FCC Flue Gas Filtration

Apart from the many challenges that refiners are confronted with, they also have to face new stringent regulations with regard to, amongst others, FCC catalyst fines emissions. Royal Dahlman offers Best Available Technology (BAT) for the reduction of particulate matter (PM) emissions. Our innovative and highly efficient, proven filtration technology, guarantees the lowest catalyst fines emissions, at low installed costs, compared to other separation technologies such as an Electrostatic Precipitator (ESP), a Third Stage Separator (TSS) or a Wet Scrubber (WGS). 

Downstream of the WHB: Full Flow FCC Flue Gas Filter Packages (Full Barrier Filters):

When there is no need to protect equipment upstream of the Waste Heat Boiler (WHB) such as a Power Recovery Unit, the Refiner can decide to install an ESP, a Wet Gas Scrubber or a Full Flow (Full Barrier) Filter downstream of the Waste Heat Boiler. Royal Dahlman has developed the latter based on an extensive experience in refining processes and know-how of proven FCC flue gas filtration technology.

We are proud that we can offer an economic, safe and reliable long-term solution to face the current, and not less important, future environmental and governmental emission regulations. The benefits of a Full Flow FCC Flue Gas Filter Package compared to an ESP, TSS or WGS are impressive:

• no risk on explosions (as with an ESP)
• lowest, guaranteed emission << 10 mg/Nm3
• low OPEX & CAPEX (as with an ESP, TSS or WGS)
• no sensitivity to (sudden) solids load changes (as with an ESP or TSS)
• small plot space (as with an ESP or WGS)
• dry solids disposal, no need for further processing (as with a WGS)
• no visible plume (as with a WGS)

Upstream of the WHB: High Temperature FCC Flue Gas Filters:

In some refineries the installation of a full flow filtration system, or a combined separation/filtration system, upstream of the Waste Heat Boiler may be considered. Royal Dahlman’s High Temperature FCC Flue Gas Filters can offer a solution for this duty. This can be a Fourth Stage Filter, or Underflow Filter, supporting a Third Stage Separator (TSS) to reduce the overall catalyst fines emission, or a Full Flow(Full Barrier) Third Stage Filter system, replacing the Third Stage Separator & Underflow Filter.

With a Third Stage Filter Package an excellent catalyst fines emission reduction can be achieved, although it should be mentioned that the design of a Full Flow (Full Barrier) FCC Flue Gas Filter designed for a high temperature and pressure, often requires multiple pressure vessels resulting in an increased plot space and significantly higher CAPEX.

For both duties Royal Dahlman offers a unique, proven hot gas FCC Flue Gas Filter design featuring a ‘downflow’ arrangement and special gas distribution inlet section, developed based on extensive CFD analyses and tailored for the filtration of hot FCC flue gas. Our High Temperature FCC Flue Gas Filters utilizes high quality, sintered porous metal filter elements, that have demonstrated an excellent performance under the severe FCC flue gas conditions. 

Main features & benefits:

• Low operational risk & OPEX:
  - proprietary 'downflow' filter design to minimize wear and tear
  - proprietary gas inlet distribution section to reduce internal velocities and to increase filter element lifetime
  - porous sintered metal technology for low pressure drops & excellent in-situ cleaning 

• High reliability and availability (> 1 TAR):
  - special alloy filter media with proven performance in a FCC flue gas environment 

• Enhanced operational safety & reliability:
  - design for upset conditions (maximum solids load)