11Prepared by // Eng. Ahmed Mohamed Shoman

2

Content• Definitions of Frequently Used Parameters in Natural Gas

Industry.

• Introduction for natural gas.1. Natural Gas Terminology. 2. Natural Gas Formation.3. Natural Gas Composition.4. Natural Gas Properties.5. Natural Gas Phase Behavior..

• Natural Gas Conditioning.• Field Separation.• Gas Sweetening.• Gas Dehydration.

Sweetening /Dehydration Trouble Shooting (Amine & Glycol Unit).

– Gas is not Sweet– Amine solution not regenerated– Dirty, degraded amine – Excessive Corrosion – Foaming of amine solution – Inlet gas temperature too low – Wrong or off-spec – chemicals – Misuse or abuse of antifoam chemicals in amine units – Incoming gas is not adequately scrubbed and contains salt water – Tray down comers are plugged, causing amine to stack up in the trays .

3

Content

• NGL Recovery

– NGL and LPG recovery technology.– GTL production technologies.- Separation of NGL

• Examples for Gas Plants Ras Shukier Gas Plant . "GUPCo" Amreya Gas Plant. Port Said NGL Plant. The UGD Company. Syrian "Dier El-zour " D.Z Gas Plant. Ras Shukier NGL Plant "EBGDCO"

• Natural Gas Processing.

By Refrigerated lean oil Absorption. By J.T and LTS. By Turbo Expander.

4

Content• Fractionation Towers.– Types of Fractionation Tower.– Types of Trays.– Tray Towers Operation Problems.– Packing Types

• Sulfur Recovery Unit “SRU”: – Sulfur content in natural Gas & its Economic Value.– SRU “ Clause process”

• Natural Gas Compression

• o   Introduction

• o   Reciprocating Compressors• o   Centrifugal Compressors• o   Comparison between Compressors• o   Compressor Selection• o   Multistage Compression• o   Compressors Calculations • o   Compressor Performance Maps

55

Definitions

1- Associated Gases : Gas associated with liquids.

2- Non associated gases: Gas produced from gas wells without liquids.

3- Dry gas : Natural gas is considered 'dry' when it is almost pure methane, having most of the other commonly associated

hydrocarbons removed.

4- Wet gas : When other hydrocarbons are present, the natural gas is 'wet'.

5- Sour gas : Natural gas which contains H2S and CO2 (acid gases).

6- Sweet gas : natural gas which doesn’t contains H2S and CO2.

66

Definitions

7- Hydrated gas : Natural gas which contains H2O.

8- Dehydrated gas: Natural gas after removal of H2O.

9- LNG : Liquefied natural gas , mainly CH4

10- LPG : Liquefied petroleum gases , “Commercial Propane- Butane mixture”

11- Condensate : pentanes and heavier , C5+

12- GTL : Gas to liquids.

13- NGL : Natural gas liquids , ethane and heavier.

14- SRU : Sulfer Recovery Unit

77

Definitions15- Acid Gas : Feed stream to sulfur recovery plant consisting H2S, CO2, H2O, and usually less than 2 mol % hydrocarbons.

16-Claus Process:The process in which 1⁄3 of the H2S in the acid gas feed is burned to SO2 which is then reacted with the remaining H2S to produce sulfur. This is also referred to as the modified Claus process. ( H2S + 1⁄2 O2 → S + H2O )

17-Residence Time: the period of time in which a process stream will be contained within a certain volume or piece of equipment, seconds.

18-Tail Gas Cleanup Unit: a process unit designed to take tail gas from a Claus sulfur recovery plant and remove additional sulfur with the goal of meeting environmental sulfur emission standards.

88

Introduction:

Natural Gas is a vital component of the world's supply of energy. It is

one of the cleanest, safest, and most useful of all energy sources.

What is Natural Gas: Natural gas is a combustible mixture of hydrocarbon gases( from CH4

to C8H18”OCTANE) consisting essentially of METHANE ,other

hydrocarbons and non Hydrocarbon Gases in gaseous state ,which is

extracted from the subsurface of the earth in its natural state ,separately or

together with liquid hydrocarbons

99

The Formation of Natural Gas:

Natural gas is a fossil fuel like oil and coal.

Fossil fuels are, essentially, the remains of

plants ,animals and microorganisms that

lived millions and millions of years ago.

1010

Natural Gas Under the Earth:

Although there are several ways that methane,

and thus natural gas, may be formed, it is

usually found underneath the surface of the

earth. As natural gas has a low density, once

formed it will rise towards the surface of the

earth through loose , shale type rock and other

material.

With natural gas trapped under the earth in this

fashion, it can be recovered by drilling a hole

through the impermeable rock. Gas in these

reservoirs is typically under pressure, allowing it

to escape from the reservoir on its own.

1111

Typical Composition of Natural Gas :

LNGLNG

Pentane

Methane

NitrogenCO2,H2S, Hg

Water

Ethane

Propane

Butane

C5 +

NGL’sNGL’s

LPGLPG

Impurities

Octane

HexaneHeptane

1212

Typical Composition of Natural Gas :

1313

Oxygen: Max. ( 0.1% ) by mole.

Carbon dioxide: Max. ( 3 % ) by mole.

Hydrogen sulphide: Max. ( 4 ) PPM

Sulphur: Max. (50 ) mgm / SCM

Mercury: Max. (6 ) mgm / SCM

Oxygen: Max. ( 0.1% ) by mole.

Carbon dioxide: Max. ( 3 % ) by mole.

