METHOD FOR COMPRESSING AN INCOMING FEED AIR STREAM IN A CRYOGENIC AIR SEPARATION PLANT

摘要

A method for compression of an incoming feed air stream using at least two variable speed compressor drive assemblies controlled in tandem is provided. The first variable speed driver assembly drives at least one compression stage in the lower pressure compressor unit driven while the second variable speed driver assembly drives higher pressure compression stage disposed either in the common air compression train or the split functional compression train of the air separation plant. The first and second variable speed driver assemblies are preferably high speed, variable speed electric motor assemblies each having a motor body, a motor housing, and a motor shaft with one or more impellers directly and rigidly coupled to the motor shaft via a sacrificial rigid shaft coupling.

主权项

1. A method for compression of an incoming feed air stream to a cryogenic air separation plant, the method comprising the steps of:
(a) compressing at least a portion of the incoming feed air stream in a lower pressure single stage or multi-stage compressor of a common air compression train, at least one compression stage in the lower pressure single stage or multi-stage compressor driven directly by a first variable speed driver assembly; (b) further compressing the compressed feed air stream in one or more intermediate pressure compression stages of the common air compression train; (c) further compressing the compressed, purified stream in one or more higher pressure single stage or multi-stage compressors of the common air compression train, wherein at least one of the higher pressure single stage or multi-stage compressors are driven by a second variable speed driver assembly; (d) purifying the further compressed feed air stream to remove impurities either after step (a), after step (b), or after step (c); (e) directing one or more portions of the compressed and purified feed air stream to a split functional air compression train; (f) directing the one or more of the portions of the compressed and purified feed air stream in the split functional air compression train to a primary heat exchanger in order to cool the one or more portions to temperatures suitable for rectification in a distillation column system of the cryogenic air separation plant; and (g) directing some or all of the one or more of the portions of the cooled, compressed and purified feed air stream to the distillation column system of the cryogenic air separation plant to produce liquid and gaseous products.