Coking Wastewater Enhanced Biological Nitrogen Removal

At present, water eutrophication is getting more and more serious in the world, so nitrogen removal becomes one of the most important problems. Oxygen Limited sequencing batch (OL-SBR) is a variant of sequencing batch reactor methodology, it specifically refers to use of the lower oxygen to improve the total nitrogen removal.In this paper, a research was made on the treatment of nitrophenol removal ammonia wastewater from a coke-plant by sequencing batch reactors(SBR).Performance of SBR process treating organic and ammonia was presentd for different operating patterns, aeration time, influent loading, MLSS and pH value at laboratory scale. The experiment was conducted to find the optimum operating pattern and technical parameters .Ah operating mode that incorporated aeration-anoxic portions was utilized. When the operating time was 12h,including aeration time 6h,for the influent with NH3-N of 200~250mg/L,the effluent NH3-N lower than 15mg/L,they met with the Chinese discharge standard of the wastewater. Results from experiment showed that coke-plant wastewater could be treated well by using SBR.If the alkalinity of influent was enough and DO in 0.5-1 .0mg/L,the removal of ammonia and total nitrogen was high. The analysis to balance of nitrogen proved that denitrification could occur in the aerobic condition. The mechanism of the aerobic denitrification was pilot study.The reoval of NH3-N could increase by using zeolite to treat the effuent of SBR.