Hydrogen sulphide: Max. ( 4 ) PPM

Sulphur: Max. (50 ) mgm / SCM

Mercury: Max. (6 ) mgm / SCM

**

H.C. dew point: ( +5 ) Deg.CGross Heating Value : Min. 980

Max. 1180 BTU/SCF.Water dew point : MaxPPM ( 1 ) or below

Deg. C at a pressure of ( 70 ) kg /cm2 gauge ( zero ).

H.C. dew point: ( +5 ) Deg.CGross Heating Value : Min. 980

Max. 1180 BTU/SCFWater dew point : Max. ( 1 ) PPM or below

( zero ) Deg. C at a pressure of ( 70 ) kg /cm2 gauge.

********

****

14

Natural Gas Properties

15

Ideal Gas Law

Where :

P : Absolute pressure

V : Volume

T : Absolute temperature

R : Universal gas constant

n : Number of moles n = m / M

m : Mass of the gas

M : Molecular weight

PV =

nRT

PV = (m/M) RT

m = MPV/RTm/V = ρ = MP/RT ρ is density of gas

m = MPV/RT

The ideal gas law can be expressed as :

m/V = ρ = MP/RT ρ is density of gasm = MPV/RT

m/V = ρ = MP/RT ρ is density of gas

16

Behavior of Real Gases

Where :

Z is deviation or compressibility factor and can be expressed as

Z = [ actual volume of n moles of gas / (ideal volume of n moles of gas

at certain P & T) at same P & T ]

where Z is dimensionless.

PV = ZnRT

17

Properties of Gaseous Mixtures

Composition of natural gas may be expressed as either mole fraction, volume fraction or weight fraction.

Mole Fraction yi = ni/∑ni

where: yi : Mole fraction of component i ni : Number of moles of component i

∑ni : Total number of moles of all components in the mixtures

Volume fraction vi = vi/∑vi

Weight Fraction wi =Wi/∑Wi

18

Determination of Z Factor

From the next chart after determination of Pr and Tr we can determine Z factor

Pr

Tr

Z

Determination of Z Factor

Pr = P / PcPr = P / Pc

Where :

Pc= ∑Pci*YiTc= ∑Tci*Yi

Tr = T / Tc

19

The natural gas phase behavior is a plot of pressure vs temperature thatdetermines whether the natural gas stream at a given pressure and temperature consists of a single gas phase or two phases: gas and liquid.

The phase behavior for natural gas with a given composition is typically displayed on a phase diagram, an example of which is shown in Figure 1-1.

The left-hand side of the curve is the bubble point line and divides the single phase liquid region from the two-phase gas–liquid region.

The right-hand side of the curve is the dew point line and divides the two-phase gas–liquid region and the single-phase gas region.

Natural Gas Phase Behavior

20

21

Retrograde region

liqui

dGasx yz

At point X:

Xi=xy/zy

Yi=xz/zy

22

Definitions

1-Phase DiagramA record of the effects of temperature, pressure and composition on the kinds and numbers of phases that can exist in equilibrium with each other.

2-Bubble PointThe point at which the first small vapour bubble appears in a liquid system. The bubble point curve on a phase diagram represents 0% vapour.

3-Dew PointThe point at which the first infinitesimally small droplet of condensation forms in a gaseous system. The dew point curve on a phase diagram represents 0% liquid.

4-Phase EnvelopeThe area on a pressure-temperature phase diagram for a mixture enclosed by the bubble and dew point curves. This area represents the set of conditions for the

mixture were vapour and liquid phases co-exist in equilibrium .

5-Cricondenbar (Pmax) The maximum pressure at which vapour and liquid can co-exist in equilibrium.

23

Definitions6-Cricondentherm (Tmax) The maximum temperature at which vapour and liquid can co-exist in equilibrium.

7-Critical PressureThe vapour pressure at critical temp.

8-Critical TemperatureThe temp. above which all the mixture cannot be liquid

9-Quality LinesLines through the two-phase region showing a constant percentage of liquid and vapour.

10-RetrogradeThe name given to phase behaviour above the critical temperature and pressure

were vapour and liquid phases coexist and the amount of vaporisation or condensation changes with pressure and temperature in the opposite direction to normal behaviour. (e.g:condensation of liquids occur by lowering pressure or increasing temperature)

24

Definitions 11-Equation of State (e.g : ideal gas law)An equation which describes the relationship between pressure, temperature and molar volume of any homogenous fluid at equilibrium

12- Critical PointThe point on the phase diagram where The bubble point and dew point lines intersect , where the distinction between gas and liquid properties disappears.

The natural gas phase behavior is a function of the composition of thegas mixture and is strongly influenced by the concentration of the heavier hydrocarbons, especially C+ . The presence of heavier hydrocarbons will increase the phase envelope and failure to include them in a phase calculation will under predict the phase envelope.As shown by the next exmple:

25

26

2727

36.1 %36.1 %

36.2 %36.2 %

3.1 %3.1 %4.9 %4.9 %

4.6 %4.6 %

7.2 %7.2 %

7.9 %

0

500

1000

1500

2000

2500

N-America S-America Europe Africa Mid-East Sov-Countries

Asia/Austr.

( TSCF )

2828

Methane:Fertilizer /Methanol/Olefin / Fertilizer /Methanol/Olefin / GTL FeedstockGTL Feedstock

Ethane :Petrochemical Petrochemical Feedstock.Feedstock.

Propane:Petrochemical Feedstock Petrochemical Feedstock or Fuel.or Fuel.

