Bio-Refine: Recycling inorganic chemicals from agro- & bioindustry

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1 Bio-Refine: Recycling inorganic chemicals from agro- & bioindustry waste streams A.B. Ross 1, M.A. Carmargo-Valero 1, P. Williams 1, E. Meers 2 1 Faculty of Engineering, University of Leeds, Leeds LS2 9JT, UK 2 Faculty of Bioscience Engineering, Ghent University, Ghent B-9000, Belgium Abstract Bio-Refine is investigating the recycling of inorganic chemicals from agro- & bio-industry waste streams. The project is funded by the European Regional Development Fund under the INTERREG North West Region programme and will run for four years. The focus of the project will be towards closing nutrient cycles and developing sustainable resource management in the NWE region, both from an economical and ecological perspective. The NWE region with its high population density, intensive industrial and agricultural activity producing large amounts of residues, is an ideal testing ground for tackling these challenges. Therefore, Biorefine aims to follow a cross-sectoral and transnational approach involving all stakeholders and mobilising all knowledge available in the NWE region. The ultimate goal is to minimize residue flows and to economically valorise the minerals that can be recovered from these residue flows, thereby stimulating a bio-based economic growth and thus creating a win-win situation for both the environment and the economy in the NWE region. The project partners include groups from Belgium, France, the Netherlands, Germany and the UK. A key objective is to develop a UK nutrient platform to network industry, academia and poly makers to encourage the development of innovative technologies for the recycling and recuperation of nutrients from waste streams and to stimulate the development of trans-national networks with groups within the NWE region. Key words: Resource recovery, nutrient recovery, organic waste, closing-loop Introduction In the transition from a fossil based to a bio-based economy, it has become an important challenge to maximally close the nutrient cycles and migrate to a more sustainable resource management, both from an economical as an ecological perspective. Nutrient resources are rapidly depleting, significant amounts of fossil energy are used for the production of chemical fertilizers, whereas costs for energy and fertilizers are increasing. However, up until now this transition proved to be difficult to realise due to obstacles in (national) legislative systems, lack of integration of institutional and governance structures and lack of coordination between the actions undertaken by the different stakeholders and government levels. Although EU environmental legislation covers an increasing number of environmental aspects, there are still important challenges ahead to harmonise standards, techniques and markets in this area. The North West European (NWE) region with its high population density, intensive industrial and agricultural activity producing large amounts of residues, is an ideal testing ground for tackling these challenges. Therefore, Biorefine aims to follow a cross-sectoral and transnational approach involving all stakeholders and mobilising all knowledge available in the NWE region. To achieve this goal different stakeholder parties in the project area will be brought together, thus covering a large spectrum of mineral flows and offering a broad array of existing recycling applications. This interaction will create leverage of knowledge and will inspire regional applications, thus making a transnational benefit possible. The ultimate goal is to minimize residue flows and to economically valorise the minerals that can be recovered from these residue flows, thereby stimulating a bio-based economic growth and thus creating a win-win situation for both the environment and the economy in the NWE region. In this project we set out to bring together all stakeholders for the implementation of joint transnational innovative actions to minimize residue flows and to economically valorise minerals that can be recovered from these residue flows. By bringing stakeholders together

