Anaerobic Digestion: gaining value from waste
Human waste is a fact of life - and more efficient, less carbon-heavy solutions for its safe, effective treatment become more pressing as populations grow.
For years, the water industry has used anaerobic digestion (AD) - a process where microbes break down biodegradable materials in the absence of oxygen - to convert sewage sludge into agricultural fertiliser and biogas to generate heat and green energy.
A major challenge is to improve the efficiency and effectiveness of the AD process to help sewage infrastructure keep pace with the increasing volumes of waste water flowing through sewage systems.
AD is also playing an important role in reducing the environmental footprint of agriculture by converting animal waste and crop residues to energy and high value compounds.
It is also the UK government's preferred method for capturing resources from food waste, which will be collected separately from other household waste by 2023, further reducing landfill and greenhouse gas emissions.
The BioVale team at York’s Biorenewables Development Centre has been promoting AD through their special interest group which advises members on best practice and current research, builds connectivity between stakeholders and supports innovation.
The System-60 Project, led by Professor James Chong at the University of York, aims to boost AD performance by improving our understanding of the performance of the AD processes.
Launched in 2016 by Yorkshire Water, the Royal Society and researchers from the University, this pioneering project uses a set of 60 five-litre automatically-fed, temperature controlled anaerobic digesters housed in the University’s Department of Biology to examine the microbial communities that drive AD. Results from this analysis can be applied to improve AD performance and produce different and higher value products from waste.
A pilot-scale AD rig at Yorkshire Water’s nearby wastewater treatment works at Naburn validates the science developed in the laboratories with the aim of supporting operational changes across Yorkshire Water’s digester facilities.
The project builds on Professor Chong’s research expertise in anaerobic microbes, some of the first forms of life to inhabit our planet, and a key component in the anaerobic digestion process.
Further investment from Yorkshire Water and the University has helped develop System-60 infrastructure further by establishing the University’s Centre of Excellence for Anaerobic Digestion (CEAD).
Since 2016, BioVale's AD Special Interest Group has promoted new AD-related technologies and encouraged networking with 430 members and has catalysed 45 projects following over 350 individual introductions.
These projects have the potential to transform AD performance, strengthening the University's bio/circular economy research portfolio, and contributing to the region’s aspiration to become carbon neutral.
Professor Chong said: “The water industry has recognised that what ends up in the sewer is a bioresource. Yorkshire Water has demonstrated a long-term vision in the potential of AD by investing in these facilities and by providing us with exceptional access to their AD operations.”
Professor Chong is a molecular biologist using methanogens to understand anaerobic digestion.
Find out more about Professor Chong’s research in this YorkTalks presentation
Energy down the drain: how microbial communities can aid us in turning wastewater into low carbon energy
Developing hemp as an industrial crop
Hemp is an incredibly versatile crop with a variety of applications in many industries. It offers environmental benefits as a fast growing ‘break’ crop that improves soil health, and is highly efficient at capturing carbon.
Researchers at the University of York and Biorenewables Development Centre (BDC) are working with industry to develop a strong portfolio of hemp research and development.
However, for hemp to become a successful, widely-used industrial crop, there are still barriers to overcome. Hemp seed oil is rich in polyunsaturated fatty acids which become unstable during food processing and cooking and it is not currently a major UK crop, despite offering a wealth of environmental and economic opportunities.
Research at York, led by Professor Ian Graham, FRS has focused on two different approaches to overcoming these obstacles and developing hemp as an industrial crop.
The first is to create a new variety of hemp that contains oil which is more stable. This new variety of hemp, developed without using GMO technology, is the first to be registered on the basis of altered seed oil content, and has much to offer the food industry and sustainable agriculture.
Researchers discovered the genes responsible for production of the different types of fatty acids in hemp seed oil. They then activated a key gene that resulted in hemp seed oil containing 75 per cent oleic acid, creating a more stable hemp seed oil with a longer shelf-life.
Secondly, the HEMP-30 project seeks to understand and resolve the barriers to industrial scale-up of hemp growing for the UK. This will lead to new opportunities for farmers, while supporting the development of high value, skilled jobs and providing low carbon industrial products.
A new variety of hemp has been registered in the UK. Its seed oil is seven times more stable than conventional hemp seed oil at 4°C, and five times more stable at 20°C. This product is undergoing commercial evaluation for food applications by a North American company with a view to commercially licensing the US and Canadian patent. The US patent is to be licensed to a North American company and a partnership agreement is being agreed with a UK seed company.
Industrial hemp is a low maintenance crop that is very attractive as a rotation crop for oilseed production in the UK and other countries in Northern latitudes. The results of the HEMP-30 project input into the UK Government’s Biomass Feedstocks Innovation Programme and could see hemp established as a major UK crop.
Ultimately, HEMP-30 aims to increase the amount of industrial hemp grown in the UK 100-fold to 80,000 hectares, establishing hemp as a major UK crop, used in a range of applications in food, fuel, construction and pharmaceuticals.
Professor Graham’s interests include how plants make and break down metabolites, how these processes are controlled and how they impact on plant growth. Professor Graham is academic lead for the BioYorkshire project.
Dr Ross has over 20 years university R&D laboratory and management experience working primarily on the development of novel plant varieties including a wide range of fibre, oilseed and medicinal plant species using fast-track breeding methods. He is director of the Biorenewables Development Centre.
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