waste incineration

Question

Hello,

i`m writing my thesis about the comparison of a waste incineration of plastics and the recycling of plastics. My question is about the incineration. First the product is beeing transported in a process, after that it should be incinerated. the reference flow should be the `waste incineration of plastics (pe, pp, ps, pb)` with 1kg. Now my question: do i have to make this input negative, because it`s a negative output of the process `Waste incineration of plastics (PE, PP, PS, PB), at plant, average European waste-to-energy plant, without collection, transport and pre-treatment`?
Please help me, i would be very thankfull.

Best regards,
Jule

Answer 1

Hi Jule,
welcome. Well this seems like a classic "ecoinvent waste modeling" question which we think we can overcome with the new 1.7 version of openLCA, but for now:
- you have a process where waste is created (p), which is transported, and incincerated (i)
- p: waste on the input side, negative, also transport effort on the input side, positive (in tkm); i: waste on the output side, negative
You see that this is a double-complication: waste treatment needs so far be modeled like a product, so as output of a treatment process, and as consequence as input of a process where waste is created; to "save" the mass balances, the sign is reversed for both.
Hope this helps!
Andreas