US2671560A - Multiple hydrocyclones - Google Patents

Description

March 1954 F. J. FONTEIN ET AL MULTIPLE-HYDROCYCLONES 5 Sheets-Sheet 1 Filed June 14, 1950 FIG! INVENT Freerk J. Fon mm Jan N. Leemm QAflLMMM ATTORNEY 1954 F. J. FONTEIN ETAL 2,671,560

MULTIPLE-HYDROCYCLONES 5 Sheecls-Sheet 2 I Filed June 14, 1950 FIG. 2

FIG. 3

INVENTORS Freerm J. Fomein Jun J. Leeman TORN r h 9, 1954 F. J. FONTEIN ETAL MULTIPLE-HYDROCYCLONES 5 Sheets-Sheet 3 Filed June 14, 1950 INVENTORS Freerk J. Fontein Jan N. J. Leemun BY M... nvld mw ATTORNEY March 1954 F. J. FONTEIN ETAL 2, 56

MULTIPLE-HYDROCYCLONES Filed Jurie 14, 1950 5 Sheets-Sheet 4 INVENTORS Freerk J. Fontein Jan N. J. Leemun QJJQMW mam ATTORNEY March 9, 1954 Filed June 14, 1950 F. J. FONTEIN ETAL MULTIPLE-HYDROCYCLONES 5 Sheets-Sheet 5 'INVENTOR s Fmevk J. Fmm Jan N. J. Lwm

ATTORNEY Patented Mar. 9, 1954 MULTIPLE HYDROCYCLONES Freerk J. Fontein, Heerlen, and J an N. J. Leeman,

Hoensbroek, Netherlands, assignors to Stamicarbon N. V., Heerlen, Netherlands Application June 14, 1950, Serial No. 168,132

14 Claims.

This invention relates to hydrocyclones such as are used to treat solids in liquid suspension for the purpose of thickening or of classifying the suspended solids into predetermined fractions. Such solids may be either organic or inorganic, such as starch, paper-pulp, ores, coal, phosphate rock, and the like. However, such diverse materials require different dimensions of hydrocy clones and different operating conditions, so a brief description of the general characteristics of such a hydrocyclone may be helpful.

A hydrocyclone is a generally cylindrical vessel comprising a truly cylindrical part or section which merges into a generally conical part or section. There is an opening at the apex of the cone of the conical section and there is another opening, coaxial with the apex opening, in the cover-plate on the cylindrical section.

In the opening in the cover-plate, is carried a tube that extends from that plate outward and extends inwardly into the cylindrical section of the hydrocyclone. This is called a vortex finder. There is a tangential feed inlet to the cylindrical section. I

In operation, the liquid suspension is supplied to the hydrocyclone under pressure through the tangential feed. inlet to the cylindrical section whereby the suspension is given a quick enough rotational impulse to keep it rotating during its passage through the hydrocyclone. One fraction of the suspended solids is discharged from the hydrocyclone through the apex opening while another fraction is discharged through the vortex finder and thus from the base of the generally conical hydrocyclone. The apex-discharge contains the larger suspended solids while the basedischarge contains the smaller suspended solids, if separation is being based upon sizedifference. If separation is based upon specific gravity difference, the solids having less specific gravity are discharged through the base, while the solids having greater specific gravity are discharged through the apex. As separation in a hydrocyclone is dependent upon intense rotational forces, no obstructions can be tolerated in the hydrocyclone which must have a perfectly smooth bore for otherwise harmful secondary eddies are set up. The feed entrance also must be smooth and unobstructed.

