Experimental Study On Determination Of Calorific Value Of Coal Based On 5E Automatic Calorimeter

Coal is the main fuel of the thermal power plant.The cost of coal burning accounts for 80% of coal-fired power generation.Hence the calorific value of coal is an important basis of the thermal power plant production operation,cost accounting of the power generation and energy efficiency.The accuracy of coal calorific value determination plays an important role in maintaining the interests of enterprises and reducing trade disputes.It also has a dual meaning for safe production and economic operation of thermal power plants.With the development of computer technology,the calorimeter has been greatly improved in structure and operation mode,in which the automation degree is greatly improved accompanied with a higher measuring speed as well as the precision and accuracy.Isothermal calorimeter features with comparatively simple structure,easy operation,low failure rate,convenient maintenance and high efficiency,which has reached widely application in electric power,coal mine,environmental protection,metallurgy,petrochemical and scientific research fields for measuring calorific value of coal,coke,oil and other combustible materials.In the practice of coal quality inspection in power plant,the results of calorific value determination are affected by many factors,such as coal sample factor,environmental factor,equipment factor,material factor,operation factor,calculation correction factor,etc.Combined with the practical working experience of coal quality inspection in power plant,the influence factors of coal calorific value determination results in the laboratory were analyzed.The 5E isothermal automatic calorimeter was produced by Kaiyuan Instrument Factory.The calculation was based on the national standard GB/T 213-2008 entitled “Method for the determination of calorific value of coal".The influences of calorimeter heat capacity calibration,laboratory ambient temperature,continuous measurement times,and oxygenation condition on the calorific value determination results are discussed.The laboratory methods of improving coal calorific value determination accuracy and reducing the out-of-tolerance times of determination results are summarized which benefit for the calculation of coal calorific value for the coal fired power plants.