Evaluation of emissions of substances other than CO2 from … · 2013. 7. 25. · NGCC Natural Gas...

Evaluation of emissions of substances other than CO2 from power plants with

Post Combustion CaptureEva Sanchez Fernandez, Toon van Harmelen, Arjan van Horsen,

Magdalena Jozwicka, Earl Goetheer, Mohammad Abu-Zahra

TNO Gas TreatmentDelft, the Netherlands

IEAGHG

TNO Gas Treatment Group17/05/20111

Content

Impact of PCC on emissions. Importance and challenges.

Methodology: two ways approach Harmonization and Modelling

Model construction

Cases: USC and NGCC

Sensitivity analysis

Conclusions and future work


Evaluation of emissions. Importance & challenges

Uncertainties in the impact of CCS to the environment

Scarcity in environmental data in relation to CCS

Standardization and reliability in the existing data

Broader study: among the technologies analyzed the focus here is on Post

Combustion Capture (PCC)

Goal:

Development of systematic and clear methodology for waste and emissions

evaluation

Quantify the effects of PCC technology on emissions of other substances

than CO2


Two way approach for evaluation of emissions

Harmonization: statistical analysis of

the emissions database created by

reviewing the open literature.

Corrections are applied to bring into

line all cases in the database

Modelling: Commercial software

package (Aspen Plus®) used to

evaluate plant performance and

basic emissions. Emission factors

used for trace components.

Two different methods are used and compared

HARMONIZATION MODELLING

Emissions Database Reference cases

Step 1: Process Simulation ToolsPower and capture plant design

Step 2: Source specific emission factorsEvaluation of trace components

Evaluation of emissions for the given cases

Correction FactorsFuel use and sulphur content

Harmonized emission factors

Evaluation of emissions for the given cases

Comparison and analysis

PROJECT ACTIVITIES


Evaluation framework (1)Case 1A 1B 4A 4B

Type USC USC NGCC NGCC

Steam Cycle bar(a)/ºC/ºC

290 / 600 / 620

290 / 600 / 620

124/561/234

124 /561/ 234

Gas turbine NA NAAdvanced F class

Advanced F class

Boiler typeSupercritical PC

Supercritical PC NA NA

NOx ControlsLow NOx Burners & OFA & SCR Low NOx Burners & SCR

PM Controls ESP ESP

H2S controls NA NA NA NA

SOx /Sulphur control

FGD (Wet Scrubber, Limestone) NA NA

CO2separation NA MEA NA MEA

Fuel Type Australian Bituminous coal Gas

Case 1A: USC PC without PCC

Case 1B: USC PC with PCC

Case 4A: NGCC without PCC

Case 4B: NGCC with PCCUSC ultra supercritical

NGCC Natural Gas Combined Cycle

OFA: Overfire Air

SCR: Selective Catalytic Reduction

EBTF. European Benchmarking Task Force. Common framework definition document and Test cases 2010IEAGHG Criteria for technical and economic assessment of plants with low CO2 emissions. Technical review: 2009/TR3


Evaluation framework (2)

Technical criteriaUnits Technical

criteria

Range found in emissions database

Coal type[-]

Bituminous Eastern Australia

Different coal types

Sulphur content in coal%wt

dry 0.95 0.95 – 1.5

CO2 Capture Removal [%] 90% 80% - 100%

CO2 product conditions

Temperature ºC <30 25 - 30

Pressure bar 110 80 - > 156

Standard MEA capture process was used as reference for capture

Emissions generated from solvent degradation are excluded from this study


Harmonization: Treatment of the database

2. HARMONIZATION1. LITERATURE REVIEW Reference cases

Technical criteria

Correction factors

Fuel use

Capture efficiency

Coal sulphur content

3. EVALUATION OF EMISSIONS

Emissions database Harmonized Emissions database

Open literatureRelative emissions factors

Data Sources (37)

Existing operating power plants

Case studies, peer reviewed journals

Data base (176 cases)

Harmonization: Application of correction factors that bring into line the basis

of each case


Harmonization procedure

Corrections were applied to:

Fuel use: Corrected for capture

efficiency and CO2

compression pressure

Capture efficiency for CO2

emissions

Sulfur content in the coal for

SOx emissions


Modelling: Process simulation and emission factors

Process Input Power Plant

(Boiler island , steam turbine island and emission controls)

