String discharge

Another variation of the string discharge is the use of a thick plastic belt which is perforated by conical openings. The dmm is covered with filter cloth and the belt covers the cloth for the filtration and dewatering operations. The soHds fill the perforations in the belt and then leave the dmm with the belt to be discharged by air blow as pellets. This is an effective way of pelletising coarse mineral ores. 

String-Discharge Filter A system of endless strings or wires spaced about 13 mm (0.5 in) apai t pass around the filter drum but are... 

Figure 11. Shows a roll discharge. Figure 12.. Shows a string discharge.

A cake discharge mechanism that can be either a scraper, belt, roll and in rare cases a string discharge. Blow is applied only to filters with scraper and roll discharge mechanisms but not to filters with a belt or string discharge,... 

In the string discharge system, the conveyor consists of a number of endless strings which are spaced at a pitch of approximately 12 mm over the width of the filter drum. The string spacing may, however, be in the range 6-25 mm depending on the mechanical properties of the solids. 

A typical string discharge mechanism is shown in Figure 7.20. 

Figure 7.20. String discharge mechanism on a filter handling silica gel...

Cake removal usually is with a scraper into a screw or belt conveyor, but Figure 11.12(d) depicts the use of a drum with a filtering belt that is subject to a continual cleaning process. Some filters have a multi parallel string discharge assembly whose path follows that of the belt shown. 

String discharge filter. (7) Two or three stages of counter-current washing. ... 

Then steam was applied and the temperature was raised to boiling. 200 pounds of coarse filter aid (perlite) was added and the mixture filtered through a string discharge vacuum filter. The cake was washed with 200 gallons of hot water on the filter. 

String discharge filter. (3) Cake washed. (4) Roller discharge drum filter. ... 

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