FILTER PRESS Specification Sheet

 

List of Assumptions:

1.  2.  3.  4. 

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.  



 

5. The dumping, cleaning and reassembling time, thirty [30] minutes.  6.  The operating pressure is 625 kPa.  



of the filter press will be

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 Components Xylose Soluble Lignin Water Sulfuric Acid Total

Mass, Mass, kgs Density, Density, kg/m 13565.80 1525.00 68.88 1300.00 38639.87 995.70 774.65 1825.00 53049.20

Filter Cake Composition: Filter Cake : 28,308.10 kgs

Volume, Volume, m 8.90 0.05 38.81 0.42 48.18

 

Components Unhydrolyzed Pentosan Cellulose Insoluble Lignin Ash Aqueous Solution Total

Mass, kgs 1048.67 12587.71 13847.22 283.18 541.32 28308.10

                    

Filtrate Density,

:

 



Calculation for k value:

Rate of Filtration:

                      

 

                     Rate of Washing:

Since

                  

    

 

Therefore,

       Time of Washing:

 

                  

 

Since the dumping, cleaning and reassembling time,

of the filter press is 30

minutes,  

       

 

             

 

 

For Filtration Area:

                               ()                       

 

 

For viscosity:

 

Cake Resistance: