Jeison D, van Lier J B
Sub-department of Environmental Technology, Wageningen University, P.O. Box 8129, 6700EV Wageningen, The Netherlands.
Water Res. 2007 Sep;41(17):3868-79. doi: 10.1016/j.watres.2007.06.013. Epub 2007 Jun 12.
The long-term operation of two thermophilic anaerobic submerged membrane bioreactors (AnSMBRs) was studied using acidified and partially acidified synthetic wastewaters. In both reactors, cake formation was identified as the key factor governing critical flux. Even though cake formation was observed to be mostly reversible, particle deposition proceeds fast once the critical flux is exceeded. Very little irreversible fouling was observed during long-term operation, irrespective of the substrate. Critical flux values at the end of the reactors operation were 7 and 3L/m(2)h for the AnSMBRs fed with acidified and partially acidified wastewaters, respectively, at a gas superficial velocity of 70m/h. Small particle size was identified as the responsible parameter for the low observed critical flux values. The degree of wastewater acidification significantly affected the physical properties of the sludge, determining the attainable flux. Based on the fluxes observed in this research, the membrane costs would be in the range of 0.5euro/m(3) of treated wastewater. Gas sparging was ineffective in increasing the critical flux values. However, preliminary tests showed that cross-flow operation may be a feasible alternative to reduce particle deposition.
采用酸化和部分酸化的合成废水研究了两个嗜热厌氧浸没式膜生物反应器（AnSMBRs）的长期运行情况。在两个反应器中，滤饼形成被确定为控制临界通量的关键因素。尽管观察到滤饼形成大多是可逆的，但一旦超过临界通量，颗粒沉积就会迅速进行。在长期运行过程中，无论底物如何，几乎未观察到不可逆污染。在气体表观流速为70m/h的情况下，以酸化和部分酸化废水为进水的AnSMBRs在运行结束时的临界通量值分别为7和3L/m²·h。小粒径被确定为观察到的临界通量值较低的相关参数。废水酸化程度显著影响污泥的物理性质，从而决定可达到的通量。基于本研究中观察到的通量，膜成本将在每立方米处理后废水0.5欧元的范围内。气体曝气在提高临界通量值方面无效。然而，初步试验表明，错流运行可能是减少颗粒沉积的一种可行替代方法。