I-Butane:Refinery Feedstock / Refinery Feedstock / Fuel.Fuel.

N-Butane:Gasoline Blending / Gasoline Blending / Fuel / Petrochemical Fuel / Petrochemical Feedstock.Feedstock.

Natural Gasoline (IC5+)Condensate

Refinery Feedstock or Refinery Feedstock or Petrochemical Petrochemical Feedstock.Feedstock.

NATURAL GAS

NATURAL GAS

2929

SeparationSeparation between the Oil &Gas between the Oil &Gas

Sweetening Sweetening remove the Acid Gasesremove the Acid Gases

Dehydration Dehydration remove the Water vapourremove the Water vapour

H.C Dew Point & Heating ValueH.C Dew Point & Heating Value

Extraction (Extraction (ProcessingProcessing)) Main TargetMain Target

-Extract main component into -Extract main component into separate products which areseparate products which are

MethaneMethane

EthaneEthane

Propone Propone

LPGLPG

Natural GasolineNatural Gasoline

ConditioningConditioning

Main TargetMain Target

3030

31

Training Videos

I- Natural Gas Processing Principles

30

33

Gas ConditioningGas Conditioning

• Field Separation.• Gas Sweetening.• Gas Dehydration.

3434

Export

HP Gas

LC LC

LC

Pump

CoolingDehydration/

Desalter

Water

Heating/Cooling

Water

HP Separator

Heating/Cooling

LP Gas

LP Separator

• Large Vessels are used to separate the gas, oil, water and sand using their different densities.

• Sufficient time has to be given to allow the water droplets to settle from the oil and vice versa.

• Multiple stages are used to liberate gas and remove water.

• The number of stages is assessed balancing cost, energy efficiency, effect on the reservoir and safety.

• The separation process may require heating to help destabilise oil-water emulsions.

• Chemicals are utilised to assist droplet coalescence, break foams and prevent corrosion.

• To prevent remixing and effective separation the separator is fitted with a range of devices.

3535

Separator InternalsSeparator Internals• Internals design is often key to

efficient separator operation.

– Inlet device to reduce liquid momentum (centrifugal/impingement)

– Distributor plate– Coalesce pack to

provide surface area for small droplets to coalesce to larger ones, enhancing liquid/liquid separation

– Vane packs or demisters to collect oil droplets from the gas

– Vortex breakers to prevent gas underflow

– Sand jets to remove sand from the separator

– Foam packs

3636

Cyclone Inlet Device

Foam Reducing Pack Assembly

Inlet Diffuser & Cascade TrayBaffle Plate Set

Separator InternalsSeparator Internals

Cyclone Inlet Device with

Perforated Baffle Plate

3737

Separators TypesSeparators Types

• Horizontal Separators– Large liquid handling

capacity– Sufficient time for settle out

of liquid droplets from the gas

• Vertical Separators (scrubbers)– High gas volumes– Small footprint area

• Separator features :– Primary separation section to

separate the bulk of the liquid from the gas

– Sufficient capacity to handle liquid surges

– Sufficient liquid residence time to allow small droplets to settle out

– Some inlet device to reduce turbulence and velocity in the main separation section

– A mist extractor to capture entrained droplets

– Back pressure and liquid level controls

– Relief and blowdown– Sand washing

38

Training Videos

II- Natural Gas Separators Principles

30

3939Day#2

4040

•Sweetening process is to remove acid gases from natural gases.

•This can be done either by adsorption or absorption processes.

•The most famous adsorption process is solid desiccant beds which can perform Sweetening and dehydration for natural gas at the same time with higher efficiency.

•The most famous absorption process is amine.

4141

AMINE PROCESS

4242

CHEMICAL ABSORPTIONCHEMICAL ABSORPTION

HO-C - C-

H

H

H

H

4343

4444

Typical

45

46

FIG. 21-5Physical Properties of Gas Treating Chemicals

“weak bases”

PropertyMono-

EthanolamineDi-

EthanolamineTri-

Ethanolamine

FormulaHOC2H4NH2)HOC2H4)2NH)HOC2H4)3N

Molecular Wt61.08105.14148.19

Boiling point @ 760 mm Hg, °C

170.5269360) decompose)

Density @ 20°C, kg/m3.

101810951124

47

Check solution concentration: – Too low : Check make up water addition.Check amine flow rate: – Too low : Open by pass valve.Check amine regeneration: – Increase firing rate.Check reflux rate and temperature: – Probably too low : Increase firing rate.Check stripping column pressure: – It may be too low Check for foaming : – Carry over into outlet separator and / or pressure fluctuations across

absorber.

•A brief review of the more frequent problems and corrective procedures follow :

1- Gas is Not “ Sweet “/Dehydrated

48

• Check reboiler temperature ,pressure and the reflux rate.

• Check for leaks in lean/rich amine heat exchanger.

• Check the re-claimer for primary amine. • Check for foaming in stripper : - pressure fluctuations.

2- Amine solution not regenerated

49

• Gas contains oxygen. • Storage or make up tank blanket gas valve is

not functioning: - Repair if any.• Make up water contains free oxygen: - Add oxygen scavenger or use distillated

water.• Sparge amine with sweet gas to strip oxygen.

3- Dirty, degraded amine

50

Amine concentration is too high: Add make up water .

Amine is highly degraded: Replace .

Make up water is high in dissolved solids : Treat make up water or use deionized water.

Insufficient amine regeneration:

Insufficient amine filtration : Increase filter rate or change filter elements more frequently.

