Transcript Pipeline Flow Assurance

Pipeline Flow Assurance
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Flow Assurance Introduction
Flow Assurance Problems
Production Chemicals Used
HCD Multi Flow Advantage
HCD Multi Flow Case Studies
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Pipeline Flow Assurance
• What is Flow Assurance?
• “Transporting the fluid from well to facility with low risk.”
• Flow assurance, also known as multiphase transport, involves the
transport of a mixture of oil, gas, condensates and water in the
same pipeline.
• It refers to ensuring successful and economical flow of hydrocarbon
stream from reservoir to the point of sale.
• Besides network modeling & transient multiphase simulation, flow
assurance involves effectively handling many solid deposits, such as,
gas hydrates, asphaltene, wax, scale and naphthenates.
• Flow Assurance is critical in every field development.
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Pipeline Flow Assurance
• Flow Assurance is now synonymous with wide range of issues, for
example:
• System Deliverability - pressure drop versus production, pipeline
size & pressure boosting.
• Thermal Behavior - temperature changes, insulation options &
heating requirements.
• Production Chemistry - hydrates, waxes, asphaltenes, scaling, sand,
corrosivity & rheology.
• Operability Characteristics - start-up, shut down, transient behavior
(e.g. slugging etc.).
• System Performance - mechanical integrity, equipment reliability,
system availability etc.
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Pipeline Flow Assurance
• More recently however, the Flow Assurance problems encountered
in oil and gas production have become more onerous, leading to an
increased overall awareness in the industry.
• This is particularly in the offshore sector, where low temperatures,
remote locations & often great water depths of subsea
environments conspire to exacerbate problems such ass
erosion/corrosion, blockages through hydrate formation or wax
deposition or topsides’ facilities shutdown due to severe slugging.
• Moreover, the ramifications of these issues can be serious incurring
significant intervention costs and substantial losses in production.
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Pipeline Flow Assurance
• Physical – Chemical Flow Obstruction
• Multiphase flow may be obstructed by physical phenomena such as
liquid slugs or surges, or by physical- chemical phenomena. Of the
latter four of the commonest are listed below:
• Asphaltenes- the heaviest components in the crude oils, which may
aggregate and precipitate in response to changes in chemical
composition, pressure or temperature. Precipitation or deposition
may occur in reservoir rocks, wellbores and pipelines.
• Wax- a natural constituent in most petroleum fluids, this may be
deposited on cold surfaces such as pipeline walls, increase the
viscosity of oil until it ultimately gels and settle out at the bottom of
storage tanks.
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Pipeline Flow Assurance
• Emulsions - water droplets in oil, which tend to be stabilized by
natural oil components and in the presence of certain solid
particles. As a result, they obstruct flow and complicate separation
of produced water from oil.
• Gas Hydrates – resembling snow balls or slush, these are crystalline
materials comprising a framework of water molecules with their
cavities filled by gas. Small clumps are easily carried along with flow
but large cohesive blocks can cause a partial or complete blockage.
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Pipeline Flow Assurance
• Scale in Oil Production Facilities
• Oilfield scale consists mainly of inorganic salts with calcium
carbonates, barium and strontium sulphates as the commonest
components.
• Scale can from brine (formation water) as it undergoes changes in
pressure and temperature, or where two incompatible fluids are
intermingled.
• Scale problems can arise in various circumstances:
 During drilling and well completion, if the drilling mud or
completion fluid is incompatible with the formation water.
 At the commissioning stage of new injectors, if the injection water
is incompatible with formation water.
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Pipeline Flow Assurance
 During production, when a well starts to produce formation water
with the hydrocarbons.
 During well stream processing, when significant quantities of
produced water put process equipment at risk.
 Commingled production, where wellstreams from various
formations, reservoirs or individual wells are mixed together, can
make matters worse.
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Pipeline Flow Assurance
Predicting
Problem
Solving
Flow
Assurance
Prevention
Monitoring
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Pipeline Flow Assurance
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Production Chemicals:
Pour Point Depressant
Paraffin Inhibitor/ Wax Inhibitor
Asphaltenes Dispersant
Hydrate Inhibitor
Scale Inhibitor
Drag Reducer
Defoamer/ Antifoam
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Pipeline Flow Assurance
• HCD MultiFlow (Pipeline Viscosity & Drag Reduction)
• HCD MultiFlow is a revolutionary conditions specific deposit
reliquification product designed specifically for oil transfer flow line
deposition.
• HCD MultiFlow was developed by HCD scientists and engineers to
liquefy and remove asphaltene and paraffin deposits in oil flow
lines.
