Advanced Treatment of Washing and Bleaching Effluent of Wheat Straw Pulp with Using Iron Chips Micro-Electrolysis-Coagulate Process

Iron chips micro-electrolysis-coagulation process for advanced treatment of washing and bleaching effluent of wheat straw pulp was studied. The optimal condition was determined as follows: adjust initial pH value of the effluent to 5.2, then add iron chips(the volume ratio of wastewater to iron chips was 3.0) to carry out micro-electrolysis reaction. After 20 min reaction in aeration, the pH value was adjusted to about 9.3 and start to coagulate and sedimentate. In the optimal condition, the removal rate of COD Cr and chromaticity was up to 68.4% and 98.7% respectively, the effluent was transparent. Meanwhile, ultraviolet atomic absorption spectrum graph showed that, the range and intensity of absorption decreased greatly, structures such as conjugated double bonds and six carbon rings which are the characteristic of benzene series were also decreased. Comprehensive effect of micro-electrolysis on removing pollutants was tested.