SOURCE CHARACTERISATION OF CO₂ EMISSIONS IN PETROLEUM REFINERIES IN PORT HARCOURT: RELEVANCE FOR CARBON CAPTURE AND STORAGE

This study assessed the sources, operational drivers, and feasibility of implementing carbon capture and storage (CCS) at the refinery. Data were collected from 18 staff members, including engineers, environmental officers, operations managers, and maintenance personnel, through structured questionnaires and semi-structured interviews, supplemented by secondary reports. Respondents estimated annual CO₂ emissions between 1–5 million tonnes, with the fluid catalytic cracking (FCC) unit (29.8%), fired heaters/boilers (27.2%), and steam methane reforming (SMR, 19.1%) identified as the primary contributors. Reported CO₂ concentrations in flue gases ranged from 5–15%, with FCC and SMR units exhibiting 8–12% and 12–15%, respectively, indicating suitability for post-combustion capture technologies. Energy consumption was concentrated in FCC (120–150 MW/day), boilers (80–100 MW/day), and SMR units (60–70 MW/day), further highlighting their role as major emission drivers. Capacity utilization post-2024 rehabilitation was 53.3% for the New Plant and 41.7% for the Old Plant, reflecting underutilization and operational instability. While 44% of staff demonstrated familiarity with CCS and identified existing natural gas pipelines and compression infrastructure as adaptable for CO₂ transport, 56% had limited or no knowledge, indicating gaps in technical readiness. The study concludes that targeted CCS implementation at high-emission units is technically feasible, but successful deployment requires enhanced monitoring systems, workforce training, and infrastructural assessment. These findings provide critical insights for policymakers and refinery management in Nigeria and contribute to strategies for emissions reduction in oil and gas operations in emerging economies.