P-Recovery from Wastewater – A Beneficial Strategy for Utilities? 2018 Danube Water Conference May 2 – 3, 2018 Arabel Amann

Wastewater Treatment First and foremost tasks: protection of the aquatic environment (reduction standard parameters COD, P, N, ...) safe disposal of sewage sludge Recent years - discussions on multiple additional functions/goals: improvement of treatment for micropollutants, antibiotic resistance, microplastics,… resource efficiency: reduction energy demand, improved heat reuse resource recovery: conversion biomass to energy, nitrogen, phosphorus, …

Phosphorus – A critical raw material white phosphorus (P4) since 2017 Supply Risk phosphate rock since 2014 Source: European Commission (2017) Economic Importance

Phosphorus losses in the EU 27 Source: van Dijk. et al. (2016)

Recovery points and potentials sludge liquor sewage sludge sewage sludge ash Source: modified from Montag, D. (2008)

Costs Comparison of Technologies Reference: Conventional WWTP with enhanced P removal and co-incineration of sludge Result: Beneficial recovery possible, high uncertainties 10 % are for monoincineration Source: Egle et al. (2016) Reference system has decisive impacts on cost evaluation!!!

Factors influencing costs and benefits P-removal type (biological, chemical, filter,…) Sludge stabilisation (aerobic, anaerobic,…) Sludge dewatering efficiency Current sewage sludge transport distances Sewage sludge disposal costs Product quality and market price (for P and other secondary products) System boundaries!

Example System I WWTP with enhanced biological P removal (EBPR) and sludge digester

Struvite from Sludge Supernatant Precipitation of struvite (NH4MgPO4·6H2O) with pH-adjustment and Mg dosing Operational and Financial Benefits: Reduction of pipe clogging Reduction of nutrient backflow to WWTP-influent + Revenue for product Example: Ostara WASSTRIP® and PEARL® Source Picture: OSTARA (2017)

Struvite after Sludge Digester Precipitation of struvite (NH4MgPO4·6H2O) with pH-adjustment and Mg dosing Operational and Financial Benefits: Reduction of pipe clogging Reduction of nutrient backflow to WWTP-influent Improvement of sludge dewatering Reduction of polymer demand + Revenue for product Example: AirPrex® Source Picture: CNP (2015)

Struvite Processes around the world Véolia Struvia® Helsingor (DK): 70.000 EW Suez Phosphogreen® Aarhus (DK): 84.000 EW Marselisborg (DK): 200.000 EW AirPrex® Berlin (DE): 1 Million EW Amsterdam (NL) Ostara Pearl® Chicago (USA): 4,5 Millionen EW Slough (UK): 165.000 EW © Christian Kabbe 2017 https://de.batchgeo.com/map/0f9d56a3aa57a51379a3cb23af27d202 YES! (with Bio-P and Digestion) Limited! Business Case? Recovery?

Example System II Wastewater treatment with sewage sludge mono-incineration and disposal of ash

Example: P-acid production from ash Leaching of phosphorus from ash + cleaning of resulting acid-solution -> H3PO4 Financial Benefits: Reduction of ash for disposal (who exploits cost reduction?) + Revenue for product +/- Revenue for additional products (valorisation uncertain) Example: Remondis TetraPhos® Source Picture: Remondis

Example: Fertilizer production from ash Conversion of phosphorus in ash to plant available form by mixing with acids + granulation of product (only high quality ashes = low heavy metal content) Financial Benefits: No ash for disposal + Revenue for fertilizer Example: Seraplant® or Conventional Fertilizer Industry (ICL Fertilizer) Source Pictures: Klärschlamm-Kooperation M-V (2017)

Ash Processes Pilot Plants in Europe Fertilizer Production ICL Fertiliser: Amsterdam, full-scale/ Ludwigshafen, planned Ash2Phos® (Helsingborg, pilot) P-acid Production EcoPhos® (Varna, Demo/Dürnkirchen), TetraPhos® (Hamburg, full-scale planned) PARFORCE® (Freiberg DE, Demo) Phos4Life (Spain/Zurich, laboratory scale) P4 Production ICL Fertilizers – RecoPhos InduCarb (Patent acquired) © Christian Kabbe 2017 https://de.batchgeo.com/map/0f9d56a3aa57a51379a3cb23af27d202 POSSIBLE (uncertainties) High! Business Case? Recovery?

