Patent ID: 7228715
Filing Date: 2007-06-12
Classification: F25J

Abstract:
1. A low temperature air separation process for producing pressurized gaseous product in an air separation unit using a system of distillation columns which comprises the following steps: a. Cooling a compressed air stream in a heat exchange line to form a compressed cooled air stream b. Sending at least part of the compressed, cooled air stream to a column of the system c. In a first period of time, liquefying a process stream to form a first liquid product and storing at least part of this first liquid product d. In a second period of time, sending the above stored first liquid product to the air separation unit as one of the feeds e. Pressurizing at least one second liquid product stream f. Vaporizing the above pressurized second liquid product stream in the heat exchange line to form pressurized gaseous product g. During the above second period of time, extracting a cold gas from the air separation unit at a temperature between −195° C. and −20° C. wherein the cold gas is removed from the air separation unit after being cooled by traversing the warm end of the heat exchange line only.