This document provides an overview of open pit mining technologies used in coal mines operated by SCCL in India. It discusses the key types of surface and subsurface mining methods. For open pit mining, it describes various mechanized methods used including shovel-dumper combinations, draglines, and bucket wheel excavators. It also outlines the ideal conditions for open pit mining and discusses operations involving stripping, drilling, blasting, extraction, and transport of coal. Pit design considerations like bench dimensions and slope angles are also summarized.

1. PRESENTATION
ON
Different Technologies in OC mines of SCCL
I. Satyanarayana, M.Tech,MBA,MCA
Dy. Manager, Project Planning, SCCL,
isnindian@gmail.com,
visit at www.slideshare.com/isnindian
ISN 1

2. Every newly born will need….
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3. • Mining is extracting
ore or minerals from
the ground
• An ore is a natural
material with a high
concentration of
economically
valuable minerals that
can be mined for a
profit
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4. • There are two main types of mining.
1) Surface Mining
2) Subsurface Mining
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5. Mining Methods (Mode of Entry)
Shaft Mine Incline Mine
Incline
Excavator
Adit Mine Opencast Mine
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6. MINING METHODS
COAL MINING
METHODS
UNDER GROUND OPENCAST SPECIAL MINING
Methods Methods Methods
Hydraulic
Gassification
Mining
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7. What is Opencast Mining
• Opencast mining is also known as Open pit mining, Open cut
Mining, Surface or Strip Mining.
• The coal upto economical depth will be excavated by OC Method.
• The overburden and the Coal are excavated in long strips of a few
meters thickness.
ISN 7

8. SURFACE MINING
• Based on System of Mining
– Continuous & Discontinuous
• Based on Mechansiation
– Manual & Mechanised
• Based on method and nature of mining:
1. Open-pit: Reclamation after completion
2. Open-Cast: Reclamation during mining
3. Quarries: stone, crushed rock, sand, gravel
4. Strip Mining: removing surface coal in strips up to 50 m
wide x 1 Km long
5. Placer Mining
6. Glory hole Mining
ISN 8

9. MECHANISED OPENCAST METHODS
OPENCAST
Methods
SHOVEL DUMPER SHOVEL DUMPER Inpit Crussing SURFACE BUCKET WHEEL HIGH WALL
COMBINATION Combination and MINER EXCAVATOR MINING
with Conveyor
DRAGLINE Technology
ISN 9

10. Ideal conditions (Suitability) for Opencast Mining
1. Thickness of coal seams- > 5m
2. Flat gradient - < 1 in 6
3. Strike length - > 1 km
4. No.of seams - Less the better,
with higher thickness
5. Coal without stone bands
6. Free from surface structures / features.
7. Preferably non-forest land.
8. Availability of adequate place for dumping.
ISN 10
9. Lower Stripping ratio depending on quality of the coal

11. Advantages of opencast mining
There is no problem of ventilation
There is no problem of Roof control, supports
There is no problem of lighting in daytime.
Percentage of coal extraction is much higher (about
90%) than that of Underground mining (30-60%)
High OMS
Much productivity / profits.
Quick returns on capital investment.
Dangers & Hazards are less compare to U/G Mines.
There is no risk of gas explosion.
Large-scale mechanisation is possible.
Gestation period is less
ISN 11

12. Disadvantages of opencast mining
•Work is affected by weather.
•Land degradation by mining.
•Deforestation.
•Pollution( water, Air, Land, Noise ).
•The method is uneconomic for workings
Deeper Depths, cities and under sea/rivers.
•The quarried area and OB dump heaps
present an unpleasant sight.
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13. TERMINOLOGY
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14. STRIPPING RATIO
AMOUNT OF OVERBURDEN REMOVED IN MINING A UNIT OF
MINERAL
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15. OPEN PIT MINE
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16. OPERATIONS IN OPM
• LEVELLING BY DOZING
• DRILLING.
• BLASTING
• REMOVAL OF OVERBURDEN
• DUMPING, BACK FILLING,
RECLAMATION
• EXTRACTION OF COAL
• TRANSPORTING to (CHP, CSP, FLOOD
LOADING SYSTEM, Rapid loading etc.,)
ISN 16

17. OPERATIONS IN OPM
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18. Development Sequence
Opening the deposit – Access trench
Box cut - To accommodate all equipment
Mine phases - Depends on the shape of the property
Progress of Benches
Coal production schedules
OB excavation schedules
Note:- Maximize inventory of coal in the initial years
• Differ OB stripping requirements as much as possible – Average
SR versus natural SR
• Income generated in the first 5 to 10 years but not remote economics
will either make or break the project.
• Profits for in the future have practically no impact on the project NPV.
Each successive phase will be less profitable and the ultimate
limit will be loss even after ploughing in profits earlier.
ISN 18

