US2735547A - vissac - Google Patents

Description

Feb. '21, 1956 G. A. VISSAC 2,735,547

CONE SEPARATOR Filed May '7, 1951 2 Sheets-Sheet l INVENTOR 60574 V5 ANDRE V/SSAC JMY ATTORNEYS G. A. VISSAC CONE SEPARATOR Feb. 21, 1956 2 sneets-snet 2 Filed May 7, 1951 C m & 7 7 f 5 6 0 W Z m 676 77 R a z i m m N WM. m 5 I m m 4 x fi W A P G I 9 I a 4 7 J a a ll \IIIIIIE United States Patent CONE SEPARATOR Gustave A. Vissac, Vancouver, British Columbia, Canada Application May 7, 1951, Serial No. 224,931

Claims. (Cl. %-211) This invention relates to cone separators in which particles are removed from fluids.

This apparatus may be used to separate materials from a fluid, such as water. It may be operated in much the same manner as an air cyclone to reclaim the materials from the fluid. The apparatus however may be used to advantage to separate maten'als of different specific gravities from each other, and from the fluid. For example, it may be used to separate fine coal pal? ticles from refuse, such as silica, shale and other impurities.

When the apparatus is used only as a clarifier or collector, the particles drop to the bottom and are periodically evacuated. However, when it is used to collect separately particles having different densities, it is necessary to provide additional differential forces capableof effecting the required separation.

The main part of this apparatus is constructed along the lines of an air cyclone. In order to separate particles of difierent densities, it is necessary to build up the tangential current of the cyclone feed at a proper value, maintaining proper agitation and building up the necessary suspension of particles to insure the required bath density. In addition to this, an upward current is introduced which is just strong enough to lift the particles of light density, but is too weak to support the particles of higher density so that the latter drop to the bottom of the device and are periodically evacuated.

This separating apparatus is divided into two sections,

an upper or cylindrical section, and a lower or conical section, the latter being in the form of an inverted cone. The upper section opens into the lower section. The specific gravities of the bath in these two sections are regulated in accordance with the materials to be separated. For example, in separating fine coal from other refuse it has been found advisable to use a medium density equal to 1.20 in this upper section, and a medium density equal to 1.36 at the top of this lower or cone section. For this purpose, test tubes are connected to the bottoms of the upper and lower sections. After the apparatus is filled with clean water, a certain air pressure is established in the test tubes, say for example, 3 pounds in the upper tube and 5 pounds in the lower tube. These pressures are indicated on gauges connected to the respective tubes. This corresponds to pure water of density 1.

When the fluid gravity in the upper section is built up to the desired point, say 1.20, it will be indicated by an increased pressure of 20% on the air gauge, namely, a reading of 3+.6 or 3.6 pounds.

In order to have a density of 1.36 at the top of the cone section, it has been found necessary to have a density of approximately 1.40 at the bottom of said cone, or an increase of 40% above the air pressure in the test tube, connected to said section. In this case, the reading on the gauge would be 5+2, or 7 pounds. With a feed of a controlled gravity, from a constant head tank, the control valves on the tangential and upward current feeds are set to maintain the desired densities in the upper and lower sections. The upward flow of fluid maintains particles in the upper section of the separator which would normally drop to the bottom of the cone section.

An example of the present invention is illustrated in the accompanying drawings, in which,

Figure 1 is an elevation of the cone separator and associated apparatus,

Figure 2 is a vertical section through the cone separator taken substantially on the line 2-2 of Figure 1 Figure 3 is a plan view of the apparatus, and

Figure 4 is a horizontal section taken substantially on the line 4-4 of Figure 1.

Referring to the drawings, the separator consists of a main or cylindrical section 10, and a lower section 11 in the form of an inverted cone. The main section has an entrance l5 lying substantially in a radial plane.

