生物法降解含油污泥反应器流场及工作参数研究

为提高生物反应器法处理含油污泥的降解效率,对生物反应器内铜绿假单胞菌NY3降解含油污泥的工艺过程进行研究.建立了生物反应器内气-液-固三相流场动力学模型和群体平衡模型(PBM),结合FLUENT软件对反应器内气泡直径分布和搅拌转速进行仿真.研究发现,直径在6mm以下的气泡占比为85%,能有效增加反应体系溶解氧浓度,并模拟出反应器最佳离底悬浮转速为150r/min.利用氧守恒原理建立了曝气速率随时间的变化关系模型,并通过设计实验确定最佳接菌量为15.23%,温度为32.56℃,指导最终降解过程的工艺参数选择.通过设定最佳工作参数值,用多功能生物反应器对6kg含油污泥进行降解实验,反应9d后石油烃降解率高达86.20%,含油率为1.46%.研究结果表明,生物反应器法降解含油污泥周期短、效率高,为处理含油污泥提供了一种有效可靠的新途径.

Study on flow field and working parameters of bioreactor for oily sludge degradation

In order to improve the degradation efficiency of oily sludge by bioreactor, the degradation process of oily sludge by pseudomonas aeruginosa NY3 in bioreactor were studied. The gas-liquid-solid three-phase flow field dynamics model and population balance model (PBM) in the bioreactor were established, and the bubble diameter distribution and stirring speed were simulated by FLUENT software. It was studied that the bubbles with a diameter of less than 6mm account for 85%, which can effectively increase the concentration of dissolved oxygen in the reaction system,and the optimal off-bottom suspension speed of the reactor was 150r/min. Secondly, the relationship model of aeration rate with time was established by using the principle of oxygen conservation, and the optimal bacterial uptake was determined to be 15.23% and the temperature was 32.56℃ through design experiments, which guided the selection of technological parameters in the final degradation process. Finally, the optimal working parameters were set, and 6kg oily sludge was degraded by multi-functional bioreactor. After 9 days of reaction, the degradation rate of petroleum hydrocarbon was up to 86.20%, and the oil content was 1.46%. The bioreactor degradation of oily sludge has the advantages of short cycle and high efficiency, and provides an effective and reliable new way for the treatment of oily sludge.