Method of conducting an endothermic reaction in a packed-bed reactor with external energy addition

University of Kansas
posted on 10/03/2005

For solid-catalyzed exothermic reactions in packed-bed reactors, it has been established that periodic reverse flow operation can significantly reduce energy requirements as compared to conventional operation using unidirectional flow.

Suggested Uses

Besides using this technique for ethylbenzene dehydrogenation in a packed-bed reactor, the proposed flow reversal reactor operation can also be employed to maximize energy utilization in any packed-bed reactor operation that requires energy addition from external sources or preheating of the reactor feed.The proposed concept can also be intuitively extended for efficiently utilizing reactants that are added to reactors.

Detailed Description

For solid-catalyzed exothermic reactions in packed-bed reactors, it has been established that periodic reverse flow operation can significantly reduce energy requirements as compared to conventional operation using unidirectional flow. Periodic reverse flow operation efficiently traps the enthalypy of reaction in reactor bed which function as a regenerative heat exchanger subsequently provides fast reaction rates.

Scientists at the University of Kansas have developed an improved process for the conversion of enthylbenzene to stryrene employing a periodic reverse flow strategy. The average capacity of enthylbenzene dehydrogenation plants is over 100,000 metric tons per year. Hence, small improvement in plant operation efficiency can lead to relatively large returns. Our scientists� patented technology demonstrates that the proposed reverse flow strategy produces stationary state catalyst bed temperatures that are hundreds of degrees higher than the mixing temperature of the feed streams.

Furthermore, because of regenerative heat exchange in the reactor entry and exit regions, the average outlet temperature is hundreds of degrees lower as compared to conventional operation, resulting in a greater energy efficiency and providing desirable overall enthylbenzene conversion and stryrene selectivity.

File Number: 1993 FY 05

Web site: http://www.cpe.engr.ku.edu/

Other Information: *State of Development* Available for licensing.