Structural optimization calculation of methanol spiral tube reformer based on waste heat utilization and experimental verification of reactor performance

Spiral tube is compact, efficient in heat transfer and can make full use of the annular space in the engine, so it can be applied to heat recovery under a variety of operating conditions. This paper developed a three-rate, one-dimensional model combined with simulations, experiments. It can be found that in the hydrogen prediction, the model has an error of 10 % from experiment and 0.91 % from literature; the increase in length from 0.5 m to 1.35 m increases methanol conversion by 7.97 %; the increase in spiral diameter from 4 mm to 7 mm increases methanol conversion by 9.35%; spiral radius from 40 mm to 70 mm, methanol conversion rate decreased by 5%; mass fraction of methanol decreased by 16 % when the pitch was increased from 5 mm to 20 mm. When diameter is 4 mm, length is 1 m, the MSR reaction rate reach 24.1 mol/m³/s, methanol conversion rate is 87.91 %. When spiral pitch is 10 mm, spiral diameter is 40 mm, methanol conversion rate can reach 91.83 %. The spiral tube reactor has a compact structure and can achieve 87.19 % methanol conversion and 0.0955 L/min H₂ production at WHSV = 0.9 h⁻¹ and S/C = 1.7.