Design And Development Of Water Supply Monitoring System For Thermal Plant Boiler

It is well known that electric power is an important basic industry, and it is important and advanced industry in development strategy of national economy. Nowadays, electric power industry of China grows rapidly, thermal plant accounts for 70 percent national power plant. Because water plays an important role in transferring the energy and cooling medium in the process of generating electricity, water treatment is very important.Chemical water workshop of power plant is the place to perform chemical water-treatment and provide eligible supply-water for boiler. It is very important for operating securely and economically of power plant that treatment equipments of supply-water for boiler could function safely and supply-water is of high quality. In China, the phenomenon is that automation of desalting system is usually low and production condition is dropped behind. Sometimes, treatment equipments of supply water for boiler are operated artificially, the quantity of acid and alkali consumptions are above standard, the economical benefits are influenced seriously. Most of the chemical instruments implement off-line sampling, and the accuracy is exceedingly low. Therefore, the quality of treated water can't be controlled steadily, and then the normal operations of boiler are affected. Once the quantity of desalting water isn't enough, the boiler will stop, and the consequence will be too bad to be imagined.This paper's project background is an actual item of domestic thermo-electric plant. Besides, the paper introduces the design and realization of a chemical water workshop supervisory control system, which is based on the configuration software iFIX.Firstly, the paper summarizes the industrial process supervisory control system and the features of the three main supervisory control systems, and analyzes the theory of demineralixation systems flow path of chemical water process system and the flow chart of equipments in different kinds, which is the base of the following research of automation of singular equipment and the whole flow path of demineralixation system. It introduces the devising methods of the straightforward- control layer in thermo-electric plant, including choosing control equipments,the choosing of PLC and configuration,the ways of program designing in the upper monitor and lower computer and etc. We use the developing software "Unity Pro" of Modicon Company to design the program of lower monitor. Because of the high request of water process system's reliability in thermo-electric plant, the system safety is assured by ways of several redundancy measures on aspect of system hardware's configuration. The chemical water workshop supervisory control system discussed in this paper has been utilized after debugging, it runs very steadily and comes up to the anticipative effect.Finally, what I have done for this paper is concluded and the work that are worthy of and needed to be done in the future is also brought up.