2 in a transnational knowledge platform, delivering pilot cross-sectoral applications of promising techniques on recycling and reusing of valuable minerals, and testing new systems for valorisation of recovered minerals, this project will provide improved and integrated responses to the technical, legislative and marketing challenges ahead. Sectors involved in the cooperation on this topic are: (a) Waste management and water purification organisations, both public and private, bringing together their expertise on techniques for recuperation of valuable minerals from waste and water; (b) The chemical processing industry bringing in line possibilities for reuse and valorisation of minerals that have been recycled (Cradle-to-Cradle, bio-based economy); (c) Agriculture, since several mineral residue flows have an organic base and mineral cycles can be closed relatively easily in this sector; It is therefore necessary to involve agriculture in a cross-sectoral approach; (d) Research institutes will be involved for knowledge development on this topic; In view of the cross-sectoral approach of this project, it will be necessary to involve different types of knowledge centres, covering technical, environmental as well as economical aspects. Policies regarding to use, transport, reuse, recycling and disposal of nutrients are directed from the EU level through various directives (i.e., nitrate directive, water framework directive, etc). However, implementing policies from EU directives is decided at regional or national level. As a result, the policies are often not harmonized with each other and conflicts between regions may arise. Also transports of nutrients in the environment are not limited by national borders. Therefore, a transnational approach is utmost desired for effective policy making and efficient business development. This project will provide an action-oriented approach to deliver applied technological solutions and transnational strategy development for improved recycling and valorisation of minerals that are valuable both from a natural resource as well as from an economic perspective. Nitrogen and phosphorus crises Although nitrogen appears as the largest single component of the Earth s atmosphere (78.1% by volume, 75.5% by weight), it is not a common element in the Earth s crust (Table 1). In the air, nitrogen forms a diatomic molecule (N 2 ) with a strong triple bond between the nitrogen atoms which makes it relatively inert. The inert nature of molecular nitrogen means that biologically available nitrogen is often in short supply in natural ecosystems, thus limiting plant growth and biomass accumulation; nevertheless, nitrogen is the fourth most abundant element in living organisms, after carbon, oxygen and hydrogen. Table 1 Nitrogen concentrations in the environment Location... Earth s crust Sea Water: surface deep ocean Fresh waters: unpolluted agricultural land Concentration ppm 0.1 ppb 0.5 ppm < 0.5 ppm ppm Atmosphere 78% Human body 2.5% Source: Cox, Naturally nitrogen is constantly fixed from the atmosphere either by the action of electrical discharges (lightning) or by biological processes. Molecular nitrogen (N 2 ) is fixed

3 biochemically as ammonia (NH 3 ) by specialized prokaryotic bacteria called diazotrophs; although ammonia is the first product of biological nitrogen fixation, it is nearly always assimilated as rapidly as it is formed (Postgate, 1998). A variety of free-living prokaryotes fixes nitrogen either under aerobic conditions (e.g., Cyanobacteria, Azotobacter, Azomonas, Azopirillum, Derxia, Klebsiella and Beijerinckia) or in anaerobic environments (e.g., Desulfovibrio, Clostridium, purple sulphur bacteria, purple non-sulphur bacteria and green sulphur bacteria) (Brock et al., 1994). There is also a group of bacteria working in symbiosis with plants (e.g., Rhizobium and Bradyrhizobium) that fixes nitrogen only when present in nodules or on roots of specific leguminous plants. Scientists estimate that biological fixation globally adds approximately 240 Mt of nitrogen to ecosystems every year, but very little of that figure goes effectively to food production (Gijzen and Mulder, 2001). The urgent need for food production has generated an intensive agricultural activity which requires huge amounts of nitrogen fertilizers obtained via industrial fixation. Industrial nitrogen fixation is carried out by the Haber Bosch process and represents 40 percent of the natural nitrogen fixation (Gijzen and Mulder, 2001). The world consumption of nitrogen fertilizers increased ninefold from 10 Mt N in 1960 to 91 Mt N in 2006, but even more alarming is the fact that in the same period of time it