Flexible Liner for Use in Advancing Tailgate

摘要

This report describes an investigation on the technical and economic feasibility of implementing flexible liner-backpacking support systems in an advancing tailgate longwall mine. The system consists of a circular tube constructed of liner plates and flyash backpacking. Flyash is pneumatically stowed into the tailgate. Small amounts of cement may be mixed to improve the support capability of the fill in difficult local ground conditions. Water is added inside the nozzle immediately prior to spraying. Results of theoretical analyses and a field test show that the designed system is technically feasible, can be cost-competitive, provides more stable ground conditions, and can increase productivity and coal recovery, compared with existing retreat longwall systems. In certain mine layouts, the system can reduce the direct mining costs by a significant amount and would be particularly applicable to deeper coal beds with bad ground conditions.