CO2 capture and compression

STEP 1 – Process modelling Tools and Engineering calculations

CO2 Depleted flue gasCO2. N2, O2, H2O

Energy required for solvent regenerationCooling Water consumptionElectricity consumption (ID fan and pumps)

Flue gas after FGD basic components:CO2N2O2H2O

Bottom ash / Fly ashUnburned coalEffluent Gypsum

Steam OutputElectricity outputCooling water and process water

Fuel flow and compositionAir flowAmmoniaLimestone

Liquid wasteHeat stable salts

NaSO4

Solid wasteActivated carbon impurities

Calculation of solvent loss due to:Oxidation Polymerisation Reaction with acid gases

Trace metals in coal:As, Hg, Se, Be, Pb, etc

Caustic consumption in reclaimerActivated carbon requirement

Solvent make-up

SO2, SO3NO, NO2PM, PM-10Trace metals in Flue gas outAs, Hg, Se, Be, Pb, etc

SO2, SO3NO, NO2PM , PM-10Trace metals in Flue gas As, Hg, Se, Be, Pb, etc

STEP 2 – Estimation of emission factors based on the given technology

TechnicalDescription

Waste inventory

Flue gas outCO2N2O2H2OSO2, SO3NO, NO2PM, PM-10Trace metals: As, Hg, Se, Be, Pb, etc

Liquid wasteHeat stable salts: NaSO4, Na3PO4Effluent

Solid wasteActivated carbon impuritiesBottom ash / Fly ashUnburned coalGypsum

CO2 ProductCO2H2OSO2NOx


Interaction of flue gas impurities with solvent

1. Fix specific degradation rate due to oxidation

2. Concentration of salts in the inlet stream: 1% wt.

3. Fraction of the lean stream reclaimed : fixed to match the HSS formation rate

4. Bottoms: slurry containing 40%wt water

5. Concentration of free amine in the system: 60 mol MEA / mol HSS

6. Concentration of free amine at the bottoms: 0.6 -1 mol MEA/mol HSS

1.Degradation 0.23 – 0.73 kg/tonCO2 @5%O2

6.MPR Services Inc.


USC PC case

Unit 100Coal handling

Unit 200Boiler Island

FGD and Handling plant

Steam turbine Island

ESPRemoval

Particulate matter

Unit 400DeNOx plant

Air

Effluent

Gypsum

Limestone

Process water

Flying ash

Coal

Cooling water out

Cooling water system

Cooling water sypply

Ammonia

Bottom Ash

Flue Gas1

2

8

16

7

1718

5

6

16 17

9

10

20

12

11Emission factors & removal efficiencies applied for these units as a block

Emission factors & removal efficiencies applied for this unit15

19

Sea water

Sea water

1314

CO2 removal Compression

Flue Gas

Reclaimer waste 11

CO2 stream

Emission factors & removal efficiencies applied for these units as a block

Condensate steam return

CO2 reboiler Steam extraction

Condensate

Condensate return

Stream numbers inline with the reference study [5]


NGCC case

Gas Turbine(Equipped with

LNB)

Heat Recovery Steam Generator

Steam Turbine

Process water

Gas

Cooling water system

Waste water

Cooling water supply

2a

CO2 Removal

CO2 Compression

&Drying

Waste water-1

CO2

Flue gas to stack

1

4

8

13

6

12

16

18

16

15 Reclaimer waste

39

10 11

14

Air5

G

Cooling water make up

17

Waste water-219

7

Solvent Make-up20

Caustic21

SCR(possible but not

required)

2b




Output from Harmonization

The Harmonization model was implemented in excel. Results include:

Fuel usage

Average emissions (CO2, SOx, NOx, PM-10, Ammonia) and standard deviation

Different capture technologies (focus on PCC)

0 2 4 6 8 10 12 14 16

Pre (R:17,H:17)

no-capture (R:12,H:12)

Oxyfuel (R:2,H:2)

Post (R:17,H:13)


Oxyfuel (R:12,H:11)

Post (R:16,H:15)


IGC

CN

GC

CP

C

Fuel use (MJ/kWh)

Reference case Harmonised Raw

0 200 400 600 800 1000

Pre (R:17,H:2)


Oxyfuel (R:2,H:1)

Post (R:10,H:2)


Oxyfuel (R:11,H:3)

Post (R:15,H:1)


IGC

CN

GC

CP

C

CO2 emission factor (g/kWh)

Raw Harmonised

0.00 0.20 0.40 0.60 0.80 1.00 1.20

Pre (R:11,H:11)



