A study on the effect of ozonation and coagulation- flocculation processes on kraft pulp mill effluents has been carried out. The objectives were to determine (1)best chemical combination for coagulation-flocculation, (2)optimum pH for ozonation and to evaluate (3)suitability of ozonation as pre and post treatment of coagulation-flocculation. Removal efficiencies of color, turbidity and phenolic compounds were investigated under different conditions. Results indicated that initial acidic pH in the effluent is more favorable for ozonation at the experimented O₃ flow rate. Use of 0.1g/L AlCl₃.2H₂O with 0.05g/L polyacrylamide gives the maximum reductions of color, turbidity and phenolic compounds in the effluent. Coagulation-flocculation followed by ozonation is a better system for the treatment of kraft pulp mill effluent. This system can reduce all the three parameters by about 90%.

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   This paper describes the authors. attempt to measure effects of environmental regulations imposed on industrial solid waste generation. Productivity was measured using the Luenberger Productivity Index based on Data Envelopment Analysis. The sources of productivity change were examined by decomposing the observed index into efficiency change and technical change components. Results show that Japanese manufacturing industries have entered a stagnant phase and actually showed no high productivity growth during 1990-2006. Furthermore, positive changes in surviving industries mainly result from technological innovation, not from improved efficiency.

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   Kitchen waste water emerging from Tirumala hills, a world famous piligrim centre was used as a source of nutrients for cultivation of Nostoc muscorum. A complete randomized design (CRD) was created for the experiment which was performed on BG-11 medium, 100% kitchen waste water (100% KW) and 75% kitchen waste water (75% KW). The physicochemical properties of kitchen waste water and the yield of biomass were determined from the cultures harvested every three days for a period of 15 days. After cultivation the kitchen waste water met the standards of safe discharge in India. The organisms could able to remove maximum of 98% of contaminants during its growth in waste water. The highest production of biomass was achieved in BG-11 medium followed by 100% KW and 75% KW.

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   Recent years have witnessed increased attention being given to the evaluation and selection of alternative waste treatment strategies from the view of reduction of greenhouse gas (GHG) emissions. However, a long period of waste records is necessary for getting acceptably accurate results, especially in calculating GHG emission from disposal site. Therefore, in this paper, applying the systematic approach we have developed in the previous work, the back-casting and ex-post forecasting of the waste quantity by composition in the past is conducted. Then, current GHG emissions in five Chinese metropolitan cities are investigated and analyzed; thereafter, a scenario analysis is carried out in Shanghai based on the forecasts of waste generation and the corresponding waste category in 2015. Methane (CH₄), carbon dioxide (CO₂) and nitrous oxide (N₂O) are mainly taken into account in GHG emission due to significant amount emitted from waste treatment. The results confirm that the per capita CO₂ emission factor (kg CO₂-eq/kg waste-treated) in Shanghai, Guangzhou, Hangzhou, Wuhan and Chengdu in 2007 is 0.48, 0.59, 0.57, 0.41 and 0.48 respectively, thereby demonstrating that economic growth is the main driving force of GHG emissions currently observed in Chinese cities. Further, through the scenario analysis, composting and integrated waste management are considered as effective attempts at reducing GHG emissions in Shanghai.

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