Study On Influencing Factors And Forcast Index Of Spontaneous Combustion Of Pulverized Coal In Thermal Power Plant

Thermal power plants for industrial production and residential life to provide the most basic demand for electricity to ensure that China's current 50%of the coal directly used in thermal power plants for coal-fired power generation,in the process of raw coal need to crush,grinding and other processes into coal Powder,into the combustion boiler to make it fully burned.Large-scale power plant grinding process using the majority of vertical coal mill system,in order to remove the raw coal water on the impact of coal,coal mill system will be pre-access to hot air,coal particle size is small(20?50?m)and the mill Dry atmosphere(temperature above 60?)prone to spontaneous combustion of coal,so the need for reliable forecast technology ahead of warning.Based on the relevant literature and field investigation,this paper chooses five kinds of coal samples with different metamorphic degrees by means of theoretical analysis and experimental verification.The coal is pulverized and pulverized into the same range of pulverized coal with the same power plant.In order to ensure the effectiveness of the forecasting parameter index,the coal preparation system of the power plant is preheated by the hot air drying and the heating chamber,and then the coal spontaneous combustion process is carried out for each coal type.In this paper,Temperature test.Under the combination of experiment and theory,the gas and parameter values of coal spontaneous combustion warning index are obtained.In order to reduce the accident of the experiment and to provide more indicators of coal spontaneous combustion in the field,the experimental parameters were changed and the spontaneous combustion forecast of pulverized coal was further studied.By changing the coal particle size,air flow and heating rate and other parameters of the conditions,test the spontaneous combustion of coal powder gas species and concentration changes.Because of the different coal types,the selected forecast indexes are different.In the actual production,the factors such as the inaccurate and even the conflicting index of the same coal are prevented,and the reliability of the index gas and the parameter value of the experiment is evaluated by gray correlation analysis,That is,by calculating the correlation degree between the index gas and the coal spontaneous combustion program temperature experiment,the reliability of the index gas is evaluated,and the first three kinds of gas with the highest correlation degree are selected as the spontaneous combustion forecasting gas of the corresponding pulverized coal.There is a danger of spontaneous combustion of pulverized coal in power plant pulverizing system.Only timely and accurate forecasting can reduce the influence of spontaneous combustion of pulverized coal on production safety.Therefore,it is pointed out that the spontaneous combustion early warning index of pulverized coal has certain guiding significance for coal spontaneous combustion prevention.