Study On Optimization Method For Water Quality And Quantity Joint Operation In Urban Raw Water System And Its Application

Water conservancy constitutes a basic condition, basic support and an important safeguard for economic and social development. To speed up the reform of water resource development becomes an important national strategy of the current period. To ensure drinking water safety in urban and rural areas in a comprehensive manner is an important target of the "12th Five-Year Plan". Urban raw water system is the main water source of city life, production, and environment, thus a healthy and sustainable development of raw water system becomes a necessary condition for building a moderately prosperous society. Scientific scheduling and management of raw water system cannot live without recognizing the fact that water resources has dual unified properties of "water quality" and "water quantity". The study on optimal scheduling of urban raw water system shall start from the joint scheduling of the water quality and quantity to explore the interactive law between the water quality, water quantity and scheduling objectives.With urban raw water system as research subject, this dissertation focuses on the protection of urban drinking water safety, conducts analysis of raw water system structure characteristics, and explores the raw water system water quality simulation model and water quantity scheduling simulation model. Based on single-mode of traditional water quantity scheduling model, water quality and water quantity control-coupling model is built providing proposal on an evaluation and decision-making methods for the dynamic process of water quality in reservoir group so as to develop decision-supporting system for the joint optimization and scheduling of water quality and quantity in urban raw water system by making use of existing information collection platforms such as water quality testing system and reservoir scheduling information management system. The scheduling system, water pollution sources monitoring system and water plant process control system set up in this pater together constitute the urban water source security system which can improve water supply security, effectively alleviate pressure of emergency treatment to sudden water source pollutionin water treatment plant, create safe drinking water condition for urban residents, and thus promote economic development and social stability. The main achievements of this dissertation are as follows:(1) Establishment of water quality model of urban raw water system.In accordance with the structural characteristics of the raw water system, the raw water system water quality model was established based on the basic equation of water quality migration and the biochemical reaction principle of water quality components. Noted that water quality model of raw water system has characteristics of multiple-input-multiple-output and associated water quality components, the paper proposes a method for improving the water quality model; combines PSO and gradient method to carry out multi-parameter optimization to the model; compares simulation result with measured data to validate reasonability of the model.(2) Establishment of water quantity optimal scheduling model and computer simulation model. Based on analysis of water demand variation of water plants in Shenzhen raw water system, the paper proposes a simple method for forecasting water demand in water plants and estimating rainwater resources, establishes an optimal scheduling model for the raw water system based on the supply-demand balance dynamic simulation technology, and solves the model with large system decomposition coordination principle. By making use of graph theory, extension analysis, data structures and computer object-oriented technology, the paper makes a study on computer dynamic storage technology of complex network structure of raw water system is made, designs and develops a computer simulation model of raw water system based on object-oriented technology.(3) Proposal of an evaluation and decision-making method for reservoir group multi-component water quality and quantity joint scheduling program.By analyzing characteristics of reservoir group multi-component water quality dynamic process evaluation, a three-dimensional information space structure description method is proposed for scheduling scheme; based on single factor water quality evaluation method and composite index evaluation method, the papers proposes asingle factor pollution index (SFPI); establishes evaluation index system with the SFPI and reservoir storage as basic indicators, and proposesthe evaluation and decision-making method for reservoir group multi-component water quality dynamic process. This method is then used to make evaluation and decision-making on the joint scheduling program of water quality and quantity of the raw water system. As the results of the evaluation is one of the optimal scheduling goals of the raw water system water quality and quantity control coupling model referred to in chapter six, it provides new ideas for decision-making of water quality and quantity joint scheduling.(4) Establishment of water quality and quantity control coupling model of raw water system.A basic model of water quality-quantity feedback controlis constructed by applying decentralized control principle of the large scale system theory and qualitative control method and using single reservoir as basic control unit; qualitative reasoning and qualitative mathematical method are used to predict the law of interaction in-between water quality component of different reservoir group; decision tree analysis method is employed to analyze water quality and quantity regulation strategies, generate a regulation strategy set in the form of decision tree form, and implant the decision tree into strategy analyzer to establish water quality and quantity control coupling model; the paper conducts an analysis on the contradiction between water quantity optimal scheduling and water quality simulation as their solve order in cyberspace is different; based on mixed depth-first and breadth-first traversal algorithm of graph, the paper discusses the method for solving the raw water system quality and quantity control coupling model in both dimensions of time and space; rationality of the model as well as water quality control effect is verified with case analysis.(5) Design and development of Shenzhen municipal water source scheduling and management system.With analysis of water resource management mechanisms and water-source-scheduling business in Shenzhen city, determine the main demands for water-source-scheduling in Shenzhen city; in accordance with the existing information collection platform, design architecture of the system; and introduce the main functions, deployment and application of the system which provides the main technical support for improving technical level of urban water resource scheduling and management in China.