الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
The present work deals with the stUdy of mass transfer characteristics of fluidized bed crystallizers and the role of mass transfer in the performance of these crystallizers. Sodium chloride ’WaS chosen to perform the present stUdy :tu view of its technical importance. Bed flUidization was carried out by either mechanical stirring or gas s’\iirring. Variables studied Yile.re: degree o:f sti..rring ~ temperature and physical properties of the solution. The study revealed the following re sults =
(1) Ra’iie of crystallization increases with increasing degrea of stirring and solution temperature.
(2) The mass transfer coefficient of sodium chloride crystalliz¬a’tiion was found to increase lIuth the degree of stirring (mecha¬nical and air stirring) till it reaches a constant value at high degrees of stirr:L”1g and becomes independant of the degJ:’ee of stirring
(3) The effeot of temperature on the mass transfer coefficient was found ’GO obey Arrhenius equation with an activation energy of 9600 ,9800 caloriEJImole for high degrees of mechanical &’>J.d air stirring respee-ti/e~y.
(4) The study of the effect of the degree of stirring and the
.effect of temperature on the mass transfer coefficient of sodium chloride crystallization? have revealed that sodium chloride crystallization i,a a diffusi.OJi controlled p.t’ocess at relatively low degrees of stirring and chemically controlled at high degrees of s ti.rring.
or (5) Mathem.atica1 anelysis of the mass transfer data using the method of dimensional analysis r~.!sulted :in the following (Ner¬all correlations:
For mechanicallY stirred crysta1lizer, Sh = 0.044 ScO.34,ReO.43
J = 0.75Re••O.50
For gas stir:t’eti cryste,lliz~r,
Sh = 0.45 scO.39.Reo.46 -.()o5”~
J = 0.79Re
(6) For the same rate of crysta11ization~ power consumed in operating gas stirred crysta11ize~’was found to be much less
than that consumed in. operating mechanicalJ~ stirred cr.yp.tnJ~ize~ (7) Crystal size was found to decrease with increasing the degree of st:trr:Lng ond temperatu.re, the size reaches a limiting value
at re1ati~ely high degrees of stirring, T”\th rega~d to crystal size dist.’t’ibu+,~.on, it was found tllat a’~ rela’(;ivel~r low degrees
of s•i;;trring, crystal size tends to be ’mif’orm while at re¬latively high degrees of ntLt’l’:Lng a wide spec7.rum of crystal
size is obtained.