Oxyfuel (R:12,H:11)

Post (R:10,H:7)


IGC

CN

GC

CP

C

SOx emissionfactor (g/kWh)

Raw Harmonised


Overall waste assesment


Parameter Units 1A 1B 4A 4B

Coal or Gas Flow rate (air dry) t/h 239.8 266.3 56.1 56.1

Fuel LHV kJ/kg 25870 25870 46502 46502

Gross Electricity Out put (D) MWe 831 827 430.3 430.3

Power plant Auxiliaries (E) MWe 73.3 78.3 7.7 7.7

Capture plant additional consumption (F) MWe 83.1 66

Net Electric Output (C=D-E-F) MWe 757.7 665.6 422.6 356.6

Net electrical efficiency (C/A*100) % [LHV] 44.0 34.8 58.3 49.2

Specific fuel consumption MWt / MWe 2.07 2.88 1.71 2.03

Specific CO2 emissions kg/MWh 743 117 354 41.9

Cooling water consumption t/MWh 138.6 240.5 45.6 82.7

Basic Performance of Power plants

Cases 1A and 1B USC PC without and with PCC

Cases 4A and 4B NGCC cases without and with PCC


Main gaseous emissions

Basic components Units

Modelling

Database

Modelling

Database

Harmonization Harmonization

1A 1B 1A 1B 4A 4B 4A 4B

CO2 kg/MWhnet 739 93 735 97 354 42 366 43

SO2 kg/MWhnet 0.26 6.5E-04 0.30 0 1,0E-02 5,9E-05

NOx kg/MWhnet 0.08 0.104 0.36 0.50 0,03 0,03 0.12 0.13

Acid gases

CO kg/MWhnet 0.07 0.09 NA NA 0,09 0,10

HCl kg/MWhnet 0.009 5.4E-04 NA NA

HF kg/MWhnet 0.001 6.8E-05 NA NA

Particulates

PM-10 kg/MWhnet 0.01 0.006 0.04 0.062 9,7E-05 5,7E-05

Ammonia kg/MWhnet 0.107 0.004 0.08 0,04

NOx emissions estimated from the modelling study are much lower than the estimates from the harmonization study

PM shows a different trend between modelling and harmonization

SOx emissions estimated from the modelling study and harmonization study are in good agreement


Main gaseous emissions. Analysis

NOx emissions

0

10

20

30

40

50

60

70

80

90

100

NOx NO2 NO

Em

issi

on

s [m

g/N

m3 ]

Case 1A USC wo capture 85% NOx removal

Case 1A USC wo capture 95% NOx removal

Case 1B USC w capture 85% NOx removal

Case 1B USC w capture 95% NOx removal

Relative NOx emissions

0,00

0,05

0,10

0,15

0,20

0,25

0,30

0,35

NOx NO2 NO

Em

issi

on

s [k

g/M

Wh

net

]

Case 1A USC wo capture

Case 1B USC w capture

LNB & OFA & SCR combination available but not widely demonstrated

Removal efficiency vary in operation from 85% to 95%

Emission target for the present project was 100 mg/Nm3

These controls are capable to reduce the levels to 13ppmv


Trace components in gaseous emissions

Trace metals Units 1A 1B

Arsenic kg/MWhnet 5.20E-05 5.20E-05

Cadmium kg/MWhnet 1.70E-06 1.70E-06

Chromium kg/MWhnet 4.00E-07 4.00E-07

Cobalt kg/MWhnet 1.20E-07 1.20E-07

Lead kg/MWhnet 5.20E-06 5.20E-06

Manganese kg/MWhnet 4.00E-07 4.00E-07

Nickel kg/MWhnet 6.40E-05 8.10E-05

Selenium kg/MWhnet 5.30E-04 6.70E-04

Zn kg/MWhnet 1.50E-02 1.90E-02

Copper kg/MWhnet 1.10E-04 1.40E-04

Total mercury kg/MWhnet 5.70E-06 5.30E-06

Hg0 kg/MWhnet 4.20E-06 4.90E-06

Hg2+ kg/MWhnet 1.50E-06 4.50E-07

Hgp kg/MWhnet 4.00E-08 2.60E-08

Classification of metals1:

Class 1: Little particle enrichment

(manganese, beryllium, cobalt, and

chromium).

Class 2: Enriched in fly ash relative

to bottom ash (arsenic, cadmium,

lead, and antimony)

Class 3: Emitted in the gas phase

(primarily mercury and, in some

cases, selenium).

