【作者】 尹月卿；

【导师】 王孝红；

【作者基本信息】 济南大学 ， 控制理论与控制工程， 2010， 硕士

【摘要】 加气砼的生产过程包括配料粉磨、制浆、浇注和蒸压养护四个环节,各环节紧密联系,相互影响,任一环节出现问题都会影响整个生产过程及成品性能。其中配料粉磨和制浆浇注都是关键环节,直接影响产品质量和合格率,所以很有必要改进这两个环节的生产过程自动化程度,对其进行优化控制,以提高产品质量和原材料利用率,同时实现降低能耗,减少环境二次污染。配料过程中计量的准确度是加气砼生产过程控制的难点之一。本文针对配料工段目前普遍存在计量不准确,物料配比不能满足要求的问题,并结合该工段的工艺特点,提出一种采用双闭环比值控制系统来实现石灰和石膏两种物料的配比,并用模糊控制算法对PID参数进行整定,实现PID参数的在线调整。模糊控制器采用双输入三输出型式。该模糊控制算法通过找出PID控制器的三个参数Kp、Ki、Kd与误差e和误差变化率ec之间的模糊关系,并在系统运行过程中不断检测e和ec,根据检测结果制定相应的模糊规则进行调整,来满足不同偏差和偏差变化率对三个参数的不同要求,使其符合控制对象的变化。使用该模糊PID控制方法对PID参数进行整定后,系统在响应速度、抑制超调等方面都要优于常规PID。试验结果表明,该系统能够适时准确地调整PID参数,从而调整原料配比,提高胶结料质量。生产加气砼的主要原料粉煤灰是燃煤火力发电厂的废弃排放物,所以加气砼生产是一种废物利用的循环经济。然而,由于加气砼生产所需原料煤粉灰、散装水泥、石膏粉和石灰等多为粉状物,这些物料在生产过程中的处理量相当大,运输环节多,故而会向大气排放粉尘、烟尘和颗粒状污染物,这样虽然达到了对电厂排放物粉煤灰废物利用的目的,却又会对环境形成二次污染。二次污染物主要来源是物料破碎、原料提升、粉磨以及传送带传送物料等工段产生的粉尘类物质污染。本文针对加气砼生产性粉尘对环境二次污染的问题,提出一套新型粉煤灰加气砼清洁生产方案,并建立了清洁生产模型,该方案能提高原材料利用率并能实现清洁生产的目的。该清洁生产方案也适用于水泥行业以及其它粉尘性污染行业的清洁生产。本文结合内蒙某加气砼厂DCS控制系统的实际使用情况,将模糊PID控制算法通过OPC接口与集散控制系统进行数据通讯。强调并采用了模块化结构,增强了算法的通用性和可移植性,降低了企业成本。本课题提出的控制方案对提高产品合格率,提高自动化生产水平和设备利用率,降低能耗,减少环境二次污染,实现资源综合利用和提高生产效率有良好的控制效果。更多还原

【Abstract】 The production of aerated concrete batching process includes four links ,material proportioning grinding, pulping, pouring and autoclaved conservation. All these sectors link cosely and influence each other . Any problems in these links will affect the production process and the performance of the the final product.Especially the grinding and pulping processes are the key links in the whole production process which directly impact on the product quality and the pass rate of the final product. Therefore it is very necessary to improve the process automation degree and optimal the control process for these two links .By doing these things ,we can improve the product quality and the material utilization ratio,and realize reducing the energy consumption and decreasing the secondary environmental pollution.The accurate measment of the material proportioning process is one of the difficult task in aerated concrete production process.In this paper ,we aim at commonly existing problem ,the inaccurate measurement and the ratio of materials can not meet the requirements in aerated concrete ingredient process, combined with its technology characteristics, proposed a double closed-loop control system to achieve the ratio of the two kinds of materials :lime and gypsum .Using the control method of fuzzy logic control to tune the PID parameters and achieving on-line tuning PID parameters in the ingredient mixing process. The fuzzy logic controller adopts double inputs and three outputs patterns. This algorithm formulate the fuzzy adjust rules by identifying the fuzzy relationship between the three parameters, Kp, Ki, Kd and its’error e and error change rate ec to meet the different quirements of error e and error change rate ec rate .Letting the controller system to satisefied the changed control object . By using this mean, the system’s responsing speed and the ability of reducing overshot is improved greatly than the conventional PID .Testing result show that the system can adjust the PID parameters online accurately and timely .Thus can adjust the material proportion and improve the cementing material quality.The main material of Aerated Concrete is the abandoned emissions of the coal-fired power plant . Therefore, the production of aerated concrete is a kind of recycling economy by using the waste emissions .However , as the raw materials needed for the production of aerated concrete are mostly power materials ,such as coal ash, bulk cement, gypsum powder and lime powder, etc. The handling amout of these materials are largely in the production process .And also there are so many transport links in the product process .So the process will emission the power dust into the atmosphere . Although it can realize taking use of the fly ash ,the emissions of power plant and achieve recycling purpose, it resulted the secondary pollution to the environment .The resoures of the second pollution come from the power dust of the material crushing,material lifting ,grinding and material transporting by belt ,and so on . This paper in view of the problem of the second pollution bring by the product power of Aerated Concrete ,proposed a new type of cleaner production program whick suits for the fly ash aerated concrete .And build the cleaner product model . The scheme can improve the utilization of raw materials and to achieve the purpose of clean production . The cleaner production scheme also applies to the clean production of the cement industry and other sectors of power dust pollutionThis paper combined the field application control system of DCS in an aerated concrete factory in Neimeng , the algorithm of fuzzy PID controller communicates with the DCS control system by the OPC interface. This project emphasized and actualized the modularization, and enhanced the universality transplantation while reduced the cost of the enterprises.The scheme provided in this paper can improve the product qualified rate, improve the automation level of production and equipment utilization, reduce energy consumption , reduce environmental secondary pollution. Achieving comprehensive utilization of resources and improve production efficiency.更多还原