Effect of steam on heavy oil catalytic pyrolysis

Abstract

This paper studied the influence of steam on heavy oil catalytic pyrolysis. Experiments of Chinese Daqing atmospheric residue catalytic pyrolysis on CEP-1 were conducted in a confined fluidized bed reactor, with steam and nitrogen being used as the fluidizing gas, respectively. The effects of steam on the volume of contents of the components in pyrolysis gas, product yields, and carbon dioxide formation were discussed. The results of contrast tests showed that steam not only had the action of the fluidizing gas and the dilution gas, but also participated in steam gasification and water-gas shift reactions. In catalytic pyrolysis processes, steam could maintain the activity of catalysts, accelerate the reactions of carbonium ions, inhibit undesired secondary reactions, and enhance the yields and selectivity of the aimed products.