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Publication numberUS2349469 A
Publication typeGrant
Publication dateMay 23, 1944
Filing dateAug 14, 1941
Priority dateAug 14, 1941
Publication numberUS 2349469 A, US 2349469A, US-A-2349469, US2349469 A, US2349469A
InventorsEdward C Sloan
Original AssigneeJesse B Hawley
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Filter
US 2349469 A
Images(2)
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Description  (OCR text may contain errors)

May 23, 1944.

E. C. SLOAN FILTER Filed Aug. 14, 1941 2 Sheets-Sheet 2 l mi.-

,S INVENTOR. @am/d k6 SLQZWQQ..

III",

BY@r @D Patented May 23, 1944 OFFICE'.-

2,349,469 FILTER n i Edward Sloan, Geneva, Ill., assixnor to Jesse B.

Geneva, Ill.

Application Ailtust 14, 1941, Serial No. 406,830

(Cl. 21o-204) Hawley,

7 Claims.

vplurality of shell carcasses and so treating the libers that the treating material will be uniformly distributed on the bers throughout the carcass. A still further object is to dissolve a resin in the bath of fibers and water, and accrete a shell carcass onto a former of the desired form, so

that when the water is evaporated by drying, the resin will be uniformly distributed on the fibers throughout the carcass.

Another object is to add in suitable amount in the bath of fibers and water, diatomaceous earth thoroughly mixed inthe b'ath, so that the diatomaceous earth will control the degree 'of porosity of a carcass accreted onto a former immersed in the bath.

Still another object is to mix in a brous pulp bath diatomaceous earth, and resin in solution, to cause the diatomaceous earth to remain' uniiormly distributed throughout the fibrous structure of a carcass accreted onto a former of the desired shape in the bat An additional object is to add, in the desired manner resin of the desired kind, to a fibrous pulp bath, so that in a carcassaccreted onto a porous former in said bath, and when dried, the resin will stabilize the fibers and the structure and keep the fibers from softening or swelling in the presence of water, thus waterproofing the fibers. desirable because it would decrease the porosity of the structure. By the present invention the resin will add to the rigidity of the fiber structure, thus further waterproofing the fibers and causing the corrugations orother roughened surfaces to remain stili and eilective in the presence of Water, and further will keep the structure from rupturing under pressure.

A further object is to so treat the iibers'as such in the bath and thus afford the opportunity to stillen the fibers by the use of the proper and desirable resins so, that the accreted dried structure will have a decidedly indenite, irregular,

indeterminate, rough and shaggy surface to lessen the possibility of a coating or film being formed to close oil the porosity.

Such softening or swelling would be unto a second bath stage filter in which the various stages leach comprise a pair of brous shells for effecting a certain selected stage of ltering.

A further object is to provide a iilter in which a large mass of bers is accreted in a bath, either with or without resin, onto a perforated core, spool or the like to enable such lter to be easily inserted within a filter casing and readily removed therefrom for renewal when desired and, if desired, such filter may have a plurality of layers of different porosity.

Another object is to first accrete onto a porous former a brous article in a bath not containing resin, and then remove the article thus accreted to a second bath containing resin, and by suction or pressure cause some of the liquid in the resin bath to pass through the interstices of the brous article to supplant the of said article.

Other objects, advantages and capabilities will later more fully appear. My invention further resides in the combination, construction and arrangement of parts i1- lustrated in the accompanying drawings, and while I have` shown therein preferred embodiments, I wish it understood that the same are susceptible of modification and change without departing from the spirit of my invention.

In the drawings: y

Figure 1 is a fragmentary longitudinal section of a portion of a filter member embodying my invention.

Fig. 2 is a similar view of another form of my invention.

Fig. 3 is a. similar view of still another form of my invention.

Fig. 4 is a vertical longitudinal section showing a single stage filter member with parts broken away for convenience.

Fig. 5 is a View Similar to Fig. 4, but showing a multiple stage filter member embodying my invention.

Fig. 6 is a vertical longitudinal section through. lilter casing and filter member therein, the lter member being of the mass type instead of the shell type shown in the preceding views.

Fig. 7 isa perspective view of the filter member of the type shown in Fig. 6.

Fig. 8 is a transverse, vertical section through a tank containing a felting bath and a porous felting former, and atransferr'er thereabove for carrying an accreted carcass fromthe rst bath for further treatment. similar to Fig. 8 but showing a water among the fibers Fig. 9 is a view A still further object is Vto provide a multiple second bath containing resin or the like, a porous felting former in the second bath, and the transferrer thereabove.

