摘要
为了研究粒度对采空区煤自燃极限参数的影响,采用煤自燃程序升温试验装置测试长焰煤、弱黏煤和贫煤在5种粒径下的自燃特性参数。根据试验测定的自燃特性参数计算得出煤在不同粒径情况下的自燃极限参数。试验结果表明:煤样的放热强度随煤变质程度的升高呈现降低趋势,煤样的临界温度随煤变质程度的增加而升高;最小浮煤厚度和下限氧浓度与煤变质程度呈正相关,而上限漏风强度与煤变质程度呈负相关;在煤氧化过程中,煤自燃极限参数的极值产生在自燃临界温度附近;煤样的粒度对煤的自燃极限参数有明显影响,在相同条件下,上限漏风强度随着煤粒径的增大而减小,最小浮煤厚度与下限氧浓度随着煤粒径的增大而增大;煤自燃极限参数与粒径的关系满足二次多项式的关系。试验结果可为采空区自燃危险区域判定提供基础参数。
In order to study the particle size affected to the limit parameters of coal spontaneous combustion in the goaf,a programmed temperature rising test device of coal spontaneous combustion was applied to measure the spontaneous combustion feature parameters of the long flame coal,weak coking coal and lean coal samples under the condition of five different particle sizes. According to the spontaneous combustion feature parameters measured from the test,the spontaneous combustion limit parameters of coal under the different particle sizes were calculated and obtained. The test results showed that the heat released strength of the coal samples would be in a declined tendency with the coal metamorphic degree increased and the critical temperature of the coal samples would be increased with the coal metamorphic degree increased. A minimum thickness of the coal left and the lower limit oxygen concentration would be in a positive correlation to coal metamorphic degree,the upper limit air leakage strength would be in a negative correlation to coal metamorphic degree. During the coal oxidization process,an extremum of the coal spontaneous combustion limit parameters would be occurred in the vicinity of the spontaneous combustion critical temperature. The coal particle size would have obvious influences to the spontaneous combustion limit parameters. Under the same condition,the upper air leakage strength would be decreased with the coal particle size increased and the minimum thickness of the coal left and the lower limit oxygen concentration would be increased with the coal particle size increased. The relationship between the coal spontaneous combustion limit parameters and coal particle size could meet the twice polynomial relationship. The test results could provide the basic parameters to judge the spontaneous combustion danger area in the goaf.
出处
《煤炭科学技术》
CAS
北大核心
2015年第6期59-64 53,53,共7页
Coal Science and Technology
基金
国家自然科学基金资助项目(51134019
51304135)
陕西省教育厅科研计划专项资助项目(14JK1477)
西安科技大学培育基金资助项目(201353)
关键词
煤自燃极限参数
粒径
自燃特性
变质程度
limit parameters of coal spontaneous combustion
particle size
spontaneous combustion features
metamorphic