Basic Working and Operation

Gas analyzers are instruments used to detect and measure the concentration of gases in a sample. They play a crucial role in monitoring and controlling air quality, industrial processes, and emissions. Gas analyzers can be based on various principles such as infrared absorption, chemiluminescence, electrochemical, and more.

Components:

  • Sample Inlet: Where the gas sample is introduced.
  • Sensor/Detector: Converts the gas concentration into a measurable signal.
  • Signal Processor: Processes the signal from the sensor.
  • Display/Output: Shows the measured gas concentration or transmits the data for further analysis.

Operation:

  • The gas sample is drawn into the analyzer through the sample inlet.
  • The sensor detects the presence and concentration of specific gases in the sample.
  • The signal processor converts the sensor’s output into a readable format.
  • The concentration is displayed on the screen or transmitted to a control system.

Types of Gas Analyzers

Infrared (IR) Gas Analyzers:

Principle: Absorption of infrared light by gas molecules.

Applications: Measuring CO2, CO, CH4, and other hydrocarbons.

Example: Monitoring CO2 levels in industrial emissions.

 

Chemiluminescence Gas Analyzers:

Principle: Emission of light during a chemical reaction.

Applications: Measuring nitrogen oxides (NOx).

Example: Analyzing NOx in vehicle exhaust emissions.

 

Electrochemical Gas Analyzers:

Principle: Chemical reaction producing an electrical signal.

Applications: Detecting O2, CO, H2S, and other toxic gases.

Example: Monitoring oxygen levels in confined spaces.

 

Flame Ionization Detectors (FID):

Principle: Ionization of gas molecules in a flame.

Applications: Measuring total hydrocarbons.

Example: Monitoring hydrocarbon emissions in refineries.