Patent ID: 6071425
Filing Date: 2000-06-06
Classification: B01D

Abstract:
A method of washing a filter fabric of a filter press which includes at least two filtering means and at least two washing means, at least one of said washing means being positioned between adjacent filtering means, said method comprising the steps of:(a) simultaneously, positioning a first portion of said filter fabric in a first filtering means for filtering in a filtration step a material to be filtered containing a liquid and solids through said first portion to form a first filter cake;positioning a second portion of said filter fabric in a first washing means for washing said second portion;positioning a third portion of said filter fabric in a second filtering means for filtering in a filtration step a material to be filtered containing a liquid and solids through said second portion to form a second filter cake; andpositioning a fourth portion of said filter fabric in a second washing means for washing said second portion;(b) filtering a portion of said material to be filtered in said first and second filtering means, thereby retaining the solids on a surface of the first and third portions of said filter fabric thereby forming said first and second filter cakes while said liquid is drained as a filtrate through the first and third portions of said filter fabric and removed from said first and second filtering means, and simultaneously washing said second and fourth portions of said filter fabric in said first and second washing means;(c) following step (b), moving said filter fabric to discharge the first and second filter cakes from above the first and third portions of said filter fabric to one side of the filter press only and to thereafter position said first portion of said filter fabric in said first washing means, said second portion of said filter fabric in said second filtering means and said third portion of said filter fabric in said second washing means; and(d) filtering a further portion of said material to be filtered in said first and second filtering means, thereby forming additional filter cakes while said liquid is drained as a filtrate through portions of said filter fabric and removed from said first and second filtering means, and simultaneously washing said first and third portions of said filter fabric in said first and second washing means.