Wastewater samples were collected from pulp and paper mill located in Kashipur (India) and were extracted using dichloromethane (DCM), chloroform and hexane solvents (all were HPLC-grade). The extracts were assayed fo...Wastewater samples were collected from pulp and paper mill located in Kashipur (India) and were extracted using dichloromethane (DCM), chloroform and hexane solvents (all were HPLC-grade). The extracts were assayed for their mutagenic potential using Ames Salmonella mutagenicity assay. TA98 strain was found to be the most responsive, in terms of induction factor (Mi) and slope (m) of the initial linear dose-response curve as determined by linear regression analysis up to the increasing doses indicating the presence of frame shift mutagens in the test samples. Mutagenicity of different extracts is arranged as follows: dichloromethane extracted water samples > hexane extracted water samples > chloroform extracted water samples. Hexane extract exhibited maximum mutagenic index of 13.0 and induction factor (Mi) 2.48 with TA98. The order of responsiveness based on the mutagenic index and induction factor for the test samples was in the following order: TA98 > TA97a > TA100 > TA102 > TA104. Our findings suggest that TA97a, TA98, TA100, TA102, TA104 were sensitive towards the wastewater extracts and showed considerable mutagenicity.展开更多
Electrocoagulation of pulp and paper industry effluent with SS-304 electrode has been carried out under varying process variable such as pH, current density, time and dose of electrolyte to find out the optimum condit...Electrocoagulation of pulp and paper industry effluent with SS-304 electrode has been carried out under varying process variable such as pH, current density, time and dose of electrolyte to find out the optimum conditions. Maximum reduction efficiency of Chemical Oxygen Demand (COD) 82% and color more than 99% from pulp and paper industry wastewater at the following conditions pH = 7, current density = 24.80 mA/cm2 time = 40 min and dose of electrolytes = 1.0 g/L. Moreover, effects of electrolytes dosage on electricity consumption were observed and found to be that NaCl is better in comparison of Na2SO4 in respect of lower down the electricity consumption. But application of NaCl causes the formation of hazardous compounds as secondary pollutants within treated water. Therefore, Na2SO4 could be a potent replacement of NaCl to enhance the conductivity of paper industry effluent treated by EC process. The treated water has been compared with standard of Central Pollution control board (CPCB) and World Health organization, and found to be suitable for the reuse in irrigation.展开更多
In this study,we have determined the main important physical and chemical properties as well as the heavy metal concentrations of the primary and secondary wastewater treatment sludge from a pulp and board mill comple...In this study,we have determined the main important physical and chemical properties as well as the heavy metal concentrations of the primary and secondary wastewater treatment sludge from a pulp and board mill complex located in Finland in order to evaluate the utilization of these by-products as a soil amendment agent or a fertilizer product.Easily soluble Ca,Mg,K,Na,P and S concentrations in the sludges were extracted by ammonium acetate(CH3COONH4)and easily soluble Cu,Mn and Zn concentrations by CH3COONH4+Na2EDTA.For the determination of total nutrient and total heavy metal concentrations in sludges,they were digested using aqua regia(3 mL HCl+9 mL HNO3).The total heavy concentrations in the primary sludge were lower than the Finnish heavy metal limit values for fertilizer products.In the secondary sludge,all other total heavy metals than the total Cd concentration(4.8 mg/kg;d.w.)were lower than the heavy metal limit values for fertilizer products.Due to the low total heavy metal concentrations,which were lower than the Finnish limit values for fertilizer products,the primary sludge is a potential fertilizer.Although the total Cd concentration(4.8 mg/kg;d.w.)in the secondary sludge exceed the limit value of 1.5 mg/kg(d.w.)for fertilizer products,this residue may be used as a soil improver,a growing media or as a fertilizer product in landfill sites or in other closed industrial areas,because the Finnish limit values for fertilizer products are not applied at these sites.展开更多
文摘Wastewater samples were collected from pulp and paper mill located in Kashipur (India) and were extracted using dichloromethane (DCM), chloroform and hexane solvents (all were HPLC-grade). The extracts were assayed for their mutagenic potential using Ames Salmonella mutagenicity assay. TA98 strain was found to be the most responsive, in terms of induction factor (Mi) and slope (m) of the initial linear dose-response curve as determined by linear regression analysis up to the increasing doses indicating the presence of frame shift mutagens in the test samples. Mutagenicity of different extracts is arranged as follows: dichloromethane extracted water samples > hexane extracted water samples > chloroform extracted water samples. Hexane extract exhibited maximum mutagenic index of 13.0 and induction factor (Mi) 2.48 with TA98. The order of responsiveness based on the mutagenic index and induction factor for the test samples was in the following order: TA98 > TA97a > TA100 > TA102 > TA104. Our findings suggest that TA97a, TA98, TA100, TA102, TA104 were sensitive towards the wastewater extracts and showed considerable mutagenicity.
文摘Electrocoagulation of pulp and paper industry effluent with SS-304 electrode has been carried out under varying process variable such as pH, current density, time and dose of electrolyte to find out the optimum conditions. Maximum reduction efficiency of Chemical Oxygen Demand (COD) 82% and color more than 99% from pulp and paper industry wastewater at the following conditions pH = 7, current density = 24.80 mA/cm2 time = 40 min and dose of electrolytes = 1.0 g/L. Moreover, effects of electrolytes dosage on electricity consumption were observed and found to be that NaCl is better in comparison of Na2SO4 in respect of lower down the electricity consumption. But application of NaCl causes the formation of hazardous compounds as secondary pollutants within treated water. Therefore, Na2SO4 could be a potent replacement of NaCl to enhance the conductivity of paper industry effluent treated by EC process. The treated water has been compared with standard of Central Pollution control board (CPCB) and World Health organization, and found to be suitable for the reuse in irrigation.
文摘In this study,we have determined the main important physical and chemical properties as well as the heavy metal concentrations of the primary and secondary wastewater treatment sludge from a pulp and board mill complex located in Finland in order to evaluate the utilization of these by-products as a soil amendment agent or a fertilizer product.Easily soluble Ca,Mg,K,Na,P and S concentrations in the sludges were extracted by ammonium acetate(CH3COONH4)and easily soluble Cu,Mn and Zn concentrations by CH3COONH4+Na2EDTA.For the determination of total nutrient and total heavy metal concentrations in sludges,they were digested using aqua regia(3 mL HCl+9 mL HNO3).The total heavy concentrations in the primary sludge were lower than the Finnish heavy metal limit values for fertilizer products.In the secondary sludge,all other total heavy metals than the total Cd concentration(4.8 mg/kg;d.w.)were lower than the heavy metal limit values for fertilizer products.Due to the low total heavy metal concentrations,which were lower than the Finnish limit values for fertilizer products,the primary sludge is a potential fertilizer.Although the total Cd concentration(4.8 mg/kg;d.w.)in the secondary sludge exceed the limit value of 1.5 mg/kg(d.w.)for fertilizer products,this residue may be used as a soil improver,a growing media or as a fertilizer product in landfill sites or in other closed industrial areas,because the Finnish limit values for fertilizer products are not applied at these sites.