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Sweetening and Sulfur Recovery
of Sour Associated Gas
in the Middle East
Peter Hauwert
Presented at the 30th ADIPEC
SPE 172058
Sour Associated gas
Flaring
• Middle East annually flares 29 BCM of gas [1]
• Feed for 20 mtpa LNG plant(12 B$ @ 12 $/MMBTU)
Reserves
• 57% of gas <0.1%v H2S [2]
• 32% contains 0.1-1%v H2SNon-produced gas > 1000 scf/bbl, 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
OutlineOutline
Sulfur recovery process
comparison
Thiopaq O&G Process
Process in desert
environment
Case study
100 kg/d S1 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
co
cen
trati
on
in f
eed
(%
vo
l.)
Feed gas Flow (x106 Nm3/d)
Assessment of RFQs for H2S containing feeds
100% H2S
10% H2S
1% H2S
0.1% H2S
1000 ppm
100 ppm
10 ppm
Small Scale Sulfur Recovery
Small scale sulfur recovery processes
Aqueous iron Thiopaq O&G
CrystaSulf
Catalytic
oxidation
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 Input <10% H2S
Comparison small scale SRU
Adapted from: Lee, GPA Europe 30th Annual Conference, (2013)
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-
HCO3-
CO2 + OH-
HS- + 2 O2 SO42- + H+
2 HS- + 2 O2 S2O32- + H2O
Control
Thiopaq O&G in the Middle East?
??
?
??
??
“It’s hot!!”
“We don’t have water”
“They’re bacteria”
“Is it proven?”(Feedback we have had from clients)
“what do I do with the sulfur?”
Applicability – Ambient Conditions
• Ambient temperature & solar irradiation
• Feed gas cooling & knockout
o Hydrocarbon dewpoint (30-35 oC)
o Well-fluids and heavy hydrocarbons
o Stabilizes operation of absorber
• Solvent cooling (40 oC)
o Absorption & reaction enthalpy
o Bacteria 35-45 oC optimal
Cooling system (60-100 kW / ton S)
Insulation
Adapted from SolarGIS © 2014 GeoModel Solar
ThioPaq plant constructed in Egypt:
Kijlstra, Laurence Reid Gas Cond. Conf (2001)
Applicability – Remote operation
• Limited operator attention
o Robust operation
o Daily analyses & maintenance
o Simple start-up & shutdown
• Limited maintenance
o Main equipment: static tanks
o Rotating: installed spares
• Consumabes
o Caustic, nutrients & potable water
o No fuel gas, limited power on pumps & coolingPlant operation data in Netherlands plant,
courtesy of Paques B.V.
Applicability – Remote construction
• Modularized construction
o Main vessels road transportable
o Pumps & small equipment skid-mounted
o Controlled manufacturing environment
o Limited site work
• Fast track possible
o No higher alloys (Incoloy / Titanium /Duplex)
o Limited long-lead items
o Standardized design
Case study
• Design: 165 m3/h solvent circulation
o 1 absorber (1.8 m ID x 18.3 m TT)
o 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:
o Feed cooling (78 kW)
o Solvent cooling (158 kW, EU / 226 kW, ME)
o Air blower (110 kW) & Pump duty (35 kW )
• Impact of desert environment – case study
o Typical associated gas composition 0.5%v H2S, 5%v CO2
o 550 kNm3/d [20 MMSCFD] (40 oC, 3 bar) 4 tpd S
o Western Europe vs. Middle East
Case study – Design
Middle East
Western
Europe
Case study – Relative CAPEX
106%100%
Conclusions
• Small-mid scale sulfur recovery processes compared
o Several maturing options available
o Thiopaq O&G technically and commercially attractive
• Thiopaq O&G suitable for sour associated gas treatment
o Good performance also at low pressures
o Robust toward variations in feed
o Sweet spot for associated gas
• Thiopaq O&G applicable in desert environment
o Limited impact of ambient conditions on overall costs
o Low operator attendance
o Modular construction possible
Thank you for your attention
Acknowledgements
Frames
Lennard Spit
Paul Mulders
Hein Kandelaar
Lex Rotteveel
Elwin Janssen
Paqell
Gijs van Heeringen
Hans Wijnbelt
Paques
Erik van Zessen