Qxygen is entering system: Eliminate.

Velocities too high : reduce temperature to stripper.

4- Excessive Corrosion

51

• Foaming is a very unpredictable phenomenon. It can be caused by any or a combination of the following conditions:

Dirty amine (solids) – check filter elements. Degraded amine. Liquid hydrocarbon in gas or amine.

5- Foaming of amine solution

52

• It will be caused by lower inlet amine temperature.

• So the Inlet amine temperature must be at least 10-15 oF above the inlet gas temperature to eliminate H.C condensation .

6- Hydrocarbon condensation

53

• Well treating chemicals. • Surfactants. • Corrosion inhibitors.• Very fine particles. e.g. iron sulfide, in sour gas. • Inadequate cleaning of amine plant before

start-up.

7- Wrong or off-spec – chemicals

54

• Make up water contains iron, sulfides, chlorides, etc…

(Use deionized or de-mineralized water)

9- Incoming gas is not adequately scrubbed and contains salt water

55

• (This is really not a foaming problem but behaves so; usually with older plants).

• Note : Always add antifoaming downstream of the

carbon filter. The following antifoaming are recommended Dilute with 50% isopropyl alcohol use in

concentrations of 5 to 50 PPMW .

10- Tray down comers are plugged, causing amine to stack up in the trays

56

Training Videos

II- Gas Sweetening “Amine Uint”

18

AMINE UNIT CASE STUDYAMINE UNIT CASE STUDY

57

Page 7

Gupco U104 amine unit

COS “Carbonyl sulfide” it is a colorless flammable gas with an unpleasant odor. It is a linear molecule consisting of a carbonyl group double bonded to a sulfur atom it decomposes to H2S & Co2 in presence of humidity and bases

5858

•Dehydration process is to remove water vapor from natural gases.•This can be done either by adsorption or absorption processes.• )gas 2 solid) )gas 2 liquid)

• The most famous adsorption process is solid desiccant beds which can perform Sweetening & Dehydration for natural gas at the same time with higher efficiency according to its material affinity and pour size .

• The most famous absorption process is Glycol unit.

Water in NG : Most free associated water removed by simple extraction method at

or near wellhead Water vapor in NG solution need more complex treatment Process of dehydration of NG – absorption or adsorption Pipeline specs: 7.0 lb H2O/MMSCF { max. =1 ppmv}

Day#3

59

Water Removal

Absorption “Glycol Dehydration”:

Glycol solution (high affinity to water) – diethylene glycol (DEG) or triethylene Glycol (TEG)

TEG/DEG contact wet gas stream (called contactor) absorb water glycol soln. sink to bottom removed

Glycol recovery – vaporize glycol using special boiler New tech: addition of flash tank separator condensers

before boiler to condense methane (90 – 99% recovery)

60

Solid-Desiccant Dehydration : “Adsorption”

Adsorption process consists of 2 or more adsorption tower filled with solid desiccant.

At least 1 working, 1 regenerating Desiccants: activated alumina or granular silica gel Wet NG pass through towers from top to bottom H2O

retains on particle surface dry NG exits saturated desiccant heated with heater to vaporize water

Best suite for large volumes gas under very high P

6161

6262

HYDRATES IN NATURAL GAS SYSTEMS

• A hydrate is a physical combination of water and other small molecules to produce a solid which has an “ice-like” appearance but possesses a different structure than ice. , it cause flow interrupting.

• There are three recognized crystalline structures I,II,H

• Their formation in gas and/or NGL systems can plug pipelines, equipment, and instruments, restricting or for such hydrates. In both, water molecules build the lattice and hydrocarbons, nitrogen, CO2 and H2S occupy the cavities.

63

• HYDRATES IN NATURAL GAS SYSTEMS

• Smaller molecules (CH4, C2H6, CO2, H2S) stabilize a body-centered cubic called Structure I.

• Larger molecules (C3H8, i-C4H10, n - C4H10) form a diamond-lattice called Structure II.

• Normal paraffin molecules larger than n-C4H10 do not form Structure I and II hydrates as they are too large to stabilize the lattice.

However, some iso paraffins and cyclo –alkanes larger than pentane are known to form Structure H hydrates.

6464

6565

Hydrocarbons )C1,C2,C3,iC4+nC4) and / or H2S, N2, CO2

+Metastable H20

@)P, T)

------------------------------------------=

HYDRATES

Metastable water is liquid water which, at equilibrium, will exist as a hydrate

6666

The conditions which affect hydrate formation are:

1- Primary Considerations

• Gas or liquid must be at or below its water dew point or saturation condition. To allow water droplet condensation• Temperature.

• Pressure.

•Composition.

2- Secondary Considerations

• Mixing.

• Kinetics

• Physical site for crystal formation such as a pipe elbow, orifice, thermowell, or line scale.

• Salinity.

6767Th

P

hydrate formation line , function of composition

FIG. 20-4 Water Content of Hydrocarbon Gas

6868

Hydrate Inhibition

•The formation of hydrates can be prevented by dehydrating the gas or liquid to eliminate the formation of a condensed water )liquid or solid) phase.• In some cases, however, dehydration may not be practical or economically feasible.• In these cases, chemical inhibition can be an effective method of preventing hydrate formation.

• Chemical inhibition utilizes injection of thermodynamic inhibitors or low dosage hydrate inhibitors (LDHIs).