The functioning of a hydrocyclone is readily effected by slight environmental changes, such as changing the area of the infeed entrance; the infeed pressure; the diameter of the apex-discharge; the diameter of the length of the vortex finder; the diameter of the length of the cylindrical section; or the shape of the conical section. In general, the smaller the dimension of the suspended solids to be separated, the smaller must be the diameter of the cylindrical section of the hydrocyclone. For instance, a hydrocyclone for the separation of phosphate rock from limestone will have a cylindrical section of the order of 48 inches in diameter, whereas a hydrocyclone for the thickening of starch will have a cylindrical section of the order of one-half an inch in diameter. A 48-inch hydrocyclone will have an hourly capacity of about 10,000 times that of a halfinch hydrocyclonethe capacity of the latter being about 25 gallons per hour.

Thus, in a starch factory where it is desired to thicken say 25,000 gallons of starch per hour, 1,000 half-inch hydrocyclones would be required. While this may seem to be a startling number, the efficiency of these smaller hydrocyclones for making satisfactory separations along the line of infinitesimal size differences, is such as to make their use desirable. However, mechanical problems of hooking up so many tiny hydrocyclones as to feed, and discharges, are serious. So it is a major object of this invention to take this tiny type of hydrocyclone out of the laboratory stage by devising ways and means whereby they are to be supplied and discharged economically without having a maze of feed and discharge pipes and fittings.

A further object of this invention is to devise ways and means to collect a considerable number of hydrocyclones in a small space. Another object of the invention is to devise ways and means whereby a multiplicity of hydrocyclones, hereinafter referred to as a multiple-hydrocyclone, can be cast or moulded into a unit which can be housed in a single casing or container.

A more specific object of the invention is to cast or mould the conical and cylindrical section and the infeed entrance thereinto of every hydrocyclone in the multiple-hydrocyclone into a block-like body unit, while casting or moulding separate cover-plates provided with vortex-finders to cover the hydrocyclones of the multiplehydrocyclone. Another object of the invention is to devise ways and means to exert forces from every direction on a multiple-hydrocyclone in operation, so that such multiple-hydrocyclone even when it is composed of resilient material like soft rubber, will retain its original shape in operation.

, In other words it is an object of this invention to secure together a soft rubber body block and a multiplicity of cover-plates in a main body assembly to which can be applied a minimum of other separable sections that contain within themselves the essential feed and discharge openings required to make the multiple-hydrocyclone into an operable device with no external accessories other than a unitary feed conduit and a unitary conduit each for the base-discharges and for the apex-discharges. A further object of the invention is to devise ways and means whereby the discharge of one multiple-hydrocyclone can be fed into and treated in another multiplehydrocyclone which is housed in an extension of the casing housing the first mentioned multiplehydrocyclone.

To realize these objects, the invention comprises a construction consisting of a substantially cylindrical body block, cover-plates and a casing to secure these parts together, this construction containing at least as many hydrocyclones as there are cover-plates in the construction, an infeed entrance for every hydrocyclone and a substantially central hole connected directly or indirectly with the infeed entrances. The central hole is connected with an infeed tube. The vortex-finders of the hydrocyclones of a multiple-hydrocyclone discharge into on common vessel, whereas the apex-apertures discharge into another common vessel. The construction is provided with means to disconnect the infeed means and the separate discharge means of one multiple-hydrocyclone, although a discharge vessel of one multiple-hydrocyclon may b connected with the central hole of another multiplehydrocyclone.

The best embodiment of. the invention now known to us will be described hereinafter for illustrative purposes but it is to be understood that it is illustrative and not limiting because obviously certain changes and modifications are possible as long as they fall within the metes and bounds as defined by the appended claims or the equivalents of the latters requirements.

In, the accompanying. drawings the embodiment has been illustrated wherein:

Figure 1 is. a perspective view of. a multiplehydrocyclone partially provided with coverplates and partially broken away;

Figure 2 is a longitudinal section of the multiple-hydrocyclone;

Figure 3 is a cross-section of the multiplev hydrocyclone;

Figure. 4 is a plan view of the multiple-hydrocyclone partially provided with cover-plates;

Figure 5 is a longitudinal section of an assembly with two multiple-hydrocyclones in series;

Figure 6 is a plan view of the assembly of Figure 5;

Figure '7 is a longitudinal section of an assembly with two multiple-hydrocyclones in parallel.

