不同发酵方式对污泥厌氧发酵性能的影响及其发酵液利用

摘要

In order to study the effect of different fermentation styles on the waste activated sludge (WAS) anaerobic fermentation performance and the utilization of fermentation liquor by microorganism. The WAS were fermented in the Ca(OH)2(pH=10±0.2),Ca(OH)2+NaCl(pH=10±0.2), FNA(pH=5.5±0.2), PMS, SDBS and naturally fermentation system, and the fermentation liquor was used to de-nitrification of biology. Different indicators were analyzed respectively such as dissolution of organic matters (SCOD), short chain volatile fatty acids (SCFAs), soluble protein, soluble polysaccharide, key enzyme (hydrolase and coenzyme420) and NO3--N. The results showed that the hydrolytic acidification performance and fermented liquid utilization of six fermentation systems had significant difference. The maximal values of SCOD, SCFAs, hydrolase activity and sludge reduction appeared at Ca(OH)2+NaCl fermentation system, and Ca(OH)2 fermentation system was followed, but the naturally fermentation system was minimum. Although the protein and polysaccharide was abundant in the FNA fermentation system as same as Ca(OH)2+NaCl fermentation system, but lower hydrolase and higher F420 activity led to the lower SCFAs accumulation. The de-nitrification tests showed that the fermented liquid from Ca(OH)2 and Ca(OH)2+NaCl fermentation systems had a remarkable de-nitrification effect and large of NO2--N accumulation which was similar to sodium acetate, but the fermented liquid from FNA, PMS and SDBS fermentation systems could not be well used by microorganism because of large of poisonous substance.%为了研究不同发酵方式对剩余污泥厌氧发酵性能影响及微生物对其发酵液的利用情况,将剩余污泥分别在 Ca(OH)2(pH=10±0.2),Ca(OH)2+NaCl(pH=10±0.2),游离亚硝酸盐(FNA)(pH=5.5±0.2),单过硫酸氢钾复合盐(PMS),十二烷基苯磺酸钠(SDBS)及自然条件下进行发酵,发酵后期将发酵液用于生物脱氮研究,分别对发酵系统内的剩余污泥溶液化(SCOD)、溶解性蛋白质、溶解性多糖、可挥发性短链脂肪酸(SCFAs)和关键酶(水解酶和辅酶420)、NO3--N 等指标进行分析.结果表明,6个发酵系统中,剩余污泥的水解酸化性能及发酵液利用具有显著的差别,其中 Ca(OH)2+NaCl 发酵系统中 SCOD、SCFAs、水解酶、污泥减量效果等最佳,Ca(OH)2发酵系统次之,自然条件发酵系统最弱.同时发现,FNA 发酵系统中蛋白质和多糖含量较高,但是由于水解酶活性较低,F420活性最高,导致较低的 SCFAs 积累量.发酵液作为碳源进行生物脱氮试验研究表明,以 Ca(OH)2及 Ca(OH)2+NaCl 发酵系统中的发酵液作为碳源具有良好的脱氮效果,与乙酸钠做为碳源效果相似,同时出现 NO2--N 积累现象,但是 FNA, PMS, SDBS 发酵系统的发酵液由于存在大量的消毒剂等化学物质导致生物利用性较差.