Image: Curragh: One of the largest coal reserves in the world

Minerals & Metals2 min read

Curragh: One of the largest coal reserves in the world

Central Queensland, Australia
2009 - 2012

Curragh is an open-cut coal mine and one of the world’s largest coal reserves.

In 2009, Wesfarmers engaged Ausenco QCC to deliver a Feasibility Study followed by an EPC contract for the Curragh Coal Handling and Preparation Plant Upgrade.

The Challenge

Curragh’s coal reserves consist of thermal coal and a large amount of high quality, low-ash metallurgical coal including hard coking coal, super clean coal and pulverized coal for injection. The variety of coal types led to a complex design flowsheet to maximise the coking coal production.

We were challenged to draw on our extensive experience in brownfield upgrades to deliver the project efficiently, cost-effectively and with minimal disruption to the existing operation.

During construction - in late 2011 and early 2012 - a significant rain event across Queensland isolated the site and damaged major roads throughout the region, significantly delaying deliveries to site. When the engineering office was flooded, we established a temporary office to continue to support the project.

The Better Way

Despite the complicated flowsheet, our team of highly experienced coal experts delivered the new plant, including raw coal screening, two stages of dense medium cyclone, spirals and froth flotation. The new design can process coal in various sizes and envelope density to produce different types of products. The new washery maximised the recovery of high value, hard coking coal within tight product specifications, while operating with high proportion of near-density raw coal.

The new design maximised product recovery from the tailings stream, which significantly helped reduce the amount of residue and impact on the environment.

For the plant to operate efficiently, the coal handling process needed to provide raw coal delivery and the stockpiling of product coal to two preparation plants, using a system originally intended for a single plant. The raw coal delivery system required an innovative approach to convert the existing raw coal bins to a dual feeder arrangement, within the layout constraints posed by the existing facilities. The upgraded facility was able to maintain stable and unbiased feed to the new and existing plants.

The Outcome

By using the best project management systems, strategies and processes, we executed the EPC delivery while minimising the impact to the existing operation.

The new plant achieves a maximum capacity of 1,750 t/h and exceeded Wesfarmers’ requirements for efficiency and throughput. One of those requirements included processing two million tonnes of coal during the commissioning phase. With a team of committed commissioning experts, Ausenco QCC successfully met the requirement and delivered the project for Wesfarmers.

Completed in 2012, with design starting in December 2009, the plant is still in operation and meeting production targets ten years later.