Process for making catalyst inventory measurements and control procedure for adding or withdrawing catalyst
US5081039A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 1989 |
| Grant date | Jan 14, 1992 |
| Priority date | — |
| Expiry date | Nov 16, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T436/12
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The inventive procedure more accurately maintains an inventory of a catalyst in an ebullated bed of a reactor in an oil refinery, especially a resid hydrotreating unit. The ebullated catalyst bed has therein three phases (catalyst, oil, gas). A first density measurement is made of the two-phase mixture in a freeboard zone i.e. in a catalyst free area above the ebullated catalyst. A second density measurement is made in the catalyst bed where all three phases are present. Density measurements are used, along with values for vapor, liquid, and soaked particle densities and corrections for gamma-ray absorption coefficients, to calculate the catalyst particle holdup in the vessel. From this, the amount of catalyst actually in the reactor can be calculated. Once this amount is known, fresh catalyst may be added to or spent catalyst may be removed from the reactor in order to maintain a fixed catalyst inventory within the catalyst bed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.