Upload
ashrafsaber
View
38
Download
4
Embed Size (px)
Citation preview
BASIC PETROLEUM AND ESP Andi A Wibowo,
SBU Production Supervisor
BASIC PRODUCTION-ESP OPERATION
CONTENTS
HOW HYDROCARBON FORMED?HOW HYDROCARBON FORMED?
OIL FIELD RESERVOIR OIL FIELD RESERVOIR
RESERVOIR DRIVE MECHANISMRESERVOIR DRIVE MECHANISM
RESERVOIR CHARATERISTICRESERVOIR CHARATERISTIC
RESERVOIR PRESSURE PROFILERESERVOIR PRESSURE PROFILE
TYPICAL COMPLETION TYPETYPICAL COMPLETION TYPE
FORMATION PROBLEMFORMATION PROBLEM
SCALESCALE
BASIC ESPBASIC ESP
HOW HYDROCARBON FORMED?
I I I I I I I I I I I I I I I I I I I I I I
I I I I I I I I I I I I I I I I I I I I I I
I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I
I I I I I I I I I I I I I I I I I I I I I
DUST
DEAD FISH
TEMPERATURE
PRESSURE
SALINE
TEMPERATURE
TEMPERATURE
PRESSURETEMPERATURE
PRESSURETEMPERATURE
PRESSURE PRESSURETEMPERATURE5000 Ft – 21000 Ft5000 Ft – 21000 Ft5000 Ft – 21000 Ft5000 Ft – 21000 Ft
+3,000,000 Years
TRANSFORM TO HYDROCARBON
SEDIMENTATION
SE
DIM
EN
TA
TIO
N K
EE
PS
OC
CU
RIN
G O
VE
R T
IME
HOW HYDROCARBON FORMED??
Oil formed at 120°F- 350 °F, in 5,000 – 21,000 feet depth about 3,000,000 years ago (minimum).
• Gas formed at temperature > 350 °F, in 21000 feet depth in short period of time
• Due to smaller density, buoyancy forces and capillarity ,oil and gas move up through the area – this is called fluid migration
• Vertical migration for gas and oil sometimes possible to surface
• Horizontal migration less than 200 miles of distance
• Hydrocarbons are trapped and accumulate on the impermeable rock media which is common called Cap Rock
HOW HYDROCARBON FORMED??
TRAP
200 MILES
SURFACE
UNSEALED ROCK
SALINEIMPERMEABLE
ROCK
OIL RESERVOIR
MIGRATION
TRAPPED
HYDROCARBON
OILFIELD RESERVOIR
A petroleum reservoir must A petroleum reservoir must have three things:have three things:
- Source Rock for the Hydrocarbons
- Reservoir rock that is porous and permeable
- An Impermeable seal to trap the Hydrocarbon
• Reservoir rock generally sedimentary of sand stone or limestone (carbonate)
• Talang Akar formation is a sandstone and Baturaja formation is Carbonate
Pore space
Permeability
OILFIELD RESERVOIR
Productivity Index (PI) = Q / (SBHP-PBHP)Productivity Index (PI) = Q / (SBHP-PBHP)
PI PI Rate Rate So Bigger PI is better So Bigger PI is better
PI depends on : - drawdown (SBHP – PBHP)PI depends on : - drawdown (SBHP – PBHP)
- reservoir permeability (k) - reservoir permeability (k)
- Porosity- Porosity
How fluid goes to surface?How fluid goes to surface?
- Natural flow : if Reservoir pressure still high - Natural flow : if Reservoir pressure still high
- Artificial lift :if reservoir Pres has been depleted- Artificial lift :if reservoir Pres has been depleted
How about CNOOC ? “ Almost all wells using ESP as How about CNOOC ? “ Almost all wells using ESP as artificial lift”artificial lift”
RESERVOIR DRIVE MECHANISM
Water DriveWater Drive
Solution Gas DriveSolution Gas Drive
Gas- Cap expansion driveGas- Cap expansion drive
RESERVOIR CHARATERISTIC
Porosity : comparison between pore volume and Porosity : comparison between pore volume and bulk volume (space of formation rock)bulk volume (space of formation rock)
Permeability. Higher permeability is better reservoirPermeability. Higher permeability is better reservoir
Fluid Saturation, represent percent of pore volume Fluid Saturation, represent percent of pore volume that filled by fluidthat filled by fluid
Formation Volume Factor, represents the shrinkage Formation Volume Factor, represents the shrinkage of res.fluid volume when it at surface conditionof res.fluid volume when it at surface condition
o
oo
E.S.P.
PSI
SBHP *
PBHP *
Pressure
Distance
Qf
PI = PI = Qf . Qf .
(SBHP-PBHP)(SBHP-PBHP)
Near wellbore drawdown about 70%Near wellbore drawdown about 70%
SBHP* and PBHP* read with Surveyor UnitSBHP* and PBHP* read with Surveyor UnitFluid
Level
RESERVOIR PRESSURE PROFILE
WELL COMPLETION
FORMATION PROBLEMS
Pressure Depleted Pressure Depleted
‘ ‘The pressure is naturally depleted along with The pressure is naturally depleted along with oil producing’, Low reservoir pressure ==oil producing’, Low reservoir pressure == more difficult to lift up ==more difficult to lift up == need artificial lift. need artificial lift.
Formation problem / Inflow Problem Formation problem / Inflow Problem
- Scale Problem- Scale Problem
- Sand Problem- Sand Problem
SCALE PROBLEM
Scale is a mineral precipitation, It could be a problem Scale is a mineral precipitation, It could be a problem if in a big amount and plugging up reservoir pore if in a big amount and plugging up reservoir pore and pump.and pump.
