2646 * Market-mix medium voltage category accounts for the emissions throughout the entire value chain of electricity, from generation, transmission, distribution, up until actual usage. 3. METHODOLOGY An LCA quantifies environmental impacts by following four stages outlined in the ISO 14040 and ISO 14044 frameworks: (1) goal and scope definition; (2) life cycle inventory (LCI); (3) life cycle impact assessment (LCIA); and (4) interpretation of the results. 3.1 Stage 1: Goal and scope definition The goal of this LCA study is to assess the global warming impact (CO2e emissions), of the main products produced by three mineral processing flow sheets. The results of the study provide insight into the potential impact of mineral processing equipment and identify the most significant factors. The scope of the study is described under the product system, functional unit, system boundaries, and data source(s). For this study, the product system includes the production of a mineral concentrate through mineral processing, with the functional unit being 1 tonne of produced concentrate for each commodity (copper, iron ore, lithium). A “gate-to-gate” system boundary is adopted, starting at comminution and ending at concentrate production, with auxiliary transfer equipment excluded due to data limitations. Ecoinvent was selected as the primary database for EFs. Global warming potential (GWP100) was the only impact category evaluated, reported as kg CO2e per functional unit, consistent with IPCC characterisation factors. 3.2 Stage 2: Life cycle inventory (LCI) The LCI involves compiling an inventory of all flows into and out of the product system, including energy streams, wear materials, raw materials/consumables, and output streams. Water as a raw material has been excluded from this analysis due to data/information limitations. Ideally, site-specific data (primary data) must be obtained. If not available, secondary data, i.e., generic data from literature or databases, will suffice [12]. Data was collected around the following parameters: flowsheets (entailing all plant units and their relevant streams within the system boundary; process energy and material balances from commercial simulations and calculation files); electricity EFs (location-specific factors from Ecoinvent); consumables and reagents (background LCI datasets or literature-based proxies); wear parts (embodied emissions derived from metallurgical composition, manufacturing route, and transport); and final concentrate as reference flow. 3.3 Stage 3: Life cycle impact assessment (LCIA) The LCIA uses inventory data to evaluate potential environmental impacts. Although this study evaluates only GWP (expressed in CO2e), other potential impact categories include ozone depletion potential, eutrophication, acidification, and human toxicity. To estimate the final GWP of the product system, the greenhouse gas (GHG) emissions are calculated by multiplying activity data by the appropriate EF, in accordance with NGER Account Factors (2025) [13]: dL( (e2 "##0) = 'fghihgj k4g4 ([m/hg)])×$ohpphq/ ,4fgq1 r+7 Qú2 [I$)> 2%] s (Equation 1) 3.4 Stage 4: Interpretation of the results The final stage involves analysing LCIA results, enabling an overall understanding of the product system. This includes identifying significant issues, evaluating completeness, sensitivity, and consistency, and drawing conclusions and recommendations [2, 3]. The data's accuracy and representativeness must also be verified in accordance with the goal and scope defined in stage 1. The interpretation may also involve sensitivity analyses to determine which aspect, process, or piece of equipment has the most significant impact on the entire process. This is done to identify the greatest opportunities for improvement and to provide
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