摘要
矿井生产中注氮防灭火技术为防治采空区遗煤自燃所普遍采用的主要技术措施,但由于常温氮气对采空区无降温特性,不能有效消除采空区高温点。采用FLUENT模拟了工作面现阶段条件下低温氮气注入前后采空区流场及温度场变化规律,并进一步选取了最优注低温氮气方案,随后在现场利用氮气冷却装置,将低温氮气输送至采空区,研究低温氮气对采空区氧气和温度的影响。结果表明,采空区注氮后,采空区散热带、氧化带面积显著减少,约为注氮前的一半以下,窒息带出现了较大的增加;注入低温氮气后,采空区温度以注氮口为中心呈椭圆形扩散,逐渐增加;选取了温度为-40℃、注氮口位置为10 m、注氮量为750 m^(3)/h的现场注氮方案,测温光纤实时监测结果表明,注氮口的温度相较于注入常温氮气降低了48.8℃,回风侧采空区温度相较于注入常温氮气降低了19.1℃。
The nitrogen injection fire prevention and extinguishing technology is commonly used as the main technical measure to prevent spontaneous combustion of residual coal in goaf during mine production.However,due to the lack of cooling characteristics of normal temperature nitrogen on goaf,it cannot effectively eliminate high temperature points in goaf.The FLUENT was used to simulate the flow field and temperature field changes in the goaf before and after low-temperature nitrogen injection under current working conditions,and the optimal low-temperature nitrogen injection scheme was further selected.Subsequently,a nitrogen cooling device was used on-site to transport low-temperature nitrogen to the goaf,studying the effect of low-temperature nitrogen on oxygen and temperature in the goaf.The results showed that after nitrogen injection into the goaf,the area of the dispersion and oxidation zones in the goaf significantly decreased,which was less than half of that before nitrogen injection,and there was a significant increase in the suffocation zone;after injecting low-temperature nitrogen,the temperature of the goaf gradually increased in an elliptical shape with the nitrogen injection port as the center;the on-site nitrogen injection plan with a temperature of-40℃,a nitrogen injection port position of 10 m,and a nitrogen injection rate of 750 m^(3)/h was selected.The real-time monitoring results of the temperature measurement fiber showed that the temperature of the nitrogen injection port decreased by 48.8℃compared to injecting normal temperature nitrogen,and the temperature of the goaf on the return air side decreased by 19.1℃compared to injecting normal temperature nitrogen.
作者
樊永勇
王新瑞
张春雷
Fan Yongyong;Wang Xinrui;Zhang Chunlei(CHN Energy Xinjiang Energy Co.,Ltd.,Urumqi 830000,China)
出处
《能源与环保》
2024年第11期254-262,共9页
CHINA ENERGY AND ENVIRONMENTAL PROTECTION
基金
国家自然科学基金资助项目(52174194)
2018年新疆维吾尔自治区引进高层次人才天池百人计划(新人社函[2019]39号)。
关键词
采空区
遗煤自燃
低温氮气
采空区自燃“三带”
数值模拟
goaf
spontaneous combustion of residual coal
low-temperature nitrogen
"three zones"of spontaneous combustion in goaf
numerical simulation