plot design. The rsults of statistical analysis showed that there was no uniform trend between various parameters and the influence of irrigation treatments at different depths of soil parameters were different. Results showed that the soil Ks in treatments irrigated with wastewater increased, compared to the control treatments, by 109%, 25%, and 75% in depths of 0-30, 30-60, and 60-90 cm, respectively. In addition, application of treated wastewater caused increase in the soil moisture content at θFC and θPWP point, but reduced the amount of total available water content. The effect of irrigation with treated wastewater decreased surface soil bulk density and increased its practical density. Also, the soil porosity in the 0-30 and 30-60 cm layers was lower compared to the control treatment, but was higher in 60-90 cm layer. Generally, it can be concluded that the use of treated wastewater improves soil physical conditions, but the application of untreated sewage water and TWW for irrigation is not recommended for edible crops.

The most effective issues in biolog ical processes of wastewater treatment are appropriate selection of bio-kinetics issues. Therefore, the goal of this study is to review the operation, to determine the kinetics parameters and to model the biological process of the activated sludge unit of Qods hospitals wastewater treatment plant in Sanandaj, Iran.
This research is a descriptive sectional one which is conducted in the laboratory of Sanandaj wastewater treatment plant during 3 months in the 2011.As a result, a total of 100 samples were taken from raw wastewater, pond aeration, secondary effluent sludge and returned sludge. In each sample, COD, MLSS, TSS, VSS, discharge of raw sewage, F/M (on a daily basis), and BOD5 (two times a week) were measured.
Findings: The results from this study showed that the mean BOD5, COD, TSS in the secondary effluent were 39±11.9, 102±23.6 and 53±30 mg/l, respectively, and the mean of kinetics parameters of K, KS, Y, Kd, and µmax were 2.39±0.14, 36.7±5.97, 0.188±0.028, 0.04±0.01 and 0.39±0.017 respectively.
Considering the intended goal (determination of kinetic coefficients) the overall efficiency of the activated sludge system was obtained to beinappropriate.

One of the most significant factors when reusing wastewater in agriculture is microbial quality. The present study assessed the efficiency of the Sarpol-e-Zahab and Paveh treatment plants, an extended aeration–activated sludge system and that of Qaser-e-Shirn, a constructed wetland, in removing protozoan cysts and parasite ova from municipal wastewater for the purposes of reuse in agricultural irrigation. In this six-month study, samples were collected weekly from influents and effluents of three wastewater treatment plants (WTPs). A total of 144 samples were examined by applying a modified Bailenger method using the McMaster counting slide with a pore volume of 3.0 ml. Data were analyzed using SPSS version 16. The results revealed that the mean removal efficacies of parasite ova and protozoan cysts for the constructed wetland were 99.7–100% and 100%, treatment plant of Paveh 97.5–100% and 100%, treatment plant of Sarpol-e-Zahab 99–100% and 100% respectively. There WTPs showed significant differences in their removal parameters (P

Increasing use of pesticides and improper methods of sewage disposal will cause water resources pollution and extremely damaging effects on the environment. This study aimed at Performance of granular activated carbon to diazinon removal from aqueous solution and assessing the relationship between COD and diazinon concentration.
This study is as a cross - sectional and work was carried out in lab-scale. Firstly, diazinon concentrations 1, 5, 10, 20, 30, 40, 50, 100, 150 mg/l were prepared from Stock solution (1000 mg/L), and then their COD were measured. Optimum pH for 2-4-D removal was determined and its absorption rate in different concentrations was measured.
Findings: Results showed a relationship between COD and concentration. On the other hand, COD removal increased with passage of the time, so that maximum removal 88% at contact time of 50 min observed. Optimum pH for all concentrations was determined to be.
Discussion and According to present study it can be concluded that activated carbon have be high performance of diazinon removal from water. In addition, a significant relationship was observed between COD and diazinon concentration, so that direct.

