Apparatus and method for transferring and pressurizing powder

Abstract

The invention relates to an apparatus for transferring a powdered material from a first zone under pressure PI to a second zone under pressure P 2 and for pressurizing the powdered material from pressure PI to pressure P 2 . The present invention may impart movement, such as oscillations, to the powdered material typically to avoid packing of the powdered material during transfer.

1 . An apparatus for transferring a powdered material from a first zone under first pressure P 1  to a second zone under a second pressure P 2 , and for pressurizing the powdered material from pressure P 1  to pressure P 2 , the apparatus comprising a receptacle equipped with a powder inlet between the first zone and the receptacle, a powder outlet between the receptacle and the second zone, a gas inlet and a gas outlet, a closure adapted to selectively seal the receptacle from first zone, second zone or both zones, during transfer and pressurization of the powdered material, the receptacle is equipped with an oscillator positioned upstream of the powder outlet, wherein the oscillator is adapted to be actuated during discharge of the powdered material, and wherein the oscillator thus imparts oscillations to the powdered material during discharge thereof. 
     
     
         2 . The apparatus according to  claim 1 , wherein said oscillator comprises a rotatable flap arranged in the receptacle and extending perpendicular to the direction of powder discharge, wherein the rotatable flap may be positioned in an ajar position, and wherein the rotatable flap may be actuated to oscillate around its ajar position during powder discharge. 
     
     
         3 . The apparatus according to  claim 2 , wherein the rotatable flap is actuated by an actuator without hysteresis. 
     
     
         4 . The apparatus according to  claim 2 , wherein the actuator is a pneumatic actuator. 
     
     
         5 . The apparatus according to  claim 2 , wherein the oscillator is butterfly valve. 
     
     
         6 . The apparatus according to  claim 1 , wherein the receptacle is equipped with at least two gas inlets, at least one of which is positioned between the oscillator and the powder outlet. 
     
     
         7 . The apparatus according to  claim 1 , wherein the receptacle is equipped with a filter capable of retaining the powdered material and which defines within the receptacle:
 a head space which is provided with the gas outlet, and   a working space which is provided with the powder inlet and the powder outlet.   
     
     
         8 . The apparatus according to  claim 7 , wherein the head space is provided with a gas inlet. 
     
     
         9 . The apparatus according to  claim 1 , wherein the receptacle is equipped with a plurality of gas inlets connected to a single gas supply through respective gas pipes. 
     
     
         10 . The apparatus according to  claim 9 , wherein the gas pipes are arranged in parallel from the gas supply to the gas inlets. 
     
     
         11 . The apparatus according to  claim 9 , wherein the gas pipes are equipped with a closure. 
     
     
         12 . The apparatus of  claim 11 , wherein the closure of the gas pipes may be controlled for simultaneous opening or closing. 
     
     
         13 . The apparatus according to  claim 1 , wherein the apparatus comprising a tapering member between the oscillator and the powder outlet. 
     
     
         14 . The apparatus according to  claim 1 , wherein the oscillator adapted to oscillate with a frequency between 0.5 Hz and 30 Hz. 
     
     
         15 . The apparatus according to  claim 1 , wherein the oscillator adapted to oscillate with an amplitude between 1 degrees and 20 degrees. 
     
     
         16 . The apparatus according to  claim 1 , wherein the apparatus being adapted to operate with an absolute difference in pressure between the first pressure P 1  and the second pressure P 2  of at least 10 bars. 
     
     
         17 . A pressurised apparatus according to  claim 1 , wherein the absolute difference in pressure between the first pressure P 1  and the second pressure P 2 ,  1 P 2 -P 11 , is at least 10 bars. 
     
     
         18 . A method of transferring a powdered material from a first zone under pressure P 1  to a second zone under pressure P 2  by use of an apparatus comprising a receptacle equipped with a powder inlet between the first zone and the receptacle, a powder outlet between the receptacle and the second zone, a gas inlet and a gas outlet, a closure adapted to selectively seal the receptacle from first zone, second zone or both zones, during transfer and pressurization of the powdered material, the receptacle is equipped with an oscillator positioned upstream of the powder outlet, wherein the oscillator is adapted to be actuated during discharge of the powdered material, and wherein the oscillator thus imparts oscillations to the powdered material during discharge thereof, the method comprising:
 filling the apparatus with powdered material from the first zone by feeding powdered material into the receptacle while the powder inlet being open, the powder outlet being closed, the gas outlet being opened; 
 pressurizing the apparatus by feeding pressurised gas into the apparatus through one or more gas inlets while the powder inlet, the powder outlet and the gas outlet being closed; and 
 emptying the apparatus by opening the powder outlet, activating the oscillator.