157883-000-cg-vt-0001

157883-000-CG-VT-0001

E&C Cryogenics Standard Plants Nitrogen Generation Unit (APSA L1) Training documentation

Peru LNG

E&C Cryogenics Standard Plants

- 4, rue des fusillés 94781 Vitry Sur Seine France Tel: + 33 (1) 45 73 66 66 - Fax : + 33 (1) 46 80 44 40

Author : ALSPE/CoH Revision: 0- 02-2009

Taining - PERU LNG Nitrogen Generation Unit

Generic part st

1 Day Welcoming introduction Process introduction Summary and training program philosophy Nitrogen Generation Unit systemic presentation PFD & PID Compression module Purification module sd

2 Day Heat Exchange module Distillation module Cold Production module Mass balance Safety : CnHm risks, safely operation

Operation training 3rd Day Process control – overview Start-up and shutdowns Deriming / Drying & exceptional regeneration Main control loops Alarms and trips Operating manual R01/R02 timing Supervision in steady conditions Trouble shooting quiz Operators questions and answers Training evaluation by participants Conclusions

CGG 09_018 dt 10th of april 2009

PRESENTATION

PERU LNG 2009

1

1. Generalities „

1.1. Nitrogen On-Site Supply System N2 purity 100%

APSA Small Cryo. Cryo.

Bulk Supply

APSA L APSA LE Large Cryo. Cryo. High Purity LIN

99.9%

SPI

AMSA

Small Membranes

Large Membranes

95% 10 100

1000

10000

N2 Production (Nm3/h)

PERU LNG 2009

2

1. Generalities „

1.2. APSA L /LE : Process and Markets

APSAAPSA-L

« Classic » 7-10 barA N2

Chemicals Refineries Glass

APSAAPSA-LC

Claude Cycle 2-3 barA N2

Glass

APSAAPSA-LE

Booster Re-cycle Ultra High Purity

Electronics

PERU LNG 2009

3

1. Generalities „

1.3. Air Separation Unit (ASU) Inlet & Outlet

SOURCE : Atmospheric Air

Air Separation Unit

PRODUCTS: O2, N2, Ar (gas or liquid)

WASTE NITROGEN

PERU LNG 2009

4

1. Generalities „

1.4. Raw material composition ELEMENTS

SYMBOL

OXYGEN NITROGEN ARGON HELIUM NEON KRYPTON XENON HYDROGEN STEAM CARBON DIOXIDE

O2 N2 Ar He Ne Kr Xe H2 H 2O CO2 CH4 C 2+

HYDROCARBONS

{

COMPOSITION IN VOLUME 20,9 78,1 0,93 5,24 18,18 1,139 0,086 0,5

% % % ppm ppm ppm ppm ppm

Principal

Rare gas

variable 300 à 700 ppm 3 à 5 ppm < 0.5 ppm

Impurities

PERU LNG 2009

5

1. Generalities „

1.5. Cryogenic production stages ?

COLD PRODUCTION HEAT EXCHANGE

PURIFICATION

COMPRESSION

DISTILLATION

PERU LNG 2009

6

1. Generalities „

1.6. Cryogenic production modular approach GASEOUS PRODUCTS

COLD PRODUCTION

Residual Gas HEAT EXCHANGE

Air PURIFICATION

COMPRESSION

DISTILLATION LIQUID PRODUCTS

PERU LNG 2009

7

1. Generalities „

1.7. Plant’s Modules Overview DISTILLATION

PURIFICATION

COMPRESSION

HEAT EXCHANGE

COLD PRODUCTION

PERU LNG 2009

8

1. Generalities „

1.8. APSA L : Global Scheme

Residual Gas

AIR

APSA L LIN GAN

• Nitrogen recovery ≈ 40%

PERU LNG 2009

9

1. Generalities „

1.9. APSA L : Process Cycle Gaseous N2 to customer

Residual Enriched Gas (>35% O2)

R01

Liquid N2 to backup

R02 D01

Air inlet

K01

C01

Compression Purification Power

Cooling Water

Cold Production

Heat Exchange

Distillation

Civil Works PERU LNG 2009

10

AIR PURIFICATION

PERU LNG - 2009

1

Air Purification

OBJECTIVES OBJECTIVES

TO TO REMOVE REMOVE THE THE VARIOUS VARIOUS AIR AIR CONTAMINANTS CONTAMINANTS IN IN ORDER ORDER TO TO PREVENT PREVENT TROUBLES TROUBLES IN IN APSA APSA UNITS: UNITS:

TEMPERATURE ~ -180°C

WATER WATER(air (airmoisture) moisture) Carbon CarbonDioxide DioxideCO2 CO2 Hydrocarbons HydrocarbonsCnHm CnHm Nitrous Nitrousoxide oxide(N2O) (N2O)

PERU LNG - 2009

2

Air Purification

WATER CO2 CnHm N2O

Purification Purification requirements requirements

-- unit unit corrosion corrosion -- plugging plugging (pipes, (pipes, exchangers, exchangers, column) column) by by solidification solidification due due to to cryogenic cryogenic temperature temperature (0°C (0°C // ice) ice)

-- plugging plugging (pipes, (pipes, exchangers, exchangers, column) column) by by solidification solidification due due to to cryogenic cryogenic temperature temperature (-130°C (-130°C // solid solid CO2) CO2)

- explosion explosion risk risk in in the the vaporizers vaporizers with with oxygen oxygen enriched enriched atmosphere atmosphere (Rich (Rich Liquid, Liquid, Oxygen) Oxygen)

- explosion explosion risk risk with with CnHm CnHm

PERU LNG - 2009

3

Air Purification Air Air Composition Composition // Air Air Contaminants Contaminants Air Composition

Inlet Comp. Normal

N2 O2 Ar

Nitrogen Oxygen Argon

78.11 % 20.96 % 0.93 %

H2 O CO2 CnHm

Water Carbon Dioxide Hydrocarbons

saturation 350 à 450 ppm Σ < 0.1 ppm

Ne He CH4 Kr H2 Xe

Neon Helium Methane Krypton Hydrogen Xenon

18 ppm 5.2 ppm 1 à 6 ppm 1.139 ppm 0.5 ppm 0.086 ppm

Inlet Comp. Peak

Purif. Outlet Max allowab

600 ppm 0.5 ppm

0.1 ppm

15 ppm

8 ppm

+ other natural or industrial impurities : hydrocarbons,CO, H2S, NO2 ..... PERU LNG - 2009

4

Air Purification

Process Process presentation presentation

Contaminant-free Air OBJECTIVES: OBJECTIVES: •• ELIMINATION ELIMINATION OF OF WATER WATER IN IN VAPOUR VAPOUR FORM FORM •• ELIMINATION ELIMINATION OF OF CARBON CARBON DIOXIDE DIOXIDE CO2 CO2 MOLECULAR SIEVE: CO2, CnHm

•• ELIMINATION ELIMINATION OF OF HYDROCARBONS HYDROCARBONS EXCEPT EXCEPT

METHANE METHANE CH4 CH4 and and some some other other CnHm CnHm

ALUMINA: WATER

Air Airpasses passesthrough throughupward upwardaavessel vessel equipped with two specific materials: equipped with two specific materials: - -ALUMINA: ALUMINA:to totrap trapwater watermolecules molecules Air with contaminants: H2O, CO2, CnHm

- -MOLECULAR MOLECULARSIEVE: SIEVE:to totrap trapCO2 CO2and and Hydrocarbon molecules Hydrocarbon molecules

PERU LNG - 2009

5

Air Purification

Adsorption Adsorption Process Process

ATTRACTION Molecules

Pores DIFFUSION/ FIXATION

Adsorbent

ALUMINA ALUMINA and and MOLECULAR MOLECULAR SIEVE SIEVE are are solid solid materials materials in in the the form form of of porous porous particles particles of of 22 to to 55 mm mm diameter: diameter: they they are are called called ADSORBENTS. ADSORBENTS.

The The ADSORPTION ADSORPTION process process occurs occurs in in 22 steps: steps: -- first, first, an an attraction attraction of of the the molecules molecules to to the the adsorbent adsorbent -- then, then, aa diffusion diffusion of of the the molecules molecules into into the the pores pores where where they they are are fixed fixed (or (or trapped). trapped).

PERU LNG - 2009

6

Air Purification

Adsorption Adsorption Process Process

Reversible Process : Adsorption & Desorption Adsorption Adsorption increases increases (the (the amount amount of of adsorbed adsorbed molecules molecules increases) increases) when: when: the the pressure pressure increases increases the the temperature temperature decreases decreases

Gaseous phase

Adsorbed phase

Solid

ADSORPTION ADSORPTION IS IS A A REVERSIBLE REVERSIBLE PROCESS: PROCESS: ifif the the pressure pressure decreases decreases or or ifif the the temperature temperature increases, increases, the the adsorbed adsorbed molecules molecules will will be be able able to to leave leave the the pores pores of of the the adsorbent adsorbent particles: particles: this this is is the the Desorption Desorption of of the the adsorbent. adsorbent. (also Regeneration)) (also called called Regeneration Thus, fixed adsorbent adsorbent quantity, quantity, we we design design aa cyclic cyclic process process Thus, for for aa fixed with with alternating alternating phases: phases: adsorption/desorption. adsorption/desorption. ¾we ¾we can can play play with with the the temperature: temperature: TSA TSA cycle cycle (Temperature (Temperature Swing Swing Adsorption) Adsorption) ¾we ¾we can can play play with with the the pressure: pressure: PSA PSA cycle cycle (Pressure (Pressure Swing Swing Adsorption). Adsorption). PERU LNG - 2009

7

Air Purification

Adsorbent Adsorbent characteristics characteristics

• The name of Adsorbents designates porous solid materials. • Their main characteristic is a maximum surface (active zone for the adsorption process) in a small volume: we define the specific area. • Adsorbents come in different forms: - spherical balls - cylindrical pellets - irregular crushed particles

ACTIVATED CARBON ALUMINA MOLECULAR SIEVE: Type A, Type X

Each gram of product particle has a surface equivalent to a tennis court Chimical formula

Specific area m2/g

Pore diameter Angström (10-10 m)

C

800 to 1500

40 to 5000

AL2O3

300 to 350

10 to 40

SiO2, Na2O CaO, K2O

900

3 to 10

PERU LNG - 2009

8

Air Purification

Selectivity Selectivity of of the the process process

Affinity (Adsorbent / Molecule) depends on : •• The The type type of of adsorbent: adsorbent: –– presence presence of of attraction attraction field field –– diameter diameter of of the the pores pores •• The The type type of of molecule: molecule: –– their their physical physical and and chemical chemical characteristics characteristics determine determine the the intensity intensity of of the the adsorbent adsorbent attraction: attraction: so, so, we we designate designate molecules molecules strongly strongly attracted attracted (with (with electrical electrical moment) moment) and and molecules molecules weakly weakly attracted attracted (neutral (neutral molecules) molecules) –– the the size size of of the the molecules molecules must must be be smaller smaller than than the the diameter diameter of of the the pores: pores: thus, thus, nitrogen nitrogen molecule molecule is is able able to to pass pass into into aa 44 Å Å pore, pore, but but not not into into aa 33 Å Å pore. pore. Adsorbed molecules ACTIVATED CARBON ALUMINA MOLECULAR SIEVE

Oil vapour: Hydrocarbons C2 and C3 types H2O C2H2, NO2, CO2, H20

PERU LNG - 2009

10

Air Purification

Choice Choice of of adsorbents adsorbents

The function of the adsorption process for an APSA unit is to trap in vapour form the air contaminants such as water, carbon dioxide CO2 and hydrocarbons, before feeding the cold box. To trap water, knowing that air is always saturated after compression process, the choice indifferently could be molecular sieve or alumina. We prefer alumina for the following reasons: - alumina is less sensitive to the possible presence of liquid water particles - the temperature of regeneration process for alumina is colder: around 40°C for alumina, 250°C for molecular sieve

ALUMINA ALUMINA HH2OO 2

To trap CO2, the only choice is molecular sieve. The same for hydrocarbons, mainly made up of acetylene C2H2: it is not possible to trap methane CH4 by the adsorption process.

