人工湿地集成系统的构建及其水质净化效果研究

发布时间：2018-08-26 11:39

【摘要】：人工湿地(Constructed wetland)具备基建成本低,效益高等特点,同时兼备经济、社会和生态价值,是处理污水的理想途径,近几十年来成为研究热点。人工湿地是对自然湿地结构和功能的模拟,其净化机理是通过植物、基质和微生物之间的相互作用,经物理、化学和生物过程实现对污染物的去除。目前广泛用于生活污水、工业污水、水产养殖外排水与农业点源污染和面源污染以及其他富营养化水体的治理。但是人工湿地在实际运行中存在许多问题,例如:占地面积大,长期运行稳定性较差,有机物去除效率低以及易堵塞等。针对人工湿地运行中存在的问题,本文构建了人工湿地和人工湿地-生物滤池(Biological filter)处理工艺,并对净化养殖外排水效果进行了研究。以期充分结合利用两者的优点实现养殖外排水的高效净化,为构建养殖外排水净化理论提供一定的参考价值和技术支撑。主要结论如下:(1)以亚克力材料构建了由下向流池、上向流池、沉淀池等组成的复合垂直流人工湿地(Integrated vertical-flow constructed wetland,IVCW),长、宽和高为100.00×60.00 cm×100.00 cm,对海水养殖外排水进行非连续进水净化研究。结果表明IVCW对养殖外排水中的高锰酸钾指数(CODMn)、氨氮(NH4+-N)、总氮(TN)和总磷(TP)去除效果良好。实验期间出水的基本参数如下,温度为(26.62±0.64)℃;溶氧为(5.79±0.28)mg/L,pH为7.67±0.05。对污染物的净化效果如下,每日CODMn出水浓度为(3.7±0.8)mg/L,平均去除率为(70.54±7.8)%;磷酸盐浓度出水浓度平均为(0.03±0.01)mg/L,平均去除率为(93.34±1.07)%。总磷平均浓度为(0.06±0.01)mg/L,平均去除率为(91.56±0.91)%。氨氮的平均去除率为(78.52±4.37)%,最高去除率为85.36%。总氮出水浓度最后稳定在1.07 mg/L上下,平均去除率为(47.24±4.33)%。其中CODMn符合《海水养殖水排放要求》(SC/T 9103-2007)一级标准;pH和氨氮符合《渔业水质标准》(GB 11607-89)和《海水养殖水排放要求》(SC/T 9103-2007)一级标准。(2)为探究人工湿地-生物滤池组合工艺对循环水养殖中污染物的净化作用,构建了复合式人工湿地系统,系统由养殖池、生物滤池、贮水池、人工湿地和沉淀池等串联而成。人工湿地和生物滤池内部均为分段式设计。整套系统占地面积和体积分别为1.30 m2和910.00 L。人工湿地和生物滤池分别以珊瑚石、砂石和生化滤球、爆炸棉为填料。研究结果表明,复合人工湿地系统在循环水养殖中对CODMn、磷酸盐、总磷、氨氮和总氮净化效果良好,每日出水浓度稳定。淡水系统每日出水CODMn为(3.2±0.8)mg/L;磷酸盐变为(0.08±0.01)mg/L;TP平均为(0.10±0.01)mg/L;海水系统每日出水CODMn为(5.3±0.7)mg/L;磷酸盐为(0.05±0.01)mg/L;TP为(0.07±0.01)mg/L。NH4+-N平均出水浓度为(0.04±0.02)mg/L,淡水和海水系统的TN平均出水浓度分别为(4.51±0.77)mg/L和(4.62±0.63)mg/L。pH,CODMn,P、TP、TN均符合《淡水池塘养殖水排放要求》(SC/T 9101-2007)和《海水养殖水排放要求》(SC/T 9103-2007);氨氮符合《渔业水质标准》(GB 11607-89)。复合式人工湿地系统空间利用率低,有效面积和有效体积占较低,分别为43.85%和36.92%。系统管网过长导致污染物在水流管网内壁堆积,影响流速,导致出水水质不稳定。(3)为解决复合式人工湿地净水系统运行中存在的问题,本实验设计构建了集成式人工湿地系统中。处理单元小型化,直接并接省去了连接管路,有效面积比和有效体积比接近100.00%。人工湿地和生物滤池的填料种类及方式与复合式人工湿地系统相同,内部采用分布式设计。研究结果表明,在实验期间两套系统对污染物的净化能力较差,各个污染物浓度波动范围较大。系统1每日出水CODMn为(6.2±1.2)mg/L;磷酸盐为(0.06±0.02)mg/L;TP为(0.08±0.02)mg/L;系统2每日出水CODMn为(4.6±0.8)mg/L;磷酸盐为(0.03±0.02)mg/L;TP为(0.05±0.02)mg/L。统1中NH4+-N平均浓度为(2.36±1.04)mg/L,TN平均浓度为(7.34±2.50)mg/L。系统2中NH4+-N平均值为(2.65±0.96)mg/L,TN平均浓度为(7.29±1.79)mg/L。pH,P,CODMn符合《海水养殖水排放要求》(SC/T 9103-2007),氨氮不符合要求。
[Abstract]:Constructed wetland is an ideal way to treat wastewater with low cost and high benefit, and it has economic, social and ecological value. In recent decades, constructed wetland has become a research hotspot. At present, it is widely used in the treatment of domestic sewage, industrial sewage, aquaculture drainage, agricultural point source pollution, non-point source pollution and other eutrophic water bodies. In view of the problems existing in the operation of constructed wetlands, this paper constructs the treatment process of constructed wetlands and constructed wetlands-biological filters, and studies the effect of purifying aquaculture drainage. The main conclusions are as follows: (1) An integrated vertical-flow constructed wetland (IVCW) consisting of downstream, upstream and sedimentation ponds was constructed with acrylic materials. The length, width and height of the constructed wetland were 100.00 The results showed that the removal efficiency of potassium permanganate index (CODMn), ammonia nitrogen (NH4 + - N), total nitrogen (TN) and total phosphorus (TP) in aquaculture effluent by IVCW was good. The basic parameters of effluent during the experiment were as follows: the temperature was (26.62 (0.64)), the dissolved oxygen was (5.79 (0.28) mg/L, and the pH was 7.6. The