Fig. is 'a reduced transverse, vertical section of an oven or the like for drying the wet carcasses. Referring more in detail to the drawings, Fig. l shows in section a fragment of a wall of a filter member vembodying one form of my invention. In this form the filter member is preferably formed by accreting it in a fibrous pulp bath onto a porous former of the desired shape by a differential of pressure which may be applied as a partial suction or otherwise as desired. In Fig. 1 the rst layer of the filter member may be a screen l of metallic or textile material-as desired placed against the porous outer surface of the former inthe pulp bath; or this inner screen may be omitted if desired. As any shape or type of porous former desired may be used, and as the suction of `ilbers onto a porous former in a pulp bath is well known, I have shown in Fig. 8 a. simple form of apparatus for the general operation of felting or accreting a brous pulp carcass or shell in a bath, but without limiting the present invention to the particular shapes shown. In producing the lter wall shown in Fig. 1 inert material such as diatomaceous earth is mixed into the brous pulp bath, without the addition into the bath of any resin. As the fibers and diatomaceous f earth are sucked or otherwise forced against the surface of the porous former the earth particles 2 will pass through the interstices of the deposited bers and become more or less concentrated near' the inside surface of the lter carcass being formed, leaving the bers 3 of the outside portion of the carcass more porous, and those on and near the inside surface less porous. In a filter of this type the'outer, more porous portion of the filter wall will filter out the larger suspended matter in the fluid being filtered, while the less porousinner portion of the wall will filter out the nner suspended particles. The porosity ofthe filter walls may thus be controlled as des'ired by using either fine or coarse inert material, or amixture of both fine and coarse. Also the degree of filtering may he further controlled by accreting the walls thicker or thinner and with nne or coarse bers either with or without the addition of inert material.

Examples of some ofthe inert materials that may be used in carrying out my invention are diatomaceous earth, vermiculite, kieselguhr, fullers earth, and the like. Also it is to be understood that while my invention preferably contemplates the use of my novel lter members in filtering oil andthe like, it is not to be limited thereto, but may be used for filtering any uids to which my lter members may be adapted.

Another form ofmy invention is shown in Fig. 2 in which a suitable resin is added to the fibrous pulp bath, as a result of which I have discovered that the inert material is given uniform dispersion and distribution throughout the interstices of the iibers, instead of concentrating on the inner layer as in Fig. l. In Fig. 2 the inner screen member I may be used or omitted as desired, and as shown in this view of the drawings the particles of inert material 2' are distributed uniformly throughout the brous wall. This phenomenon of the uniform distribution of the particles of inert material when resin is used in the bath is of great importance in that it enables close control of the porosity by. controlling the kind and amount of inert material used. Awater soluble resin is preferable but I dov not wish the invention to be unnecessarily limited thereto.

Some of the resins that are suitable in carrying out my invention include phenol formaldehyde, cresylic acid formaldehyde, meta-para cresol, urea. formaldehyde, thiourea formaldehyde, and the like, or the foregoing the formaldehyde; these resina being in the .A stage in which the condensation has been arrested before the resin has become hydrophobic. Thesel resins may be dissolved in water so that the percentage of solids is from 3% to 7% by weight which amount of solids will be sufficient for the stiifening, water-proofing and giving of wet strength to the fibers of the lter members as more fully described later herein.

In Fig. 3 is shown a fragment of a. portion of the fibrous filter member wall in which the surface first meeting the oil or other fluid being filtered is extremely rough, shaggy, indefinite, indeterminate or irregular as indicated at l so as t0 lessen the possibility of a coating or film being formed to close off the porosity, as a film forming substance would have the tendency to attach itself to the iirst part of the surface with which it comes in contact. The porosity away from the surface of the filter may be great or less as desired. A giverf amount of film forming material will have less tendency to form a continuous film-and thus close oil or stop the `effectiveness of the ltering area-where thel indefinite or shaggy surface is present as in Fig. 3 to lter out the film forming material. This tendency to prevent the formation of a film on the filter surface may be better understood by likening it to the uneven, shaggy appearance of a lawn of more or less high grass in the spring when a. light fall of snow falls on the same.

In Fig. 3 as in Fig. 2, resin is added to the' pulp bath from which the filter member is accreted. As stated water-soluble resin is preferred. This resin is dissolved in the bath in desirable proportion. A suitable proportion is to dissolve 5% by weight of solid resins in the bath water in which the fibers to be accreted on the former are suspended. and prior to drying a 30 gram filter carcass will have approximately grams of water containing 5% solid resin. When the carcass is dried the 5% or 4 grams of resin remains in the carcass or iter shell, distributed uniformly throughout the bers. The resin has also to a certain extent entered the fibers themselves as well as coating and joining the fibers. This method of treating the fibers as such in the bath Waterproofs the fibers by using the proper resins and stiiens the fibers.

