METHOD AND APPARATUS FOR HOMOGENEOUS OXIDATION OF METHANE-CONTAINING GAS Russian patent published in 2011 - IPC C07C27/00 C07C31/00 C07C47/04 

FIELD: chemistry.

SUBSTANCE: invention relates to a method for homogeneous oxidation of a methane-containing gas, involving feeding into the cycle a methane-containing gas preheated to 430-450°C in at least three series-arranged oxidation reactors made from carbon steel. Each of the reactors, except the last, is separately connected to exhaust-heat boilers. Oxygen is also fed into the reactors in such an amount that a mixture forms outside the explosive range, which causes homogeneous oxidation of the methane-containing gas while simultaneously raising temperature of the gas mixture to 540-560°C. Subsequent quenching-cooling of the gas mixture is carried out in exhaust-heat boilers to temperature 440-450°C by feeding water into the exhaust-heat boilers where vapour is formed, which is fed into fractionation columns for separating end products. Further, the reaction mixture from the last reactor which is not connected to an exhaust-heat boiler enters a separator. On he way to the separator, the reaction mixture heats the gas and some of its heat is used to obtain water vapour, which is mixed with vapour from the heat-exchange boilers. From the separator, the liquid phase enters the fractionation step where methanol rectificate is obtained, as well as ethyl alcohol and formaldehyde. The gaseous phase goes absorbers for removal of SO₂, CO and CO₂. In the first absorber, the gaseous phase is purified from SO₂ and from CO and CO₂ in the second absorber, followed by extraction of said gases from the absorption solution of the second absorber in a desorber. Liquid phase outlets of the absorbers are connected to collectors to facilitate reclamation of absorbing solutions with separation and outlet of CO and CO₂ fractions from the desorber. Outlets of the collectors are connected to inlets of the absorbers for feeding the formed solutions for removing SO₂, CO and CO₂ from the gas. While cleaning the gas phase, the circulation cycle is partially blown in order to remove inert gases, for example nitrogen and argon entering the cycle together with the methane-containing gas and oxygen. The number of blows is determined by the amount of inert gases available in the cycle. After purification and blowing, the cycle is closed by injecting the gaseous phase which consists of methane-containing gas and gas from the second absorber. The invention also relates to apparatus for homogeneous oxidation of methane-containing material.

EFFECT: high efficiency during operation and high output of the obtained product, as well as high environmental friendliness.

2 cl, 1 tbl, 1 dwg