March 18, 2024 State of the Art Electrical Upgrades Boost Mine Uptime

Sustainability, employee protection & operational insights of an electrification upgrade at BHP BMA’s Goonyella Riverside Mine in Queensland.

At the BHP-Mitsubishi Alliance (BMA) conjoined metallurgical coal mines Goonyella and Riverside in Queensland’s Bowen Basin, Subra Nedunuri is responsible for delivering capital electrical projects without compromising environment, safety, quality, or mining schedules.

When a 43-year-old section of Goonyella Riverside’s power infrastructure became unreliable, Nedunuri began designing an upgrade with ABB state-of-the-art capabilities which protect employees, equipment and the environment, and enables predictive maintenance of 16 pumps critical to the mine’s operation.

Subra brings a wealth of business and engineering qualifications to the role of Senior Project Manager at Goonyella Riverside Mines (GRM). He says these are complex projects as their complexity and value to the mines are disproportionate to their cost of implementation compared to other projects.

“A rehabilitation project to move earth from one side of the mine to the other may cost $20 million, but in contrast this $3 million electrical upgrade can save lives and hundreds of millions of dollars in downtime.”

To power the coal wash treatment plant, pumps are used to direct water for reuse or into tailing dams, without them the plant can’t operate. In the past, the now obsolete electrical system communicated only three states of condition for the pumps operation – “On”, “Off” or “Fault”. The system had no protection against arc flash incidents (explosive releases of energy when an electrical arc travels through ionized air to ground or another part of the electrical system), which endanger the lives of service technicians and nearby workers.

For the upgrade, BMA had a wishlist of not only the safest switchgear to protect its employees, but a human-machine interface (HMI) that would enable remote and onsite monitoring and control of the electrical system and pumps around the clock.

Digitalization future proofs production

Henry Lin, Project Manager for Electrification Service at ABB in Brisbane, notes that the division is known for working closely with customers to modernize their electrical infrastructure, by upgrading obsolete analogue products to next-gen digital solutions so the site can then take advantage of interconnectivity and smart automation.

ABB’s system-integrated Ultra-Fast Earthing Switches (UFES) formed the basis of GRM’s upgrade with safety, and protection of the people within the vicinity of the equipment in mind.

“The switch is installed into the panel to prevent an arc flash, if it occurs it will be detected and switch off the power in less than four milliseconds,” Nedunuri said.

“In addition to UFES-enabled switchboards, the mine wanted to take advantage of new and trending technology in the form of digital communications between the switchboard and the plant.”

ABB Ability™ Electrical Monitoring and Control for Distribution Networks, known as ZEE600, integrates diverse devices from a variety of suppliers, under the IEC 61850 standard of communication preferred by BMA. At GRM, this Condition Monitoring solution harnesses the real-time diagnostic data of substation equipment and electrical assets – primarily the pumps – to alert onsite teams to respond with preventive maintenance.

Nedunuri said it’s all connected back to plant supervisory control and data acquisition (SCADA).

“Via the HMI, you can actually see the health of the pumps, motors and starters – everything. Our analysis and improvement team also continuously collect the data and analyse it for troubleshooting and future enhancements,” he said.

Functional pre-test ensures seamless commissioning

Installation and commissioning of the upgraded system took place during the mine’s biannual three-week-long scheduled maintenance shutdown in August/September 2022.

The shutdown schedule must be followed to the letter, and every new piece of equipment has to come back online as planned, or production suffers.

Nedunuri said during the shutdown we do not have time to fix faults.

“I’ve learned to leave nothing to chance when it comes to a delivered system matching ‘what’s on the ground’ in mine switch rooms,” he said.

Prior to the shutdown period, Nedunuri painstakingly constructed the system at ABB premises in Brisbane. Together with the ABB technicians they matched cabling inlets and outlets with a template of the GRM system.

Nedunuri said when you have a switchboard and cable coming in and out from beneath it, that’s called a gland plate and we make a cut-out in the floor that aligns with the plate.

“If those dimensions in the new system are wrong, the switchboard will sit on the slab and you can’t penetrate a cable there,” he said.

Modifications are always required to match the existing substation setup, and it’s better to do that and test the modified system before the scheduled installation, to ensure it will run as planned in situ.

He states it is better to spend $100,000 upfront instead of losing $100 million in downtime!

Nedunuri appreciated working with the ABB Brisbane team because, he says they always preferred to do the job correctly the first time, without compromising in any way.

Pursuing reliable availability of assets

Lin says their customers need to reduce the risk of costly downtime.

“Our main objective in these projects is to ensure that our customer’s assets operate at peak performance levels and are available as required,” he said.

BMA has performed much research on the digitalisation of its mines and the ongoing upgrade of infrastructure involves a constant rollout of individual projects.

When it comes to the safety and reliability of electrical infrastructure, Nedunuri said the company doesn’t compromise, regardless of the cost.

“All upgrades must not only comply with Australian Standards, but also require ongoing modifications to meet the higher bar set by BHP BMA to make sure it runs efficiently and effectively into the future,” he said.

“I feel proud that I eliminated a huge risk to the business through the pump electrification project. We are protecting people using the new system with arc flash mitigation and at the same time, the monitoring and control enabled by ABB ZEE600, not only improves pump efficiency, but also adds a lot of functionality – it’s easy to operate and easy to maintain.”

BMA and ABB are collaborating on a pipeline of further potential upgrades to existing on-site installations, with each project planned to deliver greater safety, reliability, and sustainable growth.

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