Wobbe Index, BTU Calorimeter

The COSA 9610™ Wobbe Index Meter's measuring principle is based on the analysis of the oxygen content in the flue gas after combustion of the sample. A continuous gas sample is mixed with dry air at a precisely maintained constant ration, which depends on the BTU range of the gas to be measured. The fuel air mixture is oxidized in a combustion furnace in the presence of a catalyst at 800’C, and the oxygen concentration of the combusted sample is measured by a zirconia oxide cell. The residual oxygen provides an accurate measurement for the Combustion Air Requirement (CARI) of the sample gas, which can be correlated accurately to the Wobbe Index of the gas.

Wobbe Index, BTU Calorimeter


  • High Accuracy
  • Fast Response
  • Large Measurement Range
  • Measures Low BTU Gases
  • Low Maintenance
  • Flameless / No Flameouts
  • Measures Wobbe and CARI
  • CSA Approval Optional
  • Direct Measurement Method ( ASTM D-4891 Compliant )
  • Gross or Net Heating Values

Technology Used

Typical Applications

  • Turbine Control
  • Flare Stack Control
  • Fuel Optimization
  • Gas Blending
  • Custody Transfer
  • Hyco Plant Control
  • Hydrogen Applications
  • Air Blending Applications