Treatment of Wastewater with High Concentration of Ammonia Nitrogen through ASBR Combining with Pulsed SBR
Wang Shuying,Zhu Rulong,Wang Kai and Miao Lei
DOI:10.3969/j.issn.1674-4764.2013.01.020
Received ,Revised , Accepted , Available online July 01, 2015
Volume ,2013,Pages 121-127
- Abstract
In order to analyze the nitrogen removal performance of anaerobic-aerobic process treating landfill leachate, a system combining ASBR with pulsed SBR was applied to treat real landfill leachate with high concentration of ammonia nitrogen. The HRT of ASBR was 2 d; middle water tank regulated the COD/NH +4-N (3～5) and NH +4-N concentration of pulsed SBRs influent; the cycle of pulsed SBR consisted of four anoxic stages and three oxic stages in which three equal feeds model was applied. In the fourth anoxic stage (An4), internal carbon source was used to implement denitrification without any extra carbon source addition. The results indicate that efficient nitrogen removal performance of this system was achieved in the series running period (157 d). Influent chemical oxygen demand (COD) concentration of ASBR was from 7 338 mg·L -1 to 1 0445 mg·L -1 of which above 83% was removed; pulsed SBRs influent NH +4-N concentration could be divided into four phases in which improving from 296.1±14.5 mg·L -1 to 912.0±41.7 mg·L -1, and the effluent total nitrogen (TN) concentration of pulsed SBR was below 40 mg·L -1 all the time, which means TN removal rate reached over 90%. To sum up, the COD and TN removal rate of the combined system were above 87% and 97%, respectively. Endogenous denitrification rate(DNR) of An4 changed from the fast one to the slow one, and the mean value of theoretical denitrification rate (TDNRm) of pulsed SBRs An4 could reach 1.531 mg N·h -1·gMLVSS -1. Advanced nitrogen removal of the system was realized without extra carbon source addition and physicochemical pre-treatment.