【作者】 王宝山；

【导师】 黄廷林；

【作者基本信息】 西安建筑科技大学 ， 市政工程， 2011， 博士

【摘要】 随着城市的快速发展,降雨形成的径流污染负荷不断升高,由此导致的面源污染成为自然水体的重要污染源。现阶段对降雨径流的研究主要集中于降雨洪峰过程对城市发展的影响,缺少降雨径流污染特征的研究,对降雨径流污染物的冲刷及输移规律的研究较少,缺乏用于指导雨水径流污染控制的相关理论与技术方法。论文通过引进径流产流负荷的概念,建立了雨水径流污染物冲刷模型,实现了对雨水过程径流水质的模拟,并结合概率分布模型对降雨污染负荷进行了评价。基于降雨径流量和污染输送过程,对降雨径流污染物的输移规律进行了研究,建立了降雨径流污染初期冲刷效应定量评价模型,实现了对初期冲刷效应强度的定量评价。在径流污染物输移规律和初期冲刷效应研究的基础上,提出了雨水径流污染控制参数计算公式。最后,开发了雨水径流污染生态绿地控制技术,为径流污染控制提供了一条新的途径。论文主要成果包括以下方面:（1）建立了雨水径流污染物冲刷模型以径流产流负荷替代降雨强度校正了传统的径流污染物冲刷模型,在此基础上建立了雨水径流污染物浓度模型: C（t）=M₀×(0.01+α/(1.1-exp(-H_ef/b)×R_ef^α)×exp[(-0.01×H_ef+(∫₀^t-α/(1.1-exp(-H_ef/b))×R_ef^1+αdt)]校正后的冲刷模型能够消除降雨过程和径流输送之间的时间差,提高了降雨径流污染物浓度模型的精度。雨水径流浓度模型对径流污染物浓度模拟结果与实测结果拟合性较好,冲刷模型可用于径流污染冲刷规律研究。建立的雨水径流污染物水质模型,有助于对雨水径流污染输移规律的深入研究。（2）提出了地表积累污染物的计算方法吸尘器收集的地表积累污染物不能代表实际可冲刷转移至径流中的污染物,因此在提出了地表可冲刷污染物积累量概念,在污染物冲刷模型的协同下实现了可冲刷污染积累量的计算。与吸尘器收集的全部积累污染物量相比,可冲刷污染物积累量代表了地表可被冲刷转移至雨水径流中的污染物,因此可冲刷积累量远小于吸尘器收集获得的污染物积累量。污染物可冲刷积累量可以直接应用于径流污染物冲刷模型,减小了因地表积累污染物难以定量所带来的模拟误差。（3）实现了雨水径流污染负荷的评价基于概率分布模型,建立了雨水径流污染负荷累积概率模型和平均浓度数学期望模型,模型可应用于雨水径流污染负荷状况的评价,并实现了降雨径流污染平均浓度的预测。雨水径流污染负荷模型的评价结果表明,西安市主城区年雨水径流COD负荷相当于2500万m³城市市政污水,是不可忽视的城市水环境污染源。降雨量与雨水径流污染物平均浓度显现负相关过程,随着降雨量的增加雨水径流污染物平均浓度产生下降趋势,初期降雨是雨水径流污染形成的主要时期,是城市雨水径流污染控制的最佳实施期。（4）对雨水径流污染物输送过程进行了模拟基于降雨—净雨转化模型,通过对净雨强度的恒定化处理,在坡面流的圣维南方程组基础上,实现了降雨径流量的模拟。结合雨水径流污染物冲刷模型,对汇流面雨水径流污染物输移规律进行了研究。以汇流区域污染物输移模型为基础,利用Muskingum流量方程,建立了雨水管道雨水径流污染物流量和浓度模型,模型能够对大区域（含雨水管道）雨水径流污染物输移进行模拟。雨水径流污染物的输移过程研究为雨水径流污染控制提供了技术依据。（5）建立了雨水径流初期冲刷效应定量评价模型以雨水径流量和污染物输送过程为基础,建立了雨水径流初期冲刷效应间隙函数,从而提出了雨水径流污染初期冲刷效应定量评价模型: SFF=∫₀¹[f（F）-F]dF雨水径流污染初期冲刷效应间隙函数存在峰值区域,峰值区域代表的径流深度是雨水径流污染控制的高效区,雨水径流污染物的控制以峰值前径流控制为主。评价模型实现了对雨水径流和季节性初期冲刷效应的定量评价,从而可以针对性的采取相应的污染控制措施,为雨水径流污染物的高效控制提供了理论技术依据。（6）开发了雨水径流污染生态绿地控制技术在雨水径流污染输移和初期冲刷效应研究的基础上,提出了雨水径流污染控制参数。开发了雨水径流污染物生态绿地控制技术,雨水生态绿地中设置了沉水厌氧区,创造了持续稳定的厌氧环境,促进了反硝化过程。雨水生态绿地中植物吸收只去除了积累TN的20%,但雨水生态绿地中未发生明显的TN积累,因此沉水厌氧区的设置对TN的去除发挥了重要的作用。同时,沉水厌氧区的蓄水通过毛细作用到达土壤表层供给生物生长,提高了土壤含水率,雨水生态绿地中的植物显示了更加优越的景观功能。雨水生态绿地在雨水径流污染控制的基础上,实现了雨水利用,可以广泛的应用于雨水径流污染的控制。论文通过雨水径流污染物输移规律的研究,提出了相应的污染控制方案和技术方法,从而为雨水径流污染物的控制提供了理论技术支持。更多还原

