Mechanism and microbial community analysis of anaerobic acid production (VFAs) by low carbon sludge in South China at alkaline condition

doi:10.11949/j.issn.0438-1157.20151230

Abstract

Abstract:

Nowadays, the researches of VFAs production by excess sludge focused mainly on the utilization of the excess sludge from wastewater treatment plant (WWTP) in east and north areas of China, and few on the sludge in south China. Meanwhile, the related on-site experimental research for VFAs production property by sludge from WWTP in south China was rarely reported. Research on VFAs production by excess sludge was conducted at alkaline condition by semi-continuous anaerobic reactor, which was located at Dinghu wastewater treatment plant in Zhaoqing, Guangdong Province. The results showed that great hydrolysis and acidification properties of the system could be achieved at alkaline condition (pH 10.0). The percentage of VFAs-COD/SCOD was 73.89% in average, which was about 2%—15% higher than that of existing similar researches. Meanwhile, only small amount of polysaccharide and protein were accumulated (5%—15% of SCOD). Acetic acid was the main component of VFAs with the proportion of 51.43%. And the dominant microbial species in the system were all nearly acid production microorganisms including Acetoanaerobium sp., Clostridiales bacterium Z-810, Proteinivorax tanatarense strain Z-910 and Tissierella sp., among which Acetoanaerobium sp. and Clostridiales bacterium Z-810 were not reported in other similar researches. The excess sludge reduction rate of 33.5% could be achieved.

Key words: excess sludge, alkaline fermentation, SCOD, VFA, sludge reduction, microbial community

摘要：

目前,我国利用剩余污泥产挥发性脂肪酸(VFAs)的碳源化研究主要集中在对华东和北方地区污水厂污泥的利用,而采用华南地区污水厂剩余污泥进行产酸的研究较少,且对其开展实际现场产酸特性的研究更是少见报道。采用半连续式厌氧产酸反应器,对广东省肇庆市鼎湖区污水处理厂剩余污泥产挥发性脂肪酸的系统特性进行了试验研究。研究结果表明,系统在碱性条件下(pH 10.0)具有良好的水解产酸性能。VFAs对应的COD(VFAs-COD)占SCOD的比重较大,平均占比73.89%,高于现有同类研究结果2%~15%。同时仅伴随着少量的多糖和蛋白质积累(对应的COD占SCOD的比重为5%~15%)。乙酸为主要的VFAs组成成分,平均占比51.43%,系统优势菌几乎全部为产酸菌,包括Acetoanaerobium sp.、Clostridiales bacterium Z-810、Proteinivorax tanatarense strain Z-910、Tissierella sp.,其中Acetoanaerobium sp.、Clostridiales bacterium Z-810在同类研究中暂无报道。系统产酸过程中可实现33.5%的污泥减量率。

关键词: 剩余污泥, 碱性产酸, 溶解性有机物, 挥发性脂肪酸, 污泥减量, 菌群

CLC Number:

X703

YAO Chuang, LIU Hui, LUO Xiaodong, YUE Jianxiong, LI Shiyao, CHEN Dazhi. Mechanism and microbial community analysis of anaerobic acid production (VFAs) by low carbon sludge in South China at alkaline condition[J]. CIESC Journal, 2016, 67(4): 1565-1571.

姚创, 刘晖, 罗晓栋, 岳建雄, 李诗瑶, 陈大志. 华南地区低有机质污泥碱性厌氧产酸(VFAs)性能机理与菌群分析[J]. 化工学报, 2016, 67(4): 1565-1571.

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