- Количество слайдов: 21
Progress and Challenges in the Field of Applied Energy - Addressing the Challenges Annual ACERC Review Meeting February 20, 2003 Salt Lake City, UT
US Energy Flow Diagram - 2001 Combustion fraction of total energy (85%) Source: Energy Information Administration, Annual Energy Review 2001
Challenges for Combustion • Pollutants (NOx, SOx, PMxx) • NOx (SCR performance, biomass) • PMxx (soot from vehicles, pool fires) • Hg Speciation • Sustainable/green-house-gas-neutral Energy • Biomass (reactivity, NOx, deposition, corrosion, fly ash utilization) • Black Liquor (reactivity, aerosols, gasification) • Operations • Corrosion, Ash Utilization, Black Liquor Gasification • Modeling (pulverized coal, fixed bed, fluid bed)
Particulate Matter Projects • Characterization of Source PM – NSF/CONACy. T • Source apportionment Factor Loadings Factor Scores
PM Projects • Characterization of PM – Military Vehicles - SERDP
Soot • C-SAFE – Center for the Simulation of Accidental Fires and Explosions
Soot deposition – Eddings, Sarofim P A R Agglomeration T I C Growth L Particle E Oxidation 50 ms 10 ms inception Growth in MW PAH formation 1 ms Precursors M O L E C U L A R Modeling by Sarofim, Lighty – Aerosol dynamic eqs. Growth dynamics Oxidation kinetics Experimental work by Eddings, Sarofim, Lighty, Pugmire Modeling by Violi, Voth, Sarofim
Mercury Control • 1470 tons emitted by coal-fired Power Plants (1995) • 105 metric tons by North American Power Plants
CO 2 -Neutral/ Renewable Sources
Cofiring Best Uses Resource
Field Unit Design • Slip-stream sample with continuous, unmanned NOx and NH 3 monitoring. • Chambers for testing six catalysts simultaneously. • Established agreements with four catalyst vendors (Hitachi, Siemens, Haldor-Topsoe, and Chormetec) supplying five catalyts. • Designed for six-month deployment.
3 -D Particle Recreation
Required Aerating Agent
Large Difference in Deposit Behavior
Alternative/Renewable Sources • Black Liquor Gasification/DOE • Investigation of bed properties • Investigation of fuel conversion/gas production TI PI • Modeling of conversion • CFD modeling of FB PIC TI TI Cyclones PI Pressure control valve FI PI TI Freeboard Gas to analysis TI Nat. Gas BL tank (heated) Afterburner TI Bed heater s. TI FI Circ. pump Water Cond FIC Compressed air TI TI Separato r TIC Super heater Boiler TI CW TI PI Metering Bed pump material FIC Air Eductor FI Product gas to eductor Flue gas to facility's flue gas handling system, SO 2 scrubber Condensate
Summary • Combustion dominates energy production world wide. • Energy use and economies correlate strongly in developed countries. • Combustion processes create environmental challenges, especially air quality. These include NOx, SOx, PM 10, PM 2. 5, CO, O 3, CO 2, Hg, acid rain • Improved combustion engineering has directly led to about a 25% decrease in criteria pollutant concentrations over the last 30 years even as GDP has increased 160% and population has increased 40%. • Future challenges (global warming, toxic metals, and sustainable supplies) are more formidable than past issues.
Conclusion • Engineers well trained in combustion sciences are and continue to be in very high demand. • Most formidable combustion challenges require technical solutions, the development of which are likely to come from engineering disciplines.
Vapor deposition flux [g/m 2/h]