基于猪场废水脱氮的典型木质素降解中间产物反硝化性能  

Denitrification performance of typical lignin degradation intermediates for biological nitrogen removal from swine wastewater

作　　者：熊鑫 刘鹏 王云燕 唐佳 唐溪 唐崇俭 XIONG Xin;LIU Peng;WANG Yunyan;TANG Jia;TANG Xi;TANG Chongjian(School of Metallurgy and Environment,Central South University,Changsha 410083;Chinese National Engineering Research Center for Control and Treatment of Heavy Metal Pollution,Central South University,Changsha 410083)

机构地区：[1]中南大学冶金与环境学院,长沙410083 [2]国家重金属污染防治工程技术研究中心,长沙410083

出　　处：《环境科学学报》2022年第10期223-232,共10页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.U21A20294,51878662)。

摘　　要：猪场废水高效生物脱氮通常面临碳源不足的问题,秸秆在猪场周边广泛存在,是废水脱氮的潜在碳源来源,但其中的木质素难以被生物降解与利用.选取木质素降解过程的典型中间产物肉桂酸、对香豆酸和阿魏酸为研究对象,探究了其用作碳源的反硝化脱氮性能,以期为猪场废水脱氮过程秸秆“返碳”利用提供理论依据.批次试验表明,当C/N由6依次降低至3时,肉桂酸、对香豆酸和阿魏酸作为碳源时的最大比反硝化速率测定值分别为9.4、8.6、1.1 mg·g^(-1)·h^(-1).采用Haldane模型拟合,计算出这3种中间产物作为碳源时的最大比反硝化活性分别为20.7、17.0和1.6 mg·g^(-1)·h^(-1).肉桂酸用作反硝化碳源的潜力大于对香豆酸,阿魏酸则难以作为碳源进行反硝化脱氮.长期试验表明,随着反应器进水C/N由3升高至6,肉桂酸和对香豆酸的硝酸盐去除率分别稳定在90%和85%左右.高通量测序结果表明,肉桂酸组的污泥中典型反硝化细菌Thauera的丰度高于对香豆酸组,故反硝化效果更好.综上所述,定向调控木质素降解为肉桂酸有望缓解猪场废水生物脱氮过程碳源不足的问题,进而为猪场“种养一体化”思路提供理论依据.Low level in biodegradable carbon is one of the bottlenecks that limits the application of denitrification in the treatment of swine wastewater.As a potential biodegradable source,straw widely exists around swine,but the lignin of straw is difficult to be biodegraded and utilized.Therefore,three typical intermediates of lignin degradation,cinnamic acid,p-coumaric acid and ferulic acid,were selected in this study to explore their characteristics as carbon sources for denitrification.The batch experiments showed that when the C/N decreased from 6 to 3,the maximum specific denitrification activities of cinnamic acid,p-coumaric acid and ferulic acid were respectively for 9.4,8.6 and 1.1 mg·^(-1)·h^(-1).The analysis of Haldane model revealed that the maximum specific denitrification activities of these three intermediate products as carbon sources were 20.7,17.0 and 1.6mg·^(-1)·g^(-1)·h^(-1).That is to say,cinnamic acid was more suitable as a carbon source for denitrification than coumaric acid,while ferulic acid is difficult to be a carbon source for denitrification.The performance of long-term operated reactor showed that as the C/N increased from 3 to 6,the nitrate removal efficiency of cinnamic acid and p-coumaric acid groups remained stable respectively at about 90%and 85%.High-throughput sequencing analysis showed that the abundance of typical denitrifying bacteria Thauera in cinnamic acid group was higher than that in p-coumaric acid group.Thus,the denitrification performance was better.This study aimed to provide theoretical basis for the targeted regulation of lignin degradation to cinnamic acid and the"carbon returning"utilization during swine wastewater treatment.

关 键 词：反硝化 猪场废水 有机碳源 木质素 生物降解 

分 类 号：X703[环境科学与工程—环境工程]