Effective and efficient removal of hydrogen sulfide (H2S) is an essential step when sweetening gas for downstream processes. By simultaneously turning the captured hydrogen sulfide into elemental sulfur, a Frames THIOPAQ O&G system improves gas value, while creating a saleable chemical widely sought after in the agricultural and bulk chemical industry.

1. SPE 172058 Sweetening and Sulfur Recovery of Sour Associated Gas and Lean Acid Gas in the Middle East
Peter Hauwert, Ph.D. - Frames

2. Sour Associated gas
Flaring
•Middle East annually flares 29 BCM of associated gas [1]
•Feed for 20 mtpa LNG plant (12 B$ @ 12 $/MMBTU)
Reserves
•57% contains <0.1%v H2S [2]
•32% contains 0.1-1%v H2S Non-produced gas with GOR>1000 scf/bbl, for values available in IHS EDIN
Small SRU
•Relevant for >25% of gas currently not produced
BCM = 109 m3 MT = 109 kg Tscf = 1012 scf = 28 x109 m3 [1] World Bank - Global Gas Flaring Reduction partnership (2007) [2] Golombok (Shell), E&P 2008 (from IHS EDIN database)
<100 ton/d S: <0.1%, <0.5%,<1% H2S
6.2

3. Outline
Sulfur recovery process comparison
Thiopaq O&G Process
Process in desert environments
Case study

4. 100 kg/d S
1 t/d S
10 t/d S
50 t/d S
200 t/d S
10
100
1,000
10,000
100,000
1,000,000
0.1
1.0
10.0
100.0
H2S cocentration in feed (%vol.)
Feed gas Flow (x106 Nm3/d)
Assessment of RFQs for H2S containing feeds (up to 2012)
(1 x106 Nm3/d ≈ 37 MMSCFD)
100% H2S 10% H2S 1% H2S 0.1% H2S 1000 ppm 100 ppm 10 ppm
Small Scale Sulfur Recovery
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 4 / 22

5. Small Scale Sulfur Recovery

6. Small scale sulfur recovery processes
Aqueous iron
Thiopaq O&G
CrystaSulf
Catalytic oxidation
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 5 / 22

7. Comparison commercial small scale SRU
Aqueous iron
Thiopaq O&G
Crysta Sulf
Catalytic oxidation
Sulfur load (tonne S/d)
1-20
1-100+
1-20
1-20 (-200)
H2S removal (%)
99.9+
99.9+
>99.8
90 % /pass
H2S specification (ppmv)
< 4
< 4 (> 4 bar)
< 25 (atm)
< 4
4-100
Pressure
<30 bar
LP / HP
HP
LP / HP
S quality
Landfill
Agro / Claus
Claus
Claus
Operational since
‘70s (LoCat)
‘90s (Sulferox)
1993 (biogas)
2002 (NG)
2005
2005
References
> 200 (LC)
> 30 (SF)
> 200 (bio)
16 (NG)
< 5
< 5
Operations & HSE
-
++
+
+
Comments
Foam issues
Water consumption
SO2 needed
Only <10% H2S

8. Adapted from: Lee, GPA Europe 30th Annual Conference, (2013)
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 7 / 22

9. •Low pressure gas
o1887 – Winogradsky discovers sulfur oxidizing bacteria
o1989 – Buisman develops Thiopaq process
o1993 – Thiopaq pilot plant at wastewater treatment Eerbeek
o1994 – 1st Commercial unit by Paques (water treatment)
o2014 - >200 commercial references (biogas)
•High pressure gas
o1997 – Thiopaq O&G tests at 60 bar natural gas (with Shell)
o2002 – 1st commercial Thiopaq O&G unit
o2014 – 16 commercial references (natural gas / acid gas / associated gas)
Thiopaq O&G - History
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 8 / 22

10. Thiopaq O&G – Process description
Bioreactor
Decanter
Sulfur
Air out
Air in
Flash gas
Feed gas
Product gas
Condensate
NaOH water nutrients
( )
Feed pre-treatment Absorber Regeneration Solid sulfur separation
Bleed
Flash
(optional)
Settler
Absorber
H2S + OH-  HS- + H2O
CO2 + OH-  HCO3
-
with carbonate buffer (pH 8.0-9.5)
Regenerator
HS- + ½ O2  Sx + OH-HCO
3
-  CO2 + OH-HS-
+ 2 O2  SO4
2-
+ H+
2 HS- + 2 O2  S2O3
2- + H2O
Control
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 9 / 22

