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1. Project Title
Prevention and treatment of wax deposition within the
production string in Amal Oil Field (Case study)
Prepared by:
AAAAAAAAAAAAAAAAAAA (253171092)
BBBBBBBBBBBBBBBBBBB (253191056)
Supervised By: Ibrahim Yaquob
National Board for Technical & Vocational Education
College for Energy Technologies - Jikharra
Department of Oil and Gas Technology

2. Introduction
Problem statement
Objectives
Literature review
Methodology
Case Study
Conclusion & Recommendation

3. Introduction
Wax definition
Wax is alkanes , long chain compounds which separate out of oil when
the temperature drops below wax appearance temperature (WAT).
Wax formation consequences along
production string
 Flow restriction.
 Applying more pressure against formation.
 Production loss.
 Minimizing profitability.

4. Introduction
Problem of statement
Statement for this work In Amal Oil Field operated by
Harouge Oil Operations, wax formation and deposition
occur as a result of depressurization along the
production path. This pressure reduction makes the oil
expand, and results in heat would be drawn from the oil.
The temperature loss induces crystallization of the wax
and the subsequent deposition and accumulation along
of the tubing. It makes flowing more difficult due to
increasing viscosity and reducing the tubing inside
diameter. If the accumulation continues, wax deposition
leads to the decrease of well flow rates and eventually
causes total blockage.

5. Introduction
Project objective
The project aim is to
 Discuss the reasons behind wax appearance.
 See how appearance leads to reduction in production rate.
 Review the operational issues accompanied with wax appearance.
 Discuss and compare the different ways implemented in preventing its formation.
 Present real cases of two wells in Amal field that have suffered from forming wax.

6. Literature Review
The wax deposition in the positions adjoining the bore, the bore face, the
production string and the pump is caused by the cooling effect, that take
place when the produced oil flows from the high-pressure reservoir into
the wellbore to the surface.
In Amal Oil Field operated by Harouge Oil Operations, wax formation and
deposition occur as a result of depressurization along the production path.

7. Literature Review
Artificial lift importance
Increase production and enables dead
wells to produce.
Artificial lift forms
Gas lift.
Sucker rod pump.
Electrical submersible pump.
Hydraulic pumps.
Progressive cavity pump.

8. Wax prevention and removal
Wax precipitation detection methods
 Pressure drop method.
 Heat transfer method.
 Pressure wave propagation
method.
Pressure recorder (WHP/CSG P) Pressure monitoring table

9. Wax prevention and removal
Wax precipitation detection methods
(WHP/CSG P), before wax formation
(WHP/CSG P), after wax formation

10. Wax prevention and removal
Wax prevention techniques
Prevention implies preventing wax emerging within the top of the production string or
delaying its appearance until reaching the Flowline where it is easier to be tackled and
treated compared to downhole.
Avoiding occurrence the wax formation might be better than dealing with it. This is
because, delaying in running gauge cutter makes situation worse especially during
winter time as there is a possibility of having the tool string stuck.

11. Wax prevention and removal
Insulator material technique
When wax deposition prevention depends on keeping the flow temperature
above WAT, either with or without downhole heating, insulating the tubing
becomes a necessity. One particular case occurs when insulation materials
are installed in contact with the flow. In such cases, the selected material
can provide insulation and coating, yielding a double action against wax
deposition.

12. Wax prevention and removal
Heating techniques
Electric bottom-hole heaters are designed
to deliver controlled amounts of heat
energy using externally controlled power
cables. Although electric bottom-hole
heaters offer several operating advantages
that could not be obtained with other
heating methods, some serious
disadvantages have been experienced in
site conditions. Electrical cable helically placed around the tubing

13. Wax prevention and removal
Injecting chemicals.
It includes injecting wax crystal
modifier down tubing/casing
annuls via gas line. It prevents
wax from formation and
accumulation
Chemical
Gas inlet injection
Tubing
Reservoir
Production
oulet
Tubing/casing annulus
13

14. Wax prevention and removal
Mechanical method
It includes removing the formed wax
on two weeks basis or once a month.
Gauge cutter is run by slickline unit.
The well should be on to avoid
getting the tools stuck.
14

15. Wax prevention and removal
Wax removal technique
Tool Function
Rope socket Connects slickline to tool string
Knuckle joint Provides flexibility to positioning and orientation
Stem bar Adds weight to the tool sting for overcoming friction and provides
enough jarring impact downhole
Mechanical jar Creates jarring for applying hammer downward and upward
Gauge cutter Cuts and scrapes the deposited wax
Subsurface equipment
15

16. Wax prevention and removal
Wax removal technique
Surface equipment
surface equipment are
1-Slick line unit.
2- crane or gin pole.
3-Lubricator.
4-BOP.
5-Lower/upper sheaves.
6-Weight indicator.
7-Stuffing box. 16

17. Well Performance
Production system
 Porous media.
 Sand face.
 Wellbore.
 WEG.
 Production string.
 Landing nipples.
 Choke.
 Flowline.
 Surface production facility.

18. It is a systematic method implemented for
optimizing oil wells, which has been in use
to evaluate the whole production system. All
components within the production system
can be optimized to accomplish the mission
of producing in an economic manner.
 Determination the flow rate of a well.
 Predicting when well cease flowing naturally
Predicting.
 Selection of the most suitable conduit size.
 Assisting in artificial lift design.
Well Performance
Nodal analysis
Goals of nodal analysis
18

19. Wax deposition
Wax deposition mechanism
Low PI Low rate/ zero WC More temp loss
Gas cooling effect Wax appearance
X-01 and X-02 Case studies
 Low rate equipped with 2-7/8” tubing
 Zero WC

20. Wax deposition
X-01
 Low rate GL producer.
 Zero WC.
 Injected gas decreases
flowing temp.
 WAT 83 Deg F
P/T drop along production path

21. Wax deposition X-01
Well influx
Well schematic

22. Wax deposition
X-02
 Low rate GL producer.
 Zero WC.
 Injected gas decreases
flowing temp.
 WAT 85 Deg F
P/T drop along production path

23. Wax deposition X-02
QL,BOPD Pwf,Psia Pr,Psia
257 551 3200
Well influx
Well schematic

24. Wax deposition
Oil Production path
It is known that the oil
production journey takes place
from the drainage area of each
well towards the wellbore
(inflow within the reservoir) in
which only pressure drop is seen
while temperature remains
constant.

25. Wax deposition
Wax precipitation impact
 Once it forms it
restricts fluid flow
leading to more
pressure drop and
casing higher Pwf and
less production.
Production drop caused by wax formation and deposition

26. Wax deposition
Wax precipitation impact
 As differential pressure across
the orifice increases as a result
of increasing tubing pressure
below the formed wax interval,
the casing pressure increases
leading to opening unloading
valves (flow instability)

27. Conclusion
Wax deposition is a common worldwide issue in the oil industry
that occurs within the reservoir, production string, Flowline and
surface treatment plan. Besides lowering the production rate
leading to lower cash flow it causes operational issues such as
back pressure and instability in vessels working pressures. In
order to avoid these circumstances, prevention and remedial
approaches have been widely utilized.

28. Recommendations
 A comprehensive study should be made to oil properties with changing reservoir conditions to
check the reliability of wax treatment chemicals.
 Implementing a different artificial lift could eliminate the issue severity as no gas would be
injected.
 Avoiding wax deposition by treatment is better than removing it using the mechanical method to
avoid getting stuck.
 Conditions leading to wax appearance should be addressed for avoiding deposition.
 Approaches of wax tackling must addressed and compared in order to choose the best and most
efficient one with paying attention to cost.