高温厌氧膜生物反应器处理餐厨废水的启动

以除油后的实际餐厨废水为原料，在高温（50±1）℃条件下利用浸没式纤维膜生物反应器（AnMBR）进行连续厌氧消化试验，以水力停留时间（HRT）20d启动，HRT 15d运行，直到发生膜污染，试验共进行了50d.研究了反应器启动和运行期间的发酵特性和膜过滤性能.研究表明，反应器30d完成了启动，在HRT 15d条件下，甲烷产量达到578L/kgVS_in，COD和挥发性固体（VS）去除率均达到94%以上，膜出水总挥发性脂肪酸（TVFA）浓度为（103±77） mg/L，其中乙酸浓度为（98±28） mg/L.系统pH 8.26，具有良好的稳定性.膜通量设定为9L/（m²·h），运行30d后发生了明显的膜污染，伴随着反应器内挥发性悬浮固体（VSS）浓度由8.1g/L逐渐增加到18/L.在处理高浓度餐厨废水时，AnMBR可以短时间启动且在8.5kgCOD/（m³·d）的高负荷条件下稳定运行，反应器中污泥浓度和溶解性微生物产物的增加导致膜过滤性能下降是导致膜污染的主要因素.

Start-up operation of anaerobic membrane bioreactor treating food wastewater under thermophilic condition

In this study, the actual food wastewater was used as raw material to do experiment with an immersed hollow fiber membrane bioreactor (AnMBR) under thermophilic condition (50±1)℃ for 50days until the membrane fouling occurred. The reactor was started with a hydraulic retention time (HRT) of 20days, and operated at HRT 15days, the system stability and membrane filtration characteristics were studied. The experiment showed that under the above condition, the startup stage can be completed in one month. At HRT 15days, the methane production reached to 578L/kgVS_in, the total chemical oxygen demand (TCOD) and volatile solid (VS) removal rates were both higher than 94%; no volatile fatty acid (VFA) accumulated with a concentration of (103±77) mg/L of the permeate and dominant with acetate ((98±28) mg/L) showed a good stability of the system combined with a pH of 8.26. The membrane flux was set to 9L/(m²·h), membrane occurred parentally after 30days with the volatile suspended solids (VSS) concentration gradually increased from 8.1g/L to 18.0g/L. Research showed that the AnMBR can start in a short time during treating high concentration food wastewater, and run stable under high organic loading rate such as 8.5kgCOD/(m³·d). Long time filtration of the membrane leading to an increasing of VSS and soluble microbial products which may be the main reason causing membrane fouling.