Control Method Research On Coal Fired Steam Boilers

Coal fired steam boilers are an important thermal power equipment widely used in power plant,industrial production,urban heat supply and other fields.There are about600000 coal-fired boilers in China which burn about 700 million tons of coal annually,and emit 9 million 800 thousand tons of soot and sulfur dioxide,accounting for about 30% of the total emission of the country.In November 2014,the national development and Reform Commission,bureau of energy,Ministry of environmental protection,the Ministry of Finance and other seven ministries jointly issued the "comprehensive upgrading of coal-fired boilers energy saving project implementation plan" requirements,to 2018 transformation of coal-fired steam boilers 400 thousand tons,500 thousand tons of steam boiler to promote efficient.The main measures are to improve boiler equipment and automatic control technology,improve combustion performance and operation efficiency,and realize coal saving and standard discharge.This paper mainly studies the operation control of industrial coal-fired steam boiler.The main research contents and work are as follows(1)The structural characteristics and operation process of coal-fired steam boiler are introduced.The main points of control problems are summarized,and the task of control system is put forward.(2)Analyzing the dynamic characteristics of the controlled object of boiler water level,analyzing the relationship between mass and energy transfer,and establishing a mathematical model to design the water level control scheme.(3)Analysis of boiler steam pressure controlled object dynamic characteristic analysis,energy transfer relationship,establish the mathematical model of every link,control scheme design,mainly around the coal volume regulation and drum pressure control,air conditioning and air fuel ratio control and air volume regulation and furnace pressure control.