The Effect of Water Content on the Combustion Characteristics of Methanol in the Oxy-fuel System

The methanol economy is defined as using methanol as a means of energy carrier. It has been well known that methanol can be produced from waste and biomass or recycled carbon dioxide and water through the catalytic reaction. In a pure oxy-fuel combustion system, the oxidant stream contains only oxygen and carbon dioxide. After the fuel is burned, carbon dioxide and water are the main products. The carbon dioxide in the oxidant stream can be recycled and processed to reduce it to methanol. However, water is produced in the process of making methanol. Moreover, due to methanol's hydrophilic nature; hence, additional energy is required to remove the water from the methanol mixture. In the present study, the effect of water content on the spray combustion characteristics of methanol in the oxy-fuel system is experimentally studied. In the present study, the flame stabilization and the effect of flow rate were observed and characterized. The relationship between the oxygen content in the oxidizer stream and the moisture tolerance's upper limit in the methanol mixture was explored. For combustion efficiency, it can be estimated according to the emission index of CO (EICO). The effect of water content in methanol on flame stabilization, emissions, and relative efficiency is also evaluated. This research provides several important conclusions related to the methanol spray combustion in the oxy-fuel combustion system. Understanding the spray combustion of methanol and its stabilization, emissions, and relative efficiency will serve as the basis for the further high-efficiency application.