water flood oil production

1. Problem Solving :
Water Flood for Oil Production
GROUP 11
ALIF NUZULUL HIDAYAT (1206249832)
DIDIK SUDARSONO (1206242555)
ENI MULYATININGSIH (1206201971)
RAHGANDA (1206261182)
SYLVIA AMANDA S (1206241230)

2. OUTLINE
INTRODUCTION
(Background, Project Objective, Plant Condition, Basic Theory)
PROCESS SYNTHESIS
(Alternative Process, Process Selection, Process Description, BFD, PFD)
MASS AND ENERGY BALANCE
(Mass Balance, Energy Balance, Simulation)

3. INTRODUCTION - BACKGROUND
• Reservoir pressure in Kerisi has started to decline  Enhanced Oil Recovery
(EOR) will be conducted to lift the remaining oil in the well.
• Based on studies by ConocoPhillips, EOR method chosen for Kerisi field is
waterflood.
• Waterflood will be done by injecting seawater taken from well K-14 to K-13
well.
• Oil and gas reservoir that will be injected by seawater contains no H2S gas
• Waterflood by injecting seawater into the formation will lower the
temperature of the reservoir to a temperature level that is conducive to the
SRB activity

4. INTRODUCTION - BACKGROUND
• Two methods of seawater pre-treatment to be considered today are sulphate
removal membrane and nitrate injection.
• The selection is not only based on its ability to reduce H2S in the product, but
also considering the limited space available on the platform and also the cost
required to install the pre-treatment facility.

5. INTRODUCTION – PROJECT OBJECTIVE
• To make a preliminary design of a seawater treatment plant to meet the
specifications of seawater injected into the well K-13 in order to
perform the waterflood to reservoir.
• To choose the most appropriate method to avoid the formation of H2S
by SRB which are the main problem that can occur due to the
waterflood
• To estimate the cost required to install the process facilities which are
needed for seawater treatment

6. INTRODUCTION – PLANT CONDITION

7. INTRODUCTION – PLANT CONDITION

8. INTRODUCTION – PLANT CONDITION
Component Concentration in raw seawater
K1+, mg/l 293
Na1+, mg/l 10493
Mg2+, mg/l 1150
Ca2+, mg/l 351.1
Cl1-, mg/l 18387
SO4
2-, mg/l 2671
HCO3
1-, mg/l 93
TDS, mg/l 33458
pH 8.3
TSS, mg/l 15-20
Temp., °C 20
Oxygen, mg/l 5-8

9. INTRODUCTION – BASIC THEORY

10. INTRODUCTION – BASIC THEORY

11. INTRODUCTION – BASIC THEORY
Mechanism of Sulfate
Reducing Bacteria (SRB)
Dissimilatory sulfate reduction occurs in
three steps:
• Conversion (activation) of sulfate to
Adenosine 5’-phosphosulfate (APS)
• Reduction of APS to sulfite
• Reduction of sulfite to sulfide

12. PROCESS SYNTHESIS
Basic Mechanism
Alternative Process :
• Sulfate Removal Membrane
• Nitrate Injection

13. PROCESS SYNTHESIS - SULFATE REMOVAL MEMBRANE
• Objective: reduce sulphate as main food supply for SRB

14. PROCESS SYNTHESIS - SULFATE REMOVAL MEMBRANE
• The process for removing sulfate ions from seawater is based on nano-
filtration (NF) membrane separation.
• NF is a membrane process that selectively removes sulfate ions to produce
seawater with low concentration sulphate (20-40 ppm).

15. PROCESS SYNTHESIS - SULFATE REMOVAL MEMBRANE
Advantages Disadvantages
• High quality injection ion sulphate from
water
• Reduction in need for biocides
• Reduction of scaling
• More effective squeeze treatments
• Assists control of bacterial (sulphate
reducing bacteria) well souring
• Lower operating costs and increases
productivity
• Degrade very quickly upon exposure to
free chlorine
• Use of DBNPA or equivalent biocide be
considered to prevent biological
fouling.
• Must add anti-scale to prevent calcium
scaling.
• Need high CAPEX to buy the sulphate
removal membrane.
• < 40 mg/L ion sulphate CAPEX is
$20MM USD
• < 30 mg/L ion sulphate incremental
CAPEX $103,000 USD; need higher
spec membrane.

