Kirkalocka Process Plant Upgrade

Mintrex was engaged to design and document a new semi-autogenous grinding SAG mill and milling area for the Kirkalocka mine for full refurbishment after a decade of being on care and maintenance.

The mine’s ownership changed hands several times before Adaman Resources acquired Kirkalocka in 2018 and re-started production in the December 2019 quarter.

Mintrex was initially engaged in October 2018 by Adaman to complete early design work, reviewing the layout and key design documents.  Two months later, when MACA Interquip was appointed EPC contractor for the project, they engaged Mintrex for detailed engineering design.

The brownfield project near Mount Magnet required the new mill to be built alongside existing infrastructure, enabling Adaman to expand the total throughput capacity to 2.1 million tonnes per annum.

Mintrex provided drawings and specifications for the concrete, structural steel, and mechanical installation required to incorporate the mill into the circuit.

“We had to interface with the existing structure and equipment,” project manager Huy Nguyen said of the challenge.

“On top of that, we aimed to minimise the change.” Costs were reduced by keeping the new SAG mill separate from the existing structure to simplify design and construction.

In three years, when the mine is expected to process harder ore, the existing ball mill will come into operation. “So, our design allowed an option to enable that change in the future,” Mr Nguyen said.

The scope of work included concrete foundation design and concrete reinforcement specification for the new SAG mill.  Being the first time this vendor had supplied into Australia, Mintrex facilitated design communication and deliverable to minimise concrete quantities.

Other work included structural steel design and detailed shop drawings for the SAG mill feed platform and steel platework drawings associated with the mill boil box, feed chute, and discharge hopper.

The design team had a tight timeframe of 24 to 26 weeks to complete their work before construction began in February 2019 with completion expected in September 2019 ahead of the plant’s planned commissioning in the December quarter.

Understanding the commercial benefits of delivering an operating plant on time, the Mintrex design team delivered procurement documents for mechanical equipment and structures despite a very compressed schedule.  Early selection of equipment and relentlessly disciplined management of change supported this achievement.