A further advantage in treating the fibers of the filter unit with resin is that the resin stabilizes the fibers and the structure, and prevents the fibers from softening or swelling in the presence of water, should some water pass through the interstices of the filter when filtering oil or other fluids. Should the fibers become soft or swell (as they will not do with the present invention) this would decrease the porosity of the structure which is undesirable, and might even lead to the rupture of the filter unit.

Referring back to Fig. 2, the incorporation of resin in the filter unit as described, will not only keep the inert material uniformly dispersed and distributed with relation to the fibers, but it will also allow a greaterthickness of accretion with a given uniformity of porosity. The resin in the bath prevents the inert-material from gathering in clusters or layers in the ilbersandinsures with lfurfural replacing When accreted or felted 1 words, it stabilizes the uniformity of distribution both during the making of alter unit and in its use. The increasing of the wet .strength of the bersas described above will -also render them water-proof as will be readily understood.

In Fig. i is shown a double shell single stage lter unit comprising an outer-shell and an inner shell 6 with the upper edges secured together by stitching, sewing, stapling or the like 'i to close that end of the lter unit. The base portions 8 and 9 of the outer and inner shells 5 and 8 respectively are formed with registering central openings around. the edges of the mate.

Fig. 6, or of any other suitable shape and construction desired. In operation the oil or other uid to be ltered will enter the lter casing I 4 at I5, then pass through the shells 5 and 6 to the space I6 therebetween, then through the apertures i3 of sleeve I2 and out through any suitable outlet opening provided in the base of the filter and associated parts.v

In Fig. 5 is shown a multiple stage lter unit comprising four shells I1, I8, I9 and 2l) arranged in two pairs of which shells I1 and i3 form one pair having a. reinforcing collar 2l in the openings of the base portions, and shells I9 and 2D form another pair having a reinforcing collar 22 in the openings of their base portions. These shells will be stitched, sewed, stapled or otherwise secured together at their upper edges asv indicated at 23 for a purpose similar to that described above in connection with Fig. 4. The two stage lter unit of Fig. 5 will be inserted in filter casing M or other suitable casing in the manner suggested above in connection with Fig. 4. In the lter unit of Fig. 5 much greater efficiency in ltering may be achieved however, because the outer and inner shells il and 20vmay be of different construction from the intermediate shells it and i9 to give added filtering possibilities. For example, the outer and inner shells Il and 2t may be of medium coarseness to lter out the sludge or heavierparts of the dirt in the oil or the like, and the two intermediate shells it and i9 may be of much ner porosity so as tov lter out particles which color the oil black or gray, by having a combination of bers and inert material, or bers, resin and inert material-in their composition as desired. The oil or other uid being ltered would first ow inwardly through the shells l1 and 20 into spaces 23' and M to eiect the rst stage of ltering, and thence ,3 lteris shown in Fig. 6 in/vertical cross section. The bers used in accreting this type of lter are preferably rock wool. but other kinds of bers may be used if desired. As seen in Fig. 6 the casing I4 is provided with an inlet IS'and an outlet 2l, the cover 28 vbeing removable by removing the hollow stud 3I' to permit insertion into the lcasing and removal therefrom of the perforated spool orcorev 29 upon which the rock wool 30 vor other bers are accreted. As seen in Fig. 6 the thickness of the accreted bers 30 is considerable. As shown the core 29 is perforated to permit the oil or other `iiuid toy pass therethrough (after.

passing through the rock wool bers) and thence out through the outlet 28, there being provided in the walls of the hollowstud 3i openings 43l. to permit the passage of the filtrate. The hollow stud 3| is threaded into the base 21 at 33 to permit tightening and removal ofthe parts, and above the upper cover or hub cap 34 of the spool is a coil spring 35 to force the lter unit downwardly. l 'Ihe spring 35 is held under compression between the cap 34 and the shoulder 36 of the head 3T, there being interposed a. gasket 38 between the head 31 and the lter casing cover 28 to prevent leakage. A cloth covering is preferably applied over the outside of the core 29, to prevent the bers from passing through through shells I8 and I9 into space 25, and then through the outlet perforated spacer 2Ia to any desired receiving means to effect the nal ltering and, if desired, a brightening of the oil. Also if desired, the rst stage might be composed of coarse water-absorbing fibers to absorb water that may be entrained in the oil, so that water as such will not impair the efficiency of the later stage or stages.

