The fire extinguishing performances of foamed gel in coal mine

Experiments have been made to investigate how mass concentrations of thickener and crosslinker blends and foaming multiple affect temperature resistance of foamed gel. The results show that, at 100 °C, the time for temperature tolerance of common foam is only 196 s, while the time of foamed gel formed by thickener and crosslinker with the mass fractions of both 0.3, 0.4 and 0.5 % is 570, 604 and 780 s, respectively. When the foaming multiple is 5, the time for temperature resistance is 620 s. But the time reduces to 360 s as the foaming multiple increases to 30. Furthermore, researches are also conducted on the extinguishing effect of foamed gel. It can be known from the results that, when putting out the coal fire with similar size, the volume of foamed gel used is only one-ninth of that of common foam and the extinguishing time is less than half of common foam. With increasing in the mass concentration of thickener and crosslinker blends, the extinguishing time first shortens and then prolongs. When the mass fraction of complex solution mixed by thickener and crosslinker is 0.6 %, the extinguishing efficiency is the highest. If the foaming multiple is 5, the extinguishing time is the shortest. However, the time remains constant when the foaming multiple is over 20.