This filtration operation is utilized in the following unit procedures: Nutsche Filtration, Basket Centrifugation, and Plate and Frame Filtration.
● Nutsche Filtration Procedure
● Plate and Frame Filtration Procedure
● Centrifugation in a Basket Centrifuge (Top Discharge) Procedure
● Centrifugation in a Basket Centrifuge (Bottom Discharge) Procedure
The material balances are based on the removal percentage of particulate components and the cake dryness. More specifically, the removal percentage of particulate components determines the amount of those components that is retained in the cake. The cake dryness expressed as Loss On Drying (LOD) % or Cake Porosity determines the amount of solvent and soluble components retained in the cake before washing. Alternatively, you have the option to specify the directly the solvent percentage that is retained by the cake.
Notice that if a Cake Wash operation is available in the same procedure, the amount and type of washing determines the displacement of solvent from the cake.
In design mode of calculation, the process (filtration) time (tp) is specified by the user and the filter area (A) is calculated by using eq. (A.104).
In rating mode, the user specifies the filter area and the number of units and the program calculates either the average filtrate flux (when the filtration time is specified) or the filtration time (when the flux is specified).
The cake thickness is calculated by dividing the cake volume per cycle by the filter area. If the calculated cake thickness exceeds the user-specified maximum cake thickness, the user is warned.
Cake discharge can be modeled using a Transfer Out operation in the same procedure.
To account for any power requirement for agitation, vacuum, etc. the user can provide a value for the specific power requirement in kW per m2 of filter area or simply specify the power consumed.
The interface of this operation has the following tabs:
● Oper. Cond’s, see Cloth Filtration: Oper. Conds Tab
● Labor, etc, see Operations Dialog: Labor etc. Tab
● Description, see Operations Dialog: Description Tab
● Batch Sheet, see Operations Dialog: Batch Sheet Tab
● Scheduling, see Operations Dialog: Scheduling Tab