Turbulent/fast fluidized bed reactor with baffle for maximizing low-carbon olefin yield

Abstract

Systems and methods for producing low carbon olefins in which a feed stream comprising naphtha is flowed into a reaction unit comprising a fast fluidized bed reactor connected to and in fluid communication with a riser reactor. The fast fluidized bed reactor includes baffles therein to minimize backmixing therein to maximize the production of low carbon olefins. The effluent of the fast fluidized bed reactor further flows into the riser reactor. A lift gas, which may include nitrogen, methane, flue gas, or a combination thereof, is injected through an injector into the combined reaction. The effluent from the riser reactor is separated in a product separation unit to produce a product stream comprising the low carbon olefins and the spent catalyst. The spent catalyst is further stripped with a stripping gas comprising methane, nitrogen, flue gas, or a combination thereof. The stripped spent catalyst is regenerated to produce a regenerated catalyst, which is then flowed to a fast fluidized bed reactor.

Description

[0001] Cross References to Related Applications [0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 883,072, filed August 5, 2019, which is incorporated herein by reference in its entirety. technical field [0003] The present invention generally relates to a process for the production of olefins. More specifically, the present invention relates to an integrated process involving the catalytic cracking of naphtha in a fast fluidized bed connected to a riser reactor for the production of olefins. Background technique [0004] Low carbon olefins (C 2 to C 4 Alkenes) are the synthetic building blocks of many chemical processes. Light olefins are used in the production of polyethylene, polypropylene, ethylene oxide, vinyl chloride, propylene oxide and acrylic acid, which in turn are used in a variety of industries including plastics processing, construction, textiles and the automotive industry. Typically, light olefins are produced by ste...

AI Technical Summary

Problems solved by technology

However, the yield of light olefins may be relatively low due to backmixing in the fluidized bed reactor

In addition, conventional fluidized bed reactors for catalytic cracking typically operate with low average solid volume fractions and low gas-solid contact efficiencies due to the limitation of superficial gas velocity in the fluidized bed

Therefore, conventional methods often result in the formation of large amounts of methane due to thermal cracking and increased production costs of light olefins

Images