| 1 | 人工湿地系统不同流段中氮的去除效果研究显示文摘2015年8月13~19日,通过模拟实验,在植物生长期,设置不同初始进水总氮浓度,研究不同流段人工湿地中氮的去除效果,并探讨了其作用机理。设置2组由表面流段—垂直流段—水平流段组成的模拟装置,其有效长度为3.6 m,宽度为0.5 m,深度为0.85 m,炉渣基质填充高度为0.65 m,种植美人蕉(Canna indica),采集3个流段15~20 cm、30~35 cm和45~50 cm(以距离基质表层以下深度)深度以及表面流段上覆水的水样,分析测定水中铵态氮和硝态氮等指标的含量。研究结果表明,各流段人工湿地系统中,初始进水浓度影响铵态氮的去除率和去除负荷,而由于充足的碳源,初始进水浓度对硝态氮的去除率影响较小,去除率都达到95%以上。水中有机碳源充足且易分解,可以有效提高湿地系统的反硝化速率和脱氮效果。在各流段人工湿地系统中,延长水体在湿地系统中的停留时间,有利于铵态氮的去除。因此,延长停留时间和拥有充足且易分解的碳源,有利于不同流段人工湿地中氮的去除。在低初始进水浓度(总氮质量浓度为85.4 mg/L)条件下,表面流段对铵态氮去除率最高,其次为垂直流段,水平流段对铵态氮的去除率最低。在高初始进水浓度(总氮质量浓度为148.3mg/L)条件下,3个流段对铵态氮的去除效果差别不大。湿地植物吸收及其代谢、微生物代谢、基质物理化学作用,以及进水负荷等共同引起水中p H的变化;进水方式和湿地植物代谢是引起湿地系统中氧化还原电位变化的主要原因。 | 张燕 刘雪兰 王月明 井庆川 阎佩佩 刘瑞亭 石天虹 魏祥法 | 2017 | 湿地科学2017,15,1: | 6 |
| 3 | Modeling on Residence Time Distribution in Subsurface Flow Constructed Wetlands by Multi Flow Dispersion Model显示文摘As an important design factor for constructed wetlands,hydraulic retention time and its distribution will affect the treatment performance.Instantaneously injected sodium chloride tracers were used to obtain residence time distributions of the lab scale subsurface flow constructed wetland.Considering the presence of trailing and multiple peaks of the tracer breakthrough curve,the multi flow dispersion model(MFDM)was used to fit the experimental tracer breakthrough curves.According to the residual sum of squares and comparison between the experimental values and simulated values of the tracer concentration,MFDM could fit the residence time distribution(RTD)curve satisfactorily,the results of which also reflected the layered structure of wetland cells,thus to give reference for application of MFDM to the same kind of subsurface flow constructed wetlands. | ZHANG Tao SONG Xinshan LU Shoubo YAN Denghua | 2010 | 湿地科学2010,8,3: | 2 |