Influence of pipeline transportation conditions on the cascading utilization benefit of LNG cold energy

In order to broaden the site selection range of the cold energy utilization plants and realize the collaborative coupling between LNG pipeline transportation and cold energy utilization, the technical process of LNG pipe transportation and cascading cold energy utilization was simulated and calculated in this paper. A coupling model for the LNG supercooled pipeline transportation and cascading cold energy utilization was established based on the simulation software HYSYS of chemical process. The influences of pipe diameter and cold-keeping layer thickness on cold transportation distance and construction cost at the constant transportation were analyzed by using the phase equilibrium ability of PR equation. The economic effects of pipeline transportation distance on cascading cold energy utilization were analyzed. It is shown that at the constant transportation, the small diameter transportation scheme with pressure drop as the main influencing factor of LNG gasification is short in transportation distance and low in the cost of unit pipe length, so increasing the cold holding grade has no significant influence on the transportation distance. The first stage cold energy utilization process which takes LNG latent heat as the main cold source is economically the most sensitive to the transportation distance, and its economic benefit decreases with the increasing of transportation distance.