Pilot Plant Testing of Piperazine (PZ) with Advanced Flash Regeneration

Gary T. Rochelle (PI) & Eric ChenThe University of Texas at Austin

Katherine Dombrowski (PM), AECOM

Andrew Sexton (TE), Trimeric

Bruce Lani, DOE PM1

86 psia/5.7 bar254 F/123 C

307 F/153 C

240 F/116 C

302 F/150 C

152 F/67 C

Rich25 gpmLdg=0.4

LeanLdg=0.22

Cold BypassExchanger

Condenser

StripperSteamHeater

Hot CrossExchanger

CO2

Cold RichBypass2 gpm

Warm RichBypass9 gpm

242 F/117 C

100 psia Steam319 F/159 C

Advanced Flash Stripper with 5 m PZ for NCCC

2

Outline

• Funding and objectives : NCCC summer 2017• Equipment for NCCC: small stripper • Capital and Energy << MEA• Solvent Management of PZ - prepared

3

Project Budget ($million)

4

Cost share by CO2 Capture Pilot Plant Project (C2P3)

BP1 BP2 TotalFederal 1.6 3.0 4.7Cost Share 1.1 0.3 1.3Total 2.7 3.3 6.0

Objective is to develop PZ with advanced regeneration at 150°C

• Optimize solvent (8m vs 5m)• Demonstrate resistance to

oxidation, nitrosation, & corrosionPZ

• Two stage flash (2SF)• Advanced flash stripper (AFS)Regeneration

• Formation and control• CharacterizationAerosols

5

Phased testing at UT SRP and NCCC to optimize PZ absorption/regeneration

• 2SF• 8m PZ

SRP 2011

• 1SF• 5m PZ• Aerosol

SRP 2013

• AFS• 5 vs 8m• Aerosol

SRP 2015

• AFS• 5m PZ• Aerosol

NCCC 2017

6

Completed Completed Completed Construction in progress

0.1 MW 0.5 MWCO2 in air Flue gas

BP1 BP2

Our test window: Jun-Aug 2017

7

2015 2016 2017Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Activity Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9

Skid Process Design

Package for HAZOP

Skid Procurement

Skid Fabrication

Skid Installation

Water Test

Commissioning

Start-Up

Field Campaign

Site Restoration

Analysis/Reporting

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74 ft18 inch

40 ft Packing

107 ft26 inch

60 ft packing

33 ft10/20 inch

13 ft packing

Contactors (to scale)NCCC AFS

Default 5 m PZ

40 ftpacking

Absorber Absorber StripperStripper

AFS Heat Exchangers

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Application Q (kBt/uhr)

Side(inches2)

Volume(ft3)

Type

Stm heater 650 32x32 17 Compabloc

Hot Cross 644 85x61 104 P&F

Cold Rich 143 25x51 17 P&f

Condenser 28 22x36 10 P&F

Cold Cross(existing)

102 x 78 147 P&F

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TEA per Rev2a, Case 12

Capital Cost < MEA w Simple Stripper

AFS < Simple stripper• Total exchanger duty of AFS ≤ Simple stripper• Total no. of exchangers of AFS ≈ Simple stripper

– Size limited so multiple exchangers are needed– Arrange in series rather than parallel

5 m PZ < 7 m MEA• Absorber for PZ<MEA (2 x faster absorption)• Stripper for PZ<MEA (2-3 x greater P & <Qreb)• Compressor for PZ<MEA (2-3 x greater P)

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AFS reduced energy requirement by 25%

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Advanced amine scrubbing gives 50% eff;Limited by capital-energy tradeoff

0

15

30

45

Weq

(kJ/

mol

CO2)

DOE Case 10MEA/SS

(120°C, Pstrp=1.6 bar)

SRP 2015PZ/AFS

(150°C, Pstrp=6 bar)

Wmin,comp

Wmin,sep

Wlost,absorber

Wlost,cross X

Wlost,reboiler

Wlost,comp

Wlost,others

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Advanced Flash Stripper with other solvents

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Solvent kg’(10-7mol/Pa-s-m2)

Weq(kJ/mol CO2)

