Investigation of the effects of hydrogen and natural gas mixtures in different ratios on combustion emissions in a residential cooktop burner

This study aims to propose an alternative energy solution to mitigate the environmental impacts of fossil fuel usage by investigating the combustion emission characteristics of hydrogen-naturalgas mixtures. Hydrogen emerges as a promising environmentally friendly fuel candidate due to its carbon-free composition. In this context, various naturalgas-hydrogen mixtures with hydrogen ratios ranging from 0% to 30% were prepared, and combustion analyses were performed under laboratory conditions. The experiments were conducted using aresidential cooktop burner, where the gas mixtures were precisely regulated by mass flow-controlled (MFC) systems. Emissions, generated during the combustion process were measured using a flue gas analyzer. Additionally, atmospheric pressure and relative humidity in the experimental environment were continuously monitored with a BME280 sensor, while ambient temperatures were recorded using DS18B20 temperature sensors. The collected data were transmitted to a computer via an Arduino Uno control board, enabling real-time monitoring and recording through a Python-based interface. The study observed a general decrease in CO emissions as the hydrogen ratio increased from 0% to 15%. This can be attributed to hydrogen enabling cleaner combustion, thereby limiting carbon-based combustion products. However, at hydrogen ratios exceeding 15%, an upward trend in CO emissions was noted. While carbon dioxide (CO₂), nitrogen monoxide (NO), and nitrogen oxides (NOₓ) emissions generally decreased, there was a significant increase in nitrogen dioxide (NO₂) emissions. Additionally, higher hydrogen ratios led to a reduction in net efficiency values, whereas lambda values and oxygen content in the flue gas increased. The dew point temperature generally exhibited a decreasing trend, while the flue gas temperature fluctuated.