New technologies to recycle phosphor

1. New technologies to recycle phosphor Sven Gjedde Sommer University of Southern Denmark Faculty of Engineering Inst. of Chemical Eng., Biotechnology and Environmental Technology

2. Problems and opportunities

3. Cordell et al. 2009; The story of phosphorus: Global food security and food for thought

4. Which technology ensure that livestock manure P is not lost or wasted? • The untreated manure is applied to field – fulfilling the crop need for plant nutrients. Focus may be on P, N and K.

5. Regional and local high production of cattle and pigs • Manure must be transported from farms with too much plant nutrients to farms having a need with TANKERS or by pumping. • Manure is separated, processesed, transported • Biogas treated • Incinerated • Ash, charcoal, Pelleted with additives • P refining

6. Struvite formation and sedimentation in a thickener Mg2++NH4++PO43-+6H2O⇌MgNH4PO4, 6H2O(s)

7. Screen or filterbed separation without additives

8. Using additives, koagulants iron and aluminium or/and polymers

9. Screw press separation

10. Decantering centrifuge

11. Separation cost The cost of an efficient separation of slurry using coagulants and flocculants and including the cost of screw press separation was estimated to be €1.8 per ton slurry Estevez et al. 2005

12. So what then? (Google translation of “HvadSå”?) • Farmers can spread the fibre fraction on land and incorporate it (Avoid ammonia emission) • The manure could be dried to produce a product that can be stored and transported: • Drum drying and pelleting • Torrefaction (Drying using the gas produced for heating) and pelleting

13. TorrefactionPyrolysis at low temperatures: 200-320oC Agri-Tech Producers Development needed to retain ammonium. Loss of about 20% of DM. Energy density of 18–20 GJ/m³ compared to 10–11 GJ/m³ Torrefiedfibres can be pelleted and stored without risk of more emission of GHG and ammonia. Torrefied biomass results in lower handling costs.

14. Use of pellets • The pellets may be considered a mineral fertilizer and applied to fields. • Alternatively the pellets may be incinerated and the ash can be used: • As a fertilizer • P can be recovered and used for P products

15. Ash as a fertilizer • P-availability of ash is reduced – by increasing temperature of the incineration or thermal gasification process. • A “maize fertilizer” have been developed by Kommunekemi. • Sulphuric and nitric acid added, the sludge dried and pelletized. • Acid addition increased P availability and N addition contributed to a fertilizer fulfilling plant nutrient needs of maize (corn) plants.

16. If slurry is separated without use of aluminium or iron additivesMaize or Corn FertilizerKommunekemi A/S Meat and bone ash Waste water sludge ash Fibre ash Anita Rye Ottosen Kommunekemi A/S

17. If slurry is separated with use of polymers, aluminium or iron additivesand cupper and zink has to be removed • Using polymer or iron or aluminium to improve P separation efficiency will also retain cupper and zink in the fibre fraction. These trace metal has to be removed. By dissolution – crystallisation processes • First acid is added to dissolve P which is removed. • Then pH is increased to dissolve Cu and Zn which is then removed. • There are many steps involved and the P recovery is very costly.

18. Production of pellets Water 2 % Hammermill ø8 mm screen Drying Animal house Solid manure Water 2 % Water 3,5 % Sieving Cooling Pelletising Conditioning Fines 5 % Water 2 % Steam Pellet storage 11.500 tons Additives 0 % 18 | Biomasse til el- og varmeproduktion | Karsten Thomsen, Kemi & Materialer | 19-11-2010 Introduction Keyfigures Proces Photo gallery Burning of pellets Summary Questions

19. Solid manure management scenariosGreenhouse emission from management of solid manureSide effects – energy and GHG emission NH3 N2O, N2, CH4 , CO2 NH3 CH4 CO2 NH3 N2O, N2, Excreta, straw VS, N, P Animal house, solid manure Solid manure 1) Composting 2) Reduced composting CROPS Field Water 1) Baseline 2) Baseline + compaction of stored solid manure NH3 N2O, N2, CH4 CO2 N2 CO2 Energy NH3 CH4 CO2 Solid manure storage Animal house, Solid manure Excreta VS, N, P Incineration Field CROPS Drying and pelleting P-Ash Biomass VS, Norg, TAN, P Biomass VS, Norg, TAN, P NH3 VFA 3) Incineration 4) Drying, pelleting and incineration

20. Greenhouse gas emission from the four scenarios, 6 ton litter from beef cattle production (one unit)

21. Side effect of the treatment NH3 Housing CO2 Stirring & pumping CO2 Pre-storage CO2 CO2 Stirring & pumping Separation CO2 CO2 Screw Press Transportation NH3 CO2 Pumping CH4 CH4 Storage (liquid) Storage (solid) CO2 CO2 Stirring & pumping N2O NH3 Loading CO2 Transportation Transportation CO2 Land application (liquid) Land application (solid) CO2 CO2 N2O Prevented mineral N fertilizer Prevented mineral N & P fertilizer NH3 NH3 N2O NO3- P P NO3- Marieke ten Hoeve – KU-Life

22. Conclusions • Application of untreated manure to crops near the animal house is very a resilient, sustainable and environmentally friendly technology • Simple separation can support efficient recycling (Definition see # 1) • Chains of treatment that include energy and “mineral fertilizer” production can be an attractive option for an industrial and specialised livestock production sector • Economy, regulations and incentives is the drivers.

23. http://content.alterra.wur.nl/Webdocs/PDFFiles/Alterrarapporten/AlterraRapport2158.pdfhttp://content.alterra.wur.nl/Webdocs/PDFFiles/Alterrarapporten/AlterraRapport2158.pdf