Study of soluble scale fouling control in high solids black liquor concentrators. Progress report, quarter 5 (October 1, 1999 - December 31, 1999)

Abstract

SummaryDuring this quarter, work has finally resumed on the black liquor volubility experiments (Task A. 1), but no new data have yet been generated. The crystallization experiments with inorganic model solutions (Task B. 1) have been completed, and crystallization experiments with kraft black liquor (Task B.2) have been started. The Annular Test Cell (ATC) apparatus is now fully operational, while construction of the falling film evaporator pilot plant (Task C. 1) is nearly complete. Startup of this unit is planned for late in Quarter 6. In the CFD model development work (Task D.2), the relaxation of simpli~ing assumptions in the falling film model have been completed, and expressions were developed to estimate film velocity/tihn Reynolds number relations. Also, thin film data taken for a range of conventional fluids were compared to predictions using selected methods, and attempts were initiated to extrapolate to approximate black liquor evaporator conditions.

Reactivity and porosity development during pyrolysis and physical activation in CO2 or steam of kraft and hydrolytic lignins

“…However, we note that for the 650 8C ashes the positions and relative intensities of 11 peaks match JCPDS powder diffraction file 00-024-1138 for sodium carbonate sulfate, Na 2 CO 3 ÁNa 2 SO 4 . Other double salts, including Na 2 CO 3 Á2Na 2 SO 4 (JCPDS powder diffraction file 00-024-1139) and others which are known to be formed from kraft black liquor [58], give XRD patterns which are notably different [59] and are clearly not present. The diffraction patterns of the 815 8C ashes are more complex, suggesting that decomposition of the sodium carbonate sulfate occurred and that new crystalline phases were formed.…”