Preparation And Properties Of Expandable Gel Foam For Preventing Spontaneous Combustion Of Coal

Coal is an important part of China’s energy structure and plays an important role.In order to ensure coal mine safety and efficient production,fire prevention and extinguishing is particularly important.In this paper,the gel foams with high water retention and good film forming properties were prepared by modifying the traditional sodium silicate gel foam.Secondly,in order to solve the problem of gel foam burst and water evaporation to reduce the fire suppression effect when the gel foam fire is high,the gel foam technology and the intumescent flame retardant technology are combined organically,and the expansive function of the gel foam is developed,and the fire extinguishing performance is studied.The main contents of this paper are as follows:Pure water glass(WG)gel foam has the disadvantages of low strength,poor foam stability,poor gel strength and poor water retention.In view of the above problems,the water retaining agent and film forming agent were introduced into the WG gel foam,and the water glass gel foam was optimized.Finally,the WG gel foam with high water retention,high foam stability and good film forming property was prepared.The results showed that the best compound system of WG gel foam was:Twelve alkyl alcohol ether sulfate sodium(AES)and twelve alkyl sulfate(SDS)were prepared according to 1:2 ratio,the concentration was 0.8%,the gelling agent WG concentration was 8%,and the crosslinking agent NaHCO3.The concentration of 3 is 2%,the concentration of polyacrylamide is 0.4%,the concentration of film～forming agent a is 1%,and the concentration of water retaining agent B is 0.3%.The modified WG gel foam has a more compact network structure,good stability and good film formation.The half～life at room temperature is forty days.In order to further improve the effect of fire extinguishing,it is necessary to solve the problem of gel foam breaking and water evaporation resulting in the reduction of fire extinguishing effect when the gel foam is extinguishing at high temperature.The microencapsulated flame retardant(MPA)was blended with pentaerythritol into the gel foam prepared by the above method,so that the gel foam technology combined with intumescent flame retardant technology could be used to prepare a kind of gel foam with expandable function.The structure of the study showed that compared with raw coal,the CO release of the coal samples treated with expansible functional gel foam decreased significantly from 200 ppm to 7126.41ppm at a temperature of 17263.69 7126.41ppm,indicating that the gel foam with expandable function had an obvious inhibitory effect on the oxidation of coal.The fire test showed that the coal temperature remained at 609 C at 230min when the coal sample treated by the unmodified pure water glass gel foam was treated.The coal samples treated with expansible gel foam decreased to 33 degrees at 230min,indicating that the prepared gel foam had excellent fire extinguishing effect.Figure[35]Table[13]References[111]...