Retardant Technology and Application for Residual Coal in Goaf Based on Pulverized Fuel Ash-cement Foam Material

For the problems of low plugging strength, high cost and damaging environment of existing coal mine fire prevention materials, the pulverized fuel ash-cement foam material is prepared from the following components by weight: 10% to 40 % of sulfoaluminate superfine cement, 10% to 40 % of pulverized fuel ash, 0.5% to 0.9 % of carboxymethyl cellulose, 0.1% to 0.6 % of sodium fluoride, 0.2% to 0.6 % of melamine, 0.1% to 0.4 % of aluminum sulfate, 0.3% to 0.6 % of lauryl sodium sulfate, 0.4% to 0.6 % of sodium dodecyl benzene sulfonate, 0.5% to 0.8 % of saponin and the balance of water. The rate of temperature in coal face can reduce effectively by using the method of pulverized fuel ash-cement foam material.