北方季节性河流生态反应器水质模型研究
发布时间：2018-08-29 17:09
【摘要】：中国北方地区人口众多,工农业发达,生产生活需水量大,但降水量不足且随季节分配不均,枯水期缺水现象严重,人均水资源占有量极度匮乏。上世纪90年代以来,由于社会经济的迅速发展和城市化进程的加快,北方地区污染物排放量增加,导致河流生态系统被破坏,自净能力减弱,造成水质的严重污染。迫切需要采取工程手段,提升中国北方河流的自净能力,实现河流水质的可持续性改善。河流水体是一个复杂的自然生态系统,其自净过程受微生物学、化学、大气物理学、流体力学等多种因素控制,各因素之间相互作用、相互制约、相互影响,如果直接进行试验来研究它们的自净能力,需要投入较多人力、物力、财力,而通过建立基于反应器原理的水质模型,则可以定量或者定性描述水体中污染物降解、迁移和转化规律,预测水质状态,提供管理、监测依据,这就大大节约成本。本文在国内外地表水水质模型的研究工作的基础上,对比国内外几种常用水质模型的优缺点,结合中国北方季节性河流的特点和现状,筛选美国环境保护署(EPA)开发的水质分析模拟模型WASP,基于反应器原理,建立用于模拟、预测北方季节性河流的数学模型,分别用原始的WASP模型和改进后的WASP模型评价河道曝气、人工湿地下污染物去除效果的影响机制,为实现河流生态反应器的水环境量化、优化、决策和控制打下基础。曝气充氧是修复受污染河道的重要技术,数学模型是预测、评估环境污染状况的重要方法。本研究首次应用WASP水质模型评价不同时段河道曝气对河流水质的提升作用。初期模型验证结果表明：基于WASP水质模型建立的河流生态反应器水质模型拟合结果与实际监测结果基本吻合,可为水污染治理工程提供参考依据。在此基础上,对不同曝气条件进行模拟分析,结果表明：河道曝气能够有效降低河水中的化学需氧量(COD)和氨氮(NH3-N)浓度,改善水质；随着曝气河段内溶解氧(DO)水平的提升,水质虽不断改善,但改善幅度逐渐减小；全年不同月份曝气效果差异显著,5-9月曝气效果较好。结合经济投入和环境效益,最终确定夏季提升DO水平达到4mg/L为河道曝气最优条件。表流人工湿地造价低、运行管理方便,具有生态效益和景观价值,能够取得较好的废水处理效果。目前对于表流湿地的研究缺乏基于过程的模型指导工具。本文结合湿地的特点,修正WASP模型,进而体现湿地系统的植物对于水质和水动力条件的影响。选取中国北方的一处典型的河道表流人工湿地,验证河流生态反应器模型对于河道表流湿地模拟研究的适用性,提供了一种定量指导人工湿地植物种植的方法。模拟结果表明：河道表流湿地在全年各个季节内均能对上游来水中的污染物有着明显的去除效果,但是在冬季气温较低时,氨氮的去除受到较大的影响,去除效果会减弱；增加湿地植物种植密度或者种植规格更大的植物均能够有效提升湿地反应器对于NH3-N的去除效果,但对于COD的去除效果几乎没有提升。应结合经济成本、植物生长环境、控制目标等因素来综合制定人工湿地设计、管理策略。本研究把河流水体看作反应器,筛选WASP水质模型作为研究的基本工具,并对原模型进行适用范围的扩大,对河流水质进行模拟、预测、分析,验证综合模型的适用性,具有理论意义。根据中国北方河流的现状,构建了集成河道曝气或人工湿地工程技术手段的河流生态反应器水质模型,丰富地表水水质模型的表达和应用。通过假设采用工程技术手段时的不同工况,改变模型参数,预测对水质改善的影响,体现了模型研究方法的优势。为指导建设河流生态修复工程和水污染控制管理决策提供科学依据,具有应用价值。
[Abstract]:Northern China has a large population, developed industry and agriculture, and a large demand for water for production and living. However, the precipitation is insufficient and unevenly distributed with the seasons. Water shortage is serious in dry season, and the per capita water resources are extremely scarce. Since the 1990s, with the rapid development of social economy and the acceleration of urbanization, the pollutant discharge in northern China has increased. It is urgent to adopt engineering measures to enhance the self-purification capacity of rivers in northern China and achieve sustainable improvement of river water quality. Fluid mechanics and other factors control each other. The factors interact with each other, restrict each other and influence each other. If the experiment is carried out directly to study their self-purification ability, more manpower, material and financial resources are needed. By establishing water quality model based on reactor principle, the degradation and migration of pollutants in water body can be described quantitatively or qualitatively. Based on the study of surface water quality models at home and abroad, the advantages and disadvantages of several common water quality models at home and abroad are compared, and the development of EPA is screened according to the characteristics and current situation of seasonal rivers in northern China. Water quality analysis and simulation model WASP, based on the principle of reactor, establishes a mathematical model for simulating and predicting the seasonal rivers in North China. The original WASP model and the improved WASP model are used to evaluate the influencing mechanism of pollutant removal effect under aeration and constructed wetland respectively. In order to realize the quantification, optimization and decision-making of water environment in river ecological reactor, the water quality analysis and simulation model are carried out. Aeration is an important technology for remediation of polluted rivers. Mathematical model is an important method for predicting and evaluating environmental pollution. In this study, WASP water quality model was used for the first time to evaluate the effect of aeration on river water quality in different periods. The fitting results of the water quality model of the river ecological reactor are basically consistent with the actual monitoring results, which can provide reference for water pollution control projects. With the increase of dissolved oxygen (DO) level in the aerated reach, the water quality has been improved continuously, but the improvement range has been gradually reduced; the difference of aeration effect in different months of the year is significant, and the aeration effect is better from May to September. At present, there is no process-based model to guide the study of surface flow wetlands. In this paper, the WASP model is revised according to the characteristics of wetlands to reflect the impact of wetland plants on water quality and hydrodynamic conditions. A typical river surface flow constructed wetland in the north of China was used to verify the applicability of the river ecological reactor model to simulate the river surface flow wetland and to provide a quantitative method for guiding plant cultivation in the constructed wetland. The removal efficiency of NH3-N by wetland reactor can be improved by increasing the density of wetland plants or planting plants with larger specifications, but the removal efficiency of COD is almost not improved. Economic cost, plant growth environment, control objectives and other factors to formulate a comprehensive design of constructed wetlands, management strategies. This study regards river water as a reactor, screening WASP water quality model as a basic tool for research, and expands the scope of application of the original model to simulate, predict, analyze and verify the applicability of the integrated model. According to the present situation of rivers in northern China, a river ecological reactor water quality model integrated with river aeration or constructed wetland engineering technology is constructed to enrich the expression and application of surface water quality model. The influence reflects the advantages of the model research method, and provides scientific basis for guiding the construction of river ecological restoration project and water pollution control and management decision-making.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X522
