End of life modeling

Question

I'm doing a cradle to grave LCA of widget-manufacturing. I've read the manual about EOL modeling, but it's based on a specific model that includes pre-built processes for the PET bottle. Would you be able to explain things in a more generic way?

I have inputs A,B and C to make my widget (Process: Widget). At EOL, the widget will be incinerated; I want to know what toxins are released. (Calculating the energy produced from incineration would be a bonus but is not my primary focus.)

For both Material Flow Logic and/or Opposite Direction Approach, what do I do now?

I'm using OpenLCA 1.10 and the Evah OzLCI2019 database. It has waste flows for some of my major inputs (A and C), but not smaller ones (such as specific adhesives and paints), as well as Waste Incineration flows. But my question is less about the specific database I'm using and more about the general concepts/steps I need to do for any waste analysis.

Thank you.

Answer 1

Ok, so you have a process "widget use" after your production, which then has "waste widget" as output? Then you need another process to treat the waste widget, which is a waste flow. The opposite direction approach is more historic.

To model the full life cycle, then, you can add a product flow "using the widget" to the process where you use the widget, this would be the quantitative reference for the product system.

Comments

I don't think I understand your explanation correctly.

Per above, I made a process "widget use" whose input is "widget" and output is "widget waste".

I'm having trouble making a separate process to treat the widget waste. If I make it a waste treatment process  then it doesn't show the flows I need (it just shows a few, from construction and metal). If I make it a product, then what is the input and what is the output?

Finally, you are saying to add the "widget use" flow to which process? "widget use" process?


This is hard to figure out since the Bottle example in the case study uses a pre-made waste process with lots of inputs and outputs; whereas I need to build my own waste process--I obviously know the inputs but I don't know the outputs.

---

HI Andreas,

Is there any way you could explain the solution in plain English so us novices with the same issue can learn how to do this?

Maybe showing the steps needed instead of an unhelpful answer that can only be understood by openLCA experts?

---

Ok I will try. If you want to model waste as output of your process, create a waste flow, set it as output of your process. If you have a process that has waste as input (in reality), model this in openLCA with a waste flow that is input into your process. Plain enough?

---

Is there any chance you could provide a screen shot of the inputs/outputs of what you mean?

I tried t decipher your directions but i am still returning all 0's in the results.