Abstract—In this paper, the drying of black liquor droplets
sprayed into the chemical recovery boiler in a pulp and paper mill
is examined. The fate of the droplets in the recovery boiler is
generally divided into three consecutive stages i.e., drying,
devolatilization and char combustion. Drying refers to the
removal of water from the black liquor droplets by upward
moving hot gases during its flight in the recovery boiler. When
the black liquor is atomized in the hot ambience of the recovery
boiler, different sizes of droplets are generated, some of which are
not desirable with regard to incomplete drying. This creates
problems in operation of the recovery boiler. A simple
mathematical model is developed to estimate the travel time from
the point of injection to the char bed. Simulations were carried
out for various parameters including droplet size and suitable
droplet sizes determined for safe and economical boiler
operation.
Index Terms—Black liquor, drying, modeling, recovery boiler,
droplet size
The authors are with the Department of Chemical Engineering, Jaypee
University of Engineering & Technology, A-B Road, Dt. Guna - 473226, M. P.,
India (tel.: +91 7544 267310; fax: +91 7544 267011; e-mail:
hari.mahalingam@juet.ac.in).
[PDF]
Cite: S. Ramesh, H. Mahalingam, and N. J. Rao, "Mathematical Modeling of Drying of Black Liquor Droplets in Recovery Boilers," International Journal of Chemical Engineering and Applications vol. 5, no. 1, pp. 1-5, 2014.
