Coking Wastewater Denitrification Process And Mechanism,

This paper used anoxic and improving SBR combined technology to study Guangzhou coke-plant wastewater, which is famous for its high concentration of COD and ammonia.First, we use anaerobe to change some hard to degrade organic compounds to small molecular and easy to decomposed organism, then, for SBR process can be manipulated vividly, we added antinitrification after nitrification to increase ammonia removal. Anoxic-SBR combined process can united oxic reaction and anoxic reaction, using the advantage of different microbes, which has a good applying prospect to remove high concentration COD and ammonia.We determinated optimum process parameter through experiments and analysed denitrification mechanism and effecting factors. This paper aimed at developing a reasonable process to dispose coke-plant wastewater, offering some theoretical and practical referencing data for changing and extending such process for wastewater like coke-plant wastewater. Experimental results show:Anoxic pretreatment can increase biochemical quality, time to gain the highest biochemical quality is 4 hours; the results of pretreatment are apparent, compare single SBR process, removal of COD and ammonia increased 13.2% and 10.7% respectively.Best processing parameter of post-SBR is: aeration(8h) +mixing(3h) +aeration (4h) +settling (1.5h) +drawing (0.5h); Different added carbon have effect on results, methanol proved to be the best among the experimental reagents.Nitrifying and dinitrigying in one SBR reactor increased the difficulty of taming. Separating the microbes of taming beginning and end showed that, sorts of microbes decreased; we screened six single and one associated microbes in all which had high degrading ability;The changing regular of during the remove of COD and ammonia in SI3R reactor connected closely with all reactions. That is: monitoring pH at all time can determinating the time of aeration and mixing accurately, so large pH motion can be avoided; COD and ammonia concentrat ion of influent have an effect on pH, it changes with their concentrations.