JPH04227836A - Method and device for mixing liquid and solid - Google Patents

Abstract

PURPOSE: To provide a method for mixing a liquid and solids and a device therefor. CONSTITUTION: In a method for mixing a liquid and solids, the solids are fed into the liquid whilst the liquid is swirling about the surface of a converging chamber 18. The chamber 18 is composed of at least two frusto-conical portions 20, 22 disposed one above the other. The upper portion 20 has a substantially larger included angle than that of the lower portion 22. Inlet nozzles 44 are supplied from an annular plenum 42 and are arranged tangentially with respect to the upper end of the chamber 18 so as to induce swirling of the liquid injected into the chamber 18. Mixed liquid and solids from the chamber 18 are arranged to discharge into a vessel having a vortex breaker at its outlet.

Description

[Detailed description of the invention]

The present invention relates to a method and apparatus for mixing liquids and solids, and more particularly, but not exclusively, to a method and apparatus for continuously mixing liquids and powdered solids. According to a first aspect of the invention, there is provided a method for mixing a liquid and a solid, which method comprises supplying a solid to a liquid swirling on the surface of a chamber tapering downwardly towards an outlet; consists of at least two frustoconical sections, one above the other, the upper section having an interior angle that is substantially greater than the interior angle of the lower section.

According to a second aspect of the present invention, the first aspect of the present invention
The method of the second aspect provides an apparatus for mixing a liquid and a solid, the apparatus comprising a chamber having a plurality of liquid inlets arranged at an upper end to induce swirling of the liquid and an outlet at a lower end; means for supplying solids to the upper end of the chamber, the chamber comprising at least two truncated conical sections, one above the other, said upper section having an internal angle substantially greater than an internal angle of said lower section. .

[0003] The liquid preferably flows turbulently in this region. It is desirable that the interior angle of this portion maintains the tangential component of the liquid flow above a predetermined velocity. In one form of the invention, the solid may have an average particle size of 5 to 500 μm, for example a micronized powder has an average particle size of 5 to 10 μm.

0004

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention will now be further described by way of example with reference to the accompanying drawings, in which: FIG. Referring to FIG. 1, a liquid/solid mixing apparatus 10 is shown, which consists of an inlet top assembly 12 and a collection vessel 14. A powder feed passage 16 is arranged so that the powder passes through the inlet upper assembly 12 and falls into the tapered chamber 18 . Tapered chamber 1 as shown more clearly in Figure 2
8 has an upper frusto-conical portion 20 joined to a lower frusto-conical portion 22 having an outlet 24 to the collection container 14 . An inlet 26 for liquids discharges into the inlet top assembly 12. Collection container 14 discharges through outlet 28 into line 30 which is connected to pump 32. The pump 32 has a branch line 3 for recirculating the liquid and solid mixture into the tapered chamber 18 when desired.
A product discharge pipe 34 having a diameter of 5 is provided.

Referring now to FIGS. 3 and 4 in more detail, the inlet top assembly 12 includes respective parallel circular flanges 36 having body members 40 therebetween defining a chamber 42 that defines an annular plenum from which the inlet 26 exits. 38. A plurality of nozzles 44 (10 as shown) from an annular plenum chamber 42 are aligned generally tangentially with respect to a cylindrical inlet chamber 46;
A plenum chamber 42 is connected to the entrance chamber. Upper part 20
connects to the flange 38 below the inlet chamber and connects the tube 4 from the powder supply channel 16 (not shown in FIGS. 2 and 3).
8 passes through the inlet chamber 46 to discharge into the upper part 20. At the outlet 28 of FIG. 1, a vortex disruptor 50 illustrated in FIG.
The vortex disruptor 50 includes a disk 52 having several holes 54 (three in the figure) for the passage of liquid flow.

In operation, liquid is discharged through inlet 26 into plenum chamber 42 and through nozzle 44 into inlet chamber 4 .
6, it is discharged at an angle to that point so as to cause a spiral motion. From the inlet chamber 46 the liquid falls into the upper part 20;
And because of the relatively large angle formed in the upper part 20, the downward liquid flow reduces the velocity, which causes the upper part 2
Ensure that the entire surface of the 0 is wetted with liquid. From the upper part 20 the swirling liquid falls into the lower part 22 and then, still swirling, falls through the outlet 24 into the collection container 14 . The powder supplied from the powder supply channel 16 and passed through the tube 48 falls onto the wetted surfaces of the upper section 20 and the lower section 22 where it is mixed with the liquid. The effect of the angular shape of the upper portion 20 and lower portion 22 is to overcome the effects of friction and maintain a tangential component of the liquid flow as it falls into the tapered chamber 18. Therefore, as the liquid falls into the container 14 within the tapered chamber 18, a swirling motion of the liquid is maintained. The mixed liquid/powder is then passed through outlet 28 and tube 30.
through the pump 32.

The velocity of the liquid flow is arranged to ensure that there are no dry areas in the upper portion 20 and lower portion 22 for powder to collect. The flow is also arranged to be turbulent within the tapered chamber 18 to promote dispersion of the powder by the liquid. A typical liquid flow rate of about 6.5 m/sec at a pressure of 3 x 105 N/m2 was achieved in the upper section 20.
constitutes an angle of 30 degrees from the vertical (i.e., an internal angle of 60 degrees) and the lower portion 22 constitutes an angle of 7 degrees to 10 degrees from the vertical (i.e., an internal angle of 14 degrees to 20 degrees). Met.

