【作者】 陈荣；

【导师】 王晓昌；

【作者基本信息】 西安建筑科技大学 ， 市政工程， 2011， 博士

【摘要】 本论文为国家自然科学基金重点项目“城市污水生态回用及水环境质量保障”和国家科技重大水专项课题“缺水城市雨污水再生处理和不同途径用水的关键技术研究与工程示范”的专题研究内容。论文针对全球城市化进程引发的城市水资源短缺和水环境污染问题,从“污水是重要水源”出发,以可持续城市水环境系统建设为最终目标,开展了城市污水再生利用系统的构建理论与方法研究。论文从解决城市缺水和水环境污染的主要途径入手,分析了城市污水再生利用在解决城市水问题中的优越性和必要性;在总结城市污水再生利用技术和系统现状的基础上,提出了城市污水再生利用系统构建的基本思路,并在此基础上建立了城市污水再生利用系统的基本框架;通过对集中式和分散式两种系统模式的系统构成、系统管理和系统建设的分析,明确了两种系统的不同作用分别体现为“量”和“面”两个方面,提出了集中式-分散式优化组合的系统模式;通过系统分析和模型建立,形成了以“潜力分析-水量平衡-物料平衡-模式优选-技术选择”为主线的城市污水再生利用系统构建典型流程,提出了传统城市水系统的改良和优化方案,建立了基于费用-效益分析方法的城市污水再生利用项目技术经济评价方法;理论成果应用于典型案例研究,形成了不同尺度、不同模式的系统构建实践体系。论文的主要工作及其成果包括以下方面:1.针对全球城市化短缺和水环境恶化的普遍问题,分析了新水源开发、城市节水和非常规水资源利用等解决途径的不同特征和实施效果,明确了城市污水再生利用在缓解城市缺水和改善水环境中的必要性和重要作用,提出了城市污水再生利用是构建水的良好循环的关键途径、解决城市缺水的主要途径和改善城市水环境质量的有效途径。2.在总结国内外城市污水再生利用技术和系统现状的基础上,提出了未来的发展趋势主要集中在新技术、新法规和新系统三个方面。突破城市污水“达标排放”的建设理念,通过连续的水量、稳定的水质、低廉的成本和灵活的方式的分析,验证了“污水是城市重要淡水资源”的连续性、稳定性、经济性和灵活性的四大显著特点和优势,提出了通过城市污水再生利用系统的构建,实现污水的再生、再利用和再循环,真正达到污水作为城市新增“第二水源”缓解城市缺水的目的。3.从城市终端用户着手,全面梳理了城市污水回用的主要途径,归纳为生态回用、农业回用、工业回用、市政回用、室内回用和其他回用6个方面。通过现有传统城市供排水系统的起源、发展和主要构成的分析,理清了该系统“单向直流、末端处理”的明显特性,总结了系统在水资源浪费、污染物排放、水体污染、水文循环、规划理念、管理方式等方面的问题和弊端。4.引入可持续水环境系统建设理念,从城市内部、城市与水体、城市与流域三个不同空间尺度总结了城市水系统可持续的标准和基本原则,明晰了城市污水再生利用系统构建对扩展城市水资源、减少城市水污染、丰富城市水系统的巨大促进作用,提出污水再生利用是城市建设和水环境建设的重要内容。形成了城市污水再生利用的系统框架,框架主要构成包括城市水系统体系、再生利用模式体系、回用途径体系、系统评价和约束体系四个方面。5.从系统构成、系统管理和系统建设三个主要方面对城市污水再生利用的集中式系统和分散式系统进行了综合研究和评价,明确了两种模式在城市污水再生利用系统中的不同作用,分别体现为“量”和“面”两个方面,即集中式系统的重点是提高污水再生率和回用规模,分散式系统的重点是扩大再生利用覆盖面;以此为基础,提出了“优水优用、水尽其用”、“点面结合、优势互补”的集中式-分散式组合优化系统的建设和管理方案。6.以城市污水的处理规模、再生率和城市用水总量、再生水使用率为参数建立了城市污水再生利用的潜力模型;建立了系统的总体水量平衡和污染物物料平衡方法及模型;建立了系统模式选择的技术经济方法和模型;提出了污水再生处理技术的选择方法、过程和标准;以此为基础,提出了城市污水再生利用系统构建的典型流程。7.提出了城市污水再生利用系统建设的最终目标是“最小排放”和“最大利用”,围绕此目标,研究了传统城市水系统的优化方案,提出了基于城市整体水系统的“水系集成规划”模式和“以用户为导向(End Use Need)”的多元化建设和管理模式。8.分析了不同污水再生利用途径的主要经济效益体现,建立了以净效益(NBV)为指标的费用-效益扩展经济评价模型;从直接效益和间接效益两方面重点对城市污水再生利用的经济效益进行了研究和建模,明确了效益的主要构成包括:自然资源效益、人力资源效益、环境效益;利用简化方式对污水再生利用的环境效益进行了量化模型的建立,为城市污水再生利用的效益分析提供了实用工具,避免了潜在效益的低估。9.理论研究成果和模型应用于城市污水再生利用的典型案例分析和评价,实施了西安市城市污水再生利用、西安思源学院污水再生利用和西安绿地世纪城住宅小区污水再生利用的系统构建,形成了不同尺度、不同系统模式的系统构建实践体系。在我国,城市污水再生利用事业正在快速发展,但污水再生利用系统的构建研究还处于起步阶段,尤其缺乏系统的理论框架和方法体系。建立符合我国国情的城市污水再生利用系统构建理论和方法体系,具有重要的理论意义和实用价值。本论文的研究成果为城市污水再生利用系统建设的决策、实施和管理提供了理论依据和参考,促进城市污水资源化的顺利推进。更多还原

