Organomineral fertilisers (OMFs) were produced by coating biosolids granules with urea and potash. Two OMF formulations with N？:？P2O5？:？K2O compositions: 10？:？4？:？4 (OMF10) and 15？:？4？:？4 (OMF15) were developed for application in grassland and arable crops. Routine fertiliser analyses were conducted on four batches of OMF and biosolids granules and compared with a sample of urea to determine key physical and chemical properties of the materials which affect handling and spreading, soil behaviour, and fertiliser value. Bulk and particle densities were in the range of 608 to 618？kg？m？3, and 1297 to 1357？kg？m？3, respectively. Compression tests showed that OMF particles undergo deformation followed by multiple failures without disintegration of the granules when vertical load was applied. Static particle strength was between 1.18 and 4.33？N？mm？2 depending on the particle diameter. The use of a model for fertiliser particle distribution studies showed that OMF granules should be between 1.10 and 5.50？mm in diameter with about 80% of the particles in the range of 2.25 to 4.40？mm to enable application at 18？m tramline spacing. This research utilises novel technology to improve the fertiliser value of biosolids, reduce disposal costs, and deliver a range of environmental benefits associated with recycling. 1. Introduction 1.1. The Need for Recycling The production of sewage sludge (biosolids) in England and Wales is estimated to be 1.6 million tonnes (dry solids) per year [1] while this amount exceeds 10 million tonnes (dry solids) per year in the European Union (EU) [2]. Current levels of sludge production are set to increase due to the growth of the population and continuous adoption of improved technologies which are introduced to comply with standards required for the treatment of effluents. The quantity of sewage sludge recycled to agriculture varies considerably between EU member states. The UK and Ireland recycle approximately 70% and 90%, respectively, while Finland, Slovenia, Sweden, Holland, Greece, and Belgium recycle very low quantities or no sewage sludge to agriculture [3]. Conventional routes for disposal of sewage sludge include landfill and incineration which are considered to be unsustainable and therefore being progressively restricted. In this respect, the EU Landfill Directive 99/31/EC [4] requires reduction of 35% of biodegradable waste by 2020 of that generated in 1995 while the UK Government is committed to cut back CO2 emission by 20% [5] which narrows the opportunities for increased disposal through incineration. Expanding incineration
References
[1]
Department for Environment, Food, and Rural Affairs, Waste strategy for England 2007. PB12596, 2007, http://archive.defra.gov.uk/environment/waste/strategy/strategy07/documents/waste07-strategy.pdf.
[2]
F. Laturnus, K. von Arnold, and C. Gr？n, “Organic contaminants from sewage sludge applied to agricultural soils false alarm regarding possible problems for food safety?” Environmental Science and Pollution Research, vol. 14, no. 1, pp. 53–60, 2007.
[3]
S. R. Smith, The Implications For Human Health and Environment of Recycling of Biosolids Onto Agricultural Land, Centre for Environmental Control and Waste Management, Imperial College of London, London, UK, 2008.
[4]
Council of the European Communities, “Council Directive 99/31/EC of 26 April 1999 on the landfill of waste,” Official Journal of the European Communities L, vol. 182, pp. 1–19, 1999.
[5]
Department for Environment, Food and Rural Affairs, “Landfill Directive: What are the Landfill Directive’s aim and objectives?” 2007, http://archive.defra.gov.uk/environment/waste/strategy/legislation/landfill/documents/landfilldir.pdf.
[6]
D. L. Antille, Formulation, utilisation and evaluation of organomineral fertilisers [Engineering Doctorate Thesis], Cranfield University, Bedford, UK, 2011.
[7]
D. Edge, “Perspectives for nutrient removal from sewage and implications for sludge strategy,” Environmental Technology, vol. 20, no. 7, pp. 759–763, 1999.
[8]
Royal Society of London, “Reaping the benefits: science and the sustainable intensification of agriculture,” RS Policy Document 11/09, RS1608, London, UK, 2009, http://royalsociety.org/Reapingthebenefits/.
[9]
M. C. Paré, S. E. Allaire, L. Khiari, and C. Nduwamungu, “Physical properties of organo-mineral fertilizers—Short Communication,” Canadian Biosystems Engineering, vol. 51, no. 3, pp. 21–27, 2009.
[10]
C. J. Dawson and J. Hilton, “Fertiliser availability in a resource-limited world: production and recycling of nitrogen and phosphorus,” Food Policy, vol. 36, no. 1, pp. 14–22, 2011.