Building materials and the ventilation rate of a building are two main factors influencing indoor radon and thoron levels (two radioactive gases which have the most important role in human natural radiation exposure within dwellings).
This analytical descriptive study was intended to determine the relationship between indoor radon and thoron concentrations and the building materials used in interior surfaces, as well as between those concentrations and the type of ventilation system (natural or artificial).
102 measurements of radon and thoron levels were taken from different parts of three hospital buildings in the city of Kermanshah in the west of Iran, using an RTM-1688-2 radon meter. Information on the type of building material and ventilation system in the measurement location was collected and then analyzed using Stata 8 software and multivariate linear regression.
In terms of radon and thoron emissions, travertine and plaster were found to be the most appropriate and inappropriate covering for walls, respectively. Furthermore, granite and travertine were discovered to be inappropriate materials for flooring, while plastic floor covering was found suitable. Natural ventilation performed better for radon, while artificial ventilation worked better for thoron.
Internal building materials and ventilation type affect indoor radon and thoron concentrations. Therefore, the use of proper materials and adequate ventilation can reduce the potential human exposure to radon and thoron. This is of utmost importance, particularly in buildings with a high density of residents, including hospitals.

Integrated environment, health and safety (EH&S) Management System uses a new and systematic approach to explain the interaction between health, safety, and the environment. It is a useful tool for addressing defects, risks, and accidents and for providing a prevention-based system. The aim of this study was to establish a suitable procedure to evaluate the EH&S conditions of environmental health laboratories, and a case study of the Environmental Health Laboratories of Kermanshah University of Medical Sciences was conducted in 2015. In this study, an evaluation proposal was derived using standard checklists from OSHA and the University of Colorado (including EH&S and legal resources and Iranian standards). Based on these standards and recommendations, a final protocol was prepared and was used by the Department of Environmental Health Laboratories, Kermanshah University of Medical Sciences, Kermanshah, Iran, 2015. The study sample included 28 undergraduate and graduate students of engineering and environmental health and three persons with laboratory expertise. These people were working in the chemistry, microbiology, reference labs, and the pilot room. The results of the study showed that a prepared checklist could be a useful tool to assess the EH&S conditions of environmental laboratories. Categorizing the results for further corrective acts provided an opportunity to plan a future approach and to prevent undesired accidents and health hazards. Evaluation of the studied cases showed that the chemistry, microbiology, and reference labs had poor environmental conditions. The health status of the chemistry, reference, and microbiology laboratories as well as the pilot room was poor. The microbiology laboratory had an optimal safety status; the chemistry and reference laboratories, a moderate safety status; and the pilot room, an undesirable safety status. Finally, the lack of an integrated EH&S policy was the major defect observed at the laboratories, and the efficacy of the derived protocol for evaluating the EH&S conditions of the laboratories was well documented.

The use of raw wastewater or effluent from inefficient wastewater treatment plants can result in an outbreak of parasitic diseases in a community. The aim of this study was to measure the parasite contamination of raw wastewater in Qasr-e-Shirin and evaluate the performance of a constructed wetland system in removing this contamination. This descriptive cross-sectional study was conducted over the course of 6 months (24 weeks), with a total of 48 samples selected to be tested. Every week a sample was taken from the raw wastewater of the influent and effluent. To identify parasites on the basis of a modified Bailenger method, parasitic analysis was conducted using a McMaster counting slide. The results showed that the minimum, average, and maximum number of all parasite eggs in the raw wastewater of Qasr-e Shirin was 0.08, 35.85, and 167.8 per liter, respectively. The minimum, average, and maximum number of protozoan cysts was 0, 19.95, and 75 per liter, respectively. In the wetland system of Qasr-e-Shirin, removal levels of protozoan cysts and parasite eggs were found to be 99.7 ± 0.23% and 100%, respectively. Because of parasitic wastewater contamination in Qasr-e-Shirin, outbreaks of parasitic diseases in this city are important issues. On the basis of the results of this study, constructed wetlands are very effective in removing parasitic contaminants. In addition, in term of parasite nematode eggs, the final effluent was consistent with the standards for reusing agriculture irrigation (1≥ number per L).