Simple stripper AFS

7m MEA 4.3 36.3 32.7

10m DGA 3.6 37.0 34.2

8m PZ 8.5 34.9 31.4

5m PZ 11.3 36.5 32.3

2m PZ/3m HMPD 10.1 34.9 31.0

• 𝑅𝑅𝑅𝑅𝑅𝑅𝑅 𝑃𝑃𝐶𝐶𝐶𝐶2∗ = 5 𝑘𝑘𝑃𝑃𝑘𝑘, 𝐿𝐿𝐿𝐿𝑘𝑘𝐿𝐿 𝑃𝑃𝐶𝐶𝐶𝐶2

∗ = 0.2 𝑘𝑘𝑃𝑃𝑘𝑘

• Optimum cross exchanger ∆𝑇𝑇𝐿𝐿𝐿𝐿 = 5𝐾𝐾 𝜇𝜇𝜇𝜇𝑀𝑀𝑀𝑀𝑀𝑀

0.175

PZ losses and environmental impact• Resistant to corrosion, use more carbon steel• Moderate volatility

– Manage losses w water wash– Manage impurities with thermal reclaiming

• Resistant to Degradation– Thermally stable to 150°C– Oxidation, 4x less than MEA– Nitrosation, decompose at 150oC

• Manage aerosol w grow and capture• Manage solid precipitation w rich storage 15

Laboratory Corrosion Apparatus

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Corrosion at stripper T, no O2

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0

500

1000

1500

2000

2500

100 110 120 130 140 150 160

Cor

rosi

on R

ate

(µm

/yr)

T (°C)

4 m HTOR PZ, 1010 CS

3 m Tarong PZ316 L SS

3 m Tarong PZ, 1010 CS

8 m SRP PZ, 316 L SS

8 m SRP PZ, 1010 CS

D.O. Consumption and Metals Cycling in HTOR

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0

0.2

0.4

0.6

0.8

1

1.2

1.4

0 0.1 0.2 0.3 0.4 0.5

NH

3(m

mol

/kg/

hr) (

FTIR

)

Fe2+ (mmol/kg) (ICP-OES)

0.23 mol NH3/(cycle-mol Fe2+)+ 0.05 mmol NH3/(kg-cycle) due to D.O.

(~50% D.O. consumption per cycle)

+90 mM Inh A

+100 mM Inh A

D.O. Stripping

D.O. Stripping

NH3 rate with D.O. stripping or Inh A

NH3 rate

0.8-1 mole NH3/mole PZ oxidized

Oxidation Mitigation

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• Reaction w D.O.: 0.05 mmol/kg/cycle in HTOR• Minimize holdup at high temperature before stripper

• Metals cycling: +0.23 mmol/(kg-cycle-mmol/kg Fe2+)• Fe2+ solubilized by accumulation of degradation products

• Oxidation Fe2+ accumulation more oxidation• NO2MNPZ Oxidation in pilots w/ coal flue gas• Prescrub NO2 and reclaim solvent to minimize Fe2+

PZ can be used w/o solid precipitationOn shutdown, drain to rich storage

0

10

20

30

40

50

0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45

Tran

sitio

n T

(°C)

CO2 loading (mol/mol alkalinity)

5 m PZ 8 m PZ

Solution

PZ∙6H2O (s)

Operating RangeOverstrip Saturation

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0.22 0.26

0

2

4

6

8

10

12

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Dia

met

er (u

m)

Z/Ztot

Water Wash10 ft RSP250

Intercooling

Absorber2X10 ft RSP 250

Manage PZ aerosol by Grow and captureCalculated Aerosol Growth for SRP run 1

5 m PZ, L/G=3.6, 83% removal

Conclusions

• The Advanced Flash stripper will reduce Weq by 10-20% for PZ and other solvents

• 5 m PZ is a superior solvent• Fast absorption, thermally stable, high P stripper• Good resistance to corrosion, oxidation • Manage aerosol and solids

• 5 m PZ with the AFS will reduce capital cost

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• Acknowledgement: “This material is based on work supported in part by the Department of Energy under Award Number DE-FE0005654.”

• Disclaimer: “This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.” 23

Amine Aerosols can be measured by FTIR and

Phase Doppler Interferometer (PDI)

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