Device and method for removing heavy hydrocarbon in natural gas through step-by-step condensation

Abstract

The invention discloses a method for removing heavy hydrocarbon in natural gas through step-by-step condensation. The method mainly comprises the processes that after decarburization and dehydration are conducted on the natural gas, the natural gas enters a shallow cooling separation system to be cooled to about -30 DEG C, and first-step heavy hydrocarbon separation is conducted; the natural gas with partial heavy hydrocarbon removed enters a copious cooling tank again to be further cooled to about -60 DEG C, then second-step heavy hydrocarbon removal is conducted, and through a two-step heavy hydrocarbon separation technology and device, the natural gas can completely meet the requirements for the content of the heavy hydrocarbon of natural gas copious cooling liquidation. According to the method, cooling separation is conducted twice for natural gas heavy hydrocarbon removal, the technology is mature, the adaptability is high, and the method is particularly suitable for a modification technology which cannot meet liquidation requirements due to the fact that the content of heavy hydrocarbon in virgin gas components is high and the fluctuation range is wide; meanwhile, the load of a liquidation system of an existing natural gas liquidation factory can be reduced and the liquidation capacity of the existing natural gas liquidation factory can be improved.

Description

technical field [0001] The invention relates to a device and method for removing heavy hydrocarbons in natural gas by stepwise condensation. Background technique [0002] With the development and utilization of clean energy getting more and more attention, the development of natural gas is favored. However, the infrastructure of China's natural gas industry is still relatively weak, and the laying of natural gas pipeline networks cannot keep up with the growth rate of consumption, which restricts the utilization and development of natural gas. The convenient transportation characteristics of liquefied natural gas (LNG) can greatly alleviate this contradiction. Therefore, many new natural gas liquefaction plants have been built in China in recent years. However, heavy hydrocarbons often condense in the cold box during the natural gas liquefaction process, causing the cold box to freeze and block, which seriously affects the normal operation of the natural gas liquefaction pl...

AI Technical Summary

Problems solved by technology

Therefore, in recent years, many new natural gas liquefaction plants have been built in China. However, heavy hydrocarbons often condense in the cold box during the natural gas liquefaction process, causing the cold box to freeze and block, which seriously affects the normal operation of the natural gas liquefaction plant and may lead to safety accidents.

Images