Urbanization, industrial development, mining, and agriculture all contribute to the pollution of the environment. Water resources are considered to be a vital part of the environment and are especially impacted by pollution from heavy metals. Because of the detrimental effects of heavy metal contamination on public health, the present study reviews previous research on Iranian water resources in terms of concentrations of heavy metals in the last 20 years. This study will be the first step toward managing and solving this critical public health concern. This study is a systematic review that aims to investigate the concentrations of heavy metals in Iranian surface and groundwater resources. Iranian and non-Iranian databases, including Iran Medex, SID, Google Scholar, Scopus, and ISI Web of knowledge, were reviewed for papers over the last 20 years from 1992 to 2012. Thirty-nine relevant papers were analyzed. Most studies reported the concentrations of heavy metals to be above the standard level. In groundwater resources, concentrations of Pb and Cd are above medium level, whereas in surface water resources, concentrations of Pb, Cd, Ni, Cr, and Fe are above the standard level. Accordingly, the increase in heavy metal concentrations is due to the pollution of mining and related industries, and also the excessive use of pesticides in agricultural land, and so on. Regarding high the concentration of heavy metals in several areas, particularly around industrial and agricultural sites, the government should administer strict environmental regulations to reduce the concentrations of these metals in order to protect the environment and public health from damage; otherwise, irreparable damages will occur to the environment and public health.

The main purpose of this study was to assessment the effects of long-term irrigation with pollutant water on soil physical properties of two water treatment as pollution water and well water during two years (2013 & 2014) on Gharesoo River located in Doroodfaraman district, in 20 km south of Kermanshah. This study was performed in three soil layers 30, 60 & 90 cm with three replications in randomized complete block design. In this study, soil physical properties including saturation hydraulic conductivity (Ks), soil moisture characteristic curve and parameters (θFC, θPWP & AW), bulk and practical density (ρb & ρa) and porosity (η) were determined. The results of statistical analysis showed that there was no uniform trend between various parameters. Using of the pollutant water was caused a significant difference at 5% level on saturated hydraulic conductivity but on the other physical properties of soil no significant difference were found. The results showed that irrigation with pollution water in loam soil increased saturation hydraulic conductivity ratio significantly but it decreased the moisture in FC, PWP and also bulk and practical density. It can be concluded that the use of pollutant water increased the soil porosity.

Due to the present water shortage and environmental problems associated with industrial effluent, investigation of novel treatment technologies is an essential approach. Being a highly toxic chemical of asphyxiating characteristics, cyanide is seen as a major environmental pollutant in a wide range of industrial effluents. The present study aimed to address the adsorption and photocatalytic degradation of cyanide using activated fly ash and TiO2/UV. To investigate the removal efficiency of cyanide, two sets of experiments were designed. First, cyanide was absorbed by activated fly ash and degraded via a photocatalytic process, individually. Second, simultaneous adsorption and degradation was examined. The removal efficiency of cyanide by modified fly ash (MFA), TiO2/UV, and their combination (MFA-TiO2/UV) was 76.1%, 81%, and 86.6%, respectively. Optimal conditions for the combination of activated fly ash AFA-TiO2/UV were contact time of 6 hours, temperature of 100 °C, and AFA: TiO2 ratio (w/w) of 1:1. Under these conditions, a maximum removal rate of 92.4% was obtained when 1.2 g of MFA/TiO2 was used with a pH value of 3 in the presence of UV light. Based on the results of cyanide removal, it can be concluded that the combination of adsorption and photocatalytic degradation with MFA-TiO2/UV can be utilized to improve the removal of cyanide from wastewater.

The endemicity of chronic hepatitis B infection in Iran is 2% to 7% among other mesoendemic areas in the world. In this cross-sectional study, all barbers’ population (2690 persons), both male and female, were investigated. Data collection was done by a check list. Based on the results, the prevalence of hepatitis B was 0.92%. The prevalence was high in people aged>60 years, barbers with more than 20 years working experience, non-vaccinated persons and in men. The first measure to be taken to prevent hepatitis B is continuous training program for barbers and the most effective and economical prevention method is vaccination.