M'y invention further contemplates the production of lters for oil and other uids in which the` filter unit is accreted onto a perforated hollow core or spool, the accreted lter portion having considerable mass and thickness. Such a holes h in the core.

Fig. '7 shows how the accreted bers 30 together with the core 29 may be made separate and installed in the spool when fresh and removed j therefrom as a lter unit after use. Also the core 29 may have the rock Wool bers accreted thereon to any desired thickness by providing removable ends 39, 40 to the core 29 while in the accreting bath to define the shape of the ends of the accreted bers, or other removable blank ends of the desired width may be applied to the core during accreting as desired to dene `the ends of the lter unit. The accreted bers of the form of lter shown in Figs. 6 and 7 may have resin, or inert material or both in desired proportions incorporated therein during accretion, as

set forth earlier herein in connection with the description oi Figs. 1 to 3l inclusive, and fora similar purpose. A gasket 4l is provided betweenthe outer edge of the casing cover 28 and the upper edge of the filter casing to prevent leakage. I may also provide three layers a, b and c (see Fig. 7) of different porosity, for example, these different layers maybe of different neness of bers, and may have diatomaceous earth or the like in one or more but with resin in all of the layers. In other words, the layers will be so constructed in one or the other of the diierent ways heretofore described so as to have different porosity inthe dierent layers as desired, with the coarser porosity in the outer layer, a ner porosity in the next layer and a still ner porosity in the inner layer so as to give different degrees of ltering in the different layers. Any greater or less number of layers may be used as desired.

My invention also contemplates the accreting bath and immersing it into a second bath containing resin in solution in water and pulling or forcing by suction or .pressure the resin solution through the said accreted article and supplanting the original water remaining in the interstices in the article, with the resin solution, and drying the article by removing the water andleaving the resin impregnation in and on the bers.

ings in the former and depositing the fibers thereon to form a` carcass or shell designated generally in Fig. 8 at i6'.

The hose 53 is formed with a c0115! in order to permit the former 52 to be moved upwardly out of the bath, or downwardly thereinto Ias desired.

`Coil 54 passes through the wall of tank 5l) and connects with the manifold 55, into which extend the air pressure pipe 5B and the `suction pipe 51, which latter two pipes will be connected with any suitable means of air pressure and suction. Pipes 56 and 51 are controlled by valve 58 which may be operated to connect either the air pressure line or the suction line as desired to the hose 53 so as to create either a suction on the interior of the porous former or introduce air pressure thereinto selectively. The former and wet carcass are shown in dotted lines just above the tank 50.

Above the tank 50 is a transferrer 59 for receiving and transferring the wet carcass to the second tank 60 containing a fiber-water bath 6i having resin included therein. Transferrer 5 9 is formed on its interior with the porous shell 62 of substantially the same internal size as the exterior of the wet carcass l 6', and into which holllow interior the wet carcass is introduced by moving the former 52 upwardly thereinto, `ai'ter which the valve 63 will be operated to introduce from a suitable source of supply a suction in the space 5I so as to cause the wet carcass to adhereto the interior of the transferrer. If desired, this can be further facilitated by introducing air under pressure into the interior of the former to tend to force the wet carcass away from the exterior of the former 52, after which the'former will be lowered again into bath 5|, the air pressure cut off and suction introduced into the former to accrete another carcass thereon.

As soon as the former 52 has deposited its wet carcass on the interior of the transferrer and the former lowered away from the transferrer, the latter will be moved by any suitable means into the position shown in Fig. 9, after which the former 651s introduced thereinto and suction created in the former 65 to suck the wet carcass thereagainst. At thesame time, the suction in the space 64 of the transferrer will be cut off and any desired amount of air pressure introduced through pipe 66 into space 64 to further cause theqwet` carcass to grip the exterior of the upstanding porous portion of former 65, thus causing the carcass to adhere to the former.

The former 65 with the we t carcass thereon is shown in Fig. 9 midway between the transferrer and tank 50. The former 65 together with the wet carcass I6 thereon will then be lowered into .as-raies shown in Fig. 9 not used, the resin will be added to bath 5I. When, however, the resin is added to bath BI, there will be no resin added to bath 5l but the carcasses will be accreted without resin in bath 5I and then introduced as described above into bath 6I containing resin, which results inf the suction in former B5 carrying the resin containing liquid through the carcass and incorporating resin into the carcass in the form shown in Fig.9. In Fig. 9, the manifold 55', air pressure pipe 56', suction pipe 51' and valve 58' are similar to the corresponding parts described in connection with Fig. 8.

