Influence of pressure on pyrolysis of black liquor: 2. Char yields and component release.
This is the second in a series of papers concerning the behavior of black liquor during pyrolysis at elevated pressures. Two industrial black liquors were pyrolyzed under pressurized conditions in two laboratory-scale devices, a pressurized single-particle reactor and a pressurized grid heater. Temperatures ranging between 650 and 1100 degrees C and pressures in the range 1-20 bar were studied. Char yields were calculated and based on analysis of some of the chars the fate of carbon, sodium, potassium and sulfur was determined as a function of pyrolysis pressure. At temperatures below 800 degrees C little variation in char yield was observed at different pressures. At higher temperatures char yield increased with pressure due to slower decomposition of sodium carbonate. For the same reason, sodium release decreased with pressure. Sulfur release, however, increased with pressure primarily because there was less opportunity for its capture in the less-swollen chars.
Whitty
Kevin
K
Department of Chemical Engineering, University of Utah, 50 S. Central Campus Drive, Room 3290, Salt Lake City, UT 84112, USA. kevin.whitty@utah.edu
Kullberg
Mika
M
Sorvari
Vesa
V
Backman
Rainer
R
Hupa
Mikko
M
D004602:Elements; D007220:Industrial Waste; D011312:Pressure; D013696:Temperature; D013818:Thermogravimetry
D004602:Elements; D007220:Industrial Waste