•Thermodynamic inhibitors are the traditional inhibitors )i.e., one of the glycols or methanol), which lower the temperature of hydrate diminish formation “Th”

•LDHIs are either kinetic hydrate inhibitors (KHIs) or anti - agglomerants (AAs).• They do not lower the temperature of hydrate formation, but do its effect.

70

Natural Gas Dehydration

by: Liquid & Solid Desiccants

71

72

73

74

75

76

77

78

79

                                                                                                                                                        

Glycol Dehydration UnitGlycol Dehydration UnitDay #3

80

81

Ethylene GlycolDi-ethylene Glycol

Tri-ethylene Glycol

Tetraethylene Glycol

FormulaC2H6O2C4H10O3C6H14O4C6H18O5

Molecular weight62.1106.1150.2194.2

Boiling point at 760 mm Hg, °F387.1472.6545.9597.2

Boiling point at 760 mm Hg, °C197.3244.8285.5314

Vapor pressure at 77°F (25°C) mm Hg0.120.0020.00040.00005

Vapor pressure at 140°F (60°C) mm Hg1.50.080.025< 0.01

Density (g/cc) at 77°F (25°C)1.1101.1131.1191.120

Density (g/cc) at 140°F (60°C)1.0851.0881.0921.092

Density (Kg/m3 ) at 77°F (25°C)1110111311191120

Freezing point, °C-13-8-7-5.5

Pour point, °C--54-58-41

Viscosity in centipoise at 77°F (25°C)16.528.237.344.6

Viscosity in centipoise at 140°F (60°C)4.686.998.7710.2

Surface tension at 77°F (25°C), dynes/cm47444545

Specific heat at 77°F (25°C), kJ/(kg.K)2.432.302.222.18

Flash point, °C (PMCC)116124177204

Fire point, °C (C.O.C.)118143166191

Initial decomposition temperature °C 165164207238

GLYCOLS PHYSICAL PROPERTIES

HO—)CH2)2—OH

82

Training Videos

III- Gas Dehydration “Glycol Unit”

15min

10 min.

8383

8484

GLYCOL DEHYDRATION UNITGLYCOL DEHYDRATION UNIT

85

86

87

DEA : 2-6 M3/100 LIT

88

89

90

91

92

93

99’C

195 ’C

94

95

96

97

Training Videos

IV- Gas Dehydration “Principles of Glycol Unit”

15min

98

                                                                                                                                                        

Solid Adsorpant Dehydration Solid Adsorpant Dehydration UnitUnit

9999

100100

101101

Molecular Sieves Adsorber / Internal Molecular Sieves Adsorber / Internal ArrangementArrangement

102102

GAS DEHYDRATION / Molecular sievesGAS DEHYDRATION / Molecular sieves

103103

GAS DEHYDRATION / Molecular sievesGAS DEHYDRATION / Molecular sieves

104104

GAS DEHYDRATION / Molecular sievesGAS DEHYDRATION / Molecular sieves

105105

GAS DEHYDRATION / GAS DEHYDRATION / Molecular sievesMolecular sieves

106106

GAS DEHYDRATION / Molecular sievesGAS DEHYDRATION / Molecular sieves

107107

GAS DEHYDRATION / Molecular sievesGAS DEHYDRATION / Molecular sieves

108108

GAS DEHYDRATION / Molecular sievesGAS DEHYDRATION / Molecular sieves

109

4-E34-E3

AmineAmineUnitUnit

4-V

154-

V15

4-V

434-

V43

4-H1D4-H1D

4-V

143

4-V

143

P. Eng. / A.ZP. Eng. / A.Z

GUPCO U-104 G/PGUPCO U-104 G/PDryers SchemeDryers Scheme

PH-IPH-I

PH-IIPH-II

Pg.9 Of 10Pg.9 Of 10

4-D

1A4-

D1A

4-D

1B4-

D1B

4-D

1C4-

D1C

4-F174-F17

4-F1174-F117

4-C101A/B4-C101A/B

4-C1A/B4-C1A/B

BDV-4001BDV-4001

4-C3A/B4-C3A/B

4-C103A/B4-C103A/B

ESD-1908ESD-1908

ESD-1907ESD-1907

Tie-inTie-in

Tie-inTie-in

4-D

101C

4-D

101C

4-D

101B

4-D

101B

4-D

101A

4-D

101A

4-C5A/B4-C5A/B

FV-4001FV-4001

FV-4002FV-4002F

V-4

003

FV

-400

3

FV

-400

6F

V-4

006

FV-4007FV-4007

2FV

-401

12F

V-4

011

FV

-400

5F

V-4

005

FV-4004FV-4004

2FV

-401

22F

V-4

012

2FV-40132FV-4013

2FV-40142FV-4014

2FV-40152FV-4015

2FV

-401

62F

V-4

016

2FV

-401

72F

V-4

017

2FV

-401

82F

V-4

018

2FV-40192FV-4019

2FV

-402

02F

V-4

020

4-F2174-F217

MDVMDV40014001

RDVRDV40074007

MDVMDV40034003

RDVRDV40094009

MDVMDV40054005

RDVRDV40114011

MDVMDV40024002

RDVRDV40084008

MDVMDV40044004

RDVRDV40104010

MDVMDV40064006

RDVRDV40124012

2MDV2MDV40014001

2RDV2RDV40074007

2MDV2MDV40034003

2RDV2RDV40094009

2MDV2MDV40054005

2RDV2RDV40114011

2MDV2MDV40024002

2RDV2RDV40084008

2MDV2MDV40044004

2RDV2RDV40104010

2MDV2MDV40064006

2RDV2RDV40124012

110

P. Eng. / A.ZP. Eng. / A.Z

Molecular Sieve ChargeMolecular Sieve Charge( 80,200 lb )( 80,200 lb )

