乙酸丙酸比例对富集聚磷菌生物除磷系统影响研究

通过丙酸/乙酸(以C计)比例为0.1、0.5、1、2、10的合成废水,在SBR反应器(1#～5#)中长期驯化聚磷菌(PAO)富集的污泥,研究了丙酸/乙酸比例对增强生物除磷系统(EBPR)中短链脂肪酸(SCFA)降解、溶解性正磷(SOP)的释放/吸收及其去除率的影响.结果表明,PAO对SCFA的利用符合一级动力学过程,PAO对丙酸的利用速率较乙酸快,因此,增加丙酸/乙酸比例有助于EBPR系统的稳定性.随丙酸/乙酸比例增加,SOP的释放与吸收量减少,SOP的代谢速率降低,但SOP的去除率明显增加.因此,增加丙酸/乙酸比例有助于提高EBPR系统除磷效率.

Effect of different ratios of propionic to acetic acid on phosphorus removal by an enriched culture of phosphorus accumulating organisms

The lab-scale anaerobic-aerobic sequencing batch reactors were operated with PAO activated sludge long-term cultivated respectively with an average propionic to acetic acid carbon molar ration of 0.1, 0.5, 1, 2, 10(reactor 1~#~5~#). The influences of propionic/acetic acid ratio on short-chain fatty acids (SCFA) metabolism, and phosphorus release, uptake and removal during Enhanced Biological Phosphorus Removal (EBPR) were investigated. The results showed that the SCFA uptake followed first order kinetics and the uptake rate of propionic acid was faster than that of acetic acid, which indicated that a higher ratio of propionic/acetic acid promoted EBPR stability. It was found that with the increase of propionic/acetic acid ratio, the soluble ortho-phosphorus (SOP) release and uptake decreased. However, the SOP removal efficiency was observed to increase linearly from 51.19% (reactor 1~#) to 85.53% (reactor 4~#) and further to 93.99% in reactor 5~#. Apparently, higher ratio of propionic / acetic acid improved phosphorus removal.