Omnivore: a multi-feedstock biorefinery

Lead Research Organisation: University of York
Department Name: Biology

Abstract

There is a growing market for sustainable lignocellulosic bioethanol produced from crop residues and waste materials. Producing biofuels from these materials is challenging because none are typically available in appropriate quantities in a single location to support processing at the scale needed to cover capital investment. In addition, conventional processing of lignocellulosics produces fermentable sugar concentrations that are too dilute for effective fuel production, and overcoming this through complex processing or evaporative concentration is expensive. The Omnivore system will overcome the supply challenge by developing a feedstock agnostic lignocellulose processing system. Omnivore will overcome the sugar concentration challenge, by operating a hybrid system using first generation sugars to supplement the concentration of lignocellulosic sugars. The verifiable % of lignocellulosic biofuel will attract a double trading obligation credit, which will improve profitability.
 
Description We have identified conditions in which all straw species can be pretreated and digested with enzymes to yield high sugar concentrations for fermentation with lower enegy and enzyme inputs. We have found that waste paper and municipal solid waste (MSW) fibre do not benefit from thermochemical pretreatment. We carried out experiments to produce sugar solutions from mixed residue processing and ferment these to produce bioethanol. We found that yields from mixed biomass processing and fermentation were comparable to those carried out using a single feedstock, but there is no benefit from mixing the MSW fibre and paper with crop residues as the former do not require the thermochemical pretreatment required by the latter. Technoeconomic abnalysis of scaled up hydrolyses and fermentations showed that the only cost-competitive route to advanced bioethanol production using our methodologies was from working with MSW fibre. This is because the higher RED credits and gate fees could offset the cost of bioethanol production.
Work in this project has acted as a spark to initiate further work aimed at commercialising lignocellulosic technology. The understanding we gained from working at larger scalew and using technoeconomic analysis opened our eyes to some of the major cost barriers in commercialing lignocellulosic technologies. this has moved ust to work on two areas with higher value end products; namely,citric acid in a Newton Bhabha Reducing Industrial waste project, and bacterial cellulose production for textiles in a Follow-on Funding project. The realisation of the economic and environmental impacts of waste water from outr processes has caused us to radically rething the chemistries that we use and move to using combinations that result in a crop fertiliser by-product of considerable value instead of waste water requiring expensive disposal and treatment.
While the outcomes of the work could be considered rather negative, the learning from the work has had added value. The technoeconomic analysis revealed trhat waste water disposal is one of the most costly aspects of our proposeed pathway to bioethanol production. This has caused us to re-think our approach to biomass pretreatment (in particular) and develop methods whereby the products from this step may generate value rather than cost.
In addition, we have used the front-end (biomass processing) components of the techno-economic analysis to investigate potentially more cost-effective end products and this has led to a new focus on renewable cellulose production, which appears far more likely to yield a profitable outcome. We have applied for further funding to pursue this possibility.
Exploitation Route This work could underpin the development of a mixed feedstock biorefinery in the UK
Sectors Agriculture, Food and Drink,Chemicals,Environment,Manufacturing, including Industrial Biotechology,Transport
 
Description The work has brought us to a better understanding of how our academic work can translate into an industrial process. Prior to this project, we focussed on developing an academic understanding of the process necessary to convert biomass into useful products with a focus on sugars for fermentation, along with understanding the environmental impacts and potential benefits this can lead to in terms of reducing net carbon emissions associated with fuels. In this project we employed an industry consultant to work with us on techno-economic considerations, which brought home the realities of reducing our understanding into a commercial context. The technoeconomic analyses revealed that our processes were far from being commercially competitive with regard to current prices of fossil fuels and first generation biofuels. The studies also highlighted the aspects of the work that carried major aspects of the cost of our processes. The cost of enzymes, which had been the major area of our research, had (through that reasearch and that of others) become a less significant consideration. Instead, the cost of feedstock was the biggest factor (not surprising) followed closely by the amount of waste water generated in our processes, along with capital costs for the pretreatment technologies we were working with. This caused us to radically reconsider the approaches taken in pretreatments. The work also highlighted the potyential of using the biological fraction of municipal waste (BioMSW) as a feedstock due to its radically lower price. As a consequence, I initiated a discussion between Wilson Bio-Chemical (company involved in the project- providing BioMSW fibre) with Clariant, a company building second generation bioethanol plants. This led to Clariant successfully trialling Wilson's BioMSW fibre in their processes, and the two companies signing a memorandum of understanding to work together on developing a commercial process. I also introduced Wilson BioChemical to LanzaJet a company with a commercial process for converting bioethanol into sustainable aviation fuel. This helped lead to a successful bid by Wilson, Clariant and LanzaJet to carry out pilot trials for a process to produce bio-aviation fuel from BioMSW. The finding of Omnivore also led us to reappraise our approach to biomass pretreatment and this has informed subsequent developmengts in our Newton Bhabha Reducing Industrial Waste in India project.
First Year Of Impact 2021
Sector Manufacturing, including Industrial Biotechology
Impact Types Economic
 
Description Bio-Manufacturing textiles from waste
Amount £628,992 (GBP)
Funding ID BB/T017023/1 
Organisation Biotechnology and Biological Sciences Research Council (BBSRC) 
Sector Public
Country United Kingdom
Start 09/2020 
End 08/2022
 
Description Newton Bhabha Industrial Waste: Reducing Industrial Waste from Sugarcane Processing in India
Amount £711,828 (GBP)
Funding ID BB/S01196X/1 
Organisation Biotechnology and Biological Sciences Research Council (BBSRC) 
Sector Public
Country United Kingdom
Start 10/2018 
End 09/2021