MOLECULAR MOLECULAR SIEVE SIEVE CO CO22,,CC22HH22

PERU LNG - 2009

11

Air Purification

Adsorption: Adsorption: Water Water analogy analogy

Saturated Gas

ADSORPTION Dry gas

Saturated zone

front

Clean zone

DESORPTION (REGENERATION) Saturated Gas

Dry gas

END OF DESORPTION (REGENERATION)

PERU LNG - 2009

12

Air Purification

Installation Installation design design

The The design design of of the the installation installation is is aa combination combination with with two two types types of of adsorbents: adsorbents: •• first, first, compressed compressed air air passes passes through through aa bed bed of of alumina alumina in in order order to to trap trap water water •• then, then, compressed compressed air air passes passes through through aa bed bed of of molecular molecular sieve sieve intended intended to to trap trap CO and Hydrocarbons CO22 and Hydrocarbons Thus, Thus, we we keep keep molecular molecular sieve sieve free free of of moisture moisture contamination. contamination.

MOLECULAR SIEVE CO2, C2H2

MOLECULAR SIEVE

Adsorber V-6701 A/B

ALUMINA

ALUMINA H 2O

AIR

AIR PERU LNG - 2009

13

Air Purification Adsorption Adsorption // Regeneration Regeneration Cycle Cycle Using Using aa fixed fixed amount amount of of adsorbent, adsorbent, we we know know that that the the duration duration of of adsorption adsorption process process will will be be limited: limited: after after aa certain certain duration duration of of air air circulation, circulation, the the pores pores of of the the adsorbent adsorbent become become saturated: saturated: -- with with water water molecules molecules for for alumina alumina -- with and Hydrocarbon Hydrocarbon molecules molecules for for molecular molecular sieve sieve with CO CO22 and

We We obtain obtain the the saturation saturation of of the the adsorbents: adsorbents: the the adsorption adsorption process process is is over. over. Contaminant-free air

To To achieve achieve aa continuous continuous air air purification purification compatible compatible with with the the non-stop non-stop distillation distillation process process of of APSA APSA unit, unit, we we need need an an operating operating cycle cycle with with two two adsorbers. adsorbers.

Air with contaminants

REGENERATION ADSORPTION

An An arrangement arrangement with with two two adsorbers adsorbers in in parallel parallel allows allows to to purify purify compressed compressed air air with with one one adsorber adsorber (ADSORPTION (ADSORPTION phase), phase), while while the the second second one one is is in in desorption process (REGENERATION phase). desorption process (REGENERATION phase). When When the the first first adsorber adsorber is is close close to to the the limit limit of of adsorption adsorption capacity, capacity, we we perform perform aa reverse reverse operation operation in in order order to to feed feed with with compressed compressed air air the the second second adsorber, adsorber, which which is is contaminant-free contaminant-free thanks thanks to the previous regeneration process. to the previous regeneration process. PERU LNG - 2009

14

Air Purification

Adsorption Adsorption front front in in the the bed bed

Bed Height

Contaminant-free air

t = 100 min

Adsorbed quantity

t = 20 min 0 500

400

300

200

100

CO2 (ppm)

0

0

1

2

3

4

5

Adsorbed quantity

Air with contaminants

PERU LNG - 2009

15

Air Purification Regeneration Regeneration front front in in the the bed bed Regeneration fluid : Vaporized Rich Liquid (VRL)

Bed Height

Vaporized Rich Liquid

Desorbed quantity

0 500

400

300

200

100

CO2 (ppm)

0

0

1

2

3

4

5

Desorbed quantity

Saturated Vaporized Rich Liquid PERU LNG - 2009

16

Air Purification Adsorption Adsorption // Regeneration Regeneration Cycle Cycle Influence of pressure and temperature

Adsorbed quantity

T1 1 Pressure effect (depressurization) 2 Temperature effect (heating)

T2 > T1

3

Partial pressure

PERU LNG - 2009

17

Air Purification Air

Vaporized Rich Liquid

Technology Technology Regeneration Regeneration fluid fluid :: Vaporized Vaporized Rich Rich Liquid Liquid (VRL) (VRL) „ „

Horizontal Horizontal beds beds

Adsorption Adsorption phase phase :: ¾ ¾ Cycle Cycle time time :: 150 150 min min ¾ ¾ Air Air pressure pressure :: 8.1 8.1 bar bar gg ¾ ¾ Air Air temperature temperature :: 40°C 40°C „ „ Regeneration Regeneration phase phase :: ¾ ¾ Regeneration Regeneration temperature temperature :: 90°C 90°C (heater (heater outlet) outlet) ¾ ¾ Air Air pressure pressure :: 0.1 0.1 bar bar gg ¾ ¾ Heating Heating duration duration :: ~20 ~20 min min ¾ ¾ Cooling Cooling duration duration :: ~100 ~100 min min „ „

Mole Sieve bed Alumina bed

Air

Vaporized Rich Liquid

PERU LNG - 2009

18

Air Purification

V01 V01 // V02 V02 Installation Installation Electric heater EH-6701

Air to Cold Box

VRL CVWO009A

CVWO009B

CVAG06A

CVAG06B

KV 530

Regeneration Phase

V-6701 A

Event VRL

V-6701 Adsorption Phase B

KV 515

KV 525

KV 516

KV 526

KV 510

KV 520

Air PERU LNG - 2009

19

Air Purification

Purification Purification cycle cycle

Air

Purification steps

È HP Isolation È Depressurization È Blow-Off Bottle in Regeneration phase

VRL VRL

Bottle in Adsorption phase

È Heating È Cooling È LP Isolation È Pressurization È Parallel position

Air

È Adsorption

PERU LNG - 2009

20

Air Purification

Pressure Pressure cycle cycle

Air Bottle 1

Regeneration Heating

pressure

Adsorption

VRL VRL

Bottle in Adsorption phase

time

Bottle 2 Regeneration Heating

Cooling

Adsorption

pressure

Bottle in Regeneration phase

Cooling

time

Air

PERU LNG - 2009

21

Air Purification

VRL

Automatic Automatic sequence sequence

Cold Box

V6701 A

Event

V6701 B

Air

On line V6701 B HP Isolation V6701 A

VRL

V6701 A

Cold Box

Event

V6701 B

Air

Depressurization V6701 A

PERU LNG - 2009

22

Air Purification

VRL

Automatic Automatic sequence sequence

Cold Box

V6701 A

Event

V6701 B

Air

Blow-Off V6701 A

VRL

Cold Box

V6701 A

Event

V6701 B

Air

Heating V6701 A

PERU LNG - 2009

23

Air Purification

VRL

Automatic Automatic sequence sequence

Cold Box

V6701 A

Event

V6701 B

Air

Cooling V6701 A

VRL

Cold Box

V6701 A

Event

V6701 B

Air

LP Isolation V6701 A

PERU LNG - 2009

24

Air Purification

VRL

V6701 A

Automatic Automatic sequence sequence

Cold Box

Event

V6701 B

Air

Pressurization V6701 A

VRL

Cold Box

V6701 A

Event

V6701 B

Air

Parallel Position

PERU LNG - 2009

25

Air Purification

Temperature

Temperature Temperature profile profile

Inlet temperature

Heating temperature

Good Regeneration indicator

Outlet temperature Cold Desorption

Hot Desorption Heat Peak

VRL temperature at cold box outlet

Heating

Cooling

Time

PERU LNG - 2009

26

Air Purification What does the purification process look like ?

PERU LNG - 2009

27

Air Purification What does the purification process look like ?

PERU LNG - 2009

28

EXCHANGERS

PERU LNG - 2009

1

4. Heat Exchange „

4.1. Why exchange the heat ? Gaseous N2 to customer

Residual Enriched Gas (>35% O2)

R01

Liquid N2 to backup

R02 D01

Air inlet

K01

C01

Compression Purification

NON-CRYOGENIC

Cold Production

Heat Exchange

Distillation

CRYOGENIC PERU LNG - 2009

2

4. Heat Exchange „

4.2. Principles of Heat Exchange „

GOAL

DTo get air at good conditions for the distillation DTo warm up gaseous product from the cryogenic temperature to the ambient one

„

PRINCIPLES

DHeat flux from the Hot fluid to cold fluid DDriving force = temperature difference DCounter flow arrangement DHeat exchange in an aluminium brazed Heat Exchanger

PERU LNG - 2009

3

4. Heat Exchange „

4.3. Heat exchange formula

ΔH = K . S . Ln(ΔT) where

ΔH = Duty or Heat exchanged (kcal/h) K = Heat exchange coeff = f(fluids, material, flow) (kcal/h.m2.°C) S = Surface (m2) ΔT = Average temperature difference between hot and cold fluids (°C)

PERU LNG - 2009

4

4. Heat Exchange „

4.4. Heat exchange formula

ΔH = Q . Cp . ΔT where

ΔH = Duty or Heat exchanged (kcal/h) Q = Flowrate (Nm3/h) Cp = Specific heat (kcal/Nm3/°C) ΔT = Temperature difference for the same fluid (°C)

PERU LNG - 2009

5

4. Heat Exchange „

4.5.Three types of heat exchanger

+

+

Counter-current

+

+

Co-current

+

+

Cross current

PERU LNG - 2009

6

4. Heat Exchange „

4.6. Co-current exchanger Insulation

Cold Nitrogen Hot Nitrogen Cold Nitrogen

-100°C

-50°C

0°C

-50°C

-100°C

-50°C

Same number of hot passages and cold passages Temperature of Hot Nitrogen at the end of the exchanger ? PERU LNG - 2009

7

4. Heat Exchange „

4.7. Counter-current exchanger

Hot Nitrogen

-5°C

-10°C

-100°C

0°C

-5°C

-95°C

-5°C

-10°C

-100°C

Cold Nitrogen

Cold Nitrogen

Same number of hot passages and cold passages Temperature of Hot Nitrogen at the end of the exchanger ? PERU LNG - 2009

8

4. Heat Exchange „

4.8. ΔT Warm End definition Air

WN2

ΔT warm end

GAN

ΔT cold

Brazed aluminium HX ΔT cold = 0°C ΔT warm end ~ 2°C

Loss of cold capacity to be produced by the turbine

PERU LNG - 2009

9

4. Heat Exchange „

4.9. Basis about heat exchange diagram

-100

-95

si te

-100°C

0°C

-45°C

-95°C

-5°C

-50°C

-100°C

N2

N2

po

ΔT Warm End ?

co m

d l Co

m o c

po

te i s

-50°C

Ho t

Exchanged heat (kcal/h)

Air

-5°C

-5

0

Temperature (°C) PERU LNG - 2009

10

4. Heat Exchange „

4.10. Real heat balance diagram for APSA L ΔH Heat flow (kcal/h) 1400000

1200000

Hot composite 1000000

Cold composite

800000 600000

400000

200000

0 -200

-150

-100

-50

0

50

Temperature (°C) PERU LNG - 2009

11

4. Heat Exchange „

4.11. Heat balance QC T4

T1

Warm end

Cold end

T3

QF

Heat Balance :

T2

T4 T1

ΔH

T3

T

T2

ΔH = Q . Cp . ΔT ΔH = ΔHC = QC . CpC . ( T2 – T1 ) = - ΔHF = - QF . CpF . ( T4 – T3 ) PERU LNG - 2009

12

4. Heat Exchange „

4.12. Heat exchange exercise Warm end

„ We

consider a counter flow exchanger

8 Nm3/h 20°C

25°C

want to warm up 5 Nm3/h of N2 from - 100 to 20°C at 1 bar abs

„ We

8 Nm3/h flowrate of Air is available at 25°C and 5 bar abs

AIR

NITROGEN

„A

„ Cp(Air) „ Cp(N2)

-100°C 5

Nm3/h

T=?

