Belt Filter Apparatus

Abstract

The invention concerns a belt filter apparatus comprising a first belt filter section on which a mixture of fine material and a liquid can be placed hydraulically to create partially dry fine material and a second belt filter section on which the partially dry fine material can be placed in order to undergo a second drying cycle. The belt filter apparatus also includes means for mechanically placing the partially dry fine material from the first belt filter section onto the second belt filter section as well as a liquid collection arrangement for providing fluid communication between the first and second belt filter sections and a vacuum. In use the vacuum dries the fine material by drawing liquid through the permeable fabric of the first and second belt filter sections and into the liquid collection arrangement. The belt filter apparatus includes an agitator formation for increasing the permeability of the fine material to enhance the ability of the liquid to be released from the fine material and be collected by the liquid collection arrangement.

1 - 19 . (canceled) 
   
   
       20 . A belt filter apparatus comprising:
 a first belt filter section on which a mixture of fine material and a liquid can be placed hydraulically in order to undergo a first drying cycle to create partially dry fine material, the first belt filter section including a belt filter of a permeable fabric;   a second belt filter section on which the partially dry fine material can be placed in order to undergo a second drying cycle, the second belt filter section including a belt filter of a permeable fabric;   means for mechanically placing the partially dry fine material from the first belt filter section onto the second belt filter section; and   a liquid collection arrangement for providing fluid communication between the first and second belt filter sections and a vacuum, wherein in use the vacuum dries the fine material by drawing liquid through the permeable fabric of the first and second belt filter sections and into the liquid collection arrangement.   
   
   
       21 . The belt filter apparatus according to  claim 20 , wherein the permeable fabric of the first and/or second belt filter section is a non-woven fabric or a micro-pore fabric. 
   
   
       22 . The belt filter apparatus according to  claim 20 , wherein the permeable fabric of the first and/or second belt filter section includes reinforcing. 
   
   
       23 . The belt filter apparatus according to  claim 20 , wherein the first and second belt filter sections are formed by providing a first set of pulleys and a second set of pulleys about which a single belt filter can be moved. 
   
   
       24 . The belt filter apparatus according to  claim 20 , wherein the means for mechanically placing the partially dry fine material comprises a blower which is located proximate a drop-off point between the first belt filter section and the second belt filter section, in use the blower serving to impart jets of air onto the first belt filter section such that the partially dry fine material on the belt filter can be forced therefrom to fall onto the second belt filter section. 
   
   
       25 . The belt filter apparatus according to  claim 20 , wherein the means for mechanically placing the partially dry fine material comprises a cam which is located proximate a drop-off point between the first belt filter section and the second belt filter section, in use the cam serving to impact on the first belt filter section, thereby forcing the partially dry fine material to fall onto the second belt filter section. 
   
   
       26 . The belt filter apparatus according to  claim 20 , further including an agitator formation for redistributing partially dry fine material on the first belt filter section and/or the second belt filter section. 
   
   
       27 . The belt filter apparatus according to  claim 26 , wherein the agitator formation is provided in the form of at least one blower and/or at least one rotatable cam. 
   
   
       28 . The belt filter apparatus according to  claim 20 , wherein the liquid collection arrangement includes liquid collectors which are locatable below the first and second belt filter sections for collecting liquid which is removed from the fine material during the first and second drying cycles. 
   
   
       29 . The belt filter apparatus according to  claim 28 , wherein the liquid collection arrangement also includes ducting for providing fluid communication between the liquid collectors and a liquid storage container. 
   
   
       30 . A method of drying fine material comprising the steps of:
 providing a mixture of a liquid and fine material;   providing a belt filter apparatus having a first and second belt filter section;   providing a vacuum which is in fluid communication with the first and second belt filter section;   hydraulically placing the mixture of liquid and fine material on the first belt filter section;   allowing the mixture of liquid and fine material to undergo a first drying cycle on the first belt filter section to form partially dry fine material;   mechanically placing the partially dry fine material on the second belt filter section; and   allowing the partially dry fine material to undergo a second drying cycle on the second belt filter section.   
   
   
       31 . The method of drying fine material according to  claim 30 , wherein the mixture of liquid and fine material is coal slurry.