Access to safe drinking water is an important means of safeguarding public health. This cross-sectional study was designed to investigate the performance of electrocoagulation in the treatment of surface waters. For this purpose, water samples were taken from the intake to the Soleymanshah-Songhor Dam. Treatment was carried out in a reactor operating in the batch mode. Experiment runs were designed using the Design Expert Software (Stat-Ease Inc., Version 6.0.6) to investigate the effects of voltage (5-25), reaction time (20-60), temperature (10-30Ċ), and rapid mixing (200-400) on the Mn (II), Fe (II), hardness, alkalinity, and turbidity removal efficiencies as a result of treatment with aluminum electrodes. After the treatment process, the study parameters and the dissolved metal content due to the dissolution of the anode electrode were measured. Maximum removal efficiencies for Fe (II), Mn (II), hardness, and alkalinity were 96.2%, 94.6%, 26.6%, and 12.2%, respectively, while turbidity reduced from 0.6 to 0.15 NTU. Moreover, the dissolved Al content in the treated sample was found to be higher than the standard limit allowed for drinking water. Thus, the electrocoagulation process seems to be effective in the removal of the investigated contaminants from surface waters. However, the factor limiting the use of this method under maximum efficiency conditions is the dissolved metal content due to the dissolution of the anode electrode, which is a significant concern for the public health. In contrast, the electrocoagulation process seems to be an efficient and safe pretreatment method using aluminum electrodes if operated for achieving optimum efficiencies.

In this study, ozone combination with a sequencing batch reactor was tested in laboratory scale for treating a soft drink wastewater characterized by high concentrations of chemical oxygen demand (COD). A bench scale aerobic sequencing batch reactor (SBR) is carried out by two stages. The system was operated under three different mixed liquid suspended solids (MLSS) concentrations (3000, 4500, 6000 mg/l). The results show that the integrated ozonation with biological process was able to achieve high removal efficiencies for chemical oxygen demand (COD), with residual concentrations much lower than the current discharge limits. Also, the process was characterized by a very low MLSS concentration. Hence, the ratio between ozone dose and the COD removal was 0.72, indicating that the removed COD was higher than the dosed ozone. Artificial neural networks (ANN) was also employed to model the COD data obtained. A network consisting of two layers of five neurons in the hidden layer was considered. Regression coefficient between experimental data and data predicted by neural networks and root mean square error (R2, RMSE) obtained 0.991, 80.36, respectively. Very low error in the network estimation confirmed validity of the obtained networks for further analysis and optimization.

During patients’ hemodialysis Circle, the amount of heavy metals in feed water to dialysis instrument and the patient’s blood are changed. The present study aims at evaluating the trend of lead, cadmium, chromium and zinc concentration in feed water to reverse osmosis, dialysis instrument and blood of hemodialysis patients in 7 hospitals of Kermanshah. A total of 42 samples of feed water, 42 samples of reverse osmosis systems permeate and 42 samples of hemodialysis instrument permeate were collected from 7 hospitals in Kermanshah. The collected samples were analyzed and the concentration of lead, chromium, cadmium and zinc were determined by using ICP (DV-Optima2100 model) according to a standard method. Furthermore, statistical analysis was carried out by using one-sample t-test to compare mean quality of feed water of dialysis instrument with AAMI and EPH standards. In addition, ANOVA test was used for comparing the results of three sample groups. The obtained results indicated that the mean concentration of lead, cadmium, chromium and zinc in feed water of reverse osmosis system (drinking water), were 18.53± 8.25, 0.706± 0.42, 86.06 ± 5.56, 112.67± 63.56pbb, respectively. Also, quantity of these constituents in the feed and permeate of electrolysis device was 18.81±5.32, 0.719±0.53, 84.25±2.46, 43.39±19.4pbb and 12.5±6.32, 1.39±0.87, 66.15±13.54, 60.38±22.39pbb, respectively. Due to obtained results, the removal efficiency of zinc and chromium by reverse osmosis system in dialysis instrument were 61.5 and 2.1%, respectively, while it was not effective in removing lead and cadmium metals. Discussion & Increasing the level of lead and cadmium in permeate water of the reverse osmosis system rather than the feed water indicated that the reverse osmosis membrane function is out of service; as a result, it is required to be washed or replaced. Decreasing both lead and chromium metals in permeate solution of the dialysis instrument revealed the addition of the amount of those two hazardous metals to the blood of hemodialysis patients, which could be related to reverse osmosis membrane deficiency and high concentration of metals in its water permeate.

