Research On Refinery Wastewater Processing By MBBR And CAOT Technology

MBBR and CAOT technology was used to process refinery wastewater pollutants. This paper discussed the influence of MBBR and CAOT on COD and ammonia-nitrogen removal, and the system's shock upholding capacity, opening up new paths of using MBBR and CAOT processing refinery wastewater.Engineering application showes that the average removal rate of MBBR to COD was 18.1% and maximum 38.0% when the COD average concentration of influent reached 108mg/L; and this number was 12.9% and maximum 28.0%, when the COD average concentration of influent reached 93.2mg/L. MBBR has strong ability in removing ammonia-nitrogen from wastewater, the ammonia-nitrogen concentration from MBBR effluent was below detection limitation when the influent concentration of ammonia-nitrogen was lower less than 20mg/L. Engineering application also proved that MBBR can quickly resume operation after withstanding the impact of high concentration COD for two consecutive days; and it took one week for MBBR to recover to its normal state after being impacted by high concentration COD wastewater; the nitrification and denitrification systems took longer time to recover when destroyed by the strong impact, two months for natural recovery, and only two weeks for artificial maintenance.The processing efficiency of CAOT to high concentration COD in wastewater was superior to processing low concentration COD. The average removal rate of CAOT to COD can reach 43.9% when the average influent COD concentration was 173mg/L, and maximum 60.6%; and this number was only 24.8% when the average influent COD concentration was 88.0mg/L.This paper concluded that using the combination of MBBR and CAOT can lay a practical foundation for further processing refinery wastewater.