The liquid may be organic, eg an organic solvent, or an organic aqueous solution, eg an acid or alkaline aqueous solution. The powder may have an average particle size of between 5 and 500 μm, for example it may be a micronized powder with an average particle size of 5 to 10 μm. A first advantage of the present invention is that continuous mixing of liquid and solid occurs and the absence of dry areas at the mixing surface suppresses localized accumulation of solids. If necessary, the mixed liquid and solids can be recirculated through the apparatus through branch line 35. A common screw feeder device (not shown) can be used to feed powder into the powder feed path 16. Examples Example 1 Mixing of diatomaceous earth and water is as follows: a) @ 90 liters/hr = 18 kg/hr of powder feed 420 liters/hr of water b) 48 liters/hr of water except (a ) Same as c)
200 liters/hr = 40 kg/hr powder supply 42
Example 2 Same as (c) except 0 liter/hr water d) 195 liter/hr water Pharmaceutical powder a) 22-44 kg/hr basic pharmaceutical powder @ 120-24
0 liter/hr mixed organic solvent b) @22-44 kg
/hr basic pharmaceutical powder @ 170-340 liters/hr organic solvent Example 3 Fluff-like precipitate dispersion accelerator @ 0.3-1.2 kg/hr fine particles @ 195-390 liters/hr water Above implementation The example liquids and solids were successfully mixed using the apparatus of FIGS. 1-5.

[Brief explanation of the drawing]

FIG. 1 is a schematic illustration of an apparatus for mixing liquid and solid.

FIG. 2 is an enlarged partial view of FIG. 1;

FIG. 3 is an enlarged sectional view taken along line III-III in FIG. 1;

FIG. 4 is a sectional view taken along the line IV-IV in FIG. 3;

FIG. 5 is an enlarged partial view taken along line V-V in FIG. 1;

[Explanation of symbols]

10 Liquid/solid mixing device 16 Powder supply path 18 Tapered chamber 20, 22 truncated conical part 42 Plenum 44 Inlet nozzle

Claims (23)

[Claims] 1. A solid is supplied to a liquid swirling on the surface of a chamber (18) which tapers downwardly towards an outlet (24), the chamber (18) comprising at least one chamber (18) positioned one above the other. A method for mixing liquids and solids, characterized in that it consists of two frustoconical parts (20, 22), said upper part (20) having an internal angle that is significantly larger than the internal angle of said lower part (22). 2. A method according to claim 1, wherein the liquid flows turbulently through the sections (20, 22). 3. A method according to claim 1, wherein the internal angles of the sections (20, 22) are such that the tangential component of the liquid flow is maintained above a predetermined velocity. 4. The method of claim 3, wherein the liquid has a flow velocity of about 6.5 m/sec. 5. A method according to claim 3, wherein the liquid is discharged into the upper part (20) at a pressure of approximately 3×10 5 N/m 2 . 6. A method according to claim 3, wherein the solid comprises a powder having an average particle size of 5 to 500 μm. 7. A method according to claim 6, wherein the powder has an average particle size of 5 to 10 μm. 8. The method of claim 6, wherein the solid comprises diatomaceous earth or a fluffy precipitate dispersion promoter. 9. The method of claim 8, wherein the liquid comprises water. 10. Claim 1, wherein the solid comprises a pharmaceutical mixture.
8. The method according to any one of 7. Claim 11: Claim 10, wherein the liquid is an organic liquid.
The method described in. 12. The method of claim 11, wherein the organic liquid has a flow rate of 170 to 340 liters/hr. 13. The mixed liquid and solids from the outlet (24) are recycled through the chamber (18).
2. The method according to any one of 2. 14. A plurality of liquid inlets (44) aligned at the upper end to cause swirling of the liquid and an outlet (44) at the lower end.
24) and means (16, 48) for supplying solids to the upper end of the chamber (18), the chamber (18) having at least two truncated ends arranged one above the other. 2. Mixing a liquid and a solid according to claim 1, characterized in that the method comprises conical parts (20, 22), the upper part (20) having an internal angle that is significantly larger than the internal angle of the lower part (22). equipment for. 15. Apparatus according to claim 14, wherein the inlet (44) is arranged to be fed from an annular plenum (42) arranged around the chamber (18). 16. Apparatus according to claim 14 or 15, wherein the outlet (24) is connectable to the inlet of a container (14) for collecting the solid and liquid mixed in the chamber (18). 17. The means (50) for disrupting the vortex is arranged in a container (
17. The device according to claim 16, arranged at the outlet (28) from 14). 18. Apparatus according to any of claims 14 to 17, wherein the means (48) for supplying solids extend below the inlet (44) and terminate above the upper part (20). 19. A device according to claim 14, wherein the upper part (20) has an internal angle of approximately 60 degrees. Claim 20: The lower portion (22) has an angle of 14 degrees to 20 degrees.
20. A device according to any of claims 14 to 19, having an internal angle of degrees. 21. The inlet (44) is located at the upper end (
21. A device according to any one of claims 14 to 20, wherein the device is aligned substantially tangent to 46). [Claim 22] A container (14) for storing the mixed liquid and solid.
Pumping means (32) connects the container outlet (28) to
22. The device according to any one of claims 14 to 21, wherein the device is connectable to a device. 23. The pump means (32) is arranged to discharge through the discharge duct means (34) and the branch duct means (35) pump the mixed liquid and solids into the chamber (18).
23. Apparatus according to claim 22, connectable to exhaust duct means (34) for recirculating to.