Expanding catalytic sensor capabilities to combustible gas mixtures monitoring

• Published in: Measurement : journal of the International Measurement Confederation Vol. 194; p. 111103
• Main Authors: Ivanov, I.I., Baranov, A.M., Spirjakin, D.N., Akbari, S., Mironov, S.M., Karami, H., B. Gharehpetian, G.
• Format: Journal Article
• Language: English
• Published: London Elsevier Ltd 15.05.2022; Elsevier Science Ltd
• Subjects: Assessments; Calibration; Catalytic sensor; Combustible gas mixtures; Data processing; Explosion hazard assessment; Flammability limits; Flammable gases; Gas mixtures; Gases; Hexanes; Mathematical analysis; Measurement errors; Sensors; Two-stage heating profile; Catalytic sensor; Combustible gas mixtures; Two-stage heating profile; Explosion hazard assessment
• ISSN: 0263-2241; 1873-412X; 1873-412X
• DOI: 10.1016/j.measurement.2022.111103

[Display omitted] •Approach for rapid assessment of the explosiveness of combustible gas mixtures is presented.•The technique is based on determining the amount of heat released during the gas combustion.•Two-stage heating pulse and an approach to the catalytic sensor calibration were developed.•The technique has been validated for various mixtures of methane, propane, butane and hexane. Preventing the explosion of mixtures of combustible gases and vapors is an important task in industry. This research presents an approach for rapid assessment of the explosiveness of combustible gas mixtures of unknown composition. The technique is based on registering the amount of heat released during the combustion of a portion of gases inside the catalytic sensor. The phenomenological theory of the approach for rapid assessment of the explosiveness was also presented. To carry out the measurements, a two-stage heating pulse and an approach to the calibration of the catalytic sensor were developed. The experiments were carried out for various mixtures of methane, propane, butane and hexane within the pre-explosive range (up to 50% Low Explosive Limit). In order to calculate the Lower Explosive Limit (LEL) of a mixture of flammable gases, Le Chatelier’s rule was used. Industrial catalytic sensors with additional diaphragm that limits the gas leakage into the sensor were used for measurements. The advanced data processing which is based on integrating the area under the measured dependence of sensor response on time was used to calculate the heat released. The parameters affecting the measurement results were analyzed. The measurement values were in good agreement with the prescribed values. The measurement errors did not exceed 10%. Since in this approach there is no need to identify gases, or their quantity and concentration, it can be used in industry for quick determination of potentially explosive mixtures in the air.