基于EFDC模型的表面流人工湿地水力性能和净化效果影响因素分析  

Factors affecting the hydraulic performance and purification efficiency of free-water-surface constructed wetlands based on EFDC model

作　　者：王佳儿 崔远来[1] 张博超 廖斌 贺天忠[2] 郭健[2] WANG Jia’er;CUI Yuanlai;ZHANG Bochao;LIAO Bin;HE Tianzhong;GUO Jian(State key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan 430072,China;Hubei Zhanghe Engineering Management Bureau,Jinmen 448156,China)

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,武汉430072 [2]湖北省漳河工程管理局,荆门448156

出　　处：《农业工程学报》2024年第7期172-181,共10页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目——长江水科学研究联合基金项目(U2040213)。

摘　　要：为探究长宽比、水深和水力负荷对表面流人工湿地水力性能和净化效果的影响及其定量关系,采用EFDC(environmental fluid dynamics Code)模型建立表面流人工湿地水动力-水质耦合模型并对模型进行率定和验证,基于构建的模型设置3因素6水平的全因子模拟试验,通过分析216组试验结果研究湿地长宽比、水深和水力负荷及其交互作用对湿地水力性能和净化效果的影响,进而采用多元非线性回归模型将多因子影响与7个评价指标之间建立定量关系。结果表明:长宽比、水深和水力负荷之间的交互作用对水力性能和净化效果均有显著影响(P<0.05)。构建的参数与评价指标的回归模型说明水力效率、有效容积率和莫里尔离散指数与长宽比呈指数相关,总氮浓度去除率与水深呈指数相关,回归方程的建模决定系数均大于0.9,经试验数据验证的相对误差在20%以下,说明模型是可靠的。研究可为表面流人工湿地设计和运行提供依据。To investigate the effects of aspect ratio,water depth,and hydraulic loading rate(HLR)on the performance of freewater-surface constructed wetlands(FWS CWs)and their quantitative relationships,this study established a hydrodynamicwater quality coupling model for free-water-surface constructed wetlands by Environmental Fluid Dynamics Code(EFDC),and the model was calibrated and validated.Based on the constructed model,a full factor simulation experiment with 3 factors and 6 levels was set up.By analyzing 216 sets of experimental results,the impacts of wetland aspect ratio,water depth,HLR,and their interactions on wetland hydraulic performance and purification effect were studied.Then,a multivariate nonlinear regression model was used to establish a quantitative relationship between the multi-factor impact and 7 indicators.In August and September 2021,wetland tests were conducted at the Hubei Provincial Irrigation Experiment Center Station in Zhanghe Irrigation District,Jingmen City,Hubei Province(30°50'N,112°11'E).A total of 9 free-water-surface constructed wetlands were used for the experiment.Plant species(lotus,water bamboo,cattail)and aspect ratio(2,4,8)were designed as 2 factors with 3 levels each.Tracer tests were used to study the hydraulic characteristics of water flow.The hydraulic performance evaluation indicators included effective volume ratio,hydraulic efficiency,Morril dispersion index(MDI),moment index(MI)and short-circuit indexφ10.The purification effect test mainly reflected the purification effect of wetlands on pollutants by measuring the water quality concentration at the inlet and outlet.Removal rate and mass removal rates per cubic meter were considered as purification efficiency indicators.An EFDC model suitable for free-water-surface constructed wetlands was constructed based on the test data.Based on the EFDC model,a full factor simulation test was conducted with aspect ratio,water depth,and HLR as design factors,with 6 levels for each factor.Regression equations were constructed between

关 键 词：磷 氮 湿地 水力性能 净化效果 EFDC模型 

分 类 号：S156.8[农业科学—土壤学]