16. PROCESS SYNTHESIS – NITRATE INJECTION
Facilities Process
1. Added NaOCl in order
2. Passing through course filter (range
50 - 2000 μm.
3. Passing through Multimedia filter
(<40 micron)
4. Oxygen Scavenger or de-aeration
5. Injection of chemical compounds:
• Nitrate
• Biocide
• Corrosion inhibitor
• Objective : bio-competition, to reduce
food supply for SRB

17. PROCESS SYNTHESIS – NITRATE INJECTION
Advantages Disadvantages
• Cheap nitrate price, around 30 US
Dollar per ton to get 45% of Ca(NO3)2.
• Can clean soured reservoir with
gradually injection up to 100 ppm
nitrate ion to facilities.
• Simple usage,
• Safe to use, not caused damage to
environment and potential for
microbial EOR.
• Water treatment facilities need to be
constructed with non-iron material.
• Reservoir performance can be lower as
there is permeability reduction to
bacterial colonies in critical flow
passages.
• There are no significant dosage of
nitrate for injection and also every well
will has different dosage depend on
condition

18. PROCESS SYNTHESIS – PROCESS SELECTION
Rating
Criteria
Performance to
Prevent H2S
Production
Space Required
Corrosion Effect
to Sub-Surface
Facilities
Easy to Operate
Investment
Cost
Environment
Effect
Weight
(%)
30 25 15 10 15 5
1
More than 600 ppm
H2S concentration in
10 year
Require very large
spacing ( > 4000
m2), so must
require expansion
platform
Contain corrodent
(O2, acid, bacteria)
and electrolyte
with high
concentration
Cannot operate
automatic, always change
parameter of
composition in chemical
injection and often
maintenance
More than
$40 million
Very dangerous
for environment,
chemical
injection is
strongly
hazardous and
explosive
2
600 ppm-300 ppm
H2S concentration in
10 year
Require large
spacing (4000 -
3000 m2), so must
require expansion
platform
Contain corrodent
(O2, acid, bacteria)
with low
concentration and
electrolyte with
high concentration
Cannot operate
automatic, sometime
change parameter of
composition in chemical
injection and often
maintenance
$40 million -
$30 million
Dangerous for
environment,
chemical
injection is
strongly
hazardous
3
300 ppm -100 ppm
H2S concentration in
10 year
Require middle
spacing (3000-
2000 m2), so must
require expansion
platform
Contain corrodent
(O2, acid, bacteria)
and electrolyte
with low
concentration
Cannot operate
automatic, sometime
change parameter of
composition in chemical
injection and seldom
maintenance
$30 million -
$20 million
Less dangerous
for environment,
chemical
injection is bit
hazardous

19. PROCESS SYNTHESIS – PROCESS SELECTION
Rating
Criteria
Performance to
Prevent H2S
Production
Space Required
Corrosion Effect
to Sub-Surface
Facilities
Easy to Operate
Investment
Cost
Environment
Effect
Weight
(%)
30 25 15 10 15 5
4
100 ppm -50 ppm
H2S concentration
in 10 year
Require narrow
spacing (2000-
1000 m2), not
require
expansion
platform
Not contain
corrodent (O2,
acid, bacteria),
but contain
electrolyte
Can operate
automatic, sometime
change parameter of
composition in
chemical injection and
seldom maintenance
$20 milion -
$10 milion
No-negative
environmental
. chemical
injection is
less hazardous
5
Less than 50 ppm
H2S concentration
in 10 year
Require very
narrow spacing
(< 1000 m2), not
require
expansion
platform
Not contain
corrodent (O2,
acid, bacteria)
and electrolyte
Can operate
automatic, seldom
change parameter of
composition in
chemical injection and
seldom maintenance
Less than
$10 milion
No-negative
environmental
. chemical
injection is not
hazardous

