2010 WTERT

WTERT research on resource recovery from wastes by gasification

Marco J. Castaldi Department of Earth & Environmental EngineeringHenry Krumb School of Mines, Columbia University

WTERT 2010 Bi-Annual Meeting at Columbia UniversityNEW YORK CITY, OCTOBER 7 & 8, 2010

2010 WTERT

Summary (from WTERT 2004)• Developing Novel Technologies for Improved MSW Applications

Efficiency GainsEmission ReductionsDynamic Control

• Drawing on ExpertiseChemical Mechanism DevelopmentHigh Temperature KineticsCatalytic Reactor Design

• PostersCatalytic Rubber Gasification (Kwon)Waste Plastic Gasification to Useful Chemicals (Llewelyn)Greenhouse Gas Reforming (Castaldi)Corrosion Phenomena in WTE Facilities (Albina)Size and Shape Analysis of Particles in WTE Facilities (Nakamora)Breaking Down Municipal Solid Waste for Combustion (Whitworth)

2010 WTERT

Gasification Combustion• Sub stoichiometric air• Lower total volumetric flow• Lower fly ash carry over• Pollutants in reduced form (H2S,

COS)• Char – Low T• Slag – vitrification – high T

• Excess air• Higher volumetric flowrate• Fly ash carry over• Pollutants in oxidized form (SOx,

NOx, etc)• Bottom ash

2010 WTERT

CO & H2 --------- CO2 & H2O

Transitioning from chemical rearrangement to heat generation, thus Carnot cycle comes into play

Thermodynamic Efficiency Analysis

Source: M. J. Prins et al. / Chemical Engineering Science 58 (2003) 1003 – 1011

2010 WTERT

Enhanced Char Burnout: CO2

Douglas Fir: 0% CO2

• Identical time on stream, reaction

temperature profile, total flow rate

• Physical evidence of more efficient

gasification with CO2

Observed for 100’s samples tested

Douglas Fir: 30% CO2

Walnut Shells: 0% CO2 Walnut Shells: 30% CO2

~20% biomass

remaining<2% remaining as

inorganic ash

2010 WTERT

CO2 impact on gasification products

Fi 1 H d i i h CO ifi i

Reactor Temperature (oC)

600 700 800 900 1000

H2 M

ole

Frac

tion

(10-1

)

0.000

0.005

0.010

0.015

0.020

0% 5%10%15%20%40%50%

CO2 Variation

Increasing CO2

Increasing CO2

CO increases with CO2 H2 decreases with CO2

2010 WTERT

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

5.5

0% 10% 20% 30% 40% 50%

% CO2 added to gasification influent

H2/C

O p

rodu

ced

in g

asifi

er

H2/CO (Syngas) Tuning• Fuels • Chemicals• Combustion• Fuel cells

Fisher Tropsch – diesel fuels

Gas Turbine Combustion – Low NOx operation/good stability

Fisher Tropsch – Fe & Co-basedCatalyst processes

specialty chemicals

SOFC operation

2010 WTERT

20.7 16.66

15.6020.03

N

N

CH3

CH3

1

2

3

4

5

6

7

Peak Identification

Fuel Synthesis from Waste Streams

2010 WTERT

Combustion Gasification

Model

Model

Experiment & Simulation Comparison

2010 WTERT

Experiment & Simulation “Scale Up”

O2/Coal=0.6

O2/Coal=0.9O2/Coal=0.9CO2 Recycle

O2/Coal=0.6CO2 Recycle

TGA (~20 mg)

Drop tube (~ 2 g/min)

Image Source: Tondu Corporation, Houston, Texas 77079Plant Simulation (ASPEN ®)

2010 WTERT

Evaluation of Field Systems

• Technical and Economic AnalysisMS Thesis – Caroline Ducharme “Technical and economic analysis of

Plasma-assisted Waste-to-Energy processes”

• Mass and energy balances were developed for each process– Company data & engineering estimates

– Economic analysis comparison to grate combustion systems

• Plasma Technologies– InEnTec– Europlasma– Alter NRG– Plasco

2010 WTERT

INENTEC Plasma Unit

Integration:• Gasifier• Plasma Unit• Thermal Residence Unit

All operated in “sweet spot”

2010 WTERT

WasteManagement & InEnTec

2010 WTERT

EuroplasmaSystem:• Stoker Grate Gasifier• Plasma Unit for Syngas Cleaning• Plasma Unit for Ash Vitrification• Commercial Startup April 2011.• Plant capacity will be 50,000 tons/y• Net electrical output 12 MW

2010 WTERT

Alter NRG (Westinghouse)System:• Metallurgical coke (met coke) injected

• retain the heat energy from the plasma torches• Provide a “skeleton” to support MSW in the

gasifier• Similar to the phenomena occurring in an iron

cupola or blast furnace. • Process can handle any moisture in MSW • Main commercial plant in Utashinai

• Originally; 80% ASR / 20% MSW @ 180 tpd• Plant operating on 100% MSW @ 150 tpd

2010 WTERT

PlascoSystem:• Demonstration plant in Ottawa built in 2008• Two stages process:

• Horizontal Traditional gasification @ 700°C• Syngas Production: plasma torches @ 1200°C.

• Electricity production• syngas GT combustion• Waste heat for combined cycle.

