Evaluation of Water Trap Designs and Alternative Mine Seal Construction Materials.
Weiss-ES; Slivensky-WA; Schultz-MJ; Stephan-CR
Proceedings of the 27th International Conference of Safety in Mines Research Institutes, February 20-22, 1997, New Delhi; Oxford and IBH Publishing Co. Pvt. Ltd., New Delhi, 1997 1997:973-981
The results of a study being conducted by NIOSH and the US Department of Labor, Mine Safety and Health Administration, on the effectiveness of water trap and seal designs for use in underground coal mines were reported. The effectiveness of two water pipe trap designs (15 and 30 centimeter diameters) and one water trough trap design in preventing the passage of an explosion flame through the trap and/or maintaining the water level within the trap under explosion conditions were studied. None of the water trap designs tested demonstrated adequate performance. In order to improve the function of the traps, the designs were modified by adding an additional course of block around the water trough area on the active side of the seal in the water trough trap design and by extending the pipe on the water pipe trap design vertically on the active side of the seal while maintaining the water behind the seal at the lowest possible level. These modifications successfully raised the water level of both seals and increased explosion protection. Newly developed composite polymer seal designs consisting of two dry stacked, hollow core or solid concrete block walls with a polymer and limestone aggregate and a foam polymer pumped separately into each aggregate layer were tested. A seal constructed with a 51 centimeter thick, 203 kilogram/cubic meter density, polymer foam core, between two concrete block walls, had acceptable performance in explosion tests and was approved for use in coal mines. A cellular concrete seal was also found to be an acceptable seal design material.
Safety-engineering; Coal-mining; Worker-health; Explosion-protection; Fire-protection; Equipment-design; Underground-mining; Safety-equipment;
Proceedings of the 27th International Conference of Safety in Mines Research Institutes, February 20-22, 1997, New Delhi; Oxford and IBH Publishing Co. Pvt. Ltd., New Delhi, 1997