Learning About Lignin at CRIBE

The continued emergence of the Canadian bioeconomy has increased the need for homegrown solutions for pushing the agenda forward. As provinces work to expand opportunities for research and development for a variety of bioenergy solutions, the establishment of the Centre for Research and Innovation in the Bio-economy in Thunder Bay, Ontario, has provided the needed funding for a new lab that looks to learn more about the marketable value of lignin.

An overhead view of the lignin pilot plant operated by FPInnovations at the Resolute Forest Products mill in Thunder Bay.

In June of 2011, CRIBE announced that it was providing $850,000 for the establishment of a world-class lignin lab and demonstration plant at the Resolute Forest Products (RFP) mill site (formerly AbitibiBowater) in Thunder Bay. In addition, Natural Resources Canada provided $500,000 in funding for the project, which is being run by FPInnovations (FPI).

The demonstration plant is the first facility of its kind in North America. The plant has been directly integrated into the kraft mill process at RFP. Testing and evaluation of lignin is done in the FPInnovations lab onsite, with further testing and evaluation of lignin and its product applications at other FPI labs as well with various research and commercial partners.

Lignin, once it has been extracted from a black liquor sample, undergoes a series of tests to determine what its best product application is.

Part of the work that needed to be done in advance of constructing the demonstration plant was to determine an effective system for lignin extraction based on the kraft mill process already in place at Resolute.

“In our process, the lignin precipitates from the black liquor as a solid when the black liquor is acidified,” said Kirsten Maki, associate research leader for the Bio-Economy Technology Centre. “The resulting slurry is sent to a filter press, where the lignin solids are trapped in the filter while the remaining black liquor passes through the filter media. The lignin is then squeezed, washed, and dried with pressurized air, and is discharged as a clean cake of lignin at around 60% solids. This cake can be dried further and then crushed, ground or pulverized, depending how fine a product is desired.”

One of the key reasons for linking the demonstration plant directly to the kraft mill process is the production of lignin to meet the growing demands of end users. The initial production capacity is 100 kilograms per day, which has already been met by Resolute.

As a result of the current lignin resources made available from the demonstration plant, over 25 organizations from across Canada, the United States and a handful of international partners have already received samples of the lignin for use in product development.

“Our largest order to date, approximately two tonnes, went to a phenol formaldehyde resin manufacturer – the lignin can replace some of the phenol in the formulation,” said Maki. “The expectation is that resin will be among the first higher value/higher volume uses of lignin derived from kraft black liquor (versus using lignin for its fuel value).”

Collecting Samples
Smaller samples of the lignin created at the demonstration plant are being used in the research conducted at the FPInnovations black liquor and lignin evaluation lab located on the same site. The large quantity available from the extraction process at RFP will allow for in-depth testing, helping to determine variations in lignin quality based on the type of wood and the process by which the lignin was extracted.

Black liquor samples are sent to the FPInnovations Lignin Lab from across Canada by companies looking to understand the best end-use for the product.

The lab and pilot plant also has the capacity for accepting black liquor and lignin samples from across Canada and around the world. Those samples are voluntarily sent by manufacturers looking to understand the characteristics of the lignin to determine the best end use for the product. Currently, lignin is being evaluated by companies across Canada as an alternative to petroleum-based chemicals used to make products such as carbon fibre, pharmaceuticals, resins, rubber additives, and thermoplastics. As researchers are able to provide thorough evaluations of lignin samples from a variety of wood species, these companies will be able to gain a greater understanding of the lignin they will need in order to produce the highest quality product. At the same time, researchers at the lab also gain that same knowledge, which will allow for the creation of an extensive database of information for comparing lignin samples from around the world.

The tests being run on the black liquor and lignin samples are being conducted by a four-member team of researchers from FPInnovations, and supported by the work of graduate students and post-doctoral fellows. Thanks to a partnership between FPInnovations and the Lignoworks network, in co-operation with The Natural Sciences and Engineering Research Council of Canada, students from major universities across Canada have access to the lab to assist graduate-level research being done in  relation to both the extraction process and lignin-based product development.

The research and development that will result from the work being done at the lab will provide significant benefits for the bioproducts industry in Canada. The constant, available supply of lignin will help the industry move from the production of lignin-based products at the laboratory sample level to a much larger scale. The evaluation of the demonstration plant’s performance will help FPInnovations, and its engineering partners at NORAM, understand the design requirements necessary to increase the scale of lignin production. Classifying, researching, and evaluating lignin from different extraction processes and wood samples will give producers a real understanding of the most effective end uses for those same lignin samples.

The world-class lab and demonstration plant at RFP in Thunder Bay, in partnership with FPInnovations, has the potential to provide the needed research and development to vault Canada to the forefront of the global bioproducts industry.