A comparative study and investigation of the combustion characteristics of ethanol replacing diesel fuel in industrial boilers.

According to a report from the Ministry of Industry, over 8,800 steam boilers are used in the country as a source of heat for the production process, producing over 109,000 tons of steam per hour. Most of the fuels used are fossil fuels that contribute to global warming due to large amounts of greenhouse gas emissions. In 2021, the industrial sector contributed to more than 76.5 million tons of carbon dioxide (CO₂) emissions, accounting for 31% of the country's total CO2 emissions. Pursuing renewable or renewable energy that reduces greenhouse gas emissions and is sustainable, is another crucial factor that will lead the country toward the goal of being carbon neutral by 2050. 

            Currently, the boiler system primarily relies on liquid fuels, such as fuel oil and diesel, due to their low cost and higher combustion efficiency compared to solid fuels. Ethanol, a renewable liquid fuel derived from crops, has a domestic production capacity of 3.12 billion liters per year, but the current production stands at 1.58 billion liters annually due to lower demand. Ethanol shows significant potential as an alternative fuel to replace fossil fuels in boiler systems. However, it has distinct thermal and physical properties that require a comprehensive study, especially regarding combustion efficiency for industrial applications.

            Preliminary assessments indicate that if even 1 percent of the country's industrial boilers switch to ethanol from diesel or fuel oil, it could reduce CO₂ emissions by 18.6 thousand tons annually. Moreover, larger boilers using higher proportions of ethanol would further enhance CO₂ reduction and promote the adoption of clean energy from ethanol. As the world trends towards electric vehicles, the future demand for transportation fuel may decrease.

            This research will focus on studying the variables of fuel pressure, excess air volume, and nozzle size, which impact temperature within the combustion chamber and the concentration of exhaust gases (CO, CO₂, O₂, and HC), by comparing results between diesel and ethanol.