Lee Y H, Chung Y-C, Jung J-Y
Center for Environmental Technology Research, Korea Institute of Science and Technology, 39-1 Hawolgok-Dong, Sungbuk-Gu, Seoul 136-791, South Korea.
Water Sci Technol. 2008;58(7):1529-34. doi: 10.2166/wst.2008.496.
Slow degradation of swine wastewater mainly due to the particulate and recalcitrant organic matters is a main disadvantage of anaerobic digestion leading to very long solids retention time. Therefore, to accelerate hydrolysis known as the rate-limiting step of the overall digestion process, chemical treatment processes under various acidic and alkaline conditions as well as enzymatic treatment processes using cellulase and protease enzymes were tested for the hydrolysis of the swine wastewater. The effectiveness of various treatment processes was compared mainly by means of an increment of soluble organics in the treated swine wastewater. Among various treatment processes tested in this study, cellulase enzymatic treatment resulted in the most efficient hydrolysis of the swine wastewater. For the cellulase enzymatic hydrolysis, the observed hydrolytic constant value was 0.42 d(-1) and 26.6% of soluble organics in the swine wastewater increased within 12 hr. Compared to untreated swine wastewater, pre-treated swine wastewater by cellulase enzymatic process showed 10.7% higher anaerobic digestibility at the end of 20 d incubation and 29% higher initial methane production rate. These results further confirmed the transformation of particulate and recalcitrant organic compounds in the swine wastewater into soluble and relatively easily biodegradable organic products by the cellulase enzymatic hydrolysis.
猪废水降解缓慢主要是由于颗粒状和难降解有机物，这是厌氧消化的一个主要缺点，导致固体停留时间非常长。因此，为了加速水解这一整体消化过程的限速步骤，测试了各种酸性和碱性条件下的化学处理工艺以及使用纤维素酶和蛋白酶的酶处理工艺对猪废水的水解效果。主要通过处理后的猪废水中可溶性有机物的增加来比较各种处理工艺的有效性。在本研究测试的各种处理工艺中，纤维素酶酶处理对猪废水的水解效果最为显著。对于纤维素酶酶水解，观察到的水解常数为0.42 d(-1)，猪废水中26.6%的可溶性有机物在12小时内增加。与未处理的猪废水相比，经纤维素酶酶处理的猪废水在20天培养结束时的厌氧消化率高10.7%，初始甲烷产生率高29%。这些结果进一步证实了纤维素酶酶水解将猪废水中的颗粒状和难降解有机化合物转化为可溶性且相对易生物降解的有机产物。
