室温下孔隙结构、空气湿度和粒径对煤低温氧化的影响

Effects of pore structure, air humidity and particle size on coal oxidation at low temperature under room temperature

为研究室温下煤对氧气的吸附情况,选择不同变质程度的样品,利用氮吸附法、介孔分析模型(berreit joyner halenda,BJH)和多层吸附方程(brunauer emmett teller,BET)计算并分析样品的孔隙结构,在不同空气湿度和粒径条件下测定样品的氧气吸附量。结果表明:氧气吸附量与微孔体积呈正相关,与平均孔径呈负相关;随着空气湿度的变化,氧气吸附量先增加再减小;粒径对吸氧量的影响较为复杂,随着粒径的减小无烟煤氧气吸附量大幅度减小,长焰煤、褐煤和烟煤的吸氧量先增加后减小。本研究对抑制煤在常压下发生低温氧化具有重要的理论和现实意义。

In order to study the adsorption of oxygen to the coal under indoor temperature,samples with different degrees of deterioration were selected,by low pressure adsorption N2 method,the combination of berreit joyner halenda(BJH)and brunauer emmett teller(BET)equations calculation to analyze the pore structure of the samples.The oxygen adsorption capacity was measured under different air humidity and particle size conditions.The results showed that the oxygen adsorption capacity was positively correlated with the micropore volume and negatively correlated with the average pore size.With the change of air humidity,the oxygen adsorption capacity increases firstly and then decreases.The influence of particle size on the oxygen adsorption of samples is more complex.With the decrease of particle size,the oxygen adsorption capacity of anthracite decreases sharply,while the oxygen adsorption capacity of long-flame coal,lignite and bituminous coal increases and then decreases.This study has important theoretical and practical significance for inhibiting the low temperature oxidation of coal at normal temperatures and pressures.