19. ISN 19

20. FOREST LAND NON FOREST LAND
SURFACE
COAL
SEAM
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21. END OF STAGE -1
FOREST LAND NON FOREST LAND
EXTERNAL
DUMP YARD SURFACE
COAL
SEAM
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22. END OF STAGE -2
FOREST LAND NON FOREST LAND
EXTERNAL
DUMP YARD SURFACE
INTERNAL DUMP
COAL
SEAM
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23. END OF STAGE -3
FOREST LAND NON FOREST LAND
EXTERNAL
DUMP YARD SURFACE
INTERNAL DUMP
COAL
SEAM
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24. FINAL STAGE
FOREST LAND NON FOREST LAND
EXTERNAL
DUMP YARD SURFACE
INTERNAL DUMP
COAL
SEAM
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25. MINE CLOSURE STAGE
FOREST LAND NON FOREST LAND
RECLAMATION UPTO
45 m BELOW GL SURFACE
INTERNAL DUMP
COAL
SEAM
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26. Pit design
As per Regulation 98 of CMR 1957,
In alluvial soil etc. - Sides shall be sloped at 450 or
Benched – height not more than 1.5m
Width – not less than height
In hard ground - Sides adequately benched/sloped so as
to prevent danger from fall of sides
Coal - Sides shall be sloped at 450 or
Benched – height not more than 3m
However, exemption can be sought from Inspectorate.
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27. Pit design
Overall slope of a pit depends on several factors of the pit slope:
a) Geological disturbances like faults etc.
b) Hydrological condition of strata
c) Orientation of slip planes
d) Nature of strata – i.e. hardness, material consolidation etc.
e) Depth of workings
f) Design of haul roads & ramps in the highwall
g) Stratigraphy – thickness, spacing of the clay bands or other weak
layers
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28. Pit design
In general for OC mines upto a depth of 200m, overall slope angle of 450 is
permitted.
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29. Pit design
For deeper mines flatter highwall slopes will be necessary from safety point of
view (for 35 T dumpers & above)
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30. Pit design
Working benches
1) General
Width - 40 – 45m
Height - Generally equal to height of the boom or in some cases
upto 3m above the boom height.
In case of Backhoe – digging height of machine
Bench slope - 560 to 700
2) Dragline:
Width of the cut - 60m
Height of bench - maximum digging depth
3) In order to even out the yearly OB removal quantities and the
economics, sometimes alternative working and non-working benches
(around 25 m wide) are proposed.
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31. OPEN PIT MINING Operations
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Source: WCI 2005

32. ISN 32

33. Different Technologies in OC Mines
1) Shovel Dumper technology.
2) Dragline technology
3) Inpit Crusher – conveyor – spreader – technology.
4) Continuous Mining technology – Bucket wheel excavators.
5) Rock Breaker technology.
6) Surface Miner technology.
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34. Auxiliary mining equipment
Other common mining equipment to all the technologies
•Drills
•Dozers ,Graders & Compactors
•Water Sprinklers
•Pumps etc
•Electrical equipment
•Crushers & Conveyors for Coal/OB
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35. Our Technology - Opencast
Technology
•Dragline
•Shovel & Dumper
•Surface Miner
•Inpit crushing – Conveying –
Spreading
•Highwall
Operational Profile
•14 OC Mines
•Coal: 39.72 MT OB: 214.47 MCu M
• Avg.Stripping Ratio: 1:6.5
•Gradients operated : upto 19°
•Depths operated: 220 Mts.
•Depths Planned: 420 Mts.
ISN 35

36. SCCL OC Mines – Technology wise
1. Drag Line-Shovel & Dumper combination
– RG OC I Expansion
– RG OC III Extension
2. Inpit Crusher & Conveyor Technology
– RG OC II Extension
– GK OC
3. Surface Miner Technology
– Koyagudem OC II
• Remaining all other OC projects in SCCL are being
operated with Shovel Dumper Combination
• High Wall mining Technology is now being practiced in
ISN 36
RG OC II Extension project.