The, cylindrical body block. or multiple-hydrocyclone I is shown in the Figures 1 to 4 inclusive. A central cylindrical infeed hole 2 extends from one end to the other end of block I so that the block I has an annular shape. Three radial holes or ducts 3 connect the central hole 2 with the periphery of the block. The block I is provided with a number of bores or hydrocyclones 4 whose axes are arranged on two cylinders coaxial with cylindrical block I. The bores are of diminishing diameter and extend from one end to the other end of block. I, the narrow ends of the bores pointing in the sam direction. All hydrocyclones 4 have: the. same dimensions and one infeed entrance 5 debouching tangentially thereinto. All the infeed entrances 5 are situated in one plane perpendicular to the axis of the cylindrical block I. The infeed entrances of the outer hydrocyclon are connected with the periphery of block I whereas the inieed entrances of the inner bores are connected with the central hole 2. Every hydrocyclone 4 consists of a cylindrical part 5 into which the infeed entrance 5 debouches, a conical part 'I and a cylindrical discharge aperture or apex opening 8. The cover-plates 9 cover the bores 4 and the infeed entrances 5, so as to form the base of the hydrocyclones. In the drawings only a few coverplates 3 are shown so that the features of the body block I are visible, but it is obvious that every bore 4 and every infeed entrance 5 has to be covered when the multiple hydrocyclone is operated.

The cover-plates 9 are provided with tubes or vortex-finders I0 co-axial with the bores 4 they cover and extending into the bores and in the opposite direction. To hold the vortex-finders It in the centres of the hydrocyclones 4 the body block I is provided with an extension II wherein spaces are left which fit around the cover-plates 9, preventing them to move sideways. The block is further provided with a resilient outer collar or flange I2 and a resilient inner collar or flange l3 both connected with the apex end of block I, the loose-end of the outer collar I2 encircling the block and the loose end of the inner collar I3 being situated within the central hole 2.

Figures 5 and 6 show an assembly with two soft rubber multiple-hydrocyclones in series. The casing 14 comprises an outer tube I5 which surrounds multiple-hydrocyclone I, while fitting closely around the outer collar I2 of the block. The inner tube I6 fits closely in the inner collar I3 of the multiple-hydrocyclone. Cover I! is a circular member provided with circular perforations I8 surrounding the vortex-finders I0. Bottom I9 is a circular plate provided with a central perforation 29 surrounding inner tube I6 and with circular perforation 2 I facing the apex apertures 8 of multiple-hydrocyclone I. The outer tube I5 and the inner tube I6 are connected by wall 22 opposite bottom l9. Between wall 22 and bottom I9 there is a discharge opening 23 leading to tube 24 and valve 25. Wall 22 is provided with an infeed connection 26 for inner tube I6. The outer tube I5 is provided with a flange 21 perforated for. receiving the bolts 28 which can be tightened by nuts 29. The cover I! has a cylindrical part 30 and a flange 3I, so that the cover IT can be brought into the outer tub I5 with flange 3I resting on flange 21, tightening. the cover-plates 9 against the block I in the meantime. The opposite side of flange 3I meets casing 32, which is similar to casing I4 but which has no part corresponding'with infeed connection 26. Number 33 refers to an outer tube, 34 to an inner tube, 35 to a cover with perforations 36, 31 to a bottom. with a central perforation or aperture 38 and circular perforations 39, 40 to a well, M to a discharge openingleading to tube 42 and valve 43, 44' to a perforated flange of outer tube 33, 45 to the cylindricalpart of cover 35 and 46 to the flange of cover 35. On top of flange 46 is a closing member 41 perforated for receiving the bolts 28 and a discharge aperture 48 leading to tube 49 and va1ve.5fl. Insid casing 32 is multiple-hydrocyclone 5|, similar to multiplehydrocyclone I and showing the same features. Packing, 52 is provided between the flanges Z'I'and 3I, between H and 32, between 44 and 46 and between 46 and 41 to prevent leakage. By tightening the five .nuts 29 all separate parts of the multiple-hydrocyclone and the casing are clamped together.

