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Coal : Fuel of the Past or Fuel for the Future
Tomasz S. WiltowskiAdvanced Coal and Energy Research Center and
Department of Mechanical Engineering and Energy Processes
Southern Illinois UniversityCarbondale, IL 62901
Clean Coal Technologies
Grand Challenges for Next 50 Yearsfrom Nobel Laureate Richard Smalley (1943-2005)
1. ENERGY2. WATER3. FOOD4. ENVIRONMENT 5. POVERTY6. TERRORISM & WAR7. DISEASE8. EDUCATION9. DEMOCRACY10. POPULATION 2004 6.5 Billion People
2050 ~ 10 Billion People
Crowdedthe United States population on May 15, 2015 was: 315,857,050the World population on May 15, 2015 was 7,085,613, 221
http://www.census.gov/main/www/popclock.html
Mumbai, India - Rush Hour
China = 1.37BIndia = 1.17BAmerica = 0.94BAfrica = 0.92BEurope = 0.82BThe Rest = 1.56B
US growth rate 18 births every 4 minutes World growth rate 615 births every 4 minutes
Our Interest - Sustainable Development
• “development that meets the needs of the present generation without undermining the capacity of future generations to meet their needs.”
Coal’s Sustainability Challenge
• Economic and social criteria make a compelling case for coal – the issue is environmental performance
• Climate change concerns present a complex challenge for the continuing use of fossil fuels and coal in particular
Clean Coal Technologies:
-Gasification-Oxycombustion-Chemical Looping-Coal to Liquids-CO2
Integrated Gasification Combined Cycle (IGCC)
Gasification is essentially partial oxidation under pressure
IGCC + Carbon Capture and Storage
IGCC + CCS + Poly generation
Barriers to IGCC Commercial Deployment
• Cost → 10-20% penalty for bituminous coal• Traditional PC can meet current environmental standards• IGCC financing costs higher than PC – perceived risk profile• No reward for risk taking – new plants largely being built
by regulated utilities• Excess capacity in many regions - NGCC overbuild• IGCC needs more project development than NGCC or PC
– To date no standard IGCC design - this will change with GE entry
• Lack of familiarity with IGCC in the power industry (it is a chemical plant)
“NOVEL” COAL COMBUSTION
Combustion Efficiency and
Pollutants Emission Improving efficiency levels increases the amount of energy that can be extracted from a single unit of coal. Increases in the efficiency of electricity generation are essential in tackling climate change.
Background In most conventional combustion processes, air is used as the
source of oxygen; Nitrogen is not necessary for combustion and causes problems
by reacting with oxygen at combustion temperature; A high concentration of nitrogen in the flue gas can make CO2
capture unattractive; With the current push for CO2 sequestration to ease climate
change, it is imperative to develop cost-effective processes that enable CO2 capture;
The use of pure oxygen in the combustion process instead of air eliminates the presence of nitrogen in the flue gas, but combustion with pure oxygen results in very high temperatures
Oxycombustion
Coal
Oxycombustion
Chemical Looping Combustion (CLC)
Chemical looping combustion (CLC) has emerged as one of the most promising technologies for low-cost CO2 capture technologies for solid fuels. CLC provides the possibility of CO2 capture without the requirement of an air separation unit or an absorption process.
What is Chemical LoopingBasic concept
What is Chemical Looping and does it work?
Limestone based Chemical Looping Process
Chemical Looping features:
up to 100% CO2 capture efficiency,
highly concentrated stream of CO2 ready for sequestration,
no NOx emissions,
no costs or energy penalties for gas separation,
CLC uses well-established boiler technology, which
means that costs can be assessed with great accuracy, and
higher efficiency is because chemical looping systems use solids to carry the oxygen in and out of the process, leaving essentially no thermodynamic penalty associated with either the carbon separation or oxygen production.
Efficiency of Chemical Looping
CRITICAL PROBLEM WITH SOLID FUEL:
Can the fuel particles and oxygen carrier particles be readily separated? If not, there is carryover of solid fuel to the oxidation reactor and emission of CO2 in the air regenerating the carrier particles.
Hence, solids require a modified strategy
FISHER – TROPSCH Synthesis Of Liquid
Fuels
Synfuels: 1-2 barrels of oil per ton of coal
Coal To Transportation Liquids (CTL)
Coal Gasification Fischer-Tropsch
What are the challenges that must be overcome before coal to liquids
becomes a reality? 1. Uncertainty regarding crude oil prices-oil at $70,
make a bundle: oil at $40 lose your shirt.2. Reducing the cost of conversion process: some
uncertainty remains.3. Climate change: coal releases more CO2 than
other fuels. CO2 injection? CO2 conversion?4. Usage in engines-who will certify fuels?
CO2 emissions vs fuel type
NREL technical report NREL/TP-840-400665
lbs
per
MW
hCoal
Natural gas564
331
CO2 Chemical Utilization
CO2
High-addedValue materials
Organic carbonates& carboxylates
organics
Renewable fuels & chemicals
CH4. CH4, CH3OH, HCOOHhn
H2O
ChemicalsLight olefins
ODH
SynfuelsCH3OH
CH3OCH3
HCOOHH2
SyngasH2/CO
RWGS
SynfuelsHydrocarbons
&alcohols
FT Dry Reforming
THANK YOU!