The core technology of portable combustible gas detectors can be divided into two major camps: catalytic combustion and infrared optical. There are significant differences between the two in terms of principles, performance, applicable scenarios, and costs, which together build a protective net for industrial safety monitoring.
Catalytic combustion: classic technology, cost-effective choice
Catalytic combustion sensors detect gas concentration through changes in platinum wire resistance. When combustible gas burns flamelessly on the surface of platinum wire, the heat generated increases the resistance, and the output signal of the bridge is proportional to the gas concentration. Its core advantages lie in low cost, fast response (≤ 15 seconds), stable linear output, and broad-spectrum performance for most combustible gases such as methane and propane. For example, the catalytic combustion detector from Nanjing Aiyi Technology is widely used in the petrochemical industry. Through regular calibration (once every 3-6 months), it can maintain a detection accuracy of ± 3% and has a lifespan of 3-5 years. However, this technology relies on oxygen to participate in the reaction and is prone to failure in hypoxic environments such as closed storage tanks; At the same time, toxic gases such as sulfides and silicides can contaminate catalysts, leading to a decrease in sensitivity, and should be avoided in sulfur-containing chemical scenarios.
Infrared optical type: high-precision and cutting-edge representative, a powerful tool for complex environments
Infrared sensors are based on the absorption characteristics of gas molecules in specific infrared bands, and calculate concentration through light intensity attenuation. Its core advantages lie in the absence of oxygen, strong resistance to poisoning, long lifespan (over 5 years), and the ability to distinguish PPB grade trace gases. For example, Honeywell's infrared detector can accurately monitor gas (methane) underground in coal mines, maintaining an accuracy of ± 1% even in the presence of high concentrations of dust or sulfide interference. In addition, infrared technology supports multi gas synchronous detection. For example, the composite equipment of Nanjing Aiyi Technology can simultaneously monitor methane, carbon dioxide, and volatile organic compounds (VOCs), which is suitable for complex scenarios such as natural gas pipeline inspections. However, infrared sensors have high costs and strict requirements for light source stability, requiring regular cleaning of the optical window to avoid errors.
Technology selection: scene driven, precise matching
Catalytic combustion type: suitable for routine scenarios with limited budget and good environmental ventilation, such as small and medium-sized chemical plants and daily inspections of gas stations.
Infrared optical type: dominates high-risk and high complexity scenarios, such as oil and gas exploration, confined space operations, and high temperature and high humidity environments. Its anti-interference ability and long-term stability can significantly reduce accident rates.
The coexistence of two major technological camps reflects the upgrade of industrial safety monitoring from "passive alarm" to "active prevention". With the integration of the Internet of Things (IoT) and AI technology, future detectors will achieve remote monitoring, intelligent data analysis, and predictive maintenance, further strengthening security defenses.