Materials handling company Clyde Bergemann Africa (CBZ) is currently supplying a fly ash handling system to platinum producer Impala Platinum (Implats) to improve the operation of its boiler system.

CBZ is part of Clyde Berge- mann Power Group, a global group of companies supplying systems and solutions for the energy services market.

Implats’ boiler system supplies the process steam for the Bushveld Complex operation, in Springs. The fly ash handling system will ensure the efficient transport of ash from the operation’s small multiple boilers to a storage silo, reducing downtime and maintenance costs of the boiler system, owing to ash build-up.

“CBZ supplies solutions that improve the operation of furnaces and kilns by controlling everything that is supplied into and cleared from firing systems. If ash and other residue are not cleared from within firing technology, the build-up reduces efficiency,” says CBZ executive director Jeremy Kirsch.

The company also supplies a furnace analysis, control and operating system (Facos).

This system ensures the efficient operation of boilers, as it improves the heat transfer from burning fuel to water to produce the super-heated steam required for various processes.

Kirsch explains that a dirty heat transfer system creates more resistance in the heat transfer process, resulting in the heat escaping along with the flue gas.

The system analyses information provided by boiler monitoring systems to identify when boilers need to be cleaned. Facos also enables users to specifically determine where ash build-up is taking place in the boiler system.

“Previously, sequential cleaning was done on boiler systems as one was not able to detect where the build-up that affected the heat exchange was taking place. Facos enables condition-based monitoring and cleaning, which help one to develop an understanding of where build-ups take place through the identification of various patterns,” states Kirsch.

CBZ is currently in talks with power equipment vendor Hitachi Power Africa to supply Facos to State-owned power utility Eskom’s Medupi and Kusile coal-fired power stations, which are cur- rently under construction.

Boiler-cleaning technology is also used to prevent serious accidents.

Many solid particles get carried over with the gas through the large- diameter ducts that project out of the kilns, furnaces or dryers. Over time, these solid particles build up and start reducing the diameter of the duct, which increases the resistance to gas flow.

These ducts operate at signifi- cantly high temperatures and, before cleaning can take place, the system has to cool down. If cleaning has not been performed, the task becomes significantly difficult and time consuming, Kirsch explains. “The residue build-up hardens to such an extent that jackhammers and shotguns have been used to remove it.

“The build-up of residue is a serious problem and, without the use of online boiler-cleaning technology, serious accidents can take place,” he notes.

Further, once the resistance in a duct, caused by the build-up of residue, becomes too large, the fans will fail to extract the flue gas, resulting in system failure and downtime.

“The use of CBZ’s online boiler- cleaning technology enables cleaning to take place during the operation of the process. This ensures that downtime is reduced and operations do not have to stop for the system to be cleaned. This continuous cleaning of the system also ensures that, when downtime is undertaken, there is minimal residue, which is easily cleaned,” says Kirsch.

CBZ’s clients include soda ash and chemical-grade salt supplier Botswana Ash, to which it supplied a solution for two fluidised bed boilers, copper-nickel ore miner Bamangwato Concessions Limited, in Botswana, Chingola-based company Konkola Copper Mines, in Zambia, miner Anglo Platinum and other platinum miners in South Africa.

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