补水及面源负荷对伏牛溪水质影响的数值模拟

发布时间：2018-04-26 17:40

本文选题：数值模拟 + 生态补水　；参考：《重庆大学》2015年硕士论文

【摘要】：重庆典型重污染河流伏牛溪在实施了一系列整治工程后,仍然存在着面源污染严重、河流水生态系统尚未完全修复、景观功能基本丧失的问题。对伏牛溪补充达到地表Ⅴ类水环境标准的水源、控制面源污染成为伏牛溪进一步治理的措施。如何在补水时更好地改善河源水库水质,以及如何根据伏牛溪水环境容量,确定伏牛溪流域面源污染负荷的削减量,从而指导伏牛溪流域今后的规划建设,是现阶段伏牛溪综合整治工程迫切需要解决的问题。为此,研究采用数值模拟的方法,对伏牛溪补水工程实施时,不同补水点位置和数量设置方式对补水效果的影响进行数值模拟,从提高水库水质改善效果的角度,确定了补水点的位置和数量;同时,模拟预测了面源污染负荷对河道水质的影响,并通过伏牛溪河道水环境容量计算,确定了伏牛溪流域的面源负荷削减目标。研究为伏牛溪河源水库补水方案的实施以及流域的合理的规划建设提供了依据。研究得出的主要结果及结论如下:①口袋沟水库补水点设置位置和数量的数值模拟研究结果表明:1)如按单一补水点进行补水,连续补水14天,水库约43000m2水面面积达到地表Ⅴ类水质标准,占水库总面积的78.2%,但泄水口左侧面积约9000 m2库湾处区域水质无法达标。因此采用单一补水点进行补水,滞流区水质难以得到改善;2)如按双补水点进行补水,且两个补水点分别分配水量12000m3/d和3000m3/d条件下,连续补水14天,水库约49500m2水面面积达到地表Ⅴ类水质标准,占水库总面积的90.1%。水库中虽有两处滞流区的水质难以改善,但总面积仅为约3000m2,占水库总面积的5.5%。采用双补水点进行补水,水质改善效果优于单一补水点,但会增加约500m的管道工程投资;3)如按三补水点进行补水,水库中水质开始变化时间缩短,连续补水14天,水库约42000m2水面面积达到地表Ⅴ类水质标准,占水库总面积的76.4%。由于补水点的分散,补水点水量的减小降低了水动力的对流扩散作用,以及水动力场相互抵消的原因,补水点对岸约8000m2的水质很难改善,占水库总表面面积的14.5%。4)从降低补水管道工程费用角度考虑,设置单一补水点是较优的设置方式;从水质改善的角度考虑,设置双补水点,可获得更好的水质改善效果。②伏牛溪流域面源污染负荷对河道水质影响的数值模拟研究结果表明:1)当雨量达到中雨强度时,上、中游河道CODMn、TN不能达到地表V类水质标准,全河段TP、NH3-N可以达标;当雨量达到大雨强度时,全河段TP、CODMn、TN不能达标,NH3-N可以达标;当雨量达到暴雨及大暴雨强度时,全河段CODMn、TN、TP均不能达标,上游河段NH3-N不能达标,中、下游河段NH3-N可以达标。伏牛溪河道中CODMn、TN组分受面源污染负荷影响较大。2)COD、TN是伏牛溪流域面源污染负荷中需要重点治理的污染物。为满足水环境容量要求,伏牛溪河道COD、TN污染负荷分别需要削减41.4%和41.7%,TP、NH3-N污染负荷分别需要削减25.3%和19.3%,其中,上游河段COD、TN削减量分别占总削减量的69%和66%;TP、NH3-N污染负荷削减量则全部来自上游河段,因此,上游河段是伏牛溪河道控制面源污染需要重点治理的区域。
[Abstract]:After a series of renovation projects have been carried out in the typical heavy polluted river in Chongqing, there is still a serious problem of surface source pollution, the river water ecosystem has not been completely restored and the landscape function is basically lost. How to improve the water quality of the Heyuan reservoir and how to determine the reduction of the pollution load in the volt river basin according to the water environment capacity of volt ox Creek and guide the future planning and construction of the volioxi river basin is an urgent problem to be solved in the current stage of the comprehensive renovation project of volt ox Creek. Methods the influence of the location and quantity of different water filling points on the effect of water supplement was simulated. The position and quantity of the water filling point were determined from the angle of improving the water quality of the reservoir. At the same time, the influence of the negative charge on the water quality of the river was simulated and predicted. The calculation of environmental capacity determines the target of the reduction of the source load in the volioxi River Basin. The research provides the basis for the implementation of the water supplement scheme and the rational planning and construction of the Heyuan reservoir in volioxixi. The main results and conclusions are as follows: (1) the numerical simulation results of the location and quantity of the setting and quantity of the water supplement point in the pocket Reservoir show that: 1) the water surface area of about 43000M2 of the reservoir reaches the grade V water quality standard, accounting for 78.2% of the total area of the reservoir, which is about 78.2% of the total area of the reservoir, but the water quality on the left side of the outlet is about 9000 m2 in the area of the reservoir Bay. Therefore, the water quality of the stagnant area is difficult to be improved by using a single water filling point. 2) such as double supplement water. Under the conditions of 12000m3/d and 3000m3/d, the water surface area of the reservoir is 14 days, and the water surface area of the reservoir has reached the grade V water quality standard. The water quality of two stagnant areas in the 90.1%. reservoir, which accounts for the total area of the reservoir, is difficult to improve, but the total area is only about 3000m2, accounting for 5.5%. of the total area of the reservoir. The water quality improvement effect is better than the single water filling point, but the water quality improvement effect is better than the single water filling point, but it will increase the investment of the pipeline project about 500m; 3) the water quality in the reservoir is shortened and the water is continuously replenishing for 14 days. The water surface area of the reservoir reaches to the surface grade V water quality standard, which accounts for the 76.4%. of the total area of the reservoir, which is due to the water replenishment point. The dispersion of the water and the decrease of the water content of the filling point reduce the convection and diffusion of the hydrodynamic force, and the cause of the counteraction of the hydrodynamic field. The water quality of the 8000m2 is difficult to improve, and the 14.5%.4 of the total surface area of the reservoir is a better way to set up a single water supply point from the angle of reducing the cost of the water supply pipeline. The results of numerical simulation study on the effect of surface pollution load on river water quality in volt ox Creek Basin show that: 1) when rainfall reaches the intensity of medium rain, the CODMn, TN in the middle reaches of the river can not reach the V water quality standard on the surface of the river, the whole river section is TP, and the NH3-N can reach the standard; when the rainfall is up to the standard, when the rainfall is available, the rainfall is up to the standard. When the intensity of heavy rain is reached, the whole river section TP, CODMn, TN can not reach the standard, and NH3-N can reach the standard. When the rainfall reaches the storm and heavy rain intensity, all the CODMn, TN, TP in the whole river can not reach the standard, the upstream section NH3-N can not reach the standard, and the lower reaches of the river reaches the standard. The CODMn of the volt cattle stream, the TN component is influenced by the greater.2). In order to meet the requirements of water environmental capacity, the COD and TN pollution loads in volt river channel should be reduced by 41.4% and 41.7%, TP, and NH3-N, respectively, by 25.3% and 19.3%, respectively. The COD and TN reductions in the upper reaches of the river are 69% and 66% of the total reduction, TP, NH3-N pollution load, respectively. The reduction is all from the upper reaches. Therefore, the upstream reaches are the key areas to control the non-point source pollution of the funixi river.

【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X52

【相似文献】