Method for producing high-efficiency methanol capable of reducing emission of carbon dioxide

A method for producing methanol, the method comprising:

• a first step of preparing mixed gas by using steam and natural gas as raw materials and converting C2+ hydrocarbons contained in the natural gas into methane over a catalyst;
• a second step of preparing a synthesis gas including carbon monoxide, carbon dioxide, and hydrogen by reforming the mixed gas in a reformer filled with a reforming catalyst;
• and
• a third step of a methanol synthesis process, in which methanol is prepared by using the synthesis gas as a raw material and reacting the synthesis gas in a methanol synthesis reactor filled with a methanol synthesis catalyst,
• wherein the methanol product in the methanol synthesis process and unreacted synthesis gas are separated, some of the separated unreacted synthesis gas is supplied to a heating furnace, providing reaction heat required for the reformer of the second step and combusted together with the natural gas, and the mixed gas supplied to the reformer passes through a heat exchanger while post-combustion gas emitted from the heating furnace passes through the heat exchanger to supply the mixed gas heated through heat exchange with the post-combustion gas in the heat exchanger to the reformer.