+1 vote
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Fundamental beginner question. Say I have a flow for a plastic pellet and I want to model it being formed through injection molding. I could create my own process called "injection molding" and run the plastic and electricity, etc into the process, but it would be a huge WAG on what goes into this process. Enter the "injection molding" process that is available in Ecoinvent 3.1.  This says that for every 0.994 kg of finished plastic you include 1kg of "injection molding." The way I read this is you create a process of your own called say "injection molding" then run the plastic granulate in as a flow as well as the "injection molding" flow that is an output from the injection molding process (effectively making the injection molding process from Ecoinvent a "provider.").   Is this how this is done, or would I actually attempt to add the plastic granulate as an input flow to the injection molding process? Seems to me these DB processes that already have hundreds of inputs and outputs would not benefit from me guessing at adding input/output flows and should only be used as "provider" processes, but that's just a guess. If there is a way to effectively add inputs/outputs to these complex DB processes I'd need to see an example of how to go about it (i.e. this was eluded to as "Part 2" of the PET bottle production video in 2014, but this video does not seem to exist on YouTube).  Crux of this, as a beginner, should I think of DB processes as simply "providers"?
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1 Answer

+1 vote
by (22.6k points)
Databases contain Life Cycle Inventory data (background system) and complement what you model yourself (foreground system). Usually, it is wise not to change processes of the background system but to create your own processes (or copies from background data sets which you can then change) and to use the processes from the database as providers to your own processes or vice versa. I hope this helps.
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