自燃煤矸石山非稳态温度场演化规律研究

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中图分类号：TD75 文献标志码：A

Abstract：Existing studies on the spontaneous combustion of coal gangue mountains mainly focus on constructing simplifiedairflow seepage models，often neglecting the efectsof internal convective heat transfer， stacking forms，andspatial distributioncharacteristicsof porosityonthe temperaturefieldof spontaneous combustion incoal gangue mountains.Toaddressthese isues，amulti-field coupled numerical simulationof the temperature，seepage，and oxygen concentration fields during the spontaneous combustion processofcoal gangue mountains with two diffrent stacking forms—dumped along the slope and piled up on flat ground—was conducted usingFluent software.The spatiotemporal evolution patterns of oxygenconcentration and temperature fields were analyzed. The results showed that： ① the internal oxygen concentration of the coal gangue mountain decreasedrapidlyat first and then gradually with increasing distance from theslope surface and top surface.The areaof low-oxygen-concentration regions increased gradually with time，while the average internal oxygen concentration decreased over time with a gradually decreasing rate of decline. ② The internal temperature of the coal gangue mountain increased over time，and the heating rate gradually decreased.In both horizontal and vertical directions，the temperature exhibited similar variation paterns—itroserapidlyat firstand then slowly decreased with increasing distance from the slope surface and the bottom surface.The high-temperature region was mainly concentrated at a distance of 1-6m from the slope surface and at 40%-90% of the vertical height （measured from the bottom of the coal gangue mountain）. ③ The surface temperature of most regions of the coal gangue mountain was below 100c ， with only a few areas ranging from 100 to 110qC . The temperature variation trends ofthe slope surface and the top surface were consistent， but the top surface temperature was slightly higher than that of the slope surface.

Key words： coal spontaneous combustion; coal gangue mountain; temperature field; seepage field; oxygen concentration field; multi-field coupling

0 引言

煤矸石排放量占原煤总产量的 15%～20% ，是我国排放量最大的工业废弃物之一[]。（剩余14094字）