Upper ScreenUpper Screen(( 20 Piece ) 20 Piece )

1” Ceramic Ball ( 52 CF )1” Ceramic Ball ( 52 CF )

1/8” Ceramic Ball ( 26 CF )1/8” Ceramic Ball ( 26 CF )

1/4” Ceramic Ball ( 26 CF )1/4” Ceramic Ball ( 26 CF )

4-D1A/B/C Dimensions4-D1A/B/C Dimensions

3”3”

3”3”

6”6”

Pg.10 Of 10Pg.10 Of 10

Lower ScreenLower Screen

Dimensions:Dimensions: 144” I.D144” I.D 20’ S/S20’ S/S

111

Table 1Table 1

Process StepProcess Step112233445566

44--D1AD1ADDDDDDHHCCDD

44--D1BD1BDDHHCCDDDDDD

44--D1CD1CCCDDDDDDDDHH

44--D101AD101ADDDDDDDDHHCC

44--D101BD101BDDDDHHCCDDDD

44--D101CD101CHHCCDDDDDDDDFV-4003, 2FV-4015, 2FV4018, FV-4003, 2FV-4015, 2FV4018,

2FV-40202FV-4020OpenOpenCloseCloseOpenOpenCloseCloseOpenOpenCloseClose

FV-4004, 2FV-4016, 2FV4017, FV-4004, 2FV-4016, 2FV4017, 2FV-40192FV-4019CloseCloseOpenOpenCloseCloseOpenOpenCloseCloseOpenOpen

Molecular Sieve Operation ChartMolecular Sieve Operation Chart

113113

DAY# 4

114

1. By lean oil absorption

2. By Refrigeration & LTS.

3. By Cryogenic Process

115115

116116

Sales . GasSales . GasSales . GasSales . Gas

FeedFeed

WaterWater

InletSeparator

Cond.Cond.

CompressorCompressor

Wet . GasWet . Gas

Dry . GasDry . Gas

Dehydration

ExchangerExchanger

LTSLTS

F.GF.G

To. StabilizerTo. Stabilizer

StabilzerStabilzer

FlareFlare

CoolerCooler

117117

Cryogenics : Is the study of the production of very low temperature materials )below −43°C) and the behavior of materials at those temperatures.

118

Process Units Deethanizer – separates ethane from NGL stream Depropanizer – separates propane Debutanizer – boils off butanes leaving pentanes and

heavier HC in NGL stream Butane splitter (Desiobutanizer) – separates iso and n

butanes

ComponentBP oF at 1 atm

Ethane-127 (-88 oC)

Propane-44 (-42) oC

Iso-butane11 (-11 oC)

n-butane31 (-0.5 oC)

Pentane 97 (36oC)

119119

Turbo Expanders• The use of turbo expanders in gas processing plants began in the early sixties.

• By 1970, most new gas processing plants for ethane or propane recovery were being designed to incorporate the particular advantages characteristic of an expander Producing usable work.

• The trend in the gas processing industry continues toward increased use of the turbo expander.

• Selection of a turbo expander process cycle is indicated when one or more of the following conditions exist:

“Free” pressure drop in the gas stream.

Lean gas.

High ethane recovery requirements )i.e., over 30% ethane recovery).

Compact plant layout requirement.

High utility costs.

Flexibility of operation )i.e:easily adapted to wide variation in pressure and products).

120120

Turbo expanders

121121

• This figure represents the pressure- temperature diagram for this expander process.

• The solid curve represents the plant inlet gas & the dashed one represent expander inlet gas )less in heavy H.C)

• At a fixed pressure and, if the temperature of the gas is to the right of this dew point line, the gas is 100 percent vapor.

• If the gas is cooled, liquid starts to condense when the temperature reaches the dew point line.

• As cooling continues, more liquid is condensed until the bubble point line is reached — the solid line on the left. At this point, all of the gas is liquid. Additional cooling results in colder liquid

Turbo expanders

122122

• A turbo expander recovers useful work from the expansion of a gas stream. • The process operates Isentropically in the ideal case and produces something less than the theoretical work in the real case. • In the process of producing work, the expander lowers the bulk stream temperature which can result in partial liquefaction of the bulk stream.

Turbo expanders

123123

De-MethaniserDe-PropaniserDe-MethaniserDe-Propaniser

To De-EthaniserDe-Butans

To De-EthaniserDe-Butans

To Sales GasCompressorTo Sales GasCompressor

Q-1Q-1

77

11

DehydrationPkg

DehydrationPkg

Feed Gas

Feed Gas

33 44

L t s L t s

Recomp

Recomp

Expander

Expander

Jt ValveJt Valve

124

Mixed Refrigerant Processes”"

Mixed Refrigerant Processes are used through LNG/NGL plants to

avail sub-cooling for natural gas where a single mixed refrigerant is used

)composed of nitrogen, methane,ethane, propane, butane and pentane).

The refrigerant is designed so that the refrigerant boiling curve nearly

matches the cooling curve of the gas being liquefied. The closeness of

the match of these two curves is a direct measure of the efficiency of the

process.

125

The low pressure refrigerant is compressed and condensed

against air or water in a closed system. The refrigerant is not totally

condensed before being sent to the cold box. The high pressure

vapor and liquid refrigerant streams are combined and condensed

in the main exchanger.