„

= 0.31 kcal/Nm3/°C

= 0.31 kcal/Nm3/°C

Air temperature at cold end ?

Cold end PERU LNG - 2009

13

4. Heat Exchange „

4.13. Heat exchange exercise result Warm end 8 Nm3/h 20°C

25°C

„

Heat exchanged by Nitrogen ΔHN = 5x0.31x[20-(-100)] = 186 kcal/h

AIR

NITROGEN

2

-100°C

„

Heat exchanged by air ΔHAIR = 8x0.31x[T-25]

„

But ΔHN = - ΔHAIR = 186 kcal/h

„

Then 8x0.31x[T-25] = -186 kcal/h

„

Finally T = -186/(8x0.31)+25 = -50°C

2

T= -50°C

5 Nm3/h Cold end PERU LNG - 2009

14

4. Heat Exchange „

4.14. Influence of flowrate on heat exchange

Flow evolution

ΔT warm end

ΔT cold end

Hot fluid

Cold fluid

PERU LNG - 2009

15

4. Heat Exchange „

4.15. Influence of temperature on heat exchange

Temperature

ΔT warm end

ΔT cold end

Hot fluid

Cold fluid

PERU LNG - 2009

16

4. Heat Exchange „

4.16. Counter flow arrangement

Perforated fins

Heringbone fins

Spacer bar Parting sheet

Exchange fin

Spacer bar

Serrated fins

Flowrate Parting sheet PERU LNG - 2009

17

4. Heat Exchange „

4.17. Different flow arrangements

PERU LNG - 2009

18

4. Heat Exchange „

4.18. Different type of distributors

PERU LNG - 2009

19

4. Heat Exchange „

4.19. Different type of fins

Straight fins

Serrated fins

Perforated fins

Heringbone fins PERU LNG - 2009

20

4. Heat Exchange „

4.20. General view of the heat exchanger

1

8 7

4 3

10 6

11 9

12

14

1 3 15

5 2

1

- Assembly

6

- Width

10

- Side plate

2

- Outlet fluid

7

- Stack

11

- Parting sheet

3

- Core

8

- Length

12

- Heat transfer fins

4

- Header

9

- Passes

13

- Distributor fins

5

- Nozzle

14

- Spacer bar

15

- End bar PERU LNG - 2009

21

4. Heat Exchange „

4.21. General view of the heat exchanger

PERU LNG - 2009

22

4. Heat Exchange „

4.22. Warm end Embrittlement hazard

„

Nitrogen piping at warm end of the Heat Exchanger is not designed for cryogenic temperature

„

Occasionally, there can be cold fluid ingress at the warm end : DDuring process deviation DDuring stop of the plant

„

Precautions must be taken to prevent cold embrittlement

PERU LNG - 2009

23

COLD PRODUCTION

PERU LNG – 2009

1

6. Cold Production „

6.1. Energy balance principle

Σheat (inlet ) = Σheat (outlet )

Heat inlet or Cold losses

APSA-L

Heat losses or Cold inlet

PERU LNG – 2009

2

6. Energy Balance & Cold Production „

6.2. Cold balance application Warm end ΔT

0.1 bar g 35°C

7 bar g -171°C GAN

LIN

Liquid production

ΔΤ{

R01

R02

Insulation losses

D01

Air inlet

K01

C01

Turbine work 8 bar g 40°C PERU LNG – 2009

3

6. Cold Production „

6.3. Energy balance „

Cold losses or heat inlets

DHeat exchanger warm end temperature difference DLiquid production DHeat entrance due to non perfect insulation „

Cold inlets or heat losses

DTurbine work DIsotherm expansion of products DLiquid assist

PERU LNG – 2009

4

6. Cold Production „

6.4. Cold balance comparison

Small units GAS

LIQUID

Large plants GAS

LIQUID

Insulation

70%

7%

20%

1%

Warm end ΔT

30%

2%

80%

3%

0%

91%

0%

96%

Liquid production

PERU LNG – 2009

5

6. Cold Production „

6.5. Why a Cold Production is required ? „

AIM

DSTART-UP: COOL DOWN To ensure a decrease of the temperature in the cold box DNORMAL RUN: ENERGY BALANCE To maintain the cold balance of the plant

„

HOW

DBy withdrawing some heat out of the cryogenic system DBy expansion of air

PERU LNG – 2009

6

6. Cold Production „

6.6. Turbine principle Symmetric Symmetricwork workto tothe theone oneof ofaacentrifugal centrifugalcompressor compressor

Compresseur

Turbine

PERU LNG – 2009

7

6. Cold Production „

6.7. Turbine thermo-dynamical Principle

Theorem of Bernoulli :

P V² + − E = cste ρ 2

Static pressure Compressor / Pump

Dynamic pressure Turbine

PERU LNG – 2009

8

6. Cold Production „

6.8. Turbine thermodynamical Principle

Increase in the gas’ speed without energy extraction in the inlet vanes (1) ⇒ static pressure diminishes

2 1

3

Decrease in the gas’ speed with energy extraction in the relaxation wheel (2) ⇒ dynamic pressure diminishes Decrease in the gas’ speed without energy extraction in the diffuser (3) ⇒ dynamic pressure is transformed into static pressure PERU LNG – 2009

9

6. Cold Production „

6.9. Turbine overview

Entrance gas process

Outing g as

process

Turbine body

PERU LNG – 2009

10

6. Cold Production „

6.10. Turbine wheels Gas outing

Gas entrance

PERU LNG – 2009

11

6. Cold Production „

6.11. Turbine wheels

Wheel of the turbine

Discharge

Adjustable diffuser (IGV)

Arrival of the fluid by the volute

PERU LNG – 2009

12

6. Cold Production „

6.11. Speed triangle Fixed part : Distributor 0

r U1

r W1

1

r r U r V2 2 W2

0

r V1

1 2 3

2

Mobile guide vanes ⇒ Wheel

PERU LNG – 2009

13

6. Cold Production „

6.12. How braking cryogenic turbines ? Production of mechanical energy with the expansion wheel

Energetic stability ⇒ Consumption of this energy

Braking of the turbine

Electrical generator

Oil spin-dry pump

Oil brake

Air brake

Booster brake

PERU LNG – 2009

14

6. Cold Production „

6.13. APSA-L Oil brake turbine principle

Oiled contact surface

Turbine wheel - Figure of an oil brake PERU LNG – 2009

15

6. Cold Production „

6.14. APSA-L cold production equipment

Air Water Air

Oil Tank

PERU LNG – 2009

16

6. Cold Production „

6.15. APSA-L PERU LNG : LIN Production Case

F = 1650 Nm3/h P = 4.3 bar g T = -148°C

LRV Turbine

F = 1650 Nm3/h P = 0.2 bar g T = -184°C

-19 kW

19 kW

S = 43000 rpm PERU LNG – 2009

17

6. Cold Production „

6.16. Cryostar ECO turbine

Oil tank

Oil brake valve PERU LNG – 2009

18

6. Cold Production „

6.17. Cryostar ECO turbine Oil pump

Oil tank

Oil cooler

PERU LNG – 2009

19

6. Cold Production „

6.18. Turbine elements

Expander stage

Oil brake sleeve in bearing housing PERU LNG – 2009

20

6. Cold Production 6.19. Expansion turbine behaviour „

2 choices to increase the cold production of the plant: Dincrease the turbine inlet pressure of 100 mbar Ddecrease the turbine outlet pressure of 100 mbar

„

What is the best choice ? EXPANSION POWER VARIATION VS P VARIATION EITHER ON MP SIDE OR BP SIDE 16.1 16

Conclusion

15.9

Be careful with the pressure on the BP side of the turbine. Quick loss of cold production

15.8 15.7 Power (kW)

„

15.6

POWER BP VAR (KW) POWER MP VAR (kW)

GAIN BP

15.5 15.4

GAIN MP

15.3 15.2 15.1 15 0

10

20

30

40

50

60

70

80

90

100

DP (mbar)

PERU LNG – 2009

21

6. Cold Production „

6.20. P&ID : Expansion turbine

PERU LNG – 2009

22

AIR DISTILLATION PRINCIPLE

PERU LNG -2009

1

Distillation Goal and principle „

GOAL

DTo separate Nitrogen and Oxygen from atmospheric Air „

PRINCIPLE

DSeparation by Distillation : Content difference between liquid and vapour phases „

KEY PARAMETERS

DBoiling Point DLiquid vapour equilibrium DFractional distillation DReflux

PERU LNG -2009

2

Distillation

PRINCIPLE PRINCIPLE

WATER + ALCOHOL MIXTURE: ALCOHOL: most volatil component WATER: least volatil component VAPOUR: enriched in most volatil component:

ALCOHOL

LIQUID: enriched in least volatil component:

LIQUID Mixture Two components:

WATER + ALCOHOL

BOILING APSA03/Distill1/VA#1

WATER PERU LNG -2009

3

Distillation

PRINCIPLE PRINCIPLE

AIR = MIXTURE NITROGEN (79 %) + OXYGEN (21 %) most volatil component : NITROGEN least volatil component : OXYGEN VAPOUR: enriched in most volatil component:

NITROGEN

LIQUID AIR -200°C, 1 b abs

LIQUID: enriched in least volatil component:

BOILING APSA03/Distill1/VA#2

OXYGEN PERU LNG -2009

4

Distillation

Boiling éfinition Boiling Point Point ddéfinition

At Atthe theboilling boillingpoint, point,there thereare aretwo twophases: phases: --aaboiling boilingLIQUID LIQUID --aarelease releaseof ofVAPOUR VAPOUR AAboiling boilingpoint pointis isdefined definedwith: with: --aaTEMPERATURE TEMPERATURE TT --aaPRESSURE PRESSURE PP

VAPOUR Thus Thuswe wedefine defineaa LIQUID-VAPOUR LIQUID-VAPOUREQUILIBRIUM EQUILIBRIUM

P, T LIQUID

PERU LNG -2009

5

Distillation

Boiling Boiling Points Points Boiling point values and volatility scale

Name

Symbol

Molecular Weight (g)

Boiling Temperature @ 1,013 bar abs.