increased 22 times (from 2.3 to 63.7 Mt N/year) in developing countries (IFA, 2012) (Figure 1) N. fertilizer consumption, Mt N Word population, billions N. excretion, Mt N Time in Years World Developed countries Developing countries Time in years World population N excretion by humans Figure 1 Nitrogen fertilizer consumption and nitrogen excretion by humans (Camargo- Valero, 2008) Once that enormous amount of nitrogen fertilisers are released into soils as reactive forms of nitrogen (i.e., urea, ammonium and nitrate), only a very low fraction (10 15%) is finally incorporated into plant tissue; nitrogen is lost from soils through erosion, denitrification and leaching (Gijzen and Mulder, 2001). In the near future, it is expected that nitrogen fertilizer consumption will rise even faster not only to cover the world s growing food needs but also the emergent bio-fuel production based on crops such as corn, wheat, rice, soybeans, sugar cane and oil palm trees. For instance, 70 percent of the whole corn production in the USA (14 million tons) was used to produce 4,855 million gallons of ethanol in 2006 (Brown, 2006; RFA, 2008). In addition, nitrogen excretion by human beings in urine and faeces contributes increasing nitrogen discharge in domestic wastewater, considering that the human discharge is estimated at 4.75 kg N per capita per year (Mulder, 2003). If that figure is used to estimate the total human nitrogen excretion based on world population (see Figure 1), the current nitrogen fertilizer consumption by developed countries would correspond to the total nitrogen excreted by human beings. Therefore, domestic wastewater is one of the primary sources of

4 nitrogen in watersheds with low agricultural activity and it may become a major environmental problem (i.e., eutrophication of surface water bodies) due to many of the existing domestic wastewater treatment plants not being equipped to effectively deal with nutrient discharges only 5% of the total volume of wastewater receives tertiary treatment on global scale (Gijzen and Mulder, 2001). From a sustainable point of view, the presence of nitrogen compounds in wastewater represents a unique opportunity for nutrient recovery and reuse. After all, the provision of nitrogen fertilisers for food production is limited by the access to energy sources required for running energy-hungry, nitrogen fixation processes. Current global pleasure over reducing fossil fuel consumption, and the search for reliable renewable sources of energy to overcome future energy crisis, will also drive the development of sustainable nitrogen fertiliser production from low grade resources including wastewater, sewage sludge and food waste. As an element in the Earth s crust, phosphorus is a limited resource as its average concentration in the lithosphere is only 0.1 percent. Phosphorus is an unusual element as it is not found in nature as a free element due to its high reactivity. In the global market, phosphorus products refer to beneficiated phosphate rock with phosphorus pentoxide (P 2 O 5 ) content suitable for the production of phosphoric acid, elemental phosphorus and phosphorus fertilisers. It is acknowledged that phosphorus is a limiting nutrient for crop growth (Beus, 1979), as it is one of the least biologically available nutrients. In other words, the forms in which it exists in the biosphere are often unavailable for plants. Plants can only absorb the soluble inorganic form of phosphorus that appears dissolved in soil solution, also known as orthophosphates (Alley et al., 2011). Figure 2 Historical sources of phosphorus fertilizers used in agriculture globally (Cordell et al., 2009) As part of the Green Revolution triggered by research conducted between 1940s and the late 1970s and aimed to increased agriculture production around the world, the world production of phosphate rock increased substantially, beginning most markedly in the late 1960s (Figure 2). Morocco has the greatest reserves of phosphate rock, followed by Iraq and China (Table 2), which adds a geopolitical dimension to phosphate rock availability and trade. China s reserves may be much greater than indicated and well planned marketing strategies are controlling global trade, as China s phosphate rock exports have decline in the past years in order to secure internal demand for longer. Europe relies on imports to cover its demand on phosphorus fertiliser for food production.

