RISK ASSESSMENT OF GEOLOGICAL CONDITIONS FOR SELECTIVE EXTRACTION OF OIL SHALE IN ESTONIA MINE

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RISK ASSESSMENT OF GEOLOGICAL CONDITIONS FOR
SELECTIVE EXTRACTION OF OIL SHALE IN ESTONIA
MINE

• S. Sabanov J.-R. Pastarus
• Tallinn University of Technology, Department of
  Mining, Estonia
• O. Nikitin A. Viil
• Estonian Oil Shale Mining Company, AS Eesti
  Põlevkivi, Department of Development, Estonia

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Objectives

• The aim of the study is to determine aspects of
  selective extraction which suit for geological
  conditions in Estonia mine
• The results will be use for other mines according
  with geological conditions and supplying
  technology

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Schematic geologicalsection of the oil shale bed
in mining block 3104 Estonia mine
Immediate roof
Depth of excavation H63 m Extraction thickness h
2.8 and 3.8 m Compressive strength oil shale
20 40 MPa limestone 40 80 MPa Volume
density oil shale 1.5 1.8 Mg/m3 limestone 2.2
2.6 Mg/m3
Commercial oil-shale bed
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Selective mining
Go to backfill 79 of limestone
IV
Go to backfill 63 of limestone
III
II
Go to backfill 86 of limestone
I
B C 13 limestone
Extraction 2
A B C limestone 27
A A1 52 limestone
Extraction 1
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Limestone from seams goes to enrichment
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For all geological condition and all type of
roadheaders
(Roaheader application in mining and tunneling
industries H. Copur, L. Ozdemir, J. Rostami)
UCS Uniaxial compressive strength, ICR-
Instantaneous cutting rate
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Event tree for variant 1 of selective extraction
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Event tree for variant 2 of selective extraction
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Conclusions

• Selective extraction allows reduction of rock
  mass volumes during the loading, transportation
  and enrichment processes. Thus, about 25 of the
  limestone accompanying the extracting processes
  will be left in the mine for backfill in the
  excavated areas. Such a way of development will
  considerably reduce storing of rock waste on the
  ground surface and decrease harmful influence on
  the environment.
• Preliminary calculations have shown
  sustainability of selective extraction for the
  room and pillars method under the geological
  condition of Estonia mine

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• THANK YOU FOR
• YOUR ATTENTION