Method for Separating Liquid From Suspended Matter in a Sludge and Device for Same

Abstract

The invention relates to a method for separating the liquid part from the suspended matter in a sludge supplied in a continuous flow at a flow rate of Q EB =V/hour. The flow is divided into at least two partial flows which are sprayed on top of one another into a sealed chamber of volume v<V/ 20 , simultaneously injecting air therein at a flow rate d, said chamber being kept under overpressure conditions. The suspended matter of the thus treated flow is then left to decant in a collection container, with the cake or solid part falling to the bottom and separating from the liquid part which is continuously discharged.

1 . An apparatus for extracting liquid from a mineralized sludge, wherein the apparatus comprises:
 means for injecting, into a closed chamber, a continuous flow of the mineralized sludge at a rate Q EB =V/h, wherein V is a volume, wherein the closed chamber has an outlet and a volume of v<V/20;   means for, when the device is in operation, maintaining the closed chamber in overpressure relative to atmospheric pressure;   means for injecting, into the closed chamber, air at a rate  d , wherein the injecting of the continuous flow, the injecting of the air, the volume v, and the overpressure of the closed chamber are arranged to create a turbulent mixing of the continuous flow within the closed chamber, wherein the turbulent mixing results in a mixture; and   tubular means for discharging, from the closed chamber via the outlet, the mixture to a collection container, wherein the collection container is configured to enable the mixture to separate into solids and the liquid, and wherein the collection container comprises means for discharging the liquid continuously by gravity.   
     
     
         2 . The apparatus according to  claim 1 , wherein the rate d is greater than 1.5 Q EB . 
     
     
         3 . The apparatus according to  claim 1 , wherein the means for injecting the continuous flow into the closed chamber comprises at least two opposite orifices that are facing each other and are situated in a bottom half of the closed chamber. 
     
     
         4 . The apparatus according to  claim 1 , wherein the means for maintaining the closed chamber in overpressure comprises an overpressure valve. 
     
     
         5 . The apparatus according to  claim 1 , wherein the means for discharging the liquid part by gravity comprises a gravity overflow device. 
     
     
         6 . The apparatus according to  claim 1 , wherein v is less than or equal to V/50. 
     
     
         7 . The apparatus according to  claim 1 , wherein v is less than or equal to V/100. 
     
     
         8 . The apparatus according to  claim 1 , further comprising means for feeding a liquid reagent at a given rate into the closed chamber. 
     
     
         9 . The apparatus according to  claim 1 , wherein the rate Q EB  is greater than or equal to 15 m3/h, the rate d is greater than or equal to 23 m3/h, and the overpressure is greater than or equal to 0.8 bar. 
     
     
         10 . The apparatus according to  claim 9 , wherein the rate Q EB  is greater than or equal to 20 m3/h, the rate d is greater than or equal to 50 m3/h, and the overpressure is greater than 1.2 bar. 
     
     
         11 . The apparatus according to  claim 1 , further comprising means for degassing, via a second outlet of the closed chamber, and directing gasses such that the gasses feed air injection at the bottom part. 
     
     
         12 . The apparatus according to  claim 1 , further comprising means for treating the solids to obtain a solidified pancake. 
     
     
         13 . An apparatus for extracting liquid from a mineralized sludge, wherein the apparatus comprises:
 a collection chamber;   a closed chamber that has an outlet and a volume of v<V/20, wherein V is a volume;   a valve that is arranged at the outlet and that is configured to maintain the closed chamber in overpressure relative to atmospheric pressure;   a transfer component between the closed chamber and the collection chamber;   wherein the closed chamber is configured to:
 receive, via a first injection at a rate Q EB =V/h, a continuous flow of the mineralized sludge, and 
 receive, via a second injection at a rate d, air; 
   wherein the continuous flow, the air, the volume v, and the overpressure of the closed chamber are arranged to create a turbulent mixing of the continuous flow within the closed chamber, wherein the turbulent mixing results in a mixture;   wherein the transfer component is configured to receive, from the closed chamber via the outlet, a discharge of the mixture and provide, to the collection container, the discharge of the mixture; and   wherein the collection container is configured to:
 enable the mixture to separate into solids and the liquid, and 
 discharge, via gravity, the liquid continuously. 
   
     
     
         14 . The apparatus according to  claim 13 , wherein the rate d is greater than 1.5 Q EB . 
     
     
         15 . The apparatus according to  claim 13 , wherein the closed chamber is configured to receive the continuous flow of the mineralized sludge via at least two opposite orifices that are facing each other and are situated in a bottom half of the closed chamber. 
     
     
         16 . The apparatus according to  claim 13 , wherein the valve comprises an overpressure valve. 
     
     
         17 . The apparatus according to  claim 13 , wherein v is less than or equal to V/50. 
     
     
         18 . The apparatus according to  claim 13 , wherein the rate Q EB  is greater than or equal to 15 m3/h, the rate d is greater than or equal to 23 m3/h, and the overpressure is greater than or equal to 0.8 bar. 
     
     
         19 . An apparatus for extracting liquid from a mineralized sludge, wherein the apparatus comprises:
 means for injecting at least two partial flows of the mineralized sludge into a closed chamber, wherein the at least two partial flows form a continuous flow having a rate Q EB =V/h, wherein V is a volume, wherein the closed chamber has a volume of v<V/20;   means for injecting air into the closed chamber, wherein the injecting of the at least two partial flows and the injecting of the air causes (a) a turbulent mixing of the at least two partial flows that results in a mixture and (b) an increase of an internal pressure of the closed chamber;   means for discharging, via an outlet of the closed chamber and after the internal pressure of the closed chamber has exceeded a threshold pressure, a portion of the mixture from the closed chamber and to a collection container;   the collection container configured to collect the portion of the mixture to allow for separation of solids and the liquid; and   means for continuously discharging the liquid from the collection container.   
     
     
         20 . The apparatus of  claim 19 , wherein the means for discharging comprises a discharge valve.