5 Table 2 World phosphate rock reserves, reserve bases and production Mine production, tons... Reserves, Country tons... United States 25,800 28,400 1,400,000 Algeria 1,800 1,800 2,200,000 Australia 2,600 2, ,000 Brazil 5,700 6, ,000 Canada 700 1,000 2,000 China 68,000 72,000 3,700,000 Egypt 6,000 6, ,000 India 1,240 1,250 6,100 Iraq 5,800,000 Israel 3,140 3, ,000 Jordan 6,000 6,200 1,500,000 Mexico 1,510 1,620 30,000 Morocco and Western Sahara 25,800 27,000 50,000,000 Peru 791 2, ,000 Russia 11,000 11,000 1,300,000 Senegal ,000 South Africa 2,500 2,500 1,500,000 Syria 3,000 3,100 1,800,000 Togo ,000 Tunisia 7,600 5, ,000 Other countries... 6, , , World total (rounded) 181, ,000 71,000,000 Source: Jasinski, Production of phosphate rock is estimated to peak around together with a rising demand from a growing and hungry world population, trends towards more meat and dairybased diets, the need to boost soil fertility in some regions and demand for biofuels and other non-food commodities (Cordell et al., 2009). It is expected that after the global production reach a peak, phosphate rock reserves will decline (i.e., both in quantity and in quality) to levels that may transform phosphorus fertilisers into a luxurious commodity. State of the game: UK case The UK has a thriving farming sector that directly employs over half a million people and contributes ~0.5% of UK GDP ( 5.7 billion in 2011); around two thirds of production is devoted to livestock and one third to arable crops (Defra, 2012). The entire agri-food supply chain, from agriculture to final retailing and catering, is estimated to contribute 96 billion or 7% of gross value added; in 2012, the UK exported 18 billion of food, feed and drink (i.e., The UK is one of the top 12 food and drink exporters) and employed nearly 3.8 million workers in the whole food supply chain that includes agriculture and fishing. However, the infrastructure to support industry in applying science and technology to help modern farming and food production has declined over the past 30 years. UK agriculture s productivity growth has declined relative to our major competitors and our food supply chain relies more and more on imports. For instance, local food production still

6 depends heavily on imported mineral based fertilizers. The UK farming industry consumed 1,506 kt of fertilisers in 2010 (1,021 kt of N-fertiliser, 198 kt of P 2 O 5 and 287 kt of K 2 O), of which 90% of P- and 58% of N-fertilisers were imported (IFA, 2012). Agricultural activities such as fertiliser spreading or livestock management (diffuse pollution sources) contribute 60% of nitrate, 25% of phosphorus and 70% of sediments polluting UK water bodies (Defra, 2009). Also, they contribute 191 kt of ammonia (NH 3 N) and 87 kt of nitrous oxide (N 2 O-N) emissions per year to the atmosphere (Dragosits and Sutton, 2011), which ultimately leads to soil acidification, GHG emissions, aerosol generation (PM 2.5 and PM 10 ), and transboundary air pollution. Rising food prices and concerns about food security (the UK imports 40% of the total food consumed) and long-term sustainability of agriculture demand improved methods to retain nutrients in the soil and to recycle N and P from low-grade wastes. A vast quantity of secondary organic waste is produced annually, with agriculture the biggest contributor to organic residues. The application of bio-solids to land has enormous benefits although there is a need to better manage these valuable resources and reduce damaging impacts on ecosystems and human health. In terms of improving water quality, the EA has focused mainly on tackling point source pollution by implementing regulations such as the EU Urban Waste Water Treatment Directive and the Water Framework Directive. The UK water industry invested 13.9 billion between 2000 and 2010, to meet EU regulations regarding sewage discharges (point sources) (Defra, 2012a), but in the same period river water quality has not substantially benefited from such interventions, as current levels of nitrate and phosphate are still a matter of concern (National Audit Office, 2010). In fact, as pollution from point sources has been reduced, the impact of diffuse pollution (e.g., from agriculture) is becoming more evident and effective actions are urgently needed. Despite efforts from the EA and Defra to persuade the farming sector to recognise their responsibilities for diffuse pollution (e.g., Catchment Sensitive Farming programme, Defra), the sector s awareness of the problem remains low. Water pollution imposes not only environmental costs through its effects on aquatic life and human health (i.e., eutrophication, toxins from algal blooms), but also financial costs from the treatment of water for drinking. The cumulative cost of water pollution in England and Wales has been estimated at up to 1.3 billion per annum [6]. Ammonia emissions from spreading urea as a fertiliser and from slurry and manure are the largest source of acidifying gases both in the UK and Europe [7]. What s Biorefine contribution? European regions are facing the necessity to migrate to a sustainable resource management. However, there are still some important challenges ahead to harmonise standards, techniques and markets in this area. Biorefine provides as