进水碳氮比对表面流人工湿地脱氮效果及途径的影响研究  

Study on the Effect of Influent Carbon-Nitrogen Ratio on the Effect and Pathway of Denitrification in Surface Flow Constructed wetlands

作　　者：严春敏 朱立琴[3] 张海阔 孙玮 王玲 李一平[1,2] YAN Chunmin;ZHU Liqin;ZHANG Haikuo;SUN Wei;WANG Ling;LI Yiping(College of Environment,Hohai University,Nanjing 210098,China;Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes,Ministry of Education,College of Environment,Hohai University,Nanjing 210098,China;College of Agricultural Science and Engineering,Hohai University,Nanjing 210098,China;Yancheng Water Affairs Group Co.,Ltd,Yancheng 224007,China)

机构地区：[1]河海大学环境学院,江苏南京210098 [2]河海大学浅水湖泊综合治理与资源开发教育部重点实验室,江苏南京210098 [3]河海大学农业科学与工程学院,江苏南京210098 [4]盐城市水务集团有限公司,江苏盐城224007

出　　处：《水处理技术》2024年第12期120-126,共7页Technology of Water Treatment

基　　金：国家自然科学基金项目(52079038,51879082);中央高校建设世界一流大学(学科)和特色发展引导专项资金资助;环境学院研究生科研与实践创新计划项目。

摘　　要：进水碳氮比(C/N)是人工湿地脱氮的重要影响因素之一,本研究基于人工湿地小试系统,研究了不同进水C/N条件下表面流人工湿地对污染物去除效果以及系统分析了人工湿地中植物、土壤及微生物三个关键组成要素在氮去除过程中的作用和影响。结果表明,各实验组对NH_(4)^(+)-N(95.91%~96.83%)、NO_(3)^(-)-N(64.75%~99.44%)、TN(76.36%~95.30%)和COD(88.54%~93.01%)都有较好的去除效果。提高C/N能够显著提升人工湿地NO_(3)^(-)-N、TN和COD的去除效果(P<0.05)。总体而言,进水C/N为4时对NH_(4)^(+)-N(95.91%)、NO_(3)^(-)-N(99.44%)和TN(95.30%)都有较好的去除效果。湿地土壤和植物对氮的平均去除占系统氮去除量的6.41%~10.45%和9.23%~14.11%,忽略氨挥发过程,通过质量平衡计算得出微生物作用在系统氮去除的占比为51.43%~77.74%,表明微生物转化脱氮居主导地位,其中进水中投加碳源的人工湿地系统微生物作用占比提高了36.01%~51.16%,C/N=8时,微生物作用占比最大。本研究为表面流人工湿地的设计以及最佳进水C/N的选择提供了理论基础,脱氮途径的定量化解析对深入理解碳源对人工湿地氮去除机制的影响以及提高氮素去除率具有重要的指导意义。The carbon-to-nitrogen ratio(C/N)of influent is one of the important influencing factors for nitrogen removal in constructed wetlands.In this study,based on a small-scale experimental system of constructed wetlands,the pollutant removal efficiency of surface flow constructed wetlands under different influent C/N conditions and the roles and impacts of three key components,i.e.,plants,soil,and microorganisms,in nitrogen removal were investigated.The results showed that all experimental groups had good removal efficiencies for NH_(4)^(+)-N(95.91%~96.83%),NO_(3)^(-)-N(64.75%~99.44%),TN(76.36%~95.30%),and COD(88.54%~93.01%).Increasing C/N significantly improved the removal efficiencies of NO_(3)^(-)-N,TN,and COD(P<0.05).Generally,when the influent C/N was 4,good removal efficiencies were achieved for NH_(4)^(+)-N(95.91%),NO_(3)^(-)-N(99.44%),and TN(95.30%).The average nitrogen removals by wetland soil and plants accounted for 6.41%~10.45% and 9.23%~14.11%of the total nitrogen removal,respectively.Neglecting the ammonia volatilization process,the proportion of nitrogen removal by microorganisms in the system was calculated to be 51.43%~77.74% through mass balance calculation,indicating that microbial transformation was the dominant nitrogen removal pathway.Among them,the proportion of microbial action in the constructed wetland system with added carbon source in influent increased by 36.01%~51.16%.When C/N=8,microbial action accounted for the largest proportion.This study provides a theoretical basis for the design of surface flow constructed wetlands and the selection of optimal influent C/N,and the quantitative analysis of nitrogen removal pathways has important guiding significance for understanding the influence of carbon source on the nitrogen removal mechanism of constructed wetlands and improving nitrogen removal efficiency.

关 键 词：表面流人工湿地 碳氮比 污染物去除效果 氮去除途径 

分 类 号：X524[环境科学与工程—环境工程]