جستجوی مقالات مرتبط با کلیدواژه « effluent quality » در نشریات گروه « محیط زیست »

Hospital wastewater contains a variety of pollutants, a large amount of pathogenic microorganisms, viruses, radioactive materials, etc., which unless treated and disposed properly, can cause serious damage to human beings and the environment. The purposes of this study are to investigate the wastewater treatment and disposal conditions and the effluent quality in Guilan hospitals.In this study, besides the investigation of wastewater management conditions in Guilan hospitals with wastewater treatment plants, the sewage treatment performance was assessed in one of the hospitals. Qualitative indicators including total coliform, fecal coliform, pH, DO, BOD5, COD, TSS, total phosphate, ammonia, nitrate and silver in the effluent were assessed and the lab results were compared to the standards of Iran Department of Environment.According to statistical results, 10 out of the 34 studied Guilan hospitals have active wastewater treatment systems. Furthermore, the qualitative assessment showed that pH, COD, BOD5, DO, phosphate, nitrate, silver, total coliform and fecal coliform levels in the hospital conform to the standards of Iran Department of Environment. However, reduction of ammonia and TSS levels should be considered. A number of hospitals in Guilan do not have wastewater treatment plant and their wastewater is discharged into municipal wastewater collection systems or drains. On the other hand, a number of hospitals with wastewater treatment plants do not work properly. Therefore, it is important to consider executive decisions regarding new wastewater treatment technologies and upgrading treatment process in existing wastewater treatment plants. 

Treatment of municipal wastewater and its proper disposal is one of the most critical needs for urban services. Stabilization pond method is one of the simplified methods, low cost, and easy maintenance and operation. For evaluation of the Qorveh County Wastewater Treatment Plant, 54 samples were taken from the raw wastewater and the effluent in winter and spring seasons and 12 factors including: BOD, COD, TDS, TSS, pH, TC, FC, temperature, phosphate, nitrate, ammonia and the inlet and outlet turbidity of wastewater were measured according to Standard Methods. ANOVA and t-Test were used to analyze the data and to compare them with the national standards. The results showed that removal efficiency of BOD, COD, TSS, TDS, TC, FC, nitrate, phosphate and ammonia by Qorveh treatment plant were 81.56, 82.44, 70.81, 24.12, 99.91, 92.23,79.34, 56.51, and 96.16% respectively. The results of ANOVA aslso showed that the treatment plant performance was not affected by the season change. Comparing the amount of parameters with discharge standard determined that the values ​​of BOD, COD, TSS, TDS, TC, and FC were higher than the standard and the effluent could not be discharged into surface waters. Based on the grey water reuse for agricultural purposes, although all parameters except biological parameters were lower than the permitted level, the reuse of this wastewater without disinfection and supplementary purification is not possible due to the sensitivity and importance of health of agricultural products.

Food industries are among the main national industries allocating a significant contribution in terms of total production, water consumption, and effluent generation. Khosh Noosh company is one of the main food industry in Hamedan City that its effluent releases into the Jorghan River after treatment and finally IS USED for irrigation of agricultural lands. The aim of this study was to assess the company's effluent quality and its comparison with the standards of U.S. Environmental Protection Agency, World Health Organization and the National Department of Environment. During this study, a station from the exit of the company and the entrance to the Jorghan River was selected and parameters of pH, TSS, TDS, COD, BOD5, total coliform and fecal coliform were evaluated. The study found that there is a significant relationship between pH and the standard of National Department of Environment at 95% confidential level. However, no significant relationship was stablished between other parameters and this standard. With a confidence level of 95%, there was a significant difference between TDS and the World Health Organization and the U.S. Environmental Protection Agency standards. The correlation between chemical and biological factors in Khosh Noosh Company indicated that there is a significant relationship only between BOD5 to COD and pH and also between pH and total coliforms with 95% confidence level. While no significant relationship exists between other factors.