May-2022

Carbon Footprint Reduction of FCC

In a typical fluid catalytic cracking (FCC) based refinery, around 20-30% (IHS Markit, 2021), (Carbon Capture Project, 2013), (WoodMckenzie, 2021) of the total Scope 1 and 2 emissions originate from the FCC unit.

Jan De Ren
Honeywell UOP

Article Summary

In a typical fluid catalytic cracking (FCC) based refinery, around 20-30% (IHS Markit, 2021), (Carbon Capture Project, 2013), (WoodMckenzie, 2021) of the total Scope 1 and 2 emissions originate from the FCC unit. Most of those emissions, approximately 70%, come from the flue gas as a result of coke burn operation to satisfy the unit heat balance and regenerate the catalyst (UOP, 2021). From a carbon footprint reduction perspective, this presents an excellent opportunity for refiners to significantly reduce their footprint by doing carbon capture on a single point source. The remaining emissions come from utility requirements, which can be significantly reduced via intelligent process and equipment design tailored towards increased energy efficiency, optimised heat integration, and minimised hydraulic requirements.

A key enabler for market adoption of CO2 capture on FCC flue gas will be a differentiated technology that provides the lowest cost of CO2 capture. Financial incentives like the EU Emissions Trading System, 45Q US federal tax credits and state-level incentives such as California’s Low Carbon Fuel Standard boost the bankability of these projects. However, a state-of-the-art, low Capex, and ready now technology solution is still required to make these projects bankable.

To address this challenge, Honeywell UOP, in collaboration with the University of Texas, is offering the Advanced Solvent Carbon Capture technology (ASCC), which uses a combination of a proprietary solvent, high-efficiency column internals, and a novel heat exchanger system resulting in several features:

• The ability to regenerate the solvent using low-level heat (LP steam rather than MP)
• High mass transfer solvent that enables higher pressure stripper operation for greater solvent stability and lower consumption
• High mass transfer stripper internals that enable faster regeneration in a smaller column
• Optimised heat integration via a novel heat exchanger system

These features result in reduced Capex and Opex, which translates into 10-15 $/tonne lower cost of captured CO2 compared to prior generation solvents (UOP, 2022). It is a ready[1]now technology that has been extensively tested and validated at the US National Carbon Capture Center. ASCC can be integrated with existing FCCs or included as part of a new FCC unit.

The approximately 30% residual Scope 1 and 2 emissions from the FCC can be addressed by enhancing the energy efficiency of the unit (UOP, 2021). Some examples for achieving this include the installation of proprietary equipment and increasing both the degree of heat integration and energy recovery via the implementation of high-efficiency column internals and heat exchangers. Further energy optimisation can be achieved by installing power recovery turbines and dividing wall columns. A key advantage apart from carbon footprint reduction of these solutions will be improved unit profitability as a result of reduced utility requirements, which will be especially impactful in regions with higher utility costs. For all these spaces, Honeywell UOP has offerings that are ready now and have been commercialised to a large extent.

By leveraging its extensive design, service, and innovation experience in FCC and the oil and gas industry, Honeywell UOP can provide FCC operators with a portfolio of solutions and a roadmap for decarbonising both the FCC unit and the refinery as a whole to most effectively address the energy transition.