Che 397 - Team Bravo

“Garbage to Gas”

Team BravoEleftherios Avtzis

David GarciaBryan Isles

Zack LabaschinAlena Nguyen

Mentor Dan Rusinak

Municipal Solid Waste

• EPA 2008 report on MSW generation– Approximately 250 million tons of MSW

generated by Americans in 2008• ~33.2% is recycled and composited (83 million tons)

– Approximately 4.5 pounds of MSW generated per person per day• 1.5 pounds of the 4.5 is recycled and composited.

Che 397 - Team Bravo

Che 397 - Team Bravo

Municipal Solid Waste

Che 397 - Team Bravo

Why MSW?

• Renewable Energy Source• Helps the Environment (CH4 emissions)

• Cost effective• Transportation Reduction• Located near cities and existing

infrastructure

Che 397 - Team Bravo

Disadvantages of MSW

• Preparation of feedstock• A lower heating value than conventional

feedstocks • Higher Ash content than conventional

feedstocks

Design Basis

•Commercial Scale Production• 2500 metric tonnes per day MSW • 1800 metric tonnes per day Syngas

•Landfill choice• Location• Proximity to City• Water Sources• Size and expansion

Design Basis

• River Bend Prairie Landfill– 88 Acres– 20 Acres of expansion– Access to MSW of

Chicago– Rail and River access– Residential– Limited Expansion

Design Basis

• Newton County Landfill– 265 Acres– Room for expansion– Access to MSW of South

Chicago– Transportation– No river access

Design Basis

• Environmental ReviewPositives• Removal of MSW from local landfill (75% of 2500 metric

tonnes per day low end value enter gasification processing)• Gasification by-products are captured and properly stored

(no venting into atmospheres)– Negatives• 400 million lbs of hazardous waste per year (mostly ash)• 100,000 lbs will need relocation (cannot be further utilized)

Design Basis

Industrial Standard Review• Clean Syngas produced in 2.05 ratio H2/CO for use by

chemical production

Clear Statement of Feedstock• MSW from landfills• Return to landfill includes: glass, appliances, paints or

oils• Metal will be recycled

Che 397 - Team Bravo

Block Flow Diagram

MSW to RDF

• MSW – municipal solid waste in• Sorting – removal of recycle metals and

other rejects• Screening procedures• Shredding and drying • RDF – Refuse Derived Fuel out

Gasification Reactions

• C is a carbon containing compound

• Char reacts with CO2 and steam (gasifier)

C + H2O CO + H2 + 131 MJ/kmol

C + CO2 CO + 172 MJ/kmol

• Combustion reactor heats sand (olivine)C + ½ O2 CO - 111 MJ/kmol

CO + ½ O2 CO2 - 238 MJ/kmol

H2 + ½ O2 H2O - 242 MJ/kmol Che 397 - Team Bravo

Che 397 - Team Bravo

Water-Gas Shift and Methane Rxns

CO + H2O CO2 + H2 - 41 MJ/kmol

• Slightly exothermic• Required to achieve Syn Gas ratio of 2.05• Great opportunity for methane reforming

• CH4 + H2O CO + 3H2 + 206 MJ/kmol

Che 397 - Team Bravo

Composition of Syn Gas

Compound PercentH2 45 – 48%

CO 15 – 20%

CH4 10 – 13%

C2H4 1 – 3%

CO2 18 –20%

C2H6 0 – 1%

N2 Trace

TBE Gasification Process

Disadvantages of Other Processes

• High pressure/Energy intensive• Lower quality raw syngas• Air or oxygen requirements• Poor scale up• Unproven technology

Advantages of TBE Process

• Low pressure• Relatively low temperature• Efficient ash removal• Indirect gasification• Residence time less than one second

References

• Municipal Solid Waste (MSW) to Liquid Fuels Synthesis, Volume 1: Availability of Feedstock and Technology (PNNL-18144)

• Municipal Solid Waste (MSW) to Liquid Fuels Synthesis, Volume 2: A Techno-economic Evaluation of the Production of Mixed Alcohols (PNNL-18482)

• www.taylorbiomassenergy.com - TBE • www.rentechinc.com - Rentech• Municipal Solid waste Generation, Recycling, and Disposal in the United

States: Facts and Figures for 2008 – EPA• Higman, Christopher and van der Burgt, Maarten. Gasification 2nd Edition.

Gulf Professional Publishing. Oxford, 2008.• Paisley, Mark A., Corley, Ralph N. and Dayton, David C. Advanced Biomass

Gasification for the Economical Production of Biopower, Fuels, and Hydrogen. Taylor Biomass Energy