Page 343 - Chemical Process Equipment - Selection and Design
P. 343

Feed ~ondition~
                                                                 Product Pa~a~e~ers                         Favoring Use
                                                        Solids      Liquid
                                                       in Liquid   in Solid      Wash*            Solids        Solids     Particle
                                                       Product     Product     Possibilities   Concentration                Size       Bower      Space      Holdup      Bnitiaii   Operating   Maintenance
                                    Filtration
                                     Vacuum drum          F           G            Ed             high to         -        medium       high      medium    medium       high        high        medium
                                      filter                                                        med.
                                     Disc filters         F           G           Pto F          medium           -          fine       high      medium    medium     med. to       high        medium
                                                                                                                                                                         high
                                     Horizontal           F           G          G to Ed          high to         -         coarse      high      medium    medium     medium        high        medium
                                      filter                                                        med.
                                     Precoat filter       E          P**         P to F**        very low         -         slimy      high to    medium    medium       high      very high     medium
                                                                                                                                        med.
                                     Leaf (Kelly)       G to Ed       F           F to G           low            -          fine,     med. to    medium    medium      medium     very high     medium
                                       filter                                                                                 slimy     low
                                    Sedimentation


                                     Thickener          G to E        P             P            medium         dense      medium        low       very       vev      med. to       low         very low
                            0                                                                                                                        high       high     low
                            U        Clarifier            G           P           very P           low          med.         fine       very       very       very     med. to       low         very low
                                                                                                                  dense                   low        high       high     low
                                     Classifier           P           P           Pto F          medium         dense       coarse       low       high       high     med. to       low           low
                                                                                                                                                                         low
                                    Centrifugation
                                     Disc               FtoG          P             P           low to med.    medium        fine       high        low        low       high        high          high
                                     Solid bowl           P           F           Pto F         med. to high   medium      med. to      high        low        low     med. to       high          high
                                                                                                                             fine                                        high
                                     Basket              P  to F      E             Ed          med. to high      -         coarse      high        low        low      medium       high          high

                                    Liquid cyclones
                                     Large                P         Pto F           P           low to med.      high      medium      med. to      low        low     very low     medium         high
                                                                                                                                         low
                                     Small multiple      Pto F        P           very P            low        med. to       fine      med. to      low        low        lOW       medium       medium
                                                                                                                 high                    low
                                    Screens               P         P to F          P           med. to high      -       coarse to      low       very       very       very       medium     med. to high
                                                                                                                            med.                     low        low        low
                                    Ultrafiltration       E         Pto F           P               low           -        very fine   med. to     high       high       high        high        very high
                                                                                                                                         high

                                      a P = Poor. F = Fair. G = Good. E = Excellent. * Decantation wash always possible.  Displacement wash feasible. ** Solids product contaminated by precoat material.
                                      (Purchas, 1981).
   338   339   340   341   342   343   344   345   346   347   348