JOHANNESBURG (miningweekly.com) – Repair work to the water leak detected in the high-pressure cooling section of the Anglo Converter Plant (ACP) Phase B unit of Anglo American Platinum (Amplats) is expected to be completed next week.

The Johannesburg-listed platinum group metals (PGMs) mining and marketing company said on Wednesday that once the repair work was completed, recommissioning of the Phase B unit would begin, provided a detailed risk-based assurance process had confirmed that it was safe to do so.

The ACP plant, at Waterval in Rustenburg, is a key part of Amplats’ PGMs production process of treating furnace matte from the company's smelters.

Amplats last week announced its decision to close the ACP Phase B unit temporarily to secure a safe operating environment, protect employees and protect the integrity of the plant.

Meanwhile, the detailed technical investigation into the cause of the water leak showed localised damage to a now-being-replaced single cooler tube, and confirmed that this leak was unconnected to the repair work recently completed on the ACP Phase B unit.

Whilst the ACP Phase B unit was off-line, other maintenance was being carried out and additional controls put in place to provide greater operational stability. 

Amplats said in its release to Mining Weekly that it would be adopting a prudent approach to safely ramping up the ACP Phase B unit, where increased monitoring would likely result in intermittent stoppages to inspect the plant, until the repairs to the ACP Phase A unit were completed. The ACP Phase A converter plant was damaged following an explosion within the converter on February 10.

As per normal business procedure, the ACP Phase B unit was commissioned to take over from the ACP Phase A plant when water was detected in the furnace as it was in the process of ramping up to steady state.

As a result of the temporary closure of the entire ACP plant, Amplats had to declare force majeure to customers, suppliers of third-party purchase of concentrate and suppliers of tolling material, which has since been lifted.

The repairs to the ACP Phase A unit were, Amplats said, progressing well, with completion now expected towards the end of this year owing to the successful accelerated procurement of key long-lead time items.

Concentrate from third parties, joint ventures and toll agreements would continue to be received and customers would continue to have metal delivered to them.

The stoppage of the ACP Phase B unit was, it added, not expected to have any impact on full-year refined production guidance, which remained at between 3.1-million PGM ounces and 3.6-million PGM ounces.

As Mining Weekly has reported, Amplats has had a shut-open-shut repair period at the ACP complex. On May 5 it announced that it had safely and successfully completed the repair of the ACP Phase B unit and that the ACP and full downstream processing operations were completing a safe ramp-up, with full operation from May 12.

But then on May 31 the company announced temporary ACP closure owing to the detection of the water leak in the high-pressure cooling system, which is now on its way back.