37. Comparison of SCCL with CIL
No of Mines Production (MT)
Parameter OB(M.cum) Avg.STRIPPING
RATIO
UG OC Total UG OC Total
SCCL 36 14 50 11.61 39.72 51.33 214.47 1 IN 6.5
CIL 299 174 473 54.56 376.76 431.32 695.27 1 IN 3.0
When Compared with CIL, SCCL’s Constraints are :
• Limited Opencastable reserves.
• Reserves are deep seated (300 to 600m).
• Low grade Coal
• Highly Geologically Disturbed
• Thin Seams
• High Stripping Ratio
• Steep Seams
• High Cost of Production
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38. Technology-wise Cost Vs Sale Value
As on Feb’2011
Cost Of Avg. Sales
Profit/Loss
Technology Prodn Reliazation
(Rs./T)
(Rs./T) (Rs./T)
Hand Section 4032 -2475
Load Haul Dumpers 2250 -693
Side Discharge Loaders 1859 -302
Longwall 1080 477
Road Header 4870 1557 -3313
Blasting Gallery 1794 -237
Continuous Miner 1562 -5
Overall SCCL (UG) 2323 -766
Overall SCCL (OC) 1036 521
Overall SCCL 1404 153
The Singareni Collieries Company Limited(A Govt. Company)
ISN 38

39. Contd…
OC Vs UG PRODUCTION
Year OC UG TOTAL OC % UG %
2010-11 39.72 11.60 51.33 77.38 22.60
2009-10 38.45 11.96 50.42 76.26 23.72
2008-09 32.35 12.08 44.44 72.79 27.18
2007-08 27.95 12.64 40.60 68.84 31.13
2006-07 25.83 11.87 37.70 68.51 31.49
The Singareni Collieries Company Limited(A Govt. Company)
ISN 39

40. UG Vs OC PERFOMANCE
OC UG
PAT
Year Cost Sale Value Profit/Loss Cost Sale Value Profit/Loss
(Cr)
(Rs/T) (Rs/T) (Rs/T) (Rs/T) (Rs/T) (Rs/T)
2010-11 Around
1036 1557 521 2323 1557 -766
(Upto Feb) 350
2009-10 1011.83 1296.48 285 2169.48 1628.77 -541 268.01
2008-09 802.71 1225.98 423 2037.75 1490.07 -548 132.83
2007-08 703.75 1100.13 396 1714.05 1191.00 -523 176.17
2006-07 635.63 1005.67 370 1797.81 1065.93 -732 63.80
The Singareni Collieries Company Limited(A Govt. Company)
ISN 40

41. UG-OC COST & SALE VALUE
In Crores
OC
Year OC % UG % UG LOSS
PROFIT
2010-11 77.38 22.60 1497.10 461.83
2009-10 76.26 23.72 1114.17 633.44
2008-09 72.79 27.18 1319.49 628.48
The Singareni Collieries Company Limited(A Govt. Company)
ISN 41

42. Maintenance of OC to UG ratio is Essential for
Sustenance of the Company
There is no Budgetary Support from the Govt.
Funds are required for operation of existing
mines and to start new mines.
At Present, The Profit to the Company is on
account of OC Mines by offsetting losses from UG
mines
The Singareni Collieries Company Limited(A Govt. Company)
ISN 42

43. ATTACHMENTS ON A BASIC SHOVEL
ISN 43

44. Mining with SHOVEL – DUMPER combination
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45. 1)Shovel Dumper technology
• This is the most commonly used technology in Opencast mines.
• Basically two variants – Rope shovels and Hydraulic shovels (backhoe)
• Shovel used for excavation & Dumper for transport of material.
• Bucket capacities vary from 0.9 Cum to 40 Cum with matching
Trucks/Dumpers of 16 Cum to more than 240 T.
• Can be deployed for removal of varying thickness of materials.
• Harder materials require blasting.
• Can be deployed for removal of steep & thin seams (hydraulic shovels).
• electrically driven or Diesel operated (shovels)
Selection depends on the parting – wise volumes to be removed.
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46. POWER SHOVEL
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47. Rope shovels:
• Life is large compared to Hydraulic shovels (20 – 25
years).
• Initial capital is high compared to Hydraulic shovels.
• Can work only on mild gradient of around 1 in 10.
• Ideally suited for less no of marchings.
• generators are driven by main motor and individual
DC-motors are provided for different operations like
propel, swing, hoist, crowd etc.,
ISN 47

48. Rope Shovel & Dumper
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49. Rope Shovel & Dumper
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50. Rope Shovel & Dumper
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51. Hydraulic shovels
1. Versatile – easy to march from place to place.
2. Productivity is higher than rope shovels.
3. Can march on steep gradient.
4. Can be deployed for removal of wedge portions in the
last OB bench (over coal seams).
5. Can be used for preparation sumps and drains.
6. Can load on dumper placed at the same level as that of
the shovel (same level loading) or on a dumper placed
below the shovel level.
7. Can be used for removal of soft coal/ strata without
blasting.
8. Can be deployed for removal of thin seams.
9. The life of shovel is around 9 to 12 years only and
requires a mid-life overhaul.
10. Initial capital is low compared to Rope shovels.
11. the operation is through hydraulic motors
ISN 51

52. ISN 52

53. Hydraulic Shovel & Dumper
ISN 53

54. Hydraulic Shovel & Dumper
ISN 54

55. Front-end Loader & Dumper
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56. Dumper
1. After blasting the rock, the muck is loaded into the rear dumpers by shovels.
For a bench height of 12 to 14m, front end rope shovels (Front End Shovels
may be rope shovels or hydraulically operated) of 10 cum and above is
normally used.
2. Various ranges of dumpers of different manufactures are available.
3. The capacity of the dumper depends upon the capacity of the loading
ISN 56
shovel.

