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Illinois Basin Coal Issues. AEP BRO Forum 2013 7/30/2013 By Pat Malone. Illinois Basin. 8000 to 9000 BTU/lb 0.5 to 1.1 lb SO2/mmBTU low fusion ash Rail Transportation to the East. 11,000 to 12,200 BTU/lb 1.8 to 5.5 lb SO2/mmBTU low fusion ash 0 to 0.5% Chlorine.
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Illinois Basin Coal Issues AEP BRO Forum 2013 7/30/2013 By Pat Malone
Illinois Basin • 8000 to 9000 BTU/lb • 0.5 to 1.1 lb SO2/mmBTU • low fusion ash • Rail Transportation to the East • 11,000 to 12,200 BTU/lb • 1.8 to 5.5 lb SO2/mmBTU • low fusion ash • 0 to 0.5% Chlorine Northern Appalachian • 12,000 to 13,000 BTU/lb • 4 to 7 lb SO2/mmBTU • low fusion ash • Rail and Barge access CO/UT Uinta Basin Central Appalachian Powder River Basin • 11,000 to 12,300 BTU/lb • 0.8 to 1.5 lb SO2/mmBTU • high fusion ash • Limited Rail • 11,800 to 12,400 BTU/lb • 0.8 to 2 lb SO2/mmBTU • medium to high fusion ash Texas Lignite • 6.000 to 7,000 BTU/lb • 2 to 3.5 lb SO2/mmBTU • low fusion ash • Mine Mouth Plants Where is the ILB Region
Why ILB? • Proximity to AEP facilities, reduces shipping costs • The ILB is accessible from the Ohio River, and the Mississippi • Aspects of ILB fuels make it a cheaper fuel. • Chlorine Content • Sulfur Content • Low Fusion Ash • ILB as a low cost alternative to NAPP Fuel.
Concerns with ILB • Chlorine Content: • Fouling-high temperature bonded deposits that occur in the reheat and superheater regions of the convection pass that are not exposed to radiation. • Fouling is determined by the amounts of alkalis in the ash, primarily sodium and potassium compounds that vaporize during combustion and condense at approximately 1700-1500F. • These condensed alkalis act as the glue that bonds dry ash particles together. • Sodium chloride is very active and indicates a fuel with potentially high fouling tendencies. The chlorine is an indicator of the amount of sodium. • Fouling reduces heat transfer, and causes channeling of high velocity gas that erodes the boiler tubes. • High fouling coals should only be used in boilers with wide convection pass spacing, and adequate soot blowing. • Corrosion-chlorine is a halogen and a very good oxidizer. • Furnace tube wastage especially with staged combustion (reducing). Supercritical steam generators worse than subcriticals due to tube metal temperatures. • Stainless Steel Superheaters • FGD stainless steel components
Blending • AEP currently limits Fuel Source Chlorine to 0.2% by weight. • We have completed test burns at a number of facilities that have blending capability and were able to maintain a blend of ILB/Ea. Bit. • Successfully staying below the 0.2% Cl limit • We are comfortable with the “supervised” use of ILB coals • Blending with PRB is difficult because of the sodium in the PRB.