In operation the material to be treated, e. g. a starch suspension, is introduced continuously under pressure into the inner tube I6 and enters central hole 2 of multiple-hydrocyclone I. The pressure of the suspension presses the loose end of collar I3 against th outer surface of inner tube I6 so that no suspension can leak out. Part of the suspension passes through the radial holes 3 and enters the space between block I and the inner surface of tube I5. The pressure of the suspension forces the loose end of collar I2 against the inner surface of outer tube I5 so that no suspension can leak out. The suspension therefore is led through the infeed entrances 5 into the bores of hydrocyclones 4. The inner hydrocyclones receive suspension from central hole 2 directly, Whereas the outer hydrocyclones receive suspension from the space between the block I, and the outer tube I5. Rotating bodies of suspension come into being in the cylindrical parts 6 and conical parts I of the hydrocyclones 4 and the separated fractions are discharged through the apex openings 3 and through the vortex-finders ID. The apex-discharge of the multiple-hydrocyclone is received in a space confined by wall 22, bottom I9, inner tube I6 and outer tube I5 and is discharged therefrom through discharge opening 23, tube 24 and valve 25. The vortex-finder-discharge is received in a space confined by cover I! and wall 40 and closed by packing 52 and enters through inner tube 34 into the central hole 2 of multiple-hydrocyclone 5|. The operation of multiple-hydrocyclone 5i I corresponds with the operation of multiple-hydrocyclone I. The apex-discharge of multiplehydrocyclone 5|, 1. e. the second apex discharge,

- is received in a space confined by wall 45, bottom 31, inner tube 34 and outer tub 33 and is discharged therefrom through discharge 4!, tube 42 and valve 43. The vorteX-finder-discharge of multiple-hydrocyclone 5I is received in a space confined by closing member 41 and cover 35 and closed by packing 52 and is discharged through aperture 48, tube 49 and valve 55.

The operation of the mu1tiple-hydrocyclcnes I and 5| can be controlled by adjusting the valves 25, 43 and 50 and by regulating the infeed pressure in inner tube I6.

The assembly shown in Figures 5 and 6 contains two multiple-hydrocyclones of twenty-four hydrocyclones each, yet only four outer pipe con.- nections are required. The suspension exerts pressure on the blocks from all sides and the blocks therefore are only slightly deformed, even if they consist of an easily deformed material.

The separate hydrocyclones thus retain their circular shape. This makes it possible to cast or mould the multiple-hydrocyclones of soft rubber, which is of great advantage because soft rubber is wear resistant and has a smooth surface and is therefore especially suited for the inner surface of small hydrocyclones.

The same units as described in Figures 5 and 6 may be used to assemble three multiple-hydrocyclones in series, so that every casing contains 72 hydrocyclones. Such an assembly is especially useful for the thickening of starch suspensions.

A similar assembly with two multiple-hydrocyclones in parallel is shown in Figure 7. The suspension is introduced through tube 53 into a space surrounded by cylindrical member 54 and U is divided into two parts, both parts passing into an inner tube 55. The assembly further comprises casings 56, outer tubes 51, inner tubes 55, covers 58 with perforations 59, bottoms Bllwith central perforation 6| and circular perforation B2, walls 63, discharge openings 64 leading to tubes 65 and valves 65, perforated flanges 61 of outer tubes 51, cylindrical parts 68 and flanges 59 of covers 58, closing members 10, perforated for receiving the bolts II which can be tightened with nuts l2, discharge apertures 13 leading to tubes I4. Packing i5 is provided between parts of the casing to prevent leakage. Inside the easings 56 are multiple-hydrocyclones 16 similar to multiple-hydrocyclone I.