57. Operating conditions
• Can be deployed on shot ramps of 1 in 10 & haul roads
of 1 in 16.
• Haul roads of two way traffic are ideal.
• Recommended width for > 35T dumpers including Dozer
path, drains etc is 30m.
• Fewer number of curves with adequate super elevation is
desirable.
• Adequate consolidation of Haul roads , suitable graded &
Water spraying is needed.
• Level platforms to be provided at suitable intervals.
ISN 57

58. DOZER
ISN 58

59. DOZER
ISN 59

60. OPERATION OF DOZER
It is the vital equipment in Open cast mining.
tractor with a pusher blade attached to the front portion.
Diesel operated with crawler chain (some times tyre mounted
Dozers also used)
the pusher blade can be raised lowered or tilted through small
angles horizontally by rams operated by hydraulic pressure.
The Dozer blade is used for pushing loose material, digging earth,
soft weathered rock, for pushing scrapers, for levelling / grading and
compacting the ground, for laying haul roads, for toeing dumpers etc.,
for pushing boulders trees etc.,
There is different capacity of Dozers ranging from 100HP to 800
HP and normally used are 400 HP, which costs app. 1.2 Cr.
ISN 60

61. WHEEL DOZER
1968 CaterpillarISN Wheel Dozer
824 61

62. WHEEL DOZER
tractors outfitted with dozer blades or push blocks.
used as push tractors in scraper applications.
Though these machines can be converted from wheel
loaders by replacing the loader’s bucket with a dozer blade,
this configuration is only successful for light-duty tasks.
Used for clearing and grading land, wheel dozers are
frequently used in mining applications and reclamation jobs.
The wheel dozers’ advantage over crawler dozers is their
ability to move quickly.
Additionally, they can travel between multiple job sites
without damaging paved roads.
ISN 62

63. RIPPER DOZER
ISN 63

64. RIPPER DOZER
ISN 64

65. RIPPER DOZER
tractors outfitted with dozer blades or push blocks.
A Dozer equipped with fork like attachment is known as
“Ripper”
can be mounted either with one or two rippers
operates like a plough to loosen moderately hard rock
can be also used to extract thin seams where the
thickness is less than 1.2 m where blasting is not effectively
done.
It rippes the thin seams and later can be loaded by the
Shovel & Dumper combination.
There are other crane attachments for the Dozer which is
known as pipe layer for transporting pumps, pipes and
laying pipes.
ISN 65

66. MOTOR GRADER
ISN 66

67. MOTOR GRADER
ISN 67

68. MOTOR GRADER
tractors outfitted with dozer blades or push blocks.
This is a machine used for levelling the road surface by
smoothening out the ups and downs and for casting aside
the boulders on the road.
It is always pneumatic tyre operated with rear wheels
drive.
The grading blade is attached to a circle that is hung from
the overhead frame and pulled by a drawbar fastened to the
front of the frame.
The blade is usually 3 to 4m long having replaceable
edges on the sides and bottom.
The approximate cost of a medium size Motor Grader will
be Rs 60 Lakhs.
This is essential equipment in Opencast mining for
ISN
continuous maintenance of haul roads. 68

69. SCRAPER
• excavation cum transport equipment
• suitable for soft material
• generally used for top soil removal
• Diesel operated with pneumatic tyre wheels
• a bowl fitted with a cuttingISN
blade at the bottom. 69

70. OPERATION OF SCRAPER
A scraper is pushed forward by a Dozer
It’s blade cuts a thin slice of a earth usually between 100 mm to 250
mm thick over a distance of nearly 30 m.
The earth is automatically collected in the bowl located at the centre
of the machine.
The bowl capacity ranges from 5 cum to 20 cum and takes nearly half
to one minute for loading.
When the scraper is fully loaded its bottom opening is closed through
a table operated by the operator.
At the dumping yard as the Scraper moves, the bottom opening of
bowl is opened, and the contentsISN earth are unloaded in the layer
of 70
150 mm to 250 mm thick over a distance of 30 to 50 m.

