Removing pharmaceutical residues from wastewater with sustainably-produced activated carbon

What do good water quality for people and the environment, prunings, pharmaceutical residues in wastewater and local circular solutions have in common? They all come together in the ‘Activate your Biomass’ concept. A consortium of pioneers has developed this concept and is now conducting an extensive study to determine its technical-economic feasibility in practice.

Pharmaceutical residues in wastewater

Over the last few decades large investments have been made in the further improvement of wastewater treatment – and with success. The quality of the wastewater treatment effluent has radically improved in many regards. There are however still substances whose removal rate is not sufficient. This concerns relatively low concentrations of a range of compounds including pharmaceutical residues. Even though the concentrations are low, their discharge is not desirable, something which is also pointed to in the European Water Framework Directive. A familiar way of removing pharmaceutical residues from wastewater is the dosing of powdered activated carbon in the activated sludge process during wastewater treatment; in the Netherlands this is also referred to as the ‘PACAS’ process. The used powdered carbon is then treated together with the biological sludge for processing and incineration. Following various successful pilot studies, the process will this year for the first time be introduced on an operational scale at the wastewater treatment plant in Leiden. A possible objection from the perspective of sustainability, is that a large portion of the standard types of powdered carbon are produced from fossil raw materials, such as turf, lignite or coal.

Activated carbon from local timber and prunings, ‘Activate your Biomass’

The P4S organisation in Almere has far-reaching plans to produce pellets from timber and prunings, which are locally available in great quantities. The idea is to then use them as a raw material for the production of activated carbon. It is expected that this path will lead to the production of quality powdered carbon that is suitable for the removal of pharmaceutical residues in wastewater treatment. This would offer a partial response to the above-mentioned objection regarding the sustainability of many standard types of powdered carbon.

The importance of water quality

‘Activate your biomass’ is looking not only at pharmaceutical residues, but also at pesticide residues, PFAS and many other compounds. Together, these are referred to as ‘emerging substances’. The discharge of these substances – even in relatively low concentrations – can be hazardous for the ecosystem, and is problematic for the drinking water provision. After all, about 40% of the drinking water in the Netherlands is produced from sources consisting entirely or in part of surface water. The current policy is generally directed at tackling pollution as much as possible at the source. In this context, the use of activated powdered carbon, produced from locally available timber and prunings, offers a powerful method for an at-source approach, as well as in the wastewater treatment. Naturally, the ‘Activate your Biomass’ concept still requires further investigation before it can be implemented in practice. The current technical-economic feasibility study will further clarify the matter. The results are expected soon after the summer this year.

About the initiators

The initiators have joined together to form a consortium consisting of the following parties, in alphabetical order:

• Allied Waters (www.alliedwaters.com): specialist in circular solutions with and for the water sector.
• AquaMinerals (www.aquaminerals.com): specialist in the upcycling of the residual streams of its participants in the water sector (collaborates with the ‘Energie- en Grondstoffenfabriek’).
• P4S (www.p4salmere.nl): organisation for the upcycling of bio-based raw materials, specifically, timber and prunings.
• Zuiderzeeland (www.zuiderzeeland.nl) Water Authority: responsible for water management and wastewater treatment in the Province of Flevoland.

Interested?

If you would like to learn more about our initiative, please contact us via secretariataw@alliedwaters.com, or directly contact one of the other consortium members. Please also feel free to contact us if you yourself, as a drinking water utility or Water Authority, have timber and prunings available.