FIELD: chemistry.
SUBSTANCE: invention relates to two versions of the method of using dimethyl ether (DME) synthesis products to convert oxygenates to olefins. One of the versions comprises the following steps: extracting from a DME reactor a stream containing DME, water and methanol; separating, in a liquid-gas separator, carbon dioxide gas from the stream from the DME reactor to obtain a degassed output stream; feeding the degassed output stream into a DME column to obtain crude DME material and a solvent stream containing methanol and water; feeding the crude DME material into a reactor for converting oxygenates to olefins to obtain an olefin-containing output stream which also contains oxygenates; separating the olefin-containing output stream to obtain a fraction containing light olefins and a fraction containing heavy olefins, wherein the fraction containing light olefins contains ethylene and the fraction containing heavy olefins contains C4+; bringing the fraction containing light olefins into contact with a first portion of a solvent stream in a first zone of reacting with solvent to obtain a first olefin-containing purified stream and a first oxygenate-containing extract; bringing the fraction containing heavy olefins into contact with a second portion of the solvent stream in a second zone for reacting with solvent to obtain a second olefin-containing purified stream and a second oxygenate-containing extract.
EFFECT: disclosed method enables integration of dimethyl ether synthesis with conversion of oxygenates to olefins.
8 cl, 1 dwg
