8 Mar 2023

Processing forestry slash on-site an immediate solution - Scion chief executive

2:31 pm on 8 March 2023
In Tairāwhiti, farmers near Tolaga Bay saw forestry slash and land damage from winds and heavy rain as a result of Cyclone Gabrielle.

Forestry slash is seen near Tolaga Bay in Tai Rāwhiti following Cyclone Gabrielle. Photo: Supplied / Bridget Parker

An immediate solution to solve the issue of destructive forestry waste - or slash - is available and implementing it must be accelerated, says a forest research organisation.

During Cyclone Hale and Cyclone Gabrielle, massive volumes of forest debris ended up blocking water channels, smashing into bridges and farm infrastructure and flowing over farmland in Tai Rāwhiti and Hawke's Bay.

Scion chief executive Julian Elder was making the comment in the wake of the announcement of a ministerial inquiry into land use practices on highly erodible land.

"The organisation has been working with government, industry, and local communities to better understand and prepare for the risks that come with managing forests and land use change in highly erodible land under a changing climate," Elder said.

"It is clear that our forestry and land management practices in high-risk areas will need to change. How that transition can be implemented, while supporting local communities, needs to be a key focus of the inquiry," he said.

"We look forward to sharing insights from that work with the inquiry panel so we can help accelerate solutions."

But there was an immediate solution to forestry slash in the form of a portable, container-sized mini-factory to process forestry waste on-site, turning it into new high-value products, Elder said.

To date the technology, which is available, has not been seen as financially viable, but "when you factor in downstream impacts, if you leave it [slash] behind with logs and large woody items, then it might change the economics of this", he said.

The climate change challenge was driving the move away from fossil fuels, he said.

"We're going to need more and more biomass for producing energy fuels, materials, chemicals in a sustainable way, so there's an opportunity to move to using the slash," he said.

"One of the areas that we've been working on for a little while is: what can we do in terms of distributed manufacturing?"

The quickest option was to chip the slash and further process it on site or transport it elsewhere and make it into valuable energy materials or chemicals, Elder said.

Manufacturing around the world was now able to be done on a smaller scale than previously, he said.

"That's because the technology has now allowed us to do things economically at a smaller scale, and that's in relatively recent times," he said.

"The big advantage of the sort of processing we're talking about in this biomass field is that it has lower temperatures and pressures than you have to use for petrochemicals, so it's very viable to effectively put a processing plant in a container."

Chipping was an easy first step which let processors consider all sort of options, including the possible transportation of the chip to a central processing plant, he said.

"But certainly our work is looking at the opportunity to have processing plants in the container and on-site, where they're actually producing chemicals or fuel."

He could not put a time frame on setting any mini factory up but said it would be "relatively quickly", and "it always surprises me how much ingenuity there is in New Zealand".

Elder said government money would be needed to get the initiative started.

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