The best results are obtained when the wall 21 of the main section winds in a volute around and downwardly of the central axis of the cyclone, and extends from the outer side 22 of the entrance to the inner side 23 thereof. The upper edge 25 of the wall 21 slopes downwardly slightly from the point 22 to the point 23 on opposite sides of the entrance while the lower edge 27 of said wall extends downwardly betweenthese points at a much deeper angle, see Figure 1. A pipe 30 extends through the main section 10 from within the conical section ll and beyond the top of the main section. A cover 32 is shaped to fit over the top of the main section around this pipe.

The radius of the top 35 of the cone section is approximately equal to the radius between the hypothetical center 36 of the pipe 30, see Figure4, and the point 23. The space between the lower edge 27 of the main section wall and the top of the conical section is filled in by a suitably shaped piece of materials37. The wall of the cone section should be approximately'between 7 and 10 degrees to the vertical. In other words, the angle 41) between the cone wall and the vertical line 41, see Figure 1, should be within the range of 7 to 10 degrees.

A float chamber 44 is mounted on top of the cover 32 and communicates with the main section 10. A pipe 45 communicates with the top of this chamber, and has a control valve 46 therein. A pipe 4. 7 extends from this valve to a point of discharge, not shown.

A pipe 5% extends from the lower end of the cone section to a gate valve 51. Another pipe 54 extends from this valve to a refuse chamber 55. This chamber consists of two conical sections 56 and 57 joined together at their bases 58. A pipe 59 extends from the bottom of the chamber to a valve 6i) similar to valve 51. These valves can be set to control the refuse evacuation. A suitable screw conveyor 61, or a rotating valve, is positioned to receive material passing through valve 6th. A diffuser 62 is mounted in the cone section 11 adjacent but spaced above the lower end thereof by suitable mounting means, such as straps 63. The diffuser is in the form of a bowl-shaped circular baffle, the rim of which is spaced slightly from the cone Wall. 'A central cone 64 projects upwardly from the diffuser in line with and spaced from the lower end of pipe 30. The purpose of this diffuser is to convert the downward currents issued from pipe 30 into a uniform upward current directed towards the float chamber 44.

A reducer 65 extends outwardly from the entrance 15 of the section 113 down to pipe 66 having a control valve 67 therein, said pipe being connected to a relatively large cross fitting 68. A feed pipe 70 is connected to this fitting directly across from the pipe 66. The pipe 70is-connected to a suitable feed source for the slurry to ;be' sepa-- rated and cleaned. The feed pipe may be connected directly to a pump capable of delivering the slurry at the desired volume and speed, but it is preferable to have the pipe extend up to a head tank 71 into which the slurry is fed by a pipe 72 extending from a pump, not shown, under a constant head. The specific gravity of the fluid in this tank is controlled by pumping water into it at such a rate as to maintain a predetermined density.

A pipe 75 of relatively small diameter having a control valve 76 therein extends upwardly from the fitting 6E; and is connected to the pipe 30 above the chamber 44 at 77. A by-pass pipe 79 is connected to the outer end of the pipe 30 and has a control valve 80 therein.

A pipe 84 extends downwardly from the fitting 63 and opens into the refuse chamber 55, said pipe having a control valve 85 therein.

Suitable means is provided for controllings and registering in a relative manner the specific gravity of the solid-liquid solution within the refuse chamber 55 of the separator. This may be accomplished by a fairly large test tube 90 which communicates at one end with the refuse chamber. The opposite end of the test tube is closed by a cover 94, and an air pipe 95 extends from this cover to a gauge 96. Air is supplied to the pipe 95 by another pipe 96a extending from a suitable source of supply, not shown, through a pipe 97 having a reducing valve 98, air gauge 99 and control valve 100 therein.

The specific gravity of the fluid in the main section of the separator is controlled and indicated in a relative manner in the same way as in the refuse chamber. For this purpose, a fairly large test tube 105 extends through the cover 32 down into the main section. The opposite end of this tube is closed by a cover 106 and is connected by an air pipe 107 to a gauge 108. Air from the pipe 96a is directed to the pipe 107 through a pipe 110. The latter pipe has a reducing valve 111, air gauge 112 and control valve 113 therein.

