Study On Iron Chipping Inner-electrolysis Process For Pretreating Ramie Wastewater

In this article, the working principle and action mechanism of Fe chipping inner-electrolysis process are studied. It is used to pretreat ramie wastewater that has high COD concentration, high color and some toxicants to microorganics.This research has three sections:1) Some technology control-factors are studied through orthogonal experiment to study their impact on treating effect. PH value, retention time, aeration, and temperature are chosen as control factors. COD, BOD and color are indicating indexes for estimating treating effect. The result shows that effecting order is PH value, aeration, and temperature, retention time. The lower the PH value is, the longer the retention time is, the bigger the aeration is, and the higher the temperature is, the better the efficiency is. Generally, the removal rate of colors and COD are respectively 30% and 20%. The biogradability of effluent is improved and the toxicity is reduced. It achieves the goal of pretreating. The single factor experiments to PH value and retention time are conducted respectively. The results show that when PH value is 2～4,the treating effiency is the best; when retention time is exceeding 40min, the efficiency goes to stabilization.2) The influences of metal oxides are studied through adding them to the Fe-C carrier. Now, salt and metals are used as additives, but they both have limits. In this article Al2O3, MnO2, CuO are chosen as additives. At the same conditions, when adding different metal oxides with different proportions, the removal rate of COD is improved to 38.3～48.6% from 32.5%.The removal rate of color is improved to 47～60% from 42%. It can be concluded that the metal oxides contribute to the reaction.3) The inner-electrolysis process and iron coagulation process are both used to pretreat ramie wastewater. The results show that the efficiency of inner-electrolysis process is better than the one of iron coagulation process. The removal rates of COD and color of inner-electrolysis process are 32.5% and 42%, while the ones of iron coagulation process are 26.3% and 30%.Via this experiment research, the elemental theory and technology foundation can be offered for project design and running. In the real project, the factors should be modified according to the reality to get the best result...