20. PROCESS SYNTHESIS – PROCESS SELECTION
Parameter
Weight
(%)
Sulphate
Removal
Membran
Weight
Score
Nitrate
Injection
Weight
Score
Performance to
prevent H2S
production
30 5 1.5 4 1.2
Space required 25 2 0.5 4 1
Prevent corrosion
on sub-surface
Facilities
15 4 0.6 2 0.3
Investment Cost 15 2 0.3 4 0.6
Ease to Operate 10 2 0.2 4 0.4
Environment
Effect
5 4 0.2 5 0.25
Total 100 3.3 3.75

21. PROCESS SYNTHESIS - BLOCK FLOW DIAGRAM
Figure 2.17. Vacuum Stripping De-aeration

22. PROCESS SYNTHESIS - PROCESS DESCRIPTION
Capacity waterflood : 50.000 barrel or
339000 kg/h
Capacity seawater : 741000 kg/h
Waterflood Characteristic

23. PROCESS SYNTHESIS - PROCESS DESCRIPTION
1. Pre-Primary Filtration
• Basin is a reservoir of seawater to
be pumped.
• Basin serves to prevent floating dirt
is not carried into seawater lift
pump.
• A deeper intake is aim to get sea-
water that contain low TSS, low
oxygen, low temperature and
consistent water quality
• In basin, seawater is injected
sodium hypochlorite (𝑁𝑎𝑂𝐶𝑙) that
is produced in hypochlorite
generator.
Figure 2. 8. Basin Structure for Pre-Primary Filtration

24. PROCESS SYNTHESIS - PROCESS DESCRIPTION
1. Pre-Primary Filtration
• Raw material : Seawater
• Process : Electrolysis (In Situ)
Anode : 2𝐶𝑙−
→ 𝐶𝑙2 + 2𝑒−
Cathode : 2𝑁𝑎+
+ 2𝐻2 𝑂 + 2𝑒−
+
𝐶𝑙2 → 2𝑁𝑎𝑂𝐶𝑙 + 2𝐻2
Overall : 𝑁𝑎𝐶𝑙 + 𝐻2 𝑂 → 𝑁𝑎𝑂𝐶𝑙 + 𝐻2
Figure 2. 9. Hypochlorite Generator

25. PROCESS SYNTHESIS - PROCESS DESCRIPTION
2. Primary Solid Removal
• Remove suspended solid (> 100 µm) with
98% efficiency.
• Type : Dead End Filtration
• Flow capacity up to 2270 GPM (619 m3/h)
• If pressure drop is high, flush process start
to clean the solid that is restrained.
• Flush process can operate automatic.
Raw Water Inlet Filtered Water Outlet
Sludge Outlet
Figure 2.10. Coarse Strainer Unit

26. PROCESS SYNTHESIS - PROCESS DESCRIPTION
3. Secondary Solid Removal
• Remove suspended solid (> 2 µm) with
98% efficiency. (high turbidity in seawater)
• Type : Granular Filtration
• Flow capacity up to 425 m3/h
• Backwash : Clean the bed, High pressure
drop
• The ideal backwash rate is 250-450 m3/h.
Figure 2.11. Multi Media Unit
Raw Water Inlet
Filtered Water Outlet
Sludge Outlet
Backwash Inlet
Anthracite
Fine Garnet
Coarse Garnet

27. PROCESS SYNTHESIS - PROCESS DESCRIPTION
4. De-aeration
• Remove oxygen in seawater (< 50 ppb)
• Type : Vacuum Stripping De-aeration
• Equipment : De-oxygenation tower, Ejector,
Vacuum Pump, Separator.
• Principle :
o Partial pressure of oxygen in water is a
function of the total pressure of the system.
o Vacuum the system can reduce the partial
pressure of oxygen and make driving force for
mass transfer of oxygen from the liquid to the
gas phase.
Figure 2.17. Vacuum Stripping De-aeration

