Published in the March 2014 International Coal News Magazine

The company is using new longwall technology to help it achieve better productivity at the mine as it seeks to lower operating costs across the group.

Springvale colliery has been drawing some of the limelight from its sister operation at nearby Angus Place since the Joy longwall was installed late last year.

The mine is hitting its straps and emerging as a major contributor to productivity in Centennial’s New South Wales stable of coal mines.

Thai energy group Banpu wholly acquired Centennial Coal in 2010, which mines and supplies thermal coal and coking coal to the domestic and export markets.

It operates seven coal mines, both underground and open pit, in the north and west of NSW, with a total annual production capacity of about 18 million tonnes.

Springvale, along with Centennial Coal’s Angus Place and Clarence, lie in the NSW western district near Lithgow.

Short-term issues at Springvale and Centennial’s Mandalong mine in the northern district during the 2013 third quarter reduced production and accordingly increased unit costs.

Centennial Coal’s Q3 sales volumes dropped 15% quarter on quarter to 3.22Mt. Its average selling price was sustained at $A70.90 per tonne, which was 5% higher year on year with gross profit margin at 29%, compared with 32% in the corresponding 2012 quarter.

Sales revenue for Q3 was $US214.37 million compared to $298.08 million for the previous corresponding period. Gross profit for Centennial in Q3 was $61.25 million compared to $96.19 million in the previous corresponding quarter.

Following the closure of the Airly and Mannering mines and other cost cutting measures, the company has removed $A100 million from the 2013 cost base when compared with 2012.

Despite these measures, the combination of a high Australia-US dollar exchange rate and soft export prices together with short-term issues at Springvale and Mandalong means Centennial is expected to report a loss for 2013.

Springvale continued to experience challenging mining conditions during the Q3 2013, resulting in decision to move to the new longwall sooner than anticipated. Difficult mining conditions also impacted the previous longwall at Springvale.

Another hiccup came from the bushfires that raged through NSW during the early part of the fourth quarter, resulting in five days lost output at Clarence and Springvale, with the rail network affected for two weeks.

SPRINGVALE LONGWALL

The commissioning of the next generation longwall at Springvale has been completed with production ramping up.

The next generation high-productivity longwall is comparable to that installed at Angus Place, with the company expecting similar improvements.

The longwall is designed for Springvale conditions and the mine design and layout re-engineered to address poor roof areas.

The longwall face width has also been reduced for improved face control.

As a result of recent poor geological conditions and consequently low productivity rates from the 20-year-old longwall equipment, a decision was made to cease production in longwall block LW415, approximately 200m early.

Production commenced in the adjacent block (LW416), where the equipment had been pre-installed and commissioned, with the longwall already demonstrating its productive capability.

Following installation of the latest generation longwall, Springvale’s productive capacity matches that of the neighbouring Angus Place mine.

Over the past two years Centennial Coal’s Springvale mine has been in the process of purchasing a complete Joy Global manufactured longwall mining system.

The system is a “life of mine” investment for Springvale and will be used for the next 20 years.

A total of 727,000t of steel was used in the manufacturing process, which was completed in Australia, Europe, Asia and the US. The longwall face is 251m long, powered by a 4.5 megavolt ampere substation and three 309 litre per minute high pressure hydraulic pumps.

Services to the longwall face are handled by a 547m long monorail system.

The system can potentially fully automate the cutting cycle and includes the Longwall Automation Steering Committee inertial navigation system onboard the shearer to assist in face control.

“Together, the monorail system and new longwall provides Springvale with a modern, more effective and efficient longwall operation,” Banpu said.

The supports handle the geological conditions well with better tip to face and increased support integrity compared to the previous equipment. The longwall has progressed through the lithology change without problems and the supports are dealing well with poor tailgate conditions.

No cavities have been experienced since introduction of those supports.

Cutting rates have improved to more than 1000 tonnes per hour due to the introduction of the equipment, compared with the previous longwall, which was operating at approximately 700-800tph.

The rates will improve further with a belt upgrade (speed up).

FUTURE

Springvale proposes to extend its underground mining operations within its approved mining lease and exploration licence areas to the east and the southwest of its existing operations.

Springvale’s development consent will expire in 2014.

Accordingly, Centennial is seeking a renewal in order to continue mining.

Under the consent renewal, Springvale is proposing to upgrade existing site infrastructure, continue underground mining operations with an increase in the mine’s coal extraction capacity from 3.5 million tonnes per annum to 4.5Mtpa and to amalgamate the mine’s coal processing and distribution network into Centennial’s Western Coal Services operations.

The project will allow the mine to continue operating and secure local jobs, while the local and regional community will also continue to benefit from the mine’s positive economic contribution. Centennial is proposing to upgrade the existing infrastructure within the Western Coal Services site.

Located north of Lithgow near Blackmans Flat, the project is being developed to provide an upgraded, integrated approach to coal handling and distribution between Centennial’s western operations.

The facility receives coal by overland conveyor from Springvale and provides coal storage, handling and processing functions.

Coal can be transported by overland conveyor to either Mt Piper Power Station to the north or Lidsdale rail siding to the south.

Key stats/details

• Face Width, metres (m) 251.3

• Face Length, metres (m) 2540

• Roof Support Ratings in tonnes Gate ends 8 off 1200t, run of face 137 off 1156t

• Roof Support Width 1.75m; Height range 1.8-3.6m

• AFC linepans 900mm Raceway x 304mm high x 1756 long x 139 linepans

• AFC transmissions L1000EP & L1000BP with 855 kilowatt motors

• AFC couplings Voith TTT 562

• BroadBand Long Life Chain 42mm twin centre strand broadband

• Turbo transmission technology Voith TTT 562

• Outbye equipment: Stageloaders 1000mm Raceway 38mm mid-board strand broadband chain/s300E gearbox/Voith 562 TUVF coupling/250kW motor

• Crushers S503HD gearbox/Voith 562 TUVF coupling/250kW motor

• Mobile belt tail pieces 1200mm fixed drum Matildas with 1100mm overlap

• Shearer specs: Model no 7LS2A/3A

• Cutting height 3.2m, Machine height 1.333m; weight 50t

• Frame thickness 588mm; Haulage pull 160kW; Max haulage speed 30 m/min

• Pump motor 11kW; Haulage motor 80kW; Lumpbreaker motor N/A

• Ranging arm model no J525F;Length of ranging arm 3m

• Cutting motor 60 hertz (max) 50Hz 480kW

• Min drum diameter 2.050m;Min drum width 1.064m

• Drum speed (60Hz) 41rpm/50Hz

Following installation of the latest generation longwall, Springvale’s productive capacity matches that of the neighbouring Angus Place mine.