Design of an Extraction Unit for Salt Water Removal from CrudeOil

1
Design of an Extraction Unit for Salt Water
Removal from Crude-Oil
United Arab Emirates University Faculty of
Engineering Chemical Engineering Department
CHME 2-4
Advisor Dr. Mamdouh Ghannam
Coordinator Dr. Jamaal Abou-Kassem
2
Contents

• Chemical Treatment.
• Point of Application.
• Methods of Application.
• Chemical feed pumps.
• Experiments
• Three phase separator Design.
• Piping Instrumentation Diagram.
• HAZOP Study.
• Indirect Heater Design..
• Environmental Impact.

3
Continue Content

• Experimental Design
• Material of Construction.
• Cost.

4
Chemical Treatment

• The main idea of this treating is to add some
  small amounts of surface active emulsion
  breaking chemicals (reagents ) into the treated
  emulsion to deactivate the water in oil (oil
  soluble reagent )
• After this treating the free phases separated by
  gravity exit the vessel

5

•  1) Point of Application of Chemicals
• The agitation takes place when the chemicals are
  sufficient for emulsion breaking .
• The chemical injection pump is usually placed at
  the header of the separator .

6

• 2) Relationship of Chemicals to Temperature
• In General the increasing of the
• emulsions temperature decreases the
• amount of chemicals required for its
• treating

7
 3) Relation of the amount of chemical to
settling time

• The amount and the type of chemicals define how
  the emulsion will break out, Sometimes , in
  chemical treatment , to fasten the break down
  process of emulsions
• 1-     Faster acting chemical can be used
• 2-     The temperature of the emulsion can be
  increased

8
(No Transcript)
9
Methods of Applying Chemicals

• The chemical compounds for chemical treating ,
  usually are put into the produced emulsion at any
  point in the system .
• Depending on the point of the application
  (injection or adding ) of the compounds there are
  three basic types of application in chemical
  treating of oil
• 1- Down hole treating.
• 2- Flow line treating.
• 3- Batch treating.

10
1) Down hole treating

• Emulsion becomes more viscous when it contains
  water dispersed in oil by agitation. This makes
  emulsion resist the flow in the system.
• Applying chemical treating down hole breaks the
  emulsion and makes it easier to lift.

11
2) Flow line Treating

• In this treatment the chemical reagent should be
• injected in flow line at a point where
  sufficient
• agitation and treating time are assured, usually
  this point is at the well head or at the header
  in multiple well systems.

12
(No Transcript)
13
3) Batch treating

• The produced emulsion from the well moves to the
  treating tank with heaters , where the chemical
  reagent drips slowly through the holes of a
  bucket into the emulsion to de-emulsify it.
  After settling the water will be drain off .
• This treating requires more chemical regents.   
   

14
(No Transcript)
15
Demulsifiers

• Quality Indexes are made with the most advanced
  ethoxylation catalytic polymerization technology
  developed.
• Packing Packed in 200kg galvanized drum or
  iron drum.
• Storage and Transportation nonpoisonous and can
  be dealt with as common chemicals and storage
  time is one year.

16
Chemical Feed Pumps

• Injecting chemical reagents.
• They have adjustable stores
• Driven - operated pumps.

17
Chemical Injection Pumps
18

• DEMULSIFIERS
• ALKAN DEMULSIFIER
• T _at_ 60o C (140o F)
• Combustible
• 1 gallon per 20,000 gallons (50 ppm) of oil
• 1 gallon per 10,000 gallons (100 ppm) of oil

19
Demulsification Experiment

• Water Concentration 20 vol..
• Time of mixing 20 min.
• 2000 RPM.
• Salt conc. 100000 ppm
• Demulsifiers conc. (10,25,50,100 ppm)
• Plot (volume precipitated vs. Time)

20
(No Transcript)
21
Demulsifier conc.
22
Horizontal Separator Sizing

• Sizing parameters

Height
Length
23
Horizontal Separator Sizing

• Retention time method.
• Drop settling method.
• Design consideration.