28. PROCESS SYNTHESIS - PROCESS DESCRIPTION
6. Chemical Injection Package
Chemical Dosage Treatment Application Injection Point
Scale Inhibitor 20 ppm First, 200.000
bbls of water
injection
Inhibits CaCO3 scale Discharge
seawater lift
pump
Calcium Nitrate 100 ppm Continuous Microbial control by
bio-competition
Suction of water
injection pump
Biocide THPS 200 ppm Batch, Once a
week for 4
hours
Microbial control Suction of water
injection pump
Oxygen Scavenger 10 ppm Continuous, Reduce oxygen to low
concentration
Exit of de-aerator
Corrosion Inhibitor 30 ppm Continuous, To prevent corrosion
in subsurface
facilities
Suction of water
injection pump

29. PROCESS SYNTHESIS - PROCESS FLOW DIAGRAM

30. PROCESS SYNTHESIS - PROCESS FLOW DIAGRAM
Streams
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Mass Flow Rate
(kg/h)
741,523 741,498 88,979 24.22 339,309 339,308 33,058 33,060 339,305 2.66 339,305 4.79 40.48 1.79 32.41 339,384 339,384
Pressure (bar) 7.10 7.01 7.01 7 7.01 7.01 1.01 1.01 7.10 7.10 17.01 1.01 1.01 1.01 1.01 1.01 125.01
Temperature (C ) 25.06 25.06 25.06 25.10 25.06 25.06 25.00 25.00 25.06 25.06 25.10 25.00 25.00 25.00 25.00 25.10 25.63
Alga (% mass) 0.0005 0.0005 0.0005 0.0003 0.0005 0.0000 - 0.0049 0.0000 - 0.0000 - - - - 0 0
Solid (% mass) 0.0015 0.0000 0.0000 10.9000 0.0000 0.0000 - 0.0003 0.0000 - 0.0000 - - - - 0 0
TDS (% mass) 3.25 3.25 3.25 0.43 3.25 3.25 3.25 3.25 3.25 - 3.25 - - - - 3.24 3.24
NaOCl (% mass) 0.00001
0.00000
1
0.000001 0.000001 0.000001 0.00000 - - 0.00000 - 0.00000 - - - - 0 0
Oxygen (% mass) 0.0008 0.0008 0.0008 0.0000 0.0008 0.0008 0.0008 0.0008 0.0000 100.00 0.0000 - - - - 0 0
Water (% mass) 96.74 96.74 96.74 53.21 96.74 96.74 96.74 96.74 96.74 - 96.74 - - - - 96.74 96.74
Na2SO3 (%mass) - - - - - - - - - - - 40 - - - 0.0006 0.0006
Water (% mass) - - - - - - - - - - - 60 - - - - -
Ca(NO3)2
(% mass)
- - - - - - - - - - - - 45 - - 0.0054 0.0054
Water (% mass) - - - - - - - - - - - - 55 - - - -
THPS (% mass) - - - - - - - - - - - - - 50 - 0.0003 0.0003
Water (% massa) - - - - - - - - - - - - - 50 - - -
Cyclo-hexylamine
(% mass)
- - - - - - - - - - - - - - 13 0.0012 0.0012
Morpholin
(% mass)
- - - - - - - - - - - - - - 7 0.0007 0.0007
Water (% mass) - - - - - - - - - - - - - - 80 - -

31. PROCESS SYNTHESIS - PROCESS FLOW DIAGRAM

32. MASS AND ENERGY BALANCE – MASS BALANCE
Mass Balance Inlet for Overall Processes
Inlet Stream
Mass Flow
(kg/hr)
Inlet Component
Mass Flow
(kg/hr)
Seawater (Feed) 741,522.87
H2O 717,402.61
Oxygen 5.93
Dissolved Solid 24,099.49
Suspended Solid 14.83
NaOCl 18 0.23 NaOCl 0.23
Chemical Injection
Package
12
79.47
Oxygen Scavenging
Chemical
4.79
Calcium Nitrate
Solution
40.4813
Biocide Solution 1.7914
15 Corrosion Inhibitor 32.41
Total 741,602.57
(Source: Author’s personal data)

