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Hey guys, I'm having trouble understanding how to compare the individual unit processes WITHIN a product system. My assignment is to compare the various stages/unit process of biodiesel production, including soybean production, crude soybean oil extraction, and thirdly, biodiesel production from crrde soybean oil. But I'm not sure what to set my functional unit as, and how that relates to the quantitative reference. All the case studies and examples I've seen compare two separate product systems, but this appears to be a comparison within a single linked product system. Any thoughts?

Hm, what's the point in doing this comparison, can you explain?
Thank you!
Andreas

The assignment states that I need to perform a life cycle impact assessment of each of the 3 unit processes and to compare then. The assignment states that I need to come up with a functional unit to scale all 3 unit process data (the 3 aforementioned ones) and to keep in mind that the final output of the biodiesel process is 3.52 E5 g biodiesel.

Does this mean I make a product system for each of the unit processes and then compare the product systems within a project?

Yes :)

Okay, easy enough, thank you! So, as for the reference unit, do I input a reference unit as an output and use it as the "quantitative reference" within a process? Essentially, will all the different processes use the same quantitative reference? If not, how do I apply the chosen functional unit across all these processes?

This is probably a learning element in your assignment, the functional unit must be the same, but not necessarily the quantitative reference amount - you can set the latter when specifying the compared product systems in a project.