NWK Startup Procedure

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North West Khilala Start-up ProcedureFor Disouq Field

Document Title: North West Khilala Start-up ProcedureVersion: V02

Date:Prepared By: Mohamed Samir / Khaled Tawakol

Reservoir Engineer

Reviewed By: Bronislav Vago

Deputy Reservoir Engineering

Checked By: Bernd Wirth

Deputy Pet. Gen. Mgr.

Mohamed El khayat

Pet. Gen. Mgr.

Approved By: Mike Schreiter

Deputy Operations General Manager

Operations General Manger

Distribution List

[1] Chairman and MD & General Manager and MD (2 copies)

[2] Operations General Managers (2 copies)[3] District Field Managers (2 copies)[4] Technical General Manager (1 Copy)[5] Production General Manager (2 copies)[6] Production Specialist (2 copies)[7] Assistant General Manager for Production (2 copies)[8] Petroleum Engineering General Manager (1 Copy)[9] Reservoir Engineering Department Head (2 copies)



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Abbreviation

NWK North West Khilala

TPF Temporary Production Facilities

WGR Water Gas Ratio

CGR Condensate Gas Ratio

DHP Down Hole Pressure

DHT Down Hole Temperature

WHP Well Head Pressure

WHT Well Head Temperature

FLP Flow Line Pressure

FLT Flow Line Temperature

PLEM Pipe Line End Manifold

TRSSSV Tubing Retrievable Sub-Surface Safety Valve

ICV Inflow Control Valve

RMP Reservoir management Plan

DCS Data Control System

MCS Master Control System

ELNG Egyptian Liquefied Natural Gas

MEG Mono-Ethylene Glycol

PE Petroleum Engineering

SIWHP Shut-In Well Head Pressure

MIV Manifold Isolation Valve



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1- Introduction

NWK field consists of 3 new wells; NWK1-1, NWK1-2 and NWK1-3 in addition to one well to bedrilled in the third quarter of 2013; NWK1-4. The wells are scheduled to be commissioned in onephase through SIGMA TPF.

The objective of this document is to provide a detail plan for starting up and commissioning of thenew field.

This document covers the following main items during production Start-up and commissioning:

Priority of wells for start-up & commissioning Well Start-up Procedures Well Operating Guidelines

These procedures will be underpinned by a set of production limits/constraints aimed at maintaining

the well integrity and maximizing the recovery from the reservoirs as derived from:

Clean-up well test results for each well Critical water coning rates for each well where applicable Erosion velocity constraints for each well Maximum well deliverability established from multi rates testing Ranking of wells taking account of operational constraints and reservoir management issues

The general rules and guidelines for the wells and reservoir management of the NWK field are a partof Phase A development for Disouq field reservoir and well management plan. Operations will

operate the wells within these guidelines and any changes/deviation from these will need to beagreed between Petroleum Engineering and Operations.

2- General Description of the On-Shore Production System

This section describes the general guidelines for operating the export system from wellhead to theTPF.

2.1 General production system overview

The three NWK wells are all drilled and completed during the period from 2006 to 2012 as onshore

wells and will be tied back into the temporary production facilities.

2.2 Well Monitoring and Data Acquisition NWK Wells

In order to enable the most effective reservoir management, well monitoring and surveillance isessential. Table 1 summarizes the data available on each of the NWK wells.



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Table 1: Data available for each of the NWK wells

Well Reservoir WHP (psig) WHT (F) FLP (psig) FLTNWK1-1 Abu-Madi 2330 121 1220 N/ANWK1-2 Abu-Madi 2737 228 N/A N/A

NWK1-3 Abu-Madi 3630 118 1024 N/A

Petroleum engineering staff is to monitor the well data closely to ensure that potential wellproduction problems are identified timely and the production is optimized.

Every effort should be made by the instrument to ensure that all the gauges are working correctly.

In order to have a good understanding of well performance vs. time, it is essential that regular multirate and build-up tests are performed on each of the wells at least once every year.

3- Well Operating Guidelines

3.1 Bean Up

During bean-up high transient flows can be generated that cause fines mobilization. These can leadto increase formation skin damage, as a result of fines plugging pore throats in the near wellboreregion, and also the increased risk of sand production.

