Circular P - wastewater treatment for phosphorus recycling | 2 Mers Seas Zeeën

Circular P

Circular P - wastewater treatment for phosphorus recycling

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Circular economy


Phosphorus (P) is a critical raw material, essential for food production (as a fertilizer). There are no primary Phosphorus resources in the EU and future high cost or restricted availability due to unforeseen events may affect food security. Phosphorus is used very inefficiently, with over 80% going to waste. A large proportion of P is lost to natural water bodies in sewage effluent (over 60%), where it causes eutrophication (leading to algal blooms, low oxygen conditions, and damage to wildlife and ecosystem processes). Recovery of P from sewage sludge to use as fertilizer could have a significant benefit in reducing P imports and improving water quality. However, low P import prices, fragmented regulation (e.g. ban on using sewage sludge on farmland in some countries), and concerns regarding pollutants in sewage sludge are significant barriers to the development of a circular economy in P. This project aims to focus on the process and cost efficiency of P recovery from the wastewater treatment process, which has two main steps: removal of P from wastewater and recovery of the P in a form that is bioavailable and economically transportable. An integrated, process optimization approach will lead to identification of beneficial process combinations, such as C-Tech (a highly efficient P removal process) and various conversion technologies for recovery of P-rich biosolids as fertilizer. Technical, regulatory, and economic barriers and opportunities will be addressed.

Creation date: 31/08/2018

Bloc onglets

Bloc 1

Overall objective

To improve the efficiency of phosphorus use by increasing its recovery from municipal wastewater and subsequent use as agricultural fertilizer. This is an important stage in the circular economy of P, which is a critical raw material (designated by EU in 2014) that is used very inefficiently. An important secondary objective is to reduce the discharge of P to lakes and rivers and the sea, which is the major cause of eutrophication and thus of water framework directive good ecological status failures.

Bloc 2


The project will demonstrate and test combinations of wastewater treatment with P recovery/fertilizer production processes to maximise efficiency of P recycling and to optimize cost/benefit of the combined process. To date, efforts have focused on commercialization of the recovery of P from sewage sludge in a form that is available as a fertilizer. Little if any attention has been paid to the quality of the sewage sludge as a feedstock for that process. Higher P concentrations in the sewage sludge will improve the economics of the process. However, it is not enough to focus on one aspect of the process alone. An integrated perspective is required to demonstrate the cost effectiveness of a circular approach to managing P in wastewater treatment. Rather than focus on just one stage of the cycle, the project will recognize that there are four interrelated aspects of the business model: fertilizer production from recovered P as a commercial product (fertilizer); costs of sewage sludge production and disposal; environmental benefits (which can be monetized); energy costs – energy is used in the process and produced by it (where sludge is incinerated). This approach will drive different investment decisions for upgrading wastewater treatment works which favour the circular economy of P. Through the experience of implementing commercial scale tests, real barriers and opportunities will be identified regarding technology, regulation and markets. These barriers may include: • Knowledge and access to information on technologies available, and their complementarities in the context of P circular economy • Conflicting priorities between wastewater treatment objectives and P recycling objectives • First-cost versus lifetime cost decision-making • Regulatory and other market barriers.

Bloc 3

Expected result

Through better integration of P recovery into wastewater treatment plant design and operation (to optimize the economics of combined wastewater treatment and P recovery as fertilizer): 1. more P is recycled 2. water quality in natural water bodies is improved.

Bloc 4

Cross-border added-value

• Develop a replicable and transferable model for P recycling in the water industry, learning from best practice within the 2Seas region • Testing of process and costs in a range of regulatory and economic environments to provide more transferable results, having greater impact. • Some countries are more advanced in P recovery – the leader-follower approach can benefit transferability of experience • Review and analyse experience on approaches to water and agricultural regulation to understand what are the most effective drivers for P circular economy, which spans water, agriculture, food sectors. Types of partner sought: • Waste water treatment companies/authorities • Water and Pollution regulators • Companies producing technologies to manage P • Research institutions • Networks/Associations in water and agriculture sectors