Presentation on theme: "Dees Lijmbach, President Technical Committee,"— Presentation transcript:
1Phosphate removal and phosphate recovery: Towards Sustainable Development Dees Lijmbach, President Technical Committee,Chris Thornton, co-ordinator,CEEPCentre Européen d’Etudes des PolyphosphatesCOPPERAS - November 2000
8How did phosphorus recycling break down in Europe? The growth of cities (16th Century onwards)The introduction of sewage collection and treatment systemsDecline in agricultural re-use of sewage biosolids
9Modern society conducts phosphorus from the land and out to the rivers and sea
10Why re-visit phosphorus recycling now? Phosphate rock reserves and costsImpurities in phosphate rockIncreasingly, phosphate removal from waste water will be required by lawOpportunity to improve waste water treatment economics/ sludge cycleSewage and animal wastes are, potentially, a rich source of pure phosphate (45,000 and 200,000 tonnes of P per annum, respectively in UK)
11Why re-visit phosphorus recycling now? Agricultural spreading is the BEST way to recycle phosphorus (and nitrogen values, biosolids, …)But this option is declining across Europe : - concentration of cities / storage - transport problems - competition from animal manures - legislative and social pressure re contaminantsAlso, the P:N ratio in sewage sludge is higher than agronomic requirements
12Depletion of Phosphate Rock Reserves% Depletion20406080100High growthMedium growthLow growthConservation scenario
14Phosphoric acid analyses trace impurities Acid from Morocco phosphate rock ppmAlCdCrFeMgNaNiTiZnMnCu 23AsOrganic C 50Acid from Geestmerambacht recovered phosphates ppmAlCd <6CrFeMgNaNiTiZnMnCuAsOrganic C >2000
15Possible pathways for P-recovery - 1 Precipitation of a recyclable phosphate product from liquors in wwtp: - calcium phosphate -> P-industry - struvite (magnesium ammonium phosphate) -> fertiliser use - synergy with biological P-removal high-P side streams, P release in digesters, avoidance of struvite deposit problems) - other possible technologies may allow precipitation from wwtp main stream - ion exchangers, membranes ...
16Full scale phosphate recovery (as calcium phosphates) from sewage : DHV Crystalactor® at Geestmerambacht sewage works, near Edam, Holland (230,000 pe.)
18Full scale struvite recovery plant, Shimane Prefecture, Japan Full scale struvite recovery plant, Shimane Prefecture, Japan. Capacity : m2/day. Unitika Ltd / Japan Sewage Works Agency
19Phosphorus Recovery: Remaining technical/economic concerns Chemistry of P-recovery by CaP or struvite precipitation looks simple but is poorly understood.Inadequate knowledge of reaction kinetics.Existing reactor designs are far from optimised.Further LCA , economic & logistic evaluation is needed.
20Despite this:There are already about a dozen demonstration scale and full scale plants operating world-wide.Small amounts of recovered phosphate are already reaching industry.
21Possible pathways for P-recovery - 2 Recovery of phosphates in combination with existing chemical P-stripping - chemical constraints: - no known recycling pathway to date for iron phosphates - aluminium phosphates can be recycled in Thermphos’ Vlissingen furnaces, Holland - physical constraints : - how to recover a low-water, recyclable product and not a “sludge”, - need to separate phosphate product from sludge biosolids
22Possible pathways for P-recovery - 3 Recovery from sewage sludges or sludge incineration ashes - problems : - iron (from chemical P-stripping/flocculants used in sewage treatment) - copper (from diffuse sources : piping, diet ...)
23CEEP and P recovery Contacts with water companies and regulators The European detergent and technical phosphate industry is committed to “making it happen” and is leading research in the area.Contacts with water companies and regulatorsPromotion - communications : SCOPE Newsletter, P-recovery conference (Holland, 12th-14th March 2001)EU 5th Framework Proposal CYCLOPHOS addressing precipitation of calcium phosphate and struvitePossibilities for co-operation with INCOPA ?
24Cyclophos Industrial Partners Water Industry: - CIWEM - Berlin Wasser - Lyonnaise des Eaux - Thames, Anglian, Yorkshire, Severn Trent - Canal Isabel II - STOWA - Polish water industry - Posch and Partners - WS AtkinsNational regulators: - UK Environment Agency - Spanish Environment Ministry - Swedish Environmental Protection Agency
25Phosphorus Recovery: current CEEP research Scenarios for struvite recovery economics Imperial College, LondonFeasibility of P-recovery and recycling in Benelux STOWA/Thermphos/HaskoningEconomics and sludge management implications Office Internationale de l’EauSludge production implications INSA Toulouse, France
26Phosphorus Recovery: current CEEP research Precipitation reactor design parameters LAGEP/Uinversité Lyon II, FranceP-recovery potential in different areas of 3 bio-P wwtps CSIC Madrid/ Canal Isabel II Water CompanyStruvite formation in STW Imperial College (joint project with UK water industry).Testing of full-scale struvite precipitation reactor at Treviso bio-P sewage works, Italy (Ancona, Verona, Venice Universities)
27Phosphorus Recovery: current CEEP research Testing of a pilot scale struvite reactor at Zarbze sewage works, Poland, Lodz Technical University Bielsko BiélaCrystallisation of calcium phosphates using calcite seed Karlsruhe Research CentrePrecipitation of calcium phosphates - Centre for Ecology & Hydrology, UK and Natural history Museum, LondonRecovery of phosphates by reversible adsorption onto fly ash, Bath University, UK
28Phosphorus Recovery: current CEEP research Biologically induced P precipitation in combination with biological P-removal from sewage Queens University, Belfast.Application of REM-NUT ion exchange for P recovery from sewage works main stream Bari Polytechnic, ItalyPathways for P recovery from sewage sludges Swedish Royal Institute of TechnologyPhosphorus separation and recovery in animal manures Institute of Grassland & Environmental Research, UK.
29Recovery of P from iron compounds ? Results of an initial experiment using sulfate reducing bacteria to solubilise phosphates from iron phosphate sludge,Jan Suschka, Lodz Tech. Univ, Bielsko Biéla, Poland