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The effluent from Bamboo CTMP pulping process has been characterized, and various treatment-processing stages and their efficiencies were investigated. With comparison to wood CTMP effluent, This type effluent could be concluded with followed aspects such as 1) higher COD Load, 7320 mg/l; 2) higher nitrogen (ammonia ) contents, higher than 500 mg/l Combinations of anaerobic and aerobic bio-reactors were applied to investigate the removing efficiencies of pollutants. This system could be organized with four stages: flocculation stage, anaerobic stage, aerobic stage and post-flocculation stage. In the first stage, using of PSAFCS No.2 with a dosage of 2000 mg/l, removals of COD, BOD and SS can be increased up to about 49.4%, 46.4% and 71.1%, respectively; In anaerobic stage, those of COD, BOD, SS up to about 85.4%, 86.8% and 60.1%; In the aeration treatment stage, those of COD, BOD, SS about 68.4, 84.5, 52.5%, respectively. The discharged water from this system could meet the regulation of local effluent discharging standard, COD, BOD, SS and color have been significantly brought down to 172 mg/l, 27 mg/l, 72 mg/l and 150 times, respectively. The investment of project for treating wastewater is about 1400 yuan RMB per stere; the run cost is about 1.0-1.2 yuan RMB per stere. This multi-bio-stages sequence may become a suitable measure for the treatment of high consistency effluent from Bamboo CTMP process economically and to meet the local regulation for pulping effluent discharging in Sichuan province.
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