Refining and natural gas processing are among the most carbon-intensive industrial sectors, with CO2 emissions mainly arising from combustion systems, hydrogen production, fluid catalytic cracking, and acid gas treatment. In refineries, combustion-related sources can account for approximately 30–60% of total CO2 emissions, while hydrogen production and fluid catalytic cracking typically contribute 10–20% and 15–25%, respectively. This review evaluates the integration of carbon capture, utilization, and storage (CCUS) with blue hydrogen production as a practical pathway for reducing emissions in refineries and gas processing plants. Major capture routes, including post-combustion, pre-combustion, and oxy-fuel systems, are compared in terms of technical performance, energy demand, and deployment suitability. Typical capture efficiencies range from 85% to 95%, with solvent regeneration energy requirements of 2.5–4.0 GJ/tCO2 and CO2 compression demand of 0.08–0.12 MWh/tCO2. Blue hydrogen produced from steam methane reforming or autothermal reforming with CO2 capture can reduce hydrogen carbon intensity from 9–12 kg CO2/kg H2 for grey hydrogen to about 1–4 kg CO2/kg H2, provided that upstream methane leakage is minimized. Economic benchmarks indicate that capture costs vary from approximately $15–40/tCO2 for high-purity natural gas processing streams to $50–80/tCO2 for hydrogen production and $70–120/tCO2 for dilute refinery flue gases. Overall, integrated CCUS and blue hydrogen systems provide a scalable near- to medium-term decarbonization pathway, especially when prioritized for high-concentration CO2 streams and supported by shared transport and storage infrastructure.