The assembly as shown in Figure '7 contains 48 hydrocyclones, yet only 5 pipe connections are required. In a factory requiring one thousand small hydrocyclones only 21 apparatus as shown in Figure 7 have to be installed.

We claim:

1. Apparatus for a multiple-hydrocyclone comprising a cylindrical block with a cylindrical hole centrally therethrough and radial holes connecting the central hole with the periphery of the block, bores of diminishing diameter from one end to the other end each bore having at its large end an infeed entrance tangentially debouching thereinto, the axes of the bores being arranged on two cylinders co-axial with the block, the infeed entrances of the bores of the inner cylinder being connected with the central hole, the infeed entrances of the bores of the outer cylinder being connected with th periphery of the block, a cover-plate for each bore and the infeed entrance thereto with each coverplate having a co-axial aperture therethrough for each bore and a tubular member extending axially from the cover plat into the bore and in the opposite direction, an outer and an inner resilient collar connected with the block at the edge where the bores have their smaller ends, the loose end of the outer collar surrounding the block, the loose end of the inner collar lying within the central hole, all bores with th infeed entrances debouching thereinto and the apertures leading therefrom defining identical hydroing a casing encircling the block and a cover plate as well as a bottom plate with an infeed tube wherein the outer collar closingly co-acts with the casing and the inner collar closingly co-acts with the feed tube.

2. A casing for apparatus according to claim 1 comprising an outer tube whose inner diameter is larger than the outer diameter of the cylindrical block but smaller than the largest diameter of the resilient outer collar therearound so that said collar closes the opening between the multip-le-hydrocyclone and the outer tube, an infeed tube whose outer diameter is smaller than the inner diameter of the central hole of the multiple-hydrocyclone but larger than the smallest diameter of the inner resilient collar therein so that said inner collar provides a closed connection between the infeed tube and the multiplehydrocyclone, a cover with apertures arranged as to correspond with the discharge apertures of the hydrocyclones to cover the end of the multiple-hydrocyclone at the end opposite its collars. a bottom with apertures arranged as to correspond with the infeed tube and with the discharge apertures of the hydrocyclones to cover the collared end of the multiple-hydrocyclone and means to clamp the outer tube, the infeed tube,

discharge opening has regulating means.

6. A multiple-hydrocyclone comprising a cylindrical block having an axial hole therethrough and therearound a plurality of axially disposed cylindrical bores large at one end and of diminishing diameter at the other smaller end, cover means for the large ends having an aperture therethrough for each, an apertured bottom plate closing an end of the block whose apertures form an outlet area therethrough for liquid discharging from the smaller end of the bores, an apertured top plate for the other-end of the block whose apertures form an outlet area therethrough for liquid discharging from the large end of each bore,-clamping means connecting the top plate and the bottom plate, conduit means for carrying away liquid discharging through the bottom plate,

conduit means for carrying away liquid discharging through the top plate, means for feeding a suspension to be treated by the hydrocyclone into the-central hole as a receiver of a common supply of feed, and means for distributing feed from the hole to the bores having an individual feed-con-' ducting passageway leading from the common feed supply and debouching tangentially into the large end of each bore.

'7 A multiple-hydrocyclone according to claim 6, with the addition of a casing encircling the a block at its side but constructed and arranged to leave a liquid holding space between it and the block, a further plurality of bores and associated cover plates in all respects like the first plurality thereof except that their feed entrance passageways connect each of them with said space, and liquid-conducting conduit means connecting the hole with said space.

A multiple hydrocyclone according to claim 6, wherein the suspension feeding means include tubular means projecting through the bottom plate, with the addition of resiliently deformable liquid-sealing means between the tubular means and the block.