【Abstract】 This dissertation is the thematic research content of the key project‘Study on Ecological Reuse of Treated Municipal Wastewater and Safeguard of Water Environmental Quality’funded by National Natural Science Foundation of China (NSFC) and the national program‘Study on the Technologies of Rain Water and Wastewater Treatment and Multi-purpose Reuse for the Arid and Water-deficient Urban Area in China’. Aiming at the urban water shortage and pollution caused by global urbanization, based on‘wastewater as important resource water’and sustainable urban water system (SUWS) construction, this paper focuses on the principal theory and methodology research on configuration of urban wastewater reuse system (UWRS). Priority and necessity of wastewater reuse as main solution to urban water shortage and pollution is identified through intensive analysis. Based on the status quo of urban wastewater reuse, the foundamental consideration of UWRS configuration is put forward and the framework model is established. Through analysis on system composition, management and construction of centralized and decentralized system, specific impact of the two typical systems on UWRS is ascertained as‘scale’and‘coverage’and optimal central-decentralized combined system is built. By system analysis and modelization, a typical process‘potential evaluation– water balance– material balance– system optimization– technology selection’for UWRS configuration is decided. Accordingly, the reformation and optimization of the conventional urban water system (CUWS) is proposed and an economic evaluation method is built for UWRS based on the contructed Cost-benefit models. Theoretical results of this paper are applied to different cases analysis, correspondingly multiscaled and multiformat UWRSs are established practically. The main results of the study are as follows:1. Aiming at the serious problem of urban water shortage and pollution, this paper analyzes the effects of the main three solutions including exploiting new source water, improving water use efficiency and using unconventional water. Priority and necessity of wastewater reuse is emphasized for dealing with urban water problems. The advantages of urban wastewater reuse is characterized as key approach to building up heathy urban water cycle, dealing with urban water shortage and improving urban water environment.2. The author summarizes research progress about technologies and systems of urban wastewater reuse and indicates the future trends will concentrated on new technologies, new regulations and new systems. Disregarding the traditional concept‘wastewater should be discharged’, wastewater is identified as urban important source water due to its continuity (continuous flow rate), stability (stable water quality), economy (low treatment cost) and flexibility (flexible reuse ways). The purpose of urban wastewater as“second souce water”for solving water shortage can be fullfiled by wastewater reclamation, reuse and recycle on the base of UWRS configuration.3. The main reuse purposes of treated wastewater are summarized and classified into ecology reuse, agriculture reuse, industry reuse, municipal reuse, indoor reuse and other reuse. By means of analysis on origin, development and components of CUWS, the typical feature of CUWS is extracted as unidirected flow and terminal treatment which leads to many shortcomings related to water waste, pollutant discharge, water deterioration, hydrologic cycle, plan concept and management methods.4. SUWS is introduced in this research to illustrate the tight relationship between UWRS and SUWS. The impact of UWRS on expanding urban water resource, reducing urban water pollution and enriching urban water system complies with the principles of SUWS which is composed of sustainability in inner-city, inter-city and city-watershed. Furthermore, UWRS plays the key role in SUWS. The framework of UWRS is concluded which comprises urban water supply and drainage system, reuse mode system, reuse purposes system, as well as constraint and assessment system.5. Analysis on system components, management and construction of centralized and decentralized system is made to specify the impact of the two typical systems on UWRS, which is ascertained as‘scale’and‘coverage’, correspondingly means the centralized system mainly contributes to wastewater reuse scale (percentage) and decentralize system to wastewater resue coverage. Based on this, an optimal central-decentralized combined system is put forward which fulfils the objectives of‘High quality for high level use and Different quality for differenct level use’and‘integrate point and sphere and complement advantages’.6. Regarding wastewater treatment scale, reclamation percentage, urban water comsuption and treated wastewater use percentage as parameters, the wastewater reuse potential model is built. Methods and models for system water quantity balance and pollutants material balance are put forword. System mode optimized methods and models are built on the base of economic analysis. Wastewater reclamation technologies selection method, process and criterion are also surveyed. Based on above, this paper puts forward a typical process of configuration of UWRS.7. The ultimate goal of UWRS configuration is cleared as‘minimized discharge’and‘maximized reuse’. Centered on this goal, reformation and optimization program for CUWS is proposed including“integrated water system plan”and multimode of system contruction and management driven by“End Use Need”.8. The author analyzes the major benefits performance and sets up the cost-benefit model taking the net benefit (NBV) as the indicator. In the model, the benfit including direct and indirect is divided into natural resource benefit, human resource benefit and environmental impact benefit. The environmental impact benefit is quantified and modelized exclusivey in this paper which provides the practical tools for UWRS’s benefits evaluation so that the potential benefits will not be underestimated.9. Theoretical results of this paper are applied to different cases analysis including system configuration of Xi’an City, Xi’an Siyuan College and Xi’an Greenland Housing District, correspondingly multi-scaled and multi-format UWRSs are established practically.Wastewater reclamation and reuse is developing rapidly in China, but the configuration of urban wastewater reuse system is still in its infancy and especially the systematic theory framework and configuration methods are absent. Therefore, it is important to develop the theoretical and methodological system of UWRS configuration in accord with the present situation of our country. The results of this study will assist the decision, application and management of UWRS and promote wastewater reclamation.更多还原