Wastewater LCI Initiative

How to model the impact of chemicals in wastewater? After use chemicals often end up in municipal wastewater treatment plants, where they are subject to degradation depending on their different nature. There are currently no substance-specific LCA models available to adequately model this particular issue but we have a club that aims to improve this.

The client

Crowdfunded project

Our role

2.-0 LCA consultants have started an initiative to model the substance-specific fate and effect of chemicals in wastewater. This initiative is open to everyone. By subscribing you become a partner and have access to a various tools including a model that calculates substance-specific life cycle inventories of chemicals going down the drain.

Substance-specific LCA model for chemicals sent down the drain

The problem

Very often the fate of chemicals after use is to be sent to municipal wastewater treatment plants (MWWTP), where they are subject to degradation. Current LCA models typically reflect the average conditions in MWWTPs, rather than the specific fate of particular chemicals. However different chemicals behave differently in MWWTPs, depending on their physical-chemical properties and biodegradability. An accurate modeling of the life cycle impacts of chemicals requires taking into account this specific behavior in a MWWTP, namely whether a chemical will be either degraded, volatilized, partitioned to sludge, discharged unchanged, or a combination of these.

There are currently no available LCA models to solve this particular problem.

The solution

2.-0 LCA consultants have started an initiative to model the impact of chemicals in wastewater. You can become partner of this initiative and have access to a model that calculates substance-specific life cycle inventories of chemicals sent down the drain, including:

  • The fate of the substance in the MWWTP and downstream in the environment.
  • Direct and indirect emissions from wastewater treatment, with and without nutrient removal.
  • Sludge disposal: landfilling, incineration, landfarming, and co-products from sludge disposal.
  • Greenhouse-gas emissions from degradation of the substance in the environment, in the case it is not degraded in the MWWTP.
  • Inventories in excel in an easy format for export to LCA software.
  • Ecoinvent-compliant inventories.

Why this is needed

We think this tool is needed for the following reasons:

  • For an accurate inventory accounting across the life cycle of chemicals, in particular of those used in consumer products (cleaning, personal care).
  • For a complete carbon footprinting of chemicals sent down the drain, taking into account not only the connection to MWWTPs, but also those cases where chemicals are directly discharged to the environment without treatment.
  • To accurately account for the fate of chemicals after the use stage, namely the fraction of discharged chemical reaching the natural environment via treated effluent, as well as through other routes like air or soil.

Deliverable and timeline

The wastewater initiative is open for everyone. Subscription costs 3.000 EUR, giving access to:

  • An excel-based calculation tool.
  • A report describing the model and how to use the tool, with some examples.
  • A helpdesk to solve your problems when you start using the tool.

The project ends with the publication of a peer-reviewed article published in a scientific journal. A short presentation article is available: The Wastewater life cycle inventory tool.

The expected duration of the project is 9 months. A beta version of the model would be released for partners to test in month 6. Feedback from the testing period would be incorporated in the final version of the model.

Some of our current members

  • Henkel
  • L’Oréal
  • Procter and Gamble
  • Umeå University, Green Technology and Environmental Economics Research Initiative
  • Unilever
  • University of Bordeaux

To go to the club click here.