WATER REMOVAL AND HEAVY-HYDROCARBON REMOVAL PROCESS IN LIQUEFIED NATURAL GAS PRODUCTION FROM MIXED GAS RICH IN METHANE

摘要

A process for dehydrating and removing heavy hydrocarbons in the production ofliquefiednatural gas from a methane-rich gas mixture is disclosed, wherein the methane-rich gas mixturesubjected to deacidification treatment is divided into two streams, i.e. thefirst stream and thesecond stream, wherein the first stream used as a system process gas isintroduced into a dryingprocedure, and the second stream used as regenerating gas is introduced into aregeneratingprocedure; the first stream is subjected to a drying treatment, and themoisture and the heavyhydrocarbons are simultaneously removed from the first stream in a compositeadsorbent bed(s)of a drying tower, wherein the moisture is removed such that the dew point atnormal pressure is= -76°C and the heavy hydrocarbon components of C6 and higherare removed such that thecontent of these components is = 217ppm; and the second stream is usedas a regenerating gas inthe regenerating procedure of the above-mentioned drying tower, subjected to aregeneratingprocess, and then returned as a part of the system process gas. Comparing tothose conventionalprocesses, the present invention can achieve good purifying effect, lowerequipment investmentand late-stage energy consumption of the system, increase utilization ratio offeed gas, and theoperation target of each unit becomes more clear and easy to control. Thepresent inventionfurther relates to an apparatus for carrying out the process.