first a cross-sectoral and international network in order to create knowledge on the quantity and quality of the available nutrient resources in NWE region. It will provide an action-oriented approach to deliver applied technological solutions and transnational strategy development for improved recycling and valorisation of minerals that are valuable both from a natural resource as well as from an economic perspective. By bringing stakeholders together in a transnational knowledge platform, delivering pilot cross-sectoral applications of promising techniques on recycling and reusing of valuable minerals, and testing new systems for valorisation of recovered minerals, this project will provide improved and integrated responses to the challenges above. Through the networks from each of our partners and supported by a range of innovative communication tools, efficient dissemination of knowledge on this theme towards local, regional and European stakeholders will be made possible. This will support homogenisation of territorial disparities in legislation and policies that now hinder the development of a harmonised market of recycled minerals for high value application, thus making a transnational benefit possible. Ultimately, the wasting of finite resources and environmental

7 pollution will be greatly reduced and residues will get economic value, opening up new possibilities for sustainable and more bio-based economic growth and thus creating a winwin situation for both the environment and the economy in the NWE region. This project is delivered through five work packages (WP), each consisting of several actions. Every action targets a specific piece of work, which is both unique and linked with other actions within the package contributing to the project. Through the establishment of a (trans-) national Nutrient Platform (WP1), we will bring together policy makers, research institutions and industry, in order to explore the opportunities for nutrient recuperation and valorisation from waste streams. Based on this network, and a literature inventory (WP2), the best available techniques for nutrient recuperation will be selected, and pilot installations will be set-up (WP3). Also new strategies and synergies in cross-sectoral resource recovery will be explored and implemented in pilot scale installations and lab scale test (WP4). Life cycle assessments on the different nutrient recovery pathways will be assessed, and legislative bottlenecks for implementation will be identified and addressed (WP5). BioRefine runs until December, Biorefine partners Ghent University (Belgium) is one of the most important academic institutions for higher education in Belgium and coordinates this project. Two departments (UGent-LE and UGent- AE) are involved in this collaborative project, both from the Faculty of Bioscience Engineering. UGent-LE refers to the research team from the Department of Agricultural Economics, whilst UGent-AE refers to the research team from the Laboratory of Analytical Chemistry and Applied Agro-chemistry (ECOCHEM). UGeent-LE contributes with the economic and policy evaluation. Gembloux Agro-Biotech (Belgium) is the bio-industry unit from University of Liège, which specialised in the design of bioprocesses from the lab-scale to the pre-industrial scale. That research unit has also a good expertise in the area of waste management (e.g., landfill management, economic feasibility of biogas production, plant optimization of wastewater treatment systems, etc). In the context of this project, the bio-industry unit will be mainly involved in the design of optimized unit operation flowsheets for the recovery of nutrients from diverse streams of waste. Alterra (The Netherlands), a Research institute at Wageningen UR (a collaboration between Wageningen University and the DLO foundation) will lead the work on New strategies and synergies in cross-sectoral resource recovery. Alterra will also contribute/bring in two cases that will be studied and evaluated in Biorefine i.e, Phosphorus recovery from animal manure and Nitrogen recovery from liquid fraction of animal manure. The Bauhaus-Universität Weimar (Germany) has long lasting experience in the field of nutrient recovery from waste streams, especially P and N from digestates, as well as from wastewater. Embedded in a network of experts, agencies, NGOs and authorities a large pool of knowledge is available which contributes several aspects to the project. They are aimed at establishing a German nutrient platform will set the basis for a transnational cooperation on the field of nutrient recovery in the NWE region. In contribution to the improvement of regional capacities, the information they have about nutrient sources, pathways and techniques in Germany will be provided. Faculty of Engineering, University of Leeds (UK) will contribute by establishing a Universitywide platform on nutrients and develop national links through contribution to workshops and meetings in the UK. That feedback both to European networks already implemented and those new developed within this project. Leeds will contribute to actions on an assessment of hydrothermal processing routes for recovery of nutrients and will investigate the use of algae for nutrient recovery from waste streams.

