Machine ventilation and face gas emission
Methane at high purity is released in the cutting zone of the coal face shearer and at some stage during dilution must pass through the explosive range. The ignition hazard can be minimised by diluting the methane rapidly with a large volume of fresh air introduced by a machine ventilation device such as the extraction drum. A method for predicting gas flows and concentrations in the vicinity of the coal cutting machine has been developed which takes account of gas release in the cutting zone together with intake pollution at the machine, arising from a variety of sources. Effects of changing advance rate can be predicted. The method has been successfully tested for machines with cowls and for faces working high-volatile rank coals; further work is needed to permit broader application. A detailed study has been made of the ventilation characteristics of the extraction drum. The scale modelling technique employed a combination of similarity parameters. Once validated by comparison with full-scale results, the model enabled radical design alterations to the extraction drum to be studied both rapidly and at low cost.
Bibliographic Reference: EUR 13585 EN (1991) 92 pp., MF, ECU 4, blow-up copy ECU 12.50
Record Number: 199111039 / Last updated on: 1994-12-02
Original language: en
Available languages: en