US1987724A - Colloid mill - Google Patents

Description

Patented Jan. 15, 1935 UNITED ISTATES COLLOID MILL Charles P. Tolman, Kew Gardens, N. Y., assignor, l

by mesne assignments, to The Noble &` Wood Machine Co., Hoosick Falls, N. Y., a corporation of New York Application November 8, 1930, Serial No. 494,252

3 Claims.

The present invention relates to an improvement in colloid mills. One object thereof has been to provide a colloid mill whereby the treated or completed product can be separated automatically and continuously from the uncompleted or partly treated product and whereby said partly treated product may be returned to the mill or retained therein for further treatment or until it reaches the completed state or condition.

In present colloid mill practice, itis not unusual for a product which appears to be in effective and permanent dispersion to show extensive sedimentation after standing for a time. Furthermore, where, in the course of treatment in a colloid mill, undispersed or unreduced particles are enveloped in a mass of dispersed or reduced particles, the shearing' forces are somewhat cushioned or nullied thus diminishing the shearing or dispersing` effect upon the unreduced or undispersed particles. According to my invention, I preferably separate the unreduced particles from thosev which are of celloidal fineness as soon as may be after the latter are formed so that the full shearing force of the mill may be directly employed upon the unreduced particles.

My invention is illustrated in the embodiments thereof described in the present specification and shown in the accompanying drawing, inwhich Figure 1 is a central longitudinal section of one form;

Figure 2,`a central longitudinal section of a modified form; and f Figure 3, a diagrammatic representation of a plurality of connectedcolloid mills arranged in such a way that the finished product is continuously removed while the unnished product is segregated and advanced to another mill or other mills for further treatment or until it reaches the nished state.

`Referring to the drawing, a colloid mill according to my invention includes the usual or special cooperating surfaces arranged to effect hydraulic shear and means for separating relatively reduced or dispersed particles of product from portions thereof which are unreduced or undispersed and continuing the treatment of said unreduced portions while the reduced or dispersed portions are permitted to be removed. As indicated in Figure 1, one form of apparatusfor this purpose includes a casing or stator l having a valve controlled inlet 2, the interior surface of said casing being of truncated conical contour and provided with annular grooves 3, 4, 5 and 6. A rotor 7 mounted on shaft 8 is adjustable relatively to the interior surface off'stator 1 by any suitable adjusting means 9. 10 communicates with groove 3 and is controlled by means of a valve 11. A discharge pipe 12 communicates with groove 4 and is connected by means of a pipe 13 with a discharge pipe 14 com- A discharge pipe municating wthgroove 5. A valve 15 controls the discharge pipe 12 and a valve 16 is placed in the connecting pipe 13. The groove 6 is discharged through a pipe 17 provided with a control valve 18.

It will be noted in connection with Figure 1 that the rotor 7'is in effect a hollow truncated cone having the outer edge of its open end beveled at 19. Another member, here shown as a second rotor 20 mounted ony shaft 21 cooperates with the interior surface of rotor 7 and is yadjustable with respect thereto `by means of any suitable adjusting device, as 22. The outer end of rotor 20 is beveled'at 23 to form an annular channel between said rotor and the edge of the open end of rotor 7. Shaft 21 also carries a plurality of paddles or blades 24 positioned and adapted to produce a. centrifuging effect in the space between the outer end of rotor 20 and the adjacent end of casing l. The rotor 7 is provided with a plurality of outlet ports 25 communicating with thev groove 5.

In operation, relative movement between rotor 7 and the casing or stator l is effected simultaneously with relative movement between rotor 7 and rotor 20, said rotors being rotated either in opposite directions or in the'same direction at different speeds, or as desired. In some cases, it may be advantageous to arrest rotation yof rotor 20 and actuate only the rotor 7. However, to produce a centrifuging effect, rotor 20 is actuated and causes the heavier or larger particles of the material fed into the inlet chamber through the pipe 2 to be moved outwardly into the groove 3. The lighter or smaller particles are caught in the annular channel between the bevel 23 and the adjacent inner edge of rotor '1. 'Ihe apparatus will preferably be set to separate the particles of material on the basis of their readiness for quick dispersion or modification into colloidal condition. The particles not properly or completely prepared may be discharged through pipe l0 for further preliminary treatment if desired. The remaining finer orI lighter material is subjected to shearing action between the inner surface of rotor 7 and the outer surface of rotor 20 and is dis- Icharged through ports 25, groove 5 and pipe 14 if desired. Such of the heavier material as moves down between stator l' and rotor 20 will be accumulated 4in groove 4 and may be discharged therefrom through pipe 12. The remainder will continue downwardly and out through the groove 5 and discharge pipe 14, or it may discharge through groove 6 and outlet 17.

When valve l1 is opened, thus permitting the heavier particles to be withdrawn from the apparatus, the device works as a centrifuge separator, retaining only the finer or lighter particles. When valve 11 is closed the beaver particles are forced downwardly between casing 1 and the rotor 'I and' subjected to normal shearing action and may be withdrawn as above described. By closing valve 15 and valve 16 they may be subjected to further shearing action until they reach the groove or the groove 6 as desired. In this way, the device operates as a combined centrifuge separator and colloid mill with the dispersing and separating action taking place simultaneously and in a continuous operation.

