Solid Waste/Byproducts of Gasification

COMPARISON OF THE ENVIRONMENTAL PERFORMANCE OF IGCC WITH PC AND FLUIDIZED BED POWER PLANTS

Table 5 compares the quantity of solid waste and byproducts produced by integrated gasification combined cycle (IGCC), fluidized bed combustion (FBC), and pulverized coal (PC) plants. The basis for this comparison is a 300 MWe size plant using an Illinois bituminous coal with 4% sulfur content. The IGCC plant is shown to generate significantly less total solids than the other plants, roughly one-half that of the PC plant and one-third that of the FBC plant. Selection of lower coal sulfur content for this analysis will provide a more favorable comparison for the PC and FBC plants relative to the IGCC plant.

Table 5. Solid Waste and Byproduct Comparison for 300 MWe Plants—IGCC vs. PC and FBC Plants

PLANT DATA PC PLANT WITH ADVANCED WET FGD FBC PLANT IGCC PLANT
PLANT OPERATING DATA
Plant Size, MWe 300 300 300
Annual Capacity Factor, % 65 65 65
Heat Rate, Btu/kWh 9,750 9,400 9,000
Carbon Conversion, % 99 98 99
Feed Fuel, tons/day 3,480 3,360 3,216
Feed Limestone, tons/day 466 1,104 -
FUEL PROPERTIES
HHV, Btu/lb 10,100 10,100 10,100
Sulfur, Weight % 4 4 4
Ash, Weight % 16 16 16
Carbon, weight % 57.6 57.6 57.6
SULFUR REMOVAL
Removal Efficiency, % 95 95 98
Sorbent Limestone Limestone MDEA
Limestone Purity, % 95 95 -
Ca/S Molar Ratio 1.02 2.5 -
Water on Dry Waste, % 25 25 25
SOLIDS GENERATED, tons/day
Ash (Dry) 557 538 0
Slag (Dry) 0 0 515
Carbon in Ash (Dry) 20 19 19
Elemental Sulfur 0 0 126
CaSO4 (Anhydrite) 562 542 0
Water in CaSO4•2H20 149 144 0
CaO (Dry) 10 363 0
Water in Ca(OH)2 3 117 0
Inerts from Limestone 23 55 0
TOTALS
TOTAL BY-PRODUCTS,
tons/day
747 0 126
TOTAL SOLID WASTE,
tons/day (Dry)
577 1,778 534
TOTAL SOLIDS
GENERATED, tons/day
1,324 1,778 660
TOTAL SOLIDS GENERATED, lb/MWh 367 494 183
TOTAL SOLID WASTE GENERATED, lb/MWh 172 494 148

 


Solid Waste/Byproducts of Gasification