Study Of The Optimum Operation In Piggery Wastewater Treatment By Anammox

Piggery wastewater,which is characterized by high concentration of COD,ammonium and suspend substance,is mostly emitted directly without appropriate recycle and treatment,which brought about a serious pollution to the environment.To be directed against the characteristic of piggery wastewater,anaerobic digestion and aerobic digestion process combined with physical-chemical resource preservation methods are adapted.How to discharge piggery wastewater with the ammonium concentration meeting standard by economical and effective method? This is the most urgent problem in piggery wastewater treatment.Anammox has advantages of no need of organic carbon addition,low oxygen consumption and energy consumption.As a new biological nitrogen removal technology, Anammox process has been paid more and more attention by researchers all over the world. Plenty of investigations have been carried out to the mechanism,physiological and biochemical characteristic of bacteria about Anammox.Most of researches focused on synthetic wastewater, there is rare report about its application in piggery wastewater.A Sequencing Batch Reactor was used in this investigation to treat piggery wastewater,The culture of anaerobic oxidation biomass seeded with anaerobic digest,in the SBR reactor,The start-up of reactor and working conditions were studied.Several conclusions were summarized as follows:(1)It took more than four months that ANAMMOX reactor was started up successfully under the 100mg/L concentration of ammonia nitrogen(NH₄⁺-N)and nitrite nitrogen(NO₂^--N), which was departed into initial phase of startup,transition period and steadily operative period.At the end of the reactor startup,the removal rate of ammonia and nitrite achieved 91.7%,92.4%respectively;The volume loads of ammonia and nitrite were respectively 36.9mg/(L·d),37.6mg/(L·d).(2)In the process of the wastewater's concentration was heightened from 100mg/L to 450mg/L.The removal rate of ammonia and nitrite dropped,because a little oxygen entered the reactor,which inhibited the culture of anaerobic oxidation biomass.The removal rate of ammonia and nitrite was enhanced again by reinstating experimentation's conditions.This manifested the culture of anaerobic oxidation biomass can regain activity.(3)Under the low concentration of ammonia,the appropriate condition of reactive control for Anammox bioreactor were as follows:the appropriate value of pH was between 7.5 and 8.0;the appropriate value of temperature was between 32℃and 34℃.the optimal HRT value was 1.2d.,Through the influence study of single factor like pH,temperature,HRT matter on the ANAMMOX reaction. (4)Based on the single factor experiment,the full-scale test about influence factors as pH, temperature and HRT were done.The results of full-scale test indicated that:the primary and secondary sequence of the factors effecting the ANAMMOX removal rate of ammonia and nitrite were pH,temperature,HRT and the optimal value of pH,temperature and HRT were respectively 7.5,3 3℃,1.2d。...