[11]
P. Heffer and M. Prud’homme, “Fertilizer outlook 2013–2017,” in Proceedings of the 81st International Fertilizer Industry Association Conference, p. 8, Chicago, Ill, USA, May 2013, Paper No.: A/13/78, http://www.fertilizer.org/.
[12]
J. R. Herring and R. J. Fantel, “Phosphate rock demand into the next century: impact on world food supply,” Nonrenewable Resources, vol. 2, no. 3, pp. 226–246, 1993.
[13]
H. P. Weikard and D. Seyhan, “Distribution of phosphorus resources between rich and poor countries: the effect of recycling,” Ecological Economics, vol. 68, no. 6, pp. 1749–1755, 2009.
[14]
S. E. Allaire and L. E. Parent, “Size guide number and rosin-rammler approaches to describe particle size distribution of granular organic-based fertilisers,” Biosystems Engineering, vol. 86, no. 4, pp. 503–509, 2003.
[15]
S. E. Allaire and L. E. Parent, “Physical properties of granular organic-based fertilisers, part 2: dynamic properties related to water,” Biosystems Engineering, vol. 87, no. 2, pp. 225–236, 2004.
[16]
S. E. Allaire and L. E. Parent, “Physical properties of granular organic-based fertilisers, part 1: static properties,” Biosystems Engineering, vol. 87, no. 1, pp. 79–87, 2004.
[17]
J. W. Hofstee and W. Huisman, “Handling and spreading of fertilizers. Part 1: physical properties of fertilizer in relation to particle motion,” Journal of Agricultural Engineering Research, vol. 47, pp. 213–234, 1990.
[18]
P. C. H. Miller, The measurement and classification of the flow and spreading characteristics of individual fertilisers, Proceeding no. 390, The International Fertiliser Society, York, UK, 1996.
[19]
J. W. Hofstee, Physical properties of fertilisers in relation to handling and spreading [Ph.D. Thesis], Department of Agricultural Engineering and Physics, Wageningen Agricultural University, Wageningen, The Netherlands, 1993.
[20]
K. Dilz and G. D. van Brakel, Effects of Uneven Fertiliser Spreading—Part I: A Literature Review, Proceeding no. 240, The International Fertiliser Society, York, UK, 1985.
[21]
Anon, “Minutes of Working Group 1—Overall structure of the future Fertiliser Regulations EC2003/2003,” Brussels, Belgium, Meeting on June 2012.
[22]
E. A. Makinde, “Effect of an organo-mineral fertilizer application on the growth and yield of maize,” Journal of Applied Sciences Research, vol. 3, no. 10, pp. 1152–1155, 2007.
[23]
World Intellectual Property Organization, (WO/2009/129589) Process for producing organo-mineral fertilizers, 2009, http://www.wipo.int/pctdb/en/wo.jsp?WO=2009129589.
[24]
M. C. Paré, S. E. Allaire, L. Khiari, and L. E. Parent, “Improving physical properties of organo-mineral fertilizers: Substitution of peat by pig slurry composts,” Applied Engineering in Agriculture, vol. 26, no. 3, pp. 447–454, 2010.
[25]
M. M. Rady, “A novel organo-mineral fertilizer can mitigate salinity stress effects for tomato production on reclaimed saline soil,” South African Journal of Botany, vol. 81, pp. 8–14, 2012.
[26]
B. J. Zebarth, R. Chabot, J. Coulombe, R. R. Simard, J. Douheret, and N. Tremblay, “Pelletized organo-mineral fertilizer product as a nitrogen source for potato production,” Canadian Journal of Soil Science, vol. 85, no. 3, pp. 387–395, 2005.
[27]
Food and Agricultural Organization of the United Nations, “Database on commercially available organic fertilizers and water-retaining products,” Land and Water Development Division, 2007, http://www.fao.org/AG/aGL/agll/orgfert/intro.stm.
[28]
M. Tejada, C. Benítez, and J. L. González, “Effects of application of two organomineral fertilizers on nutrient leaching losses and wheat crop,” Agronomy Journal, vol. 97, no. 3, pp. 960–967, 2005.
