| 摘要 |
In the cracking of liquid and/or gaseous hydrocarbons in the presence of fluidized granular inert or carbonaceous solids at 650-850 DEG C. to produce gaseous olefins, e.g. ethylene, the effluent containing entrained solid is passed through a cyclone to remove the bulk of such solid and is then contacted with a hydrocarbon oil boiling above 250 DEG C. which is a recycled portion of the product and which quenches the effluent and thereby vaporizing the lower boiling fraction of the recycled oil and removes the remaining entrained solid in the unvaporized higher boiling fraction, such solid is at least partly removed from the quenching oil and the oil is recycled to the fluidized bed reactor. Oxygen and/or steam may be added to the reaction, and pressures of 1.2-1.5 atmospheres are preferred. The solid used is oil coke, ceramic, corundum, sillimanite or sand. The process removes fine-grained solids from the reactor and thereby maintains at least 50%, preferably 70-95%, of the solid within the desired grain size of 100-3000 microns. The quenching oil preferably boils in the range 350-650 DEG C. and, in quenching, a lower boiling oil may be added to assist cooling by evaporation. Solids are removed from the oil by centrifuging to separate 30-100% before recycle. |
