The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 25, 1997
Filed:
May. 24, 1996
Atsushi Fujita, Kawasaki, JP;
Morimitsu Nakamura, Kawasaki, JP;
Nippon Sanso Corporation, Tokyo, JP;
Abstract
The present invention offers a pre-purification method and apparatus for an air cryogenic separation plant for removing water vapor and carbon dioxide from feed air, which is able to operate at high air temperatures without the use of special installations such as pre-cooling equipment or demoisturizers to replace freon refrigerators or water spray cooling columns. One aspect of the present invention is a pre-purification method for an air cryogenic separation plant which continuously purifies feed air using a plurality of reciprocally-used adsorption columns 5a, 5b filled with adsorbents for adsorption removal of water vapor and carbon dioxide from the feed air. The method includes an adsorption step, a depressurization step, a heating step, a cooling step, and a repressurization step, whereof the adsorption step for adsorption removal of impurities is performed by feeding pressurized feed air at a temperature of 10.degree..about.45.degree. C. into an adsorption column filled with water adsorbent and carbon dioxide adsorbent arranged respectively in that order from the air entrance, at a superficial velocity of 5.about.40 cm/s. Another aspect of the present invention is a pre-purification apparatus for an air cryogenic separation plant having adsorption columns 5a, 5b filled with water adsorbent and carbon dioxide adsorbent arranged respectively in that order from the air entrance, wherein the weight ratio of the water adsorbent to the total amount of adsorbents is 0.4.about.0.7.