To start up the apparatus, valves 76, 85, 46 and 60 are closed, and valves 67 and 80 are open. At this time, clear water is pumped into the head tank 71. This water flows through the pipes 70 and 66, and reducer 65 through the entrance into the main section 10 filling the entire apparatus and running out through pipes and 79. The reducing valves 98 and 111 are open to maintain the air pressure measured by gauges 99 and 112 at a certain point, say for example, 3 pounds. The control valves 100 and 113 are open so that the desired air pressure is maintained in the test tubes 90 and 105. The fluid containing particles to be separated is now pumped into the head tank. The specific gravity of the fluid in the section 10 is allowed to build up to a predetermined point by gradually opening valve 76. When this is done, fluid passes down through pipe 30 and is directed upwardly in conical section 11, thereby maintaining in suspension particles which otherwise would settle down in said section.

After valve 76 is closed, the apparatus may be used to separate particles entrained in the fluid in somewhat the same manner as in the air cyclone described and illustrated in the applicants co-pending United States patent application. Serial Number 218,870, now abandoned. When the slurry to be separated is being pumped into the head tank 71,- the slurry is directed into the main section 10 through the entrance 15. The volute wall 21 of this section directs the fluid downwardly and inwardly in a continuously tightening spiral flow so that the comparatively heavy particles in it are thrown against the wall by centrifugal force, and slide down by gravity along the cone wall and through the outlet pipe 50 into the chamber 55. The water with the remaining particles directed by the volute in a descending spiral comes in contact with the difiuser 62 and is thrown up and out through pipe 79, controlled by valve 80. In this way 4 Y the cyclone operates on the basic principles covered by the above-mentioned application S. N. 218,870, and acts as a particularly elficient solid thickener and water clarifier.

However, if and when a separation between the solids in suspension is required, the cone will be operated as follows:

Valves 76 and 46 are opened, and valve closed, to substitute a downward flow for the upward How in pipe 30. The operation of the diffuser 62 is then reversed, and the down flow from pipe 30 is directed upwardly through chamber 44, pipe 45 and valve 46, entrainingwith it the surplus fluid from the tangential feed 65.

The valve 76 is used to control the upward flow of fluid in chamber 10 to retain some of the heavy particles therein which would otherwise settle to the bottom of the device, thus building up a bath of a required density in this chamber. The spiral current adjusted by valve 67, insures proper agitation to maintain a stable suspension of the medium and light particles, and acts as a thickener of the heavier particles, as explained above.

The test tube 105 registers the gravity of the bath in chamber 10, and when the desired values have been built up, they are maintained by proper adjustment of the respective valves.

Having built and maintained the required bath density in chamber 10, automatically, under the influence of the upward current and the buoyancy created by the bath density, all particles of a certain size and density together with smaller particles of greater density will float up to chamber 44 to be evacuated by pipe 45. The heavy particles and the excess of the medium gravity particles will sink to the bottom of cone 11, and will be concentrated in the refuse chamber 55.

During operation, the heavier particles are thrown against the wall of the cylindrical section by centrifugal force in the inward spiral flow of the fluid, and these particles slide down the wall to the bottom of the inverted cone section. The medium particles directed by the volute wall of the upper section follow a narrowing spiral path down the centre of the cone to the difluser which directs them upwardly with the water from pipe 30 back into the upper section. The diffuser also spreads the upward flow of fluid towards the base of the float chamber 44 so that more particles are directed thereto than would be the case if the flow was not so diffused. The diffuser is so close to the cone wall that only the largest and heaviest particles pass therebetween, and it directs water upwardly to catch the largest particles of lower specific gravity and small particles of high specific gravity. The upward current lifts the large high specific gravity particles and allows the others to drop. Consequently, all large and medium size high specific gravity particles drop to the bottom of the cone section and all large and medium size lower specific gravity particles rise and are carried out of the device.

