Environmental Health Engineering and Management Journal

123-129

Authors: Selvaraj Suresh

Background: The presence of even a very small quantity of dye in water bodies is undesirable and affects the water bodies. Dye removal from industrial waste water is significant; hence in this study, a material that is an economical waste product was employed to test its acid dye removing capacity from aqueous solution. Methods: In this study, batch mode experiments were performed in the sorption process of Acid Red 97 (AR 97), Acid Red 114 (AR 114) and Acid Red 151 (AR 151) onto Curcuma angustifolia scales (CS). Also, the effect of process parameters like pH and adsorbent dosage was studied. The experimental data of AR 97, AR 114 and AR 151 sorption was fitted to Langmuir, Freundlich and Temkin isotherm models. Kinetic results in AR 97, AR 114 and AR 151 sorption were fitted at various concentrations to pseudo-first order, pseudo-second order, Elovich and Intra-particle diffusion model. Results: The monolayer sorption capacity of the acid dyes was found to be AR 97 (350.87 mg/g), AR 114 (202.42 mg/g) and AR 151 (168.91 mg/g). The Pseudo-second order model proved to be the best fit for the acid dyes. Boyd plot, confirms film diffusion in all acid dye sorption processes. Conclusion: The results showed higher dye removal for acid dyes at pH 2. The isotherm data, demonstrated good sorption capacity with AR 97>AR 114>AR 151. Employing the CS material in this study proves to be a potential alternative to costlier adsorbents, utilized for the treatment of dye containing industrial waste water.

137-142

Authors: Maryam Moradnia, Masoud Panahi fard, Kavoos Dindarlo , Hamzeh Ali Jamali

Background: Application of potassium ferrate is a chemical oxidation approach used for water and wastewater treatment. The aim of this study is to apply central composite design (CCD) and response surface methodology (RSM) to optimize potassium ferrate consumption in the treatment of wastewater from carpet industries. Methods: Samples in this experimental study were collected from wastewater, originating from a carpet factory. Wastewater sampling was carried out monthly for a period of two seasons. Ferrate oxidation experiments were conducted by means of a conventional jar-test apparatus. The time and speed for mixing were set with an automatic controller. Parameters of study were measured based on given methodologies in Standard method for examining water and wastewater. CCD and RSM were applied to optimize the operating variables including potassium ferrate dosage and pH. Results: Results showed that potassium ferrate concentration (A), pH (B), their interactions (AB) and quadratic effects (A2 and B2) were significant in the removal of COD, turbidity, color and TSS from carpet industries effluents. At an optimum point (COD: 160 mg/L of potassium ferrate and pH 4, turbidity: 165 mg/L of potassium ferrate and pH 4, color and TSS: pH 4.5 and 150 mg/L of potassium ferrate) removal efficiencies for COD, turbidity, color and TSS were86, 86, 87 and 89%, respectively. Conclusion: Potassium ferrate has a significant impact on pollutants decomposition and the removal of color from wastewater produced in carpet industries. This process can be employed for the pretreatment or post treatment of wastewaters containing refractory organic pollutants. CCD and RSM are suitable tools for experimental design.

151-158

Authors: Mohammad Shakerkhatibi , Mohammad Mosaferi, Khaled Zorufchi Benis , Zahra Akbari

Background: The measurement data regarding the influent and effluent of wastewater treatment plant (WWTP) provides a general overview, demonstrating an overall performance of WWTP. Nevertheless, these data do not provide the suitable operational information for the optimization of individual units involved in a WWTP. A full-scale evolution of WWTP was carried out in this study via a reconciled data. Methods: A full-scale evolution of acrylonitrile, butadiene and styrene (ABS) resin manufacturing WWTP was carried out. Data reconciliation technique was employed to fulfil the mass conservation law and also enhance the accuracy of the flow measurements. Daily average values from long-term measurements by the WWTP library along with the results of four sampling runs, were utilized for data reconciliation with further performance evaluation and characterization of WWTP. Results: The full-scale evaluation, based on balanced data showed that removal efficiency based on chemical oxygen demand (COD) and biochemical oxygen demand (BOD5) through the WWTP were 80% and 90%, respectively, from which only 28% of COD and 20% of BOD5 removal had occurred in biological reactor. In addition, the removal efficiency of styrene and acrylonitrile, throughout the plant, was approximately 90%. Estimation results employing Toxchem model showed that 43% of acrylonitrile and 85% of styrene were emitted into the atmosphere above water surfaces. Conclusion: It can be concluded that the volatilization of styrene and acrylonitrile is the main mechanism for their removal along with corresponded COD elimination from the WWTP.

165-172

Authors: Ahmadreza Yari, Hossein Jafari Mansoorian, Gharib Majidi, Ghazal Yazdanpanah , Ali Sayfouri

Background: The aim of this study was to evaluate the physical and chemical quality of groundwater in the villages of Qom province during summer 2014, and to compare the results with Iran’s Standard No. 1053. Methods: This research is a descriptive sectional study. During the investigation, one step sampling with the necessary repetitions (if necessary) was performed of each well for evaluation of physical and chemical quality of groundwater in the villages of Qom province. SPSS version 16 and ARCGIS software were employed for data analysis and data zoning respectively. Results: The average concentration of magnesium, sulfate and ammonia in wells water were higher than standard. The average concentration of fluoride was lower than the standard limit. pH and turbidity in all wells were within the standard limit but sulfate in 33.33%, ammonia in 13.33%, magnesium in 10.66%, sodium in 40%, calcium in 5.33%, nitrate in 17.33%, total dissolved solids (TDS) in 14.66% and electrical conductivity (EC) in 24% of wells were higher than the standard limit, and fluorine in 98.66% of wells was lower than the standard limit. The results of zoning in the villages of Qom province revealed that measured values at most wells were in the maximum amount in central and northeastern areas and minimum amount in southern and western areas. Conclusion: This study indicated that most of the physicochemical parameters such as fluoride in almost all villages, and sulfates, chloride, magnesium, sodium, calcium, nitrate, TDS and EC in some of the wells did not fall within the permissible limit.