State-owned power utility Eskom on Friday reported that work was progressing well on preparing the first unit of the Medupi power station for synchronisation at the end of this year.

Eskom said good progress had already been made on the chemical cleaning of the Unit 6 boiler, with the chemical cleaning medium injection scheduled for August 15.

“Chemical cleaning is required to ensure that residual contamination and excess depositions, such as mill scale, welding slag and grease, do not contaminate product or cause severe damage to rotating machinery or valves,” the utility explained, adding that existing piping systems in service that were affected by contaminants, or organic and inorganic scales could, in time, reduce flow rates or affect heat transfer.

Chemical cleaning included various steps, including high-speed flushing to remove loose debris. The high-speed flush of the boiler had started on August 6.

Eskom also pointed out that, to enable the flush, all the boiler pumps that are used to fill the Unit 6 boiler had been successfully commissioned.