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No flares but electricity
Jacob KLIMSTRA
Wärtsilä Power Plants150 Gm3/year flared
6% of worldwide gas use
1.5% of Total Primary Energy Supply
A reciprocating engine + generator : the solution
Example: High fuel efficiency of a reciprocating engine
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Electric power (%)
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flat efficiencyHeat fraction
Combined efficiency
electrical efficiency
The common Otto-cycle gas engine: the challenge of gas quality
–Knock resistance: methane number > 60
–Dry, sweet and free of condensates and particles
But: we have the Gas-Diesel engine GD
Exhaust Intake
The gas – diesel (GD) working principle
–Diesel fuel serves as the igniter–Gas is injected simultaneously with the diesel– Knocking can not occur
Exh
Air Intake Compression of AirInjection of Gas
and Pilot Fuel Ignition
Exh ExhAir Air Air
GD Gas operation mode
Constant fuel amount at 3 - 5 % of 100 % load
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Load %
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Gas
Liquid
Fuel specs for the GD
Fuel property Min./max. Limit Unit
Lower heat value min. 30 MJ/Nm3 2)
Gas supply pressure to engine 1)
max. 350 ± 5 bar
Gas temperature before engine max. 50 °C
Methane (CH4) min. 60 vol.-%
Carbon dioxide (CO2) max. 30 vol.-%
Chlorine's + fluorine's max. 50 vol. ppm
Hydrogen sulphide (H2S) max. 500 vol. ppm
Other sulphides or mercaptans max. 50 vol. ppm
Water (H2O) max. 100 vol. ppm
Particles or solids size max. 10 m
1) 310 bar for engines with max output 85% D output
2) Nm3 defined at 0°C, 1.01 bar
Reference: Dygoil
• Dygoil, Equador– 2 x Wärtsilä® 16V32GD– 11MWe– The power plant started up
in March 2004, and it operates with oil field associated gas as the main fuel, and Crude oil as supplementary fuel
– The plant is designed to utilize the associated gas and to minimize the need for flaring, and unnecessary CO2 emissions are avoided
No power problem if the gas flow varies
diesel pilot
gas and oil share
adjustable
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Fuel Sharing
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Engine load%
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GD operation
Transfer window
Fuel Sharing
GD Engines power range
Engine Type Wärtsilä 32GD Wärtsilä 46GD
Cylinder bore, mm 320 460Speed, rpm 720 / 750 500 / 514Heat Rate (ISO), kJ/kWhe 8,270 [43.5%] 8,050 [44.7%]
Fuel oil qualities Diesel oil Diesel oilHeavy fuel oil Heavy fuel oilCrude oil Crude oil
Gas qualities Natural gas Natural gasAssociated gas Associated gas
Cylinder configurations- V-form 12, 16, 18 12, 16, 18
Generator power, kWe 4,320 – 6,500 11,300 – 17,000
Gas LHV = 30 MJ/Nm3, dicharge pressure = 350 bar(a)
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18V32GD
16V32GD
12V32GD
Compression power
350 bar
kW
4.6% of power
bar
43.5 * 0.954 = 41.5 %
Other possibilities at the horizon
GASPAC®
any gas methane
inverse reformer
For YOU to remember:
• Flaring can be reduced and the gas can be used with high:
1. Fuel flexibility2. Power flexibility3. Fuel-to-power efficiency
Wärtsilä can help you