The Research And Application Of Pulp & Paper Wastewater Advanced Treatment

The state environmental protection agency authorize The Discharge standard of Water Pollutants for Pulp and Paper Industry (GB3544 -2008) On June 25, 2008. The new standard is more strictly than the original one. Also increased Nitrogen, Phosphorus , AOX and Chroma indicators etc. And to the old Waste paper pulp and Papermaking Enterprises, the new Discharge standard will carry out from 2009, May 1. One the biggest change is COD_Cr,the standard will from the original 250mg/L down to 120mg/L. Only with normal level 2 treatment process, it is difficult to reach new emissions requirements. Therefore, in search of an effective and feasible deep treatment for many enterprises of papermaking industry, it is urgent.Combining with the Guangzhou paper co.,LTD's sewage treatment system technology reconstruction project, through various depth of pulping and papermaking wastewater treatment process for feasibility and efficiency analysis, and test, project construction, and productive operation analysis, obtained the following conclusions:1. The Pulp & Paper Wastewater after secondary biochemical treatment, biochemical sex is poorer, can be difficult to continue using biological treatment technology for further deep treatment, can consider the chemical coagulation, advanced oxidation process, or combinations of process.2. Choose appropriate flocculants and dosing amount reaches a certain chroma, coagulation chemical method can further remove stubborn biodegradable COD_Cr and chroma of The Pulp & Paper Wastewater. For the experiment USES The Pulp & Paper Wastewater treatment after biochemical treatment (pH 7.13,TCOD_Cr 176.5mg/L,SCOD_Cr 157.4 mg/L,SS 38.0 mg/L,BOD5 9.5 mg/L,chroma 50 times), SCOD_Cr removal can reach more than 45%, chroma removal rate can amount to 84 percent or more. Tons of water treatment costs can be controlled in 1.0 RMB.3. Use the shallow air-floatation for pulp &paper wastewater biochemical treatment after in-depth processing, Processing cost (including electricity) about 0.8 yuan/m3. Determined.the decolored rate can reach 85%, COD_Cr removal rate as high as 50.0%. In the case of biochemical system effluent COD_Cr < 200mg/L, Can be a constant flow in 100mg/L below, and Meet the latest emission requirements. Relative to other deep treatment, with lower cost, decoloring, pollutant removal efficiency, stable operation, simple operation etc. In the current environmental technology level condition, can say it is a more appropriate depth of pulping and papermaking wastewater treatment process.