Helium Hydrogen Neon Nitrogen Air Argon Oxygen Kripton Xenon

He H2 Ne N2 Air Ar O2 Kr Xe

2 2 20 28 29 40 32 84 131

-269 °C -253°C -246°C -196°C -191°C -186°C -183°C -153°C -108°C

PERU LNG -2009

6

Distillation

Boiling Boiling Points Points

At the boiling point, if one parameter changes (Pressure or Temperature), the other parameter has to change too:

NITROGEN VAPOUR

LIQUID

VAPOUR LIQUID

VAPOUR LIQUID

OXYGEN

1 b abs - 196 °C

VAPOUR

3.6 b abs - 183 °C

VAPOUR

11 b abs - 168 °C

LIQUID

LIQUID

VAPOUR

LIQUID

1 b abs - 183 °C

3.6 b abs - 168 °C

11 b abs - 152 °C PERU LNG -2009

7

Distillation

Boiling Boiling Points Points Curves Curves

PRESSURE AND TEMPERATURE RELATIONSHIP: •If the Pressure increases, the Temperature has to increase too OR •If the Temperature increases, the Pressure has to increase too AND inversely.

D’où les courbesthe des points d’ébullition: Consequence: boiling point curves 4

Pressure = f (Temperature)

P

Temperature = f (Pressure)

T

Liquid State

Gaseous State

Gaseous State

Liquid State

P

T

Curves: Liquid state and Gaseous state separation APSA03/Distill1/VA#6

PERU LNG -2009

8

Distillation

Boiling Boiling Points Points Nitrogen versus Oxygen 4.5 b abs

1.3 b abs

VAPOUR

VAPOUR

LIQUID

LIQUID

- 183 °C - 196 °C NITROGEN NITROGEN NITROGEN

OXYGEN

1 b abs ISOBARIC ISOBARIC

OXYGEN OXYGEN

- 180 °C ISOTHERMAL ISOTHERMAL Nitrogen Nitrogen is is more more volatil volatil than than Oxygen Oxygen:

-NITROGEN -NITROGEN == most volatile component -OXYGEN -OXYGEN == least volatile component PERU LNG -2009

9

Distillation

Nitrogen Nitrogen -- Oxygen Oxygen mixture mixture

For Foran anOXYGEN-NITROGEN OXYGEN-NITROGENMIXTURE MIXTUREat atthe theLIQUID-VAPOUR LIQUID-VAPOUR EQUILIBRIUM, EQUILIBRIUM,

NITROGEN NITROGENbeing beingthe themost mostvolatile volatilecomponent: component:

--the thevapour vapourphase phaseBECOMES BECOMESENRICHED ENRICHED IN INNITROGEN NITROGEN

- -the theliquid liquidphase phaseBECOMES BECOMESLESS LESS CONCENTRATED IN NITROGEN: CONCENTRATED IN NITROGEN:

P, T

O2+N2

O2+N2

CONSEQUENTLY, CONSEQUENTLY,IT ITBECOMES BECOMES ENRICHED IN OXYGEN ENRICHED IN OXYGEN

(the (theVapour Vapourphase phaseand andthe theLiquid Liquidphase phaseare arecalled calledCONCOMITANT CONCOMITANTPHASES) PHASES) PERU LNG -2009

10

Distillation

Fractional Fractional Distillation Distillation VAPOUR even more enriched in NITROGEN CONDENSER

VAPOUR: enriched in NITROGEN

2d BOILING LIQUID: enriched in OXYGEN

1st BOILING

Liquefaction: Liquid enriched in NITROGEN

PERU LNG -2009

11

Distillation

Fractional Fractional Distillation Distillation VAPOUR: "PURE" NITROGEN

Successive Boilings and Liquefactions

R

UR O P VA

R MO

LIQUID: "PURE" OXYGEN

MO D N A E

ITR N N DI E ICH R N EE

LIQ

EN G O

EN G XY O IN D HE ty) C I vi R a N r E E by g R MO own D N sd A w RE id flo O M iqu D l I ( U

APSA03/Distill1/VA#10

PERU LNG -2009

12

Distillation

Fractional Fractional Distillation Distillation

ISOBARIC ISOBARIC SYSTEM: SYSTEM: pressure pressure is is the the same same in in each each vessel vessel e.g.: e.g.: 11 b b abs abs

- 196 °C "PURE" NITROGEN

CONSEQUENCE: CONSEQUENCE: TEMPERATURE TEMPERATURE GRADIENT GRADIENT

- 183 °C "PURE" OXYGEN APSA03/Distill1/VA#11

PERU LNG -2009

13

Distillation

LIQUID LIQUID –– VAPOUR VAPOUR CONTACT CONTACT

SUPPRESSION OF THE BOILERS AND CONDENSERS Vapour: HOTTER

For that, we achieve a LIQUID-VAPOUR CONTACT: the Vapour passes through the Liquid in the vessel

Liquid: COLDER

- the vapour HOTTER, makes the liquid boiling - the liquid COLDER, condenses the vapour

LIQUID

Boiling of the LIQUID = VAPOUR

(colder)

LIQUID-VAPOUR Contact

Heat Transfer (calories)

LIQUID-VAPOUR CONTACT VAPOUR

Liquefaction of the VAPOUR = LIQUID

(hotter)

APSA03/Distill1/VA#12

PERU LNG -2009

14

Distillation

LIQUID LIQUID –– VAPOUR VAPOUR CONTACT CONTACT

SUPPRESSION OF THE BOILERS AND CONDENSERS

CONDENSER

We We only only need: need: •One •One boiler boiler at at the the bottom bottom •One •One condenser condenser at at the the top top

TE

T: N DIE A GR ter E t UR is ho lder T RA pour is co E MP Va id u Liq

BOILER PERU LNG -2009

15

Distillation Fractional Fractional Distillation Distillation :: Columns Columns CONDENSER

LIQUID BECOMES RICHER IN LEAST OLATILE COMPONENT

LIQUID-VAPOUR CONTACT CONTACT LIQUID-VAPOUR

LABORATORY LABORATORY Device Device

VAPOUR BECOMES RICHER IN MOST VOLATILE COMPONENT

MOST VOLATILE COMPONENT

DISTILLATION DISTILLATION COLUMNS: COLUMNS: TRAYS TRAYS PACKING PACKING

LEAST VOLATILE COMPONENT

BOILER: Vaporizer PERU LNG -2009

16

Distillation

Regular Regular Column Column

CONDENSER

Condenser LIN DRAW-OFF

GAN DRAW-OFF

Σ

GAN LIN

GOX DRAW-OFF

VAPOUR LIQUID = REFLUX

AIR FEED

PACKING SECTIONS

AIR

GOX

Σ

LOX DRAW-OFF VAPORIZER

Vaporizer LOX PERU LNG -2009

17

Distillation Volatility scale

He H2 Ne N2 Ar O2 Kr Xe CnHm

Air Air Components Components breakdown breakdown

NITROGEN HELIUM HYDROGEN NEON

AIR : NITROGEN OXYGEN ARGON HELIUM KRYPTON NEON XENON HYDROGEN CnHm

OXYGEN ARGON KRYPTON XENON CnHm

PERU LNG -2009

18

Distillation

From From the the regular regular column column to to the the APSA APSA

FOR A GAS NITROGEN PRODUCTION, ONLY THE UPPER SECTION OF THE COLUMN IS NECESSARY: we do not need the lower section CONDENSER

GAN DRAW-OFF

CONDENSER

VAPOUR

GAN DRAW-OFF

LIN DRAW-OFF

AIR FEED

LIQUID

AIR FEED

LIN DRAW-OFF

GOX DRAW-OFF LOX DRAW-OFF

VAPORIZER

PERU LNG -2009

19

Distillation

From From the the regular regular column column to to the the APSA APSA CONDENSER

GAN DRAW-OFF

EQUIPMENTS NEEDED: - PACKING SECTION - CONDENSER AT THE TOP - AIR FEED IN GASEOUS STATE

PACKING SECTION

- GAN DRAW-OFF - LIQUID WASTE OUTLET

AIR FEED

Air feed must be in gaseous state,

in order to build-up the up-coming vapour:

LIQUID WASTE OUTLET

so that, the vaporizer is no longer necessary PERU LNG -2009

20

Distillation

Material Material Balance Balance

INCOMING INCOMING MATERIAL MATERIAL QUANTITY= QUANTITY= OUTGOING OUTGOING MATERIAL MATERIAL QUANTITY QUANTITY

400 Nm3/h

THE THELIQUID LIQUIDWASTE WASTEIS ISTHE THE CONSEQUENCE OF THE MATERIAL CONSEQUENCE OF THE MATERIAL BALANCE: BALANCE: Flowrate, Flowrate,O2 O2content content ITS ITSO2 O2CONTENT CONTENTIS ISALWAYS ALWAYSHIGHER HIGHER THAN THE ONE OF AIR; THAN THE ONE OF AIR; For Forthat, that,this thisliquid liquidisiscalled: called:

1000 Nm3/h O2 = 21 %

RICH RICHLIQUID LIQUID

Flowrate = 1000 - 400 = 600 Nm3/h 1000 x 21 % O2 = = 35 % 600

PERU LNG -2009

21

Distillation VAPORIZATION VAPORIZATION vs vs LIQUEFACTION LIQUEFACTION • VAPORIZATION 1 kg Liquid

1 kg Vapour

heat quantity SUPPLY

• LIQUEFACTION

1 kg Liquid

1 kg Vapour

heat quantity DRAW-OFF

APSA03/Distill2/VA#4

PERU LNG -2009

22

Distillation LATENT LATENT HEAT HEAT OF OF VAPORIZATION VAPORIZATION DEFINITION: Heat quantity necessary to vaporize totally 1 kg of liquid

1 kg Vapour

1 kg Liquid

Heat quantity: kcal

OXYGEN: OXYGEN: 51 51kcal kcal(-183 (-183°C, °C,11bbabs) abs) NITROGEN: NITROGEN: 47.6 47.6kcal kcal(-196 (-196°C, °C,11bbabs) abs)

APSA03/Distill2/VA#5

PERU LNG -2009

23

Distillation

Vaporizer Vaporizer -- Condenser Condenser system system

• OBJECTIVES:

CONDENSER

To liquefy gas nitrogen at the top of the column in order to achieve the Reflux.

GAN

LIN

• PRINCIPLE: We need a specific device to draw-off the connecting heat quantity from gas nitrogen. Heat quantity DRAWN-OFF

GAN

LIN PERU LNG -2009

24

Distillation

Vaporizer Vaporizer -- Condenser Condenser system system

• PRINCIPLE: In In an an EXCHANGER, EXCHANGER, we we achieve achieve an an HEAT HEAT TRANSFER TRANSFER (CALORIES) (CALORIES) between between GAS GAS NITROGEN NITROGEN and and RICH RICH LIQUID LIQUID CONSEQUENCES: CONSEQUENCES: -- Gas Gas Nitrogen Nitrogen becomes becomes liquefied liquefied (heat (heat quantity quantity draw-off) draw-off) -- Rich Rich Liquid Liquid becomes becomes vaporized vaporized (heat (heat quantity quantity supply) supply)

Vaporized

RL

RL

GAN

Heat TRANSFER

LIN

PERU LNG -2009

25

Distillation

Vaporizer Vaporizer -- Condenser Condenser system system Upper part

Vaporized

RL

GAN

RL Heat TRANSFER

Vaporized RICH LIQUID

LIN

AN EXCHANGER IS LOCATED AT THE TOP OF THE COLUMN IN ORDER TO ACHIEVE THE HEAT TRANSFER BETWEEN RICH LIQUID AND GAN

EXCHANGER

RICH LIQUID bath GAN

LIN

APSA column PERU LNG -2009

26

Distillation

APSA APSA column column :: final final construction construction

VAPORIZED RICH LIQUID RICH LIQUID VALVE VAPORIZER - CONDENSER E02 RICH LIQUID BATH

GAN DRAW-OFF

K01

RICH LIQUID PIPE

GASEOUS AIR BOTTOM RICH LIQUID

PERU LNG -2009

27

Distillation

Reflux Reflux Ratio Ratio R R :: definition definition

GAN

L

V

L R= V Where: V = Vapor Flowrate (Nm3/h) L = Liquid Flowrate (Nm3/h)

