Page 60 - Implementation of ITU-T international standards for sustainable management of waste electrical and electronic equipment: The path to a circular economy in Costa Rica

Implementation of ITU-T international standards for sustainable management of waste
electrical and electronic equipment: The path to a circular economy in Costa Rica

– PCs: information is reported as number of households with computers, so a minimum of
one computer per household was assumed to estimate the inventory.

EEE or WEEE flows are established between processes at the national level (e.g., from wholesale
importers to consumers); or between these internal processes and international trade relations
(e.g., international traders and importers). EEE flows are different for new and used products.
Each flow has a unique alphanumeric code as described in Figure 32. For example, 1-2N refers
to the flow for new items that come from process P1 and go to process P2.

Import flows of new and used EEE, in units and tonnes, were taken directly from the official
reports of the Directorate General of Customs for 2020. The types of importers reported were
grouped for this study into Trading Companies, State Institutions, Households, and Others, as
described in Figure 18 - Classification of natural and legal persons in public and private sectors
and their relationship with material flows.

A limiting factor was the lack of primary Figure 32 - Identification code
information (gathered from sources such as description of material flows in the
databases or surveys) or the little secondary diagrams
information available (gathered from other
sources such as reports or other projects
results) from the following actor’s groups:
non-importing retail distributors, private
sector (such as consumers), public sector,
households and “Other”.
This is reflected in the number of unknown or not analysed flows identified in red in the baseline
system in Figure 31.

The amount of EEE for own consumption imported by the Private Sector was not analysed due
to information shortcomings. This leads to a potential underestimation of final consumption
calculated for trading companies (Private Sector), and consequently, an overestimation of EEE
quantities consumed by the remaining sectors. This means that the values of EEE consumed
by the other sectors may be higher than their actual values.

3.6.1.1 Modelling considerations

Modelling took the following considerations into account:

– The change in the inventory of each process results from the balance between inputs and
outputs for 2020, according to the principle of matter conservation, i.e., the amount of
material before and after their use is the same.
– EEE flows from Importing Trading Companies to retail distributors and consumers are
differentiated in “New” and “Used”. These flows are estimated using sales distribution
(percentage of sales by type of customers) reported by importing companies in the study
surveys (Figure 33 and Figure 34).

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