PROCESS FOR PREPARING OLEFINS FROM HEAVY PETROLEUM OIL

摘要

Preparing olefins by mixing heavy petroleum oil (i.e. crude oil and atmospheric pressure and reduced pressure residual oils) with superheated steam in an atomizer (5) with a steam-oil ratio of from 2 to 7, and feeding the resulting mixture into an indirectly heated reaction tube (6) so that the temperature at the outlet (8) of the reaction zone is from 700 to 950 DEG C. The residence time of the mixture in the reaction zone is from 0.01 to 0.1 second. Olefin yields resulting from thermal cracking are high, and deposition of carbonaceous substances and development of coking on the inner wall of the reaction tube are substantially avoided.