|Bulk Air Cooling System close to completion on Tanzanian mine|
BBE Projects is on track for the July 2010 commissioning of a new 7 MW bulk air cooler and two ammonia surface refrigeration machines, at African Barrick Gold’s Bulyanhulu Mine in north-west Tanzania, to counter the increased heat load arising from the mine’s expansion and deepening.
This turnkey project represents Phase 1 of a proposed 14 MW system and is believed to be the first bulk air cooling system to be installed on a Tanzanian mine. It is BBE’s third major cooling project in Africa (outside of South Africa), the first two being commissioned at AngloGold Ashanti’s Obusai Mine in Ghana in 2005 and 2007.
The project comprises a four-cell vertical forced-draught concrete bulk air cooling tower, two axial flow fans, a plant room housing two ammonia refrigeration machines with plate heat exchangers, a four-cell condenser cooling tower, and associated pumps, pipework, electrical, instrumentation and control system.
This US$13-million contract was awarded in 2009. Civil construction work is complete, mechanical installation work is well over halfway and the electrical contractor has established site. Equipment for this project was procured internationally and transported to the mine site by sea and road. Construction works have been awarded to local Tanzanian contractors.
Bulyanhulu is an underground trackless operation that uses long-hole and drift-and-fill as its principal stoping methods. Ore reserves are accessed via a surface shaft and an internal ramp system.
BBE’s mine refrigeration and cooling distribution team includes refrigeration and thermo-flow engineers specialising in design, installation and operation of all the elements of mine cooling systems. These include refrigeration machines, cooling towers, primary and secondary air coolers and in-stope chilled water systems. At concept level, BBE examines alternative refrigeration and cooling distribution systems and identifies optimum systems for specific circumstances. BBE has expertise in the detailed engineering design of mine refrigeration systems, the preparation of detailed engineering specifications, cost estimating and project execution and management for existing mines and new projects. BBE also has experience in the operational aspects of refrigeration systems and are often involved in assessment and modification work on existing refrigeration machinery.