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Solvent Selection and Solvent Selection and Recycling for Carbon Recycling for Carbon Absorption in a Pulverized Absorption in a Pulverized Coal Power PlantCoal Power Plant

Richard ReedKansas State University

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Outline of PresentationOutline of PresentationLiterature Review

Overview of Fossil Fuel Power plantsOverview of Carbon Dioxide

AbsorptionAspen FlowsheetResults from Simulations

The need for OptimizationSimulated AnnealingAcknowledgements

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OVERVIEW OF FOSSIL OVERVIEW OF FOSSIL FUEL POWER PLANTSFUEL POWER PLANTS

Research and Development Solutions, LLC (RDS), comp. Bituminous Coal and Natural Gas to Electricity Final Report. Tech. no. DOE/NETL-2007/1281. 1st ed. Vol. 1. Print. Cost and Performance Baseline for Fossil Energy Plants.

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NGCC produces the cleanest NGCC produces the cleanest emissions followed by IGCCemissions followed by IGCC

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NGCC plants are the most NGCC plants are the most efficient followed by IGCCefficient followed by IGCC

PC Power plants are selected PC Power plants are selected for the projectfor the projectPC power plants have poor

efficiencies and high emissions comparatively

50% of the worlds power is produced by PC power plants

Interested in retrofitting current power plants to improve sustainability

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OVERVIEW OF OVERVIEW OF CARBON DIOXIDE CARBON DIOXIDE ABSORPTIONABSORPTIONMetz, Bert. "Chapter 3 Capture of CO2." IPCC Special Report on Carbon Dioxide Capture and Storage. Cambridge: Cambridge UP, 2005. Print.

Post Combustion is ideal for retrofitting current power plantsPre-Combustion

◦Difficult to introduce because of components

Post Combustion◦Fits into the end of the process

Oxyfuel◦Burns fuel in pure oxygen producing

high temperatures

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Post Combustion removes Post Combustion removes carbon after the combustion carbon after the combustion of fossil fuelsof fossil fuels

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ASPEN FLOWSHEETASPEN FLOWSHEET

The conceptual design is The conceptual design is much simpler than the Aspen much simpler than the Aspen flowchartflowchart

The Components of the PC The Components of the PC power plant are split into three power plant are split into three partsparts

S E P

R Y I E L D

M I X E RR S T O I C

M I X E R

M I X E RR S T O I C

W

MIXER

F S P L I TM I X E R

P U M P

H E A T E RH E A T E R

W

M I X E R

W

F S P L I T

Q

M I X E R

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M I X E R

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M I X E R

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M I X E R

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M I X E R

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M I X E R

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M I X E R

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M I X E R

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M I X E R

S E P M I X E R

M I X E RS E P

W ar n i ng s

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The flue gas is separated The flue gas is separated into 2 streams before into 2 streams before passing through the passing through the absorbersabsorbers

S E P

R Y I E L D

M I X E RR S T O I C

M I X E R

M I X E RR S T O I C

W

MIXER

F S P L I TM I X E R

P U M P

H E A T E RH E A T E R

W

M I X E R

W

F S P L I T

Q

M I X E R

Q

M I X E R

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M I X E R

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M I X E R

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M I X E R

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M I X E R

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M I X E R

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M I X E R

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M I X E R

S E P M I X E R

M I X E RS E P

W ar n i ng s

Absorber

Strippers

CO2

Recycle

Absorber

Strippers

Recycle

CO2

CO2

CO2

Fresh Solvent Inlet

Fresh Solvent Inlet

Clean Flue Gas

Clean Flue Gas

CO2 RichFlue Gas

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CHEMICAL OR CHEMICAL OR REACTIVE REACTIVE ABSORPTIONABSORPTIONKenig, Eugeny, and Panos Seferlis. "Modeling

Reactive Absorption." CEP January (2009): 65-73. Print.

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Equilibrium based absorption Equilibrium based absorption assumes that each stage in assumes that each stage in the process is in equilibriumthe process is in equilibrium

Works well for very fast reactions

Less accurate for real absorption processes◦Equilibrium is seldom reached

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Rate-Based models include Rate-Based models include the actual rates of the mass the actual rates of the mass and energy transfer as well and energy transfer as well as the reactionsas the reactionsMuch more accurateLeads to large, complex modelsHigher computational time

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RESULTS FROM RESULTS FROM SIMULATIONSSIMULATIONSThe Need for Optimization

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Reflux Ratio:1MEA: 0.3 by mass fractionFlow plate at tray 2

Effect of Number of Trays on Carbon Effect of Number of Trays on Carbon Absorption and Power RequirementAbsorption and Power Requirement

Incorporates design specification of a 95% absorption of CO2

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Number of Trays: 20MEA: 0.3 by mass fractionFlow plate at tray 2

Effect of Reflux Ratio on Carbon Effect of Reflux Ratio on Carbon Absorption and Power RequirementAbsorption and Power Requirement

Incorporates design specification of a 95% absorption of CO2

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Number of Trays: 20Reflux Ratio: 1Flow plate at tray 2

Effect of Fraction MEA on Carbon Effect of Fraction MEA on Carbon Absorption and Power RequirementAbsorption and Power Requirement

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Number of Trays: 20Reflux Ratio: 1MEA: 0.3 by mass fraction

Effect of Feed Location on carbon Effect of Feed Location on carbon absorption and power requirementabsorption and power requirement

Incorporates design specification of a 95% absorption of CO2

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SIMULATED SIMULATED ANNEALINGANNEALINGDiwekar, Urmila M. "Discrete Optimization." Introduction to Applied Optimization. Norwell, Mass.: Kluwer Academic, 2003. Print.

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Simulated annealing is a optimization Simulated annealing is a optimization algorithm which can escape from local algorithm which can escape from local min/maxmin/max

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Simulated annealing is a Simulated annealing is a optimization algorithm which can optimization algorithm which can escape from local min/maxescape from local min/max

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Work in ProgressWork in Progress

Utilizing Simulated Annealing to optimize the absorption section in the PC power plant

Incorporation of a second solvent, DEA◦Mix the solvents MEA and DEA with

varying concentrations

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AcknowledgementsAcknowledgementsFunding provided by The National

Science Foundation and Department of Defense, EEC-NSF Grant # 0755115

Research Opportunity provided by the University of Illinois at Chicago (UIC)

Guidance provided by Drs. Diwekar, Jursich, Kotecha, Takoudis and Salazar

Are there any Questions?Are there any Questions?