Bean-up procedures aim to reach the required well production rate in the minimum possible time,without detriment to ultimate well integrity and productivity. However, a too rapid bean-up maylead to a reduction in the long-term well performance, as well as causing sand failure and erosion ofthe production system.

The recommended bean-up procedure is based on the theory that a bean-up with a smallerincremental drawdown and short time between choke changes is superior to one with a higherincremental drawdown but a longer “waiting” time between choke changes.

The actual bean-up procedures for the various NWK wells are provided in the initial start-up sectionof this document.

3.2 Planned Shut in

It is also important to protect the wells from pressure shocks during shut-in. Therefore rapid shut-insshould be avoided wherever possible. For a planned shut-in, the well should be shut in gradually, toreduce the pressure/stress shock to the formation.

Recommended shut-in procedure is to reduce the choke setting slowly over a 15 minuteinterval until the choke valve is closed.

The wells should be closed first at the wellhead to prevent pressuring up the flow lines.

The exception to a slow planned shut-in is a shut-in for a Build-Up Test. To get analyzable data overthe initial early time build-up period wells should be shut-in at the wing valves.



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3.3 Emergency/Process Shut in

After an emergency or a process shut in it is important to let the well conditions settle beforeputting it back on production. This will avoid any additional stress on the sand face.

After an emergency or process shutdown let the wells settle for minimum 15 minutes beforere-opening the well.4- Well Data

4.1 General data

4.1.1 Petrophysical Data

The available logs for each of the wells are listed in Table 2. A summary with the interpreted andcompleted net thicknesses for each of the wells is presented in Table 2.

Table 2 - Summary of net pay from petrophysical interpretation with completion intervals

Well ReservoirPerforation Petrophysics

Top Bottom Gross Net NTGm-MD m-MD m m %

NWK1-1 AbuMadi 3098 3130 34.6 29.4 85NWK1-2 AbuMadi 3022 3046 24 17.9 75NWK1-3 AbuMadi 3019 3064 45 31.2 70

4.1.2 PVT data

PVT samples were taken from all wells. The samples were either Down-hole MDT samples or surfacesamples. A summary of the PVT data is provided in Table 5.

4.2 North West Khilala

4.2.1 Location and Reservoir Drainage

Northwest Khilala Gas Field is a 3-way dip closed combined structural and stratigraphic trap. Themain bounding fault has a NW-SE to N-S trend and extends for more than 12 km from NW KhilalaField in the north to the West Khilala Field at the southeast. The fault attains a maximum throw of

~65 m east of the NWK-1x ST1 well location and diminishes to the north. The fault also reduces inthrow to the south before transferring to via a small relay to a parallel fault which increases in throwto the south where it appears to form the eastern bounding fault of the West Khilala Field. Thewestern margin of the field comprises a low angle dip slope which encloses reservoir quality sands(Appendix I Fig. 5.3). The far angle stack response away from the well location shows good lateralcontinuity of the reservoir / hydrocarbon column below the structural closure.



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4.2.2 Petrophysics

The following table summarizes all the performed logs in NWK wells:

Well NWK1-1

12 1/4” hole: The tool run was (AIT-APS-TLDDSI-GR) 8 1/2” hole: Two logging runs were made. The first tool run was (Dual OBMI - Sonic

Scanner). The second tool run is (AIT - APS - TLD - ECS - HNGS). MDT and VSP: 44 pressure points and 2 samples were taken. Cased-Hole Logs: USIT - CBL - VDL - CCL – GR

Well NWK1-2

12 1/4” hole: The tool run was ( AIT−TLD−APS−HNGS−HCAL), ECS−HNGS−GR , Dual OBMI−GR & Sonic Scanner−PPC−GR

8 1/2” hole: Free Point Indicator & Pipe



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XPT: 28 pressure points. Cased-Hole Logs: USIT - CBL - VDL - CCL – GR

Well NWK1-3

8 1/2” hole: Three logging runs were made. The first tool run was (ZAIT-TLD-APS-ECS-HNGS).The second tool run was (Dual OBMI-MSIP-PPCGR). The third one was (CMR - GR)

MDT and VSP: 35 pressure points and 5 samples were taken. Cased-Hole Logs: CBL-VDL-USIT

4.2.3 Completion

NWK wells were completed as a single zone producer with SSD to isolate the lower part (Need tocheck the current completion).

