longwall mining
DESCRIPTION
This presentation givesa basic idea about Longwall mining in India.TRANSCRIPT
LONGWALL MINING
Status in India and its application for deep
seated deposits in international scenario
CONTENTS: Longwall : Introduction LW mining equipments LW mining : Importance Status in India Analysis of the problem Present and Future
INTRODUCTION This is a form of underground coal mining
where a long wall of coal is mined in a single slice (typically 0.6–1.0 m thick).
The Longwall panel (the block of coal that is being mined) is typically 3–4 km long and 250–400 m wide.
As a cut or slice is taken along the length of the wall, the supports are collapsed, advanced closer to the face, and re-engaged, allowing roof to cave behind.
EQUIPMENTS Powered Face Supports
Shearer
Armored Face Conveyor
FEW SCENES FROM A LONGWALL MINE
LW MINING: IMPORTANCE Present ratio of production:
UG : OC = 20 : 80 The reserves suitable for OC mining are
gradually depleting. To meet the future coal demand we
need bulk production underground technologies.
The present UG mines are operating at depths of 350m and the future extraction is from deeper horizons(300-600m).
LW Mining
Higher extraction
Increased safety
Suitable for thick seams
Better for deep seated mines
Higher Quality of coal
STATUS IN INDIA
First mechanized powered support Longwall caving face:• August 1978 at Moonidih, CIL.
First Longwall face • GDK 7 Incline in September 1983 in
SCCL
Indian coal industry’s experience with LW has been somewhat mixed .
Between 1978 and 1987, nine LW packages were deployed to extract some 5.4 million tons of coal in Jharia, Raniganj, Satpura and Godavari Valley coalfields.
The experience from the first generation Longwall faces was not encouraging. Average production at Moonidih was around 750
tpd while Dhemo Main and Pathakhera gave around 550 tpd
However, SCCL achieved around 1500 tpd . The production from about twelve operating
mechanised Longwall faces in India was just 1.15 million tons in 1993-1994
utilisation factor of man and machine was within just 26%-35%.
ANALYSIS OF THE
PROBLEM
Geo-mining Conditions
Faulty Planning
Improper Selection Management of Face
Longwall Support Selection Deficiencies
Large expansion in opencast
mining
Research needs
PRESENT ACTIONS
AND FUTURE NEEDS
Planning
Standardisation of Equipment
Spare Parts Management
Monitoring of Performance
Workshops and Overhauling Facilities
Indigenisation
Manpower Development
Thank You!