33. MASS AND ENERGY BALANCE – MASS BALANCE
Mass Balance Outlet for Overall Processes
(Source: Author’s personal data)
Outlet Stream
Mass Flow
(kg/hr)
Outlet Components
Mass Flow
(kg/hr)
Injected
Seawater
16 339,384.98
H2O 328,329.49
Oxygen 0.05
Dissolved Solid 11,055.34
Suspended Solid 0.09
Oxygen 10 2.66 Oxygen 2.66
Utility
Water
3 88,979.86
H2O 86,086.77
Oxygen 0.71
Dissolved Solid 2,891.91
Suspended Solid 0.47
Disposed
Seawater
313,235.06
H2O 303,038.31
4 and 8 Oxygen 2.51
Dissolved Solid 10,179.97
Suspended Solid 14.27
Total 741,602.56

34. MASS AND ENERGY BALANCE – ENERGY BALANCE
(Source: Author’s personal data)
[Energy In] – [Energy Out] = [Accumulation of energy]
∆𝐸 = 𝑚𝑖 𝐻 + 𝐸𝑘 + 𝐸𝑝 − 𝑚𝑜 𝐻 + 𝐸𝑘 + 𝐸𝑝 − 𝑄 + 𝑊
Inlet Stream
Heat Flow
(MJ/h)
Outlet Stream
Heat Flow
(MJ/h)
Seawater 77,423.15 Injected Seawater 17 36,322.63
NaOCl 18 0.01 Oxygen 10 0.06
Pump 1 191.16 Backwash 8 32,783.85
Pump 2 60.19 Utility Water 3 9,313.59
Oxygen
Scavanging
Chemical
12 0.36
Calcium Nitrate 13 2.63
Biocide 14 0.38
Corrosion
Inhibitor
15 2.99
Total 78,427.17 Total 78,421.69
Pump 3 746.28 Sludge 4 1.56

35. MASS AND ENERGY BALANCE – ENERGY BALANCE
Mass Efficiency
Energy Efficiency

36. NEED FOR MASS AND ENERGY
To produce 50,000 BWPD for
waterflood, it needs
108,667 barrels water per day in the
feed, and
3 pumps with total power 1669 kW

37. MASS AND ENERGY BALANCE – SIMULATION
• Using SuperPro

38. CONCLUSION
1. Process of Enhanced Oil Recovery (EOR) will be conducted to lift the remaining oil
from Kerisi well with water flood method.
2. Design for the process need to meet criteria such as reduce amount of content
that may cause problem in well like TSS, sulphate ion, and oxygen from seawater,
facilities can be placed on available area and should be as economical as possible.
3. Parameters that will be used in process selection are performance to prevent H2S
production, space limited, corrosion effect, investment cost and environment.
4. Process selected for seawater for injection well is nitrate injection process which is
used calcium nitrate with concentration 100 ppm to process water.
5. There are several main section of this plant as follow pre-primary filtration,
primary solid removal with coarse strainer, secondary solid removal with
multimedia filter, de-aeration and chemical injection package.
6. We simulate the overall process using SuperPro Software and processing the data
to calculate mass and energy balance. It needs 108,667 barrels water per day or
equivalent to 741,522 kg/h to produce 50,000 barrels water per day to fullfill
demand of waterfloods in the oil well. For energy needs, we will have three pumps
with total power 1669 kW.

39. Injection of 50,000 bpd of seawater will lik
ely increase the H2S level in the productio
n system to around 600 ppmv
in 10 years. The increase of H2S is caused
by several factors:
 Decrease in Reservoir temperature
over time.
 High (dissolved organic carbons)
 DOC in produced water.
 High Sulphate in the Seawater.
 Bacteria availability from the
seawater.

40. THANK YOU