AIR RL

PERU LNG -2009

28

Distillation

Reflux Reflux Ratio Ratio R R :: definition definition

L R= V

GAN GAN

Where:

V

L

L = V – GAN and

V = Air AIR

Consequently, R = f (GAN & Air flow rates) : AIR

R= LR

Air – GAN Air PERU LNG -2009

29

Distillation

Reflux Reflux Ratio Ratio R R variation variation

Incomming N2 amount Air

Outgoing N2 amount GAN

L/V

RL

Total

1000x79% = 400x100% = 400 790

600x65% = 390

790

1000x79% = 450x100% = 450 790

390

840

390/790= 0.49

GAN

340/790= 0.43

The column becomes less concentrated in Nitrogen : Consequently, the column becomes enriched in Oxygen

AIR The GAN purity decreases (O2 content increase)

LR

PERU LNG -2009

30

Distillation

Conclusion Conclusion :: Reflux Reflux Ratio Ratio impact impact

GAN

L

GAN R = L/V

V

% N2 GAN (GAN Purity)

AIR RL

PERU LNG -2009

31

Distillation

„

TECHNOLOGY TECHNOLOGY :: Packing Packing element element

AST (Advanced Sieve Trays)

DBenefits : • • • • •

Very efficient liquid vapour contact Low pressure drop (liquid film distribution) High operating flexibility (minimal / maximal gas load) High capacity (maximal gas load) Low inertia PERU LNG -2009

32

Distillation

TECHNOLOGY TECHNOLOGY :: Packing Packing element element

Structure: assembly of corrugated metallic sheets (aluminium).

PERU LNG -2009

33

Distillation

TECHNOLOGY TECHNOLOGY :: Packing Packing element element

The Liquid-Vapour contact is obtained by the division of the liquid on the corrugated-crossed sheets: the liquid film is drawn downwards by gravity while the gas (vapour) flows upwards through the perforations and the void spaces between the sheets.

Corrugatedcrossed aluminium sheets

Perforations

PERU LNG -2009

34

Distillation

Vaporizer Vaporizer Vaporizer Vaporizer -- Condenser Condenser

„

„

GOAL Dto condense gas at the top of the distillation column in order to ensure a liquid reflux in the column Dto vaporise Rich liquid fluid at a lower pressure in order to feed the turbine (APSA L/LE) or the booster (APSA LE)

GAN

PRINCIPLES DHeat exchange in an aluminium brazed Heat Exchanger DCounter flow arrangement DHeat flux from the Hot fluid to cold fluid DDriving force = temperature difference

AIR LR

PERU LNG -2009

35

Distillation

Vaporizer Vaporizer

E02 Vaporizer Vaporized RICH LIQUID -172°C

„

TECHNOLOGY : Bath type vaporiser

„

KEY COMPONENT FOR THE PRESSURE MAP AND FOR THE COLD PRODUCTION

„

SAFETY : in all cases the vaporiser must

be completely submerged

4.8b

RL + VRL

EXCHANGER T= 2°C RICH LIQUID bath

GAN

Incondensable gases

GAN

GAN -170°C LIN

9.7b LIN

APSA column

LIN RL PERU LNG -2009

36

Distillation

„

Vaporizer Vaporizer deconcentration deconcentration purge purge

AIR downstream the Air Purification still Contents some contaminants:

DHYDROCARBONS DN2O

„

A PART OF THESE COMPONENTS ARE STOPPED IN THE PURIFICATION UNIT

„

THE OTHER PART ENTER IN THE COLD BOX

DThe light components go up (ex: H2,…) DThe heavy component go within the vaporiser bath (RL)

PERU LNG -2009

37

Distillation

Vaporizer Vaporizer deconcentration deconcentration purge purge

„

AMONG THESE HEAVY COMPONENTS, SOME ARE NOT VAPORISED

„

CONCLUSION : WITHOUT ANY PURGE IT COULD HAPPEN AN ACCUMULATION OF HYDROCARBONS WHICH CAN FORM EXPLOSIVE COMPLEXES WITH RICH LIQUID BATH

„

TO AVOID ACCUMULATION, THE BATH MUST BE PURGED PERMANENTLY

„

DECONCENTRATION PURGE :

DDIRECTLY LINKED TO THE SAFETY OF THE PLANT

PERU LNG -2009

38

MASS BALANCE

PERU LNG – 2009

1

7. Mass balance „

7.1. Mass balance formula

Σ (inlet ) = Σ (outlet ) Residual Gas

AIR

APSA L

GAN

„ GLOBAL

MASS BALANCE

„ PARTIAL

MASS BALANCE

Σ inlet flowrate = Σ outlet flowrate Σ inlet flowrate,i = Σ outlet flowrate,i Σ inlet N flowrate = Σ outlet N flowrate 2

2

PERU LNG – 2009

2

7. Mass balance „

7.2. Mass balance application

Residual Gas

„ GLOBAL

MASS BALANCE

QAir = QRes + QGAN „ PARTIAL

AIR

APSA L

MASS BALANCE

QN2,Air = QN2,Res + QN2,GAN xAir.QAir = xRes.QRes + xGAN.QGAN

GAN

where

QAir = inlet air flowrate xAir = inlet air Nitrogen composition PERU LNG – 2009

3

7. Mass balance „

7.3. Mass balance exercise „A

customer want to produce N2 at a purity of 1ppm O2.

Residual Gas

„ He

wants to use his air network producing 4000 Nm3/h.

„A

AIR

APSA L

classical O2 content in the Residual gas is 30 % for such a plant.

„ Argon

is not considered in the calculation

GAN

„ How

„ Air

composition : 78.11 % N2, 0.93% Ar, 20.96% O2

much Nitrogen he will produce in these conditions ? PERU LNG – 2009

4

OVERVIEW OF APSA L CONTROL

PERU LNG – 2009

1

9. Process Flow Diagram : Warm Skid

PERU LNG – 2009

2

9. Process Flow Diagram : Cold Box

PERU LNG – 2009

3

9. Process Flow Diagram : LIN Storage

PERU LNG – 2009

4

GENERAL SAFETY

PERU LNG - 2009

1

Safety issues on APSA-L

„

General Safety Issues DGeneral hazards in industrial environment DHazards specific to ASU

„

CnHm related hazards DIdentification DPrevention

PERU LNG - 2009

2

General Safety Rules „

What kind of risks ? DRunning machines DElectricity DPressure DNoise DUnder-oxygenation (Anoxia) DOver-oxygenation DCryogenic temperatures DHigh temperatures DBurning

PERU LNG - 2009

3

Example: Pressure hazard THE DANGER FROM PRESSURISED EQUIPMENT IS DUE TO THE QUANTITY OF ENERGY STORED IN THE DEVICE TO COMPRESS THE FLUIDS IT CONTAINS.

RGY CAN BE CONSIDERABLE!

THIS ENE

IN CASE OF RUPTURE: THIS ENERGY CAUSES ABRUPT EXPANSION OF THE FLUID.

LEAK AND BURSTING

EXPLOSION 31

PERU LNG - 2009

4

Example: Pressure hazard (continued) PIPING AND CONTAINERS COMPLIANT WITH CURRENT REGULATIONS

-> Design codes -> Scheduled inspections -> Tests

ALWAYS MAKE SURE THERE IS ZERO PRESSURE BEFORE SERVICE OPERATIONS

SAFETY MEASURES OBSERVE SERVICE OPERATION PROCEDURES

SAFETY DEVICES

REPORT ANY DEFECT OBSERVED ON A DEVICE, A PIPE OR SAFETY PART IMMEDIATELY

32

PERU LNG - 2009

5

General Safety Rules

„

Usual Hazardous works : D Work at high levels D Digging work D Hoisting and handling equipments D Traffic D Electricity D Machines D Work on piping or vessel D Welding D Sources of radioactivity

PERU LNG - 2009

6

General Safety Rules „

Safety Management

Defining clearly responsibilities „ Approvals and qualifications „

DQualified and trained workers DQualified subcontractors „

Procedures DWork permit DElectrical / Mechanical isolation

„

Equipments DPPE DCertified tools / machinery

„

EIS Management?

PERU LNG - 2009

7

General Safety Rules

„

Usual Personal Safety equipment D Helmet D Safety glasses and adequate face shields for specific hazards (chipping, acid work, welding, molten metals …) D Ear plugs and noise-proof head sets D Safety shoes D Clean and Fire-proof clothing D Safety mittens or gloves D Protective masks with suitable filter D Safety belt or harness if necessary

PERU LNG - 2009

8

ASU Related Safety „

Gas Hazards

Processed gases of ASU involve 2 main specific hazards 1) Inflammation or explosion 2) Anoxia „

Inflammation or explosion D Causes • •

Presence of flammable gas in air Oxygen enriched atmosphere (more than 21% oxygen)

D Concerned zones • • • •

liquid oxygen filling station oxygen expansion valve station oxygen metering station liquid or gaseous oxygen vent PERU LNG - 2009

9

O2 gas hazard PROPERTIES

.GAS ENABLES AND MAINTAINS COMBUSTION.

SAFETY MEASURES

No leaks

DETECTION O 2%

COLOUR

After analysis

WITH AIR

if O 2 = 21%

NAME

IDENTIFICATION of pipes and storage locations.

Purge venting to the outside

PERU LNG - 2009

10

O2 gas hazard (continued) OXYGEN O 2 PERCEPTION DENSITY/AIR

Colourless, odourless, tasteless. d = 1.1

SPECIAL PRECAUTIONS

AIR

NORMAL PROPORTION IN AIR

21%

Detection with alarm if % O2 in air exceeds 25%. No grease, no oil.

EFFECT OF OXYGEN ENRICHMENT ON COMBUSTION Fuels ignite more easily. Flames much hotter and spread more quickly % O2 in air

25% 30% 50%

Effect on combustion

No particles. Clean clothing made from fire resistant textiles Controlled speed with slow manoeuvres.

FASTER COMBUSTION QUICK COMBUSTION

Floors clean and made from non combustible materials.

INSTANTANEOUS COMBUSTION EXPLOSION

PERU LNG - 2009

11

ASU Related Safety „

Gas Hazards „

Anoxia D 2 types • Sudden : less than 6% O2, victim falls down immediately • Slow : different steps, deeper breath, heart beats, no attention, thinking wrong, no fell pain ….

D Causes •

Gas containing not enough oxygen under an assimilable form by the human body

D Concerned zones • • • • • •

Inner cold box & Outer cold box Confined area or insufficiently ventilated Analysers rooms, or cabinets, control room Trenches or low points (sewer, pits…) When using cryogenic liquids (nitrogen, argon …) In vessels of the purification unit (desorption of beds) PERU LNG - 2009

12

N2 gas hazard Normal breathing

PROPERTIES

21% O2

Vertigo, headaches

GAS DOES NOT SUPPORT LIFE. WHEN THESE GASES ARE PRESENT: THE QUANTITY OF O2 DECREASES, ATMOSPHERE UNDER OXYGENATED, ASPHYXIA.

18% O 2 Asphyxia

0% O 2

SAFETY MEASURES DETECTION

No leaks

Alarm if O <18%

or

After analysis if O 2= 21%

If O2 < 18%

2

COLOUR

WITH AIR

NAME

IDENTIFICATION of pipes and storage locations.

