Filter 

 Presses 



heating medium in the first cell and live steam in the second cell. The juice 

 passing from the tubes of the first cell to the tubes of the second is gradually 

 heated to a temperature of about 210 F. 



The heat causes the lime to combine rapidly with the im- 

 Settling purities in the juice, which is discharged into open settling tanks 



where the insoluble solids settle to the bottom, carrying with 

 them vegetable and other matter held in suspension. The lighter substances 

 rise to the surface of the tanks forming a scum. The length of time allowed 

 for settling of the juice in each tank is fixed by the chemist in charge and is 

 usually in the neighborhood of one-half hour. The settling tanks are arranged 

 in rows. As the juice comes from the heater, each tank is filled successively 

 so that by the time the last of the series is being filled, the first tank has had 

 an opportunity to settle, the clear juice has been drawn off, the mud and scum 

 have been washed from the tank and it is ready for refilling. After settling, 

 the clear juice is decanted from the tanks to the evaporator supply tank. In 

 some factories it is passed through a mechanical filter which removes an 

 additional amount of impurities. The mud and scum are drained into other 

 tanks where lime is added. The mass is then stirred and pumped into cachaza 

 tanks where it is again allowed to settle, the clear juice being decanted in the 

 same manner as from the settling tanks. The final mud and other impurities 

 are then pumped to filter presses where an additional amount of clear liquor 

 containing a small portion of sugar is separated. fkncmft UK 



There are a number of different types of filter presses/ out 

 Presses those generally in use at the present time rest horizontally on 



the floor and are made up of layers of cast iron corrugated plates 

 covered with cotton filter cloth laid between the plates and hollow frames. 

 When the press is dressed complete with filter cloths over the corrugated 



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