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300                                                      Chapter 6



                 5.04  kg  1  m 3
                                             3
                                          3
                                                      3
               = ————   ————— = 5.040xlO~  m /s  (0.178 ft /s)
            V H
                  1  s  1000  kg
            Table 6.4.1  Properties of Water-Oil Mixtures
                               Property    Oil      Water



                              P (kg/m 3    897       1000
                              n(Pa-s)     0.01     7.0x1 0" 4
                              m (kg/s)     1.26      5.04
                              d(m)       ISOxlO" 6
                              t R(s)       300





                Follow the procedure given in Table 6.16.  Step  1, requires determining the
            dispersed phase.  From Equation 6.15.1,

               1.405xlO~  897  7X10"  , 0.3
            e  =  -                       = 0.1215
               5.040xlO~ 3  UOOO  0.01 )
                 Therefore, according to Table 6.13  the light phase or oil is dispersed, and the
            heavy phase or water is continuous. Therefore, from Equations 6.15.2 to 6.15.6,

            V D = V L, V D = V L, p D = p L, p c = p H, and  Uc =  HH-

                Now,  calculate  the  decanter  diameter.  After  substituting  A  from  Equation
                                                                L
            6.15.14 into Equation 6.15.16, the superficial velocity for the light phase,
            v L = 8V L /7iD 2

                Next, substitute this equation and Equation 6.15.20 into Equation 6.15.18.
            Thus, the Reynolds number for light phase,


                  8p L V L
            Re L = —————






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