0 votes
Good morning,

I have a doubt about a model I am working on. I am using the Ecoinvent 3.5 Database. In the model I have to insert as input "3´,5´-dimethoxy-4´-hydroxyacetophenone" used as chemical in a industrial process. I found this substance only in the elementary flow as "emission". Is it correct to insert it as input in the model? Thank you in advance.
in Miscellaneous by (120 points)

2 Answers

+1 vote
by (48.7k points)
Hi, you can of course insert it, but it will remain an elementary flow and as such cannot be exchanged from one process to another. If you need it as a product, you can simply create a new flow, as product.

Hth, Andreas

- and afterthought: Since the existing elementary flow is an emission, it does not make much sense to enter it as input, unless you have a process that aggregates a system exansion calculation for example.
0 votes
by (9.8k points)
In addition to the answer of Andreas: it is highly recommended to never put emissions of elementary flows on the input side or resource consumptions of elementary flows on the output side but to use negative values then. openLCA infers the impact direction of an elementary flow from where this flow occurs in the processes. When these sides are mixed for a flow it can lead to strange results regarding the impact assessment (because openLCA then does not know if the characterization factor should be negative for the input or output side).