Purge venting to the outside

PERU LNG - 2009

13

ASU Related Safety „

Cold Hazards

„

General D Liquefied gas concentrates in a small volume big amount of matter

„

Effects D Every touch with liquefied gas causes frostbite similar to burn D Skin and lungs can be damaged by cold atmosphere D Lower the temperature, longer the touch, more serious effects are D Hypothermia can cause death

„

Safety rules D Do not touch cold material D Do not stay in a cold atmosphere D Do not walk in a zone where cryogenic liquid has flown D Do not purge voluntarily cryogenic liquids on the ground D Take care of wet clothes PERU LNG - 2009

14

ASU Related Safety „

Operating in Heat Insulated Area „

Perlite Insulation (cold box, exchanger box) D Perlite : hydrated silicate pre-submitted to an expansion D Highly irritant material to be handled with gloves, glasses and mask D Extremely light and fluid (a fall in perlite lead to death)

„

Rock-wool insulation (cold tank, exchanger box) D Highly itching material D Work in a tunnel highly dangerous (risk of collapsing)

„

Nearly all heat insulated area are considered CONFINED SPACE Î specific entry rules apply

PERU LNG - 2009

15

HYDROCARBONS SAFETY

PERU LNG 2009

1

Hydrocarbons Safety

„ 1.

CnHm Hazards: Explanations

D 1. Risks related to the impurities in the bath type vaporizers D 2. Right/wrong operation of the E02 vaporizer D 3. Right/wrong operation of the front end purification (FEP)

„ 2.

Hazards Controls:

DThe 8 Golden Rules

PERU LNG 2009

2

Hydrocarbons Safety „

Some characteristics of the main impurities present in the atmosphere Impurity

Formula

Normal

Solubility

Inflamability Equilibrium

content

Limit in LOX

limit

coefficient K

in air

at - 181°C

in O2

in LOX

in ppm

in ppm

in ppm

at - 181°C

Methane

CH4

<5

no second phase

54000

0.3

Ethane

C2H6

< 0,5

128 000-250 000

30000

5,2 E-5

Ethylene

C2H4

< 0,5

13 000-30 000

27000

2,0 E-3

Acetylene

C2H2

< 0,5

4-6

25000

3,4 E-2

Propane

C3H8

<1

9 800

21000

5,0 E-7

Propylene

C3H6

<1

3 600 - 6 700

21000

5,0 E-6

n Butane

nC4H10

<1

700

18000

1,3 E-10

Carbon dioxide

CO2

< 400

4-5

3,3 E-3

Nitrous oxide

N2O

< 0,6

140 - 160

7,0 E-4

O3

< 0,1

no second phase

Ozone

PERU LNG 2009

3

Hydrocarbons Safety „

Bath type vaporizer operation (APSA-L)

Internal type (main vaporiser E02) LRV

LP

Important RECIRCULATION of liquid (thermosiphon effect): - around 1 Nm3 vaporised * Rare gases purge Ne, He, H2

- for 50 Nm3 of non-vaporised LR *

LR Purge

GAN & LIN Prod.

HP

* figures corresponding to an exchanger completely immersed PERU LNG 2009

4

Hydrocarbons Safety „

Proper and Wrong operation of a bath type vaporizer Normal operation Gas = 100 Nm3/h + Liq = 5000 Nm3/h N20 = 41 ppm

Reduced feed Liq = 25 Nm3/h N2O = 160 ppm

Gas = 100 Nm3/h N20 =100 ppb

DEPOSIT N2O

Heat to vaporise 100

Liq = 5100 Nm3/h N20 = 40 ppm

Heat to vaporise 100

Liq = 125 Nm3/h N20 = 40 ppm * * considering CO2 in that case, only 1 ppm in the feed would lead to deposit PERU LNG 2009

5

Hydrocarbons Safety „

Proper and Wrong operation of a bath type vaporizer CORRECT VAPORISATION

DRY VAPORISATION GAS LIFT STOPPED

TOO LOW LEVEL Gas lift in normal operation. Recycling = up to 50 times the vaporised flowrate

Solubility limit is reached. Deposits of CnHm, CO2 or N2O are building up Concentration is increasing

PERU LNG 2009

6

Hydrocarbons Safety „

Proper and Wrong operation of a bath type vaporizer DISTILLATION after pluging of a channel in the vaporiser Pluging by solid : - suspended solids (aerosol of oil - dust of adsorbent) - dissolved impurities CO2, N2O after reaching the solubility limit. Then concentration in liquid impurities (CH4 - C3H8 - C2H6)

PERU LNG 2009

7

Hydrocarbons Safety „

Proper and Wrong operation of a bath type vaporizer Normal Operation: Excess liquid flowing out No concentration

Dry Boiling: No liquid out Concentration build up

Normal level

Low level

Deposit starts if liquid gets saturated and Contaminants cannot be eliminated with the gas phase

Low level

PERU LNG 2009

8

Hydrocarbons Safety „

Application: APSA-L – E02 Vaporizer

CnHm enter

LRV VAPO E02

αIN × QIN

αLRV × QLRV αLR × QLR

LR

PI 4.2 barg

CnHm exit

QAIR QAIR αLR = αAIR ≈ αAIR K × QLRV + QLR QLR Purge PurgeRate Rate==0.2% 0.2%of ofAIR AIRFLOW FLOW Concentration Concentrationfactor factor==500 500

Air Aircontent content CH CH44 == 55ppm ppm CC2HH6 == 0.2 0.2ppm ppm 2 6 CC2HH2 == 0.5 ppm 0.5 ppm 2

2

LOX LOXcontent content CH CH44 == 2500 2500ppm ppm CC2HH6 == 100 ppm 100 ppm 2 6 CC2HH2 == 250 250 ppm ppm 2

2

PERU LNG 2009

9

Hydrocarbons Safety „

Adsorption Principles „

H2O and CO2 free air

The Front End Purification (FEP) is designed to stop completely : D H2O D CO2

„

But other impurities from the air pass through the adsorber before CO2 : D D D D D

CH4 C2H6 C3H8 N2O C2H4

Air with all contaminants

Methane Ethane Propane Nitrous Oxide Ethylene

REACTIVATION ADSORPTIO N

And Andmay mayenter enterinto intothe theCold ColdBox Box PERU LNG 2009

10

Hydrocarbons Safety Adsorption capacity of Front End Purification total Front end purificaton

„

H2O, CO2, nC4H10, C2H2, O3.

partial

none

C3H8, NO

N2O, NO2, C2H4

H2, CO, CH4, C2H6

ADSORPTION LEVELS

PERU LNG 2009

11

Hydrocarbons Safety „

Contaminants dangerous for the purification

Some CONTAMINANTS can badly damage the molecular sieves They are mainly: - the acid gases : CI2, SO2, H2S etc., NH3 - miscellaneous organic molecules

PERU LNG 2009

12

Hydrocarbons Safety „

Potential hazards in the Front End Purification „

Abrasion of a part of the adsorbent (velocity too high) D Risk of channeling = by pass flow D Risk of lower adsorption capacity D Risk of introducing adsorbent dust in the cold box

„ „

Internal bypass of the beds, by leakage Liquid water carry-over (separation problem) : D CO2 adsorption capacity is reduced if water vapor reaches the molecular sieve D A part of the adsorbent can be destroyed

„ „ „

Presence of some aerosols which go through the FEP Presence of dangerous contaminants in the mole sieve Too long adsorption phase : D “break-trough” of CO2 or H2O Example of CO2 entering an APSA L4 : -10 ppb of CO2 entering continuously : 2 kg per year -2 ppm of CO2 during 15 minutes : 15 grams of deposit PERU LNG 2009

13

Hydrocarbons Safety Triangle of FIRE applied to E02 Vaporizer

ER EN

Velocity of gaz / liquid? Ozone decomposition ? Static Electricity ?

GY

CnHm deposits CnHm dissolved Aluminium

FU EL

„

OXYGEN LR Purity Liquid state

PERU LNG 2009

14

Hydrocarbons Safety „

Event sequence to explosion Spontaneous ignition of reactive material on Aluminum platefin main vaporizer in cold box

Combustion of accumulated hydrocarbon contaminants on Aluminum vaporizer cores

Presence of airborne fuel - aerosols light hydrocarbons concentration/accumulation in LOX & on Aluminum surfaces with N2O or CO2 ice & dry-boiling

Explosive rupture of cryogenic distillation column

Flash vaporization of cryogenic liquid

Massive runaway combustion of Aluminum exchangers in oxygen (exothermic reaction)

Uncontrolled escalation to explosion

PERU LNG 2009

15

Hydrocarbons Safety „

Risks related to the impurities in the vaporizers

During the operation of the ASU, the concentration of impurities in the bath of the vaporiser may lead to strong explosions : - Hydrocarbons, such as Ethane, Propane, Ethylene, Acetylene, or aerosols, can concentrate and/or deposit. The Lower Inflamability Limit is reached in LOX - Ozone is a strong ignition agent These explosion hazards exist when there is a lack of LOX (LR) feed into the passages, caused by : - Too low level of the bath of the vaporiser - Plugging of passages by solid deposits: CO2* , N2O*, dust... * Risk of accidental deposit of CO2 or N2O, due to their low solubility in LOX, 5 ppm and 160 ppm respectively.

PERU LNG 2009

16

Hydrocarbons Safety „

Possible Damage Overview

PERU LNG 2009

17

Hydrocarbons Safety „

How to control the CnHm hazards

The 8 GOLDEN RULES D1. Environmental Survey D2. Operation of FEP D3. Operation of Vaporizer D4. Deconcentration purge D5. Periodical Deriming D6. Control of the transient phases D7. Control of other sources of pollution D8. EIS management

PERU LNG 2009

18

Hydrocarbons Safety „

1. Environmental Survey 1. Surrounding industries and distances 2. Atmospheric conditions 3. Air analysis 4. Communication with surrounding industries „ The plant operator shall maintain an environment file including following information : D Nearby industries liable to release gases D Distances between those potentials sources and the air intake of the ASU (+ height of sources) D Presence of haze (organic aerosols)

Polluted site or Not ?