71. FRONT END LOADER
Wheel-loader (also known as Pay loader or Front-end Loader) for
loading dumper or tipping truck for transport
ISN 71

72. FRONT END LOADER
ISN 72

73. FRONT END LOADER
These loaders are a popular addition to tractors from 50 to 200 hp.
A loader (also known as: bucket loader, front loader, front end
loader, payloader, scoop loader, shovel, skip loader, and/or wheel
loader) is a type of tractor, usually wheeled, sometimes on tracks, that
has a front mounted square wide bucket connected to the end of two
booms (arms) to scoop up loose material from the ground, such as
dirt, sand or gravel, and move it from one place to another without
pushing the material across.
A loader is commonly used to move a stockpiled material from
ground level and deposit it into an awaiting dump truck or into an open
trench excavation.
The loader assembly may be a removable attachment or
permanently mounted. Often the bucket can be replaced with other
devices or tools—for example, many can mount forks to lift heavy
pallets or shipping containers, and a hydraulically-opening "clamshell"
bucket allows a loader to act as a light dozer or scraper.
ISN 73

74. 2. DRAGLINE WORKING
ISN 74

75. Dragline Working
ISN 75

76. DRAGLINE
• Draglines are deployed wherever there is scope for
side casting Overburden above coal seam into the
de-coaled area.
• It is very cost effective technology- cost of OB
removal is cheaper than shovel dumper
technology.
• There are two draglines working at RGOC-I and
RG OC-III with bucket size of 24 Cum and 30.6
Cum respectively.
• Both these draglines are performing very well.
• A dragline bucket system consists of a large bucket
which is suspended from a boom with wire ropes.
• The bucket is maneuvered by means of a number
of ropes and chains.
ISN 76

77. OPERATION OF DRAGLINE
In a typical cycle of excavation, the bucket is positioned
above the material to be excavated.
The bucket is then lowered and the dragrope is then drawn so
that the bucket is dragged along the surface of the material.
The bucket is then lifted by using the hoist rope.
A swing operation is then performed to move the bucket to
the place where the material is to be dumped.
The dragrope is then released causing the bucket to tilt and
empty. This is called a dump operation.
It is a independent machine unlike a shovel.
A 30 cum Dragline can handle 40 Lakh cum of OB per annum.
The dragline works on the immediate OB bench above coal
and the benches from the surface to the Dragline are normally
handled by Shovel & Dumper combination. Hence adequate
capacity of Shovel & Dumper ISN capacity should be provided to
77
prevent idling of the Dragline.

78. OPERATION OF DRAGLINE
The Dragline has a long boom with a bucket capacity ranging
from 15 to 50 cum.
It can swing in 360 degrees, after dragging the loose material
below its level.
It swings normally between 90 to 120 degrees and side cast
the material in to the de-coaled area.
The nomenclature of the Dragline usually called as 24/99
which means 24 cum of bucket capacity and 96 m is the boom
length.
The same Dragline can have about 32 cum of bucket capacity
if the boom length of 71 m. normally
The Draglines are electrically driven with 6.6 KV power with 2
main motors of 1750 HP each. These motors in turn drive the
Generators and the Generators drive DC motors
Normally, there are 7 DC motors for different operations like
ISN
marching, dragging, hoisting, swinging etc., 78

79. DRAGLINE BUCKET
ISN 79

80. LINE DIAGRAM OF DRAGLINE
ISN 80

81. LINE DIAGRAM OF DRAGLINE
ISN 81

82. APPLICATION OF DRAGLINE
1. Gradients flatter than 1 in 6 (if gradient is more the
dumped OB will slide towards the coal face and
particularly in rainy season the extraction of coal
become dangerous)
2. Seams should be free of faults & other geological
disturbances
3. Deposits with Larger Strike length (>2 km) so that
frequent shifting of the Dragline from one end to
another can be reduced.
4. Present cost of the Dragline is above 100 Cr and the
life of the Dragline is 1.50 Lakh hours hence, the
property should be large enough ensuring the life of
about 25 yr or more.
5. A hilly property is not suitable
6. Property should have atleast 15 years life.
ISN 82

83. ISN 83

84. 3. In pit crusher conveyor technology
•The drilled & blasted OB is loaded by shovels and transported by dumpers
to Crushers. The crushed OB is then transported by a series of conveyors
into a spreader for dumping.
•Can be used in steep seams where laying of transport roads for the trucks
is difficult.
•While S.R indicates volumes, cut off ratio indicates depth and reflects in
dumper haulage cost, which increase with depth and may become
prohibitive where in alternative haulage system may have to thought off.
•Ideally suited where material has to be transported over a longer distance
& high lift.
ISN 84

