09_DesignBasis_2

7/28/2019 09_DesignBasis_2

1/9

GE PROPRIETARY INFORMATION Design Basis Page 9.1

Firm Proposal 703976 (12/07) Rev 0 ky

9. Design Basis

9.1 Fuel System Design Conditions

9.1.1 Gas Fuel

The gas fuel shall have the physical and chemical characteristics required in the attachespecification GEI 41040 and in the Design Basis.

Allowable gas fuel supply conditions at the inlet flange of the final coalescing filter (see filtratio

efficiency below) Pressure range: 19.4 to 24.2 barg

Temperature: GE currently requires the Gas Fuel supplied at terminal poinconnection to be superheated. The requirements and basis of this superheat ardefined in Specification GEI41040. If sufficient superheat is not supplied, liquidhydrocarbons may condense inside the gas fuel stream and result in damage tunit hardware.

GE requires the use of a redundant continuous Hydrocarbon dew point analyzewhich shall be a 4-20mA analog signal from the plant level control system tha

represents the real time measurement of the Hydrocarbon dew point of the gafuels.

Minimum temperature based on the contractual gas composition below icalculated in order to be compliant with GEI 41040 regarding the hydrocarbodew point, the water dew point and the maximum Modified Wobbe Inderequirement.

Maximum temperature : Consistent with range of Modified Wobbe Index variation

Gas fuel name NEW NG

Maximum hydrocarbon dewpoint (C)

-4

Maximum moisture dew point(C)

-25

Calculated minimumtemperature (C)

23


2/9



Calculated maximumtemperature (C)

88

Modified Wobbe Index range(min/max) (Btu.Scft-1.R-1/2)

46.5 51.4

Maximum Transient supply pressure excursions are limited to either 1% per

second ramp or 5% step. The 1% per second ramp is applicable over the range ofminimum required pressure to maximum operating pressure. The 5% step isapplicable over the range of minimum required pressure to 95% of maximumoperating pressure and with a maximum of one 5% step change in 5 seconds.

Note: Transient Supply Pressure operation applies to brief periods associated with pressure contromode transfers such as transfer between gas fuel pressure regulating valves, gas compressochangeovers or gas supply source changeovers, or rapid fuel demand transients such as Gas Turbinload rejections or trips.

The steady state gas supply pressure regulation at any operating point within thegas turbine capability shall remain within more or less 1 % pressure at a rate not

to exceed more or less 0.25 % / sec over the range of minimum required pressureto maximum operating pressure.

In case of use of a pressure boosting compressor, no oil content shall be present inthe fuel gas.

Filtration efficiency (absolute removal efficiencies): all solid particles whose size isgreater than 0.3 microns shall be filtered with an efficiency of 99.99% and all liquidparticles whose size is greater than 0.3 microns shall be filtered with an efficiencyof 99.5%.

Wobbe index variations:

Wobbe index variation range, with temperature correction, shall not be morethan more or less 5% during start up sequence.

Wobbe index variation range, with temperature correction, shall not be morethan more or less 5% during normal operation.

During normal operation, the wobbe index variation of the gas fuel withtemperature correction shall not be more than 0.3% per second andtemperature rise shall not exceed 1C/s

Wi = LHV / Sqrt (Sg * T)

Where:

LHV: Low Heating Value (kJ/Nm3)

Sg: Specific gravity relative to air

T: absolute Temperature (Kelvin)


3/9



The gas fuel analysis used as design criteria and for performance calculation is as per :

After normalization of contents :

Gas Composition %vol NEW NG

N2 1.3779

CO2 2.8355

H20 0.0032CH4 87.5832

C2H6 6.2143

C3H8 1.225

I C4H10 0.2612

N C4H10 0.2573

I C5H12 0.1004

N C5H12 0.0586

C6H14 0.0449

C7H16 0.0278C8H18 0.0096

C9H20 0.0011


4/9



9.1.2 Light Distillate

Light distillate fuel shall be in accordance with specification GEI 41047 category "true distillate-lightspecially regarding trace metal contaminants.

Supply conditions at inlet flange of the light distillate forwarding pumps skid:

Gravity flooded Minimum pressure: 6 mLC of required NPSH at 400 mm above the topof the forwarding skid pedestal

Maximum pressure: 2.5 bar(g)

Temperature: Higher than pour point and waxes melting point and consistent with therequired viscosity

Viscosity: 1.8 to 10 cSt (without downstream liquid fuel heating)

Flash point : must be higher than 50C

isolating valves should be avoided in the return piping between the filtering skid and the storagetank. The point of the discharge into the storage tank shall be above the maximum liquid level so thaa rupture will not drain the tank. The minimum level in the storage tank shall be at least 0.5 m abovthe top of the forwarding skid pedestal.

A return piping between the filtering skid and the storage tank will be able to (refer to technicamemo table) flow and sized for max 2.5 bar counter pressure at skid outlet flange (including tanheight).

As the piping between the forwarding skid and the filtering skid is not included in the GEEPE scopethe maximum pressure drop between these two skids must not exceed 1 bar.

The light distillate fuel analysis used as design criteria and for performance calculation is as per :

Liquid Fuel Analysis HSD

Characteristics

Lower Heating Value [ kJ/kg] 42 525

Pour Point [ C] < 15 **

Flash Point [ C] > 60

Carbon/Hydrogen ratio _

Carbon Residue [Wt (%)] _

Sulfur [Wt (%)] Max 0.5

Viscosity at 30C [cST] 1.6 - 5.8

Viscosity at 100 C [cST] > 1.0

Nitrogen [Wt (%)] _

H2O [Wt (%)] 0.05 max

Gravity API _

Gravity Specific 0.815 - 0.870


5/9



Na + K (ppm) Max 1

Va (ppm) Max 0.5

Ash (% wt) Max 0.01

Sediment content (% wt) Max 0.01

Lead 0

Nota :

** Pour point given in Addendum n3 for bid document is not compliant with GEI 41047 requirements :

it must be less than 15C.

