IN-LINE GAS PURITY MONITORING AND CONTROL SYSTEM

摘要

Apparatus for generating a high purity gas product comprising (a) a proportional flow control/mixing valve having an inlet for a first gas stream comprising a major component and an impurity, an inlet for a second gas stream comprising the major component, and an outlet to supply a mixed gas stream;(b) an analysis zone with sensor to measure the concentration of the impurity in the mixed gas stream and generate a first signal proportional thereto; and (c) control means to recei ve and compare the first signal with a parameter proportional to the concentration of the impurity in the first gas stream and a second parameter proportional to a maximum allowable concentration in the high purity gas product, generate a second signal proportional to the ratio of the first and second parameters, and transmit t he second signal to the proportional flow control/mixing valve to adjust the flow rate s of the first and second gas streams.