Adsorption Equilibrium Time Affected to Initial Velocity of Gas Emission

Abstract：The adsorption time of coal sample stipulated in the safety production industrial standard AQ1080-2009 Measuring Method of Coal Gas Emission Initial Speed Index （Δp） was 90 min. In order to verify the limitation of the standard in certain application, the coal samples with different relative high volatile matters from five mines were selected to the measuring experiments of the gas initial emission speed. The paper analyzed the adsorption equilibrium time affected to the initial velocity of gas emission and studied the adsorption equilibrium time of different metamorphic degree coal samples to the influence law of the initial velocity of gas emission. The experiment results showed that the lower volatile matter of the coal, the longer of the adsorption equilibrium time required and the higher measured value would be. The initial velocity of gas emission was highly affected by the adsorption equilibrium time. When the adsorption equilibrium time was 90 min, the initial velocity of gas emission would be increased continuously and would be in stable finally. Finally, the suitability of the present available standard to different type coal was analyzed with test. The analysis showed that the adsorption time stipulated in Measuring Method of Coal Gas Emission Initial Speed Index （Δp） would have certain limitation. As for the high metamorphic degree coal sample, the measured value would not be reached the requirements of the adsorption saturation value and the adsorption equilibrium time should be properly expanded.