85. 3.IN-PIT CRUSHER CONVEYOR TECHNOLOGY
• Haulage costs have been an area that have risen significantly with the
increase of diesel prices.
• One alternative to reduce haulage costs is to shorten the truck haul
distance by bringing the dump point into the pit using an in pit movable
crusher/ crushers and conveying the Over burden out of the pit can
reduce the haul cost.
• When the gradient is too steep, dumping the material within the mine is
not practicable as the dumped OB slides on to the coal face. In such
cases in pit crushing is preferred.
• The flow of material utilising an inpit movable crusher and conveyor
system starts with OB material being dumped into crushers by
dumpers. The material is crushed and fed on to horizontal transfer
belts within the pit or directly on to a major up slope belts taking the
material out of the pit. There may be one or more belts depending on
the pit Geometry and depth. The conveyed material is dumped as per
Video
the requirement and the dump design by using spreaders.
ISN 85

86. In pit crusher conveyor technology:
• Can be used in steep seams where laying of transport
roads for the trucks is difficult.
• Ideally suited for large capacity projects.
• Ideally suited where material has to be transported
over a large distance with huge lift.
• Requires huge capital.
• The transport cost will be much less than compared
to shovel dumper combination.
• Requires heavy equipment like crushers, conveyor
distribution point and spreaders.
ISN 86

87. Ramagundam OC-II with Inpit Crushing & Conveying Technology
Depth and gradients makes dumper haulage prohibitive due to high operating
cost. The alternate choice is ICC where material has to be transported over a
large distance & lift.
The drilled & blasted OB is loaded by shovels and transported by dumpers to
Crushers. The crushed OB is then transported by a series of conveyors into a
spreader for dumping.
ISN 87

88. Salient features of RG OC-II Project
No.of seams- 10
Gradient- 1 in 3.6 to 1 in 4
Depth planned- 400m
Capacity of the project- 4 MTPA
Technology- Shovel dumper combination with ICC technology
Life of the project- 27 years
Stripping Ratio- 7.73 Cum/T (107.46 Mt of coal and 808.46 M.Cum of OB)
Grade of the coal- ‘D’
OMS- 6.88 planned
Cost of production in Rs/T - 1606.94
Total Capital outlay of the project is estimated at Rs 896.32
Slope stability is a vital aspect in this project, as final highwalls will have a height
of up to 400 m which need to be planned as steep for better economics.
The 120m high dumps with crushed OB(low cohesion) will pose different
problems in dump stability which needs a comprehensive study on design,
ISN
maintenance, monitoring and stabilisation altogether. 88

89. IN-PIT CRUSHER CONVEYOR
TECHNOLOGY
ISN 89

90. ICC at RG OC-II
ISN 90

91. Ramagundam OC-II Mine with Inpit Crushing & Conveying Technology
Compacted floor sloped 2-3°towards toe of the upper deck to direct the water to the
ISN 91
drain to avoid seepage into the dump. Better we provide lined drains/channels.

92. ISN 92

93. ISN 93

94. The spreader can rotate with an angle of 120 degrees.
In SCCLtd, the inpit crushing and conveying system introduced in RG OC II,
Ramagundam. The capacity of each crusher-conveyor system is 1200
cum/hour. There are 3 such systems in addition to coal conveying system in
ISN 94
RG OC II mine.

95. 4) Continuous Miner Technology:- Bucket Wheel Excavators
•Presently being used in Naveyali, Lignite Opencast mines,
having soft strata.
•The buck wheel excavates the material without blasting
which is transported by a series of belt conveyors to
spreader.
ISN 95

96. 4. BUCKET WHEEL EXCAVATOR(BWE)
ISN 96

97. BUCKET WHEEL EXCAVATOR(BWE)
This machine is suitable for excavating soft and non stickey material in
large quantities.
Lignite deposits usually associated with soft over burden. Most lignite
mines in world use these BWEs for both OB and Lignite, as is the case
this Lignite mines are “Nyveli Lignite Corporation” of India Semi hard
material also be made suitable for BWEs by small blastings.
The BWE is a continuous excavating machine and capable of removing
of OB up to 1200 cum / per hour.
The excavation component of BWE is a large rotating wheel mounted on
an arm/boom.
On the outer edge of wheel is a series of scoops/ buckets as the wheel
turns, the Bucket removes soil
As the wheel turns, the bucket removes OB/Coal from the target areas
and carries it around to be the back side of the wheel, where it falls on to
a conveyor which carries the material to the identified destination.
BWE are generally worked in combination with crusher & conveying
ISN 97
system.

