EoL (End of Life) and Recycling in LCA

Recycling is a special, complex, subject in LCA. This related with the fact that the LCA is to be made "from cradle to grave".
The issue is that recycling has to do with "from grave to cradle" (recycling closes the circle) , so a special set of rules has to be applied to resolve this problem in a practical way (Chapter 4 of the Thesis) .

The basic approach of the model of the EVR is, to stick to "from cradle to grave", and calculate the difference between the "base case" (without recycling) and the alternative "100% recycling case"
The "base case" is that the End of Life stage ends up in Land Fill and/or incineration.
The alternative is the "100% recycling case", see slide 6.2, where the End of Life stage ends with the storage of waste products (100% to be recycled) after seperation, and where 0% virgin material is applied.

The 'net eco-benefit of recycling' (=negative eco-costs) can than be calculated, being the "base case" minus the "100% recycling case":

'net eco-benefit of recycling' = {(a + b + c)+ f - (d + e) } x A

where:
a = eco-costs of materials depletion (including eco-costs of land), for 100% virgin material
b = eco-costs of energy ' from cradle to basic material', for 100 % virgin material
c = pol. prev. costs' from cradle to basic material', for100% virgin material
d = eco-costs of energy, including the stages of demolishing, separation, transport, storage and upgrading (to the basic material), at 100% recycled material
e = pol. prev. costs, including the stages of demolishing, separation, transport, storage and upgrading (to the basic material), at 100% recycled material
f = eco-costs of incineration and/or Land Fill.
A = percentage of recycled material
see tab LCA.

Note that the production stage and the use stage do not play a role in most of the situations, since the eco-costs of these stages are equal for the "base case" and the "100% recycling case". However, in some situations the use phase is influenced (e.g. when the product is less durable when recycled materials are applied, a multiplier must be applied for the difference in life time).

A complicating issue is the fact that recycling has often the character of cascading: the recycled materials are not applied in the same product, e.g. waste paper is recycled in boxes for transport packaging. The issue in literature is here which part of the eco-costs of the paper should be allocated to the box. This leads often to non-realistic and highly speculative allocation practices.
The best approach is the principle of "the primary user pays all the eco-burden". This means that the LCA for paper is kept separate from the LCA for the boxes. The last step op de LCA of paper is a stockpile of waste paper, and all the eco-burden until this last step is allocated to the paper. The LCA of the box starts with the stockpile of the waste paper. All eco-burden caused by transport and processing of the waste paper to make recycled paper of it, is allocated to the box.

Another complicating issue is the grade (=quality) of the recycled material: the grade is important for the value, not for the eco-costs. For example: when a special recycling operation results in a higher grade, the EVR of that operation is higher, not because of the effect in eco-costs, but because of the effect in value. For the same reason, re-use of components has a much better EVR than demolishing+recycling.
An amazing high percentage of the literature on recycling is blurring the issue allocation in cascades, and is blurring the issue of allocation in different grades, because value and eco-burden are not kept separate.

Literature: see under tab data, reference 1.0 and 1.4

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