中温UASB反应器处理餐厨垃圾废水中试研究

Pilot-scale Study on Treatment of Food Wastewater by Mesophilic UASB Reactor

利用一个有效容积为28 m^3的UASB反应器在(35±2)℃条件下进行了餐厨垃圾废水半连续式中温厌氧消化试验。通过增加进料量提高进水容积负荷,使水力停留时间(HRT)由50 d逐步降低至10 d,研究了HRT和进水容积负荷对处理效果的影响。结果表明,在HRT=14 d、进水容积负荷为4.96 kg COD/(m^3·d)时达到最佳运行工况,其容积产气量稳定在2.68 m^3/(m^3·d)左右,产气率达0.66 m^3/kg COD,COD容积去除负荷为4.21 kg COD/(m^3·d)。当HRT为12~35 d时,对COD的去除率稳定在82.59%~87.78%之间,出水VFA/碱度值维持在0.1~0.38之间,表明反应器具有足够的抗酸化缓冲能力,在该HRT范围内均可稳定运行。

Mesophilic anaerobic digestion of food wastewater was studied using a UASB reactor with effective volume of 28 m3 under mesophilic condition of （35±2）℃. The influence of hydraulic re- tention time （HRT） and the organic loading rates （OLR） of the reactor on the treatment efficiency were investigated by increasing OLR and decreasing HRT from 50 d to 10 d. The results indicated that the sys- tem performed best at the HRT of 14 d with OLR of 4.96 kgCOD/（m3 ·d）. Under the optimum operat- ing conditions, volumetric gas production rate maintained at about 2.68 m3/（m3 · d） , and the maximum gas production rate reached 0.66 m3/kgCOD with OLR removal rate of 4.21 kgCOD/（m3 · d）. When HRT was 12 d to 35 d, the removal rate of COD was 82.59% to 87.78%, and VFA/alkalinity ratio of the UASB effluent was maintained at 0.1 to 0.38, implying that the reactor could be operated stably in the HRT range with a high buffering capacity against acidification