Actom Air Pollution Control, a division of local electromechanical equipment and turnkey solutions provider Actom, is in the process of erecting the first of three baghouses in fulfilment of a contract awarded by global diversified miner Xstrata’s Lion ferrochrome complex, located near Steelpoort, in Mpumalanga.

This multimillion-rand contract, which was awarded at the end of 2011 for completion later this year, marks the largest contract to be awarded to the Johannesburg-based company in its 44-year history.

The contract entails controlling emissions from the complex’s new rotary dryer and two kilns that form part of Phase 2 of the smelter expansion project.

To accomplish this, Actom has been contracted to design, manufacture, supply, install and commission two suction reverse air bag filter baghouses for fume and dust extractions in the two rotary kilns, another for fume and dust extraction in the rotary dryer, seven pulse jet bag filters for de-dusting in the mill and pre-wetting opera- tions, ducting and materials handling equipment to service these installations and, lastly, fans and stacks.

“The total manufacturing package is 85% complete, with almost 50% of all equipment and other materials delivered to site,” says Actom Air Pollution Control marketing and sales manager Gerard Pretorius.

He adds that the main components of the rotary dryer baghouse have been erected, with the remainder due for installation at the end of the month.

The Lion ferrochrome Phase 2 expansion will increase the capacity of the smelter complex by 360 000 t/y, bringing its total yearly capacity to over 2.3-million tons.

Pretorius adds that the combined air-moving capacity of the two reverse air baghouses for the rotary kilns and the rotary dryer will be 1.4-million cubic metres an hour, with the total capacity of the seven pulse jet bag filters reaching 75 000 m3/h.

“All the bag filters are thermally insulated. Those in the rotary kiln baghouses will operate in temperatures of about 140 ºC, while the baghouse for the rotary dryer will operate in an average temperature of 180 ºC.

“Cleaning of the bags is done off line through automatic programmable logic controller-ope- rated dampers. The cleaning of each compart- ment is carried out while the rest of the compartments are in operation. Maintenance work is done on line by isolating each compartment concerned, which is achievable despite the high operating temperatures, as the compartments are independent modules,” he concludes.