2010 WTERT

Plasma Field System SummaryTechnology Energy (kWh/ton) Capital Costs ($/ton)

InEnTec 530 ~77 (est)

Alter NRG 617 81

Europlasma 605 86

Plasco 530 86

Grate WTE (US avg) 550 60

2010 WTERT

Landfill Gas Utilization

More reactive system; Reduce/eliminate secondary fuel usage

BurnerIC Engine

Gas Turbine

Heat, CO2,Steam, Energy

LFG

Air

H2,CO

Bleed LFG

catalyticreactor

Bleed Air

Flow Splitter/mixer

Secondary fuel

Kohn, M., et al.” App. Catal. B: Environ, (94), 2010, 125-133.Barrai, F.; et al. Catalysis Today 2007, 129, (3-4), 391-396.

2010 WTERT

LFG Catalytic Reaction Regions

CO2

CH4

H2

CO

O2H2O

Monolith Outlet Temperature

0

100

200

300

400

500

600

700

800

0%

2%

4%

6%

8%

10%

12%

14%

16%

0 0.5 1 1.5 2 2.5 3 3.5 4

Tem

pera

ture

(deg

C)

Mol

ar F

ract

ion

Time (hours)

1 2 3 4

CombustionCH4 + 2O2 CO2 + 2H2O

Steam ReformingCH4 + H2O 3H2 + CO

Dry ReformingCH4 + CO2 2H2 + 2CO

rWater Gas ShiftCO2 + H2 CO + H2O

2010 WTERT

Test Apparatus @ CCL

200 kWe Design Concept2 kWe Laboratory test engine

Catalytic reactor

2010 WTERT

0

50

100

150

200

250

300

0% 10% 20% 30% 40% 50%

CO2 fraction

NO

X [p

pm]

0.2kW0.4kW0.6kW0.8kW0.2 kW simulation0.4 kW simulation0.6 kW simulation0.8 simulation

0

20

40

60

80

100

120

140

160

180

200

0% 5% 10% 15%

syngas fraction

NO

X [p

pm]

0.2kW0.4kW0.6kW0.8kW0.2kW simulation0.4 kW simulation0.6 kW simulation0.8 kW simulation

CO2 reduction of N radical concentration N + CO2 NCO + O

Reduce prompt mechanism by reacting with fuel radicalsCHx + CO2 CHO + CO

CO2 also serves as diluent – reduces concentrationsRCHN = kCCHN CCHN is reducedRN2O = kCN2 CO

LFG and Syngas impact on NOX

2010 WTERT

Test data from Honda Engine on LFG

Test data shows lower emissions possible across all loads utilizing syngas produced from LFG

•SLFG = simulated landfill gas

•10% syngas added = SLFG mixed with 10% syngas

2010 WTERT

Looking over the horizon• Next generation combustors – higher energy density

– Low NOx operation– Approach 3+ MW m-2

• Liquefaction of wastes (T ~ 300 – 500 ºC)– Removal of O2

• In-situ reduction of corrosive gases– Injection of halogen scavengers

• Novel uses of ash – catalytic and property adjustment

• LFGTE Applications and LFG to fuels– Casella Energy to implement in DE

2010 WTERT

Acknowledgments• Collaborators

– Tuncel Yegulalp, Columbia Univ.

– Robert Farrauto, BASF Catalysts, LLC.

• Students– Alex Frank (WTE Modeling – Poster)

– Natali Ganfer (LFGTE Engine Testing – Poster)

– Naomi Klinghoffer (Beneficial Use of Ash - Poster)

– McKenzie Primerano (LFGTE Catalyst Testing – Poster)

– Garrett Fitzgerald (Hydrates – Poster)

– Caroline Ducharme (Plasma Gasification)

– Amanda Simson

– Federico Barrai

– Kelly Westby (ugrad)

• Visiting Scholars – Jin Yuqi, Zhejiang University

– John Dooher, Adelphi University

– Zhixiao Zhang, Hangzhou University

• Post-Docs – Eilhann Kwon

– Heidi Butterman

You, the audience for listening

Please visit CCLlabs.org

2010 WTERTM. J. Prins et al. / Chemical Engineering Science 58 (2003) 1003 – 1011

C (s) + gas

Gas only – no C(s)

• Most HC fuels (CxHyOzNaSb) exist above lines

• Need oxygen source or hydrogen to get below

(CO2, O2, air H2O, H2)

2010 WTERT

Total energy constant

Once all carbon is converted, more air does not help

Rearrangement (chemical Exergy)

Heating (physical Exergy)

Begin combustion reactions regime

2010 WTERT

Combustion & Catalysis Lab (CCL)H2

CO/H2 – engine application

electricity

CO2

To market or community. Stock: plastic furniture household etc

C2H2

plastics or raw materials

Alternative CH4/CO2source – Landfill gas

CH4Hydrates

CO2 CH4

CO2

H2OElec.

H2 + CO2

Air

FuelReforming

Fuel Cell

CO2 capture &GHG reforming

Biomas andWaste to Energy (WTE)

Other fuelsFuelCell

“The nature of environmental issues is changing from a regulatory to a resource focus” R. MacLean, Env. Protec. April 2003, P.12

Resources for energy production will continue to be in demand

2010 WTERT

Stiochiometry & Equilibrium

Ref: STANJAN calculations

C + O2 CO2 + 2H2ODeep Ox 2H2 + COC + O2

Partial Ox

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

CH4/Air

Com

posi

tion

0

500

1000

1500

2000

2500

Tem

pera

ture

( o C

)

H2

H2O CO

CO2

Temperature

C / Air