2651 Table 5 – Cu-case GWP results (per plant unit and entire product system) Plant unit GWP results (CO2e emissions) Unit Primary grinding 31 739 (kg CO2e/h) Secondary grinding 25 607 Rougher flotation 11 615 Regrinding 2 179.1 Cleaner flotation 1 670.7 Concentrate dewatering 299.01 Tailings dewatering 3 445 Total 76 555 (kg CO2e/h) Concentrate production 63.4 (t/h) Final LCA result [ref: product] 1 207 (kg CO2e / t Cu con) Final LCA result [ref: ore feed] 25.1 (kg CO2e / t ore feed) The copper concentrator emits approximately 76,555 kg CO2e/h at a production rate of 63.4 t/h of concentrate, corresponding to 1,207 kg CO2e/t of concentrate. When expressed per tonne of ore feed, the intensity is 25.1 kg CO2e. The same methodology was followed for the iron and lithium cases (Table 6). Table 6 – All case studies GWP results Unit GWP results (CO2e emissions) Copper Iron ore Lithium Total CO2e emissions (kg CO2e / h) 76 555 37 079 2 274 Concentrate production (t con / h) 63.4 3 003.0 21.8 Ore feed rate (t ore / h) 3 044.0 6 492.0 336.4 Final LCA result [ref: product] (kg CO2e / t con) 1 207 12.3 104.3 Final LCA result [ref: ore feed] (kg CO2e / t feed) 25.1 5.7 6.8 The iron concentrator (situated in Brazil) includes a HPGR and ball milling units, magnetic separation, desliming, flotation (rougher, cleaner, scavenger), regrinding, and dewatering sections. The plant emits approximately 37,079 kg CO2e/h at 3 003 t/h of concentrate, equating to 12.3 kg CO2e/t of concentrate and 5.7 kg CO2e/t of ore feed. The lithium plant (Finland) comprises crushing, ore sorting, grinding, magnetic separation, preflotation, spodumene flotation (rougher and cleaner), dewatering, and tailings dry stacking. The inclusion of crushing enables a fuller gate-to-gate perspective. This plant emits approximately 2,274 kg CO2e/h at 21.8 t/h of concentrate, corresponding to 104.3 kg CO2e/t of concentrate and 6.8 kg CO2e/t of ore feed. 4.4 Stage 4: Interpretation of the results Figure 2 illustrates the emission results by showing the contribution of each source—electricity consumption, wear, and reagent use—to the total emissions of the copper processing plant. It also expresses the results associated with each plant unit, namely grinding, beneficiation, and dewatering. It indicates that electricity was the dominant contributor to the overall GHG emissions in the evaluated copper concentrator case study. Its contribution was estimated to be approximately 72% (871 of the total 1,207 kg CO2e per Cu concentrate). This underscores the substantial impact that an inaccurate EF can have on results and emphasises the significant role of electricity in total GHG emissions. The figure also displays total emissions by plant unit and shows that the grinding unit has the greatest impact on the copper plant's total emissions, accounting for 72% of total emissions due to its significant electricity consumption. Understanding the
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