purification effect of the pollutants was as follows: the daily CODMn effluent concentration was (3.7 (0.8) mg/L, and the average removal rate was (70.54 (7.8))%; the phosphate concentration effluent concentration was (0.03 (0.01) mg/L, and the average removal rate was (93.34 (1.07)). The average total phosphorus concentration was (0.06 (0.01) mg/L, and the average removal rate of ammonia nitrogen was (91.56) respectively. The highest removal rate was 85.36%. The effluent concentration of total nitrogen was finally stabilized at 1.07 mg/L and the average removal rate was (47.24+4.33)%. Among them, CODMn met the first-class standards of (SC/T 9103-2007); pH and ammonia nitrogen met the (GB 11607-89) and < Mariculture Water Discharge Requirements > (SC/T 9103-2007) I. (2) In order to explore the purification effect of constructed wetland-biofilter combined process on pollutants in recirculating aquaculture, a composite constructed wetland system was constructed. The system was composed of aquaculture pond, biofilter, water storage pond, constructed wetland and sedimentation pond in series. The area and volume of the constructed wetland and biofilter were 1.30 m2 and 910.00 L, respectively. Coral stone, sand, biochemical filter balls and explosive cotton were used as fillers in the constructed wetland and biofilter respectively. The effluent CODMn was (3.2 (+ 0.8) mg/L; phosphate was (0.08 (+ 0.01) mg/L; phosphate was (0.08 (+ 0.01) mg/L; TP was (0.10 (+ 0.01) mg/L; daily effluent CODMn was (5.3 (+ 0.7) mg/L; phosphate was (0.05 (+) 0.01) mg/L; phosphate was (3.2.2 (+) mg/L; phosphate was (0.2.08 (+) 0.08 (+0.01) mg/L; TP was (0.04 (+0.02) mg/L; fresh water and sea water were (5.3.3 (+) 5.3 (+0./ L and (4.62+0.63) mg/L.pH, CODMn, P, TP, TN all met the discharge requirements of freshwater pond culture water (SC/T 9101-2007) and the discharge requirements of seawater culture water (SC/T 9103-2007); ammonia nitrogen met the fishery water quality standard (GB 11607-89). Composite constructed wetland system had low spatial utilization rate, low effective area and effective volume, accounting for 43.85% and 36.92% respectively. (3) In order to solve the problems existing in the operation of the composite constructed wetland water purification system, an integrated constructed wetland system was designed and constructed. The treatment unit was miniaturized, and the connecting pipes were directly connected and omitted. The results show that the two systems have poor purification capacity for pollutants during the experiment, and the concentration of each pollutant fluctuates widely. The daily effluent CODMn of the system 1 is (6.2%). The average concentration of NH4 + - N was (2.36 + 1.04) mg/L, TP was (0.08 +0.02) mg/L, TP was (0.08 +0.02) mg/L, CODMn was (4.6 +0.8) mg/L, phosphate was (0.03 +0.02) mg/L, phosphate was (0.03 +0.02 mg/L, TP was (0.05 +0.02) mg/L. The average concentration of NH4 + - N was (2.36 +1.04) mg/L, the average concentration was (7.34 +2.50 mg/L.50) mg/L.2. The average concentration of NH4 + - N was (7.34 +2.50 mg/L.50) mg/L.2.96 mg/L, TN average concentration was (7. 29 + 1.79) mg/L.pH, P and CODMn conformed to < marine culture water discharge requirements > (SC/T 9103-2007), ammonia nitrogen did not meet the requirements.
【学位授予单位】：上海海洋大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X52;X703

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