Hello Aleksandra,
The approach to recycling depends on the system modelling you are doing. The most popular are:
Cut-off approach: The cut-off approach removes any impacts from the product's previous lifetime. This means that a recycled product will read 0 on all impact categories. No avoided emissions.
Consequential approach: The product is modelled as a part of the "previous" life cycle. It has all the impacts that come with it. However, since you "saved" it from being waste, you avoided the waste treatment process, which you can write as an avoided impact.
The approach to recycled content varies depending on a lot of factors, and it can have a great impact on the final result. It is most important to be consistent across the whole assessment, and transparent in your methodological choices. If you do not know how to ensure that, i would encourage you to read through some of the literature on the topic. I also know that EcoInvent has uploaded some tutorial videos on the topic.
Good luck, this is a tough area.
