Investigations into the Evaporation Efficiency and Hydrogen Production Rate of Methanol-Water Fuels in a Steam Reformer Tube

The present study considers a tubular reformer packed with CuO/ZnO/Al2O3 catalyst and heater tubes. Five different fuels are considered, namely four methanol-water fuels with molar ratios of 40%:60%, 50%:50%, 62%:38%, 75%:25%, and pure methanol fuel. For the methanol-water fuels with methanol molar fractions of 40, 50 and 62%, respectively, the temperature reaches a minimum value after approximately 0.22 m. Furthermore, the methanol mass fraction conversion rate exceeds 98%. The hydrogen mass fraction increases with an increasing methanol molar fraction and has a value of approximately 13.43% given an input fuel with a methanol molar ratio of 62%:38%. For the fuels with methanol molar fractions of 75 and 100%, respectively, the methanol mass conversation rate reduces to around 66.57 and 22.72%, respectively. As a result, the hydrogen mass fraction has values of just 6.85 and 1.42%, respectively. In other words, for the inlet temperature, velocity and pressure conditions considered, the reaction efficiency is degraded for methanol-water fuels with higher methanol content, and hence the hydrogen production efficiency is reducing.