Multi-channel on-line chromatographic analysis system for quick air-fuel ratio measurement

摘要

Details of the design and construction of a two-channel air-fuel ratio (APR) chromatograph for the on-line analysis of a single sample of wet combustion gases are given. A thermal conductivity detector (TCD) is used to detect CO, and N, components, which are separated on a single column system. Then the ratio of the concentration of CO, and N, is used to determine the APR in the original sample. The column used is a stainless-steel tube (3 in X 1/8 in. I.D.) filled with 80 mesh Porapak Q. A switchingvalve is incorporated to divert the samples between the separating column. The instrument is fully automatic and capable of determining two different APR measurements in a working time of less than 5 s. It can operate satisfactorily at mixture strengthsthat are well above stoichiometric levels.