LNG管输优化的经济数学模型

Economic mathematical model for optimization of LNG pipeline

LNG是一种多组分混合物,外界环境的漏热会引发诸多问题,影响管输的安全性和经济性。了解漏热状态下LNG蒸发率和压力的变化规律,对LNG管道设计和管理具有重要的理论意义。基于LNG管道输送过程中保温层厚度、LNG气化率、管道壁厚之间的变化规律,采取冷态输送法,通过采用合理的保温层厚度控制LNG的蒸发,从而使管内压力升高,以此推动LNG向前流动,从而优化管输工艺。建立了LNG管输优化的经济数学模型,计算获得系统的最佳气化率以及最佳管壁和保温层厚度,从而优化了管输系统的经济费用。实例计算验证了该模型和计算程序的工程应用价值。

LNG is a multi-component mixture and its heat leakage to outside can cause many problems and influence the safety and economy in pipeline transmission. In the case, understanding the change law of LNG evaporation rate and pressure under heat leakage has great theoretical significance in the design and management of LNG pipeline. Based on the change laws in insulating layer thickness, LNG vaporization ratio and thickness of pipe wall, adopting cold-state transport method should be made to increase pipeline pressure by controlling the thickness of thermal insulation materials in order to eliminate LNG's vaporization, which will be an available way to promote flowing of LNG and optimize transport technology. Establishing the economic mathematical model for LNG pipeline transport to obtain the best vaporization ratio and thicknesses for pipe and thermal insulation layer is important, and the economy and cost of pipeline systems can be optimized by this way. Adaptability for the model and its calculation program in pipeline project is given with a case.