Recently, Shendong Coal held an on-spot meeting to share experiences on gob-side entry retaining (GER) and safety work, comprehensively analyze and review its GER work, sum up lessons from typical experiences, and make plans for further application in practice.
Over the past three years, Shendong Coal has actively expanded the utilization of GER technology. It has retained roadways totaling 34,013 meters in 18 working faces of six coal mines, reduced roadway excavation by 40,816 meters, and recycled 2.04 million tonnes of additional coal, with economic return of 740 million yuan. The company has increased its resource recycling rate by 5 percentage points, and created the record entry retaining speeds of 18 meters/day and 418 meters/month at 4.2-meter-thick coal seam as well as the historic high of 5,190 meters in single-side entry retaining. Moreover, the technology has been applied in the company’s all working faces without severe disasters and with a mining height below 4.5 meters. The “research and application of safe, efficient non-pillar coal mining technology of Shendong Coal” topped the winners of the Special Prize of China Energy’s Encouragement Fund in 2022.
At present, the company’s GER technology has become increasingly mature, and its support methods are getting more scientific. Technologies for “one ventilation and three preventions” have been further optimized, and remarkable achievements have been made in technological integration. The utilization of GER technology not only reduces costs, but also increases the recycled coal resources. More importantly, it helps save excavation manpower, simplify the layout of the production system, relieve pressure on excavation continuity, eliminate the centralization of roof stress, and minimize the fire risks of coal mine gobs, thus guaranteeing workplace safety.
