In this paper, starting with the st

In this paper, starting with the study of the variation law of CO2 pipeline transportation parameters with temperature and pressure, the supercritical state is determined to be the most suitable state for land pipeline transportation, and then the pipeline characteristics in different states are simulated and analyzed, and the pipeline transportation characteristics under different conditions are obtained respectively, and the following conclusions are drawn:1. Under supercritical conditions, the density and specific heat capacity of carbon dioxide will increase sharply, and the compressibility will also drop sharply, which is similar to that of liquid, while the viscosity and thermal conductivity will drop sharply, which is close to that of gas. All these changes are in the direction of pipeline transportation, so supercritical state is the most favorable state for large-scale and long-distance pipeline transportation.2. There are three ways to realize supercritical carbon dioxide. Under the same molar flow rate, the power consumption and energy consumption from liquid state to supercritical state are the least, while the energy consumption and heat emitted by the system when the gas state is converted to liquid state first and then to supercritical state are far less than those by the method of directly converting the gas state to supercritical state.3. Due to the large pressure drop, the effective transportation distance of the gas pipeline after one pressurization is 37.5km, and the transportation distance of the liquid pipeline is 204.4km due to the limitation of phase state. If the supercritical pipeline wants to keep supercritical, the transportation distance is 128.1km, and if the pressure drop is allowed to be calculated, the transportation distance can reach 1010km. Impurities have little influence on the gas pipeline and the supercritical pipeline, but have great influence on the liquid pipeline. When the distance exceeds 100,