Experimental Study On Preparing Red Mad Based Composite Powder And It’s Explosion Suppression Performance

Gas explosion is one of the major disasters of mine production, which is highly destructive. The production and development of mine safety are severely restricted by gas explosions. In recent years, many experts and scholars dedicated to the study of gas explosion suppression, and have made some progress. Powder materials can be applicated in the field of gas explosion suppression to a certain degree for its excellent performance, easy storage, transportation, no poison, etc.Studied the explosion of methane-air mixture with methane concentration of 8%,9%, 9.5%, 10%, 11% by using the self-built gas explosion experiment platform. The results indicate that gas explosion flame propagating has three characteristic stages appear with laminar flame acceleration, tulip flame be found while speed slow down,turbulent flame appear promote speed be faster; explosion pressure has three stages of change: pressure rise, pressure oscillation, reverse pressure impact according to pressure sensor and photoelectric sensor. In combination with explosion flame pictures,photoelectric sensor and pressure sensor data signal. It is showed that flame speed is determined by explosion pressure to a certain extent. Flame speed is determined by explosion pressure to a certain extent in a one end opened pipeline.The superfine red mud powders, with a high specific surface area(255m2/g), were obtained after dealkalization and modification from red mud in Bayer process. The gas explosion-suppression properties of the modified red mud powders were researched by self-designed experimental system. The results indicate that the modified red mud powders presented excellent gas explosion-suppression properties. The maximum explosion pressure was decreased about 30%, and the time of pressure peaks appeared was delayed about 35%, when the methane volume concentration 9.5% and the powders concentration was 0.15g/L.Prepare red mud based urea composite materials using immersion method with modified red mud and urea. Comparison the explosion suppression results by four samples such as:modified red mud, urea, red mad based 10% urea and red mad based20% urea. Red mad based 20% urea has the best explosion suppression effect with the concentration of 0.08g/L, the explosion flame propagation distance is minimal withinthe same time, the maximum speed of flame was down to 45m/s, the maximum pressure of explosion was down to 66.1mbar from 116 mbar, it was decreased about43%. Composite powder materials has excellent performance in explosion suppression because of the synergy of modified red mud and urea in explosion.Paper be based on the theory of gas explosion and explosion-suppression, studied on explosion-suppression effects and mechanism of modified red mud and red mud based urea composite materials.