Method for preparing methanol synthesis gas with oven gas and blast furnace gas

Abstract

The invention discloses a preparation method for methanol synthetic gas through coke oven gas and blast furnace gas. The preparation method adopts coke oven gas as the raw material, and H2 is extracted through pressure swing adsorption; the blast furnace gas with high yield and relatively low calorific value is adopted as the raw material, an adsorbent which can adsorb CO and CO2 is utilized to simultaneously extract and reclaim the CO and the CO2 in the blast furnace gas, and then the H2, the CO and the CO2 are mixed and prepared into the methanol synthetic gas. The hydrogencarbon ratio f value of the methanol synthetic gas prepared according to the method is within the optimum range of 2.05 to 2.60, and the contents of nitrogen gas and other impure gases are suitable for the methanol production. The by-product gas generated during the steel production process is utilized to prepare the methanol synthetic gas, the useful components in the gas are utilized, the discharging of harmful substances into the environment is reduced, and not only the chemical reaction can not occur during the process, but also the carbon adding is not required, the technical process is short, the process is simple, and the cost is low, so the preparation method is one of the preferable methods for the preparation of methanol synthetic gas.

Description

technical field [0001] The invention relates to a method for producing methanol synthesis gas, more specifically, relates to a method for producing methanol synthesis gas with coke oven gas and blast furnace gas. Background technique [0002] Coke oven gas, blast furnace gas and converter gas are by-products in the iron and steel production process. At present, only part of the heat energy is recovered, and their effective components have not been utilized efficiently. The coke oven gas, blast furnace gas and converter gas produced in the iron and steel production process are rich in hydrogen, carbon and other elements, and useful components are recovered from them to prepare methanol synthesis gas and produce methanol. The production cost is low and has good economic benefits. It is an effective way to use it. Coke oven gas contains hydrogen (H 2 ) is high, contains low carbon monoxide (CO), and the hydrogen-to-carbon ratio f value reaches about 6 {f=(H 2 -CO 2 ) / CO+CO ...

AI Technical Summary

Problems solved by technology

Among them, the CO content and calorific value of converter gas are higher than those of blast furnace gas, so it is a better source of carbon elements in methanol synthesis gas. Methanol process; but the output of converter gas is small, not enough for methanol production and carbon replenishment, and the pressure and composition of converter gas fluctuate greatly, so converter gas is generally only used for heating by the enterprise itself

Blast furnace gas has a large output, which can be used for carbon supplementation in methanol production, but its CO content and calorific value are low, and its inert gas content is high, making recovery difficult

At present, pressure swing adsorption is mainly used to recover CO from blast furnace gas. For example, Xie Guangquan (Natural Gas Chemical Industry, No. 6, 1995) proposed to use blast furnace gas to first desulfurize and remove CO with MDEA 2 After that, CO is extracted by pressure swing adsorption, CO is compressed, partially transformed, and CO is removed by MDEA 2 , After fine desulfurization, with the purge gas PSA-H 2 H from the device 2 A method for obtaining methanol synthesis gas after mixing; Chinese patent (CN1100588C, 1997.10.24) proposed a two-stage pressure swing adsorption technology for separating and concentrating CO from blast furnace gas. The first stage removes strong adsorption components such as carbon dioxide, and the second stage obtains CO fuel gas is designed to solve the problem of extracting CO as fuel from blast furnace gas; another CO in blast furnace gas can be used as a carbon source for methanol synthesis gas 2 It is discharged as exhaust gas, which not only affects the environment, but also wastes resources.

Images