Correlative comparison of gas CO2 pipeline transportation and natural gas pipeline transportation

Carbon capture, utilization and storage technology (CCUS) is considered to be one of the most important technical pathways for greenhouse gas emission reduction. CO2 pipeline transportation technology in China started late, with more CO2 pipeline transmissions operating in the gas-phase. At present, the main reference for the design of CO2 gas transmission pipeline is the standard of natural gas pipeline. Because of the differences of physical properties between CO2 and natural gas, there are many problems in pipeline design. This paper makes a comparative analysis of CO2 and natural gas related physical properties and transport parameters in China. The results showed that compared with natural gas, CO2 has a mutation in the density, viscosity, heat capacity and liable to phase changes, so the temperature and pressure in the process of conveying should be strictly controlled. At the same time, compared with natural gas, the explosion of CO2 is relatively safe, but the CO2 has strong corrosion at the existence of water, so in the design of CO2 pipeline the difference of the safety level and corrosion should be considered. Under the same conditions, the gas phase transport of CO2 mixture is more likely to generate hydrate than natural gas. The study provides some suggestions for the construction of CO2 pipeline transportation in China.