Mitigation of top of catalyst bed fouling

Abstract

This invention relates to reactors with mitigation of fouling-related pressure buildup, the reactors having a reactor bed containing at least one catalyst layer through which reactants flow. The mitigation of fouling which occurs at the top of the reactor bed is accomplished by using at least one blowback ring located near the top of the reactor bed.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This is a Divisional Application under 37 C.F.R. §1.53(b) of U.S. Ser. No. 11 / 047,865 filed Feb. 1, 2005 which claims the benefit of U.S. Provisional Application U.S. Ser. No. 60 / 557,487 filed Mar. 30, 2004.FIELD OF THE INVENTION[0002]This invention relates to reactors having a reactor bed containing at least one catalyst layer through which reactants flow. More particularly, it relates to the mitigation of fouling which occurs at the top of the reactor bed by using at least one blowback ring located near the top of the reactor bed.BACKGROUND OF THE INVENTION[0003]Reactors containing fixed catalyst beds typically experience pressure drop buildup due to catalyst fouling, particularly at the top of the catalyst bed. There are devices and reactor internals in use to mitigate top of the bed fouling, including bypass tubes, bed grading, scale baskets and scale traps. Top of the bed fouling can lead to high pressure drops which in turn can lead ...

AI Technical Summary

Benefits of technology

This patent describes a reactor that reduces the buildup of materials on the surface of the reactor vessel and the catalyst particles inside it. This is accomplished by using a top layer of inert or catalytically active material, with a blowback ring embedded in it that contains jets for directing fluid jets upward. This allows for the removal of foulants that accumulate on the surface of the reactor without disturbing the underlying catalyst bed. The use of blowback rings helps to prevent pressure drop buildup and reduces the need for reactor shutdowns, resulting in increased production efficiency.

Problems solved by technology

Reactors containing fixed catalyst beds typically experience pressure drop buildup due to catalyst fouling, particularly at the top of the catalyst bed.

Top of the bed fouling can lead to high pressure drops which in turn can lead to premature shutdown of the reactor.

This practice is expensive because bed skimming necessitates reactor shutdown for a prolonged period of time.

However, there are several inherent risks of using periodic backward or backwash flow.

The upward backwash flow can lead to lifting of the catalyst bed and fluidization of the catalyst particles.

Bed lifting and fluidization can lead to breakage and deterioration of the catalyst particles in the bed.

More importantly, the upflow can disrupt the integrity of the catalyst bed as the bed may not settle out uniformly after the upflow is ceased and the normal downflow is restarted.

This will lead to flow channeling, non-uniform contacting with the catalyst, and hot spots.

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