[29]
S. Spence, “Bestway Fertilisers,” Personal communication. Southern Water, Worthing, West Sussex, UK, 2010.
[30]
United Utilities Group PLC, US Patent No.: US7504035 B2, 17 March 2009 for the treatment of putrescible cakes. Assignee: United Utilities PLC. Inventors: M.S. Le (UK) and N.T. Shatin (Hong Kong), 2009.
[31]
D. L. Antille, R. Sakrabani, and R. J. Godwin, “Nitrogen and phosphorus availability following topsoil application of organomineral fertilisers,” American Society of Agricultural and Biological Engineers, vol. 5, pp. 4134–4150, 2012.
[32]
Council of European Communities, “Council Directive EU Sewage Sludge Directive 86/278/EEC of 12 June 1986 on the protection of the environment and the soil when sewage sludge is used in agriculture,” Official Journal of the European Communities L, vol. 181, p. 6, 1986.
[33]
ADAS, Guidelines for the Application of Sewage Sludge to Agricultural Land: the Safe Sludge Matrix, ADAS Gleadthorpe Research Centre, Mansfield, UK, 3rd edition, 2001.
[34]
M. S. Le, T. Briddon, D. Harrison, and A. Werker, “Enzymic hydrolysis technology demonstration: production of enhanced treated biosolids for agricultural recycling,” in Proceedings of the 11th European Biosolids and Organic Resources Conference. Aqua-Enviro Technology Transfer, Wakefield, UK, November 2006.
[35]
Department for Environment, Food and Rural Affairs, Fertiliser Manual (RB209), The Stationery Office, London, UK, 8th edition, 2010.
[36]
R. J. Skinner and A. D. Todd, “Twenty-five years of monitoring pH and nutrient status of soils in England and Wales,” Soil Use and Management, vol. 14, no. 3, pp. 162–169, 1998.
[37]
United Utilities Group PLC, “Chemical analyses of sewage sludge (biosolids),” Internal Report, United Utilities Group PLC, Warrington, UK, 2006.
[38]
M. Alvarez-Cobelas, S. Sánchez-Carrilo, D. G. Angeler, and R. Sánchez-Andrés, “Phosphorus exports from catchments: a global view,” Journal of the North American Benthological Society, vol. 28, no. 4, pp. 805–820, 2009.
[39]
C. J. Dawson, “Phosphate and potash—reconsidering their importance and use,” Journal of the Royal Agricultural Society of England, vol. 172, pp. 1–9, 2011.
[40]
AFCOME, Association Fran？aise de Commercialisation et de Mélange d’Engrais, “Bulk blending manuel de qualité, 1ére partie,” in Proceedings of the 14th International Meeting of the Association Fran？aise de Commercialisation et de Mélange d’Engrais (L’AFCOME ’95), 1995, http://www.afcome.org/Accueil.html.
[41]
L. E. Sommers, “Chemical composition of sewage sludges and analysis of their potential use as fertilizers,” Journal of Environmental Quality, vol. 6, no. 2, pp. 225–232, 1977.
[42]
J. B. A. Dumas, “Procédés de l'analyse organique,” Annales des Chimie et des Physique, vol. 2, no. 47, pp. 198–213, 1831.
[43]
Ministry of Agriculture, Fisheries and Food, The Analysis of Agricultural Materials (RB 427), The Stationery Office, London, UK, 3rd edition, 1986.
[44]
British Standard 7755 Section 3.13, Soil Quality. Chemical Methods. Determination of Cadmium, Chromium, Cobalt, Copper, Lead, Manganese, Nickel and Zinc in Aqua Regia Extracts of Soil. Flame and Electrothermal Atomic Absorption Spectrometric Methods, The British Standards Institution, London, UK, 1998, Equivalent to ISO, 11047:1998.
[45]
K. C. Jones and A. E. Johnston, “Cadmium in cereal grain and herbage from long-term experimental plots at Rothamsted, UK,” Environmental Pollution, vol. 57, no. 3, pp. 199–216, 1989.
[46]
Ministry of Agriculture, Fisheries, and Food, Code of Good Agricultural Practice For the Protection of Soil (Revised), The Stationery Office, London, UK, 1998.
[47]
British Standard, Solid Fertilizers—Test Sieving [British-Adopted European Standard], The British Standards Institution, London, UK, 1995.
[48]
K. Persson, Interaction between fertilisers and spreaders, Proceeding no. 389, The International Fertiliser Society, York, UK, 1996.
