journal article·2015-08-01

A practical approach to eliminating rapid sodium carbonate - sodium sulfate scaling in black liquor concentrators

W.J. (JIM) FREDERICK, DANIEL D. EUHUS

TAPPI Journal· Volume 14· Issue 7
Publisher page

Abstract

Black liquor concentrators perform as crystallizers as well as evaporators, producing up to 200 kg of sodium carbonate - sodium sulfate double salt (Na2CO3+Na2SO4) crystals per o.d. metric ton of pulp produced. One of these salts, sodium sulfate dicarbonate, rapidly fouls many concentrators as it crystallizes from solution. Design and operation of black liquor concentrators to manage its crystallization can eliminate or substantially reduce sodium sulfate dicarbonate scaling. Older equipment installed before sodium sulfate dicarbonate was discovered in 2002 would benefit the most. This paper explores options for reducing rapid sodium sulfate dicarbonate scaling in black liquor concentrators by applying today’s knowledge of sodium sulfate dicarbonate crystallization characteristics and behavior during crystallizing evaporation.
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Research context

OpenAlex topics: Freezing and Crystallization Processes

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

References (12)

Show source-provided references
1. Grace, T.M., “Survey of Evaporator Scaling in the Alkaline Pulp Industry,” Project 3234, Report 1, The Institute of Paper Chemistry, Appleton, WI, USA, 22 September 1975.
2. Frederick, W.J., in Kraft Recovery Boilers (T.N. Adams, Ed.), TAPPI PRESS, Atlanta, GA, USA, 1997, p. 84.
3. Schmidl, W. and Frederick, W., Int. Chem. Recovery Conf., TAPPI PRESS, Atlanta, 1998, p. 367.
4. Shi, B. and Rousseau, R.W., Ind. Eng. Chem. Res. 40(6): 1541(2001).10.1021/ie0006559 ↗
5. Shi, B., “Crystallization of solutes that lead to scale formation in black liquor evaporation,” Ph.D. thesis, Georgia Institute of Technology, Atlanta, 2002.
6. Verrill, C.L. and Frederick, W.J., “Evaporator Fouling 101 − Sodium salt crystallization and soluble-scale fouling,” TAPPI Eng., Pulping Environ. Conf., TAPPI PRESS, Atlanta, 2005.
7. Euhus, D.D., “Nucleation in bulk solutions and crystal growth on heat-transfer surfaces during evaporative crystallization of salts composed of Na2CO3 and Na2SO4,” Ph.D. thesis, Georgia Institute of Technology, Atlanta, 2003.
8. Frederick, W.J. and T.M. Grace, “Analysis of scaling in a black liquor evaporator,” AIChE Symp. Ser. 184 75: 95(1979).
9. Patel, J-C., “Black liquor evaporators: Design and operation,” Course Notes - Kraft Recovery Short Course, TAPPI PRESS, Atlanta, 2008, Section 3.2.
10. Samant, K.D. and O’Young, L., Chem. Eng. Prog. 102(10): 28(2006).
11. Verrill, C.L., Rousseau, R.W., and Wilkinson, A.P., AIChE Annu. Meet., Conf. Proc., 2005, Paper 470.
12. Olausson, L., Andersson, U., and Gourdon, M., Swedish pat. WO/2011/102761 (2012).