Method of determining the component of a gas in a gas sample

US5849591A · kind A · utility

Assignee

• DRAGERWERK AKTIEGESELLSCHAFT · DE

Inventors

• Wolfgang Bather · Lübeck, DE
• Ingo Kaneblei · Wulfen, DE
• Matthias Martens · Reinfeld, DE
• Andreas Mohrmann · Krummesse, DE
• Ingo Pooch · Ratekau, DE

Key dates

• Filing date: May 13, 1997
• Grant date: Dec 15, 1998
• Expiry date: May 13, 2017

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T436/205831
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The invention is directed to a method for determining the portion of a gaseous or vaporous component in a gas mixture utilizing a detecting substance which can enter into a chemical reaction with the component to produce a coloration of the detecting substance and utilizing a device for evaluating the coloration. The method includes the steps of: passing the gas mixture at a constant volume flow through a channel containing the detecting substance; detecting a reflectance signal I(t) within a defined spatially fixed length segment of the channel; determining a slope .DELTA.I/.DELTA.t at the start of the chemical reaction during a time interval .DELTA.t in which the detecting substance is present in excess; determining a saturation reflectance signal I.sup.100% toward the end of the chemical reaction which corresponds to an almost complete chemical conversion of the detecting substance within the length segment; and, determining a normalized slope in correspondence to the formal relationship: .DELTA.I/(I.sup.100% *.DELTA.t), which is proportional to the portion of the gaseous or vaporous component.