【Abstract】 The rapid urban development experienced in recent decades has led to significant changes in both the volume and quality of rainwater runoff, leading to the eventual eutrophication and the consequent wastage of the water resource. Greater emphasis was now placed on the quantity of storwater runoff, but absence of quality. The theory and technical methods were not available to guide stormwater runoff pollution control, because the wash-off and transportation of pollutants were not investigated deeply in stormwater runoff.With the introduction of the concept of runoff load, a new wash-off model was established, which could apply to simulated stormwater runoff quality, and pollution load was evaluated based on probability distribution model. The transportation regular of stormwater runoff pollution was studied with simulation of quantity and quality, which could be used to establish quantitative evaluation for the first flush effect. Then, the pollutants control parameter formula was proposed based on the transportation regular and first flush effect. In the end, stormwater ecological vegetation was built to removal of stormwater pollutants. The major achievements in this paper were expressed as following:（1） Establishment the wash-off model of stormwater runoffThe runoff load was adopted to substitute rainfall intensity, and stormwater runoff quality model was presented with traditional wash-off model calibrated. The quality model was: C（t）=M₀×(0.01+α/(1.1-exp(-H_ef/b)×R_ef^α)×exp[(-0.01×H_ef+(∫₀^t-α/(1.1-exp(-H_ef/b))×R_ef^1+αdt)]The new model eliminated the time difference between rainfall and pollutants wash-off, increased the accuracy of simulation. The simulation results of total suspend solid fitted to experiment well, which could be used to investigate the runoff pollution transportation regular. The quality existed direct function relationship with runoff quantity in wash-off model, which was beneficial to study runoff pollution transportation deeply.（2） Presentment the new computational model to pollutants build-upThe vacuuming method usually used to sediment collection, they were not effective for evaluation of the wash-off pollutants because stormwater only removed part of cumulative pollutants. Based on wash-off pollutants in stormwater runoff, the conception of available cumulative wash-off pollutants was presented, and the computational model was established with the wash-off model.It was found that available cumulative wash-off pollutants were far below of vacuuming collection, largely because only a small fraction of pollutants was mobilized to runoff. Available cumulative wash-off pollutants mainly focus on the wash-off pollutants which could applied to wash-off model without calibration. The runoff quality model error would be reduced greatly with using available cumulative wash-off pollutants。（3） Implement the evaluation of runoff pollutant loadsWith pollutant buildup and washoff functions, the cumulative distribution functions （CDFs） of pollutant loads and the expected value of pollutant event mean concentrations （EMCs） were derived. The model can be used to evaluate the stormwater pollutant loads and calculate the pollutant event mean concentrations. The evaluation for pollutant loads indicated that the COD load of Xi’an city was equivalent to the load of 25 million m³ of municipal wastewater, which showed that the pollutants in runoff were major source to urban water environment. The rainfall affected on pollutant event mean concentrations, the EMCs of runoff was negative correlation to rainfall. The concentration of pollutants in initial period was substantially higher than later, so it was effective step to control the runoff in initial period.（4） Simulation to runoff pollutants transportationThe runoff flow was simulated with integrating the rainfall-net rainfall transformation and Overland flow of the Saint-Venant equations. Combined by pollutants wash-off, the stormwater runoff pollutants transportation regular was investigated in different catchments. Then, based on Muskingum flow equation, storm sewer runoff quantity and quality model was presented. The simulation of pollutants transportation could be developed to the first flush effect and runoff pollutants control.（5） Establishment quantitative evaluation model to the first flush effect Integrating runoff quantity and quality, the difference function was created by the difference between the dimensionless cumulative pollutants and the dimensionless cumulative runoff volume. Based the difference function, the strength of first flush was presented: SFF=∫₀¹[f（F）-F]dFThe first flush difference function dominated in positive, and there was peak area, which was effective area to control runoff pollutants, the runoff pollutants should be controlled before peak time. The model implemented the quantitative evaluation to the first flush of stormwater runoff and seasonal flush. The quantitative evaluation model to the first flush effect could help to investigate for runoff pollution transportation and be useful development of best management practice.（6） Development stormwater ecological vegetation technologyWith modification of standard bioretention by adding a submerged anoxic zone, stormwater ecological vegetation （SWEV） provided excellent nutrient removal from rainwater. Denitrification in submerged anoxic zone may play an important role in the nutrition balance. Microbes provided the denitrification process to promote the conversion of accumulated nitrogen species to nitrogen gas, with the off-gas release of nitrogen to the atmosphere. Plant harvesting removed only 20% of capture nitrogen, but nitrogen was not found accumulation obviously in SWEV, demonstrating that denitrification in submerged anoxic zone was important to nitrogen removal. In SWEV, the stormater was harvested in the submerged zone and utilized by capillary action, which improved the plant growth. Not only can SWEV provide efficient pollutant removal, but it can also supply an additional water resource. SWEV can be designed for widespread implementation of runoff pollution control.The runoff pollutants control programs and techniques were presented with the transportation of runoff pollution investigated, which would be helpful development of best management practice for stormwater runoff pollutants.更多还原