Research On Factors Affecting Coal Calorific Value

The importance of coal chemical industry is analyzed in detail in the view of the effective use of the natural resources in our country. The significance is discussed about the research and development on coal chemical technology. The factors influencing the calorific value of coal were researched by a set of designed experiments. Based on the analysis to the experimental results, some conclusions are obtained. The calorific value of coal has a certain relationship with the sample size and storage time. The larger the size of the sample, the worse the repeatability of the calorific value. The longer the sample storage time, the more obvious the reduction of the calorific value. With the increase of coal moisture and ash content, calorific value is gradually become smaller. The moisture in coal is the most useless component. It will absorb the heat of coal combustion because it is changed into stream in the combustion process. The water combined in coal can be released by heating at high temperature for a long time. Ash is a product of minerals oxidation and decomposition in coal, it can’t be oxidized to produce heat. The increase of moisture and ash ratio led to a decline in organic matter content in the coal. The influence of the sulfur content on coal calorific value is small, but it is the harmful substance in coal. The gas released by combustible sulfur has obvious pollution to the environment. Carbon, as the most component of organic matters in coal, its content in the coal had the greatest influence on the calorific value of coal. For the combustion process of organic matter, the carbon content directly can be used as the standard of coal calorific power and coal quality before carbon content reaches a certain proportion. As the carbon content rises furtherly, calorific value is gradually reduced.