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Pipeline Flow Assurance
• How It Works:
• The reliquification is accomplished by breaking down the chemical
bonds which exist between individual carbon chains and
substituting smaller carbon chains in their place carried by HCD
Multi-Flow.
• HCD Multi-Flow reliquifies the hydrocarbon chain in any deposits
on contact, reducing asphaltene and paraffin flow restrictions in the
transfer line.
• This reduction aids in reducing under deposit corrosion, increases
flow line size, increases flow rate and reduces sludge layers along
pipe walls.
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Pipeline Flow Assurance
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Applications:
Flow line “pigging” substitute
Continuous flow line injection
Oil flow lines from ships and ship to shore transfer lines
Oil flow lines to holding tanks.
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Benefits:
Rapid line clean-up
Removes the risk of a “stuck pig” incident
Reduce oil viscosity/ increase flow rate
Non-toxic
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Pipeline Flow Assurance
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Biodegradable
Raises API specific gravity and reduces viscosity
No hazardous product handling
Reduces heating or steam line requirements.
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Pipeline Flow Assurance
• The HCD Multi-Flow Additive introduces a carbon molecular blend
to produced fluids that prevents like molecular aggregation of
waxes, asphaltenes and resins.
• This mechanism allows HCD to provide a uniquely long lasting flow
assurance solution for pipeline and storage tank crudes.
• HCD is not a Polymer, Surfactant or a conventional Flow Improver HCD is a molecular Disaggregator.
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Pipeline Flow Assurance
• HCD attacks the root cause of the paraffin networking and
asphaltene aggregation by interrupting the like molecular forces
(London Forces) responsible for viscosity increase and solidificationfreeing the individual molecules from these structures – resulting in
liquefication and flow assurance.
• HCD achieves rapid in-line separation of the water and oil phases,
breaking emulsions and eliminating foam.
• HCD MULTIFLOW will also prevent deposition of Hydrocarbon solids
(sludge) on the flow line walls and in the cargo tanks.
• HCD MULTIFLOW will also prevent Hydrocarbon deposition on Heat
Exchangers, Hydro-Cyclones and other process equipment
vulnerable to wax and asphaltene deposition.
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Pipeline Flow Assurance
• HCD MultiFlow is a multi purpose additive – this single chemical
additive replaces the need for:
 Pour Point Depressants
 BS&W Control Additives
 De- Emulsifiers
 Anti- Foaming
 Anti- Waxing Agents (chemical ‘pigging’)
 Heating (Savings on Steam & Heat Exchanger Requirements)
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Pipeline Flow Assurance
• HCD MultiFlow has the following advantages over alternative
chemical additive regimes:
 High Flash point of 97°C so it stays in the produced crude.
 Hydrophobic non water based – so it does not contaminate the
water phase.
 Organic molecular blend (does not harm the crude or affect refinery
processes)
 Low toxicity (HSE)
 Low volatility (HSE)
 Easy to handle fluid
 Prevents under deposit corrosion.
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Pipeline Flow Assurance
• The International Board of Environmental Health and Safety, Inc
(IBOEHS) has awarded HCD Multi-Flow the Safety Product of the
Year.
• The HCD Multi-Flow was selected because it plays a vital role in
reducing the need for harmful chemical additives in the extraction
and transport of crude oil, as well as making oil production more
efficient. Furthermore, as HCD Multi-Flow is acknowledged for
being non-toxic and replacing chemicals that cause harmful
exposures to workers, their communities and the
environment. Chemicals that HCD replaces are highly toxic and they
include conventional flow assurance additives such as Benzene,
Toluene and Xylene blends (BTXs). HCD Multi-Flow also replaces
certain Polymer and Monomer technologies and Pour Point
Depressants – many of which are extremely toxic to the marine
environment and aquatic life.
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Pipeline Flow Assurance
• HCD CARBON CHEMISTRY VISCOSITY TREATMENT
- Souedie Field, Syria: HCD Flow Assurance, 2010
• Crude Oil Character
Paraffinic & Asphaltenic Heavy Oil – API 9 – 12
High Viscosity - 200,000 cps at 20°C
• Client
SPC (Syria Petroleum Company)
• Introduction: Transfer line Flow Assurance for Enhanced Oil
Recovery Elimination on Paraffin and Asphaltene based Viscosity
• Purpose: The purpose of the trial was to inject the HCD additive
into the flow transfer line at the well head in a way that adequately
mixes the chemical product with the high viscosity crude.
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Pipeline Flow Assurance
• Results: Results were measured in terms of resistance in the line,
Flow rate at the Gathering Station and sample readings for wax and
asphaltene were taken from the valve at the end of the 5km
pipeline run.
