LNG cold energy gradient utilization method for recovering light hydrocarbon by adopting cold energy

Abstract

The invention discloses a LNG cold energy gradient utilization method for recovering light hydrocarbon by adopting cold energy. The method comprises the following steps: (S1) the light hydrocarbon isrecovered by using LNG cold energy; (S2) the oil field associated gas condensate recovery or the liquefied CO2 and dry ice preparation or the low-temperature crushing of waste rubber is performed by using the LNG cold energy after recovery of the light hydrocarbon; and (S3) the warehouse refrigeration or the seawater desalination is performed by using the LNG cold energy after the oil field associated gas condensate recovery or the liquefied CO2 and dry ice preparation or the low-temperature crushing of the waste rubber. The method has the following beneficial effects: under the precondition of meeting different user operation characteristics, optimal configuration of the cold energy among multiple users is arranged to realize gradient utilization of the cold energy. According to demands of various cold energy utilization processes on temperature levels, three grades of utilization schemes are formulated, so that the LNG cold energy recovery rate is increased, the LNG vaporization costis reduced, and important significance on improvement of the energy utilization efficiency is achieved.

Description

technical field [0001] The invention relates to the technical field of LNG cold energy utilization, in particular to a method for cascaded utilization of LNG cold energy by recovering light hydrocarbons from the cold energy. Background technique [0002] Since the beginning of the 21st century, the world's oil prices have soared, and energy and electricity costs have increased significantly. In the form of China's rapid economic development, it is imperative to save energy and improve energy utilization. As a clean and efficient energy source, LNG is favored by countries all over the world, which has also brought about the rapid development of the LNG industry (an average annual growth rate of 20%). [0003] LNG is a low-temperature (-162°C) liquid mixture made of low-pollution natural gas after deacidification and dehydration treatment, and freezing and liquefaction through a low-temperature process. Its density is increased by about 600 times to facilitate long-distance tr...

AI Technical Summary

Problems solved by technology

At present, in the utilization of cold energy of LNG, there are low utilization efficiency of cold energy, Due to the large loss phenomenon, most of the cold energy carried by LNG has not been rationally utilized

[0006] At present, the design of some cascade cold energy utilization processes lacks strong theoretical arguments, or there is a disconnect between theory and actual utilization. The cascade utilization of LNG cold energy is only studied from the perspective of energy, while the quality of LNG cold energy is ignored, resulting in the actual Cold storage of LNG utilization process in utilization The efficiency is very low, there is a phenomenon that the cold energy of LNG has not been reasonably and fully utilized, and the high-quality cold energy in the lower temperature range is used in a process that requires low cold energy grade, resulting in a significant reduction in the effect of cold energy utilization

[0007] Although the cascade cold energy utilization process has been proposed, it still has not been able to fundamentally solve the problems of low utilization efficiency and low economic benefits of LNG cold energy

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