Supporting the pathway to creating bioplastic and biofuels at pulp mills

Story by Tony Kryzanowski

Alberta's pulp mills generate methane and methanol as byproducts from their pulp production processes. These byproducts can be converted into higher value, biodegradable plastics, biofuels and specialty chemicals.

A University of Alberta research team is showing industry how to add value to these unavoidable byproducts using micro-organisms called methanotrophs.

Alberta Innovates has provided $340,000 through its Alberta Bio Future program to the U of A team to develop processing strategies that industry can adopt to divert their methane and methanol waste streams economically to create bioplastic granules and liquid biofuels.

Bioreactor facilities to produce these biomaterials can be built alongside pulp mills. Application of the micro-organism conversion technology requires minimal pre-treatment of the waste streams before they enter the bioreactors, offering industry significant cost savings in the manufacturing process.

We are looking at a waste stream that can produce biodegradable plastics that don't stay in the environment forever."

Dr. Dominic Sauvageau

Converting these byproducts, methane in particular, also delivers a notable environmental dividend, as methane has a global warming potential 28 to 36 times greater than carbon dioxide, based on a 100-year timeframe.

Researchers hope to have a pilot plant demonstrating the methanotroph technology within two years and are looking for Alberta industry partners. The technology has already been proven in other applications.

Finding alternative value streams for Alberta's forest sector within existing pulp mills can create greater value and utilization of renewable natural resources. This work could give the forest sector another revenue stream as well as reducing greenhouse gas production.

Dr. Dominic Sauvageau is an associate professor of chemical and materials engineering at the U of A and is collaborating on this project with his biological sciences colleague, Dr. Lisa Stein. He says this technology using methanotrophs is an economically viable alternative to byproduct management at pulp mills. It also provides an opportunity to produce biofuels without the raw material coming from a potential food source. Finally, the production of these bioproducts has a lower carbon footprint than production of plastics and fuels from petrochemicals.

"Our research work here is focused on optimization, finding conditions and engineering a process that makes these bacteria efficient, both at feeding on the methane and methanol and also at converting them into higher-value products," says Sauvageau. "We expect to produce about one quarter tonne of product from one tonne of feedstock."

This conversion technology can also be used by companies in the petroleum sector that are producing surplus amounts of methane and methanol.

"There has been growing interest in the application of this technology and we have been able to expand and accelerate our research because of the initial and supplementary financial support offered to us by the Biorefining Conversion Network and Alberta Innovates," says Sauvageau.

He adds that single-use, petroleum-based plastics and their tendency to linger in the environment for centuries is a significant global concern, fuelling interest in the production of completely biodegradable plastic alternatives.

"We are looking at a waste stream that can produce biodegradable plastics that don't stay in the environment forever," says Sauvageau. "On the biofuel side, there have always been some issues attached to it related to food versus fuel (in terms of the feedstock used). Application of our technology is entirely different, as we are starting with inexpensive and non-food feedstocks like methane and methanol to produce a higher-value fuel."

Sauvageau says his team is focused on production of both bioplastics and biofuels to provide industry with opportunities to supply multiple markets. That way, not all mills are producing a single compound where they are competing against each other.

"We are looking at opportunities to create a whole array of products," Sauvageau says.

For more information about the Alberta Bio Future Program, visit the program page.

This story is reprinted from the Logging and Sawmilling Journal.