Avoided emissions of organic waste sent to Landfills

Question

Hello everyone,

I am conducting a comparative LCA analysis where I am comparing the GWP of producing urea vs. treating sewage sludge to be applied on the land as fertilizers. The treatment of sewage sludge reuses organic matter that is diverted from the landfill thus avoiding the GHG emissions of this practice. I would like to include these avoided emissions in my OpenLCA modeling. Has anyone ever modeled a similar scenario? If so, what is the best way to model such a scenario? Should I create the avoided process of landfilling organic matter OR use a "waste flow" when calling for the use of organic matter in my inputs? At present, I am using the waste flow " biowaste" from ecoinvent 3.6 databases.

Any input would be highly appreciated.

Thank you.

Answer 1

Hi Elissa,

there are several ways; the easiest and probably not terribly elegant way is to create an own process with "process-specific burdens", check the "process-specific burdens, xyz" in ecoinvent.

Or, you could model a system expansion / avoided process with the supply chain of the landfill, with the CO2 emissions.

Best wishes,

Andreas