Study On The Pilot Test For The Advanced Treatment Of Bleaching Effluent Of Paper-Making

Since our very serious water pollution caused by industrial emissions, and paper making waste water account for a substantial proportion. So paper industry waste water treatment is not only the focus of attention in the paper industry, and even in the whole society, but also, it is the key to the survival and development of these enterprises. Bleaching effluent of the paper industry is one of the main sources of pollution. Most paper mills facing the wastewater treatment and reuse of wastewater.According to the《Shan Dong province along the line of south-north water transfer water pollutants discharge standard systems》, the pilot test from the point of view of engineering design, made a feasible pilot program of the wastewater treatment and reuse technology. The latest membrane technology process was used to treat waste water in the experiment. The main concern is COD and color removal efficiency of Bleaching effluent. After nearly one year of the pilot, it is revealed that the technology can meet the requirements of the《standard》. After the advanced treatment of the wastewater ,the treated water can be used to each section of the paper mills completely.According to this study, the following conclusions were drawn :1.The decolorization effect of the decolor coagulant is obvious, but it has the low removal efficiency of COD. Therefore decoloration coagulant selection may not be applicable to the sewage treatment plant to the existing technology. However, because of its small dosage of the coagulant, by using the reverse osmosis means, the salinity treated water is not increased. So it has certain advantages undoubtedly.2.The trial of improved technology, with the means of UF(ultrafiltration), showed that it can intercept the macromolecule after coagulation and sedimentation. Despite the high COD content of the ultrafiltrate, it can used to the influent of RO(reverse osmosis). However, the UF freshwater's SDI is lower than 5, so the life of the RO membrane will not be influential.3.For the delay aeration sewage, although its biodegradation is poor, the MBR still have a certain effect for the COD remove, and the effect has become more pronounced, especially after a special biological domesticated means, due to its high sludge concentration. 4.After the combination of advanced process, RO process can be operated normally at a high COD influent. The COD and Chroma of the final drainage mixed with the fresh water of RO,UF and MBR remained at 100 mg/l and 50 below, respectively.The successful pilot-testing can provide better guidance and reference for future bleaching effluent treatment projects. Meanwhile, the pilot-testing discussed the issues arising in the course of the appliction of membrane separation technology, and put forward the possible solutions.