Application of nozzles and jet pumps supplied with compressed air for methane high concentration fighting in mining workings

摘要

Relationships for ventilation capacity and air velocity calculation at the outlet of jet pumps equipped with Laval nozzles supplied with compressed air are presented. Examples of air jet pumps UW and SUW type use on the crossing of longwall and ventilating roadway for methane hazard fighting are given and next the principles of jet pumps selection depending on absolute methane-bearing capacity of longwall goal are discussed. Computational examples are given.