State Key Laboratory of Heavy Oil Processing, China University of Petroleum-Beijing, Beijing 102249, China.
School of Petroleum Engineering, Yangtze University, Wuhan 430100, China.
Int J Environ Res Public Health. 2021 Jun 23;18(13):6742. doi: 10.3390/ijerph18136742.
A pilot-scale airlift bioreactor (ALBR) system was built and operated continuously for refinery excess sludge (RES) reduction. Combined ALBR and function-enhanced microbes (composed of photosynthetic bacteria and yeast) were integrated into the system. The pilot-scale ALBR was operated for 62 days, and the start-up time was 7 d. Continuous operation showed that the sludge reduction efficiency was more than 56.22%, and the water quality of the effluent was satisfactory. This study focused on investigating the effects of hydraulic retention time (HRT) on the stability of the system and the effect of sludge reduction. Under different HRT conditions of 40, 26.7, 20, and 16 h, the sludge reduction rates reached 56.22%, 73.24%, 74.09%, and 69.64%, respectively. The removal rates of chemical oxygen demand () and total nitrogen (TN) decreased with decreasing HRT, whereas the removal rate of NH-N increased. The removal rate of total phosphorus (TP) was approximately 30%. Results indicate that the ALBR and function-enhanced microbe system can reduce sludge and treat sewage simultaneously, and the effluent is up to the national emission standard. Addition of function-enhanced microbes can promote the degradation of petroleum hydrocarbon substances in the sludge, especially alkanes with low carbon numbers. This study suggests that the optimal HRT for the system is 16 h. The total operation cost of the ALBR combined with the function-enhanced microbe system can be reduced by 50% compared with the cost of direct treatment of the RES system.
一个中试规模气升式生物反应器（ALBR）系统被构建并连续运行，用于炼油厂剩余污泥（RES）的减少。将气升式生物反应器和功能增强微生物（由光合细菌和酵母组成）结合到系统中。中试规模的气升式生物反应器运行了 62 天，启动时间为 7 天。连续运行表明，污泥减少效率超过 56.22%，出水水质令人满意。本研究重点研究水力停留时间（HRT）对系统稳定性和污泥减少的影响。在不同的 HRT 条件下，分别为 40、26.7、20 和 16 h，污泥减少率分别达到 56.22%、73.24%、74.09%和 69.64%。化学需氧量（COD）和总氮（TN）的去除率随 HRT 的降低而降低，而 NH-N 的去除率增加。总磷（TP）的去除率约为 30%。结果表明，气升式生物反应器和功能增强微生物系统可以同时减少污泥和处理污水，出水达到国家排放标准。添加功能增强微生物可以促进污泥中石油烃物质的降解，特别是低碳数的烷烃。本研究表明，系统的最佳 HRT 为 16 h。与 RES 系统的直接处理成本相比，气升式生物反应器与功能增强微生物系统的总运行成本可降低 50%。
