自来水混凝投药过程建模与模糊控制研究

发布时间：2018-06-13 00:22

本文选题：水处理 + 混凝投药　；参考：《昆明理工大学》2014年硕士论文

【摘要】：自来水是城市生活的命脉,伴随着经济的迅猛发展,城镇居民对自来水水质的要求也日益提高。作为自来水的生产部门,自来水厂提高净水工艺,控制出厂水质浊度指标,使居民用上放心水是保障人民身体健康的前提。混凝投药是地表水处理工艺流程中的重要环节,也是复杂的物理化学反应过程。对于不断变化的源水质量参数,自来水厂应合理控制混凝沉淀过程的投药量,实现智能化投药,以达到自来水生产低成本、低浊度、高质量的目标。自来水混凝投药系统是一个大延时、强耦合、干扰因素多的非线性系统。本文以云南省昆明市某自来水厂的混凝投药系统作为研究背景,分析了自来水厂地表水处理工艺流程及各项参数指标,根据水厂大量生产数据,分析源水流量、源水浊度、液体聚铝投药量等影响水处理的因素与混凝投药系统出水浊度之间的关系,采用系统辨识方法对源水浊度进行短期预报,并建立了混凝投药过程的控制模型和扰动模型。依据水厂飞升实验数据,采用最小二乘法建立了沉淀过程传递函数模型,并将智能控制的重要分支——模糊控制技术引入对变频加药泵的控制中。分析了传统PID控制算法的缺点,设计完成模糊自整定PID控制器,为自来水厂严格控制出厂水浊度提供了有效的方法。对于自来水混凝投药系统存在的问题,使用Matlab实现系统建模,并完成基于西门子PLC和WinCC组态软件的监控系统设计方案。通过对自来水厂混凝投药系统的分析以及对先进控制策略的研究,探索适于昆明地区的水处理混凝投药控制方案。最佳投药控制的实现减低了液体聚铝的投放量,降低了生产成本,对提高水质起到较大的促进作用。
[Abstract]:Tap water is the lifeblood of city life. With the rapid development of economy, urban residents' demand for tap water quality is also increasing day by day. As the production department of tap water, the waterworks improve the process of water purification, control the turbidity index of the water quality of the factory, and make the residents use rest assured water is the premise to ensure the health of the people. Coagulant dosing is an important part of surface water treatment process and a complex physicochemical reaction process. In order to achieve the goal of low cost, low turbidity and high quality of tap water production, the water plant should control the dosage of coagulant and precipitate process rationally and realize intelligent dosing for the changing quality parameters of source water. The coagulant dosing system of tap water is a nonlinear system with long time delay, strong coupling and many disturbance factors. Based on the coagulation and dosing system of a waterworks in Kunming City, Yunnan Province, this paper analyzes the surface water treatment process and various parameters of the waterworks. According to the mass production data of the waterworks, the flow rate and turbidity of the source water are analyzed. The relationship between the factors affecting water treatment and the turbidity of the effluent of coagulant dosing system is discussed. The short-term prediction of turbidity of source water is carried out by system identification method, and the control model and disturbance model of coagulant dosing process are established. The transfer function model of precipitation process is established by using the least-square method based on the experimental data of the rising of water plant, and the fuzzy control technology, an important branch of intelligent control, is introduced into the control of the variable frequency feed pump. The shortcomings of the traditional pid control algorithm are analyzed, and the fuzzy self-tuning pid controller is designed and completed, which provides an effective method for the waterworks to strictly control the turbidity of the raw water. For the problems existing in the coagulant dosing system of tap water, Matlab is used to realize the modeling of the system, and the design scheme of the monitoring system based on Siemens PLC and WinCC configuration software is completed. Based on the analysis of coagulant dosing system in waterworks and the study of advanced control strategy, the control scheme of coagulant dosing for water treatment in Kunming area was explored. The realization of optimal dosing control reduces the amount of liquid polyaluminum, reduces the production cost, and promotes the improvement of water quality.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU991.2;TP273.4

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