厚煤层协调全采沉陷控制技术及在村庄下采煤中的应用

Subsidence control by coordinated full-area mining of thick coal seam and its application in mining under villages

我国煤矿“三下”压煤严重,滞压资源的回采与受护对象的保护存在矛盾,寻求解决资源高采出率与受护体安全问题的办法,是我国矿山开采沉陷研究长期以来的一个技术难题。针对条带开采资源采出率较低、充填开采成本较高、同步协调开采实施难度较大的问题,考虑煤矿主要地质采矿因素,基于开采沉陷基本规律、上下煤层重复开采影响规律和采区内多工作面的相邻开采影响规律,提出了村庄下厚煤层横向采宽控制、纵向分层采厚控制、开采顺序优化控制的联合协调控制技术思路和采区内工作面跳采、全采、分层开采3个阶段沉陷控制方法。为了提高技术应用效果,提出了开拓系统单翼布置和大采区、长工作面的优化设计方法。通过实测和理论分析,揭示了协调式跳采全采方法精准控制地表变形、改善村庄地表变形过程和分布状况的机理,得出了开采各阶段工作面优化设计参数。经过不同煤厚、不同采深条件的多个矿井20 a的应用研究,解放了大量滞压资源,实现了多个村庄下滞压资源的安全高效全采,采厚3.5~5.7 m、跳采宽度达305 m、年度出煤量达128万t/a,村庄煤柱采出率达到93.5%,避免了上千户村民的搬迁和异地耕作,创造了良好的经济和社会效益。

In China,some coal resources are severely stagnated by buildings,railways,water bodies and others,and there is a contradiction between the recovery of stagnated coal resources and the protection of protected objects.It has been a technical problem for a long time to find a solution to the problem of a high resource extraction rate and the safety of protected objects in China's mining subsidence research field.In view of the problems of low recovery rate of stagnant resources by strip mining,high cost by filling mining and difficulty by implementing synchronous coordinated mining,this paper puts forward some technical ideas of coordinated control of combinations with horizontal mining width control,vertical stratified mining thickness control and mining sequence control of thick coal seam under villages.In addition,the subsidence control methods of three stages of skip mining,full-area mining and stratified mining of working face are proposed.In order to improve the application effect of the technology,the single wing layout of the development system and the optimization design of large mining area and long working face are put forward.Through some actual measurements and theoretical analysis,the mechanism of coordinating all-mining method to accurately control surface deformation and improve the process and distribution of village surface deformation is revealed,and the optimal design parameters of working face at each stage of mining are obtained.After 20 years of application research in several mines with different coal thicknesses and mining depth conditions,a large number of stagnated resources have been extracted,and the safe and efficient mining of stagnated coal reserve under several villages has been realized.The mining thickness is 3.5-5.7 m,the jump mining width is 305 m,and the annual coal output is up to 1.28 million t/a,The yield rate of coal pillar in the village has reached 93.5%,which brings some social and economic benefits,avoiding the relocation of thousands of villagers.