The LignoForce System™: A process for the production of high-quality lignin from black liquor
FPInnovations and NORAM Engineering jointly developed the LignoForceTM system, a patented technology for the recovery of high-purity lignin from softwood, hardwood or eucalyptus kraft black liquors. The process was implemented in West Fraser’s Hinton pulp mill in 2016, Canada’s first commercial-scale lignin recovery plant.
This process can be used at kraft pulp mills to produce:
- more pulp in the case of mills that are recovery-boiler limited (by offloading the recovery boiler with respect to calorific and solids loading)
- high-quality lignin (acid form) for use as a carbon-neutral fuel in the lime kiln
- high-quality lignin (acid or base form) for sale to market for use in several medium- and high-value applications such as wood adhesives, dispersants, and as a bitumen substitute in asphalt.
LignoForceTM advantages
A unique feature of the LignoForceTM technology is the presence of a black liquor oxidation step prior to the precipitation of lignin by acidification with carbon dioxide, CO2. This provides several advantages compared to other processes for kraft lignin precipitation:
Reduced sulphur compounds are oxidized, eliminating sulphur odours. This improves health and safety during the processing of the precipitated lignin and provides an odour-free product.
Less CO2 is needed to reach the target pH for lignin precipitation since some alkali is consumed by the oxidation of sulphur compounds and carbohydrates during the oxidation stage.
The lignin cake produced from the oxidized black liquor filters easily. A single press is adequate for the initial isolation of the lignin cake and subsequent washing steps, which lowers the capital cost.
The LignoForceTM can produce at least two lignin products (lignin in acid and sodium forms). Several other intermediate lignin products can also be produced depending on lignin application requirements.
Evaluate technical feasibility at the LignoForceTM Thunder Bay demo plant
The technical feasibility of producing lignin from black liquor using the LignoForceTM system can be evaluated initially with small amounts of black liquor at the laboratory and pilot plant levels at our facilities in Pointe-Claire, Quebec. Further investigations can then be conducted on a larger scale at FPInnovations’ Thunder Bay demo plant.
Laboratory tests and demo plant trials generate data relating to black liquor processability through the various unit operations of the LignoForceTM system, lignin recovery yield, chemical consumption per kg of lignin produced as well as lignin product quality. These data can then be used by NORAM Engineering to provide accurate estimates on the capital and operating costs associated with a LignoForceTM lignin plant. Furthermore, the lignin produced during these evaluations can be used for product development purposes and/or commercial-scale lignin product trials.
FPInnovations’ Thunder Bay demonstration plant was constructed within Resolute Forest Products mill in Thunder Bay, Ontario. The plant is sized to produce up to 50 ODkg/day of lignin and operates on a semi-continuous basis. It offers the flexibility to test black liquors from external mills to produce kraft lignin in the base form as well as lignin in the acid form.
Lignin, a value-added product
In 2016, West Fraser Timber launched the first industrial LignoForceTM facility in Canada, in Hinton, Alberta. Initially, West Fraser began producing lignin for use as a replacement for certain glue components used in their plywood and fibreboard mills. Today, the plant can produce 10,500 tonnes of lignin per year, and as the list of end-user lignin applications grow, West Fraser continues to expand its lignin-based product offering.
Using lignin to substitute petroleum based-products reduces CO2 emissions and sequesters carbon. FPInnovations is also working on further reducing CO2 emissions by improving the overall efficiency of the process – this will also reduce costs and increase productivity.
Lignin is currently used by industry as a component in wood adhesives and foam insulation, as well as a dispersant in the textile and pesticide industries. Applications on the horizon include use as a dispersant in the concrete admixture and drywall industries, as well as a replacement of petroleum-based chemicals in the thermoplastics, asphalt, and carbon fiber industries.
Read our article on lignin to learn more.
Interested in learning more?
Through extensive knowledge in lignin-based product development, FPInnovations can help companies develop greener solutions by incorporating lignin into their products.
For information about lignin supply, contact:
- FPInnovations: 1 to 100kg of lignin
- West Fraser Timber: 100kg to thousands of tonnes
For quotations on the LignoForceTM system, contact NORAM Engineering.
