Natural gas liquefaction process

Abstract

The invention discloses a natural gas liquefaction technique which comprises a pretreatment unit (10), a compression unit (11), a liquefaction unit (12), a storage unit (13) and a loading unit (14). The technique mainly comprises the steps: (1) large grained impurities contained by the raw material natural gas can be firstly separated by the pretreatment unit (10), and the moisture is removed; (2) after being processed by the pretreatment unit (10), the natural gas enters the compression unit (11) to be compressed into 10-25MPa; (3) after being pressurized, the natural gas enters the liquefaction unit (12) to be transformed into liquid natural gas LNG; (4) the liquid natural gas LNG is input into the storage unit (13) to be stored; (5) the liquid natural gas LNG in the storage unit (13) is loaded by the loading unit (14). By the improvement of the compression unit and the liquefaction unit of the existing technique, one-off liquefaction rate is effectively improved, and the liquefaction cost can be reduced.

Description

technical field [0001] The invention belongs to the technical field of gas liquefaction systems, and in particular relates to a natural gas liquefaction process. Background technique [0002] At present, the natural gas liquefaction process includes a pretreatment unit 10, a compression unit 12, a liquefaction unit 13, a storage unit 14, and a loading unit 15. The main steps are: [0003] (1), the raw natural gas first passes through the pretreatment unit 10 to separate the large particles of impurities it contains and remove moisture; [0004] (2), the natural gas processed by the pretreatment unit 10 enters the compression unit 12 to be compressed to 10-25MPa; [0005] (3), the pressurized natural gas enters the liquefaction unit 13 to be converted into liquid natural gas LNG; [0006] (4), liquefied natural gas LNG input storage unit 14 preserves; [0007] (5), the liquefied natural gas LNG in the storage unit 14 is loaded through the loading unit 15 . [0008] A comp...

AI Technical Summary

Problems solved by technology

[0012] 1. The refrigeration device has complex structure, large volume and complicated operation;

[0013] 2. When the refrigeration equipment is working, the equipment needs to run at high speed, resulting in poor system reliability;

[0014] 3. The primary liquefaction rate of the expansion machine refrigeration cycle is low. The theoretical value is between 8% and 12%, usually around 9%. Therefore, the energy consumption of full liquefaction is relatively high

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