11. Thiopaq O&G in the Middle East?
?
?
?
?
?
?
?
“It’s hot!!”
“We don’t have water”
“They’re bacTeria”
“what do I do
wIth the sulfur?”
“Is it proven?”
(Feedback we have had from clients)

12. Technical applicability in desert
•Ambient conditions
o-5 oC (night, desert) up to 55 oC (summer daytime)
oBlack bulb temperatures up to 85 oC
•Remote operation
oManpower for operation
oMaintenance
•Remote construction
oTransportation difficulties
oQuality control
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 11 / 22

13. Applicability – Ambient temperature
•Feed gas cooling
oHydrocarbon dewpoint (30-35 oC)
oSlugs: well-fluids and heavy hydrocarbons
oStabilizes operation of absorber
•Solvent cooling (40 oC)
oAbsorption & reaction enthalpy
oBacteria 35-45 oC optimal
 Cooling system (60-100 kW / ton S)
 Insulation
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 12 / 22
BioreactorDecanterSulfurAir outAir inFlash gasFeed gasProduct gasCondensateNaOH water nutrientsFeed pre- treatmentAbsorberRegenerationSolid sulfur separationBleedFlash (optional) SettlerCooling system

14. Applicability – Solar irradiation
•Solar irradiation
o1600-2800 kWh / m2  Black bulb temperature 85 oC
 Light / reflective coating
 Shading
 Insulation of piping
Adapted from SolarGIS © 2014 GeoModel Solar
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 13 / 22
Thiopaq O&G plant constructed in Egypt:
Kijlstra, Laurence Reid Gas Cond. Conf (2001)

15. Applicability – Remote operation
•Stable operation
oLarge buffer solution
oAdaptive bacteria
•Suitable for associated gas
o Unstable feed flow
o Changing concentrations
Plant operation data in Netherlands plant,
courtesy of Paques B.V.
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 14 / 22

16. Applicability – Remote operation
•Limited operator attention
oSimple control loops
oMinor daily analyses & maintenance
oRobust operation
oAmbient conditions
oSimple start-up & shutdown
•Limited maintenance
oMain equipment static columns & tanks
oRotating equipment installed spares
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 15 / 22

17. Applicability – Remote operation
•Consumables
oPotable water quality
oTransport by truck or on-site generation (well)
oCaustic
oNutrients
oNo fuel gas needed & limited power consumption
•Case by case CAPEX-OPEX evaluation necessary
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 16 / 22

18. Applicability – Remote construction
•Modularized construction
oMain vessels  road transportable
oPumps & small equipment  skid-mounted
oControlled manufacturing environment
oLimited site work
•Fast track possible
oNo higher alloys (Incoloy / Titanium /Duplex)
oLimited long-lead items
oStandardized design
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 17 / 22

19. Case study
•Impact of desert environment – case study
oTypical associated gas composition 0.5%v H2S, 5%v CO2
o550 kNm3/d [20 MMSCFD] (40 oC, 3 bar)  4 tpd S
oWestern Europe vs. Middle East
•Design: 165 m3/h solvent circulation (For more details see paper)
o1 absorber (1.8 m ID x 18.3 m TT) & 3 aerated tanks (4.0 m ID x 8.1 m TT)
•Consumables: 1 m3/d caustic (50wt%) & 17 (ME)-18 (EU) m3/d water
•Power:
oFeed cooling (78 kW) & Solvent cooling (158 kW, EU / 226 kW, ME)
oAir blower (110 kW) & Pump duty (35 kW )
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 18 / 22

20. Case study – Design
Middle East
Western Europe
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 19 / 22

21. Case study – Relative CAPEX
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 20 / 22
106%
100%

22. Conclusions
•Small-mid scale sulfur recovery processes compared
oSeveral maturing options available
oThiopaq O&G technically and commercially attractive
•Thiopaq O&G suitable for sour associated gas treatment
oGood performance also at low pressures
oRobust toward variations in feed
oSweet spot for associated gas
•Thiopaq O&G applicable in desert environment
oLimited impact of ambient conditions on overall costs
oLow operator attendance
oModular construction possible
SPE172058 • Sweetening and Sulfur Recovery of Associated gas in the Middle East • Peter Hauwert • 21 / 22

23. Slide 23
Frames Lennard Spit Paul Mulders Hein Kandelaar Lex Rotteveel Elwin Janssen Paqell Gijs van Heeringen Hans Wijnbelt Paques Erik van Zessen
Acknowledgements
Thank you for your attention