Preparation And Study On Performance Of Three-phase Fly Ash Foam

The spontaneous combustion of coal in the mine will not only cause huge economic losses,but also seriously threaten the lives of mine employees.In order to prevent the spontaneous combustion of coal,researchers have successively proposed a variety of techniques to prevent spontaneous combustion of coal.Three-phase foam fire-fighting technology is one of the most important Kind of.Three-phase foam integrates the fire-fighting performance of three materials:solid,liquid,and gas,and uses the coverage of non-combustible solid particles,the heat absorption and cooling properties of water and the asphyxiation of inert gas to greatly improve the fire-fighting properties,and accumulation With good performance and low cost,it is widely used to prevent spontaneous combustion of coal.In this paper,through experiments,a new type of three-phase foam foaming agent was firstly formulated to compare with the commonly used three-phase foam foaming agents for mines;then the solid phase fly ash was hydrophobically modified to obtain a modified The three-phase foam blowing agent is compared with the two three-phase foam blowing agents;finally,the fire-fighting performance of the prepared two three-phase foam materials is studied.The main findings are as follows:(1)Use fatty alcohol polyoxyethylene ether sodium sulfate(AES),coconut oil diethanolamine(6501),sodium lauryl sulfate(K12),polyacrylamide(PAM),modified silicone resin polyether emulsion(FM-550)As a blowing agent,the formulation of the three-phase foam blowing agent is optimized through orthogonal experiments.The specific composition and mass ratio are:AES:6501:K12:PAM:FM-550 is 6:6:9:0.3:2.Compared with the common mining three-phase foam foaming agent,the foaming ratio of the foaming agent of this compound system is increased by 52%,and the stability is increased by 117%.It is further studied that when the mass ratio of foaming agent to water is 1:20,the solid-liquid mass ratio is 1:3,the solid particle size is less than 75 μm,and the solution pH is 6-8,the three-phase foam performance is the best.(2)By hydrophobically modifying fly ash particles,when the mass ratio of water to ethanol is 3:7,the mass concentration of silane coupling agent KH-560 is 2%,the solution pH is 3,and the solid-liquid mass ratio is 1:3,the heating temperature is 60℃,the modified three-phase foam blowing agent is obtained by ultrasonic and stirring.The modified three-phase foam blowing agent increases the stability by 81%compared with the unmodified,and there is no obvious change in the foaming ratio.The chemical mechanism of the hydrophobic modification of fly ash is theoretically analyzed,and it is known that the modified In the process,chemical bonding occurred instead of physical adsorption.(3)The fire-fighting performance of two-phase foam blowing agent,three-phase foam blowing agent and modified three-phase foam blowing agent are studied.In terms of temperature resistance,modified three-phase foam blowing agent has the strongest stability,Two-phase foam blowing agent has the worst stability;in terms of anti-burning performance,three-phase foam blowing agent is about twice that of two-phase foam;in terms of stacking performance,two-phase foam blowing agent is better,three-phase foam The foaming agent is worse,but it can still meet the needs of engineering applications.Figure[19]Table[14]Ref[104]...