Dreistufenverfahren zur Herstellung von leichten Olefinin aus rauhe Methan und/oder Ethan

摘要

Light olefins (72, 74, 76) are produced from a hydrocarbon gas stream (50) by a combination of steam reforming (54), oxygenate production (58), and oxygenate conversion (66) to olefin wherein a crude methanol steam (60) - produced in the production of oxygenates and comprising methanol, light ends, and heavier alcohols - is passed directly to the oxygenate conversion zone (66) for the production of light olefins. Furthermore, the combination provides the synergy for increased catalyst life and reduced water treatment costs by recycling by-product water (71) produced in the oxygenate conversion zone to provide water to the steam reforming zone (54). The advantage of this integration is the elimination of costly methanol separation and purification steps which result in the overall reduction in the costs of producing the light olefins. In addition, a portion of the by-product water can be combined with a propylene stream to provide a high octane blending component for gasoline. The propylene and butylene fractions produced by the above integrated scheme are further converted to high octane ether and other high value products.