Textile dyeing industries wastewaters are contain significant amounts of organic dye compounds. Presence of organic dyes in industrial effluents due to avoid light penetration into the water, impaired photosynthesis, decreased oxygen transport into the water, the solubility of gases and their toxic effects, irreparable damage to the environment [1]. So, treatment of colored wastewater of textile industries before discharging them into the environment is essential. Biological treatment processes for textile wastewater treatment is rarely used. These processes are commonly used to remove biological decomposition of organic compounds and suspended solids are effective but not efficient for the removal of dyes from textile wastewaters, because the colored compounds containing resistant and complex structures that can be done to slow down the rate of biodegradation of colors. The most commonly methods for color removal from textile wastewater are physical-chemical methods such as coagulation, flocculation, adsorption, ozonation, reverse osmosis, membrane filtration and advanced oxidation [2]. Each of these methods has advantages and disadvantages for the removal of dyes from wastewater. The main advantages of colored wastewater using coagulation and flocculation process, not the production of intermediate products that are toxic and harmful, mainly because of the color compounds in this way is not decomposed. In addition, this method is relatively high cost and performance in large scale [1, 2].The aim of the study is to evaluate the efficiency of alum and ferric chloride coagulants for wastewater treatment of textile factories. For this purpose, the effect of pH and concentration of coagulants was investigated. For this study, the coagulant aluminum sulfate (alum) (Al2(SO4)3) and ferric chloride (FeCl3) for color Crepe-Naz textile wastewater treatment plants by measuring of color, chemical oxygen demand (COD), biochemical oxygen demand (BOD), total suspended solids (TSS) and pH were used. pH values tested for the selection of optimal pH were 4, 5, 6, 7, 8 and 9 and in this study a total of 240 samples according to standard methods for water and wastewater treatment experiments were analyzed [3]. The results showed that ferric chloride coagulant for removal of TSS, COD and color compared to alum has higher efficiency, so that maximum removal of COD, and color by alum 36, 19 and 68.8% respectively, while this amount by ferric chloride is 72, 60 and 98%, respectively. The optimum pH for alum and ferric chloride coagulants, respectively 7 and 5 were obtained. The result of this study with conducted study by Joneidi and Azizi [2] was coordinated so that, in the study, ferric chloride than alum has better efficiency in removal of dye has shown. Based on the results, it can be concluded that ferric chloride coagulant for the removal of COD, TSS and color of textile wastewater compared to alum has been effective and therefore in identical conditions, its application is more preferable compared to alum.

Aerobic treatment processes with fixed growths exhibit a high efficiency not only in the removal of organic materials and phosphorus but also in the nitrification process (conversion of ammonium to nitrate) in wastewater. The present study aims to evaluate the performance of activated sludge with a submerged fixed bed in the removal of phosphorus and nitrogen compounds from wastewater. For this purpose, a reactor was initially constructed and commissioned before the activated sludge with a submerged fixed bed was loaded. A total number of 225 samples were collected from the wastewater treatment plant at Farabi General Hospital in Kermanshah to evaluate the removal efficiency of ammonia nitrogen, total nitrogen, nitrite, nitrate, and phosphate over three different retention times (2.9 hours of aerobic and 1.1 hours of anaerobic operation; 3.6 hours ofaerobic and 1.4 hours of anaerobic operation; and 4 hours of aerobic and 1.5 hours of anaerobic operation). Phosphorus, ammonia nitrogen, nitrite, and nitrate measurements were performed according to the Standard methods 4500-P, 4500-NH3, 4500-NO2, and 4500-NO3, respectively. Results showed that the highest phosphorus removal (53%) was achieved with Phase III of the system (i.e., 4 hours of aerobic plus 1.5 hours of anaerobic operation) while the highest ammonia nitrogen removal (97%) and TKN (96%) were achieved in Phase II of the system (i.e., 3.6 hours of aerobic and 1.4 hours of anaerobic operation). Significant differences (Pvalue<0.05) were observed among the mean values for the removal efficiencies of these parameters in the three retention times. The optimum time for the removal of ammonia nitrogen was estimated at 3.6 hours of aerobic and 1.4 hours of anaerobic operation and that for the removal of phosphorus was 4 hours of aerobic and 1.5 hours of anaerobic operation. Based on the results obtained, it may be claimed that the activated sludge process with the submerged fixed bed exhibits a high efficiency for the removal of phosphorus and nitrogen compounds from hospital wastewater only if the system is properly operated and maintained.