Underground » Ventilation, Gas Drainage and Monitoring
Underground gassy coal mines both throughout the world and in Australia, often experience periods of high gas emission or weekend-holiday breakdowns, in which the best option is to shut down production, clear out the area and wait for the gas to subside, resulting in costly delays and upset schedules. Most importantly, however, is the necessity to control the gas drainage system under various hazardous conditions such as, underground fires, explosions, dangerous gas concentrations in the captured gas, gas pipeline leakage, or breakdown in the underground power supply or ventilation system continuity.
A solution to this problem has long been the subject of research and development within the industry. Lunagas, has successfully designed and developed an automatic shut down valve prototype for gas drainage networks operating under suction conditions.
The system involves the use of a membrane operating valve and push-spring assembly, joined to the drainage line through an internal by-pass connection. The device will immediately shut down gas flow from individual gas sources or drainage pipes when suction supplies are suspended, and can be reopened automatically, following the reapplication of suction to the drainage line or on gas sources.
The project was aimed at identifying and utilising current technological equipment for the prototype to be designed for Australian underground coal mine conditions. As a result, the prototype of an 80mm diameter valve was designed, manufactured and tested, both under laboratory-workshop and underground conditions.
This report details the equipment and technology successfully employed for 80mm diameter Automatic Shut Down Valve (ASDV) to now be used for commercialised product construction and manufacture for Australian underground coal mines.