4.2.4 PVT

A summary of the gas properties and composition for the gas from 2 different wells (NWK1-1 and 1-3) is presented in Table 6.

4.2.5 Well Deliverability

The three wells were tested at different rates with various tests (modified isochronal and flow afterflow). The expected rate from the three wells is 50 MMscf/d.

4.2.6 Pressure Build-up analysis

The final reports for the well test analysis are attached to this report in Appendix I.

4.2.7 Integrated Asset Model

The model is still under preparation, the final report will be issued after finalizing the study.

5- Well Operating Envelopes (Initial Rates)

The well operating envelopes are essentially the practical translations of the reservoir managementstrategy and the flowing operating constraints. They consider:

Well deliverability Water coning Rates Sand erosional Rate Flow assurance Rates

The critical coning rate is difficult to calculate due to unavailability of GWC and it will be critical to beestimated. For the startup it will be estimated as the maximum rate during the test as summarized intable 3. Once the wells are started up and the initial multi-rate test conducted the long termrecommended rates will be review based on well test results, operation conditions and gas demand.

Note: The constraints are based on the expected initial conditions.

Well Name Maximum Rate during Draw Down (psi) Erosional Rate at



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test (MMscf/d) scSSSv (MMscf/d)NWK-1 18 300 112NWK-2 12 450 106NWK-3 17 700 118Table 4 will summarize the expected operating range based on the current Prosper Model and will

be revised after operating the field

NWK1-1

No.Qg

MMSCFDQo

bbl/dWHFP

PsiReservoir

pressure (psi)remarks

1 10.8 11 3500 initial first day2 11.8 12 3450 initial second day3 12.8 13 3400 initial third day4 15.5 16 3250 initial production5 15.5 16 3250 initial production6 15.5 16 3150 2% depletion production7 15.2 15 3020 5% depletion production8 15.6 16 2750 10% depletion production9 15.5 16 2500 15% depletion production

10 15.4 15 2150 20% depletion production11 14.5 15 1950 25% depletion production12 13.7 14 1750 30% depletion production

NWK1-2

No.Qg

MMSCFDQo

bbl/dWHFP

PsiReservoir


1 15 15 3680 initial first day2 16.2 16 3650 initial second day3 18.1 18 3600 initial third day4 19.7 20 3550 initial production5 19.7 20 3550 initial production6 19.9 20 3450 2% depletion production7 20.2 20 3300 5% depletion production8 20.6 21 3050 10% depletion production9 19.6 20 2850 15% depletion production10 19.8 20 2600 20% depletion production

11 19.9 20 2350 25% depletion production12 20.2 20 2050 30% depletion production

NWK1-3

No.Qg

MMSCFDQo

bbl/dWHFP

PsiReservoir


1 11.5 16 3250 initial first day2 12.2 17 3200 initial second day3 12.8 18 3150 initial third day4 13.5 19 3100 initial production

5 13.5 19 3100 initial production6 13.5 19 3000 2% depletion production



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7 13.5 19 2850 5% depletion production8 13.5 19 2600 10% depletion production9 13 18 2350 15% depletion production

10 12.3 17 2150 20% depletion production11 11.3 16 2000 25% depletion production

12 10.6 15 1800 30% depletion production

6- Production Start-up Procedures for NWK Wells

In general, post any shut down, wells are to be brought online in a manner which protects theintegrity of the completions of the new wells (and any other well) without unnecessarily delaying theramp-up to the target gas flow rates to ensure that nomination is met. It is the responsibility ofPetroleum Engineering to ensure that the wells are protected from large increases in choke whichcould result in damage to the gravel pack, fines migration, and water production and ultimatelyscreen damage. It is therefore necessary to impose strict operating guidelines which minimizedisturbance to the reservoir without compromising the ability to produce more aggressively to meethigh demand.

For the initial start-up of NWK wells, special procedures have been adopted based on the status ofthe flow lines and methanol injection lines post commissioning. Prior to commissioning the wells allthe NWK flow lines will be dewatered with nitrogen and will be filled with residual water andnitrogen. The pressure of the flow line is expected to be 90 bars at the time of the start-up.

Prior to the start-up of TPF the nitrogen in the flow-line will be vented and displaced by gas from thesystem. Steady state calculations have been made to determine number of time the flow-line needsto be vented remove all the Nitrogen from the flow-line.

