Managing Extreme Risk by preventing flammable gas explosions Michael van Niekerk
Eliminating methane explosion risk ExploSpot eliminates the risk of methane explosions by stopping the explosion before it develops It is a permanent sentinel able to detect and react to a methane combustion within 3 milliseconds ExploSpot extinguishes an ignition within 100 milliseconds, by creating a complete barrier and extinguishing the source ExploSpot prevents lethal overpressures (414-552 kpa) and temperatures (100 C > 0.5s) from being reached, as well as toxic gas build up from occurring.
How ExploSpot works Armed mode System always ready Self check BITE (Built In Test Equipment) Detector auto water flush system Event Flame detected and verified < 3 milliseconds Valves open < 5 milliseconds Extinguishant released from nozzles < 10 milliseconds Barrier formed < 100 milliseconds Barrier sustained for 4 seconds Events logged: detector activated, valves opened, pressure released Optional cutter trip
Typical explosion pressure wave
Current ExploSpot Deployment South Africa Collieries (17 systems) Sasol Syferfontein Sasol Middelbult Sasol Middelbult West Sasol ithembulethu Sasol Brandspruit Anglo New Denmark Major China Collieries (400 roadway, 28 long wall, 27 roadheaders, 328 methane pump stations) Daning, Shanxi Gaoping Tangan, Shanxi Tiefa, Liaoning Dongfeng, Heilongjiang Datong, Shanxi
SA 5 confirmed events ExploSpot History Okhozini (2002), Syferfontein (2003, 2005, 2010), Arnot (2005)
Ex / IS / MA Certification The ExploSpot System is designed to comply all the relevant Ex approvals such as: IEC 60079-11:1999 and SANS/IEC 60079-0:2005 for IS equipment IEC 60079-0:2005 and IEC 60079-1:2005 for flameproof equipment South Africa SAEx China CMEx MA Spain GEN
ExploSpot application ExploSpot equipment is approved for: Machine mounted systems (CM or Roadheaders) Long wall mining operations, and Standalone (fixed or mobile) roadway barriers Gas pumping stations & gas pipelines Underground substations switchgear & bus bar protection Bulk fuel storage Surface mining vehicles
CSIR Klopperbos explosion tests CSIR Mining Technology SIMRAC HS Design Engineering CJ Moolman, CSIR Mining Technology (Feb 2005) Project No.: SIM 02 04 03
Unsuppressed explosion
Unsuppressed explosion
Unsuppressed explosion
ExploSpot suppressed explosion
Suppressed explosion
3 millisecond reaction time
Suppressed explosion
Klopperbos 20m Test tunnel
DEG CENTIGRADE Unsuppressed temperature intensity TEMPERATURE AT OPERATOR 600 500 400 300 200 100 0 0 200 400 600 800 1000 1200 1400 1600 1800 2000 TIME IN MILLI-SECONDS
DEG CENTIGRADE Suppressed temperature intensity TEMPERATURE AT OPERATOR 90 80 70 60 50 40 30 20 10 0 0 200 400 600 800 1000 1200 1400 1600 1800 2000 TIME IN MILLI-SECONDS
Roadway gas ignitions
Speed in m/s Unsuppressed explosion: Flame speed Speed Graph for a standard unsuppressed explosion 250 200 150 100 50 0 0 50 100 150 Distance in meters
Passive Roadway Safety Passive stone dust or water trough barriers require a shockwave to activate
Stone dust bag test results 100m reached in <1.0 s 180m reached in <1.5s Temp > 500 C sustained Pressure > 400kPa
Stone dust bags: Flame speed
ExploSpot Active Roadway Barrier
SPEED (m/s) ExploSpot Suppressed Explosion at 30m SPEED GRAPH TEST 99 200 180 160 140 120 100 80 60 40 20 0 0 50 100 150 200 DISTANCE IN METERS ExploSpot eliminates the unsafe work area so that it is safe to work up to the workface ExploSpot eliminates the build up of toxic gasses, pressure and temperature build up
Comparison of active & passive barriers
Longwall shipping container Longwall Solution
Longwall Workshop Installation
Longwall Underground Installation
Longwall Underground Installation
Longwall Operational Underground
Flammable Gas Pipelines
Pipeline system Detector collar Nozzle array Cylinders
ExploSpot CM components Detectors Control box Cylinders Nozzles Wiring Piping
Angle of view and barrier closure
Detector layout on bridge JoyGlobal B / C layout Control box
Cylinder Fitment in bumpers Nozzle layout Spray pattern
Joy AAA Layout
Non-optimal integration
Roadheader total integration with cooperation from OEM
Space optimisation Integrated cylinders Integrated nozzles and detectors
ExploSpot Maintenance To comply with SANS 1475 (servicing fire extinguishers) and due to the highly corrosive environment and rough operating conditions ExploSpot requires the following strict maintenance program: Daily pre-shift inspection CM operator Weekly inspections ExploSpot Field Technician Monthly service ExploSpot Field Technician Quarterly service - ExploSpot Field Technician Annual service - ExploSpot Field Technician
Impact of a lack of servicing
Risk assessments Initial risks controls suggestions = Remaining risk
Thank you Questions? Michael van Niekerk 083 779 1701 michael.vanniekerk@hsd-explospot.com