Infrared Gas Analyzers

Description

Key Components and Functionality:

1. Infrared Source: Emits infrared radiation across a specific wavelength range.
2. Sample Cell: Contains the gas sample to be analyzed.

3. Detector: Measures the intensity of the infrared radiation transmitted through the sample cell.

4. Optical System: Guides the infrared radiation through the sample cell and to the detector.

5. Electronics: Processes the detector signal, converts it into a concentration reading, and displays the results.

Types of Infrared Gas Analyzers:

• Non-Dispersive Infrared (NDIR) Analyzers:

  • Employ a filter to select a specific wavelength of IR radiation that is strongly absorbed by the target gas.
  • A reference cell filled with the target gas is used to compensate for variations in the IR source intensity.

  • Simple, robust, and widely used for measuring gases like CO2, CO, and CH4.

• Fourier Transform Infrared (FTIR) Analyzers:

  • Utilize an interferometer to split the IR radiation into two beams, which are then recombined to create an interference pattern.
  • Fourier Transform analysis of this interference pattern yields the complete infrared spectrum of the sample.

  • Highly versatile, capable of identifying and quantifying multiple gases simultaneously.

Applications:

• Environmental Monitoring: Measuring greenhouse gases, air pollutants, and other atmospheric gases.
• Industrial Process Control: Monitoring and controlling combustion processes, optimizing fuel efficiency, and ensuring emissions compliance.  

• Medical Applications: Analyzing respiratory gases for diagnostic purposes.
• Scientific Research: Studying atmospheric chemistry, climate change, and other environmental phenomena.

Advantages:

• High Sensitivity and Specificity: Can detect and quantify trace amounts of gases with high accuracy.
• Non-Destructive: The measurement process does not alter the sample.

• Versatility: Suitable for measuring a wide range of gases in various environments.

Limitations:

• Interference from other gases: Some gases may absorb IR radiation at similar wavelengths, potentially interfering with the measurement.
• Limited to IR-active gases: Only gases that absorb IR radiation can be measured