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Coal Mining. Open Pit Mine. Underground Mine. Coal Conversion Processes. Carbonization and Pyrolysis Low severity (mild gasification) High temperature Direct Liquefaction One-stage reactor technology Two-stage reactor technology Co-processing Hybrid Indirect Liquefaction Gas reactors
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Coal Mining Open Pit Mine Underground Mine
Coal Conversion Processes • Carbonization and Pyrolysis • Low severity (mild gasification) • High temperature • Direct Liquefaction • One-stage reactor technology • Two-stage reactor technology • Co-processing • Hybrid • Indirect Liquefaction • Gas reactors • Slurry reactors
Why Coal-To-Liquids (CTL)? • Energy Security • Size of coal resources • Distribution of resources • Environment • Utilization of clean coal technology • Sequestration technology expected • Flexibility • Advanced technology • Co-production capability • Economics • Competitive with alternatives • World oil price volatility
Coal-to-Liquids – Part of an Unconventional Fuels Portfolio • Growing consensus on need to diversify transportation fuel sector • Long term: hydrogen • Intermediate term: liquids from coal, oil shale, liquids from biomass, increased domestic petroleum production, efficiency • Advantages of Coal and CTL Technology • U.S. coal reserves amount to 250-year supply at current rates of consumption • Coal resources are dispersed (proven reserves in 26 states) • 1 ton of coal can be processed into 2 barrels of high-quality liquid fuels • Offers opportunity to pre-invest in eventual hydrogen-from-coal production facility
Coal Liquefaction HTU Direct Coal Liquefaction Process H2S, NH3, COx Recycle H2 C1 – C2 Gas Recovery Treatment Make-Up H2 LPG Gasoline Refining Coal + Catalyst Diesel Fuel H-Donor Slurry Fractionation Slurry HVGO Solvent De-ashing DAO Ash Reject
Hybrid DCL/ICL Plant Concept Indirect Coal Liquefaction (F-T) Raw ICL Products Coal Gasification F-T Tail Gas Product Blending and Refining Final Products H2 Hydrogen Recovery H2 Direct Coal Liquefaction Coal Raw DCL Products
Shenhua DCL Process Light Gases Recycle Solvent Catalyst Gasoline Coal Prep Coal Slurry Mixing Jet Fuel Liquefaction Fractionation Separation Upgrading Diesel Residue N2 H2 Purification Gasification Air Air Separation O2 First Train: 1 MT/a Liquefaction Oil
Indirect Coal Liquefaction Overview • Synthesis Gas • Production • Gasification • Reforming • Steam • POX • ATR Natural Gas Coal Pet Coke Biomass Wastes F-T Liquid Synthesis Slurry/Fixed/ Fluid-Bed Tail Gas Power Generation Product Recovery Hydrogen Recovery H2 Liquid Fuels Wax O2 Oxygen Plant Air Wax Hydrocracking Product Storage Naphtha/ Diesel Liquids
Barriers to Coal-To-Liquids • Technical • Integrated operations of advanced CTL technologies have never been demonstrated • Economic • Uncertainties about future world oil production • High capital and operations costs • Investment risks • Energy price volatility
Barriers to Coal-To-Liquids • Environmental • CO2 and criteria pollutant emissions • Expansion of coal production and requisite infrastructure (railroads, railcars, etc.) • Water use • Commercial Deployment • Competition for critical process equipment, engineering, and skilled labor • Who would take the lead in commercial deployment? Part power part liquid fuels • Social • NIMBY and public resistance to coal use
Gasification Technology Overview:The Basic Chemistry A partial oxidation process that can convert any hydrocarbon into hydrogen and carbon monoxide (synthesis gas or syngas). (CH)n + O2 H2 + CO For example: 2 CH4 + O2 4H2 + 2 CO [ Methane] [Oxygen] [Hydrogen] [Carbon Monoxide] Process Conditions: 1,800 – 2,800 Deg F, 400 – 1,000 psig
Clean Coal Generation Technologies • Pulverized Coal • Fluid Bed Combustion • Integrated Coal Gasification Combined Cycle
IGCC Overview Energy Ventures Analysis Inc
Integrated Gasification Combined Cycle • Air vs. oxygen blown gasifiers– potential to save Air separation unit costs, reduce onsite power consumption • Dry vs. slurry fuel feed– Improve energy efficiency by 2.6% • Hot syngas clean-up– Improve energy efficiency 1.0-1.5% • Improve gasifier reliability to save redundancy • Gas turbine advancements– new turbine classes (FB->H 2.2% improvement), hydrogen rich fuel combustion for carbon regulation world • Shift reactor technology to maximize syngas CO2 capture and hydrogen production for carbon regulation • Syngas mercury capture
Activated Carbon Injection with COHPAC to Reduce Mercury Selective Catalytic Reduction To Reduce NOx Emissions Flue-Gas Desulfurization to Reduce Sulfur Dioxide Emissions MEA Scrubber to capture Carbon Dioxide Emissions
Basic Idea of a Power Plant Steam Spinning turbine blades and generator Boiling water
Four Stages of Coal Combustion • Primary Devolatilization • Coal Tar + Light HC + H2O • Secondary Pyrolysis • Tar Light HC + soot • Homogeneous Oxidation • Light HC + O2CO2 + H2O • Char Burnout • C + O2CO2
Potentiality of coal gasification technology • CO2 issue is increasingly getting hot topics, requirement of High Efficiency Technology such as IGCC or IGFC, will be increased in future. • It is necessary to proceed CCT program included outlook of CO2 recovery and sequestration as a final target. • In this case, Coal Gasification will be Key Technology considering of coal utilization potentiality in future. • Coal Gasification is also possible to apply for NH3, GTL, and H2 production, it can be said that the technology expandability is so wide range.
AC GT ST HRSG Potentiality of coal gasification technology Gas Clean Up Electricity IGCC, IGFC Coal Gasifier Synthetic Fuel GTL, DME Synthetic Chemical Fuel Reactor Oxygen Synthetic Chemical Fertilizer Reactor Air Separation Unit Fertilizer Hydrogen Sift Reactor CO2 CO2 Disposal CO2 Separator Under the Sea Underground Coal Mine