Wet gas scrubbing: State of the art in FCCU emission control

✍ Scribed by Cunic, J. D. ;Bienstock, M. G. ;Edelman, A. M.

• Publisher: American Institute of Chemical Engineers
• Year: 1987
• Tongue: English
• Weight: 734 KB
• Volume: 6
• Category: Article
• ISSN: 0278-4491
• DOI: 10.1002/ep.670060414

✦ Synopsis

flue gas can be controlled via wet gas scrubbing. Wet Gas Scrubbers (WGS) are compatible with the gaseous emission control devices such as CO boilers or High Temperature Regeneration (HTR) now in use on FCCU's and require no changes in FCCU operating procedures. Compared with a combination of particulate control with electrostatic precipitators and SO2 control b y FCCU feed desulfurization, WGS require less investment and have lower operating costs. Other advantages for WGS include higher service factor, smaller onsite plot space requirement, and simpler operation than electrostatic precipitators. Purged scrubber liquid must be treated b y conventional waste water treatment technology to reduce suspended solids and COD. Even after such treatment, the purge stream will still contain dissolved solids. However, at many locations, the disposal of the purge stream can be accommodated without adverse environmental problems. Four commercial scrubbers, now in operation in Exxon Company, U . S. A. refineries, reduce particulate emissions to compliance levels with all pertinent regulations. SO2 removals are in excess of 90%.

Currently, four licensee companies are also applying the Exxon scrubbing process. More are anticipated. These commercial units have accumulated over 64 years of combined operations (as of February 1, 1987).

Particulates and SO2 in Fluid Catalytic Cracking Unit (FCCU)