||Technology in Australia 1788-1988
Table of Contents
I The Present Energy Economy
II Australian Energy Consumption
III Research And Development
i Transition at the coal face
ii Further development of face mechanisation
iii Mechanisation outside the face area
iv Open-cut mining in NSW
v Open-cut mining in Queensland
vi Underground mining in Queensland
vii The state of the art
V Oil And Natural Gas
VI Solar Energy
VII Nuclear Energy
VIII Bagasse Firewood And Other Biomass
IX Electric Power Generation And Distribution electric Power Generation And Distribution
X Manufactured Gas
XI Industrial Process Heat
The state of the artUnderground
The advent in the early 1950s of the continuous miner underground immediately posed the question of its integration with a continuous conveying system which would eliminate the intermittent down time due to shuttle car rotation behind the miner, and automatically lead to increased productivity.
Nevertheless, by 1959 it was concluded by the Bituminous Coal Association in America that some of the technical problems inherent in this conception were a long way from solution and a monitoring committee was established to observe and, if possible, assist in developments. It may be some indication of the slow rate of technological development, that despite the urgency of this project and the great financial returns that could accrue, it is only now (1987) that two units have been manufactured and are being tested underground in Australia. These units made by the Joy Manufacturing Company and Klockner-Becorit have every indication of being successful and if so will mark another major technological advance for the coal industry.
This will leave only one outstanding challenge to be overcome in the use of continuous miners; the cyclic securing of the roof as the machine progresses, which again introduces a down-time factor to its cutting operations. Although speeding up the bolting cycle has considerably reduced the delay caused by this operation, the complete cycle mining, conveying and roof support, has not yet been reduced to a non-stop operation.
When the electrical equipment in use for modern surveying is acceptable to underground mining the concept of total stations will be permissible, thus eliminating the standard practices of many years and rendering faster and more accurate results.
Open-cut and open-pit mining
This method certainly achieves the maximum in flexibility but at a high cost, so that in-pit conveying is becoming more popular allied with in-pit crushing. However, these units have so far been restricted to normal conveying grades, say 18 degrees maximum.
Overall technological application in coal mines
Basic aims of mine planning
According to Jeffrey 'The basic aim of mine planning is to design mine layout and schedules that allow operations to be optimised, costs minimised and so the recovery of the resource maximised'. The mine planner of today, thanks to improvements in exploration techniques, has a substantial input technique included in his initial plan. Seismic surveys over the proposed development area will show the position of major faulting and intrusions and other geologically disturbed areas can be indicated that may call for further drilling.
The geotechnical testing of bore cores can reveal important information on rock types from the surface to the seam which indicate what strata are competent and to what extent; where fracturing exists; what rocks are susceptible to rapid breakdown on exposure and, among other things the most important of all, the likely behaviour of the mine roof under working conditions. Within the seam, in-seam seismic is in process of development to the stage where minor dislocations of the seam can be detected in front of the advancing face -a major consideration in longwall operations.
Organisations in Australian Science at Work - Joy Manufacturing Company Pty Ltd; Klockner-Becorit Australia Pty Ltd
© 1988 Print Edition pages 795 - 797, Online Edition 2000
Published by Australian Science and Technology Heritage Centre, using the Web Academic Resource Publisher