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Flexible Superheated Steam Torrefaction and Grinding of Indigenous Biomass from Remote Rural Sources to Produce Stable Densified Feedstocks for Chemical and Energy Applications

Periodic Reporting for period 2 - SteamBio (Flexible Superheated Steam Torrefaction and Grinding of Indigenous Biomass from Remote Rural Sources to Produce Stable Densified Feedstocks for Chemical and Energy Applications)

Reporting period: 2016-08-01 to 2018-07-31

"The SteamBio objective was to demonstrate a mobile processing concept to efficiently pre-treat agro-forestry residues for use as flexible chemical and process industry feedstocks. From rural sources they would be upgraded and densified into uniform sizes so that they could be cost-effectively shipped to existing industrial sites. The enabling superheated steam processing (SHS) technology has been used in many industrial drying processes making use of its good heat transfer properties. Pilot SHS trials at up to 300°C was shown to torrefy various biomass. Typical torrefaction uses flue gases as heating medium, SteamBio only uses superheated steam as the heating medium using moisture evaporated from the biomass substrate. This results in clean uncontaminated outputs with potential to recover high value biochemicals released as ligno-cellulose is broken down, steam-stripped from the solid biomass and recovered in a condensate. SHS is scalable and best operated in a continuous steady state environment.

SteamBio successfully delivered a transportable 150kg/hour throughput industrial scale demonstration prototype. This was commissioned in Germany then shipped to Spain where it was seen by over 100 interested visitors. 6 different agro-forestry feeds were processed in tonnage quantities to produce stable torrefied biomass validated in combustion trials in an industrial lime kiln and, chemical rich condensates that are being evaluated for commercial opportunities.

Swedish University of Agriculture confirmed that SteamBio has a lower life cycle impact than conventional torrefaction. Commercial partners and Strathclyde Business School have developed a sustainable business plan with SteamBio Ltd incorporated as the primary vehicle for exploitation of the project results. The commercial partners are progressing with the demonstration unit in Spain to market validate the process outputs, securing further funds to transverse the ""valley of death"" into widespread market replication."
SteamBio involved 11 industrial and academic partners with a common purpose to create a viable business based on the SHS torrefaction of forestry and agricultural residues. A 150kg/hour throughput industrial scale demonstration unit was built, commissioned then demonstrated from November 2017 until July 2018. Demonstrations validated techno-economic performance in tonnage quantities of 6 different reference materials relevant to EU forestry and farming. Agricultural residues were olive and vineyard prunings, forestry was from various hardwood (beech) and softwood (pine) screenings. Demonstrations were shown to over 100 visitors from industry, research, investment, policy makers and the wider public with samples evaluated by third parties from industry and research. Torrefied solid was shown to effectively replace coal in an industrial lime kiln. Recovered condensates from the SHS process contain commercially relevant quantities of biochemicals uncontaminated by oxidative or other degradative reactions, they are of high purity but of mixed composition. Work is ongoing to optimise yield, separation and recovery of them.

The technical achievements are being progressed by the industrial participants’ commercial ambitions. These ambitions have evolved during project life; initially targeting “low hanging fruit”, with first sales for industrial bioenergy use, then using Organosolv processes to convert torrefied solid into biochemicals. The project showed that Orgnosolv process was not viable and that the bioenergy market on its own not valuable enough. Instead a larger economic potential was identified: during SHS torrefaction, ligno-cellulose is broken down, the chemicals released are stripped from the solid and collected in the condensate in a complex “biochemical soup”. The chemicals are clean, not contaminated by oxidative or other degradation reactions, though still needing to be separated and purified. The commercial partners are continuing to collaboratively work together post project: funding is being progressed to continue plant operation, enabling early revenue generation and progression from TRL7 demonstration to TRL9 industrialisation. SteamBio Ltd has been established as the primary vehicle to progress this commercial exploitation.
Bio-carbonisation not de-carbonisation: Instead of referring to “decarbonising” the economy, would it be more appropriate to focus on a greener form of carbon instead? Carbon has helped to shape the world we live, in fuels and in chemicals, but today it is primarily from unsustainable fossil sources; coal, oil and gas, causing environmental impacts in both extraction and use. Most EU use is imported with assorted concerns relating to security of supply. A more secure and sustainable future needs to use carbon from nature: “biocarbon”; to create biodegradable bioplastics, other biochemicals and renewable energy. However, it is important that biocarbon is sustainable with functionalities, availability and costs comparable to the fossil carbon it displaces.

Whilst biocarbon is an abundant natural resource, it is not always available in the appropriate condition or location. The infrastructure associated with fossil carbon has been developed over many years, based around centralised refineries. The biorefineries of the future cannot ignore these existing infrastructures. For biocarbon to become established it must be able to be stabilised, stored, transported and used with cost and functional equivalence to fossil carbon. This needs to be achieved without expensive plant upgrades.

How big is the market? The global chemical industry is worth $3 trillion, with biochemicals approximately $100 billion, a relatively small but growing proportion. At present these biochemicals are mainly “1st generation”, competing with available food supplies, not a sustainable long-term option, this has led to research and investment into “2nd and 3rd generation sources. The bioenergy market is more developed and is expanding. EU wood pellet use for energy generation has increased from 2.5 million tonnes of oil equivalence (Mtoe) in 2008 and is projected by European Biomass Association to be up to 32 Mtoe (80 million metric tonnes approx.) by 2020. As bioenergy demand has grown, issues have arisen which will also impact on 2nd generation biochemicals.

• Existing EU forestry resources do not meet market demand, resulting in significant imports and emerging competition for supply from East Asia. Concerns expressed on imported supplies include; ecological stresses where grown, environmental impact of shipments around the globe and competition from other users.
• There are abundant EU biomass resources not currently being used to meet this supply gap, e.g. there are an estimated 100 Mtoe of agricultural residues alone. However, these residues are not in a form that can be readily collated and is usable by a large scale bioeconomy. There is a need to be able to cost-effectively collate and present this material in a form that can be used.
• SteamBio targets this need.

Swedish University of Agriculture life cycle experts have verified that SteamBio is environmentally sustainable with fewer impacts than existing torrefaction. External evaluation of the condensate biochemicals have confirmed that they are of high purity, not degraded by oxidative or other adverse reactions. The need is to now define process to separate and purify these chemicals