Stirrer

Abstract

An agitator is capable of more efficiently applying a shear force to a treatment target fluid through the action of an intermittent jet flow. The agitator includes a rotor which includes blade, and a screen concentric therewith, the rotation of at least the rotor causing a treatment target fluid to pass through slits in the screen to become an intermittent get stream, which is discharged from inside the screen to the outside thereof, wherein the agitator is characterized in that: the screen has a cylindrical shape with a circular cross section; openings of the slits provided in an inner surface of the screen constitute flow intake openings; openings of the slits provided in an outer surface of the screen constitute flow discharge openings; spaces between the flow intake openings and the flow discharge openings constitute slit space; and the circumferential-directional width (So) of the flow discharge openings and the circumferential-directional width (Si) of the flow intake openings are greater than the circumferential-directional width (Sm) of the slit spaces.

1 . A stirrer which comprises:
 a rotor having a plurality of blades and rotating, a partition wall for the purpose of holding a discharge pressure of the rotor, and a screen laid around the rotor, all of which are provided concentrically,   the screen comprises a plurality of slits in a circumferential direction thereof and a screen member located between the adjacent slits, and   in the stirrer in which, of the rotor and the screen, by rotating at least the rotor, a fluid to be processed is discharged as an intermittent jet flow from an inside to an outside of the screen through the slit, wherein   the screen forms a cylindrical shape having a circular cross-section, and   an opening of the plurality of slits provided on an inner wall surface of the screen is made to serve as an inflow opening, and an opening of the plurality of slits provided on an outer wall surface of the screen is made to serve as an outflow opening, and a space between the inflow opening and the outflow opening is made to serve as a slit space, wherein   a width (So) of the outflow opening in the circumferential direction and a width (Si) of the inflow opening in the circumferential direction is set so as to be larger than a width (Sm) of the slit space in the circumferential direction.   
     
     
         2 . The stirrer according to  claim 1 , wherein
 the plurality of the slits includes at least an inflow-side region where the fluid to be processed flows into the slit from an inner side of the screen and an outflow-side region where the fluid to be processed flows out from the slit to an outside of the screen, and   the inflow-side region is defined by an inflow-side end surface in a front side and an inflow-side end surface in a rear side, which are arranged with a distance in a rotation direction of the plurality of the blades, and the outflow-side region is defined by an outflow-side end surface in the front side and an outflow-side end surface in the rear side, which are arranged with a distance in the rotation direction of the blades, wherein   the width (Sm) of the slit space in the circumferential direction is a width of the narrowest narrow part of the slit space in the circumferential direction; and angle of at least one of the following (1) to (4) is in the range of 1 degree to 45 degrees:   (1) an angle of the inflow-side end surface in the front side against a radius passing through a center of the narrow part in the circumferential direction,   (2) an angle of the outflow-side end surface in the rear side against a radius passing through a center of the narrow part in the circumferential direction,   (3) an angle of the inflow-side end surface in the rear side against a radius passing through a center of the narrow part in the circumferential direction, and   (4) an angle of the outflow-side end surface in the front side against a radius passing through a center of the narrow part in the circumferential direction.   
     
     
         3 . The stirrer according to  claim 2 , wherein
 the plurality of the slits is provided with an intermediate region formed between the inflow-side region and the outflow-side region, the intermediate region is defined by an intermediate end surface in the front side and an intermediate end surface in the rear side, which are arranged with a distance in the rotation direction of the plurality of the blades, and the intermediate end surface in the front side and the intermediate end surface in the rear side have a width in a radial direction.   
     
     
         4 . The stirrer according to  claim 1 , wherein
 the width (Sm) of the slit space in the circumferential direction is the width of the narrowest narrow part in the circumferential direction among the width of the slit space in the circumferential direction; and   the width of the slit in the circumferential direction is gradually decreased from the inflow opening toward the narrow part and is gradually increased from the narrow part toward the outflow opening.   
     
     
         5 . The stirrer according to  claim 1 , wherein the width (So) of the outflow opening in the circumferential direction is in the range of 1.0 mm to 8.0 mm. 
     
     
         6 . The stirrer according to  claim 1 , wherein diameters of the blade and of the screen are decreased as departing in an axial direction from an introduction port through which the fluid to be produced is introduced into the screen. 
     
     
         7 . The stirrer according to  claim 1 , wherein
 the plurality of the slits has the same width in the circumferential direction and are formed with an equal distance in the circumferential direction, and   the screen does not rotate.   
     
     
         8 . The stirrer according to  claim 1 , wherein
 the plurality of the slits has the same width in the circumferential direction and are formed with an equal distance in the circumferential direction, and   the screen rotates in a direction opposite to the rotor.   
     
     
         9 . The stirrer according to  claim 1 , wherein
 a width (v) of the plurality of the slits in the screen in the radial direction thereof is defined by the following formula (1), when D is a maximum outer diameter of the rotor,
   0.02× D≤v≤ 0.15× D   (1).
 
   
     
     
         10 . The stirrer according to  claim 2 , wherein
 the width (Sm) of the slit space in the circumferential direction is the width of the narrowest narrow part in the circumferential direction among the width of the slit space in the circumferential direction; and   the width of the slit in the circumferential direction is gradually decreased from the inflow opening toward the narrow part and is gradually increased from the narrow part toward the outflow opening.   
     
     
         11 . The stirrer according to  claim 3 , wherein
 the width (Sm) of the slit space in the circumferential direction is the width of the narrowest narrow part in the circumferential direction among the width of the slit space in the circumferential direction; and   the width of the slit in the circumferential direction is gradually decreased from the inflow opening toward the narrow part and is gradually increased from the narrow part toward the outflow opening.   
     
     
         12 . The stirrer according to  claim 2 , wherein the width (So) of the outflow opening in the circumferential direction is in the range of 1.0 mm to 8.0 mm. 
     
     
         13 . The stirrer according to  claim 3 , wherein the width (So) of the outflow opening in the circumferential direction is in the range of 1.0 mm to 8.0 mm. 
     
     
         14 . The stirrer according to  claim 4 , wherein the width (So) of the outflow opening in the circumferential direction is in the range of 1.0 mm to 8.0 mm. 
     
     
         15 . The stirrer according to  claim 2 , wherein diameters of the blade and of the screen are decreased as departing in an axial direction from an introduction port through which the fluid to be produced is introduced into the screen. 
     
     
         16 . The stirrer according to  claim 3 , wherein diameters of the blade and of the screen are decreased as departing in an axial direction from an introduction port through which the fluid to be produced is introduced into the screen. 
     
     
         17 . The stirrer according to  claim 4 , wherein diameters of the blade and of the screen are decreased as departing in an axial direction from an introduction port through which the fluid to be produced is introduced into the screen. 
     
     
         18 . The stirrer according to  claim 5 , wherein diameters of the blade and of the screen are decreased as departing in an axial direction from an introduction port through which the fluid to be produced is introduced into the screen. 
     
     
         19 . The stirrer according to  claim 2 , wherein
 the plurality of the slits has the same width in the circumferential direction and are formed with an equal distance in the circumferential direction, and   the screen does not rotate.   
     
     
         20 . The stirrer according to  claim 3 , wherein
 the plurality of the slits has the same width in the circumferential direction and are formed with an equal distance in the circumferential direction, and   the screen does not rotate.