Patent · US Expired

Carbon dioxide measurement system

US4321545A · kind A · utility

7Cited by
5References
2Claims
0Family size

Inventor

Key dates

Filing dateMar 13, 1980
Grant dateMar 23, 1982
Priority date
Expiry dateMar 13, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N27/06
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus wherein a sample of gas or fluid containing carbon dioxide in the form of dissolved carbon dioxide gas, bicarbonate ion, and/or carbonate ion is injected into an extraction chamber provided with an acid extracting fluid. A carbon dioxide-free gas stream is passed through the extraction chamber in order to carry the dissolved CO.sub.2 gas formed from bicarbonate and carbonate ions, as well as that already present, onto a spiral absorbing column, wherein a dilute alkaline solution absorbs the CO.sub.2 with a resulting change in electrical conductivity of the alkaline solution. The system disclosed provides electrical means for measuring the conductivity difference thus produced, means for conversion of this difference to an appropriately coded electrical signal, and means for providing a direct display of the sample concentration. Means are provided for indicating when a sample is being processed by the apparatus, and for holding the displayed concentration until manually re-set. Two types of extraction chambers are disclosed, one for gas and non-foaming liquids, and a second for foaming liquids such as blood. The method and apparatus is suitable for use with s…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.