Green Day Energy trial to turn prickly acacia to biomass soon to start

Green Day Energy founder Brad Carswell said they would be on site in Richmond from September 5 to put together a torrefaction pilot plant, followed by five days work pulling prickly acacia out of the ground from September 8.

That will be followed by another five days of grinding the raw product up into chips, after which an estimated 150 tonnes of torrified product will be produced from 300 tonnes of raw biomass, for use as a testing sample for a high energy user in the region.

Mr Carswell described it as stage one of the $5m commercial torrefaction plant planned for the town, saying it would cost around $400,000 to implement.

He also said that because of supply chain issues they'd been unable to secure the machinery originally intended for the project, and they were instead going to chain pull the 10,110ha town common and 20 Mile reserve agreed to in a Memorandum of Understanding signed in July 2021.

The plan is to windrow the timber then chip it all in the paddock before trucking it back to the pilot plant for processing.

"To do 25,000 acres, (which is) what we want to do when we officially get going, that could take us five to eight years to clear that part alone," Mr Carswell said.

"We've got to get our processes and issues like that up and running, so we know what tonnage and get it back to our plant, so there's a little more strategy to go yet.

"We've got to find our feet, do a small amount first and build it up incrementally."

The end product will be used as a sample for an un-named high energy user in the region.

"We've had meetings with them and we've got to go through due diligence to see what the burning rate is that they burn it for - it's for emissions reduction," he said. "We believe (the trial) will be successful because torrification has a calorific value of 24 gigajoules a ton, which is better than Callide thermal coal."

Mr Carswell is promoting the venture as the biggest environmental project in Australia, saying it would meet the triple bottom line.

"We will have an economic benefit, a social benefit bringing workers back to the region, and also an environmental outcome," he said.

"We're going to employ people, and we don't want to employ single people, we want to target families to come back to the regions.

"If we give them secure work, secure pay and a lifestyle, we'll attract families to the region."

Western Queensland natural resource management group Desert Channels Queensland has queried whether enough attention is being paid to regrowth possibilities as commercial prickly acacia harvesting operations gather momentum in the region.

Operations manager Simon Wiggins said that when the mature tree was harvested, it provided an opportunity for the seed in the soil to germinate.

"If it's not controlled properly at that initial stage, then the problem can be far worse than it started with," he said.

He also questioned the commercialisaton of a declared weed, but Mr Carswell responded that the simple fact was, "that until there's an economic benefit, prickly acacia will never come out of the ground".

"Now, where Desert Channels Queensland operates out of, they contain it.

"We want to go there and remove the root, ball and all, and rehabilitate the Mitchell grass downs and we're in talks with the state government and council about making sure the prickly acacia doesn't come back.

"We know it's going to come back, it's as simple as that, you don't have to have a PhD but it's how we contain it."

Mr Carswell said they planned to poison the newly germinated seedlings once they were above the ground, as well as use growth inhibitor pellets.

"It's going to be an ongoing program to eradicate them," he said. "We won't get it in one hit because those seeds lay dormant in the ground for 7-15 years. We want prime grazing land to come back to what it was."

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