System Perspective Example – Canton of Zurich, Switzerland Disposal cost in canton in 2014 before operation of mono-incineration Calculated costs with mono-incineration and phosphor recovery from ash Source Picture: modified from Adam (2017) Digestion Dewatering Transport Thermal Treatment Phosphor Mining

Summary (I) P recovery is no core task of wastewater utilities (yet) P-recovery = beneficial for utilities? Yes, under specific circumstances… General reference point = treatment costs + sewage sludge disposal price 2 examples were benefits can be exploited: WWTP with enhanced biological P-removal WWTP with high disposal costs for sewage sludge

Summary (II) Under different WWTP and disposal schemes tendency to a cost increase, e.g. chemical P-removal agricultural application or co-incineration of sludge (low disposal costs) no mono-incineration plants (investment needed) Still, other benefits could arise e.g. higher independency from disposal market (municipal incineration) P-recovery an integral part of sewage sludge disposal concepts

THANK YOU! Management Perspective Egle, L., Zoboli, O., Thaler, S., Rechberger, H., Zessner, M. (2014) The Austrian P budget as a basis for resource optimization. Resources, Conservation and Recycling 83, 152–162. https://doi.org/10.1016/j.resconrec.2013.09.009 Zoboli, O., Laner, D., Zessner, M., Rechberger, H. (2016) Added Values of Time Series in Material Flow Analysis: The Austrian Phosphorus Budget from 1990 to 2011. Journal of Industrial Ecology 20, 1334–1348. https://doi.org/10.1111/jiec.12381 Zoboli, O., Zessner, M., Rechberger, H. (2016) Supporting phosphorus management in Austria: Potential, priorities and limitations. Science of The Total Environment 565, 313–323. https://doi.org/10.1016/j.scitotenv.2016.04.171 Technology Perspective Egle, L., Rechberger, H., Zessner, M. (2015) Overview and description of technologies for recovering phosphorus from municipal wastewater. Resources, Conservation and Recycling 105, 325–346. https://doi.org/10.1016/j.resconrec.2015.09.016 Egle, L., Rechberger, H., Krampe, J., Zessner, M. (2016) Phosphorus recovery from municipal wastewater: An integrated comparative technological, environmental and economic assessment of P recovery technologies. Science of The Total Environment 571, 522–542. https://doi.org/10.1016/j.scitotenv.2016.07.019 Amann, A., Zoboli, O., Krampe, J., Rechberger, H., Zessner, M., Egle, L. (2018) Environmental impacts of phosphorus recovery from municipal wastewater. Resources, Conservation and Recycling 130, 127–139. https://doi.org/10.1016/j.resconrec.2017.11.002

Sources Adam (2017). Ziel und Strategie bei der Klärschlammverwertung und Phosphorrückgewinnung im Kanton Zürich. 22. Dreiländertreffen, Schweiz. CNP (2015). AirPrex™: Biosolids Treatment Optimization Process with the option of Phosphate Recovery. MWEA - Annual Biosolids Conference, March 2nd 2015. European Commission (2017). Communication on the list of critical raw materials 2017. Egle, L., Rechberger, H., Krampe, J., Zessner, M. (2016) Phosphorus recovery from municipal wastewater: An integrated comparative technological, environmental and economic assessment of P recovery technologies. Science of The Total Environment 571, 522–542. https://doi.org/10.1016/j.scitotenv.2016.07.019 Klärschlamm-Kooperation M-V (2017). Die Klärschlamm-Kooperation Mecklenburg-Vorpommern. Aktueller Stand 03.2017. OSTARA (2017). Ostara Process Flow Diagram Handout. Remondis (2018). TetraPhos Process Scheme Handout. van Dijk, K.C., Lesschen, J.P., Oenema, O., 2016. Phosphorus flows and balances of the European Union Member States. Science of The Total Environment, Special Issue on Sustainable Phosphorus Taking stock: Phosphorus supply from natural and anthropogenic pools in the 21st Century 542, 1078–1093. https://doi.org/10.1016/j.scitotenv.2015.08.048