Referring now to Figure 2, a hollow truncated conical rotor 30 is mounted on shaft 31 to rotate within a casing or stator 32, the interior surface thereof being provided with annular grooves or recesses 33, 34, 35 and 36. An outlet pipe 37 controlled by a valve 38 communicates with the recess 33. An outlet pipe 39 controlled by a valve 40 communicates with recess 34. An outlet pipe 41 controlled by valve 42 communicates with recess 35. An outlet pipe 43 controlled by a valve 44 communicates with recess 36. The rotor 30 is provided with a plurality of ports 45 communicating with recess 35.

Another rotor 46 mounted on a shaft 47 has a portion of its exterior truncated conical surface arranged in lm shearing relation to a portion of the interior conical surface of the casing or stator 32. Another portion of the truncated conical surface of rotor 46 is in lm shearing relation to a portion of the interior truncated conical surface of rotor 30 which is open at one end to receive said portion of the rotor 46. In a preferred form of apparatus, the open end edge of rotor 30 presents a beveled surface 60 outwardly towards groove 33 and also aV beveled surface 61 inwardly towards rotor 46 which is itself tapered at 62 opposite said interiorly disposed bevel to form an annular channel between the upper edge of the rotor 30 and the tapered portion of rotor 46.

Material is supplied to the apparatus for treatment through an inlet pipe 48 controlled by a valve 49 and communicating with an annular recess or groove 50. The rotor 46 is provided intermediate its ends with an annular groove 51 within which are disposed a plurality of radially arranged paddles or blades 52 with their outer edges exposed toward the groove 33 in casing 32.

In operation, material to be treated is fed into groove 50 through pipe 48 and is given a combined longitudinal and rotational movement between rotor 46 'and the interior surface of casing 32. Upon reaching the position of paddles 52 in groove 51, the heavier particles are thrown outwardly toward groove 33 while the lighter particles work downwardly between the outer surface of rotor' 46 and theinner 'surface of rotor 30. Further reducing treatment may be accorded to the heavier particles if valve 38 in pipe 37 is closed. Otherwise, the heavier particles may be withdrawn or discharged from the apparatus. The lighter particles' in eithercase are further subjected to shearing action as above described. 1f valve 38 is closed,l the heavier particles are subjected to shearing action between the inner surface of casing 32 and the outer surface of rotor 30 and may be discharged at groove 34 through pipe 39 if desired. If this pipe is closed by means of valves 40 and 42, the material may be again subjected to further shearing action in that portion of the apparatus between grooves 34 and 35, and discharged from the latter through pipe 41. If pipe 41 is closed by valve 40, the discharge from groove 35 will proceed through to groove 36 to be discharged through pipe 43.

in Figure 1 wherein an initial separating actionV takes place as soon as the material comes in contact with the blades or paddles 24.

In the arrangement shown in Figure. 3, material to be treated is fed into a combined centrifuge and colloid mill, having centrifuging means, such for example asthose hereinabove described, if desired. 'I'he finished product is withdrawn from the rst mill 5,1 through pipe 52 while the unfinished product discharges from said first mill.

through pipe 53 into a second mill 54. 'I'he finished product from 54 discharges through 55 while the unfinished product discharges through 56 into a third mill 5'?, all of said products finally reaching a suitable container or collecting tank, as 58. It is contemplated that the partially treated or finished material may be re-treated in the same or different mills as often as desired or necessary to produce the finished product, while such product as is properly finished is continuously withdrawn from each mill as it is formed. With this arrangement and mode of operation, the time and energy of treatment is not wasted upon products which have been finished or completed in a relatively short time, thus aiIording a measure of economy which is not possible with mills of known types in the prior art which present only a single path over which the entire product must be moved regardless of the fact that large portions thereof are completed after relatively short periods of treatment.

I claim as my invention:

1. In a colloid mill, the combination of ,a stator member having an interiorly exposed recess and an outlet conduit communicating with said recess, a rotor member in spaced nlm shearing relation to interior portions of said stator and overlapping a portion of said exposed recess, a third member having portions in spaced film shearing relation` to said rotor member, and means for moving parts of the material being treated into said exposed recess and other parts of said material into position for shearing action between said rotor and said third member.

2. In a colloid mill, the combination of a hollow stator having an inlet opening, a rotor having a portion of its surface in film shearing relation to an interior surface of said stator, centrifuging means mounted on said rotor, and a second rotor having a nlm shearing surface in operative relation to an interior surface of 'said rst mentioned rotor and positioned to exert ef- -fective film shear in respect toa portion of the material acted upon by said centrifuging means. 3. In a colloid mill the combination of three concentrically-arranged film shear producing members including a stator and two rotors, one of said rotors having a portion interposed in film-shearing relation between said stator and said other rotor to form therewith respectively an outer and an inner shearing gap, and said other rotor being provided with centrifuging means operatively arranged in relation to the inlet ends of said shearing gaps whereby heavier particles of the material treated enter said outer gap and lighter particles enter said inner gap. CHARIES P. TOLMAN.

Images