Experimental Study On The Removal Of Nitrogen And Phosphorus In Filtration Intermittent Biofilm Reactor (FIBR)

According to the water quality characteristics of Guangdong province, based on theprevious studies, this study developed a filtration intermittent biofilm reactor (FIBR), withthe introduction of suspension carrier in CIBR reactor, then through water filter. In theexpe riment stage without setting filters, this study researched the way of enrichmentdenitrifying bacteria and denitrifying bacteria in the reactor to improve the effect ofnitrogen removal; looked for the operating mode satisfied with the requirements of thewater quality in the intermittent aeration test; Explored the regulation of the effect ofoperation system and hydraulic retention time changes in the best HRT test; InvestigatedDO, ORP, pH change in rule with the effect of nitrogen and phosphorus removal in theFIBR on-line control tests. The research results are as follows:(1) The intermittent aeration test found that the effect of operation system influencedby the aeration time, mixing time, static sink, aeration ratio etc. With dosing film carrier,MLSS increased obviously and the effect of nitrogen and phosphorus removalsignificantly enhanced. In the ope ration cycle of4hours, the model of2hours aeration,1hour stirring and1hour settling is significantly better than the other mod es, and theeffluent satisfied with the first B-grade discharge standard specified in GB18918--2002. Inthe operation cycle of6hours, the model of3hours aeration,2hour stirring and1hoursettling is significantly be tter than the other modes, and the effluent satisfied with the firstA-grade discharge standard specified in GB18918--2002.(2) The best HRT test found that the research results are similar with4hours or6hours ope ration cycle. With the shortening of HRT, the removal rate of COD, NH3-Ngradually reduced, the removal rate of TN changed a little, the removal rate of TPincreased first then decreased in the end. To ensure the effluent stably satisfied thedrainage standard, HRT maintaining about8hours was suggested.(3) The online control test found that the changing laws of DO, ORP, pH changecurves are similar with the changing laws of the classic curves of SBR, but the appearedtime and form of feature points are different. Effective online control cannot realizerelying on th change rule of a single parameter. Only if the three parameters of DO, ORP, pH changes rules were relied on can we effectively judge all reaction phases of nitrogenand phosphorus removal. The regulation of aeration and agitation proc ess can beoptimized with the characteristics of DO, ORP, pH changes rules as online control strategycriterion of the FIBR process.