Cloth Filtration: Oper. Conds Tab

Variable Definitions, Ranges and Default Values

The following table shows a brief description of the variables appearing in this tab. The table also displays their default values and their generally acceptable range:

Variable	Default Value	Range

○ % Removed The percentage of a particulate component that is removed.	0.0	0-100
◙ LOD (%) The amount of volatile components in a cake sample measured using a Loss On Drying (LOD) test.	30.0	0 – 100
◙ Cake Porosity The fraction of void spaces in the cake over the total volume of the cake.	0.4	0 – 1
◙ Solvent Retained The percentage of solvent that is retained by the cake.	20	0 – 100
○ Max. Cake Thickness (cm) The maximum thickness of the cake.	15.0	Positive
● Cake Thickness (cm) The thickness of the cake.	0.0	Positive
○ Setup Time The amount of time (per cycle) spent before each operation is carried in preparation for the actual execution of the operation. It may involve actions like cleaning, vacuuming, setting up of equipment, etc. which the user opted not to model explicitly.	0.0	Positive
◙ Filtration Time (min) The actual duration of the operation (per cycle).	240.0	Positive
◙ Filtrate Flux (L/m²-h) The volumetric flow rate of the filtrate per filter area. Note that this value is always set in Design Mode.	200.0	Positive
○ Filtrate Stream Indicates the output port that is connected to the stream which is used to transfer out the filtrate. Click on the list box to bring up a list of available output ports in order to select one.	<none>	Any Output Port
○ Power Type Indicates the power type that is used by the operation. Click on the list box to bring up a list of available power types in order to select one.	<Std Power>	Any Power Type
◙ Specific Power (kW/m³) The power consumed for the operation per filter area.	0.1	Positive
◙ Total Power (kW) The total power consumed for the operation (per cycle).	0.0	Positive
◙ Power Per Unit (kW) The power consumed for the operation per equipment unit.	0.0	Positive

Symbol Key: ○ User-specified value (always input); ● Calculated value (always output); ◙ Sometimes input, sometimes output

Specification Choices / Comments

The following list describes the available specification choices in this tab; for more details on how these are implemented, see Cloth Filtration: Modeling Calculations.

•Filtration Time Options...

In Rating Mode (specified equipment size), the user has the option of setting either the Filtration Time or the Average Filtrate Flux.

•Cake Dryness/Solvent Retention...

Cake dryness is specified either in terms of Loss-On-Drying (LOD) or as Cake Porosity. Solvent retention is specified as percentage of the initial amount.

•Filtrate Port / Stream...

The availability of multiple filtrate streams enables the user to segregate filtrate and wash liquids.

•Cake Thickness...

The max cake thickness is a constraint. If the calculated value exceeds the max, the user is warned.

•Filtration Mode...

If the Draw-and-Filter option is selected then it is assumed that the operation works in continuous mode where the material is simultaneously transfered-in and filtered. In this case, an input stream must be specified. On the other hand, if the Filter Contents option is selected, it is assumed that the filtration works with contents already in the vessel. In this case, the material must be transfered-in before the filtration operation i.e., by a charge or transfer-in operation. Notice that in both cases an equipment volume will be calculated based on the filter area and user-specified height. However, if the draw and filter mode has been selected there will not be any warnings generated in case the equipment volume is lower than the volume of the contents.