Dr. Alexander Alekseev, Linde Group, Technology and Innovation, Linde Fellow

TPM

Oxygen Production for OxyfuelPower Plants

2

Content

• Introduction• Requirements on air separation system for oxyfuel

• Air composition• Thermodynamics: Rectification, how it works• Rectification: Double column system• The whole air separation process• Hardware components

3

HistoryCryogenic Air Separation

1905: 1st cryogenic air separation system build by Carl Linde (a process similar to today´s „chemical looping“ before 1905)

BUTalready in 1726:Jonathan Swift „Gulliver´s Travels“:

„He had two large rooms full of wonderful curiosities, and fiftymen at work. Some were condensing AIR into a dry tangiblesubstance, by exstracting of NITRE, and letting the aqueousor fluid particles percolate…“

4SS 14 Grundlagen der Kälteerzeugung und industrielle Tieftemperaturanlagen 4

Cryogenic Air Separation

1. Air inlet2. Purification3. Compression4. Cooling5. Separation6. Argon recovery

Green – nitrogenBlue- oxygenGray - argon

5

A2626 A/B

C1761 T3212

P3568 A/B

D3432

2

P4568

P4565

T4111

E4118

E4119

T4112

E4116

E3228

X3471

G

X3472

G

X3473G

E3117

E3124

2

C1261

E5117

T5111

P2467

E2416E2417

P2466C1161

S1146

H2O H2O AIR

E2617

COND

STE

AM

D3234

T6111

E6116

Crude KrXe

T3211

E6124

LAR

3

3

Atm

.

Cus

t. A

ir

MP

GA

N1

MP

GA

N2

Sea

l

LPG

AN

HP

GO

XP

GO

XIC

-GA

R LOXto/from tankA

tm. LIN

to/from tank Cru

deN

e/H

e

Atm

.

E3616

E3316

to EVC

Atm

.

Rot

ary

Equi

pmen

t

Hea

t Exc

hang

ers

Dou

ble

Col

umn Rare Gases

Precooling

MS-

Ads

orbe

rsState of the art“ air separation system

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EXAMINA

How much process air is required to produce60 000 nm3/h of oxygen ?

Correct Answer: approx. 300 000 nm3/h

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Requirements on ASU,Products

PRODUCTS OXYFUEL IGCC SCALEOXYGEN

purity 95 --> 97,5% 95 --> 97,5% or 99,5% > 99,5flow, nm3/h > 85 000 > 65 000 30 000 …75 000flow, tpd > 3 000 > 2 500 500 … 2500pressure, bar 1,2 … (20) 40 … 50 < 40 bar

LIQUIDS considerable amountof LIN & LOX

ARGON max argon recovery

NITROGEN no any or small amountfor service purposes

considerable amount or even all nitrogen

produced is pressurized and used as product

nitrogen products amounts

to ca. 20% of the total air flow

for back-up purposes only

no any argon required for process

Conventional

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Requirements on oxygen purity for oxyfuelfrom perspective of an industrial gas company

Ambient presssure oxy-combustion

Elevated Pressure oxy-combustion2010 – 2012: 96-97.5

Before 2005: 99.5%

2005-2006: 95%

2006-2014: 96-97.5%

After 2014: ? (no projects)

2010-2012: 96-97.5%

After 2012: 99.5 ???

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Requirements on ASU,DESIGN/PROCESS

Oxyfuel IGCC Standard

Compressors Single compressor 3-4 compressors 1-2 compressors

Static Equipment Giant heat exchanger, columns, adsorbers

etc

Large scale Medium – large scale

Process Low pressure cycle(main air compressorpressure ca. 5 bar)

Elevated pressurecycles ( main air

compressor pressure> 10 bar)

Conventional cycles,internal compression(main air compressorpressures 5.8-18 bar)

References Schwarze Pumpe Vresova, Pearl QatarJamnagar

A lot

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ASU range, overview, 2010-2015

0

20

40

60

80

100

0 30000 60000 90000 120000 150000

OXY

GEN

PR

OD

UC

T PR

ESSU

RE,

bar

OXYGEN PRODUCT FLOW, nm3/h OXYFUEL IGCC

packaged

CONVENTIONAL

OXYFUEL

CUSTOMIZED

- order- proposal

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ASU process cycles for Oxyfuel Power Plants

0

20

40

60

80

100

Double Column Triple Column Process Triple Column Process(Heat Integration gain)

Pow

er co

nsum

ptio

n, %

ASU Process Cycles for Oxyfuel Power Plant

1212

Power consumption reduced by > 25% !!

Oxygen Purity > 99.5%

conventional process schemesfor traditional applications

Oxygen Purity 95%

Specific Power Consumption0.35 kWh/Nm³

Specific Power Consumption0.25 kWh/Nm³

Above Figures are related to 100% Oxygen (contained Oxygen), normal ambient conditions for design: 20°C, 15°C CW, 60% rel. humidity, at sea level

advanced process schemesfor new applications e.g. IGCC, Oxyfuel

Air Separation UnitsCryogenic Oxygen / Specific Energy Consumption

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Typical Oxyfuel-ASU,PFD

3001.12

GOX LOX

1102

3002.16

3001.11

3001.16

LIN

E3216 - FFE3217 - FFE3218 - Bath

3001.133001.27

3001.26

P356

8

P30

21.6

8

3002.18

Cust. Air

P3566

3001.28

3001.14

2

2

PGAN

3401.71

G

3

3

3002.17

1

Precooling

Purification

Filter

AIR

Thank you for yourattention

TPM