Process and apparatus for reacting feed with a fluidized catalyst with a reduction in catalyst loss during startup

Patent metadata

Field	Value
Publication number	US-12453966-B2
Application number	US-202117565857-A
Country	US
Kind code	B2
Filing date	Dec 30, 2021
Priority date	Dec 30, 2021
Publication date	Oct 28, 2025
Grant date	Oct 28, 2025

Abstract

A fluidized catalytic reactor connected to a start-up heater is provided. The start-up heater provides sufficient heat to a catalyst containing stream to gradually increase the feed temperature. This allows for a critical volumetric flow rate to be achieved so that catalyst can be recovered from product instead of being entrained in product.

First claim

The invention claimed is:

1. A reactor system comprising:
a. a reactor for contacting a reactant stream with a catalyst;
b. a start-up heater having lines for the reactant stream to be sent to said reactor; and
c. a valve configured to receive a stream obtained from a feed-effluent heat exchanger,
wherein said start-up heater provides sufficient heat to fluidize said catalyst sufficiently to allow for at least a 3 ft/sec superficial gas velocity in said reactor.

2. The reactor system of claim 1 wherein said start-up heater is located downstream from said feed-effluent heat exchanger.

3. The reactor system of claim 1 wherein said start-up heater is upstream from said reactor.

4. The reactor system of claim 1 wherein the start-up heater is a fired heater, heat exchanger or a hot oil heater.

5. A process of start-up of a reactor comprising circulating a portion of a feed through a start-up heater to heat said feed to a temperature of at least 240° C. before a heated catalyst feed is sent from a regeneration unit to said reactor,
wherein said start-up heater provides sufficient heat to fluidize said heated catalyst feed sufficiently to allow for at least a 3 ft/sec superficial gas velocity in said reactor.

6. The process of claim 5 wherein said feed is at a volumetric flow rate at least 85% of a design flow rate for said reactor.

7. The process of claim 5 wherein said start-up heater heats a reactor feed stream until an exit temperature from said reactor for a feed effluent exceeds a predetermined temperature.

8. The process of claim 5 wherein said start-up heater provides sufficient heat to fluidize said heated catalyst feed sufficiently to allow for at least a 5 ft/sec superficial gas velocity in said reactor.

9. The process of claim 5 wherein said reactor is a fluidized bed paraffin dehydrogenation reactor.

10. The process of claim 5 wherein said heater is a fired heater, heat exchanger or a hot oil heater.

11. The process of claim 5 wherein said feed is at a volumetric flow rate at least 50% of a design flow rate for said reactor.

Assignees

• Uop Llc

Inventors

• Johnson Ii Richard A
• Senetar John J
• Kulprathipanja Sathit
• Kanyuh Adam J

Classifications

• C07C5/333

  Catalytic processes · CPC title

• B01J2208/00168

  with heat exchange elements outside the bed of solid particles · CPC title

• B01J2208/00548

  Flow · CPC title

• B01J2208/00504

  by means of a burner · CPC title

• B01J8/24

  according to "fluidised-bed" technique (B01J8/20 takes precedence) · CPC title