Sizing of Clarification Tank

Sizing Clarification tank

Mill capacity,                                     C_m1      :           40 MT/ hr

Diluted crude oil to FFB,                 n          :           65 %

Diluted Crude oil,                             T_CO      =          C_m1 x n

                                                                        =          40 x 0.65

                                                                        =          26 MT/ hr

Retention time,                                 RT       :           6 hours

Safety factor,                                     k          :           1.2

Capacity of clarification tank                     =          T_CO x RT x k

                                                                        =          26 x 6 x 1.2

                                                                        =          187.2 MT

                                                                        ~          190 MT

Assume

                        Empty space,            A         :           1 ft (0.33m)

                        Oil Layer                    B         :           1 ft (0.33m)

                        Sludge Layer                        C         :           distance of oil droplets travel

Oil particle size & %             :           90 % > 60 micron

                                                                        :           10 % < 60 micron

According to Stork’s Law                           

Velocity of rise,         v          :           125 micron/ sec

Retention time,         RT       :           6 hrs

Distance of travel, c             =          v x RT

                                                =          125 x 6 x 3600

                                                =          2700 mm

Total length of clarifier feed pipe              =          A + B + C

                                                                        =          (0.33) + (0.33) + (2.7)

                                                                        =          3.36 m

Height of clarifier tank,                    H         =          2 x 3.36

                                                                        =          6.8 m

Diameter of clarifier                         D         =        

                                                =          6.2 m