基于铁基质高效催化还原污水中硝酸盐氮的实验研究  

Experimental study on effective nitrate removal from sewage by ZVI-based catalyzed reduction

作　　者：李德生[1,2] 张超 邓时海 胡智丰[1] 李金龙 刘元辉 LI Desheng;ZHANG Chao;DENG Shihai;HU Zhifeng;LI Jinlong;LIU Yuanhui(School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, China;Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, Beijing 100044, China)

机构地区：[1]北京交通大学土木建筑工程学院,北京100044 [2]水中典型污染物控制与水质保障北京市重点实验室,北京100044

出　　处：《化工学报》2019年第3期1065-1074,共10页CIESC Journal

基　　金：国家自然科学基金项目(51778040;51278034)

摘　　要：污水厂排水中硝酸盐氮(NO_3~–-N)浓度偏高,难利用常规生物脱氮工艺实现NO_3~–-N的深度脱除。以铁基质高效催化脱氮载体为污水中NO_3~–-N的脱除材料,探究不同铁基质催化活性、pH和NO_3~–-N浓度等对污水中NO_3~–-N去除的影响及机制。研究结果表明:添加催化剂D的铁基质高效催化脱氮载体可脱除92.23%的NO_3~–-N,调节污水为酸性至中性条件时,其NO_3~–-N去除率均可达到92.09%以上,且氨氮(NH_4^+-N)积累量先升高后降低;当污水为碱性条件时,NO_3~–-N的去除率亦可达86.13%以上,且在碱性条件时无NH_4^+-N积累;原水中NO_3~–-N的浓度变化(20～70 mg·L^(-1))对铁基质高效催化脱氮载体的脱氮性能影响较小,NO_3~–-N去除率均达到96.11%以上。与催化剂A、B和C相比,添加催化剂D的铁基质高效催化脱氮载体脱氮速率最快,NO_3~–-N降解反应过程符合一级反应动力学方程,反应速率常数k=0.0170 min^(-1)。It remains difficult to achieve effective nitrate removal with conventional biological nitrogen removal processes, for the high NO^-3-N concentration and low organic carbon in tail water from WWTP. Thus, ZVI-based catalyzed reduction was developed and applied in this study. The influence of catalytic activity of the catalysts, pH and NO^-3-N concentration on nitrate reduction by ZVI-based catalyzed reduction was studied, and the reaction mechanisms was investigated. The results show that the high-catalytic catalytic denitrification carrier with catalyst D can remove 92.23% of NO^-3-N, and the NO^-3-N removal rate can reach 92.09% when the wastewater is acidic to neutral. The NO^-3-N removal efficiency of above 86.13% was also achieved even under alkaline conditions, and no NH +4-N accumulation was found. Increasing in NO^-3-N concentration (20-70 mg · L^-1 ) showed little impact on nitrate reduction efficiency (remaining ≥96.11%). The nitrogen removal efficiency by ZVI-based catalyzed reduction in the presence of catalyst D obtained the highest speed when compared to catalysts A, B and C, and the reduction reaction was in keeping with the first-order kinetics equation with a calculated reaction rate constant of k =. Experimental study on effective nitrate removal from sewage by ZVI-based catalyzed reduction[J]. CIESC Journal, 2019, 70(3): 1065-1074 0.0170 min^-1.

关 键 词：污水厂排水 硝酸盐氮 零价铁 铁基质高效催化脱氮载体 催化剂 双金属 催化还原 反应动力学 

分 类 号：X703[环境科学与工程—环境工程]