:: Aker Kvaerner to Provide Engineering Services for the Lisheen Paste Backfill Plant in Ireland

Lisheen Mine has awarded AK Engineering Services, part of the Aker Kvaerner Group, a contract to provide Engineering, Procurement and Construction Management services for a Paste Backfill plant at the mine in County Tipperary, Ireland. The Lead / Zinc underground mine is owned by Anglo American Plc, and has been operating since 1999. 20 Nov 03

The backfill plant will be able to treat 100% of the existing lead / zinc concentrator tailings and will produce a consistent cemented paste at around 76% solids that can be pumped underground. Placement of the paste in existing stopes will allow additional ore to be mined, improving the overall recovery from the mine and reducing the requirement for surface impoundment of tailings.

The project, with a contract value of GBP1 million to AK Engineering Services, comprises of a surface plant incorporating an 18-metre diameter Deep Cone Thickener and underflow pumping system, 400 tonne cement silos and colloidal mixing equipment, and a continuous spiral mixer. It also includes two hydraulically-driven, positive displacement piston pumps (each rated for 131 m3/hour and 80 bar continuous operation) and an underground distribution system to enable the cemented paste backfill to be pumped up to 3.5 km via a 200 mm pipeline to the underground stopes.

"This environmentally-friendly project continues the excellent working relationship between the Lisheen Mine and AK Engineering Services, which has been built up over a number of years," said Malcolm Oliver, President of AK Engineering Services.

Don Cunningham, General Manager, Lisheen said, "We are looking forward to working with AK Engineering Services and to contributing to and commissioning a fully operational plant safely and ahead of schedule."

The project starts immediately and is scheduled for completion in September 2004.

AK Engineering Services was responsible for the project management, basic and detailed design, procurement, construction, and commissioning of the 1,500,000 tonne per year lead/zinc processing facility and associated infrastructure. The USD 52 million lump-sum, turnkey project was completed in September 1999, after just 87.5 weeks.