IPE-TM-300 Vessels
Spherical Reactors
IPE-TM-300-10
1. Purpose
This procedure provides revamp guidelines for the mechanical design of existing spherical reactors.
2. General
Follow these guidelines when revamping an existing spherical reactor. Inflection Point Engineering does not design new spherical reactors.
- Spherical Reactor Criteria
The following criteria is based on a study that compared spherical reactors that performed as expected versus spherical reactors that did not perform as expected. The reactors which performed well met the criteria below. The reactors which performed poorly did not meet the criteria below.
- L/D shall not be less than 0.3 and shall not exceed 0.426. “L” is the catalyst bed height. “D” is the spherical reactor diameter.
- Catalyst Volume < 60% of the total reactor volume
- Catalyst bed must be centered in the reactor.
- Follow Procedure for normal layers and heights of inert ceramic balls. If necessary, adjust ICB layers below catalyst bed to satisfy criterion 3.c.
- Use a single phase vapor inlet distributor.
- Use an outlet basket per Inflection Point Engineering Standard Drawing 3-328 (“Outlet Basket”).
- Maximum vapor velocity exiting the inlet diffuser shall be 45 ft/sec.
- Minimum distance between the top of the inert ceramic balls and the bottom of the inlet distributor shall be 1’-6”. If this criterion cannot be met, then perform a calculation to ensure the top layer of inert ceramic balls is not disturbed by the incoming vapor (see Appendix 2 of ).
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© 2026 Inflection Point Engineering, LLC. All rights reserved.