NEW TYPE OF MOLECULAR SIEVE WITH LONGER LIFEFOR NATURAL GAS DRYING

摘要

It has been observed in many natural gas drying units that the carryover of liquidshas a damaging effect on mechanical strength of the molecular sieves. Pressure dropincreases a well as reduced cycle times have been observed.The molecular sieve degradation by liquid carry over has been thoroughlyinvestigated. It occurs at high temperature during the heating step and affects the zeolitecrystallinity as well as the binder cohesion. A new type of molecular sieve, whichexhibits a greater intercrystal stability, has been developed; besides its liquid carryoverresistance, it has shown an interesting behaviour in minimising coking.Consequently, the new absorbent type has been installed in a turbo expander plantat Lacq - France, where such problems occurred in the past, and confirmed the expectedperformances. Longer cycle times and pressure drop levels within design limits allow alonger life for the molecular sieve.