Grosvenor Mine video camera recordings sequence of events does not show an overpressure event in the goaf. Maingate Brattice Wing is Sucked In First. How does that fit with Pet Theory of overpressure from goaf fall?
There is mention of recorded camera footage of the explosion on the Longwall 104 face in Anglo “Learning From Incidents” Investigation Report Incident Number: IN.00224943 into the Methane Ignition on LW 104.
The problem for all those proposing the scenario a major roof fall in the immediate goaf causing a PUR initiated heating to suddenly flare to a temperature of over 540C and ignite methane around 20 seconds later is that the video commentary on the sequence of events does not support this.
There are a few comments I need to make first
Firstly although there is supposed to also be a camera permanently recording in the Tailgate it is never mentioned. I can only assume it was non-operational throughout the relevant time period.
Secondly I assume that the Investigators have been clever enough to run the video recordings of the Maingate and Bretby camera’s simultaneously on a split screen.
Thirdly there is no indication when over the 20 seconds referred to each noted event occurs
The first visible event mentioned is
- Maingate brattice wing pushed into the goaf (as seen on MG camera looking inbye).
If there was a large roof fall in the goaf why is the Maingate brattice wing being pushed (sucked) into the goaf?
If there was a large fall causing an overpressure event then the Maingate Brattice wing should push out of the goaf, not get sucked in.
This in my view runs in exactly the reverse of everything we have been subjected to at the Grosvenor Inquiry for the last 2 to 3 weeks
2. Increased dust at Shearer (as seen on Bretby Camera).
The Shearer is stopped and parked at #120 roof chock (out of 149).
Where the dust appear from? Does it come from the back of the chocks? or
Does it come from the floor or roof around the shearer or from the shearer?
3. Maingate brattice wing being sucked back away from the goaf (as seen on MG camera looking inbye).
So now goaf atmosphere is being either sucked or pushed out when there is supposed to be suck back into the goaf
4. MG brattice wing pushed back into the goaf a second time (as seen on MG camera looking inbye).
5. Dust / pressure wave from TG to MG (as seen on MG camera looking inbye).
So a pressure wave is now coming from the Tailgate towards the Shearer and then the Maingate.
6. Flash near shearer (as seen on Bretby camera).
This is the last event mentioned so I assume this is when power drops off the face and the camera’s lose power and stop transmitting to the surface.
The comments in order and unchanged are
Visible Sequence of Events over an approximate 20 second period (as seen on operational cameras underground):
- Maingate brattice wing pushed into the goaf (as seen on MG camera looking inbye).
- Increased dust at Shearer (as seen on Bretby Camera).
- Maingate brattice wing being sucked back away from the goaf (as seen on MG camera looking inbye).
- MG brattice wing pushed back into the goaf a second time (as seen on MG camera bokhg inbye).
- Dust / pressure wave from TG to MG (as seen on MG camera looking inbye).
- Flash near shearer (as seen on Bretby camera).
As I have mentioned in my previous post
All electrically powered equipment on the Longwall Face has to have power tripped when the methane detectors on the face reach 2.5%.
If the Maingate, Bretby and I assume the Tailgate Cameras are still powered and recording, there must still be AC high voltage power to the face.
Therefore the methane monitors on the shearer or the Tailgate Drive have not measured 2.5% Methane and tripped the power.
That means that the Shearer, Maingate and Tailgate Drives and Chock Controls are all powered, as other sundry electrical equipment such as Cameras and Methane Sensors
It is all in the timing
I stand by my comments made in a post on the 14th of March
“How on earth can a short duration compression wave (overpressure event) cause a supposed heating right at the back/roof of the chocks around # 111 to flare into open flame above 537C and then after it has ignited the methane, disappears totally?”
“The fact is, it cannot”
Grosvenor PUR Scenario does not make scientific sense. Temperature necessary and products of combustion never detected prior to ignition or in weeks after.
https://www.qldminingcrisis.com.au/2021/03/14/grosvenor-pur-scenario-does-not-make-scientific-sense-temperature-necessary-and-products-of-combustion-never-detected-prior-to-ignition-or-in-weeks-after/
I have also added link addresses to previous posts in order of date
PUR Injection in Underground Coal Mines Safety Alert. Are we seeing the Mines Department (RSHQ) most likely cause of the Grosvenor Mine Disaster for the first time.
https://www.qldminingcrisis.com.au/2021/02/25/pur-injection-in-underground-coal-mines-safety-alert-are-we-seeing-the-mines-department-rshq-most-likely-cause-of-the-grosvenor-mine-disaster-for-the-first-time/
PUR Driven Spontaneous Combustion Event. The new Flame Safety Lamp for 2021? How soon till we hear “This has Industry Wide Implications”?
https://www.qldminingcrisis.com.au/2021/03/14/grosvenor-pur-scenario-does-not-make-scientific-sense-temperature-necessary-and-products-of-combustion-never-detected-prior-to-ignition-or-in-weeks-after/
Heat Affected Coal Spontaneous Combustion Propensity. Grosvenor Mining Inquiry Findings already Ordained?
https://www.qldminingcrisis.com.au/2021/03/20/heat-affected-coal-spontaneous-combustion-propensity-grosvenor-mining-inquiry-findings-already-ordained/
Why this Ad-Nauseum attention to PUR as a contributor to a methane ignition on the Longwall Face at the Grosvenor Inquiry? What about other just as, or more likely Ignition Sources?
https://www.qldminingcrisis.com.au/2021/03/21/why-this-ad-nauseum-attention-to-pur-as-a-contributor-to-a-methane-ignition-on-the-longwall-face-at-the-grosvenor-inquiry-what-about-other-just-as-or-more-likely-ignition-sources/
