System for preventing contaminants from reaching a gas purifier

A system for purifying a conventional purity gas stream to an ultra-high purity level thereby producing an ultra high purity gas stream and supplying said ultra high purity gas stream continuously, while protecting the system from an exothermic reaction, comprising:

• (a) producing a conventional purity gas stream using an air separation unit to separate the gas stream supplied to the separation unit from contaminants;
• (b) routing the conventional purity gas stream exiting the air separation unit to a gas purifier to further remove contaminants;
• (c) measuring the concentration of a contaminant in the conventional purity gas stream using at least one contaminant detection device disposed on a line leading the conventional purity gas stream from the air separation unit to the gas purifier;
• (d) providing at least one buffer volume downstream of the contaminant detection device wherein the buffer vessel is sized to hold-up a predetermined volume of the conventional purity gas prior to routing the conventional purity gas stream to the gas purifier such that if the contaminant concentration detected upstream of the buffer vessel exceeds a predetermined level, the contaminated conventional purity gas stream can be prevented from reaching the gas purifier and causing an exothermic reaction.