宁东能源基地是国家规划的13个亿吨级大型煤炭基地之一,是国内少有的百亿吨级整装煤田,随着各矿井陆续投产,常规开采中“三下”压煤、保护煤柱及边角残煤等引起了大量的煤炭损失,这与国家可持续发展的国策不符,而穿巷开采是回收宁东煤田“三下”压煤条带煤柱可行的办法,为此需要解决好三个关键问题:首先,在综合考虑地质条件等因素后确定技术方案,同时结合理论分析与现场监测等手段,做好“采留比”的设计,主要包括确定巷道临界宽度和兼顾经济性和安全性的最小煤柱宽度;其次,要控制好掘采后巷道的充填质量,必要的时候可以在充填体中注浆,以提高充填堆积体的整体强度和空间刚度,增强充填体对顶板的支撑能力和对煤柱的约束强度,以减轻顶板大范围离层;最后,为了保证穿巷开采的顺利实施,在开采工艺上可以采取间隔式跳采法,这样大大降低了掘采过程中巷间煤柱失稳的概率,提高了永久损失煤柱回收的效率。通过实施穿巷开采,地面基本实现无矸石堆存,地表沉陷和次生地质灾害得到有效控制,地下水系和地面生态环境破坏程度大幅度降低,实现绿色开采。
Ningdong energy base is one of the 13 large-scale coal bases about billion tons,and is a rare ready coal field of tens of billion tonnes of class. As coal exploration boomed,such as"three-under"pressure coal,protective coal pillar and boundary coal-pillar have caused massive coal loss subjected to conventional design. This is not in conformity with national policy for the sustainable development,however,the mining technology through excavation-mining is a feasible way to recover these coal pillars. Therefore,three key problems need to be solved:First,the relationship between the exploitation and leave behind need to be scientific decision,as considering geological conditions and other factors,meanwhile,combining with theoretical analysis and field monitoring. The main contents include the roadway critical width and minimum width of coal pillar that combination to economy and safety of; Next,the filling quality need to be guaranteed after excavation-mining,if necessary,grouting reinforcement also can be used for filling accumulation body. The aim is to improve the overall strength and space effective stiffness about the filling body,and enhance the support ability of filling body for roof and constraints strength for the coal pillar; Finally,in order to guarantee the successful implement of excavation-mining,the interval type jump mining method can be used,and it can greatly reduce the probability of coal pillar,and improve the efficiency of coal pillar recovery. If the mining technology through excavation-mining is used,the gangue will be utilized and the gangue will not exist in ground,meanwhile,the underground drainage system and the ecological environment less damage will be restrained,and finally will realize green mining.