浅埋深超大采高综采工作面过地表沟流防治水技术

Water prevention technology of shallow-buried depth and super large mining height fully-mechanized mining face passing surface channel flow

地表沟流对浅埋超大采高综采工作面的回采影响主要有2个方面,一是地表水通过导水裂缝渗入采空区,威胁生产安全;二是地表沟流成因使得流经区域基岩较薄,井下回采矿压显现不明显,坚硬煤体对生产造成不利影响。以上2类问题看似互不相干,却通常同时存在,成为矿井安全高效回采的难题。以神东矿区上湾煤矿12402工作面为例开展研究,研究了该环境下地表塌陷等情况,在此基础上提出了浅埋藏、超大工作面工作过地表沟流防治水措施,包括疏放地表积水、回填塌陷河床、加高堤坝等综合治理措施,用以保证河道畅通,提高河床防渗性,从而达到防治水的目的。此外,通过井下探放含水层等关键技术,解除了含水层涌水威胁;通过增大工作面及巷道的排水能力,有效解决了工作面涌水问题;未通过调整底板坡度,就达到了减少采空区积水的目的,使采空区内积水排向防水点,避免了采空区积水进入工作面,通过以上井下综合防治水措施可从时间和空间上分解防治水压力,达了较好的防治水效果。为了保证沟流下放工作面安全生产,结合基岩薄、埋藏浅矿压显现特征,采用数值模拟、现场试验等方法,提出了水力压裂弱化煤体强度来解决坚硬煤体强度的方法,通过数值模拟确定了压裂参数,优化了压裂设计方案,并在实际生产中不断完善,降低了煤体能耗,达到了保护设备和除尘降尘的效果。

There are mainly two aspects of the influence of surface ditch flow on the mining of shallow-buried and super-large mining height fully mechanized working faces.First,the surface water seeps into the gob through the mining fissures,which threatens the production safety.The second is that the formation of surface gully flow makes the bedrock in the area flowing through is thin,the underground mining pressure is not obvious,and the hard coal body has adverse effects on production.The above two types of issues seem to be unrelated,but they usually exist at the same time,and become the difficult problem for safe and efficient mining.This paper takes the No.12402 working face of Shangwan Coal Mine in Shendong Mining Area as an example,the research was carried out to studythe ground surface collapse and other situations in this environment.On this basis,the shallow-buried and super-large working face worked through the surface ditches and water prevention measures,including the surface drainage comprehensive treatment measures such as dredging the surface water,backfilling the collapsed riverbeds,and raising the dam to ensure the smooth flow of the river and improve the seepage resistance of the riverbed,so as to achieve the purpose of water prevention and control.In addition,through key technologies such as underground aquifer detection and release,the threat of water gushing from the aquifer is eliminated.By increasing the drainage capacity of the working face and roadway,the problem of water gushing at the working face is effectively solved.At the same time,the purpose of reducing the water accumulation in the gob was achieved without adjusting the slope of the floor.Through the above water control measures in the well,the water pressure can be decomposed and prevented in time and space,and a better water control effect can be achieved.In order to ensure the safe production of the working face under the ditch,combined with the thin bedrock and shallow-buried underground pressure,numerical simulation,field test and other methods are used to propose a method of hydraulic fracturing to weaken the strength of the coal body to solve the strength of the hard coal body.Through numerical simulation,the fracturing parameters were determined,the fracturing design scheme was optimized,and the actual production was continuously improved,which reduced coal energy consumption and achieved the effects of protecting equipment and removing dust.