The gauge 96 of test tube registers the gravity of the concentrated solution in the refuse chamber. The gravity of this bath can be built up almost to the actual gravity of separation required, and accordingly any large coal particles, not picked up in chamber 10, will keep on floating until they are picked up at the diffuser 62.

It should be noted that a static bath is maintained in chamber 55, and, accordingly, it is possible to build up an actual density of from 1.35 to 1.45 as desired, but in chamber 10, in order to maintain the necessary fluidity, it is not possible to build a bath density over 1.20 or 1.25. As a consequence, the actual separation obtained will be limited by the law of equivalence; fine particles of refuse will be floated and discharged along with the large particles of coal. As a consequence, the products discharged through pipe 45, valve 46 and pipe 47 are delivered to a dewatering screen whose openings correspond to the size equivalence. V

For example if it is desired to clean particle sizes from 1 mm. to 0, the separation obtained by the above operation will be satisfactory only down to the size /1 mm. Accordingly, the openings of the dewatering screens will be mm. The resultant non-cleaned fraction will then be fed to another series of cone separators working on the same principle, and on such a small remaining size range these may be adjusted to give a satisfactory separation to complete the required operation.

Automatic registering or control of the densities can be obtained by setting various instruments on test tubes 90 and 105. One simple set-up is illustrated in Figure 1.

The tops of test tubes 105 and 90 are connected by tubing 95 and 107 to air gauges 96 and 108, and to a source of compressed air 96a through a system of reducing valves 98 and 111, followed by air gauges 99 and 112, and valves 100 and 113. These make it possible to build an original positive pressure corresponding to the unit density, to measure the increased densities as they are built up, and to signal or act when the final required densities are reached.

When it is desired to evacuate the refuse from the chamber 55, the screw conveyor 61 is set into operation either manually of automatically by apparatus not shown. If desired, the gauge 96 may be wired to act as a switch in an electrical circuit for starting a motor when the density in the refuse chamber reaches a predetermined point to turn the screw conveyor and evacuate a determined amount of refuse.

The pipe 84, controlled by valve 85, is for the purpose of creating a slight leakage of water down to refuse chamber 55 in order to compensate for the outflow of refuse, when ejected at the bottom, through pipe 59 and valve 60.

What I claim as my invention is:

l. A cone separator comprising an upper cylindrical section, a lower section in the form of an inverted cone communicating with the bottom of the upper section, a valve-controlled outlet at the bottom of the cone section, an entrance for the upper section through which a fluid containing particles may be directed, means for directing fluid and particles from the entrance downwardly and inwardly in a continuously tightening spiral flow, a fluid outlet at the top of the upper section, and means directing a flow of fluid upwardly through the lower section near the wall thereof and through the upper section to retain suspended therein some particles which would normally drop to the bottom of the cone section to maintain the density of the fluid at a predetermined point, a closed test tube communicating with the bottom of the upper section, into which fluid from the latter flows, means for maintaining a desired air pressure in the tube, and an air gauge connected to the tube for registering the pressure therein to indicate relatively the density of the fluid in the upper section. 2. A cone separator comprising an upper cylindrical section, a lower section in the form of an inverted cone communicating with the bottom of the upper section, a valve-controlled outlet at the bottom of the cone section, an entrance for the upper section, means for directing a fluid containing particles from a source to the section entrance, means for directing fluid and particles from the entrance downwardly and inwardly in a continuously tightening spiral flow, a fluid outlet at the top of the upper section, a pipe connected to the means for directing fluid with particles to the entrance and opening downwardly in the lower section centrally thereof through which some of the fluid containing particles may be discharged into said section, and means for directing the fluid and particles from the pipe upwardly through the upper section centrally thereof.

