The invention discloses a method for producing
methanol, coproduct
hydrogen and byproduct steam by utilizing hydrocarbonaceous
tail gas. The invention is characterized in that the method includes the following steps: A, hydrocarbonaceous
tail gas is subject to self hydrogenation under the action of catalyst,
unsaturated hydrocarbon is converted into saturated
hydrocarbon, and meanwhile sulfocompound generates
sulphur compound which can be easily removed under the action of catalyst; and heat generated in the reaction is utilized to produce steam; B,
sulphur compound removal is carried out on the products obtained by the step A; C, the products obtained by the step B react with the steam to prepare
hydrogen,
carbon monoxide and
carbon dioxide under the action of catalyst; D, the products obtained by the step C are used for preparing
methane under the action of catalyst; E,
methane and
hydrogen are respectively collected. The invention has the beneficial effects that: resource is reasonably utilized,
energy conservation and emission reduction and
environmental protection can be realized; carbon element is converted into
methane, emission of
carbon dioxide is reduced, a desulphurization device is adopted to remove organic sulphur and inorganic sulphur in
tail gas,
sulphur compound emission is reduced, and the method is beneficial to
environmental protection. Waste is fully utilized and recycled, and industry chain is improved.