surface miner
TRANSCRIPT
Krishna Kant
Indian Institute of Management Calcutta
TECHNO-ECONOMIC FEASIBILITY ANALYSIS OF
SURFACE MINER Vs SHOVEL IN COAL MINING
1
Mining with shovel-dumper combination
Why surface miner ?
Working principle and various mining methods using surface miner
Applicability and Favoring Issues
Advantage with Windrow method
Surface Miners in use
Sustainability with Surface Miner
Cost benefit analysis- a case study
Conclusion
Agenda
2
Mining with Shovel –Dumper combination
DRILLING BLASTING
EXCAVATION
UNLOADING AT CRUSHING PLANT HAULAGE 3
Shovel
Drilling Blasting Loading Crushing
Continuous Surface Miner
+ + +
The conventional method of mining includes –
Drilling, Blasting and Face loading. These Mining operations frequently involve a high degree
of environmental disturbance in terms of fly rock, ground & air vibration, dust and noise.
Cost of mining and quality control are the main issues .
To overcome the above problems and to minimize the adverse impacts of mining it is
desirable to adopt an eco-friendly mining technology.
Direct
loading
Crushed
aggregate
Continuous
cutting
Clean, level &
stable surface
Precise
cutting depth
Why Surface Miner?
4
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
thereby varying the depth of cut
The material cut is loaded onto the primary and secondary discharge conveyors for
loading the same on to the loading / transporting equipment.
The rear crawler travel at lower level then the front crawlers to adjust to the required depth
Turn Back Method
Working Principle of Surface Miner
5
SIDE CASTING
INDIRECT LOADING (WINDROW)
DIRECT TRUCK LOADING
Various mining methods using Surface Miner
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Flat or gently inclined deposit.
Best suited for rock compressive strength up to 60 MPa.
Less abrasive rock.
Non sticky material
Thin seams or thin dirt bands
Sized material production
Environmentally sensitive areas where blasting is prohibited or restricted.
In general surface miners are capable of cutting rocks of hardness b/w 10-80 MPa. Under certain
circumstances (E.g. Highly fractured material) even harder material can be cut economically.
Applicability
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Mining coal with a high production and performance rate without using blasting
Environment: Without abnormal sound, ground vibration and dust
Selective mining: Improving coal quality, capable of thin seam extraction
Sized product: Eliminates primary crushing of mineral completely Reduces the
time, effective carrying capacity of haulage equipment fetching more money and
minimizes damage to trucks deployed for loading
Manpower: Needs less workforce as compared to traditional mining with shovel as
excavator
Safety: Safe in Naxalite effective areas as no explosive is required. Also, Hard
surface less chances of fire and slope instability
High available time utilization: No drilling and blasting related wastage of
time.(from approx. 5,000 to 6,000 operating hours per year)
Overall mining cost :Reduces due to no drilling, blasting and primary crushing.
Favoring Issues
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Even and solid surface which was initially produced by the Surface Miners allows
effective loading operations for the front-end loaders and the fast and safe operation of
the additional trucks.
It guarantees a higher productivity rate for the Surface Miners since there are no waiting
times for the trucks involved.
The cut material which has been laid down in advance can be used as a mine stockpile
(emergency buffer).
Loading can be done on demand.
L&T: KSM223, KSM 303,KSM304
Wirtgen: 2200 SM, 2500 SM, 4200 SM
Today, more than 120 Surface Miners are used for coal and limestone mining in India
Used in Singereni Collieries Company Limited,Mahanadi Coal Fields ,South-Eastern
Coal Fields and Central Coal Fields of Coal India Ltd.
Advantage with Windrow method
Surface Miners in use
9
We are competing for finite resources in a world that is increasingly focused
on sustainability, so we have to invest in a manner that not only strengthens our
competitiveness but also produces maximum benefit for local communities.
Ingredients of sustainability with Surface Miner :
Environment friendly- better Air quality ,less Noise and vibration
Optimum use of resources in a scientific /systematic manner to extract maximum
resources in the most economical scale
Safety -A safe working environment where the employees can meet production
objectives without risk of injury
Sustainability with Surface Miner
10
05
10152025303540
Shovel SM(Windrow) SM(Direct)
Loader Cost
Crushing Cost
Blasting Cost
Drilling Cost
Shovel/SM Cost
Assumptions/data taken:
7.5 Million per annum coal excavation
Various figures taken are from practical experience/equipment manufacturers
Coal is moderately hard( Compressive strength~14MPa.)
Figures may vary for different mining conditions and output required
Remark: Cost incurred due to dilution of coal with waste has not been included
Rs p
er
MT
Calculations
Cost benefit analysis-Mandakini Coal Mine
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Electric Powered machines are more cost effective but flexibility is lost.
ROM coal with high quality will be produced due to less dilution from waste by
application of Surface Miner.
Surface Miner with Direct Loading gives maximum cost benefits but it requires
high level of supervision and control.
The Surface Miner with Loader combination gives the highest selectivity and
flexibility in operation involving changing mining conditions .
Combination of Direct Loading by Surface Miner and Surface Miner-Loader
combination methods gives best results.
Use of Surface Miner gives other benefits over Shovel like mineral
conservation, it is more environment friendly and safe.
It is recommended method in blasting restricted and Naxalite affected areas
Suitable machines/equipment have to be selected by studying parameters
such as ease of rock excavation, ability of high selective excavation, rate of
production and productivity demands, capital and operational cost and mine
features
Conclusion
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http://www.wirtgenindia.com/
http://www.larsentoubro.com/
http://www.google.com
Dey, K (1999), Performance Analysis of Continuous Surface Miner in Indian
surface Coal Mines-a case study, M-Tech Thesis, Department of Mining Engg.
Indian School of Mines University, Dhanbad.
Sen, P. and Dey, K.(2000), Continuous surface Miner in Indian Surface Coal
Mining, A case study, surface Mining (BrounKohle & others),52(2000),No.4
July-August,pp371-376
References
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S.No. Cost in Rupees/MT SHOVEL SURFACE MINER
(WINDROW)
SURFACE MINER
(DIRECT LOADING)
1 Total Owning & Operating Cost per MT 12.42 14.30 24.33
2 Drilling -Total Owning & Operating Cost
per MT
2.57 - -
3 Blasting Cost per MT 18.13 - -
4 Primary Crushing-Total Owning &
Operating Cost per MT
4.56 - -
6 Loader for loading in dumper -Total
Owning & Operating Cost per MT
- 14.92 -
7 OVERALL COST PER MT WITH LOADER 37.69 29.22 24.33
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