摘要
铁碳和沸石粒径对人工湿地基质的孔隙度具有影响,二者不同的填充方式将影响人工湿地中水流的不饱和流动、曝气后的DO分布、植物吸收作用以及微生物活动,进而影响污水中硝化与反硝化进程,影响污水处理效果.本研究通过在温室构建潜流人工湿地系统装置,均为间歇曝气,设立不同填料的填充配比和填充顺序,分别为:添加20%铁碳+80%沸石(其中铁碳在上层沸石在下层记为T2F8,铁碳在下层沸石在上层记为F8T2,下同)、40%铁碳+60%沸石(记为T4F6和F6T4)、60%铁碳+40%沸石(记为T6F4和F4T6),以添加100%沸石为对照组(F),探究基质的填充方式对人工湿地系统中污水处理的影响.结果表明,与铁碳填充于表层的湿地相比,铁碳填充于底层能显著提高人工湿地中pH与DO含量(p<0.05),并显著提高了对NH_(4)^(+)-N和TN的去除率(p<0.05),且当铁碳占比为20%时对NH_(4)^(+)-N和TN的去除效果最好;铁碳-沸石填充体积比为4∶6时人工湿地对于COD的去除效果提升最为显著(p <0.05).典型周期内,铁碳填充于底层且铁碳占比越少时能显著改善湿地中DO环境并显著提升湿地脱氮效率(p<0.05).综合而言,铁碳填充在底层且铁碳-沸石体积比为2∶8时的铁碳-沸石人工湿地(F8T2)水质净化效果最好.
The different granularity between Fe-C and zeolite,determines the porosity of the constructed wetland.Different filling methods of Fe-C and zeolite will affect the unsaturated flow of current,DO distribution after aeration,plant absorption and microbial activities in the constructed wetland,then affect the process of nitrification and denitrification in sewage,further influence of sewage treatment efficiency.In this study,we built subsurface flow constructed wetland system with intermittent aeration device in the greenhouse,the filling ratio and filling sequence were set as follows:Add 20%Fe-C+80% zeolite(Fe-C in the surface layer,zeolite in the bottom layer is recorded as T2F8,Fe-C in the bottom layer,zeolite in the surface layer is recorded as F8T2,the same below),40%Fe-C+60%zeolite(denoted as T4F6 and F6T4),60% Fe-C+40% zeolite(denoted as T6F4 and F4T6),and 100%zeolite added as the control group(F)were used to explore the effect of substrate filling method on sewage treatment in constructed system.The results showed that Fe-C filling in the bottom layer increase the pH and DO contents in the constructed wetland(p<0.05),and significantly increase the removal rate of NH_(4)^(+)-N and TN(p<0.05).When the Fe-C filling ratio was 20%,the removal efficiencies of NH_(4)^(+)-N and TN were optimal.The removal rate of COD in constructed wetland was significantly improved(p<0.05)when the filling volume ratio of Fe-C to zeolite was 4:6.In a typical period,Fe-C filled in the bottom layer and occupy less proportion,DO and nitrogen removal efficiency of the wetland could be significantly improved(p<0.05).In general,F8T2 with Fe-C filling in the bottom layer and the volume ratio of Fe-C to zeolite was 2∶8 has the best water purification effect.
作者
马容真
郝庆菊
翁思佳
陈柯沁
罗师旭
江长胜
MA Rongzhen;HAO Qingju;WENG Sijia;CHEN Keqin;LUO Shixu;JIANG Changsheng(Key Laboratory of Eco-environments in Three Gorges Reservoir Region of Ministry of Education,College of Resources and Environment,Southwest University,Chongqing 400715;Institute of Innovation and Entrepreneurship,Southwest University,Chongqing 400715)
出处
《环境科学学报》
CAS
CSCD
北大核心
2023年第9期130-141,共12页
Acta Scientiae Circumstantiae
基金
国家自然科学基金项目(No.41977186)
重庆市基础研究与前沿探索项目(No.cstc2018jcyjAX0476)
重庆市大学生创新训练项目(No.S202210635324)。
关键词
铁碳-沸石人工湿地
基质填充方式
间歇曝气
废水处理
Fe-C and zeolite constructed wetland
substrate filling method
intermittent aeration
wastewater treatment