The condensed stream is flashed across a J-T valve and this low

pressure refrigerant provides the refrigeration for both the feed gas

and the high pressure refrigerant.

see fig 16-31 GPSA sec.16 in which,

“Cold box exchangers”

The cold box is a series of aluminum plate fin exchangers which provide

very close temperature approaches between the respective process streams.

126

Training Videos

IIV- Cryogenic Principles

15min

127

Examples for LPG,NGL and Examples for LPG,NGL and LNG Gas PlantsLNG Gas Plants

128128

Sales GasSales Gas

LPGLPG

COND.COND.

LPGLPG

COND.COND.

4-W1054-W105

4-W4A4-W4A

4-W4B4-W4B

4-W4C4-W4C

4-W104A4-W104A

4-W104B4-W104B

4-T

10

24

-T1

02

4-T

10

14

-T1

01

4-T

24

-T2

4-T

14

-T1

4-C3A4-C3A

4-C3B4-C3B

Chilling Area PH-IChilling Area PH-I

Chilling Area PH-IIChilling Area PH-II

Drying Area PH-IDrying Area PH-I

Drying Area PH-IIDrying Area PH-II4-C103A4-C103A

4-C103B4-C103B

4-D

1A

4-D

1A

4-D

1B

4-D

1B

4-D

1C

4-D

1C

4-D

10

1A

4-D

10

1A

4-D

10

1B

4-D

10

1B

4-D

10

1C

4-D

10

1C

4-W101B4-W101B

4-W101A4-W101A

4-W1A4-W1A

4-W1B4-W1B

Compression Area

-Compress gas press from 6-47 kg/cm .

- pre-separation for heavy H.C

Fractionation Area

- Produce LPG & Condensate

Expansion & Chilling Area

Separate Heavy H.C by cooling down to -60 ‘c

Boosting & Sales Gas Comp.

Send sales gas to GASCO net ) 64-100) kg/cm2

Utilities- Inst. Air System- Heating Oil System- Refrigeration Package- Cooling Water System- Power House- Fuel Gas System- Multi-Nozzle Flare System- Nitrogen Unit- Loading Area-Storage Area-LPG Berth # 4

129129

M

1.85 Bar120.8 C

M

30 –E -02

M

10-E-04

70 Bar30 C

1100 MMSCFD Inlet

SeparatorFilter

Dehydration Package

Mercury Removal

66 Bar40 C

28.3 Bar-50.9 C

28.5 Bar-69.5 C

-33 C

-58 C

Plat Fin

Separator

64.7 Bar-24 C

64.7 Bar-35 C

28.2 Bar-36 C

Plat Fin

25.6 Bar-43 C

CompressorTurbo

Expander

26.6 Bar-68 C

31 Bar50 C

-74.4 C

-69.5 C

Abs

orbe

r

26.6 Bar-74.5 C

26.3 Bar-76 C 25.6 Bar

-43 C

27.3 Bar-31.7 C

Demethanizer Condenser

27.3 Bar-74.4 C

-33 C

-36 C

20 Bar78.2 C

Dem

etha

nizi

er

20 Bar-78.2 C

Dep

ropa

nize

r

30-E-01

LPG Rundown

Cools 13.5 Bar50 C

LPG Local Market

1215 T/D

Deb

utan

izer

10.2 Bar62 C

10.2 Bar50 C

DNG Rundoum CoolsCondensate ( Local Market )

( 348 T/D )

Depropanizer Condenser

18 Bar50.7 C

C3 Expert

( 925 T/D )

N.G ( 1043 MMSCFD )

Sales Gas ( MMSCFD )

1043

Propane T/D925

LPG T/D1215

Condensate T/D348

Packed TowerBubble cap( 30 Tray )

Packed Tower

130

Dust Filter F-451

Dehydration Dust FilterF- 416/417

Dehydration Gas ScrubberV-410

Mercury Removal Bed V-450

Dehydration inlet Filter \ Coalescer

F-412Dehydration Adsorbers

V-413/414/415

C-121/122

Warm Gas/Gas Exchanger E-221

Deethanizer Side ReboilerE-224

Deethanizer V-521

Cold Separator V-421

Cold Gas Reflux ExchangerE-222

P-621/622/623

Deethanizer Bottom ReboilerE-225

Feed P-695/696

Depropanizer ReboilerE-241

Depropanizer Reflux CondenserA-341

Depropanizer Reflux DrumV-441

DepropanizerT-541

Propane To Storage

Butane to Storage

Feed U-104

Exp/Comp Discharge CoolerA-321

Deethanizer Reflux Acc.V-422

JT

PCV-410

Residue Gas To Pipeline

Regeneration Gas ScrubberV-418

Regeneration Gas HeaterE-211

Regeneration Gas CoolerA-311

Booster P-693/694

Depropanizer Reflux PumpsP-641/642

Regeneration Gas CompressorsC-111/112

132

15min

EXAMPLES FOR NGL GAS PLANTS

DOVE ENERGY-YEMEN PLANT

133133

NGL ExtractionNGL ExtractionTypical Product

Recoveries ( % ):Plant Type ->Product

Turbo-Expander

Joule Thompson

Lean OilRefrigeration

EthaneC2

60 – 96%45 – 60%25 – 45%1 – 5%

PropaneC3

90 – 98%85 – 95%80 – 95%20 – 40%

Iso-ButaneIC4

96 – 100%96 – 100%93 – 99%40 – 60%

N.ButaneNC4

97 – 100%97 – 100%94 – 99%40 – 60%

•NGL Recovery

134

Distillation or Fractionation Towers

and Tray Troubleshooting

135

Fractionation Towers• There are two main types of Fractionation Towers according to its

inside configuration :

• 1- Trays Towers .• 2- Packed Towers.

