Grosvenor Inquiry Submission. Cementitious Grout. The April 2020 Incident in MG 104 Pre-Driven Recovery Road that generated Ethylene, be subject to full Independent Investigation and Review.
Cementitious Grout Exothermic Reaction LW 104 Pre Driven Recovery Road
GROSVENOR INQUIRY SUBMISSION. RECOMMENDATION CEMENTITIOUS GROUT USE
The April 2020 Incident in MG 104 Pre-Driven Recovery Road that generated Ethylene, be subject to full Independent Investigation and Review.
The Sean Muller (SIMTARS) “Assessment of Gas Chromatographic Data; part of Inspectorate Investigation M20-0007 Grosvenor Explosion” mention the Grosvenor Mine detected Ethylene in the LW 104 Recovery Road on the 21st April 2020.
This is the only place I can locate in the 96-page Report, that directly links a chemical exothermic reaction causing coal to heat sufficiently to cause the production of Ethylene.
There is no indication whether this grout was used on the LW104 extracted block or the face at any stage.
The sample was then re-analyzed a further Six times to presumably confirm the results.
The results for these samples appeared to not be saved into the LW104 or Surface Gas Well SPW files.
The Report states that the Pre-Driven Recovery has been backfilled with a cementitious grout, causing an exothermic reaction and heated the surrounding coal.
On the 1st of May the Grosvenor Ventilation Officer made the following Ventilation change for the LW104 Pre-Driven Recovery Road. (Presumably when the assessed the Heating was no longer active).
MG 103 1 c/t Dogleg changed from 38.6 to 40.5m3/s
104 X Drive Chute Road 2 changed from 28.5 to 35.6m3/s
Model shows 6m3/s drop to LW Return
2.4.10 MG Compartment – Pre-driven Recovery Road 13
During the processing of the data the following observations where made:
- On the 21st of April, a sample taken on the 19th of April was run for this location. The operator integrated ethylene, which resulted in the sample being repeated another 6 times, presumably to confirm the results. The Graham’s ratio was approx. 0.58 with approx. 127ppm CO.
The results for these samples appeared to not be saved into the LW104 or Surface Gas Well SPW files.
- It is understood that this roadway had been /was being back filled with grout which has an exothermic reaction and would have heated up the surrounding coal.
