To produce dimethyl ether (DME) from methanol using Toyo Engineering Corp.’s (TOYO’s) DME synthesis technology based on a methanol dehydration process. Feedstock can be crude methanol as well as refined methanol.
If feed is crude methanol, water is separated out in the methanol column (1). The treated feed methanol is sent to a DME Reactor (2) after vaporization in (3). The synthesis pressure is 1 MPaG–2 MPaG. The inlet temperature is 220°C–275°C, and the outlet temperature is 300°C–375°C. This process is a one-pass conversion from methanol to DME. DME reactor yields are 70%–80%. The reactor effluents DME with byproduct water and unconverted methanol are fed to a DME column (4) after heat recovery and cooling.
In the DME column (4), DME is separated from the top and condensed. The DME is cooled in a chilling unit (5) and stored in a DME tank (6) as a bulk product.
Water and methanol are discharged from the bottom and fed to a methanol column (1) for methanol recovery. The purified methanol from this column is recycled to the reactor after mixing with feedstock methanol.
Economics: The methanol consumption for DME production is approximately 1.4 ton of methanol per ton of DME.
Licensor: Toyo Engineering Corp. (TOYO)