Patent · US Expired

Standpipe inlet enhancing particulate solids circulation for petrochemical and other processes

US6228328A · kind A · utility

0Cited by
16References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 22, 1999
Grant dateMay 8, 2001
Priority date
Expiry dateFeb 22, 2019

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB01J2208/00769
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

In a fluid catalytic cracking (FCC) unit, a regenerator or a stripper includes a standpipe for circulating catalyst from one vessel to another, the standpipe having an inlet design which reduces gas entrainment during catalyst transport by partial de-fluidization in the standpipe inlet region. The standpipe inlet design could include multiple inlet openings through the top of the standpipe or from the side wall by means of slots, or both, and a horizontal disk surrounding the standpipe below the slots for blocking the upward flow of bubbles, the combination thereby forming a dense fluidization zone above the disk and surrounding the inlet, including the slots. Additionally, the disk may include a downwardly-projecting lip or edge forming an inverted void space around the standpipe and the downwardly-projecting edge may further include vent holes around its circumference which allow bubbles trapped under the disk to be vented outside the standpipe inlet region. Above and below the disk and surrounding the standpipe, gas injection rings may be used to prevent the dense fluidization zone above the disk from complete de-fluidization, thus assisting the catalyst to remain fluidized and …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.