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

Periodic Reporting for period 1 - SWEETWOODS (Production and deploying of high purity lignin and affordable platform chemicals through wood-based sugars)

Reporting period: 2018-06-01 to 2019-11-30

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 lignin. Sugars and lignin can be further processed and converted to high-value biomaterials capable of replacing fossil-based chemicals in a wide range of products. The project, which uses wood processing residues as a feedstock, will lead to wood-based biomaterials being produced on an industrial scale for the first time. 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 and depolymerised lignin for a range of novel applications, namely elastomer foams for tube insulation, rigid polyurethane foam panels for insulation and polymer compounds intended for injection molding; 4) Produce high-purity sugars - glucose, fructose, xylose and 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 initial period covering the first 18 months of the project has concentrated on SWEETWOODS flagship plant building. The civil works have been finalized and the site has been handed over for the technology platform, piping and equipment installations. The pre-treatment and hydrolysis processes have been optimized in the pilot-scale and are ready for up-scaling. Materials - sugars, crude lignin and depolymerized lignin - have been produced in pilot-scale. The end-use case owners have tested the applicability of the sugars and lignin for their applications in the lab-scale. Three applications are now ready for up-scaling as soon as larger amounts of materials will be produced by SWEETWOODS plant. Two life cycle analysis studies have been performed for microchipped wood and enzyme production. Also, the health and safety studies have been initiated by defining methodology, identifying the study scope and risks.
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 compared to the conventional pulp mills and ethanol biorefineries, the main difference of SWEETWOOD is related to the fact that over 95 % of the feedstock is converted to the main products and only 2 % lost as CO2 from hydrolysis and 2-3 % recovered via anaerobic digestion.
During the first period, a tailored hydrolysis solution was optimized to work with the SWEETWOODS specific feedstock and pre-treatment method. After optimization, Metgen’s enzymatic hydrolysis solution works at beyond state-of-the-art performance level at high biomass consistency. Also, Metgen’s METNIN™ technology fractionating lignin enzymatically has been finalized. It is superior to the state-of-the-art in terms of high yield, low operational costs and capital expenditure requirements, and high functionalization of output. At the end of the project, all the lignin end-use cases (elastomer foams for tube insulation, rigid polyurethane foam panels for insulation, polymer compounds intended for injection molding) and bio-based IBN utilizing second generation sugars are expected to be novel and beyond state-of-the-art.
3D model of the SWEETWOODS flagship plant