24
Horizontal Separator Sizing

• Basis
• Operating temperature 60 oC
• Operating pressure 1 atm
• Retention time 5 minutes
• Production rate 50,000 barrel/day

25
Horizontal vessel design equations

• Diameter calculation
• (p/4) D2 M Leff q tr
• Volume calculation
• V C (sh1 sh2) / µw ) (D/1440)
• Length calculation
• L (4/3) D Leff

26
Calculations results
27
PID Contents

• 1) All process equipment are identified by an
  equipment No.
• 2) All pipes are identified by a line No. (pipe
  size material of construction)

28

• 3) All control and block valves are identified
  by numbers. (type size)
• 4) Pumps are identified by a code No.
• 5) All control loops instrument are with an
  Identification No.

29
Types of Valves
CV
Electronic
Butterfly Valve
Pneumatic
Fails Open
Fails Shut
30
PID Objectives

• (I) Safe Plant Operation
• -To keep process variables within the safe
  operating limits.
• -To provide alarms and automatic shut-down
  system, to detect dangerous situations as they
  develop.
• -To provide interlocks and alarms, to prevent
  dangerous operating procedures.

31
PID Objectives

• (II) Production Rate
• -To achieve the design product output.
• (III) Product Quality
• -To maintain the product composition within the
  specified quality standards.
• (IIV) Cost
• -To operate at the lowest production cost.

32
(No Transcript)
33
Hazards and Operability Studies (HAZOP)

• Basic Principles
• Involves systematic study of the process.
• Vessel by vessel
• Line by line
• Guide words

34
Guide words

• No or Not (No part of the intention is achieved
  but nothing else happens).
• More (Quantitative increase)
• Less (Quantitative decrease).

35
Additional guide words

• Intention
• Deviation
• Causes
• Consequences
• Hazards

36
Objective of guide words

• Special words are used in a systematic fashion
  (HAZOP procedure).
• To investigate potential hazards and possible
  solutions.

37
(I) Intention- emulsion stream transfer from
knock out drum to indirect heater
38
HAZOP
39
HAZOP
40
(No Transcript)
41
(II) Intention- Outlet stream from indirect
heater to the horizontal separator
42
HAZOP
43
HAZOP
44
Indirect Heater

• Energy needed to heat the crude Q
• Q 15 Fo DT (0.5 r 0.2)
• Q 11,790,000 Btu/hr
• Vessel size
• O.D 96
• L 30

45
Indirect Heater PID
46
Environmental Impact

• Burning of fuel gas causes the emission of CO2,
  H2S..etc to the atmosphere

47
Combustion
48
Fuel Gas
49
Combustion
50
Indirect Heater Efficiency

• Addition of flue gas passes.
• Attending to leaks.
• Insulating Pipe work and exposed surfaces.

51
Experimental Design

• The apparatus consist of
• Mixing tank
• Mixer
• Pump
• Pipes
• Separation tank
• Weir
• Valves

52
Experimental Design
53
Weir Separator
54
Calculations

• The calculations include
• The dimensions of the separation tank.
• The height of the weir.
• The flow rates coming in and out of the
  separation tank.
• The location of the feed.
• Pump.

55
Dimensions

• Volume 27 liters
• Oil
• Water
• Demulsifier (Alkan)
• Emulsifier (Triton X100)

56
Dimensions
57
Flow Rates

• Flow Rate In Rate of Water Out Rate of Oil
  Out.
• Residence time (t)
• Volume (V)
• Volumetric flow rate (Q V / t)

58
Calculations

• Feed location (h)
• 20 x (Volume) / (Area)
• P P atm ?g h
• P 101.325 Kpa 0.08 Kpa 101.405 Kpa

59
Pump calibration
60
Pump calibration
61
Materials of construction

• Mechanical Properties.
• Corrosion resistance.
• Sulfur Stress Corrosion.
• Temperature Corrosion.
• Pitting.

62
Process Flow Diagram
63
Materials of construction

• KnockOut Drum.
• Carbon Steel.
• Indirect Heater.
• Stainless Steel 316.
• Three Phase Separator
• Carbon Steel.

64
Cost

• Manufacturing Companies.
• NATCO, ALFALAVAL, SOFRESID, etc.
• KnockOut Drum.
• 50,000-200,000
• Indirect Heater.
• 350,000 -750,000
• Three Phase Separator
• 100,000-300,000

65
T
K
A
N
H
Y
U
O
F
R
O
I
S
E
N
N
G
L
I
T