3. A cone separator comprising an upper cylindrical section, a lower section in the form of an inverted cone communicating with the bottom of the upper section, a valve-controlled outlet at the bottom of the cone section, an entrance for the upper section, means for directing a fluid containing particles from a source to the section en- 6 trance, means for directing fluid and particles from the entrance downwardly and inwardly in a continuously tightening spiral flow, a fluid outlet at the top of the upper section, a pipe connected to the means for directing fluid and particles to the entrance and opening downwardly in the lower section centrally thereof through which some of the fluid containing particles may be discharged into said section, a valve for controlling the flow in the pipe, and a diffuser in the form of a bowl-shaped circular batfle mounted in the lower section spaced slightly from the wall thereof immediately below the discharge end of the pipe for directing the fluid and particles therefrom upwardly through the lower section near the wall thereof and through the upper section.

4. A cone separator as claimed in claim 3 in which the diffuser has a central cone projecting upwardly therefrom in line with and spaced from the discharge end of the pipe.

5. A cone separator comprising an upper cylindrical section, a lower section in the form of an inverted cone communicating with the bottom of the upper section, a refuse chamber connected to the bottom of the lower section, said chamber being much larger transversely than the bottom of the cone section, an entrance for the upper section through which a fluid containing particles may be directed, means for directing fluid and particles from the entrance downwardly and inwardly in a continuously tightening spiral flow, a fluid outlet from the upper section, means in and connected to the separator for setting and maintaining at a predetermined point the density of the fluid in the upper section, and means connected to the bottom of the refuse chamber periodically evacuating said chamber.

6. A cone separator as claimed in claim 5 including valves between the conical section and the refuse chamber and between the latter and the evacuating means.

7. A cone separator comprising an upper cylindrical section, a lower section in the form of an inverted cone communicating with the bottom of the upper section, a refuse chamber connected to the bottom of the lower section, said chamber being much larger transversely than the bottom of the cone section, an entrance for the upper section through which a fluid containing particles may be directed, means for directing fluid and particles from the entrance downwardly and inwardly in a continuously tightening spiral flow, a fluid outlet at the top of the upper section, means directing a flow of fluid upwardly through lower section near the wall thereof and through the upper section to maintain the density of the fluid at a predetermined point to retain suspended therein some particles which would normally drop to the bottom of the cone section and means connected to the bottom of the refuse chamber periodically evacuating said chamber.

8. A cone separator as claimed in claim 7 including a closed test tube communicating with the refuse chamber into which fluid from the latter flows, means for maintaining a desired air pressure in the tube, and an air gauge connected to the tube for registering the pressure therein to indicate relatively the density of the fluid in the chamber.

9. A cone separator comprising an upper section having an entrance lying substantially in a radial plane, the wall of said section being in the form of a volute extending from the outer side of the entrance to the inner side thereof and extending downwardly relative to the central axis of the separator, a lower section in the form of an inverted cone communicating with the bottom of the upper section, means for directing a particle-laden fluid of constant density through the entrance to create a downward and continuously tightening spiral flow in the section, said fluid and particles following a narrowing spiral path downwardly and centrally of the lower section, a pipe connected to a fluid source opening downwardly in the lower section centrally thereof through which a fluid may be discharged into said section, and means for continuously directing the fluid from the pipe upwardly through the upper section near the wall and centrally thereof. 7

' 1 0. A cone separator comprising an upper cylindrical section, a lower section in the form of an inverted cone communicating with the bottom of the upper section, a refuse chamber connected to the bottom of the lower section, said chamber being much larger transversely than the bottom of the cone section, an entrance for the upper section through which a fluid containing particles may be directed, means for directing fluid and particles from the entrance downwardly and inwardly in a continuously tightening spiral flow, a fluid outlet at the top of the upper section, means directing a flow of fluid upwardly through the lower section near the wall thereof and through the upper section to retain suspended therein some particles which would normally drop to the bottom of the cone section to maintain the density of the fluid at a predetermined point, means for supplying fluid to the refuse chamber to regulate the density of the fluid therein, and means connected to the bottom of the refuse chamber for periodically evacuating said chamber.

