TREATMENT METHOD FOR ORGANIC WASTEWATER, TREATMENT APPARATUS FOR ORGANIC WASTEWATER, AND POLYMER FLOCCULANT

To provide a method for treating organic wastewater, especially organic wastewater that is difficult to dewater, a treatment apparatus for organic wastewater, and a polymer flocculant capable of performing stable dewatering treatment.SOLUTION: For organic wastewater that is difficult to dewater and contains at least some of human waste and septic tank sludge, the following conditions are required for the polymer flocculant: (1) 0.5% salt viscosity of 10 to 90 mPa-s, (2) the number of moles of cationic monomer and anionic monomer contained in all monomers constituting the copolymer contained in the polymer flocculant. The method for treating organic wastewater in which a polymer flocculant is added to the polymer flocculant satisfying a composition ratio of 25 to 90 mol% for the cationic monomer and 10 to 75 mol% for the total of the anionic and nonionic monomers. The concentrated sludge is then dewatered followed by concentration treatment and dehydration treatment.SELECTED DRAWING: Figure 1 【課題】有機性廃水、特に、難脱水性の有機性廃水に対しても安定して脱水処理を行うことが可能な有機性廃水の処理方法、有機性廃水の処理装置及び高分子凝集剤を提供する。【解決手段】屎尿と浄化槽汚泥の少なくとも何れかを含む難脱水性の有機性廃水に対し、高分子凝集剤として下記条件：（１）０．５％塩粘度が１０～９０ｍＰａ・ｓ、（２）高分子凝集剤に含まれる共重合体を構成する全単量体に含まれるカチオン性単量体のモル数と、アニオン性単量体のモル数と、ノニオン性単量体のモル数とのうち、カチオン性単量体の構成比率が２５～９０ｍｏｌ％であり、且つアニオン性単量体及びノニオン性単量体の合計の構成比率が１０～７５ｍｏｌ％、を満足する高分子凝集剤を添加して凝集処理した後に濃縮処理し、濃縮汚泥を脱水処理する有機性廃水の処理方法である。【選択図】図１