Modelling of Gob Inertization with Nitrogen

The paper deals with a modelling of nitrogen distribution throughout gob so that the effect of inertization could be measured. The model takes into account flow transient character, methane liberation and different locations for nitrogen injection. Computer modelling, reflecting mathematical models is done by a specially created computer programme NITRO_ GOB, which allows dealing with different parameters of air leakage, of coal waste distribution as well as of gas picture in the gob before inertization. Effective evaluation of the most important parameters - injection place and nitrogen volume- on gob gas picture is illustrated under typical cross-section profiles of gas concentrations in gob depth and also under oxygen reduction in hazardous zones throughout gob surface. Thus the two aerodynamically linked parameters for object inertization control - place of injection and nitrogen amounts, can be studied. As a result of modeling, some changes in injection technology are suggested, leading to improvement of nitrogen distribution in SPONCOM hazard zones