9. A multiple hydrocyclone comprising a block with a central axial hole and parallel to that hole aplurality of substantially conical bores of diminishing diameter with all the base outlets at one end of the block and all the apex outlets at the other end of the block, apertured top cover means for closing the base outlets of the bores except for an aperture aligned therewith, apertured bottom cover means having an aperture area to form an outlet for liquid discharging therefrom, pressure means including a tube for feeding a suspension to be treated in the hydrocyclone into the central hole, and a feed-conduct ing'passageway tangentially debouching into the large end of each bore leading from the feedreceiving hole whose common feed supply is thus flowed through the feed passagewaysand distributed individually to the'bores.

10. A multiple hydrocyclone according to claim 9, with the addition of a chamber for collecting discharge from the base outlets of the bores anddischarging it after being so collected, and of a chamber for collecting discharge from the apex outlets of the bores and discharging it'after being so collected.

11. A multiple hydrocyclone according-to claim 10, wherein the tube for conductingthe incoming feed passes through the chamber that collects discharge from the apex outlets.

12. A mu'ltiplehydrocyclone according to claim 11, wherein there are two such complete assemblies arranged in superposed position with the outlet from the casing that collects discharge from-one set of similar outlets of the subjac'ent assembly comprising the tube that feeds to the central hole of the superjac'ent assembly.

13. A multiple hydrocyclone having a generally cylindrical casing with apertured cover means and an apertured bottom, an annular block with a feed-receiving central hole located co-axially within the casing having an inner and an outer ring of similarly directed substantially conical bores therethrough each of which bores is a hydrocyclone with a base outlet discharging through an aperture in the cover means, as wen as an apex outlet discharging through an aperture in the bottom, outwardly extending liquidsealing means extending between the block and its casing at an levation between said outlets to provide there a feed-receiving annular space between the block and its casing above the sealing means, inwardly extending liquid-sealing means extending from the block into its hole at a similar elevation, fe'ed conducting ducts extending through the block from its hole to the annular space, an infeed entrance to each of the bores of the inner ring leading from the hole, an infeed entrance to each of the bores of the outer ring leading from said space, and a tube projecting eontactingly past the inwardly extending liquid-sealing means into the hole for conducting incoming feed thereto for distribution to each feed entrance of the bores of the inner ring thereof directly from the hole and t'oe'ach feed entrance of the outer ring thereof indirectly from the hole through the radial ducts and said annular space.

14. A multiple hydrocyclon'e having a casing with an apertured cover and an apertured bottom, a block with a feed-receiving central hole located within the casing having an inner and an outer ring of similarly directed substantially conical bores therethrough each of which bores is a hydrocyclone with a base outlet discharging through an aperture in the cover as well as an apex outlet discharging through an aperture in the bottom, the block being spaced from its casing {or a portion of its length above the apex outlets to provide there an annular feed-receiving space, feed-conducting duct means extending through the block from its central hole to the annular space, an infeed entrance to each of the bores of the inner ring leading from the central hole, an infeed entrance to each of the bores of the outer ring leading from the annular space, and a tube projecting sealingly into the central hole for conducting incoming feed thereto for distribution to' each feed entrance of the inner ring of bores directly from the hole and to each feed entranceof the outer ring of bores indirectly from the hole through the duct means and the annular space.

FREERK J. FONTEINL JAN N. J. LEEMAN.

(References on following page) Number Number .9 10 References Cited in the file of this patent Number Country Date 880,715 France Apr. 2, 1943 UNITED STATES PATENTS 607,777 Great Britain Sept. e, 1948 Name Date Leopold Aug. 24, 1886 5 OTHER REFERENCES Greer et a1.: Preliminary American Tests etc., FOREIGN PATENTS Feb. 1947, Aime T. P. 2136 in Coal Technology,

Country Date DD. 2 and 3. t; it Dec. 4, 1397 Driessen et a1.: Cyclone 'I'hickener, Mining Great Britain 13, 1903 10 Technology, vol. 181, Jan. 1950. Great Britain May 2, 1930

Images