PERU LNG 2009

19

Hydrocarbons Safety „

2. Operation of FEP Complete retention of CO2 in FEP is of vital importance for the unit (low solubility in RL : 5 ppm at –181°C) „ Air conditions evolutions have an impact on : „

D Mass Flow Rate D Pressure D Temperature D Duration of the adsorption D Air Cleanliness „

Regeneration conditions act on : D Regeneration gas flow rate D Duration of heating D Heating temperature

PERU LNG 2009

20

Hydrocarbons Safety „

2. Operation of FEP „

FEP performance control : CO2 content analysis at outlet D 1 ppm D 3 ppm

„

Alarm Shutdown of the unit after 15 minutes

Control of the desorption effectiveness : temperature peak D Alarm in case of “no heat peak”

„

Recommended REGEX operation after CO2 breakthrough test (3 years)

PERU LNG 2009

21

Hydrocarbons Safety 3. Control of the level of bath vaporizer Upper level tap (100%of the transmitter scale) Level sample 100% immersion (Level Set Point) 90% immersion (Low Level Threshold) 80% immersion (Very Low Level Threshold) Height, m

„

70% Lower tap of LT2

LT2

LT1 2nd transmitter = improvement

0% immersion Lower level tap for LT1 (0% of LT1)

Plant Shutdown after 1 hour Transmitters:

• Calibration using the heights and the density of the liquid • Check with level sample gauge

PERU LNG 2009

22

Hydrocarbons Safety „

4. Deconcentration Purge Deconcentration line: 1/2”.LR.04 „ Deconcentration type: intermittent purge (but permanently in service) „ Deconcentration volume: at least 0.2% of the air flow „ Deconcentration control: sequence linked to the level of vaporizer E02 „

D Time of purge is constant D Level drop is monitored D Alarm is raised in case of low level drop

PERU LNG 2009

23

Hydrocarbons Safety „

5. Periodical Deriming „

The objective is to vaporize any contaminants which may have entered in the equipment of the cold box D Every 3 years D Applied to cold box equipment only (compressor and FEP are running independently) D Deriming operation • Low pressure • High flow

D Deriming mean • Dry air • Usually ambient temperature • Exceptionally hot temperature (65°C is the limit for the aluminum heat exchanger)

D Refer to PFD PERU LNG 2009

24

Hydrocarbons Safety „

6. Transient Phases „

Start-up D As much liquid production as possible D Minimum air input D Liquid assist after first liquid production (LIN only)

„

Shut-down D Drain ALL liquid after 48h shut-down D Drain if E02 level is below 80% immersion

„

Change of run-type D Maintain vaporizers level

„

Normal run D Control of frosted pipes and dead-ends

PERU LNG 2009

25

Hydrocarbons Safety „

7. Other sources of pollution „

Machine: Turbine D Lubricated machine D Seal gas pressure

„

Instrument air D Usually: dry air D Back-up ?

„

Air intake D Car parking, Truck unloading D Hot works, fires... D Exchanger water leak...

PERU LNG 2009

26

Hydrocarbons Safety „

8. E.I.S Management „

E.I.S = Element Important for Safety D Safety Protection Loops D Alarm and Shutdowns parameters • Set-points • Delay • Hysteresis

D Qualified personnel „

Management of Change

PERU LNG 2009

27

Hydrocarbons Safety „

Conclusions Hazard Hazardisisaacombination combinationof of AApolluted pollutedatmosphere atmosphere AAnot notproper properoperation operationof ofthe thevaporizer vaporizer

Can Can lead lead to to severe severe accidents accidents THE THEGOLDEN GOLDENRULES RULES 1. 1.Environmental EnvironmentalSurvey Survey 2. 2.Operation Operationof ofFEP FEP 3. 3.Operation Operationof ofVaporizer Vaporizer 4. 4.Deconcentration Deconcentrationpurge purge 5. 5.Periodical PeriodicalDeriming Deriming 6. 6.Control Controlof ofthe thetransient transientphases phases 7. 7.Control Controlof ofother othersources sourcesof ofpollution pollution 8. 8.EIS EISmanagement management PERU LNG 2009

28

DERIMING AND EXCEPTIONAL REGENERATION

PERU LNG 2009

1

1. Deriming Procedure „

Deriming and Drying Procedure „

Purpose DRemove contaminants in every locations they are subject to accumulate DAccelerate to warm up of the plant after a shutdown

„

Main recommendations DAll liquids should be completely purged before starting deriming DStart deriming with all valves closed D6 phases in order to defrost progressively the plant DProceed from a clean circuit towards a dirty circuit DUse the lowest pressure possible DKeep the deriming outlets wide open DControl the deriming flow rate in order to avoid high velocities

PERU LNG 2009

2

1. Deriming Procedure

PERU LNG 2009

3

1. Deriming Procedure

PERU LNG 2009

4

2. Exceptional Regeneration „

Purpose D Remove impurities not desorbed during regular reactivation D Exceptional procedure to avoid any damage

„

Carry out : D At initial start-up • To clean from contaminants accumulated during transportation • To control adsorption capacity respect to design capacity

D After an pollution accident • Late reversal • Liquid water from R02 • Unusual temperature at the inlet of the dryers

D After repetitive CO2 “break-through”

PERU LNG 2009

5

2. Exceptional Regeneration „

Highlights D Passing dry gas at low pressure and increased temperature D Long period of time through the bottle (24 hours at least) D Temperature in the bottles may range from 230 to 290°C D Temperature increase : two steps to avoid damage of adsorbents Temperature

Outlet electrical heater

290°C

Bottle bottom ~ 240°C 145°C ~120°C

Phase 1

Phase 2

Effective Effectivepart partof of exceptional regeneration exceptional regeneration

Phase 3

Phase 4

Time

PERU LNG 2009

6

2. Exceptional Regeneration Q(WN 2) )==121 Q(WN 121Nm3/h Nm3/h 2 PP(V-6701 A) = 1.033 (V-6701 A) = 1.033bar barabs abs TITI513 outlet = 240°C 513 outlet = 240°C

ATM

EH-6701 PV 561 From Exchangers

KV 540

TI 580

Instrument Air Deriming Air To Exchangers

V-6701 A

V-6701 B

ATM

KV 515

TI 513

ATM

AIR C01

Inlet Water Outlet Water PERU LNG 2009

7

PERU LNG NITROGEN GENERATOR SYSTEM TRAINING

PERU LNG 2009

1

NITROGEN GENERATOR TRAINING 1. Process description APSA L 2. Air Purification Unit 2. 1 Exceptional Regeneration 3. Turbine Expanders 4. Cold box – warm standstill 5. Production 6. Trip and shutdown 7. Start up cold standstill 8. Control loop description 9. Stutdown

PERU LNG 2009

2

1. Process description APSA L

Compression

Purification

Heat exchange

Cold production

Distillation

PERU LNG 2009

3

2. Air Purification Unit To start it we should do a “Initialization”; for this the inlet valve should be close and the inlet pressure PT_502 at 0 bar. You choose the bottle which be in regeneration and press initialization button. The Bottles will place in HP isolation step. You open inlet valve FV_580 to pressurize the bottle on line and the HP cold box Open it to have enough flow for regeneration. You should open the KV_540 to send air in regeneration bottle and put the PV_561 in auto mode with SP at 160 mbar. When flow from cold box is enough you close KV_540. When the timer step is done and you have all condition, a indication “Next step” appear you can move manually the sequence by Next step button If you need to move all the sequence you have a Bypass button to bypass the heating and cooling timer. But this don’t bypass other step. If all is correct you should put the sequence in auto mode in order to avoid CO2 breakthrough. You can open air production valve FV561 and put in auto SP 750 AIR Nm3/h In case of problem you must put the sequence in manual mode and check the problem. PERU LNG 2009

4

2. Air Purification Unit 1. High Pressure Isolation Isolation of the bottle in adsorption Timer step 360s

Cold Box N2

2. Depressurization The bottle is slowly depressurized in opposite direction to the adsorption flow. Drop pressure of bottle should be done during step timer else we have “Depressurization to long” and stop the sequence. Timer step 300s

KV_540

cold box

heater

Cold Box N2

KV_540

cold box

heater

KV_530

KV_530

V-6701A

V-6701B

Hp isolation

In service

V-6701A

V-6701B

Hp isolation

In service

venting

venting

KV_515

KV_525

KV_515

KV_525

KV_516

KV_526

KV_516

KV_526

KV_510

KV_520

Air

KV_510

KV_520

Air

PERU LNG 2009

5

2. Air Purification Unit 3.Blow-off Start to send flow thought the bottle. We should have minimum 8 mbar of DP on heater else Alarm ”EH-6701 Heater low flow”. Timer step 60s Cold Box N2

KV_540

cold box

heater

4.Heating The heater starts to increase temperature at around 150°C In case of the outlet temperature is always < 135°c after 15 min Alarm «Heater start fault » Timer step 45mn Cold Box N2

KV_540

cold box

heater

KV_530

KV_530

V-6701A

V-6701B

Blow Off

In service

V-6701A

V-6701B

Heating

In service

venting

venting

KV_515

KV_525

KV_515

KV_525

KV_516

KV_526

KV_516

KV_526

KV_510

KV_520

Air

KV_510

KV_520

Air

PERU LNG 2009

6

2. Air Purification Unit 5. Cooling The heater is turned off and we keep the waste nitrogen Flow to cold down the adsorbent. If the outlet heater temperature is not drop less 50°c in 10min: Alarm « Stop heater fault » Timer step 75min Cold Box N2

KV_540

cold box

heater

6. Low Pressure Isolation Isolation of the bottle regenerate Timer step 120s

Cold Box N2

KV_540

cold box

heater

KV_530

KV_530

V-6701A

V-6701B

Cooling

In service

V-6701A

V-6701B

LP isolation

In service

venting

venting

KV_515

KV_525

KV_515

KV_525

KV_516

KV_526

KV_516

KV_526

KV_510

KV_520

Air

KV_510

KV_520

Air

PERU LNG 2009

7

2. Air Purification Unit 7. Pressurization The bottle is pressurized with purified air from the outlet of the other bottle. If the pressure don’t increase 2 Alarms “Pressurization to long” and “Bottles DP to high” Timer step 1332 s

8. Parallel The purpose of this step is to reduce the temperature of the purified gas entering the exchangers: Timer step 60s

Cold Box N2

Cold Box N2

KV_540

cold box

heater

KV_540

cold box

heater

KV_530

KV_530

V-6701A

V-6701B

Pressurization

In service

V-6701A

V-6701B

Parallel

In service

venting

venting

KV_515

KV_525

KV_515

KV_525

KV_516

KV_526

KV_516

KV_526

KV_510

KV_520

Air

KV_510

KV_520

Air

PERU LNG 2009

8

2. Air Purification Unit Temperature Inlet temperature

Heater temperature

Cold Desorption

Outlet temperature

Hot Desorption heater pick

Blow off temperature

Heating

Cooling

Time

Total Time on line 160 min; Heating Temperature 150°C In case of trip you should note the bottle in regeneration and the bottle on line with the time of both in order to restart on same position. PERU LNG 2009

9

2. 1 Exceptional Regeneration The exceptional regeneration is done only on firth start up and after stop maintenance each 2 years. Or if you make a C02 breakthrough. You should do it in manual mode and activate the Regex button. 290°C

150°C

120°C

PHASE 1

PHASE 2

PHASE 33

PHASE 4 PERU LNG 2009

10

2.1 Exceptional Regeneration Phase 1 The first heating step is equal to a normal regeneration. Start flow to EH-6701 and Temperature at 150°C When outlet temperature reach 120°C start phase 2 Depending of the amount of water adsorbed on the alumina, the duration of phase 1 is expected to be 2h to 4h. „

Phase 2 The temperature should reach 290°C, adjust the regeneration flow to this. When outlet temperature is at 230°C start phase 3. The expected time of this phase is about 2 h to 3h. „

PERU LNG 2009

11

2.1 Exceptional Regeneration Phase 3 Depending on the heat loss, a final temperature of approximately 230°C is reached at the outlet of the vessel for exceptional regeneration. The gas at the outlet of the heater is still at 290°C. Hold the temperature for 6 to 9 hours. „

Phase 4 Turn off the heater (cooling step of the normal sequence) and wait until the temperature at the outlet of the bottle indicates 25°C. The expected time of this step is about 4 h to 6 h „

PERU LNG 2009

12

3. Turbine Expanders RTS No low oil tank level and oil temperature > 24°C Pressure seal gas > 1.5 bar Request Button to start the oil pump Oil pressure > 6,5 HP Column level not high Inlet valve close Nozzle valve close.