9.2 Lube OilThe lube oil shall be in accordance with attached specification GEK 28 143.

9.3 Washing Water

9.3.1 Compressor Washing Water (On-Off Line)

9.3.1.1 Water quality

Compressor washing water shall be in accordance with GEI 41042.

Water quality required for compressor washing:

Refer to table 1 of GEI 41042

In addition to previous requirements, following should apply for on line water washing:

Silica : < 5 ppm

Conductivity : < 1 microS/cm

Note that for turbine washing, level of water quality required is the same as for off-line compressowashing.

Chemical content of washing detergent:

Refer to table A1 of GEI 41042

9.3.1.2 Water requirements

For details, please refer to GEI 41042.

Depending on the turbine frame, the flow adjustment and on the duration, the quantity of waterequired for a complete off-line washing sequence will vary from 2.7 m3 to 6.54 m3 for compresso


6/9



washing only and from 7.8 m3 to 20 m3 for turbine washing. Off-line water washing shall be done aa compressor inlet temperature not less than 4C.

For each compressor on-line washing, 1150l to 3300l of water will be necessary.

9.4 Cooling Water

9.4.1 GT and generator Cooling Water (for GEEPE Closed Circuit)

9.4.2

The cooling water quality for closed loop shall be in accordance with the specification. GEI41004

9.5 Compressed Air Quality

9.5.1 Compressed Air for InstrumentQuality Pressure Flow

LDO filtering skid 4 to 10 barg 1Nm3/h)

9.6 Electrical Auxiliary ConsumptionWorst case Gas fuel Liquid fuel

During base loadoperation

299 kW 308 kW

During starting period 281 kW 290 kW

During stand-byperiod

154 kW 154 kW

At design temp of 32C Gas fuel Liquid fuel

During base loadoperation

284 kW 293 kW

9.7 Noise Level Data

The average sound pressure level measured at a distance of 1 meter from the gas turbine turbinegenerator set and at 1.5 m height above ground shall not exceed 85dB(A).


7/9



Estimated Sound Power Levels at Base Load, dB(Ref.1 picowatt)

Please note that the sound power levels below are being provided only for use in modeling the noiseof plant. They are not guaranteed. The values are per unit

A) PWL of the GT acoustic enclosure, with its ventilation system

Sound Octave Band Center Frequency, Hertz

Power Level 31,5 63 125 250 500 1K 2K 4K 8 K dB(A)

Lw 115 112 109 100 99 96 95 94 91 103

Ref : 10-12 Watt Above and below, values in linear decibel (without being weighted)

B) PWL of the Gas Module acoustic enclosure, with its ventilation system



Lw 95

C) PWL of the GENERATOR (without screen effect)



Lw 107 107 122 111 103 104 112 97 87 114

D) PWL radiated exhaust duct



Lw 112 108 103 98 95 94 94 88 83 100

E) PWL emitted at the flange of the LF exhaust silencer



Lw 126 121 117 117 116 111 105 107 112 118

F) PWL emitted by the air inlet filter opening



Lw 111 105 89 75 73 71 75 78 83 86

NOISE OF THE SELF CLEANING

Its not a permanent noise source.


8/9



Duration of a complete cycle : 15 minutes

Number of element cleaned per pulse : 6

Number of pulse (std configuration) : 26

Duration of one pulse : 0,1 second

Pulse cleaning noise (temporary source)

Lp @ 50m Lw

Leq (1h) for one cycle 52 dBA 94 dBA

Leq (15min) for one cycle 58 dBA 100 dBA

Leq (T=1s) for one pulse 73 dBA 115 dBA

G) PWL of the GT inlet duct



Lw 105 107 102 96 93 92 104 97 95 107

H) PWL of the fin fan coolers



Lw 107 106 105 105 103 98 94 88 107

NOISE RELEVANT STANDARDS

Please refer to the Codes and Standards chapter.

TEMPORARY NOISE SOURCES

Are considered as temporary noise sources:

The noise emissions emitted by the atmospheric safety relief vent valves.

These temporary noise sources are not taken into account in our data or calculation.

9.8 Exhaust DataPlease refer to exhaust interface specifications:

N 91-447133 (lateral exhaust, LF silencer outlet flange)


9/9



9.9 Voltage and Current Levels

11.5 kV Generator Outgoing

Rated voltage: 11.0 kV

Rated frequency: 50 Hz

Number of phases: 3

Neutral earthing mode: MW resistance

400 VAC Switchboard (Motor Control Center)

Rated voltage: 400 V +/- 10%

Rated frequency: 50 Hz +/- 2%

Number of phases: 3

Neutral: Solidly earthed

Not distributed

230 VAC UPS

Rated voltage: 230 V


Number of phases: 1

power 3000 VA

230 VAC

Rated voltage: 230 V


Number of phases: 1

125 V-DC Switchboard (distribution)

Rated voltage: 125 V+ 10% - 16%

Earthing mode: Isolated

9.10 Codes and Standards

The used codes and standards for the Gas Turbine Generator and its auxiliaries are listed in theCodes and Standards chapter.

For others codes and standards not mentioned in this specification, Manufacturer standards shaapply.

Documents

09_DesignBasis_2