Recovery and re-use of energy, water and nutrients from waste in the food chain (Redivivus)

Lead Research Organisation: Harper Adams University
Department Name: Animal Production, Welfare & Vet Science

Abstract

Summary

This project will study the ambitious task of redefining the role of a typical food and farm waste AD plant. Instead of just the production of biogas for heat and energy, and digestate for soil remediation, we will consider an AD plant as an energy, nutrient and water recycling facility. An approach to energy conservation will be developed in order to demonstrate a series of integrated technical solutions that have significant short-term economic and longer-term societal and environmental impacts, ultimately contributing to the Government's greenhouse gas emissions reduction targets and obligations under the European Landfill Directive. The UK has a highly successful agricultural industry and the food and drink supply chain is our largest manufacturing sector accounting for 7% of GDP and employing 3.7 million people. At 20% of UK purchase expenditure, food and drink is also our biggest consumer spending category. With imports of around 40% of the total food consumed (and rising) Britain is not self-sufficient in food production. Almost half of the vegetables and a significant proportion of the fruit eaten in the UK come from abroad. When combined together with home grown produce, and considered from a different food chain perspective, the UK wastes substantial quantities of food. Some estimates suggest that somewhere between 30-50% of all food grown and imported to the UK is destined to become food-waste. Food waste in the UK is the subject of environmental, economic and social concerns that has received widespread media coverage and met with a range of significant responses from the Government. Various objectives have been set, including the ambitious target of recycling food waste by increasing anaerobic digestion (AD) plants from 134 plants in 2013 to 1,000 plants by 2020. Simultaneously, it is estimated that primary energy production from biogas (in the EU-27) will increase by 382% between 2010 and 2020. Technologies will be investigated that could enable the following:

(a) Separation of CO2 from CH4 in biogas for higher calorific value heat and power, direct gas-to-grid injection and as a liquid gas farm vehicle fuel.
(b) Re-use of separated CO2 in CH4 heated greenhouses for enhanced crop growth, providing a cash-crop for AD operators/livestock farmers and (once commonplace for AD plants) reducing food imports.
(c) Coagulation and re-use of nutrients (P, N, minerals) in digestate in order to recycle fresh water and provide fertilizer for arable soils and greenhouse grown (hydroponics) crops.
(d) Use of crop bio-char as a carrier for recycled nutrients (P, N, minerals), transferring carbon from the atmosphere into useful carbon deposits in arable/horticultural soils, thereby taking it out of the short-term carbon cycle and into longer term non-atmospheric carbon pools.
(e) Modelling alternative approaches for the most effective recovery and re-use of energy and resources generated by AD taking into consideration societal, economic, and environmental factors and interactions with the national energy supply system.
(f) Understanding the economics and societal impact of the novel strategies advocated by Redivivus for energy and resource recovery.

The project therefore represents an opportunity to innovate an expanding AD market within Europe. The research required to support this change in concept needs a broad based, problem solving and multidisciplinary approach that considers societal as well as technological change. By using energy, nutrients and water from food waste to grow crops and reduce food imports at home, this project has added value in that it will contribute to ending the global food crisis that leaves millions worldwide starving and impoverished.

Planned Impact

Impact Summary

Scientists working in AD processing, biomass transformations, energy, water and nutrient recovery would benefit immediately from the novel concepts in this proposal. In the longer-term, the developments required in converting AD waste processing facilities to energy, nutrient and water recovery centres will help focus a developing industry in the UK. The rural economy will benefit from the successful implementation of this project. Livestock farmers and AD plant operators will benefit financially from diversification and enhanced profitability of their farm and AD business enterprises. Enhanced profitability of these enterprises will encourage other like-minded individuals to invest in similar diversification strategies. This will have financial benefits for the engineering and horticultural firms that design and construct AD plants and greenhouse facilities. Management firms that operate AD plants and firms dealing in locally sourced foods will also benefit from the availability of sustainably produced local produce.

1) Who will benefit from this research?
The interdisciplinary nature of the research and its systems approach necessitates close interaction with a wide range of industry partners, industry associations, academics, and public bodies. Consequently the project's research and outcomes will be quickly and effectively transmitted to a broad range of beneficiaries. These will include UK farming and horticultural industry and other commercial private sector beneficiaries such as UK and multinational AD plant manufacturers; recycling, energy conservation and chemical process industries; transportation/manufacturing industries; gas-to-grid and power generation energy companies. Policy-makers and governmental/public sector beneficiaries will include UK governmental departments with climate change policy agenda's and targets. Benefits to the wider public include environmental protection and sustainable use of natural resources. The project will improve public awareness of sustainability and waste disposal by linkage to locally produced foods. In the context of climate change, mitigation technologies for removing CO2 from the atmosphere are key challenges. The transfer of carbon from food waste into useful carbon deposits on bio-char offers promising possibilities. If done at scale, it provides an option to sequester carbon from plant material, taking it out of the short-term carbon cycle and therefore binding carbon efficiently and in a useful, productive, way into longer term non-atmospheric carbon pools.