6.1 Pre Start up Requirements

Ensure that all the wellhead sensors and acoustic sand detectors for each well are operational andbeing read/recorded (Pressure, Temperature, Flow rate) - for all wells.

The Nitrogen will be vented from the flow-line. It has been calculated that the flow-line should bevented (and re-pressurized with gas) 2 ½ time before all the N 2 has been displaced. The N 2 will bevented at the HIPPS and the flow-line recharged with gas from the manifold side.

6.2 Start-up Schedule

Based on the current schedule it is expected that NWK will be available for start-up on the 1 st ofAugust 2013.

6.3 Starting up North West Khilala

The expected SIWHP for NWK wells are above the design pressure rating of the flow-line, thewell is tied in via a HIPPS system.

The HIPPS system must be tested and confirmed to be functioning ok prior to starting up thewell.



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NWK ties into the TPF system and a 6 ” flow line. The 6” flowline is max 3 km long. Prior tothe start-up the Nitrogen will be vented from the flowlines.

Methanol Injection will be required during start-up of the well.

Prior to start-up

All the key well instrumentation should be functioning and reading correct data. The manual manifold valves should be been opened

6.3.1 Flow Line pressurization

During initial start-up there is no pressure in the system and hence the total system requires to befilled with gas and to be pressurized. Due to the initial large pressure drop across the choke willcreate a large temperature drop across the choke at initial start-up. Methanol injection will berequired during well start-up.

6.3.2 Well Bean up Procedure for North West Khilala Wells (initial well start-up)

1- Ensure that the surface Choke is closed and HIPPS valve is open.2- Ensure that Methanol is injected via the methanol line at the tree3- If not open already open the TRSSSV4- Open Lower Master valve fully (10 steps)5- Open wing valve slowly6- Open surface choke to 3%7- Increase the rate at a maximum choke increment of 2% allowing 5-10 minutes between

choke changes

8- Continue flowing well until the pressure limit is reached then the well is closedautomatically by the HIPPS and ESD wing valve.

9- Repeat steps 6 to 8 until well can be flowed without reaching the pressure trip.10- Continue opening the choke in increment of 2% allowing 5-10 minutes between choke

changes flowing well up to gas rate of ±10 MMscfd as the 1 st rate in the multi rate test.(Choke well down if rate was already exceeded during 1 st steps) The rate duration will bedetermined by the PE supervising the start-up

11- Increase at a maximum choke increment of 2% allowing 15 minutes between chokechanges up to gas rate of ±12 MMscfd as the 2 nd rate in the multi rate test. The rateduration will be determined by the PE supervising the start-up.

12- Increase at a maximum choke increment of 2% allowing 15 minutes between chokechanges up to gas rate of ±15 MMscfd as the last rate in the multi rate test. The rateduration will be determined by the PE supervising the start-up.

13- Continue flowing well at ±15 MMscfd.14- Switch to Meg once the flow-line temp is higher than 10 deg.15- After well has cleaned-up and flowed at stabile rate for 8-10 hrs close in the well at the

PWV and choke for a PBU.16- Close MIV

Note: As the well productivity has not been established it is important that the actual performance ismonitored close against the well constraints.



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The actual timing of the flowing and shut-in periods will also depend on actual well performance.The PE on site will advise when to the timings are required.

7- MEG Requirements

When calculating the Joule-Thomson Coefficients for the process (220 bar and 40 °C) to 90 barexpansion. The temperature decrease is about 32 °C.

The cooling into account the required methanol amount was calculated assuming a 100 % water wetgas stream.

The water content of the gas stream is calculated to 8 kg/MMscf of gas @ 220 bar and 40 °C whatequals 0.032 mass% of water in the gas.

Simulation with PVTSim:

With this water content the minimum inhibitor concentration was calculated for the process,assuming a cooling to 8 °C and 90 bar: methanol requirement 1.5 kg of methanol/1 kg of water.

When taking 1.5 kg of methanol (density of 790 kg/m³) per 1 kg of water the methanol amount sumsup to 12 kg of methanol per MMscf of gas.

This is equal to 15 liters of methanol per MMscf of gas.

