Health and environment
Mohsen Yazdani; Hosein Alidadi; Aliakbar Dehghan; Mojtaba Davoudi; Mahmood Dankoob; Mahmoud Taghavi; Reza Ataei; Aliasghar Navaei
Volume 26, Issue 1 , March and April 2019, , Pages 153-159
Abstract
Pistachio hull, a by-product of Pistachio processing, is a source of environmental pollution and can cause the health problems. Therefore, it must be treated by proper, sanitary and economical manners. One of the basic parameters for compost valuation is determine the amount of heavy metals. The objective ...
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Pistachio hull, a by-product of Pistachio processing, is a source of environmental pollution and can cause the health problems. Therefore, it must be treated by proper, sanitary and economical manners. One of the basic parameters for compost valuation is determine the amount of heavy metals. The objective of the present study was to determiner the concentration of heavy metals (pb, Cd, cr, Zn, Ni, Cu ) in the compost produced from mixed Pistachio Hull and livestock and Compare levels of heavy metals with the limits of international and internal standards.Material & Methods: This study is a descriptive cross-sectional that in sampling was two-stage in September 2014 and October 2015 A total from 2 composting pile , Compound sampling based ,26sample were selected. After digestion of the samples, the concentrations of metals( Pb ,Cd, Zn,Cr,Cu,Ni) by means of atomic absorption analysis and the concentration of a component in the sample based on mg / kg dw were reported.
Mohammad Taghi Ghaneian; Masoumeh Tabatabaee; Mohammad Hasan Ehrampush; Mohammadreza Nafisi; Mohsen Amrollahi; Mahmoud Taghavi
Volume 24, Issue 3 , July and August 2017, , Pages 197-203
Abstract
Background: 2,4-Dichlorophenoxyacetic acid (2,4-D) is a widely used acidic herbicide with high toxicity. So, this study was performed with the aim of investigation of 2,4-D photochemical oxidation by persulfate and UV.
Materials and methods: This study was performed in bench scale and batch condition. ...
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Background: 2,4-Dichlorophenoxyacetic acid (2,4-D) is a widely used acidic herbicide with high toxicity. So, this study was performed with the aim of investigation of 2,4-D photochemical oxidation by persulfate and UV.
Materials and methods: This study was performed in bench scale and batch condition. K2S2O8 was used as oxidant in presence of UV. In this study, effects of pH, oxidant concentration, contact time and initial concentration of 2, 4-D on the process were examined in batch experiments. The concentration of 2, 4-D was determined using spectrophotometer at 285 nm.
Results: The best results were achieved at acidic conditions (pH =3). Increasing dosages of persulfate and contact time increased the degradation of 2,4-D. However, an increase in initial 2,4-D concentration resulted in decreasing of photochemical oxidation efficiency. The maximum photochemical oxidation efficiency of 2,4-D was 96 % for a 2.5 mg/l persulfate, 10 mg/l 2,4-D, pH value of 3.0 and contact time of 240 min. The degradation of 2, 4-D by persulfate is found to follow the pseudo-first-order kinetic model (R2=0.979).
Conclusion: In this study, 2,4-D was effectively degraded in aqueous solutions by the photochemical oxidation using S2O8/UV. From this study, it seems that photochemical oxidation with S2O8/UV can be an effective process for the treatment of contaminated water with 2, 4-D.
Mansur Zarrabi; Mohammad Noori Sepehr; Mohammad Shakak; Gholamreza Ebrahimzadeh; Mahmoud Taghavi
Volume 24, Issue 4 , July and August 2017, , Pages 239-248
Abstract
Background & Objectives: Phosphorus is a common ion in wastewater treatment effluents, but excess amount of phosphate concentration in the effluent discharge accelerates eutrophication that affects many natural water bodies. Eutrophication of the water bodies is one of the most important environmental ...
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Background & Objectives: Phosphorus is a common ion in wastewater treatment effluents, but excess amount of phosphate concentration in the effluent discharge accelerates eutrophication that affects many natural water bodies. Eutrophication of the water bodies is one of the most important environmental problems. Eutrophication can lead to abundant development of aquatic plants, growth of algae and disturbance to the balance of organisms present in the water. Therefore, in present work, natural and modified yellow and red soil with EDTA was used for removal of phosphorous from aqueous solution.
Materials & Methods: All experiments were conducted in a batch system. Natural yellow and red soil and its modified one with EDTA were used as adsorbent for removal of phosphorous from aqueous solutions. Effect of various experimental parameters such as pH, initial phosphorus concentration, contact time and adsorbent mass were investigated.
Results: Results showed that the removal efficiency was increased by increasing in contact time, adsorbent mass and initial phosphorus concentration. Higher removal efficiency was observed at 150 min contact time, 10 g/L adsorbent mass, 50 mg/L phosphorus concentration and pH 5. At these conditions, about 65% of phosphorus were removed by natural soils, while 78% was removed by modified adsorbents.
Conclusion: The results of present work well demonstrate that, due to higher content of calcium, red and yellow soil is capable for adsorption of phosphorus and if they be modified with EDTA, their efficiency will be improved remarkably.
Somayyeh Rahimi; Mostafa Alizadeh; Ferdows Kord Mostafapour; Edris Bazrafshan; Edris Hosseinzadeh; Mahmoud Taghavi
Volume 23, Issue 1 , May and June 2016, , Pages 48-57
Abstract
Background & Objectives: With increasing the dairy products, particularly cheese, the problem of pollution arisen from the corresponding wastewaters and their treatment is being more serious than before. One of the used treatment methods for such wastewaters is coagulation process. This study was ...
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Background & Objectives: With increasing the dairy products, particularly cheese, the problem of pollution arisen from the corresponding wastewaters and their treatment is being more serious than before. One of the used treatment methods for such wastewaters is coagulation process. This study was done with the aim of determining optimal condition of coagulation process for dairy wastewater treatment using poly Aluminium chloride (PAC). Materials & Methods: At first, the coagulation process with PAC coagulant was used under laboratory conditions. By changing important parameters affecting the system pH (2-12) and coagulant dosage (5-100 mg/L), the decreasing of quality parameters of effluent such as Chemical Oxygen Demand(COD), Biological Oxygen Demand(BOD), Total Kjehldahl nitrogen (TKN), Total Phosphorous(TP) and Total Dissolved Solids (TDS) were obtained. Results: Experiments showed the removal efficiency ofCOD, BOD, TKN, TP, and TDS in pH 8 and coagulant dosage of 50 mg/L at 22±2 °C can be reached to 74.51, 84.81, 68.24, 65.46 and 85.69, respectively, which were the highest amounts among the pHs and coagulant dosages studied. Conclusion: The results showed that PAC coagulant is able to improve quality parameters of dairy wastewaters to standard levels. Because of availability, easy operation and acceptable removal efficiency for this wastewater type, PAC coagulant can be used for treatment of dairy industries wastewater.