Yallourn upgrade

Rebuilt: Yallourn power station received a new pulverised fuel mill. File photograph

ZAIDA GLIBANOVIC

By ZAIDA GLIBANOVIC

YALLOURN power station Unit 1 has received a new pulverised fuel mill after two years of assessment and engineering work following the failure of the mill on March 20, 2021.

EnergyAustralia recently announced a $400 million investment over two years at Yallourn power station, with aims to improve asset reliability, safety and performance ahead of the station’s proposed closure in mid-2028. The total rebuild of Yallourn’s Unit 1 pulverising mill cost several million dollars.

EnergyAustralia Head of Yallourn Greg McIntyre said, “we are incredibly proud of the hard work of many people at Yallourn to have this mill safely back in service. This project represents two years of diligent work by the team, to ensure we have a much safer and reliable plant.”

The incident in March 2021 was a result of a failed fuel mill that lead to a fire on-site that was quickly brought under control with no injuries and investigations were completed without interruption to the electricity supply from Yallourn.

Reports of the incident stated a catastrophic explosion in one of Yallourn’s pulverised fuel mills on March 20, 2021, with photographs showing the casing around the pulverising mill’s shaft completely blown apart sparking a fire with debris flying 20 metres away.

Since then, EnergyAustralia has conducted investigations to determine the cause of the 2021 failure and how to improve the safety and reliability of its processes at the Yallourn power station. The report’s findings have resulted in a mill rectification program. In this program, EnergyAustralia completely rebuilt a new mill and rectified the failure mode and replaced bolts on their other 31 mills.

“There has been a great commissioning effort to ensure the new mill, was brought back into service in a safe and reliable manner,” Mr McIntyre said.

“This is a very proud moment and is a great example of what we can achieve when we come together, in the face of a massive challenge.”

Yallourn has 32 pulverising fuel mills with eight mills per unit, the function of these mills is to process around 25000 tonnes of coal per day each to ensure efficient combustion in the power stations boilers. For large coal-fired power plants, pulverised-fuel technology is widely used. Using such technology, the fuel particles are moved by air pressure at a high velocity through a burner nozzle into the furnace.

Mr McIntyre said the accelerated $400 million investment will support improvements in the reliability of electricity supply from Yallourn until its planned closure in mid-2028.

Among the accelerated program of investment into Yallourn to cover scheduled major outages for each of Yallourn’s four generation units over 2023 and 2024 includes works to support plant integrity, including pressure parts, turbine-generators including the replacement of a primary economiser, turbine repair works, rotary air heater pack replacements, water wall tubes and superheater bifurcation.

“These are intended to be the last major outages at Yallourn to ensure the station plays its role in keeping Victoria’s electricity supply reliable and affordable over the next five years as the state undergoes a transition to renewable energy,” Mr McIntyre said.

The investment will also cover an increase in power station maintenance work while generating units are unavailable to ensure the reliability and performance of the entire Yallourn plant site.

“We know this program of investment is also important to the Latrobe Valley economy. An additional 800 local maintenance workers will be on-site throughout each major outage, with much of the overall investment supporting local businesses and employment,” Mr McIntyre said.

Mr McIntyre was proud to say that EnergyAustralia has just appointed six additional apprentices and an environmental graduate, who will gain experience at the Yallourn power station over the next few years. These new appointments come after EnergyAustralia’s partnership with Federation University Gippsland to provide scholarships and industry placements.

From the $400 million dollar investment, Mr McIntyre said, “We’re also continuing to support our people at Yallourn as we plan for the period after the station’s closure. This includes our $10 million program to provide transition support for employees along with ongoing planning for the safe rehabilitation and transformation of the Yallourn mine and power station site so they become an asset for the local community.”

EnergyAustralia is exploring all avenues to determine the value of repurposing the Yallourn plant for other uses after Yallourn is decommissioned and remains committed to investing in the Latrobe Valley.

“EnergyAustralia will continue to invest in the Latrobe Valley and its role in Victoria’s clean energy future. Our gas power station at Jeeralang will remain to provide flexible capacity to support renewables and with the Wooreen project, we are progressing plans to build Australia’s first utility-scale 350MW battery which will provide power for around 230,000 Victorian homes over a 4-hour period,” Mr McIntyre said.