1 AP-42 ((accesed 2009)). "Compilation of Air Pollutant Emision factors." Us Environmental protection Agency1 Korre, A., Z. Nie, et al. (2010). "Life cycle modelling of fossil fuel power generation with post-combustion CO2 capture." International Journal of Greenhouse Gas Control 4(2): 289-300.


Generated waste. Liquid and solid emissions

Generated waste Units 1A 1B 4A 4B

Particules in ESP kg/MWhnet 19 24 NA NA

Gypsum kg/MWhnet 15 21 NA NA

Furnace bottom ash kg/MWhnet 9.6 12 NA NA

Fly ash kg/MWhnet 29.0 37 NA NA

Mill rejects kg/MWhnet 0.7 0.8 NA NA

Reclaimer waste kg/MWhnet NA 3.291 NA 1.17

Activated carbon kg/MWhnet NA 0.063 NA 0.025

Raw Materials

Cooling water consumption t/MWh 138.6 240.5 45.6 82.7

Specific water consumption t/MWh 0.104 0.410 1.01 1.21

MEA make up kg/tonCO2 1.765 1.79

Activated carbon make up kg/tonCO2 0.075 0.075


Sensitivity analysis. MEA degradation at higher oxygen concentrations

MEA degradation. Case 4B

0,000

0,002

0,004

0,006

0,008

0,010

0,012

0% 5% 10% 15%

Oxygen concentration [%vol]

Was

te [m

3/to

n CO

2]

Reclaimer waste

MEA degradation. Case 4B

0

1

2

3

4

5

6

7

8

0% 5% 10% 15%

Oxygen concentration [%vol]

MEA

deg

rada

tion

[kg/

ton

CO2]

Oxidative degradation

Total MEA loss

( ) [ ] [ ] [ ] [ ]( )78.22

42.32

33.02

91.1/453000 OSOCOMEAekr RT

MEA +⋅⋅⋅=− −

Degradation rate studies from Uyanga, I.J., Idem, O Industrial & Engineering Chemistry Research 46: 2558-2566.


Sensitivity analysis. Waste generation at higher sulphur content

CASE 1B Generated flows with an desulphurisation efficiency of 95% & 98%

CASE 1B Emissions of SOx for different desulphurisation efficiencies

Relative SOx emissions

0.0E+00

5.0E-04

1.0E-03

1.5E-03

2.0E-03

2.5E-03

3.0E-03

0.40 0.60 0.80 1.00 1.20 1.40 1.60

Sulphur content (%wt dry)

SO

x [k

g/M

Wh

]

0.00

0.10

0.20

0.30

0.40

0.50

0.60

0.70

0.80

SO

x [m

g/N

m3]

FGD efficiency at 95%

FGD efficiency at 98%

Generated waste

0.0

1.0

2.0

3.0

4.0

5.0

6.0

7.0

0.4 0.6 0.8 1.0 1.2 1.4 1.6

Sulphur content [%wt]

Was

te f

low

s [k

g/s

]

1.5

1.7

1.9

2.1

2.3

2.5

2.7

2.9

3.1

ME

A lo

ss [

kg/t

on

CO

2]

Gypsum FGD 98%

Gypsum FGD 95%

MEA loss FGD 98%

MEA loss FGD 95%


Conclusions and future workOverall waste assessment of PCC applied to two different power plants has

been performed by different methods:

Harmonization : useful tool for estimating relative emissions in those cases

were technology is well established and much information regarding

emissions is reported.

Modelling: possibility to cover the uncertainties on the emissions of novel

technology.

Uncertainties on degradation rates, rates of HSS formation need to be further

investigated.

USC PC has higher emissions of pollutants than NGCC. However, the higher

oxygen concentration in the NGCC case might lead to more generated waste

in the reclaimer.

Possibilities of waste reduction need to be further investigated


Extra slides (1)

Composition of CO2 stream (Case 1B)

CO2 >99.9%

SO2 34ppmw

SO3 <21ppmw

NO2 <7ppmw

HCl <2ppmw

Hg2+ <2ppbw

Assumption is that 75% of the sulphur capture in the CO2 unit is

recovered as HSS

Evaluation of emissions of substances other than CO2 from … · 2013. 7. 25. · NGCC Natural Gas...

Documents

Transcript of Evaluation of emissions of substances other than CO2 from … · 2013. 7. 25. · NGCC Natural Gas...