Research on Detection Equipment for Non-Methane Total Hydrocarbon Purification Efficiency in Oil-Smoke Purification Devices

This study focuses on developing a method to evaluate the purification capacity of cooking fume purification equipment for non-methane total hydrocarbons (NMTHC) in a laboratory setting, aiming to enhance the scientificity and accuracy of the assessment process. A novel generating device capable of stably producing high concentrations of NMTHC has been developed. Suitable detection methods for NMTHC in cooking fumes were identified, and a laboratory test platform was established for evaluating the purification effect of NMTHC. The performance of the soot generator, capable of consistently producing NMTHC concentrations up to 40-50 mg/m³ with repeatability below 15%, was developed, overcoming the challenge of simulating high NMTHC concentrations emitted in the catering industry. Two detection methods, a portable hydrogen flame ionization detector and gas chromatography, were compared experimentally. Integrating the selected detection methods with the newly developed NMTHC generator and a laboratory standard bench, a testing platform was constructed to evaluate the efficiency of cooking fume purification equipment in handling NMTHC. Experimental verification of this platform demonstrated stable performance for both high and low concentrations of NMTHC, with repeatability below 15% and 20% respectively. The findings indicate that the developed detection system can reliably and effectively evaluate the performance of catering industry fume purification equipment in treating NMTHC, laying a foundation for standardized laboratory testing.