Five litres of a 10% (w/w) slurry of chalk (p.-2670 kg/m) in water (u=0.001 Pa-s) was...

 

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Five litres of a 10% (w/w) slurry of chalk (p.-2670 kg/m) in water (u=0.001 Pa-s) was filtered on a filter leaf of 0.03 14 m area. The specific surface of the chalk is 3106 m, and the cake can be assumed to have a porosity of 50%. Dry mass per filtrate volume is 116 kg/m. The filtration was practised at a constant rate until 2.3 litres of filtrate had been recovered. The following empirical equation for pressure was observed: AP=168 (Pa/s) t (s) + 6670 (Pa) Assume an incompressible filtration. (1) The pressure drop over the medium during the filtration (Pa)? (2) The time taken to achieve the filtration to this stage and the constant filtrate rate? (3) The medium resistance (m-)? After the 2.3 litres of filtrate was recovered; the pressure was kept constant until all the suspension was filtered to recover remaining 2.3 liters of filtrate. The resistance of the preformed cake (during the constant rate filtration) should be added into the medium resistance, which results a so-called effective medium resistance, Rm = Rm + caV/A. (4) The total filtration pressure (Pa) after collecting the 2.3 liter of filtrate? (5) The new effective medium resistance? (6) The time required to filter the remaining slurry? (7) The total filtration time to process the 5 L slurry? Five litres of a 10% (w/w) slurry of chalk (p.-2670 kg/m) in water (u=0.001 Pa-s) was filtered on a filter leaf of 0.03 14 m area. The specific surface of the chalk is 3106 m, and the cake can be assumed to have a porosity of 50%. Dry mass per filtrate volume is 116 kg/m. The filtration was practised at a constant rate until 2.3 litres of filtrate had been recovered. The following empirical equation for pressure was observed: AP=168 (Pa/s) t (s) + 6670 (Pa) Assume an incompressible filtration. (1) The pressure drop over the medium during the filtration (Pa)? (2) The time taken to achieve the filtration to this stage and the constant filtrate rate? (3) The medium resistance (m-)? After the 2.3 litres of filtrate was recovered; the pressure was kept constant until all the suspension was filtered to recover remaining 2.3 liters of filtrate. The resistance of the preformed cake (during the constant rate filtration) should be added into the medium resistance, which results a so-called effective medium resistance, Rm = Rm + caV/A. (4) The total filtration pressure (Pa) after collecting the 2.3 liter of filtrate? (5) The new effective medium resistance? (6) The time required to filter the remaining slurry? (7) The total filtration time to process the 5 L slurry?