节点文献

复合垂直流人工湿地系统除磷研究

Studies on Phosphorus Removal in Integrated Vertical Flow Constructed Wetland

【作者】 张晟

【导师】 吴振斌;

【作者基本信息】 中国科学院研究生院(水生生物研究所) , 环境科学, 2007, 博士

【摘要】 作为欧盟项目“热带、亚热带区域水质改善、回用与水生态系统重建的生物工艺学对策研究”的研究成果,复合垂直流人工湿地系统已经逐步开始应用于富营养化湖泊水体治理。本文以实验室研究为主,结合野外基地实验,在以下几个方面讨论了复合垂直流人工湿地的对磷的净化效率、净化机理,并对维持人工湿地系统的长效安全运行进行了初步的研究。1.通过比较八套组合工艺系统在400-1020mm/d的水力负荷下对磷的净化效率,发现下行流湿地——兼性塘组合工艺对总磷无机磷的平均去除效率最低仅为18.41%和6.95%。对无机磷去除效果最好下行流湿地——上行流湿地组合工艺,即复合垂直流人工湿地系统,去除率达到33.76%。对总磷去除效果最好的推流床——下行流湿地组合工艺,去除率达到40.35%,复合垂直流人工湿地系统对总磷的去除率也达到了39.68%。复合垂直流人工湿地系统对总磷无机磷的去除效率要略高于推流床工艺,推流床与复合垂直流人工湿地系统联用时,推流床后置能够小幅度提高系统的除磷能力,而塘系统与下行流湿地系统联用时,塘系统后置会除磷效果会降低20%以上。2.通过比较两年间六种湿地组合工艺系统不同层次出水中磷含量以及各主要理化因子的变化,发现好氧塘——下行流湿地组合工艺中无机磷的去除效率与溶解氧的含量显著相关(r2=0.994),而下行流湿地——兼性塘组合工艺(r2=0.840)、推流床——下行流湿地组合工艺(r2=0.745)、下行流湿地——推流床湿地组合工艺(r2=0.728)中总磷的去除效率与pH显著相关。在高水力负荷(1200mm/d)下,各套组合工艺系统表层对磷的积累增加,基质磷发生了不同程度的释放。好氧塘——下行流湿地组合工艺对磷的去除效率下降幅度最小,在水流方向上对磷的去除效率持续增加。3.通过对复合垂直流人工湿地系统进行分层采水,发现复合垂直流人工湿地系统上行池在系统除磷效能下降时出现了磷的释放,通过对基质磷总磷、有机磷以及无机磷的分级分离,发现人工湿地系统基质中磷的积累主要是铁磷和钙磷的积累造成。4.通过在实验室建立模拟柱试验的研究,对沸石、无烟煤、页岩、蛭石、陶粒、砾石、钢渣、圆陶粒等人工湿地填料进行筛选,发现钢渣具有最好的除磷效率,实验期间对总磷的去除率高于85%,在进水磷含量低于0.5mg/L的条件下也能保持高的除磷效率。5.通过对官桥人工湿地系统的研究,发现用草皮代替大型湿生植物作为湿地上行池主要植物的切实可行。6.通过人工湿地系统的三角湖工程示范的监测,总结了人工湿地系统在实际工程中运行的成功经验。本文首先比较了不同构型的人工湿地系统除磷的效率,发现复合垂直流人工湿地系统在高水力负荷下具有较好的净化磷的能力。通过比较不同构型组合的人工湿地去除磷的净化空间,得出了人工湿地系统组合的一些重要原则。并通过实验室和野外的结合研究,考察了复合垂直流人工湿地系统除磷的主要机理并深入讨论了复合垂直流人工湿地系统净化效率下降的主要原因,提出了人工湿地除磷效能下降时的解决方案。为了进一步提升复合垂直流人工湿地系统除磷能力,通过实验室模拟柱实验发现钢渣除磷效果最佳,是否能应用于工程实践还有待进一步的试验论证。

【Abstract】 As a new designed constructed wetland developed by the EC project“Water quality improvement in tropical and subtropical areas for reuse and rehabilitation of aquatic ecosystems”, Integrated Vertical Flow Constructed Wetland (IVCW) has been widely used to the rehabiliatation of the eutrophic lake. Laboratory and field researches have been carried out in this dissertation. Performance and mechanism of phosphorus removal were investigated in pilot, medium and large scale. It was discussed how to lengthen the longevity of this kind of constructed wetland and how to keep the high removal performance on phosphorus in this paper. This dissertation concentrated on:1. Eight different combined processes of constructed wetlands were monitored mainly for their phosphorus removal abilities.Among the 8 systems, the best TP removal efficiency took place in plug flow bed-down flow chamber process. 39.68% was observed. The Down flow chamber-stabilization pond process removed the least phosphours, only 18.41% TP and 6.95% IP was removed. The best IP removal efficiency of 33.76% was observed in IVCW. Putting the plug flow after IVCW could minorly enhance the phophorus removal ability, however putting the stabilization pond after down flow chamber would decrease 20% in removing phosphorus.2. The spatial removal differences of six different combined processes were monitored in 2 years. Phosphorus removal efficiency in the stabilization pond-down flow chamber process significantly correlated to the DO value. Phosphorus removal efficiency in the down flow chamber-stabilization pond (r2=0.840), the down flow chamber-plug flow bed (r2=0.745), the plug flow bed- down flow chamber (r2=0.728) significantly correlated to the pH value. Under the high hydraulic load of 1200mm/d, the upper layer of the combined processes accumulated more phosphorus than the bottom. Phosphorus was released from the upper section. Phosphorus removal ability in the stabilization pond-down flow chamber process decreased least, increased along the water flow direction. 3. Spatial outlet water was collected and analysed, the sequential separation of differed form phosphorus in the substrate was also performed. The accumulation of phosphorus in the substrate was mainly casued by the increase of Ca-P, Al-P.4. Eight constructed wetland media, zeolite, anthracite, shale, vermiculite, ceramic filter, gravel, blast furnace, biomaterial ceramic were studied for their phosphorus removal abilities in green house. Blast furnace was the best choice for the high performance removing phosphorus over 85% during the experiment stage even when the inlet phosphorus concentration lower than 0.5mg/L.5. Phosphorus removal in Guanqiao construted wetland was studied, using grass as the upflow chamber plant was a feasible choice.6. Through the practical use of constructed wetland in Sanjiaohu Lake, the experiences of practical use in treating eutrophic lake water were acquired.Phosphorus removal in different combined processed constructed wetlands were investigated, IVCW operates best under high hydrolic load rate and cold climate. Spatial sampling results from different combined processed wetlands revealed some important principles of combination of constructed wetland untis. Laboratory research and field research were performed on mechanisms of phosphorus in IVCW, the method avoiding the decrease of phosphorus removal rate was brought forward. In order to length the lifespan of phosphorus remove, 8 different media were investigated for their phosphorus removal ability. Blast furnace appered the best performance,. The pratical use needs further research.

节点文献中: 

本文链接的文献网络图示:

本文的引文网络