2) How will they benefit from this research?
The livestock and horticultural industries contributes significantly (annual turnover £18.4 bn) to the UK's economy and the AD market is set to expand with estimates suggesting an increase from 138 plants currently in operation in the UK and 342 under development to a governmental target of 1,000 plants by 2020. Simultaneously, it is estimated that primary energy production from biogas (in the EU-27) will increase by 382% between 2010 and 2020 (increasing from 10.9 Mtoe to 41.6 Mtoe). This project therefore represents an opportunity to influence an expanding AD market within Europe. The project will benefit AD operators by enabling them to upgrade biogas to higher calorific value methane using a technology; estimated at 1/3 of the Capex of conventional scrubbing technologies. Additional returns are generated from the production of high-value cash crops using the heat, CO2 nutrients and water recycled from AD. The main UK glasshouse-grown crop market using supplementary CO2 was valued at £165 M in 2012. With the EU market estimated to be 10 times that of the UK. The project encompasses several technologies (biogas upgrading, electro- and bio- coagulation) that could provide maximum financial, economic and social benefit when implemented as a combined system.

Publications

10 25 50
 
Description Electrocoagulation can bring about significant recovery of phosphate (in a phosphate-rich sludge) from AD digestate
Exploitation Route We continue to work with Elentec and our research will contribute to commercialising their electrocoagulation offering.
Sectors Agriculture, Food and Drink,Chemicals,Energy,Environment

 
Description AgroCycle: Sustainable Techno-Economic Solutions for the Agricultural Value Chain
Amount € 454,012 (EUR)
Funding ID 690142 
Organisation European Commission 
Sector Public
Country European Union (EU)
Start 03/2016 
End 03/2019
 
Description BBSRC LBNet
Amount £74,801 (GBP)
Organisation Biotechnology and Biological Sciences Research Council (BBSRC) 
Sector Public
Country United Kingdom
Start 04/2017 
End 03/2018
 
Description Developing Local Bioenergy to North West Europe (BioenNW)
Amount € 90,000 (EUR)
Organisation European Commission 
Department Interreg : European Territorial Co-operation
Sector Public
Country European Union (EU)
Start 10/2014 
End 08/2015
 
Description Macrobiocrude: Developing an Integrated Supply and Processing Pipeline for the Sustained Production of Ensiled Macroalgae-derived Hydrocarbon Fuels
Amount £280,252 (GBP)
Funding ID EP/K014900/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Academic/University
Country United Kingdom
Start 02/2013 
End 07/2018
 
Title Bench-scale biomethane potential (BMP) 600mL bioreactors 
Description The bench-scale biomethane potential equipment consists of 20x600mL continuously stirred airtight bottles (bioreactors) which are placed in a temperature-controlled water bath and each bottle headspace is connected to a wet-tip flow meter via a CO2-scrubber. The gas flow thorough each wet-tip meter is continuously monitored by a computer program, which we have created. The computer program is able to generate an excel file which summarises the amount of biological gas production over time from each bioreactor. 
Type Of Material Improvements to research infrastructure 
Provided To Others? No  
Impact The beauty of having this device is the large number of manual labour hours which it will save our team throughout the project. Previously gas production from similar size bioreactors would have been measured once per day and this was a time consuming process. In addition, manual agitation was required to mix the bioreactor contents. With our new equipment we can now mix each bottle and accurately measure the gas production 24 hours per day and 7 days per week, with minimal human input. The equipment will firstly, contribute values needed for energetic modelling and secondly, provide digestate for practical research into nutrient recovery. 
 
Title Electrocoagulation equipment 
Description Our industrial partner Elentec Ltd has recently replaced the equipment that they originally provided for the project. Elentec Ltd has now commissioned a new state-of-the-art lab-scale electrocoagulation machine on-site at Harper Adams University. A new methodology has successfully been developed to demonstrate the suitability of electrocoagulation to recover nutrients from digestates.. 
Type Of Material Model of mechanisms or symptoms - in vitro 
Provided To Others? No  
Impact Currently we are using the new equipment and methodology to obtain data for the production of a manuscript and publication in an international journal. 
 
Title Lab-scale anaerobic digestion 25L bioreactors 
Description We are currently in the final stages of commissioning 4x25L semi-continuously fed bioreactor vessels. These bioreactors are designed to be fed a variety of feed substrates (e.g. algae, grass, food waste, cereal straws and slurry). The temperature and stirring of each bioreactor can be adjusted and are electronically regulated. Analysis of total gas flow, CO2 production and CH4 production are able to be continuously recorded and are downloadable via a purpose-written computer program. 
Type Of Material Improvements to research infrastructure 
Provided To Others? No  
Impact Operation of these bioreactors will be central to providing the data which is required for multiple aims and objectives of the Redivivus project. It is intended that the bioreactors will act as a highly controlled source of digestate which will be used for testing nutrient and water recovery by electocoagulation, biochar trickle filters and fertilisation of plant growth. In addition, the amount of energy recovered in biogas will be incorporated into a life cycle analysis of adopting these practices. 
 
