ABSTRACT
The commercial fixed-bed methanol-to-gasoline (MTG) unit, a 14,500 barrel per day gasoline unit, was erected in New Zealand to convert natural gas to gasoline via methanol synthesis. The fluid-bed unit operates at much lower pressures than the fixed-bed unit, and its yield pattern is different, having lower liquid yield and higher light olefins than yield of fixed-bed units. Instead of producing an aromatic gasoline, methanol can also be converted to yield mostly light olefins. The hydrocarbons are separated into light olefins, an ethene-rich stream and an aromatic gasoline stream, which is blended into the final gasoline product. The light olefins are fed to the Mobil’s Olefins-to-Gasoline and Distillate (MOGD) unit along with an MOGD recycle stream. The process combines the slurry-phase Fischer-Tropsch synthesis technology with a fixed-bed ZSM-5 reactor, which converts the vapor phase product from the first-stage reactor to high quality gasoline.