• The well produces at a rate of 10m³ of liquid per day with a water
cut of 20%. The API gravity of this crude is 9.0 to 12.0 (well data
records)
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Pipeline Flow Assurance
DAY
Feed Rate
PPM
Oil only
(on 8m3
o/w)
Pressure
ATMs
Flow Rate
Increase
from 10 m3
(wc 20%)
(oc 80%)
Paraffins
as %
Asphaltenes
as %
Control
Sep 27th
2010
28.09.10
29.09.10
30.09.10
01.10.10
02.10.10
03.10.10
04.10.10
05.10.10
06.10.10
07.10.10
08.10.10
09.10.10
10.10.10
11.10.10
12.10.10
13.10.10
14.10.10
15.10.10
16.10.10
17.10.10
0
200 ppm
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+0%
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3.75
200ppm
200ppm
200ppm
250ppm
250ppm
250ppm
450ppm
450ppm
450ppm
600ppm
600ppm
750ppm
750ppm
250ppm
240ppm
240ppm
240ppm
0
0
0
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20
18-19
16
11
9.4
9.0
8.2
8.0
7
5
3.8
2
3
6
6.5
6.4
7.2
9.0
9.8
-15%
-10%
+12%
+18%
+30%
+37%
+54%
+72%
+70%
+89%
+97%
+98%
+102%
+96%
+80%
+65%
+71%
+40%
+42%
+37%
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22
22
22
15
10.5
9
7
6
5
3
3
2
5
6
5
6
12
18
22
4
4.5
4
3.2
3.7
2
1.7
1.5
1.2
1.1
0.8
0.8
0.5
0.55
0.95
1.1
1.35
2.1
3.2
3.75
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Pipeline Flow Assurance
• Summary of Results:
• The HCD Molecular blend worked on the heavy paraffinic and
asphaltic crude:
• An initial drop in flow rates was due to the deposition on the walls
of the pipeline being freed into suspension.
• After three days pipeline flow size and flow rate had increased.
• Even at temperatures averaging 12 deg C – some 53 degrees below
the Pour Point - the additive reduced wax levels and ensured flow.
• Asphaltenes were reduced with similar effectiveness
• An API lift was observable in the treated crude from 11 to around
13.7 (600ppm) and around 15.2 (1000ppm)
• Optimal cost effectiveness seemed to recommend dosages of
around 600 PPM
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Pipeline Flow Assurance
• HCD PPE - Trial of HCD MultiFLow (PPE) for wax, asphaltene, BS&W
control at Puteri platform and pipeline (PMO)
• Puteri Crude has a very high pour point due to its high wax content.
Pour point of Puteri crude – 47 – 49 °C
• Client: NEWFIELD (NFX)
PETRONAS CARIGALI SDN BHD (PCSB – PMO)
• Site:
Oil wells (from -1300m to Well Head) and 14 km long Pipeline
from Puteri Platform to BUK FPSO (PMO)
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Pipeline Flow Assurance
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Pipeline Flow Assurance
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Pipeline Flow Assurance
Observations & Key Findings:
• Flow Assurance:
• HCD Multi-Flow outperformed Roemex at the same dosages.
• Injection at the chemical mandrels proved to be very advantageous
– optimizing the mixing of the HCD PPE additive.
• The additional injection at the well-head made some impact but
lacked the mixing the chemical mandrel injection points offer.
• At higher dosages the Pour Point and the Remelt Temperature
seemed to diverge. This may be partly due to the testing conditions
and slower heating would provide more accurate analysis.
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Pipeline Flow Assurance
• The thermodynamics of Puteri crude need to be assessed and
applied to the analysis of the cooling times between different
temperatures. For example, it may take longer to cool from 34 deg
C to 32 deg C than it does from 36 deg C to 34 deg C. This will have
strategic significance for the 3rd mode of production.
• These results are on the co-mingled (Penara & Puteri) crude. If HCD
PPE was being injected at both Platforms the Pour Point Readings at
the Turret would be lower
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Pipeline Flow Assurance
• BS&W:
• The effect of HCD Multi-Flow on the Shake-Out tests – freeing the
trapped water as the crude rises has major economic benefits.
• The effect of HCD Multi-Flow in reducing BS&W readings after the
third separator on the FPSO (by 3.5 times) has major economic
implications, particularly in view of:
• A) discounts incurred for off-spec crude.
• B) Savings on the FPSO Water Separation Line (Savings on
Surfactants; Demulsifiers; and Time & Energy)
• These results are on the co-mingled (Penara & Puteri) crude. If HCD
PPE was being injected at both Platforms the
• BS&W readings could be on-spec even before the crude is
processed at BUK FPSO
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