• Here below we will concentrate on Trays one as for its widely usage all over the world .

136

TRAY TYPS :Flow Regime

Trays Towers

137

TRAY TYPS :Perforation Regime

138

TRAY TYPS :Perforation Regime

139

140

141

142

Tray Towers Problem

143

1

Tray Towers Problem

144

2

Tray Towers Problem

145

3

Tray Towers Problem

146

4

Tray Towers Problem

147

Packing Types

148

149

BOOSTER STATION UTILITIES

Pig receiver

U-102 SLUG CATCHER

FM-Ashrafi 20’’FM-Hilal 20’’

8 ’’ 8’’

4’’

Fuel To Unit

GAS COMP. 2-C1A

GAS COMP. 2-C1B

GAS COMP. 2-C1C

GAS COMP. 2-C1D

Glycol Unit.

New Glycol

Unit

PCV-308 ESDV FT

FT

TO U-104

To Flare

12 ) ’’suco pipe line(

PI 19-26 Kg/cm2.gTI 50 C

PI 4.7 Kg/cm2.gTI 34 C

FT

PV-321

20’’

16’’

Closed

Process Div

check valves internals were already removed

152

BOOSTER STATION UTILITIES

* Utilities :

-Gas compressor-Heat Exchanger- Inst. Air System- Refrigeration Package- Cooling Water System- Power House- Fuel Gas System- Flare System- Nitrogen Unit- Storage Area

Natural GasNatural Gas CompressionCompression

Purposes of gas compression

Theory of gas compression

Main types of compressors

Centrifugal Compressor

Reciprocating Compressor

Purposes of Gas

Compression

For extra processing (liquefaction, dehydration & sweetening).

For transportation facilities.

Theory of Gas

Compression

PV = ZnRT = Z (m/M)RT

P1V1/T1 = P2V2/T2

1- Dynamic type (Centrifugal) P1

T1

V1

P2 T2 V2

Main Types of Compressors

Construction:

1- Rotor

−

+ + + ++

− −−

−

2- Stator

Anti-surge Control

2-Reciprocating Compressor:

Stroke

Piston

Compression chamber

Each cylinder consists of :

Piston

Chemise

Inlet valve

Outlet valve

Comparison of reciprocating & centrifugal compressors

162

15min

HEAT EXCHANGERS

15min

presentationvedio

163

Air intake filter

Air Blower

Fuel Gas

Combustion chamber Plate H.E

Potable water CW in

CW out

CW out

CW in

Exhausts Comp.

After cooler

Co2&H2O Absorber

OD

OD

OD

Cond. Water tape

N2 Reservoir Design 90 psig

80fo

To plant utilities

Cooling pumps

unit PFD2 N

air

Fuel gas

Exhaust N2

Cooling water

N2 UNIT

2-V21

2-V6

U-102

0

LV-716

LV-710

PIC-307 PIC -316A

PIC -316B

Hilal 4” FUEL GAS

168

CCourse Final quiz• 1// What is Natural Gas , definition , composition ,formation and uses? • 2// What the sections and devices of horizontal separators ? • 3// What does this Appreciations' mean?

– LNG - SRU– NGL - Acid Gas and tail gas– P&ID– PFD– LTS– Dew Point Depression .

• 4// What is the difference between the:• Absorption and Adsorption Process ? Give examples! • Hazard and Risk• 5// what is the recommended temp. difference between Gas & Liquid desiccant

interring to a contactor tower ? • 6// What are the Filter Types used at the TEG and DEA units ? (and purpose of every

type) • 7// draw a schematic drawing for a TEG typical Dehydration Unit ? • 8// What are the main four types of gas cryogenic process ?• 9// what are the Towers ‘ performance constraints & main cause of every constraints ?• 10// what are the rout parameters affect LPG Specifications at the Fractionation Area

?

------------------------------------------------------------------------------

169

11// why the TEG is widely used at Glycol Dehydration?

12// what the recommended temp./pressure for TEG still reboiler ?

13// What are the booster station utilities ?

14// what is the main types of compressors ? Advantages and disadvantages?

15// what are the main types of heat exchangers ? Give exapmles of H. Exchangers at your plant ?

16// what are the two types of air coolers ?

17// what is the solid disicants used at your plants?------------------------------------------------------------------------------

170

11// what are the main reactions take place at SRU?

12//what meant by sulfer recovery ? Feeds,products,recovery, components….

13// what are the operating parameters of SRU?

14// what are the precautions before the SRU start up?15//what is the source of SRU acid gas ?

16// why we treatment the tail gas?TGT?

17//what is the purpose of sulferpit degassing system? how does it work?

18// what is the blanket gas system, give example?

19//The 1/5 of h2s will be nurned out in the thermal claus reactor?

20//what are the waste heat recovery unit?

21//steam boiler in SRU? tell how & why !

------------------------------------------------------------------------------

THANKS ,,,THANKS ,,,

171

Eng. Ahmed Shoman Natural Gas Processing Engineer GUPCO "Gulf of Suez Petroleum Co."Mobile: +2-0122-743-2850 , +2-0100-800-4930e-mail: shomanAM@gupco.net / shomanNMC@yahoo.com