| 摘要 |
PURPOSE:To provide a reactor which solves the problems caused by the gas in the tube and the hot water in the methanol synthesis process at the same time, by applying a Cr-enriched layer having a specific thickness to the inner surface of a tube made of a low-alloy steel, and using the tube as the reaction tube filled with a catalyst. CONSTITUTION:The inner surface of a steel containing 0.4-0.7% Mo and 0.001-1.50% Cr is subjected to the chromizing treatment by powdery process, vapor process, etc. to apply a Cr-enriched layer containing >=16% Cr and having a thickness of 0.05-10mm to the inner surface, and the obtained reaction tube 5 is filled with granular solid catalyst 6. A mixed gas 1 containing hydrogen, carbon monoxide, and carbon dioxide and pressurized to 30-300kg/cm<2> is passed through the reaction tube 5, and made to contact with the catalyst 6 at 220-330 deg.C to produce methanol 10. Hot water 11 is supplied to he outer surface of the tube 5 to absorb the generated reaction heat, and the heat is recovered as saturated steam 4. The hydrogen corrosion of the inner surface with the mixed gas, the production of iron carbonyl, and the corrosion of the outer surface with hot gas can be solved at the same time by the use of the above double-walled tube. |