11. A cone separator comprising an upper cylindrical section, a lower section in the form of an inverted cone communicating with the bottom of the upper section, a refuse chamber connected to the bottom of the lower section, said chamber being much larger transversely than the bottom of the cone section, an entrance for the upper section, means for directing a fluid containing particles through the entrance, means for directing fluid and particles from the entrance downwardly and inwardly in a continuously tightening spiral flow, a pipe connected to the means for directing fluid and particles to the entrance and opening downwardly in the lower section centrally thereof through which some of the fluid containing particles may be discharged into said section, a valve for controlling the flow in the pipe, a diffuser in the form of a bowl-shaped circular batfle mounted in the lower section spaced slightly from the wall thereof immediately below the discharge end of the pipe for directing the fluid and particles therefrom upwardly through the lower section near the wall thereof and through the upper section.

12. A method of separating particles of difierent specific gravity from each other and from a fluid which comprises directing a particle-laden fluid of substantially constant density downwardly in a narrowing spiral path in and centrally of a separator, directing a particle-laden fluid upwardly through the separator near the wall thereof to separate equivalent particles of different specific gravities, regulating the upward flow of fluid to maintain a bath of a predetermined density in the separator near the top thereof, removing fluid and particles from the top of the separator, and removing large heavy particles from the bottom of the separator.

13. A method of separating particles of different specific gravity from each other and from a fluid which comprises directing a particle-laden fluid of substantially constant density downwardly in a narrowing spiral path in and centrally of a separator which converges downwardly to an outlet, directing fluid upwardly through the separator near the wall thereof to separate equivalent particles of different specific gravities, regulating the upward flow of fluid to maintain a bath of a predetermined density in the separator near the top thereof, removing fluid and particles from the top of the separator, directing the large heavy particles from the bottom of the separator into a closed refuse chamber which is much larger transversely than the separator outlet, directing a flow of fluid to the refuse chamber to maintain a predetermined density therein, and removing the particles from the refuse chamber.

14. A method of separating particles of different specific gravity from each other and from a fluid which comprises directing a particle-laden fluid of substantially constant density downwardly in a narrowing spiral path in and centrally of a separator having an upper section and a lower section in the form of an inverted cone, directing a particleladen fluid upwardly through the lower section into the upper section near the wall and centrally thereof to separate equivalent particles of different specific gravities, regulating the upward flow of fluid to maintain a bath of a predetermined density in the upper section, removing fluid and particles from the top of the separator, and removing heavy particles from the bottom of the separator.

15. A cone separator comprising an upper section having an entrance lying substantially in a radial plane, the wall of said section being in the form of a volute extending from the outer side of the entrance to the inner side thereof and extending downwardly realtive to the central axis of the separator, a lower section in the form of an elongated inverted cone connected to the bottom of the upper section and extending downwardly therefrom, an outlet at the bottom of the cone section, means for directing a fluid laden with particles of different specific gravities through the entrance along the volute wall to create a V downward and continuously tightening spiral flow in the section, said fluid and particles following a narrowing spiral path downwardly and centrally of the lower section, a diffuser in the form of a bowl-shaped circular baflle mounted in the lower section well above the outlet thereof and spaced slightly from the section wall to prevent large particles of low specific gravity from passing therebetween, a pipe opening downwardly in the lower section centrally thereof immediately above the diffuser and connected to the means for directing fluid and particles to the entrance, said diffuser directing fluid and particles from the pipe upwardly near the wall and centrally of the cone section, a refuse chamber connected at its top to the cone section outlet, said chamber diverging to a width considerably greater than that of the lower section outlet and converging to an outlet at its own bottom, and a normally-closed valve controlling the refuse chamber outlet.

References Cited in the file of this patent UNITED STATES PATENTS 1,748,569 Hibbard Feb. 25, 1930: 2,008,643 Lockett July 16, 1935 2,104,537 Ellis Jan. 4, 1938 2,222,930 Arnold Nov. 26, 1940 2,537,904 McAllister Jan. 9, 1951 FOREIGN PATENTS 340,027 Great Britain Dec. 19, 1930 529,692 Great Britain Nov. 26, 1940

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