The Research Of The Start-up Characteristics Of Sulfate-Dependent Anammox In HABR System

With the reform and openness deepening,the rapid development of industry and agriculture,the process of urbanization deepening,water pollution has become increasingly serious,organic wastewater containing ammonia and sulfates in the proportion of contaminated water has become increasingly prominent,high concentration of SO42-,NH4+ in the water produced inhibition for microorganisms,so the common biological treatments are difficult for this kind of wastewater.Currently,for this kind of wastewater treatment alone stepwise manner was mainly used,firstly removing SO42-,and then NH4+.However,the traditional biological nitrogen removal or biological sulfur removal technology has some defects,for example high processing costs,the less ideal treatment effect,difficult regulatory mechanisms,causing secondary pollution easily.Sulfate anaerobic ammonia oxidation is a new simultaneous nitrogen and sulfur removal technology developed on the basis of anammox,which has the advantage of obvious degradation effect of SO42-and NH4+ simultaneously,low processing costs.When proposed,it has become a academia concern,which provides a new way to poor biodegradability wastewater technology roadmap.This test is based on the latest research results of nitrate and sulfate removal process sulfate anaerobic ammonia oxidation,synchronize theoretical studies of denitrification sulfur,supply actual project reference of simultaneous nitrogen and sulfur.In this experiment,sulfate-reducing granular sludge was choose as a carrier,started sulfate anaerobic ammonia oxidation reaction quickly in HABR reactor and research the reaction mechanism;explore the effect of anaerobic sulfate ammonia oxidation by setting different concentrations of COD.Testing results are as follows:(1)HABR reactor was stared by using low load operation continuously,after 65 days,at the conditions of 7<PH<8.5 and temperature 32 ± 1 ℃,the sulfate reduction was started successfully in HABR,enrichment cultivate mature sulfate-reducing granular sludge,maximum removal rate of SO42-was 85.5%,COD was 68.8%,The maximum amount of elemental sulfur accumulation was 75.8mg/L.When SO42-loading rate was in the range of 0.9-1.2kgSO42-/(m3·d)and HRT was 6-8h,the removal rates of SO42-and COD were maintained above 80%and 60%,elemental sulfur accumulation remained above 55mg/L.When improving the loading rate of SO42-、COD and S0 continuoUsly,the removal efficiency decreased.The optimum conditions of sulfate reduction in HABR were SO42-toading rate was in the range of 0.9-1.2kgSO42-/(m3·d)and HRT was 6～8h.The reactor enriched sulfate-reducing granular sludge successfully,which was dark black and sludge particle size 2～3mm accounted for 70%,lay the basis for subsequent starting sulfate anaerobic ammonia oxidation reactor quickly.(2)The method of using the low loading operation,through 150 days continuous stream running in HABR,sulfate anaerobic ammonia oxidation was started on the basis of previous stage sulfate-reducing particles,the removal rates of NH4+-N and SO42-reached 52.5%and 53.8%,the reactor starting-up time has been shortened,but not obvious.Indices,for example N44+-N,SO42-,COD,NO2--N,NO3--N and S2-,were detected in each compartment of HABR,and analyzes bacterial population evolution in each compartment.The results showed,sulfate anaerobic ammonia oxidation reaction compartment in HABR was conducted through compartment and procedure step by step.NH4+-V and SO42-oxidation-reduction reaction making NH4+-N and SO42-converse into NO2--N and S2-was mainly conducted in compartment one;anaerobic ammonia oxidation was mainly conducted,making the remaining N14+-N and intermediate NO2--N converse into N2 in compartment three;in compartment four mainly making S2-and NO2--N converse into N2 and S0.There was still a part of sulfate-reducing bacteria in compartment one,conducting sulfate reduction,nitrification and a little denitrificatioa The bacterial population composition is conmplex in compartment one,along the horizontal direction of the reactor the bacterial population reduced gradually,showing a single trend.In the terms of the reaction system,there was not merely sulfate anaerobic ammonia oxidation process,but sulfate reduction,nitrification,denitrification and other mixed results.Every bacterial population exhibited the competitive relationship.(3)The effect of organic matter concentration to sulfate anaerobic ammonia oxidation reactor that was operated stably was studied.On the basis of sulfate anaerobic ammonia oxidation reactor stable operation,the effect of organic matter to the reactor by setting COD concentration gradient was investigated,the results showed that:when COD concentration was 150mg/L,it can produce promotion to the anaerobic ammonium sulfate oxidation reactor,the maximum removal rate of NH4+-N was 60.6%,SO42-was 59.1%.Compared with the rate during sulfate anaerobic ammonia oxidation reactor,the removal rate of NH4+-N and SO42-improve about 10%.When COD concentration was less than 150mg/L,it can produce little effect to the anaerobic ammonium sulfate oxidation reactor;when COD concentration was more than 150mg/L,it can produce inhibition to the anaerobic ammonium sulfate oxidation reactor,COD optimum concentration range was 120-150mg/L.Sulfate anaerobic ammonia oxidation reaction should be conducted in lower COD concentration environment,lower concentrations of COD make sulfate anammox bacteria associated with other bacteria showed synergistic symbiotic relationship,and the appropriate COD concentration can produce promotion to the reaction process.