Combustible gas sensor
As the primary energy source in production and daily life, combustible gases are prevalent in various industrial processes and everyday environments. Common flammable gases include hydrogen, carbon monoxide, methane, propane, ethylene, hydrogen sulfide, among others. It’s important to note that many of these flammable gases are also toxic and harmful, such as carbon monoxide, hydrogen sulfide, chlorine, and others.
When the concentration of these flammable gases exceeds a certain threshold, they can pose a risk of explosion and fire accidents. Detecting and monitoring these gases requires specific analysis based on the particular situation.
Choosing the right combustible gas sensor
Different application scenarios have different requirements for gas detectors, and they also have different requirements for their core component – gas sensors. How to choose a suitable Combustible gas sensor for our detector?
Semiconductor type:
In general household settings, there is a need to quickly detect low-concentration flammable gas leaks and trigger a single-point alarm. Additionally, it should be maintenance-free for an extended period and convenient for home use. Semiconductor combustible gas sensors offer a lower detection limit, longer service life, and undergo only gas adsorption and desorption during the detection process. The presence of heavy kitchen oil fumes has minimal impact on the sensitive material’s surface, ensuring the sensor’s actual service life. Consequently, semiconductor sensors are the best choice for home alarms.
Catalytic combustion type:
Catalytic combustible gas sensor are widely used worldwide, featuring fast response times. These sensors provide output nearly proportional to the gas concentration up to the lower explosion limit (LEL), offering high accuracy and repeatability. They are suitable for quantitative detection in industries such as coal mines, petroleum, chemicals, and gas. However, catalytic combustion sensors operate at high temperatures and can be prone to catalyst deactivation. Additionally, silicone and sulfide released from adhesives and rubber products in the surrounding environment can poison the catalyst, leading to sensor failure. In industrial environments, regular calibration using standard gases and adjustment of amplification are necessary to prevent sensitivity attenuation and maintain accuracy.
Electrochemical type:
For detecting low-concentration carbon monoxide in artificial gas and incomplete combustion processes, it is crucial to use an electrochemical gas sensor with high sensitivity and accuracy, considering the high toxicity of carbon monoxide. The alarm point for carbon monoxide typically does not exceed 200ppm, and using an electrochemical sensor helps prevent false alarms or missed detections.
Infrared type:
Infrared combustible gas sensors utilize the non-dispersive infrared (NDIR) principle to detect hydrocarbon combustible gases present in the air. They offer advantages such as good selectivity, strong interference resistance, resistance to poisoning, and infrequent recalibration. Infrared sensors have played a significant role in industrial safety and gas detection in recent decades.
