Automatic Control Of Limestone Semi Dry Desulfurization

In this paper,the importance and necessity of desulfurization in China and the history of desulfurization technology are introduced,at present the desulfurization technology by analysis and comparison,process characteristics of semi dry flue gas desulfurization technology is expounded,at the same time the control function of Huangling mining coal gangue power generation limited company 2×50MW unit circulating fluidized bed desulfurization and denitration renovation project and dedusting system according to the requirements.Starting from the structure of the control system and the design scheme of each control subsystem,the design scheme of each system is studied,and the design scheme is put forward.In order to ensure the safety and economic efficiency of flue gas desulfurization and flue gas desulfurization equipment for the operation,process characteristics and control system compatibility and control equipment is considered to maximize the availability,reliability,controllability and maintainability.The main contents are as follows.1.The urgent requirement of the current situation,harm and S02 emission control analysis of atmospheric pollution in China;the application and development of all kinds of flue gas desulfurization technology of flue gas desulfurization at home and abroad are summarized;the development trend of process control technology,the latest development and application in desulfurization control field were investigated and analyzed,and the main thought,desulfurization control system based on the engineering design of the target and scheme was proposed,and has carried on the system design and debugging.2.According to the characteristics of semi dry flue gas desulfurization technology,the control requirements of desulfurization system and the specific control method of the control object are put forward.The main control methods of semi dry FGD control system adopted is put forward,in accordance with its functions:data acquisition(DAS),analog control(MCS),sequence control(SCS)of three modules;structure and control system is a hierarchical design.3.Based on the analysis of factors of semi dry flue gas desulfurization system operation mechanism and effect on Design of control loop is mainly including:MCS desulfurization tower pressure control,desulfurization tower of sulfur dioxide concentration control,desulfurization tower outlet flue gas temperature control.According to the above control circuit of the controlled object working process and characteristics,influencing factors,discussion,through the control circuit under different conditions control mode and fault processing method are compared and analyzed.The hybrid particle swarm optimization(PID)algorithm is proposed to optimize the control of SO2 concentration and flue gas temperature in the flue gas.The test results show that the improved system can reach the national standard of desulfurization and dust removal.In summary,in this paper,semi dry flue gas desulfurization control system is studied and designed.Finally,combined with the practical application effect of the plant,may indicate that the control system can meet the need of control of circulating fluidized bed semi dry desulfurization,desulfurization efficiency and reduce energy consumption levels,to meet the design requirements to meet the requirements of environmental protection,emission concentration.