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List of Assumptions: 1. 2. 3. 4. 5.

The resistance of the filter medium is zero. The volume of wash water is 10% of the total volume of filtrate. Filtration is carried out in batch operation [1 batch per day]. The time of filtration, will be four [4] hours. The dumping, cleaning and reassembling time, of the filter press will be thirty [30] minutes. 6. The operating pressure is 625 kPa.

Design Equations: 

Filtrate Density,

Where:



k Value Assume: Rm = Resistance of the filter medium = 0 Ve = fictitious volume of filtrate per unit of filtering area = 0 t

= time of filtration = 4 hrs (



Rate of Filtration,



Rate of Washing,



Time of Washing,

)

Where:



Total Filtration Time



Calculation for the Area of Filtration (Ref: Plant Design and Economics for Chemical Engineers by Peters and Timmerhaus pages 543-545) ( )



Cake Resistance, (Ref: Plant Design and Economics for Chemical Engineers by Peters and Timmerhaus pages 543-545) (

)

= constant with value dependent on the property of solid material

Design Calculations: From Material Balance: Filtrate Composition: Components Mass, kgs Density, kg/m3 Volume, m3 13565.80 1525.00 8.90 Xylose 68.88 1300.00 0.05 Soluble Lignin 38639.87 995.70 38.81 Water 774.65 1825.00 0.42 Sulfuric Acid Total 53049.20 48.18 Filter Cake Composition: Filter Cake : 28,308.10 kgs

Components Unhydrolyzed Pentosan Cellulose Insoluble Lignin Ash Aqueous Solution Total Filtrate Density,

Mass, kgs 1048.67 12587.71 13847.22 283.18 541.32 28308.10

: (

)

Calculation for k value: (

)

(

)

Rate of Filtration:

(

)

Rate of Washing: (

)

Since Therefore, (

)

Time of Washing:

Since the dumping, cleaning and reassembling time, minutes,

of the filter press is 30

For Filtration Area: (

)

For viscosity: (

)

(

(

) )

Cake Resistance: (

)