Methane gas and/or coal dust explosions that have been extensively documented in the past forty years have established, beyond doubt, that methane gas is one of the biggest safety hazards in coal mines. As you would expect, by now, with this information, coal mines should be adequately prepared to prevent and control risks associated with mine explosions. However, the biggest concern is the effectiveness of the measures. Worryingly, many of the measures used are under the control of man, which creates huge margin for error.
There is no other option in effectively managing the hazards of a methane explosion in coal mines apart from using effective explosion suppression solutions, Arend Spaeth, Chief Executive Officer of ExploSpot Systems (Pty) Ltd., reasons African Mining Brief. “When it comes to the safety of employees in underground environment there should be no compromises. You can’t take chances with people’s lives.”
EXPLOSPOT® Automatic Fire and Explosion Suppression System
Beyond question, as explosions occur rapidly, suppression products should be able react instantly. “An explosion occurs in a millisecond and, accordingly, companies should be able to react rapidly. Otherwise, a minor delay can result in loss of assets and people’s lives,’ cautions Spaeth, informing coal mines in Southern Africa about EXPLOSPOT® Automatic Fire and Explosion Suppression System, an active barrier solution for harshest environments.
Spaeth demonstrates how EXPLOSPOT® works, “Once an explosion is ignited, detected and suppressed instantly, full barrier is created, lives and invaluable assets are saved.”
Locally designed and manufactured to high standards, EXPLOSPOT® systems tick all the boxes in terms of safety requirements for explosion mitigation in mines. Mainly, Spaeth underscores the following standards designed for continuous miner installed systems:
- Designed to meet the requirements of the European, Chinese and South African flameproof and performance standards, IEC 60079-0-1 and IEC 61000-6-4 respectively. In addition, EMC according to EN 61000-6-3 and 61000-6-4
- Flame propagation limited to save operator
- Pressure shock within human tolerance
- Temperature within human tolerance
- False alarm immunity
- Re-operable within 8 hours
These systems therefore meet requirement sets out in the DMR directive (D. Mzisa 2003), with respect to autodetecting and suppressing flames resulting from frictional ignitions in burnt coal.
Independent and self-contained, EXPLOSPOT® systems automatically detect explosions and react rapidly. With EXPLOSPOT®, the safe working area is from the face, flame propagation is limited to approximately seven metres. EXPLOSPOT® systems can be deployed in the following areas: Long wall installations, roadway barriers, and mounted on machines such as continuous miners. These installations are installed through a special agreements with original equipment manufacturers (OEMs) and the requirements determined by a mine.
ExploSpot Systems Pty Ltd. also provides preventative monitoring, warning and fire protection specific to conveyors, transformers and switch cabinets.
EXPLOSPOT® systems have the following safety-enhancing features:
- Reacts upon positive explosion within three metres (18” fire)
- 60 degrees angle of view and self-cleaning mechanism
- Fully functional in a dust environment
- With a self-check function, it provides continuous monitoring of the system
- Display components status and Potential-free relay output (machine trip).
Success and new markets
Ever since thorough testing at a well-resourced research centre, EXPLOSPOT® systems, which have been installed on continuous miners, have successfully suppressed over five major methane gas explosions in South African coal mines between 2002 and 2015. Buoyed by growing success in the country, the region and overseas, is eager to expand its scope into other coal mining markets.