Purge to atm.
Water Air
ASU and/or electrolyser
Green/blue energy
Others
CO capture
O
H O
UOP
Recycle blower
20-30% of total flow
70-80% of total ow
Synthesized air (CO + O )
CO recycle
Reactor vapours
Third stage separator (optional)
SH steam
BFW
100% of total ow
Regenerated catalyst
Electricity
nViro FCC De-SO & PM removal x
Regenerator (coke combustion)
DeNO x
Reactor
KOD
HRSG
PRT (optional)
Cooling/ condensing
Spent catalyst
BFW
Blowdown
Fresh feed Recycle(s) Steam
H O CO product
BFW
Flue gas under ow
Large catalyst nes
Blue/green MeOH SAF (via HON UOP eFining) Other CO utilisation routes
Green H
Figure 4 Honeywell UOP Synthesized Air FCC enables several CO2 utilisation pathways
operation, the drop in regenerator temperature and flue gas volumetric flow unlocks additional coke burn capacity in the regenerator. This feature can be leveraged by increas - ing the reactor coke make, which provides the opportu - nity to increase the residue component in the feed blend. Alternatively, the possibility of increased coke burn capac - ity in the regenerator provides an opportunity to increase the feed processing capacity of the FCC unit up to 30%, provided the reactor and downstream separation system can handle the additional flow rate. d • The large (70-80 mol%) flue gas recycle for the synthetic air FCC units results in less Capex and Opex required for the CO2 capture system since it can be smaller due to only processing 20-30 mol% of the total flue gas. • The main utility required in the CCU is electricity as com - pared to steam in traditional solvent-based CCUs to regen - erate solvent in the stripper section. • For a new FCC unit, the higher molecular weight of CO2 enables a size reduction of the regenerator and flue gas section. • If nViro FCC is included in the flow scheme, the heat recovery from the flue gas stream can be increased, leading to improved process energy efficiency. • Can enable more bio-renewable feed co-processing
(O2- rich feedstocks) due to the larger heat sink in the regenerator. Note that processing bio-renewable feed - stocks, due to higher feed oxygen content, can result in more coke to the FCC regenerator, thereby increasing the FCC regenerator temperature. The mechanism behind this higher coke level is a deoxygenation pathway consuming hydrogen to produce water (H2 + O2 H2O), resulting in reduced hydrogen availability, which can result in higher coke make5 , 8 and subsequently higher regenerator temper - atures. Having a larger heat sink in Synthesized Air FCC when operating in ‘constant volume operating mode’, one will be able to process more biogenic feedstock without running into regenerator temperature constraints. • Represents a carbon capture complex with a positive return on investment without having to rely on any form of CO2 reduction incentives/tax due to the ability to process more feed and/or more opportunity feedstock, as per Table 1. • Use of typical hydrocarbon refrigerant(s) (such as pro - pane) in refineries. Carbon capture options enabled by synthesised air mode of FCC catalyst regeneration mode CO2 capture is achievable in both traditional air combus - tion 1⁰ and Synthesized Air FCC units. For traditional air
Simple payback with Honeywell UOP Synthesized Air FCC with 20% higher coke burn
Simple payback
Reduced feed costs
Increased yields
Utilities/oxygen *
Carbon credit
Payback
Additional 20% coke burn (alternate feed blend)
$0/t Carbon Credit $50/t Carbon Credit $100/t Carbon Credit $150/t Carbon Credit
$51.8 MM/yr $51.8 MM/yr $51.8 MM/yr $51.8 MM/yr
N/A N/A N/A N/A
$28.3 MM/yr $28.3 MM/yr $28.3 MM/yr $28.3 MM/yr
$0 MM/yr
4.8 yrs 2.7 yrs 1.8 yrs 1.4 yrs
$19.2 MM/yr $38.4 MM/yr $57.6 MM/yr
* Oxygen concentration in synthesised air stream to regenerator is 21.5 – 22 mol%.
Table 1
22
PTQ Q4 2023
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