8 Laboratoire Départemental d'analyses et de Recher (LDAR) France. LDAR contributes with the evaluation of some raw materials and products considering their physic-chemical and biological characteristics and potential as fertilisers and soil amendments, as well as the development and monitoring of a French nutrient platform and its links with European partners (Belgian, German, Dutch and UK platforms) Enerbiom (France) is an SME in the sector of biogas production. They design and construct biogas plants for farm waste and develop solutions for digestate treatment and disposal. Currently, their approach for recovering nutrient from digestate includes ammonia stripping where ammonia is volatilised and carried away in a stream of air and then it is absorbed in the presence of sulphuric acid, for the production of ammonium sulphate as nitrogen fertiliser. Acknowledgements: The authors would like to acknowledge the European Regional Development Fund, INTERREG, NW Region for co-funding this work under project BioRefine : Recycling Inorganic Chemicals from Agro- and Bio-Industry Waste streams. Contacts For further details on the UK nutrient platform or the BioRefine project, please contact the UK partners: Dr Simon Wilkins (S.A.Wilkins@leeds.ac.uk), +44 (0) , Faculty of Engineering, University of Leeds, Leeds LS2 9JT, UK, or visit the BioRefine web-site. Web site: REFERENCES Ashley K, Cordell D, Mavinic D (2011). A brief history of phosphorus: From the philosopher s stone to nutrient recovery and reuse. Chemosphere, 84, Beus A.A. (1979). The chemical composition and origin of the primeval continental crust. Physics and Chemistry of The Earth, 11, Brock T.D., Madigan M.T., Martinko J.M., Parker J. (1994). Biology of Microorganisms. (Seventh Edition). Prentice-Hall International, USA. Brown L. (2006). Appetite for destruction. FORTUNE. Europe edition, September 4, 154(4), 28. Camargo-Valero M. A. (2008). Nitrogen transformation pathways and removal mechanisms in domestic wastewater treatment by maturation ponds. PhD Thesis, School of Civil Engineering, University of Leeds, Leeds. Cordell D, Drangert J-O, White S (2009). The story of phosphorus: global food security and food for thought. Global Environmental Change, 19, Cox P. A. (1995). The Elements on Earth: Inorganic Chemistry in the Environment. Oxford University Press, Oxford. Defra (2009). The future of our farming. Defra, UK Defra (2012). Food Statistics Pocketbook Defra, UK. Defra (2012a). Waste water treatment in the United Kingdom 2012: Implementation of the European Union Urban Waste Water Treatment Directive 91/271/EEC. Defra, UK. Dragosits and Sutton (2011). The spatial distribution of ammonia, methane and nitrous oxide emissions from agriculture in the UK CEH, Edinburgh. Gijzen H. J. and Mulder A. (2001). The nitrogen cycle out of balance. Water21, August, International Water Association, London IFA (2012). IFADATA International Fertiliser Industry Association Data Base. ( Jasinski S M (2012). Phosphate Rock, Mineral Commodity Summaries. US Geological Survey. January. Mulder A. (2003). The quest for sustainable nitrogen removal technologies. Water Science and Technoogy, 48(1), National Audit Office (2010). Tackling diffuse water pollution in England. National Audit Office, London. Postage J. R. (1998). Nitrogen Fixation. Third Edition, Cambridge University Press, Cambridge. RFA Renewable Fuel Association (2008). Industry Statistics: Historic US Fuel Ethanol Production. URL: [07 May 2008]. Webb et al. (2006). Atmospheric Environment, 40,