Cyan Ammonia FPSO
September 2023
After a year of R&D, we filed our formal patent for an FPSO capable of producing H2 and/or NH3. The Cyan Ammonia FPSO is targeted for flared and stranded gas around the world with the option of replacing the front-end of the plant (i.e., the gas to H2) with electrolyzers in the future enabling the facility to be repurposed to produce H2/NH3 from renewable energy when these technologies become economically viable.
While the FLNG solution is suitable for dry gas fields and shallow-sheltered waters, it is challenging to commercialize in un-sheltered water and for rich gas. It is almost impossible to commercialize offshore stranded gas where the LNG production is below 1 MMTPA (133 mmscfd)
What we discovered during our research (and analysis of 70 associated gas streams from 200 fields) was that the heating value of the associated gas, currently being flared or reinjected, can range from dry to very wet (1760 btu /scf), with an average heating value of roughly 1250 btu /scf. This gas may also be water-wet, dirty (H2S) and contain CO2.
Below is a sampling of the gas compositions for half-a-dozen associated gas streams which are either currently flared or re-injected.
|
|
FPSO A |
FPSO B |
Site C |
Site D |
Site E |
Site F |
|
C1 |
76 |
75 |
78.1 |
62.5 |
63.4 |
46.7 |
|
C2 |
10 |
10 |
5.2 |
14.5 |
14 |
12.7 |
|
C3 |
7 |
8 |
5.5 |
8.4 |
10.9 |
15.8 |
|
C4 |
1 |
2 |
2.1 |
8.4 |
3.2 |
5.2 |
|
C5 |
2 |
2 |
3 |
1.2 |
3.1 |
8.2 |
|
C6 |
1 |
1 |
1.8 |
0.4 |
1.5 |
3.2 |
|
C7 |
0 |
0 |
1.5 |
0.3 |
1 |
2.6 |
|
C8 |
0 |
0 |
0.5 |
0 |
0.9 |
2.4 |
|
C9 |
|
0 |
0.1 |
0 |
0.8 |
0.8 |
|
BTU /SCF |
1,157 |
1,235 |
1,223 |
1316 |
1,419 |
1,760 |
LNG is sold internationally at very specific heating values. The US market typically demands a product which is around 1050 btu /scf while the far east markets desire LNG with a heating value between 1250-1350 btu /scf (i.e., inclusive of LPG). Further, the LNG process requires contaminants (H2S, CO2, Water) removed to PPM levels prior to liquefaction.
The gas-to-NH3 process does not have these same limitations. It does require the removal of H2S, but contaminant such as Water and CO2 do not have to be removed. Additionally the heavier hydrocarbons can also remain in the feed gas.
For smaller scale lean-gas developments (66 mmscfd), we envision leaving the heavier hydrocarbons in the gas fed to the reformer. For plants where the associated gas heating value combined with rate is sufficient to justify recovery of the NGLs and LPGs, we propose to do just that.
Hence the Cyan Ammonia FPSO New-Build Hull is envisioned to:
- Receive wet, dirty, associated, flared or stranded gas
- Produce H2 and NH3
- Store and offload NH3 at up to next-gen VLGC parcel sizes
- Optionally export H2 via pipeline
- Optionally recover, store, and offload LPGs at up to next-gen VLGC parcel sizes
- Optionally recover, and compress the produced CO2 for EOR or CCS.
- monetize the LPG in the associated gas,
- monetize the natural gas at 4X Henry hub, and
- monetize CO2 either for EOR (i.e, maintain pressure in the reservoir) or CCS
