A temperature-compensated CO2 detection system based on non-dispersive infrared spectral technology

Area of Science:

• Engineering
• Environmental Science
• Analytical Chemistry

Background:

• Carbon dioxide (CO2) concentration is a critical safety indicator in coal mines.
• Existing CO2 detection equipment suffers from poor portability and high costs.
• Real-time monitoring is essential for proactive accident prevention.

Purpose of the Study:

• To develop a miniaturized, cost-effective CO2 detection system for coal mine safety.
• To enhance the portability and sensitivity of CO2 monitoring devices.
• To improve the accuracy and reliability of CO2 measurements in dynamic environments.

Main Methods:

• Utilized non-dispersive infrared (NDIR) technology with an integrated infrared light source and dual-channel pyroelectric detector.
• Designed a reflective gas chamber for an extended optical path and increased sensitivity.
• Implemented hardware and software filtering to mitigate noise interference.
• Parametrically corrected the Lambert-Beer law and established a dual-channel voltage ratio-concentration model.
• Incorporated temperature compensation for zero and span values.

Main Results:

• The system accurately measures CO2 concentrations from 0 to 50,000 ppm within 0-40°C.
• Achieved a maximum detection error of less than 0.12% and repeatability deviation below 1.04%.
• Demonstrated excellent stability with a maximum concentration drift of 0.07% over 12 hours.

Conclusions:

• The developed miniaturized NDIR system meets coal mine safety monitoring requirements.
• The system offers a portable, cost-effective, and highly accurate solution for real-time CO2 detection.
• The enhanced sensitivity, noise mitigation, and temperature compensation contribute to reliable performance.