When transporting pure carbon dioxi

When transporting pure carbon dioxide by pipeline, its state mainly includes gaseous state, liquid state and supercritical state. Because the density of gas itself is small, when transporting carbon dioxide with the same mass, the occupied pipeline size is large, and because of the large friction between gas and pipeline, the pressure drop of the pipeline is also high, so it is not conducive to transportation when transporting gas on a large scale and in a long distance, while the temperature in the pipeline needs to be kept low when transporting liquid, but due to the change of external conditions, the phase state of the medium is easy to change during transportation, that is, the liquid becomes gas. In this way, there will be gas-liquid two-phase flow in the pipeline, and the performance of the pipeline will be greatly reduced. Therefore, thermal insulation measures are required for liquid transportation. Usually, the state of carbon dioxide produced by wellhead is supercritical, where most of the pressure energy can be effectively utilized, and carbon dioxide has many characteristics conducive to pipeline transportation in supercritical state, so supercritical transportation has become the first choice for pipeline transportation of carbon dioxide.