98. ISN 98

99. ISN 99

100. Overview – 3D view
ISN 100

101. METHOD OF MINING
Opencast continuous mining system using
• Bucket Wheel Excavators
• Spreaders
• Conveyor Systems
Refilling Mine Advancing Side
NSBS
NSBS
SBS
SBS
TBS
TBS
Spoil Bank
MBS
MBS OB bench Avg. Height – 25 m
Spoil Bank BBS
Av. Height – 15 m
Spoil Bank BBS Lignite Bench
Maximum Height = 22 m
ISN 101

102. 1400 LITRE BRIDGE TYPE BWE
Rated Production : 2250 m3/hr
Outreach from BW boom to Discharge boom : 130 ± 12 metres
Maximum High Cut height : 30 metres
ISN 102
Service Weight : 3193 Tonnes

103. 1400 LITRE BWE
Rated Production : 2250 m3/hr
Outreach from BW boom to Discharge boom : 61.3 metres
Maximum High Cut height ISN : 26 metres 103
Service Weight : 2170 Tonnes

104. 700 LITRE BWE WITH DEEP CUT FACILITY
Rated Production : 1100 m3/hr
Outreach from BW boom to Discharge boom : 63.8 metres
Maximum High Cut height : 18 metres
Service Weight : 1450 Tonnes
ISN 104

105. 11,000 TPH SPREADER
Theoretical design capacity : 11,000 Tonnes/hr
Outreach from Receiving boom to Discharge boom : 135 metres
Working Gradient : 1 : 20
Service Weight ISN : 1450 Tonnes 105

106. BRIDGE TYPE 1400 LITRE BWE IN OPERATION
ISN 106

107. DUMPING OPERATION OF 20,000 TPH SPREADER
ISN 107

108. 700 LITRE BWE OPERATION IN LIGNITE BENCH
ISN 108

109. EXCAVATION WITH LOCAL DEPRESSURISATION
GROUND WATER PUMPING FROM MINES - 110 Mm3 / ANNUM
ISN 109
45 NUMBERS OF 1000 GPM PUMPS (20” DIA) ARE IN OPERATION

110. ISN 110

111. 5. Surface Miner Technology
ISN 111

112. 5. Surface Miner Technology
•Used for selective mining
•Larger strike length of about 600 m – 1000 m and
widths of around 300 m are ideally suited for surface
miner.
•Does not need drilling and blasting. The machine
cuts the coal & loads into trucks for onward
transportation to Surface
ISN 112

113. SURFACE MINER
Engine hp : 800
Annual production : 10 L. Cu.M
Gradient :1 in 10
Deployed for selective mining
ISN 113

114. SURFACE MINER SCHEMATIC DIAGRAM
ISN 114

115. Crushed Coal by Surface Miner
ISN 115

116. What is Surface Miner?
Surface Miner is :
- continuously operating mobile opencast machine
- it cuts consolidated soils and semi – solid rocks
without drilling and blasting
- the cut material is pre-crushed and suitable for belt
conveying, loading, transporting and transferred to
down stream means of transportation
ISN 116

117. Operation:
Surface Miner operates:
- according to the “Rock cutting technology”
- the cutting drum is provided with point attack picks
- which cut the mining face during the continuous
advance of the machine on crawler track assemblies.
ISN 117

118. ISN 118

119. ISN 119

120. A modern surface miner –
here's how it works
ISN 120

121. Technical highlight:
Clever design with central cutting drum
ISN 121

122. Working principle of Surface Miner:
the surface miner is crawler-mounted machine having a
cutting drum located b/w two sets of crawlers and positioned
at the center of the machine.
the drum is lowered and raised by hydraulic system with
powerful hydraulic motors therby varying the depth of cut.
the material cut is loaded onto the primary and secondary
discharge conveyors for loading the same onto the loading
/transporting equipment.
the rear crawler travel at lower level then the front crawlers to
adjust to the required depth.
ISN 122

123. REASONS FOR DEPLOYMENT OF
SURFACE MINER IN SCCL
Improvement of quality by selective mining of coal
Eco-Friendly mining of coal
Improved coal recovery especially in areas sensitive to
blasting
Less coal loss and dilution
Primary crushing and fragmentation of coal
Less stress and strain on trucks due to minimum impact of
the excavated material.
Since the cutting depth can be set with great accuracy, thin
seams can also be mined selectively with high purity.
Reduced capacity requirements for coal washing /
preparation plants. ISN 123

