longwall mining in western pennsylvania - pittsburgh post...
TRANSCRIPT
Enlarged area
High-Quality
N
Waynesburg
1940
19
88
88
51
51
Enlow Fork
Shoemaker
Shoemaker
Balley
Eighty-four
Dilworth
Emerald
Blacksville #2
Cumberland
Washington
Bridgeville
W A S H I N G T O N
A L L E G H E N Y
G R E E N E
Gastonville
Bentleyville
Masontown
79
79
70 70
40
MapleCreek
High-Quality
Westland
Vesta
Gateway
Warwick
Humphrey #7
Blacksville #1
Canonsburg
Ground level
Mine floor
Pillarsof coal
Steel shields to protect the miners fromthe loose rocks aboveand behind.
Shearer
Conveyor belt
Raw coal
Machineoperator
“Panel” of coal to be mined using thelongwall technique.The area can range from 800 to 1,500 feetwide and up to 3 miles long.
Elevator/ventilation shaft(exhaust fan helps air flow)
Steve Thomas/Post-Gazette
Intake air
Ret
urn
air
Source: Consol
Longwall mining in Western Pennsylvania
Subsidence in which the overlying rock and other materialfalls into the void where coal has been removed resultsfrom longwall mining. As the longwall system advances,the mine roof caves in behind the steel shields.
G : graphic : Science : July2003 : Longwall Mining : “longwall_mining.FH9”
Pillars are in the “mains” developmentpart of the mine. The coal is removedthrough those passages and goodair/bad air is exchanged, also minerstravel through those passages.
Steel shields to protect the miners fromthe loose rocks aboveand behind.
Active and closed minesSubsidence
In longwall mining, a very large block or “panel” ofcoal is isolated by the development of entries andcrosscuts. Special mining and roof support equipmentis then set up along the working face. This working facecan be anywhere from 800 to 1,500 feet wide.
The coal is mined by a longwall mining machine thatmoves across the face. Mined coal is then hauled by achain conveyor along the length of the face. The roof issupported by special hydraulic supports called chocksand shields that are advanced as the mining progresses.
An ‘under’ view
Active Closed
RAG:• Cumberland Mine• Emerald Mine
Consol• Bailey Mine• Blacksville No. 1• Dilworth• Eighty-Four Mine• Enlow Fork Mine• Humphrey No. 7• Vesta:
Originally J&L Steel,then A.T. Massey Coal.
• Westland
Maple CreekMining, Inc.• High Quality Mine
Consol (WV)• Blacksville #2• Shoemaker
Duquesne Light Co.• Warwick No. 3
Gateway Coal Co.• Gateway
Coal
Mine floor
Ground level