Very common oil field scale : Very common oil field scale : calcite,barite,ironic,anhydrite,gypsum,etccalcite,barite,ironic,anhydrite,gypsum,etc
Why scale build up? The main cause is decreasing Why scale build up? The main cause is decreasing mineral (calcite, barite,etc ) solubility in the water by mineral (calcite, barite,etc ) solubility in the water by changing temperature and pressure.changing temperature and pressure.
Generally, The solubility will decreasing when P and Generally, The solubility will decreasing when P and T drop. T drop.
SCALE PROBLEM (CON’T)
Scale deposit in the impeller,diffuser and tubing
SCALE PROBLEM
Scale could lead to:Scale could lead to:
- Inflow problemInflow problem : scale could plugging up the : scale could plugging up the formation,perforation and pump intakeformation,perforation and pump intake
Indication : BHP rapidly decreasing, Running Indication : BHP rapidly decreasing, Running ampere drop and BHT increasing due to not enough ampere drop and BHT increasing due to not enough fluid cooling down the ESP motorfluid cooling down the ESP motor
- Pump stuckPump stuck = = Overload = Overload = DHP DHP
SCALE PROBLEM
What should be done?What should be done?
- Stimulation, If scale build up in formation.Stimulation, If scale build up in formation.
Stimulation is the process of injection acid into formation to remove Stimulation is the process of injection acid into formation to remove damage around wellbore.damage around wellbore.
- Pump clean up,If scale build up in pump.Pump clean up,If scale build up in pump.
Stimulation Process
Basic ESP
Basically ESP is a centrifugal pump with electric power Basically ESP is a centrifugal pump with electric power from surface.from surface.
ESP part : surveyor+ motor+ Protector+ Intake+ PumpESP part : surveyor+ motor+ Protector+ Intake+ Pump
ESP develops extra head (pressure) to lift fluid to surface. ESP develops extra head (pressure) to lift fluid to surface.
The pump sizing and design depends on PI,free gas ,sand The pump sizing and design depends on PI,free gas ,sand tendencies,depth,viscosity,etctendencies,depth,viscosity,etc
Each type of ESP has optimum operating range and Each type of ESP has optimum operating range and efficiency.efficiency.
ESP isn’t efficient for high free gas well ESP isn’t efficient for high free gas well gas lock gas lock problemproblem
ESP manufacture : ESP manufacture : REDA,Centrilift,ESP,ODI,Daqing,Shangli,etcREDA,Centrilift,ESP,ODI,Daqing,Shangli,etc
E le c tric M o to rE le c tric M o to r
Protector
Intake or Gas Separator
Centrifugal Pump
System Components of Typical Installation
The pump is seated above the perforations in such a way that the well fluid moves upward around the motor housing, cooling the motor by dissipating the heat generated.
All the components are connected together and hang from the tubing.
CableMLE and Power Cable
Basic ESP Components
Basic ESP EngineeringS
ch
lum
berg
er P
rivate
Flow
FlowFlow
Ground Level
Producing Fluid Level
Pump Set Depth
Wellhead
Net Vertical Lift1
2Total Friction Loss
Wellhead Pressure
3
Pump Operating Range
Efficiency
Pump Range
Head
HP per Stage
ESP Problems
How to identify problem? Simple….LOOK AMCHART. How to identify problem? Simple….LOOK AMCHART. Every single line tell us something.Every single line tell us something.
What is am chart?.What is am chart?.
- Electrical drive pump. - Electrical drive pump.
- Power consumed by motor depends on operating point ==>- Power consumed by motor depends on operating point ==>
pump curvespump curves
- Power consumed = f(running amps)- Power consumed = f(running amps)
- Running Amps ==> diagnose parameter- Running Amps ==> diagnose parameter
Commons Problem : Underload,Overload,Gas lock,Pump Commons Problem : Underload,Overload,Gas lock,Pump Off, lost flowOff, lost flow..
Underload Problem
Why it happen?Why it happen?
Not enough fluid Not enough fluid level, shaft brokenlevel, shaft broken
Troubleshooting:Troubleshooting:
Choke backChoke back
Reduce frequencyReduce frequency
Try to raise up fluid Try to raise up fluid level by bleed off level by bleed off casing pressurecasing pressure
605040302010
1
2
3
4
5
10
811
6 AM
NOON
12
3
4
5
6 PM
7
9
M I D N I G H T
Under-current Load
Overload Problem
Common causes:Common causes:
Increased fluid gravityIncreased fluid gravity
Sand productionSand production
Scale build upScale build up
Increasing viscosity Increasing viscosity (emulsion)(emulsion)
Electrical problemElectrical problem
DO NOT restart the DO NOT restart the pump before check pump before check cable and cleared cable and cleared problemproblem
605040302010
1
2
3
4
5
10
8
11
6 AM
NOON
12
3
4
5
6 PM
7
9
M I D N I G H T
Overload
Gas Lock
Why? A big free gas in pump.Why? A big free gas in pump.
What we can do:What we can do:
Choke back and raise up Choke back and raise up fluid level at annulus.fluid level at annulus.
Reduce frequency using VSDReduce frequency using VSD
Deepening the pump Deepening the pump
Install down hole gas Install down hole gas separator (VGSA + AGH)separator (VGSA + AGH)
605040302010
1
2
3
4
5
11
10
8
11
10
9
8
6 AM
NOON
12
3
4
5
6 PM
7
9
M I D N I G H T
Gas Locking
Pump hasgas locked
3