摘要
人工湿地是温室气体的重要排放源,为了探索减少其温室气体排放的措施,通过在温室内构建了空白-人工湿地(湿地Ⅰ)、铁矿石-人工湿地(湿地Ⅱ)、生物炭-人工湿地(湿地Ⅲ)和铁矿石+生物炭-人工湿地(湿地Ⅳ)4组湿地,研究了铁矿石和生物炭基质的添加对潜流人工湿地污水处理效果和温室气体排放的影响。结果表明,4组湿地的平均出水COD分别是(34.99±1.60)、(35.57±1.69)、(30.87±1.65)和(27.52±2.37)mg·L^(−1),COD去除率均达到90%以上。4组湿地系统的出水平均TN浓度分别是(24.75±0.96)、(24.99±0.72)、(15.04±0.61)和(15.63±0.61)mg·L^(−1),湿地Ⅲ和湿地Ⅳ的TN平均去除率分别为65.73%和64.41%,均高于湿地Ⅰ(43.61%)和湿地Ⅱ(43.08%)。和TN类似,4组湿地系统出水NH_(4)^(+)-的-N去除率分别是45.04%、43.92%、67.52%和65.19%。铁矿石和生物炭的添加对于系统中CH4和N2O的减排也有一定作用,以1 g·m−2 CO2的GWP为1,湿地Ⅱ和湿地Ⅲ系统排放CH4和N2O所产生的综合GWP分别是69.88和22.73,相较于湿地Ⅰ(103.36)分别减少了32.39%和78.01%。湿地Ⅳ排放CH4和N2O所产生的综合GWP与单独添加生物炭的湿地Ⅲ相似,GWP为24.62。生物炭的添加相较于铁矿石具有较好的污水处理效果,且具有较低的CH4和N2O排放量。铁矿石生物炭联合添加的湿地中生物炭起主要的污染物去除和温室气体减排作用。以上研究结果可为人工湿地的改进提供有效建议。
Constructed wetland is an important source of greenhouse gas emissions. In order to explore measures to reduce their greenhouse gases emissions, in this study, four groups of wetlands, including blank constructed wetland(wetland Ⅰ), hematite constructed wetland(wetland Ⅱ), biochar constructed wetland(wetland Ⅲ) and hematite-biochar constructed wetland(wetland Ⅳ) were built to investigate the effect of hematite or biochar addition on the sewage treatment and greenhouse gas emissions of subsurface flow constructed wetlands. The results showed that the average effluent COD concentrations of the four wetlands were(34.99±1.60),(35.57±1.69),(30.87±1.65) and(27.52±2.37) mg·L-1, respectively, and all the COD removal rates reached higher than 90%. The average TN concentrations of the four wetland systems were(24.75±0.96),(24.99±0.72),(15.04±0.61) and(15.63±0.61) mg·L-1, respectively, and the average TN removal rates of wetland Ⅲ and wetland IV were 65.73% and 64.41%, respectively, both of them were higher than those of wetland Ⅰ(43.61%) and wetland Ⅱ(43.08%). Similar to TN, the N H4+-N removal rates of the four wetland systems were45.04%, 43.92%, 67.52% and 65.19%, respectively. The addition of hematite-biochar also had a certain effect on the reduction of CH4 and N2 O emissions in the system. With a GWP of 1 g·m-2 CO2 as 1, the average integrated global warming potential(GWP) values of the wetland Ⅱ and wetland Ⅲ systems were 69.88 and22.73, respectively, and they decreased by 32.39% and 78.01% compared with wetland(103.36), respectively.The GWP value of the CH4 and N2 O emissions of wetland Ⅳ was similar to that of wetland Ⅲ with the addition of biochar alone, which was 24.62. Compared with hematite, the addition of biochar caused better sewage treatment effect and lower CH4 and N2 O emissions. The biochar in the hematite-biochar wetland plays a major role in removing pollutants and reducing greenhouse gas emissions. This study can provide effective suggestions for the improvement of constructed wetlands.
作者
邹旭青
郝庆菊
赵茂森
陈世杰
赵仲婧
熊维霞
曾唯
江长胜
ZOU Xuqing;HAO Qingju;ZHAO Maosen;CHEN Shijie;ZHAO Zhongjing;XIONG Weixia;ZENG Wei;JIANG Changsheng(State Cultivation Base of Eco-Agriculture for Southwest Mountainous Land,College of Resources and Environment,Southwest University,Chongqing 400715,China;Institute of Hanhong,Southwest University,Chongqing 400715,China)
出处
《环境工程学报》
CAS
CSCD
北大核心
2021年第2期588-598,共11页
Chinese Journal of Environmental Engineering
基金
重庆市基础研究与前沿探索项目(cstc2018jcyjAX0476,cstc2019jcyj-msxmX0425)
国家自然科学基金面上项目(41977186)
重庆市大学生创新训练项目(S201910635147)。
关键词
潜流人工湿地
铁矿石
生物炭
污染物去除
温室气体
subsurface constructed wetlands
hematite
biochar
pollutant removal
greenhouse gases
