In the field of CO₂ capture and sequestration, ensuring the safety of pipeline infrastructure is paramount to successful climate change mitigation efforts. This study investigates the dynamics of CO₂ dispersion from pipeline systems, assessing not only the transport process but also the physical properties and associated hazards. Advanced simulation techniques are used to model how different states of CO₂ (gas, liquid, and supercritical) and varying pipeline characteristics—such as perforation sizes, flow rates, and orientations—affect the dispersion patterns in the event of a leak. Simulations cover a range of atmospheric conditions, emphasizing the role of atmospheric stability and wind speed in shaping dispersion and defining potential impact zones. An analysis of historical pipeline accidents is included to inform risk management strategies. The results show that the orientation of the pipeline has a significant effect on dispersion, with downward leaks causing the largest impact zones, particularly under supercritical conditions. The results highlight the need for adaptive safety strategies that take into account real-time CO₂ transport conditions and localized environmental data. By integrating these factors, the study recommends refining safety protocols and emergency response strategies to improve pipeline resilience and public safety against potential leaks. Key findings include the quantification of the relationship between leak parameters and dispersion areas, providing a valuable framework for future safety improvements.

In order to fight climate change, the EU has set a goal of achieving net-zero greenhouse gas emissions by 2050. To achieve carbon neutrality, greenhouse emissions from human activities should be at least 85% lower than in 1990. The remaining 15% can be achieved through additional measures such as increasing carbon capture and storage (CCS) and reducing emissions. CCS will facilitate the decarbonization of heavy industry, contribute to the emergence of a clean hydrogen economy, and aid in achieving net-zero emissions. As an emerging technology in the Industry 4.0, digital twin (DT) is gaining attention due to the possibilities arising from its application, such as precise process optimization in the design phase, quality control, monitoring, decision-making, and through comprehensive modeling of the physical world as a group of connected digital models. The introduction of digital technologies into the CCS sector has the potential to revolutionize the way CO2 capture, transportation, and storage processes are carried out. This article aims to present the fundamental value of different modeling techniques, technologies enabling the creation of DT’s uncertainty quantification methods commonly used in Digital Twins, as well as the application of Digital Twin in CCS technology and the potential benefits it can bring, including increases efficiency and cost minimization. Additionally, the possibilities of using DS’s in improving process monitoring and forecasting were discussed which can contribute to better emission control and increases system effectiveness. Current research and projects utilizing this technology were also presented, including real-time modeling of fluid flow, CO2 transport network optimization and storage process improvement.

Regulatory changes related to the policy of reducing CO₂ emissions from natural gas are leading to an increase in the share of hydrogen in gas transmission and utilization systems. In this context, the impact of the change in composition on thermal radiation zones should be assessed for flaring during startups, scheduled shutdowns, maintenance, and emergency operations. Most existing models are calibrated for hydrocarbon flare gases. This study assesses how the CH₄–H₂ blends affect thermal radiation zones using a developed solver based on the Brzustowski–Sommer methodology with composition-dependent fraction of heat radiated (F) and range-dependent atmospheric transmissivity. Five blends, 0–50% (v/v) H₂, were analyzed for a 90 m stack at wind speeds of 3 and 5 m·s⁻¹. Comparisons were performed at constant molar (standard volumetric) throughput to isolate composition effects. Adding H2 contracted the radiation zones and reduced peak ground loads. Superposition analysis for a multi-flare layout indicated that replacing one 100% (v/v) CH₄ flare with a 10% (v/v) H₂ blend reduced peak ground radiation. Emission-factor analysis (energy basis) showed reductions of 3.24/3.45% at 10% (v/v) H₂ and 7.01/7.44% at 20% (v/v) H₂ (LHV/HHV); at 50% (v/v) H₂, the decrease reached 22.18/24.32%. Hydrogen blending provides coupled safety and emissions co-benefits, and the developed framework supports screening of flare designs and operating strategies as blends become more prevalent.

Quantitative risk assessment (QRA) of high-pressure CO₂ pipelines depends on a chain of assumptions concerning failure frequencies, transient release modelling, near-field transformation, atmospheric dispersion, and human-harm criteria. This paper presents a problem-oriented review of these modelling stages and proposes criteria for evaluating model applicability, validation range, computational requirements, and coupling consistency. The review is supplemented by an illustrative case using the DNV Phast 8.61 Long Pipeline model and Unified Dispersion Model for five perforation diameters and four concentration levels. Dangerous toxic load calculations yielded equivalent constant concentrations of 64,033–114,353 ppm for fatality probabilities of 1–50% and exposure durations of 5–30 min. Increasing the assumed exposure duration from 5 to 30 min reduced the equivalent thresholds by approximately 20.1%. Under the adopted perforation-size weighting, the 30 mm class accounted for 69.4% of punctures, showing that the largest analysed perforation does not necessarily carry the largest frequency contribution. The case is illustrative rather than site-specific and does not benchmark alternative models. The proposed framework supports transparent, proportionate QRA for pipeline design, land-use planning, emergency preparedness, and sustainable CCUS deployment.