Study On Characteristics Of Cement-Based Fire Prevention And Extinguishing Material And Its Engineering Application

China is the world's largest producer and consumer of coal and one of the few countries with coal as the main energy source.Coal,as a primary energy,plays a decisive role in China's energy structure.However,the production capacity of coal mines in China is seriously affected by mine fires,and a large number of working faces are forced to close due to fire.As an important technical means to prevent coal spontaneous combustion,roadway spraying can effectively reduce air leakage and prevent spontaneous combustion accidents caused by low temperature oxidation of broken floating coal and coal pillars in roadway roof fall area and goaf area.At present,there are two main types of spraying materials in roadways:concrete and chemical polymer materials.Concrete material is easy to crack under stress and the price of chemical polymer material is expensive.The application of spraying fire prevention and extinguishing technology in the prevention and control of coal spontaneous combustion is seriously hindered by the above reasons.In order to make up for the shortcomings of the above material,Cement-Based fire prevention and extinguishing material is proposed in this paper.Cement-Based fire prevention and extinguishing material is composed of cement,adhesives and flame retardants in a certain proportion.It has good mechanical properties,high bonding strength,compact structure,low rebound rate,low raw material price,and hardly produces dust during spraying operation.In order to cooperate with the construction of materials,a mobile spraying equipment has been developed,which is small in size,high in efficiency and flexible in underground application.In order to better grasp the properties of materials,the flame retardant properties and air tightness properties of materials were experimentally and numerically simulated.According to the experiment,the material belongs to non-combustible material,which meets the requirement of underground coal mine.The structure of the material is observed by scanning electron microscopy,and there are no large voids and cracks are not developed,and the structure is compact.The air tightness test of Cement-Based fire prevention and extinguishing material and concrete material shows that the air tightness of Cement-Based fire prevention and extinguishing material is obviously better than that of concrete material widely used at present in the same observation time.Through the use of FLUENT simulation software to simulate the air flow field in the roadway before and after spraying Cement-Based fire prevention and extinguishing material,and the industrial test in 3203 auxiliary transport channel of Tarawa Coal Mine,...