基于BBR体系的提高综放开采顶煤采出率工艺研究  

Research on technology of improving top-coal recovery in longwall top-coal caving mining based on BBR system

作　　者：王家臣[1,2] 张锦旺[1,2] 陈祎 

机构地区：[1]中国矿业大学(北京)资源与安全工程学院,北京100083 [2]放顶煤开采煤炭行业工程研究中心,北京100083

出　　处：《矿业科学学报》2016年第1期38-48,共11页Journal of Mining Science and Technology

基　　金：国家自然科学基金煤炭联合基金(U1361209);国家重点基础研究发展计划(973)(2013CB227903)

摘　　要：对放煤工艺进行优化是提高综放开采顶煤采出率的主要途径之一。本文基于BBR研究体系,采用散体放煤试验和离散元数值计算相结合的方法,从煤岩分界面特征和顶煤放出体发育的角度研究了多口同时放煤、分段逆序放煤的散体顶煤放出规律及提高顶煤采出率的机理。研究表明:采用多口同时放煤的方式可提高顶煤采出率,多回收的部分主要来自于工作面中部的中高位顶煤;随着放煤口长度的增大,放出体体积呈线性增大,初始矸石混入点位置向放煤口上方移动,终止煤岩分界面形态逐步呈现出向已放煤侧凸出的特征;采用分段逆序放煤方式可使下端头顶煤采出率提高13.98%,且在正、逆序段衔接处可形成有利于放出体发育的煤岩分界面形态,减少了采空区残煤;逆序段放煤量增长率随逆序段长度增大呈现出先增大后减小的趋势;采用分段逆序双口同时放煤方式,可达到同时提高工作面中部和下端头顶煤采出率的目的。The optimization of drawing parameters is one of the major ways to improve top-coal recovery in longwall top-coal caving mining.Based on the BBR system,the drawing mechanism of loosen top-coal in mutil-openings and partially reverse drawing techniques were analyzed by loose top-coal drawing experiments and distinct element numerical calculations.The results show that the top-coal recovery ratio in mutil-openings condition is larger than that in single-opening condition.The increased volume comes from the middle and upper parts of the top-coal above the central face.With the increasing of opening length,the volume of drawing body increases linearly and the rock mixed position in drawing body moves to directly above the opening; the shape of the boundary of the top coal appears the bulging characteristic toward the goaf gradually.The partially reverse drawing technique increases the top-coal recovery ratio in the lower end of the face by 13.98% compared to normal drawing technique.The shape of the boundary of the top-coal near the junction of reversed segment and normal segment is beneficial to the development of drawing body,which decreases the residual coal in the goaf.With increasing reversed segment's length,the growth rate of the drawing volume in reversed segment decreases after an initial increasing phase.The top-coal recovery ratios in both the middle and the lower parts of the face are increased by using the partially reverse drawing technique with double-openings.

关 键 词：BBR 多口放煤 分段逆序放煤 放出体 顶煤采出率 

分 类 号：TD823.49[矿业工程—煤矿开采]