Matla production manager Chris Silver and mine manager Heine Booysen presented at the Longwall 2004 conference in the Hunter Valley last week. Whilst in Australia the duo are also working in visits to German Creek Central, Beltana, United, Moranbah North, West Cliff and North Goonyella to assess technology and practices that could be applied to Matla.
The Matla complex, located 150km east of Johannesburg in Mphumalanga, is owned by Eyesizwe Mining and consists of two shortwalls, three development and four bord and pillar sections, to produce some 15 million tonnes per annum.
In March the mine produced an amazing 722,586 tonnes from a 130m wide face, a world record for a shortwall. Total mine output for the month was 896,458t, including development tonnage, equating to 2,409 tonne per man per month. Shortwall productivity measured 9,032t/man/month during March.
The record was achieved during the mining of the 3km long panel 13, which took a total of four months and two days to complete.
Several factors contributed to the record; excellent ground conditions contributing to the high rate of retreat, the pantechnicon's ability to handle the high rate of linear retreat, an effective underground transport system which includes road building and non-flameproof vehicles, the older, more experienced workforce (average age 44) and excellent labour relations between management and unions, and the experienced and highly dedicated management team.
On the equipment front, Matla No 3 mine has a Joy 6LS05 shearer, with installed power of 1500kW and a drum diameter of 2.29m. The shearer operates at an average cutting height of 3.82m and uses a web cutting cycle known as the Opti-cycle which has been shown to be 15% more productive than bi-directional cutting.
While all is running well at Matla, Silver and Booysen have their eyes firmly set on the long term future of the mine. Infrastructure will need to be dramatically increased to meet the future demands.
Conveyor belt lengths will be one of the challenges, an area Silver and Booysen planned to assess whilst in Australia.
They said 5.5km of conveyor would be needed with a single drive able to handle 3500t/hr with a headgate drive and two booster drives. Whilst in Australia they hoped to discover some of the hassles associated with a conveyor of this length and ways to overcome the challenges.
Automation was another area the two planned to observe. “South Africa’s labour cost is low, so at this point we don’t have much on an issue with automation, but we perceive it to be an opportunity further down the line,” Silver said.
“Our reasons for automation would be for productivity and to counter the situation of losing a skilled workforce to age. Mining is not that popular now days and as people leave through age we will not be able to recruit the skills we require.”
Dust reduction is another subject of concern for the mine. The operation averages five to seven mg per cubic metre, well above its American counterparts who by legislation are required not to exceed a permissible exposure limit of 2mg/m3.
The mine is currently conducting a research project with South African government researcher CSIR looking at pick configuration and directional sprays to reduce respirable coal mine dust.