When using a different software tool (University of Freiberg) the methanol amount is calculated to16 kg what equals 20 liter of methanol per MMscf of gas.

Following recommendation: Because of a cooling up to 32 °C methanol is required as hydrate inhibitor for start-up phase 15 liters of methanol per MMscf of gas should be sufficient to prevent hydrate formation;

hydrate curves attached For higher water contents of the gas the required amount of methanol is lower – so no concern



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HYDRATE CURVE



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Table 5-a – Summary PVT Data of Well NWK1-1

Sample Shown TS-1332-01/a3155

Type of Sample Separator Mathematical Recombination

Component Mole % Component Mole %

N2 0.078 C 13 0.027

CO2 0.786 C 14 0.017

H2S ---- C15 0.012

CH4 97.760 C 16 0.008

C2 0.757 C 17 0.006

C3 0.106 C 18 0.004iC4 0.034 C 19 0.003

nC4 0.017 C 20 0.002

iC5 0.028 C 21 0.002

nC5 0.009 C 22 0.002

C6 0.027 C 23 0.001

MCP 0.003 C 24 0.001

Benzene 0.008 C 25 0.001

C7 0.109 C 26 0.001

Toluene 0.002 C 27 0.000

C8 0.090 C 28 0.000

Ethyl Benzene 0.004 C 29 0.000

m - Xylene 0.007 C 30 0.000

p - Xylene 0.021 C 31 0.000

o - Xylene 0.008 C 32 0.000

C9 0.010 C 33 0.000

C10 0.013 C 34 0.000

C11 0.012 C 35 0.000

C12 0.018 C 36+ 0.000



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Table 5-b – Summary PVT Data of Well NWK1-2

Sample Shown A-3109 & TS 574-01

Type of Sample Separator Sample


N2 0.005 C 13 0.006

CO2 0.822 C 14 0.005

H2S --- C15 0.004

CH4 97.718 C 16 0.003

C2 0.881 C 17 0.003

C3 0.115 C 18 0.002iC4 0.040 C 19 0.002

nC4 0.019 C 20 0.002

iC5 0.013 C 21 0.002

nC5 0.008 C 22 0.002

C6 0.026 C 23 0.001

MCP 0.002 C 24 0.001

Benzene 0.009 C 25 0.001

C7 0.164 C 26 0.001

Toluene 0.057 C 27 0.001

C8 0.035 C 28 0.001


m - Xylene 0.001 C 30 0.000

p - Xylene 0.005 C 31 0.000

o - Xylene 0.005 C 32 0.000

C9 0.014 C 33 0.000

C10 0.008 C 34 0.000

C11 0.006 C 35 0.000

C12 0.007 C 36+ 0.000



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Table 5-c – Summary PVT Data of Well NWK1-3

Sample Shown 2072

Type of Sample MDT Mathematical Recombined


N2 0.0596 C 13 0.2154

CO2 1.0067 C 14 0.0768

H2S ---- C15 0.0262

CH4 97.1175 C 16 0.0186

C2 0.9528 C 17 0.0060

C3 0.1279 C 18 0.0013iC4 0.0410 C 19 0.0010

nC4 0.0201 C 20 0.0009

iC5 0.0145 C 21 0.0014

nC5 0.0092 C 22 0.0006

C6 0.0218 C 23 0.0008

MCP 0.0015 C 24 0.0004

Benzene 0.0081 C 25 0.0003

C7 0.0963 C 26 0.0003

Toluene 0.0131 C 27 0.0002

C8 0.0494 C 28 0.0001


m - Xylene 0.0014 C 30 0.0001

p - Xylene 0.0068 C 31 0.0000

o - Xylene 0.0030 C 32 0.0001

C9 0.0065 C 33 0.0001

C10 0.0040 C 34 0.0001

C11 0.0193 C 35 0.0001

C12 0.0678 C 36+ 0.0001



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9- Communication Protocol:

It is essential that all commissioning parties communicate with one another during the fieldcommissioning activities. The primary contact will be control room to control room. Commissioningshall be done during daylight hours so optimum support is available to resolve issues that develop.

The below contact list is provided to assist in ensuring good communications is maintained.

Name Position Telephone Mobile FaxRadio RoomField GeneralManagerProductionGeneral ManagerProductionManagerProductionSpecialist

NWK Startup Procedure

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