This study evaluates the introduction of Carbon Capture and Utilization (CCU) process in two Colombian refineries, focusing on their potential to reduce CO2 emissions and their associated impacts under a scenario aligned with the Net Zero Emissions by 2050 Scenario defined in the 2023 IEA report. The work uses a MILP programming tool (Linny-R) to model the operational processes of refinery sites, incorporating a net total cost calculation to optimize process perfor-mance over five-year intervals. This optimization was constrained by the maximum allowable CO2 emissions. The methodology includes the calculation of surplus refinery off-gas availability, the selection of products and CCU technologies, and the systematic collection of data from re-finery operations, as well as scientific and industrial publications. The results indicate that inte-grating surplus refinery fuel gas (originally used for combustion processes) and HTL bio-crude off-gas (as a source of biogenic CO2) can significantly lower scope 1 and 2 CO2 emissions, align-ing with long-term decarbonization goals. However, these advantages carry additional costs due to significant increases in utility demands. In the high-complexity refinery, electricity consumption increases by a factor of 16, steam demand by a factor of 2.5, and water usage by a factor of 3. Similarly, in the medium-complexity refinery, electricity consumption rises by a factor of 19, steam demand by a factor of 7, and water usage by a factor of 4. These increases are primarily driven by the renewable energy requirements for water electrolyzers and CO2 capture units. Fur-thermore, despite achieving CO2 neutrality in scope 1 and 2 emissions by 2050, scope 3 emis-sions increase due to additional CO2-based methanol production.

Economic analyses highlight profit opportunities in the long term, as the production costs of CO2-based methanol is lower than forecasted fossil-based cost of production , enhancing their economic viability in the long term. The study emphasizes the critical influence of refinery complexity levels on the scale and timeline for implementing these technologies to achieve short- and long-term CO2 reduction targets. However, further evaluation is necessary to align these results with national electrical grid ca-pacity, water supply availability, and expansion plans.