本文编号：2211863
[Abstract]:Northern China has a large population, developed industry and agriculture, and a large demand for water for production and living. However, the precipitation is insufficient and unevenly distributed with the seasons. Water shortage is serious in dry season, and the per capita water resources are extremely scarce. Since the 1990s, with the rapid development of social economy and the acceleration of urbanization, the pollutant discharge in northern China has increased. It is urgent to adopt engineering measures to enhance the self-purification capacity of rivers in northern China and achieve sustainable improvement of river water quality. Fluid mechanics and other factors control each other. The factors interact with each other, restrict each other and influence each other. If the experiment is carried out directly to study their self-purification ability, more manpower, material and financial resources are needed. By establishing water quality model based on reactor principle, the degradation and migration of pollutants in water body can be described quantitatively or qualitatively. Based on the study of surface water quality models at home and abroad, the advantages and disadvantages of several common water quality models at home and abroad are compared, and the development of EPA is screened according to the characteristics and current situation of seasonal rivers in northern China. Water quality analysis and simulation model WASP, based on the principle of reactor, establishes a mathematical model for simulating and predicting the seasonal rivers in North China. The original WASP model and the improved WASP model are used to evaluate the influencing mechanism of pollutant removal effect under aeration and constructed wetland respectively. In order to realize the quantification, optimization and decision-making of water environment in river ecological reactor, the water quality analysis and simulation model are carried out. Aeration is an important technology for remediation of polluted rivers. Mathematical model is an important method for predicting and evaluating environmental pollution. In this study, WASP water quality model was used for the first time to evaluate the effect of aeration on river water quality in different periods. The fitting results of the water quality model of the river ecological reactor are basically consistent with the actual monitoring results, which can provide reference for water pollution control projects. With the increase of dissolved oxygen (DO) level in the aerated reach, the water quality has been improved continuously, but the improvement range has been gradually reduced; the difference of aeration effect in different months of the year is significant, and the aeration effect is better from May to September. At present, there is no process-based model to guide the study of surface flow wetlands. In this paper, the WASP model is revised according to the characteristics of wetlands to reflect the impact of wetland plants on water quality and hydrodynamic conditions. A typical river surface flow constructed wetland in the north of China was used to verify the applicability of the river ecological reactor model to simulate the river surface flow wetland and to provide a quantitative method for guiding plant cultivation in the constructed wetland. The removal efficiency of NH3-N by wetland reactor can be improved by increasing the density of wetland plants or planting plants with larger specifications, but the removal efficiency of COD is almost not improved. Economic cost, plant growth environment, control objectives and other factors to formulate a comprehensive design of constructed wetlands, management strategies. This study regards river water as a reactor, screening WASP water quality model as a basic tool for research, and expands the scope of application of the original model to simulate, predict, analyze and verify the applicability of the integrated model. According to the present situation of rivers in northern China, a river ecological reactor water quality model integrated with river aeration or constructed wetland engineering technology is constructed to enrich the expression and application of surface water quality model. The influence reflects the advantages of the model research method, and provides scientific basis for guiding the construction of river ecological restoration project and water pollution control and management decision-making.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X522
【参考文献】
相关期刊论文 前1条
1 杨家宽,肖波,刘年丰,章北平,李进军,何归丽;WASP6水质模型应用于汉江襄樊段水质模拟研究[J];水资源保护;2005年04期
，本文编号：2211863
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