European Commission logo
English English
CORDIS - EU research results

Production and deploying of high purity lignin and affordable platform chemicals through wood-based sugars

Periodic Reporting for period 3 - SWEETWOODS (Production and deploying of high purity lignin and affordable platform chemicals through wood-based sugars)

Reporting period: 2021-06-01 to 2022-11-30

The SWEETWOODS project aims to develop a first-of-a-kind wood fractionation flagship plant in Estonia that uses sustainable hardwood biomass. The process combines innovative pre-treatment technology with enzymatic solutions to provide sugar recovery levels of over 90 % with exceptionally high-quality hydrolysis lignin. Sugars and lignin can be further processed and converted to high-value biomaterials for replacing fossil-based chemicals in a wide range of products. The SWEETWOODS project has six core objectives. It targets to: 1) Show the successful and profitable production - on an industrial scale - of high-purity lignin along with penta- and hexa-carbon carbohydrates from hardwood; 2) Use all main components of the biomass feedstock while minimising any diversion of carbon content streams to low-value uses; 3) Produce high-purity lignin for drop-in applications and validate depolymerised lignin fractions for a range of novel applications, namely rigid polyurethane foam boards for building insulation and polymer compounds intended for injection moulding; 4) Produce high-purity sugars - glucose, xylose and demonstrate production of derivates of those (fructose, glucosone) - for novel end-use cases, namely producing bio-IBN, xylitol and lactic acid; 5) Establish markets for lignin and novel sugar-based platform chemicals; 6) Evaluate the environmental and socio-economic performance of the SWEETWOODS plant process and of the developed products through a Life Cycle Sustainability Assessment, as well as a viability analysis.
The main milestone of the project has been finalization of the construction of flagship plant in Imavere, including Phase 1 (pre-treatment, completed already during RP2) and Phase 2 (all downstream processes). In the SWEETWOODS project, the Sweetwater’s Sunburst pre-processing technology has been upscaled first time to a flagship plant scale. An extensive optimisation of the Sunburst pre-treatment technology has been carried out in the project to demonstrate efficient production of high-quality lignin and cellulosic sugar products. Fibenol has actively cooperated with potential off-take partners and sent samples to them. Also, first off-take agreements have been signed for lignin and cellulosic sugars.

MetGen has developed new and more potent SUNO™ solutions for hydrolysis of biomass. The latest version (SUNO™ 400 series) matches the performance of the commercial reference (Novozymes Ctec2). The performance is matching in the head-to-head technical benchmarking with Ctec2 concerning glucose yield. In addition, the further work to improve TE is ongoing to provide the competitive solution to market. MetGen has conducted successful technology transfer campaigns to industrial scale for several of its key enzyme; cellulase (hydrolysis), pyranose oxidase (sugar conversion), xylanase (hydrolysis) and laccase (lignin depolymerization and biomass pre-treatment). For the Glucose to Fructose and Glucose to Glucosone conversions, MetGen has conducted scale up trials from lab to larger pilot. MetGen has also started the conceptual basic design and techno-economic assessment work for on-site enzyme production (OSM) case.

MetGen has developed the METNIN™ Technology to depolymerize solubilized crude lignin and fractionate it. For the METNIN™ process, the input capacity of 1000 kg has been reached when operating in a fed-batch mode. MetGen has expanded METNIN™ process and downstream process towards productization, and developed two specific products, METNIN™ SHIELD for fibre-based packaging applications and METNIN™ NANOPolyol for rigid PU foams. In addition, MetGen has sent depolymerized lignins to end-user partners, namely Tecnaro, Recticel and Armacell.

The crude and depolymerized lignin have been successfully tested by TECNARO in injection moulding compounds. The injection moulding compounds having SWEETWOODS crude lignin as a main component has been produced in hundreds kg scale. The SWEETWOODS crude lignin is odourless, and it has shown very good performance and material properties in injection moulding compounds.

Recticel has characterized and compared the properties of the different batches of depolymerised METNIN lignins. Lab scale rigid foam samples were made here, showing properties comparable to the reference. So far, the initial target to replace 40 w% polyol by depolymerised lignin has not been achieved, but the development work continues with the different types of lignin from the SWEETWOODS project, this is with depolymerised lignin as well as METNIN™ NANOPolyol.

Armacell tested the depolymerized lignin in elastomer foam production process but decided to withdraw from the consortium during Reporting Period 3.

Global Bioenergies (GBE) has developed and patented an alternative protocol for producing bio-IBN (2-step “high purity” production). The new protocol was first validated by lab scale tests, then at pilot scale and finally at pre-industrial scale. Improved performance was demonstrated compared to the old protocol.
The suitability of SWEETWOODS sugar hydrolysates have been validated also in fermentation-based production processes of lactic acid and xylitol.

2B has assessed the fractionation process from the sourcing of raw materials to the final products by means of the LCA methodology. In addition, some end-user applications were also evaluated, and the results were compared with fossil-based alternatives. LCA results are promising but further investigation is required.
The reduction of ‘waste’ from a biorefining operation by at least 80 % compared with the state-of-the-art remains a feasible target. It is still expected that over 95 % of the feedstock is converted to useful primary products and only 2 % lost as CO2 from hydrolysis and 2-3 % recovered via anaerobic digestion.

In the SWEETWOODS project, the Sunburst pre-treatment technology has been upscaled first time to a flagship plant scale. The Sunburst technology fractionates biomass into its basic components faster and more efficiently than any other technology available on the market. The high purity cellulosic sugars and lignin produced by SWEETWOODS flagship plant can replace fossil products in a range of application areas.

MetGen has introduced the first of its kind of METNIN process to produce enzymatic treated lignin, including downstream processes. The METNIN process is scaled up to industrial scale by the end of the project. In addition, MetGen has successful discovered, developed, and scaled up several new enzyme prototypes and variants. The glucose to glucosone production with Metzyme PURECO Oxidase will be demonstrated in the larger pilot scale trials (TRL 7) by the end of project. The glucose to fructose production with Metzyme PURECO Glucose Isomerase will be demonstrated in ton-scale (TRL8) by the end of the project.

First time, the bio-IBN has been produced successfully in m³ scale from second-generation sugars as a feedstock material. Global Bioenergies has further improved the yield of its isobutene process by dividing the process into two consecutive stages. This new patented process makes the manufacturing process more flexible and economically efficient.

At the end of the project, all the lignin end-use cases (rigid polyurethane foam panels for building insulation, biopolymer compounds intended for injection moulding) and bio-based IBN utilizing second generation sugars are expected to be novel and beyond state-of-the-art.
SWEETWOODS flagship plant in May 2021. Ton scale lignin and cellulosic sugars production has started
SWEETWOODS flagship plant in Nov 2022.