[49]
O. Miserque, E. Pirard, Y. Schenkel, O. Mostade, and B. Huyghebaert, “Spreading segregation of blended fertilizers: influence of the particles properties,” Applied Engineering in Agriculture, vol. 24, no. 2, pp. 137–144, 2008.
[50]
I. A. Bridle, M. S. A. Bradley, A. R. Reed et al., Non-segregating blended fertiliser development: a new predictive test for optimising granulometry, Proceeding no. 547, The International Fertiliser Society, York, UK, 2004.
[51]
Canadian Fertilizer Institute, Bulk Blend. Quality Control Manual, CFI, Ontario, Canada, 2001.
[52]
British Standard, “Fertilizers—determination of bulk density (loose) [British-adopted European Standard equivalent to the modified version of ISO, 3944 (1992)],” The British Standards Institution, London, UK, 1995.
G. J. Gouw and H. W. Wevers, “Behaviour of an INSTRON 1122 under cyclic testing over a small displacement range,” Journal of Biomedical Engineering, vol. 4, no. 1, pp. 72–74, 1982.
[55]
American Society of Agricultural Engineers, Method of Determining and Expressing Fineness of Feed Materials by Sieving, ASAE, St. Joseph, Mich, USA, 2006, ANSI/ASAE-S.319.3 FEB03. ASAE Standards.
F. J. Rohlf and R. R. Sokal, Statistical Tables, W. H. Freeman, New York, NY, USA, 3rd edition, 1995.
[58]
M. I. Kokkora, D. L. Antille, and S. F. Tyrrel, “Considerations for recycling of compost and biosolids in agricultural soil,” in Soil Engineering, A. P. Dedousis and T. Bartzanas, Eds., vol. 20 of Soil Biology Series, chapter 13, pp. 195–215, Springer, Berlin, Germany, 2010.
[59]
O. Miserque and E. Pirard, “Segregation of the bulk blend fertilizers,” Chemometrics and Intelligent Laboratory Systems, vol. 74, no. 1, pp. 215–224, 2004.
[60]
M. S. A. Bradley and R. J. Farnish, Segregation of blended fertilisers during spreading: the effect of differences in ballistic properties, Proceeding no. 554, The International Fertiliser Society, York, UK, 2005.
[61]
K. F. K？mpfe, H. J. J？schke, and W. Brinschwitz, “Zusammenhang zwischen wesentlichen physikalischen eigenschaften und der verteilgenauigkeit der mineraldünger bei der application,” Agrartechnik, vol. 32, no. 6, pp. 253–256, 1982.
[62]
T. P. Hignett, “Physical and chemical properties of fertilizers and methods for their determination,” in Fertilizer Manual, T. P. Hignett, Ed., vol. 15 of Developments in Plant and Soil Sciences Series, chapter 22, pp. 284–316, 1985.
[63]
UNIDO/IFDC, Fertilizer Manual. International Fertilizer Development Centre, United Nations Industrial Development Organization, Kluwer Academic Publication, Muscle Shoals, Ala, USA, 1998.
[64]
F. T. Nielsson, “Granulation,” in Manual of Fertilizer Processing, F. T. Nielsson, Ed., vol. 5 of Fertilizer Science and Technology Series, chapter 9, pp. 159–201, Marcel Dekker, New York, NY, USA, 1987.
[65]
A. Aphale, N. Bolander, J. Park, L. Shaw, J. Svec, and C. Wassgren, “Granular fertiliser particle dynamics on and off a spinner spreader,” Biosystems Engineering, vol. 85, no. 3, pp. 319–329, 2003.
[66]
S. Parkin, B. Basford, and P. C. H. Miller, “Spreading accuracy of solid urea fertilisers,” DEFRA Report NT2610, 2005, Component Report for DEFRA Project NT26, http://randd.defra.gov.uk/Document.aspx?Document=nt2610_6823_FRP.pdf.
[67]
D. L. Antille, L. Gallar-Redondo, and R. J. Godwin, “Determining the particle size range of organomineral fertilisers based on the spreading characteristics of the material,” American Society of Agricultural and Biological Engineers, vol. 5, pp. 4251–4268, 2013.
[68]
American Society of Agricultural Engineers, Procedure For Measuring Distribution Uniformity and Calibrating Granular Broadcast Spreaders, ASAE, St. Joseph, Mich, USA, 46th edition, 1999, ASAE-S. 341.2. ASAE Standards 1999.