PERU LNG 2009

13

4. Start up Cold Box – warm standstill The cold box must be start only after drying, in order to remove totally the water. Some dew point should be done at different point and we should have around - 60°C. The derimming procedure can be use to be sure all lines are dry. - Cooling down: When the compressor running the HP column is pressurized. You start to make flow by opening the FV_565B and put it in Auto mode witch SP at 60% of nominal flow ~2700Nm3/h. You open the HV_502 at 60% to make flow through the E-6702. Open the LV_564 fully to start flow on LP column and send gas to the turbine and put the PV_590 in auto mode with SP at 4 bar.

PERU LNG 2009

14

4. Cold box – warm standstill The oil pump turbine was started and you have the RTS. Open the isolation valve HV_562, the turbine will run at low speed. Open slowly the Nozzle valve by the LIC_552 in manual mode to increase the speed more than 7000 Nm3/h in 2min else you trip. Increase the nozzle opening to close the PV_590 but take care at pressure of LP column and speed of turbine maximum 35 000 rpm Monitoring the outlet temperature TI_558 to don’t reach -180°C This cold will cold the main exchanger E-6701 and decrease the air temperature monitoring on TI552A. Be careful the TI_582 and TI_565 outlet exchanger should be stay warm. The cooling of E-6702 and LP column is monitoring on TI84A and TI556. PERU LNG 2009

15

4. Cold box – warm standstill With the temperature drop the flow will increase Put the FIC_580 in Auto mode to control inlet flow, the SP would be adjusting in order to have a homogeny cooling and not so fast around -1°c by hour to avoid any stress on columns and pipes The first liquid appear in HP column, at around 30% open purge to evacuate it, and after the liquid in LP column. When the liquid are rebuild, close the HV_502 at 50%. Adjust the turbine load and put the LIC_552A in auto mode SP at 45% Put the LV_564 in auto mode SP at 100%

PERU LNG 2009

16

5. Production Gan Production: When the cold box is stable and the purity AIT_568 is < 50 PPM Put FIC_580 in Cascade mode and insert the flow request on HIC565 Activate the Gan Production Button. This will put in auto mode the flow controller FIC_565A with SP the HIC565 and adjust the FIC77B SP at 5% less in order to send gas to customer; If consummation is enough the FV_565B valve will be totally close and in case of flow degrease or stop the valve will adjust the flow out of cold box. In case of purity come > 200 ppm the valve FV_565A will close and when the purity came back the valve will open automatically.

PERU LNG 2009

17

5. Production Lin Production: The Lin production can be activate only if the turbine run, if we have enough liquid in HP column and a good purity. If the pressure PI606/PI626 < 9.8 bar and LI605/LI625 < 90%. This activation will increase the air inlet flow of 6%.

PERU LNG 2009

18

6. Trip To avoid unit trip directly the faults are separated but after some delays if no action are take the unit will trip. -

Dryer sequence stop. I20T D Air to V-6701A delta pressure is too high during pressurisation of V-6701A (PI_502 – PI_512) (UA502A) D Air to V-6701B delta pressure is too high during pressurisation of V-6701B (PI_502 – PI_522) (UA502B) D V-6701A depressurization step is too long (UAn52A) D V-6701A pressurization step is too long (UAn52B) D V-6701B depressurization step is too long (UAn55A) D V-6701B pressurization step is too long (UAn55B) D Electrical heater EH-6701 heating start failure (UAn57A) D Electrical heater EH-6701 heating stop failure (UAn57B) D Heater flow end tempo alarm PDALL_534 (PDALL_534) D Outlet C02 analyse alarm too high (AAHH542)

If this condition appear the cycle is stop and a timer of 15 min start. If the problem is not resolve you activate next trip.

PERU LNG 2009

19

6. Trip Turbine TRIP DEmergency stop (HS584) DOutlet turbine temperature alarm too low (TALL558) DTurbine seal gas too low pressure (PALL570) DTurbine oil too low pressure (PALL572) or (PSLL575B) DTurbine speed alarm low (575Turbine speed alarm too high (SAHH575) or (SSHH575) DTurbine vibration alarm too high (VAHH575) DTurbine oil pumps off (ES_586A&B) DTurbine oil return temperature alarm too high (TAHH571) DUnit Shut Down The trip of the turbine don’t trip the cold box but after some time you will lose the liquid level.

PERU LNG 2009

20

6. Trip „

Cold Box TRIP D D D D D D D D D D D D

Condenser E-6702 level alarm too high (LAHH551) HP column C-6701 level alarm too high (LAHH552) Condenser E-6702 level alarm too low (LALL551) + Gan prod Condenser E-6702 not submerged alarm (LALL564) + Gan prod Emergency button (HSn53) Gaseous Nitrogen temperature alarm too low (TALL565) Waste oxygen temperature alarm too low (TALL582) Condenser E-6702 level alarm low (LAL551) + Gan prod + Turbine off Instrumentation air pressure too low (PAL550) Unit Trip Instrumentation open loop ESD

Close Lin Production and Gan Production FV_565A the valve B will open. Open LP column purge when level come high.

PERU LNG 2009

21

6. Trip „Unit

TRIP

DESD DInlet air pressure too low (PALL502) DAir Purification Shut Down > 15 min DEmergency switch HS n53 DInlet Air temperature alarm too high (TAHH 502) 30sec delay. DWaste Oxygen pressure alarm too high (PAHH 571) 30sec delay. DCold box trip DCnHm purge trip 24hr delay DCnHm alarm too high (AAHH_584) 24hr delay DCold box inlet air temperature alarm too high (TAHH_580) DInstrument air header pressure low ( PALL 550) DOperator stop Reduce N2 Production request at 2250 Nm3/H Trip APU; Cold Box; Turbine Action more: Inlet air valveFV_580at 15%.

PERU LNG 2009

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7. Star up – Cold standstill To start we should not be in level high alarm in Hp column and LP column, purge liquid if you need. Start the oil turbine system When compressor and Apu have started and in auto mode. Put the LV_564 in auto with Sp at 100% in order to keep level in LP column Start flow with the FV_565B SP 2700Nm3/h. When turbine is RTS start it in manual mode, increase speed higher than minimal at this moment the level in the vaporizer will start to increase and decrease according to the pressure fluctuation until the PIC590 stabilizes the pressure. When all is stable put the LIC_552A in auto. Be careful the temperature decrease faster than Warm standstill. Also the flow increase so put the FIC_580 in auto mode. When the purity come back start the production PERU LNG 2009

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8. Control loop description PIC 561 D Waste gas pressure outlet turbine control Functions: 1. ensure that enough residual gas is going through the heater (PV_561 closed) for regeneration of the adsorption bottles 2. maintain the turbine discharge pressure stable „

If the pressure PI561 then the valve PV_561 Action direct This controller must remain in automatic mode Typical set point = 160 mbar NB: forced jump at every bottle change-over (+/- 20%) PX 561

PIC 561

PT 561 COLD BOX

E-6701

Silencer

PV_561

Atm

V-6701AV-6701B

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8. Control loop description PIC 590 D E-6702 Condenser pressure AND D01 inlet pressure Functions: 1. Maintain E-6702 condenser pressure stable in order to keep a column pressure stable 2. AND keep the turbine delta P constant If the pressure PI590 then the valve PV_590 Action direct This controller must remain in automatic mode Typical set point = 4,2 bar „

PIC 590 PT 590

E-6702

PV_590

D01 D01

To V6701A/V6701B PERU LNG 2009

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8. Control loop description „

FIC 565A

D Gaseous nitrogen to customer Function: Limit the nitrogen flow to the network at the requested flow available from the cold box. If the flow FI565 then the valve FV565 Action reverse The set point: SP565A = HIC565 (In Cascade mode) (HIC565 => GAN request by the operator on the DCS) FX 565 PT 565 GAN

C-6701

FT 565

FIC 565A

FY 565A

<

PIC 556 PT 556

TE 565

To GAN Network

E-6701 FV615A

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8. Control loop description „

FIC 565B D Gaseous nitrogen to the vent Function: Maintain a (nearly) constant flow out of the cold box if the flow to the network is lower than the requested flow. If the flow FI565 then the valve FV_565B Action reverse In cascade mode the set point: SP565B = SP565A -5% (Calculated by the PLC) FX 565 PT 565

FT 565

FIC 565B

TE 565 S04t

GAN

C-6701

E-6701

Silencer

ATM

FV_565B

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8. Control loop description „

FIC_580 D Control the air flow at the inlet of the cold box Function: Maintain a constant air flow to the Cold Box If the flow FXI580 then the valve FV_580 Action reverse In cascade mode the set point is calculated according to the nitrogen requirement RSP580 = (A * HIC565) + HIC502BG +- AIC565 (A is the extraction ratio adjusted during start-up) HIC565 GAN request by operator HIC502BG Bias request by operator AIC565 Can be increase or decrease SP value 500 Nm3/h

HIC 565BG BIAS Request

FX 580 V-6701A V-6701B

C01 C01

FIC FIC

SP

FIC FIC

HIC 565 GAN Request

PT 580

FT 580

TE 580

AIC 565

FV_580

+- 500 Nm3/h AIR TO COLD BOX PERU LNG 2009

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8. Control loop description „

LIC_552A

D Column C-6701 Level Function: Keep a sufficient cold production when the plant is running in “Gas mode”. The output of this controller is acting on the turbine nozzles If the level LI552 then the valve HV_573 Action reverse Typical set point = 45 %

D01 D01

C-6701

LIC 552A

LT 552

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8. Control loop description „

LIC_552B D Column C-6701 Level Function: Control the column level while the plant is running in « liquid production mode ». The output of this controller is acting on the LV552B If the level LI552 then the valve LV552B Action direct Typical set point = 45 % (same as LIC_552A)

LV552B

LIN STORAGE

C-6701 LT 552

LIC 552B

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8. Control loop description „

LIC564 D Condenser E-6702 Level Function: Maintain always the E-6702 condenser level above the top of the condenser by liquid transfer from C-6701 to E-6702. If the level LI564 then the valve LV_564 Action reverse The set point = 100 % immersion. For safety reason (to avoid dry vaporization and then hydrocarbon concentration), it must be respected. Automatic mode. LIC 564

E-6702

LT 564

LV_564

C-6701 PERU LNG 2009

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8. Control loop description „

SIC575 D Turbine speed controller Function: Maintain the speed to the nominal value by acting on the Inlet Guide Vanes (IGV’s) If the speed SI575 then the IGV’s HV_573 Action reverse This controller is generally not used because the IGV’s are normally controlled by LIC_552A HV_573

D01 D01

ST 575

SIC 575

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8. Control loop description „

Oil Brake valve D Turbine oil flow adjustment Function: This is not a controller, it just allows you to act manually on the oil brake and by this mean, adjust the frigorific capabilities of the turbine. It is adjusted manually to change between LIN and GAN runs If the valve is , the speed and the power Action reverse This valve must never be totally closed in order to avoid any over speed or any damage in the cartridge by over heating of the oil. The oil temperature should never exceed 100°C

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9. Shutdown Shutdown Before stop the plant to be sure Nitrogen backup work properly and the air instrumentation backup is available. To shut Down the plant you can put the Operator stop button this is equal at unit trip or unload each part and stop it. The check valve CVW011 will close to avoid liquid purge go back to waste line. It is better to stop Air Purification Unit after a complete regeneration of bottles in order to restart on this. If the plant is stop less than 48 hours we can keep the liquid inside monitoring by hydrocarbon analyzer. To be sure valve PV_590 and PVn89 are in auto mode and the HV_502 is fully open to control pressure. If it is more than 2 days the liquids must be drain to avoid concentration of hydrocarbon and if it is for maintenance the plant should be warm up. PERU LNG 2009

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