124. Specification of the Writgen
Surface Miner 2100SM
• Overall length - 15500 MM
• Overall width - 2500 MM
• Overall height - 4500 MM
• Milling/Cutting Width - 2100 MM
• Milling/Cutting depth - 0 – 250 MM
• Engine output - 448 KW/610 HP
• Maximum longitudinal tilting while milling - 1 in 4 (25%)
• No. of crawlers - 4
• Cutting drum drive - Mechanical
• Travel Drive System - Hydraulic/All crawler
• Production - 270 M3/Hr(Av.)
• Speed - 10 – 20M/Min.
• Fuel consumption (Full load) - 110 Ltr/Hr.
ISN 124

125. • Belt width (Primary conveyor) - 1000 MM
• Belt width (Secondary conveyor) - 1000 MM
• Theoretical discharge Performance - 550 M3/Hr
• Ground clearance - 350 MM
• Loading capacity - 550 M3/Hr.
• No. of picks/bucket - 76 Nos.
• Fuel tank - 1200 Ltrs.
• Hydraulic oil tank - 300 Ltrs.
• Water tank - 4180 Ltrs.
• Tare weight - 37000 Kgs.
• Operation weight (Fuel Tank) - 40500 Kgs.
• Cutting speed - 0.45 M/Sec.
ISN 125

126. ISN 126

127. ISN 127

128. Application & Advantages of
Surface Miner:
• Presently being used in KOCP-II for selective mining.
• Can work safely on a gradient of 1 in 10. However, presently
being worked in KOCP-II in gradient of 1 in 4.
• Annual productivity of the model 2000 SM is around 2.00 MT per
annum. However, high capacity of surface miner sare also
available.
• Larger strike length of about 600 m – 1000 m and widths of
around 300 m are ideally suited for surface miner.
• Does not need drilling and blasting.
• Can crush coal up to -100 mm.
• Cutting size can be varied by selection of equipment, speed etc.
• Two methods of coal removal are available – Wind rowing i.e.,
loading the crushed coal by front and loader on to trucks and
dispatch of the cut material by gathering arms on to a belt
conveyor and then to a waiting truck.
• At KOCP-II, Grade improvedISN from F to E by this technology. 128

129. MAJOR ADVANTAGES OF SURFACE
MINER TECHNOLOGY
Direct excavation of hard material without need
for drilling and blasting.
High productivity
Low cost for multi seam mining including hard
coal and overburden.
Possibility to link the machine directly to
continuous conveyor transport systems.
Higher recovery rate of coal
ISN 129

130. Precrushing of coal and elimination of primary
crushing plants high selective mining capabilities to
eliminate interbands to improve coal quality.
Surface Miner shall be very much needed for future
mining due to higher productivity, less hazard, eco-
friendliness, better quality of product, better
exploitation of mining property and also considering
the poor quality of coal from future coal seams to
have an economic solution for producing low ash coal
as per government regulations for power plants (less
than 34 % ash for transporting distance > 1000 km).
ISN 130

131. Constraints.
Steeper Gradient (more than 1 in 4)
Danger of Machine sliding along the High Wall.
Coal Seams Containing minute dirt bands (less than
5CM)
Dimensions of the coal bench.
ISN 131

132. Rock breaker
Rock breaker technology can be applied for breaking of rock/coal/ore
even about 500 kg/sq.cm.
It can be used wherever it is not possible to go for blasting – near
ISN 132
vicinity of structures and habitations.

133. Technical Parameters of Mega – Breaker
Make : INDECO
Model : 8500 UP
Weight : 4500 Kg
Dia of tool : 195 mm
HP : 120 HP
Striking rate : 350-450 Blows / Min
Pressure to
Breaker : 150-160 bar
Energy Class /
Blow : 10,000 joules
ISN 133

134. Working Parameters of Mega Breaker
Production / Hour : 190 – 200 tons
Production / Month : 55,000 tons
Diesel Consumption : 30 Lit./ Hr
Life of Moil point : 275-300 hours
Optimal Bench Ht. : 3 to 4 M
ISN 134

135. Advantages
Locked-up reserves can be mined easily
Reduction in Man power
Sump-deepening an easy affair
Digging of foundation pits adjoining the kiln /
valuable structures
More environmental friendly working &
maintaining better social relationship with
villagers
Effective working hours compared to
conventional working methods
ISN 135

136. Limitations
Floor-level will not be uniform as compared
to Surface Miner
Not suitable for mining huge reserves
Have to be dependent on a single machine
ISN 136

137. Cost Particulars
Total Capital Investment = 330 Lakhs
Cost of consumables = 1.2 Lakhs
Cost / ton of Limestone (Rs./MT) :
Owning Cost = 17.77
Operating Cost = 12.25
Total Cost = 30.02
Cost of Conventional Mining (Rs./MT) :
Total Cost = 24.80
ISN 137

138. ISN 138