Title Lab-scale electrocoagulation unit 
Description Elentec (our industrial partner) have provided and commissioned lab-scale electrocoagulation equipment for batch assessments. This tool is custom built and enables us to produce electrocoagulents with varying characteristics such as metal source, ion concentration and conductivity. 
Type Of Material Improvements to research infrastructure 
Provided To Others? No  
Impact This machine, in conjunction with using the lab-scale bioreactors which we have built, will allow us to quickly screen a wide range of electrocoagulation operating conditions for the recovery of water and nutrients from anaerobic digestion effluent. 
 
Title York Collaboration 
Description Our new collaboration with the University of York will enable us to apply their recently developed proteomic methodologies to the microbiome, in the digesters that have been developed for Redivivus work. 
Type Of Material Biological samples 
Provided To Others? No  
Impact Analysis of the microbiome of AD reactors using methodologies available at Your University. 
 
Description Collaboration with York University 
Organisation University of York
Department Department of Chemistry
Country United Kingdom 
Sector Academic/University 
PI Contribution Early career research funding has been awarded to Dr. Matthew Reilly (Value: £74, 801) by BBSRC LBNet for the Adconstraw project. The project will utilise anaerobic digestion equipment developed during the Redivivus project. The aim of Adconstraw is to combine metagenomic and metaproteomic analyses to determine the genetic code and protein synthesis which underlies the mechanisms of wheat straw hydrolysis by anaerobes native to sewage sludge.
Collaborator Contribution The lab-scale anaerobic digestion equipment that has been developed in-house for the Redivivus project will be used during a new spin-off academic collaboration with The Centre for Novel Agricultural Products at The University of York. New analysis will include proteomic and metagenomic assessments of anaerobic digesters.
Impact Multi-disciplinary collaboration with BBSRC funding adding value to EPSRC grant. Publication outputs expected.
Start Year 2017
 
Description Industrial collaboration with Elentec Ltd 
Organisation Elentec Limited
Country United Kingdom 
Sector Private 
PI Contribution Continuation of existing collaboration
Collaborator Contribution Continuation of existing collaboration. As of Jan 2018, Elentec Ltd have seconded a newly appointed member of staff to work alongside Matthew Reilly on the Redivivus project and activities related to their interests in electrocoagulation at Harper Adams University. Elentec provide a bench fee to Harper Adams University.
Impact Publications
Start Year 2018
 
Description Industrial collaboration with Elentec Ltd 
Organisation Elentec Limited
Country United Kingdom 
Sector Private 
PI Contribution Using electrocoagulation equipment made by the company to recover nutrients from digestate.
Collaborator Contribution Provision of electrocoagulation equipment. Planning experiments
Impact We have continued to work closely with industrial partner Elentec Ltd. New technical developments made during Redivivus have enabled us to plan sister projects in new areas. Additional funding is currently being sought for this further work. Likely to contribute to recovery of phosphate from digestate
Start Year 2016
 
Description Partnership with RCUK National Centre or Sustainable Energy Use in Food Chains 
Organisation Brunel University London
Department School of Engineering and Design
Country United Kingdom 
Sector Academic/University 
PI Contribution Contribution as Committee Member to National Centre
Collaborator Contribution Inclusion of Harper Adams University as a partner in the National Centre
Impact Networking
Start Year 2015
 
Description Production of biogas using gut anaerobic fungi and methanogenic Archaea 
Organisation University of California, Santa Barbara
Department Department of Chemical Engineering
Country United States 
Sector Academic/University 
PI Contribution Assist Prof Michelle O'Malley in gut fungal research, particularly in relation to isolation, characterisation and classification of gut fungi from herbivores at Santa Barbara Zoo. Mentor 2 PhD students. Assist in design and conduct of research projects.
Collaborator Contribution Conduct research on the molecular biology of gut fungi according to US grant applications.
Impact Several publications
Start Year 2010
 
Description Anaerobic Membrane Bioreactors for Wastewater Treatment and Energy Recovery (Southampton University) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact There were a large number of academics at this event who have significant experience in the field of wastewater treatment. In particular, this workshop was organised to discuss the latest advancements in membrane water treatments. The workshop helped us to learn more about alternative water treatment technologies, to those being investigated in the Redivivus project. We also received valuable technical advice and interest from the UK water industry, regarding the future development of biochar trickle filters during the Redivivus project.
Year(s) Of Engagement Activity 2016
 
Description Energy Expo Now 2016 (Telford) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact Harper Adams University had a stand at Energy Expo Now 2016. The event attracted 3000 farmers and landowners, with an interest in on-farm renewable energy projects. We were able to explain the aims and objectives of the Redivivus project to visitors and then receive their own opinions and relevant experiences.
Year(s) Of Engagement Activity 2016
 
Description Invited key notes speaker at the International Conference of Sustainable Agriculture, Yogykarta (Indonesia) 17-18 January 2017 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Invited key notes speaker at the International Conference of Sustainable Agriculture, Yogykarta (Indonesia) 17-18 January 2017
Year(s) Of Engagement Activity 2017
 
Description Meeting with Biorenewables Development Centre, York, 16th June 2016. 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact To plan for the LBNet Grant application
Year(s) Of Engagement Activity 2016