In Fig. 10 is shown a heating oven 1li through which the carcasses I6' may be passed for drying,

hot air being introduced from any suitable. source of supply through the pipe 1|- and perforated discharge head 12, a chimney 13 or outlet pipe being provided as desired.

Having now described my invention,

l. A filter member comprisinga body of ac- Icreted, interlaced Vfibers coated with resin', diatomaceou's earth in the interstices of the body, the diatomaceous earth being uniformly distributed throughout the interstices of the fibrous body to control the degree of porosity of *the filter mem-ber, the resin being of such character and so applied that it assists in effecting said uniform distribution. i

2. A filter member comprising a Ibody of accreted, interlaced fibers coated with resin, and having particles of inert material in the interstices of the fibrous body to control the degree of porosity of f the lter, the resin being of such character and so applied that it assists in effecting uniform distribution of the inert material throughout the interstices of the fibrous body and to stabilize the fibers and prevent them from softening and swelll ing in the presence of water.

3. A filter member comprising a body of accreted, interlaced bers, said fibrous body having tank B0 into the position shown in Fig. 9, and

bath 6i is resin similar to that previously de-A scribed in connection with Figs. 1 to '1.

When the carcasses are formed solely in a single bath such as shown in Fig.' 8, and the bath incorporated therethrough resin and diatomaceous earth, the exterior surface of the filter member being irregular, indefinite and shaggy to prevent the formation of a film thereon that would tend to clog the interstices between the fibers, the presence cf the resin on the fibers causing them to be rigid and maintain the irregular and shaggy condition, land the diatomaceous earth controlling the degree of porosity of the filter, the `diatomaceous earth being uniformly distributed throughout the interstices of the fibers. l

4. In a multiple stage filter, a plurality of pairs of accreted, fibrous pulp shells, said shells being in concentric relation and secured together around one edge, the two shells of each pair each having an opening ih its central bottom portion and secured together around said opening but unattached with relation to each other from said opening to the opposite secured ends, perforate means for spacing the apertured central bottom of each pair, said pairs being positioned concentrically one pair within the other, whereby the fluid being filtered will pass first through one shell of each pair into the space between each pair of shells, and then through the other shell of each pair into the space between pairs, and then out through said' perforate means.

5. lIn a multiple stage filter, a plurality of pairs of accreted, brous pulp shells concentrically positioned one witlin the other, the walls of veach pair of shells and .the walls of all pairs being secured together at one end, means securing the other ends of the walls of each pair together with one pair in spaced relation to the other pair and for forming an outlet from the space between the pairs. whereby the fluid being filtered will pass inwardly through the exterior wall of each pair to the space within each pair. and then through the interior wall of each' pair to the space between the pairs and ,out through said outlet from the `space between the pairs. i

6. In a multiple stage iilter, a'plurallty of pairs of accreted, brous pulp` shells concentrically positioned one within the other, the walls of each pair of shells and the walls of all pairs being secured together at one end.' means securing the other ends of the .walls ofeach pair togetherwith one pair in spaced relation to the other pair and for forming an voutlet from the space between the pairs, whereby the huid-beine filtered will pass inwardly through the exterior wall ofv each pair to the space within eachl pair, and then through the interior wall of each pair to the Space between the pairs, the exterior shell of each pair having greater porositythan the interior shell of each pain'and means `for draining the filtered fluid out through said outlet from the space between the pairs.

' other end and secured together around said open f ings but unattached with relation to each other from the end having the opening to the opposite secured ends. perforate means for spacing apart the apertured central portions of the two pairs, said pairs being positioned so that the uid being iiltered will pass first through one shell of each pair into the space betweeneach pair of shells, and then through the other shell of each pair into the space between pairs, and then out ,i through said perforate means, the fibers of the shells of one of said pairs being coated with resin and having particles of inert material uniformly distributed in the lnterstices between the bers thereof, the resin' being of such character and so applied that it assists in effecting said uniform distribution.

EDWARD C. SLOAN.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2430713 *May 8, 1944Nov 11, 1947Int Harvester CoOil filter
US2435115 *Nov 19, 1943Jan 27, 1948Samuel AlsopFilter
US2468862 *Oct 22, 1943May 3, 1949Southwick W BriggsFluid filtering element
US2647639 *Aug 12, 1948Aug 4, 1953Grein Raymond CApparatus for cleaning tanks and the like
US2675127 *Jun 14, 1951Apr 13, 1954Purolator Products IncOil filter element construction
US2692683 *Apr 9, 1951Oct 26, 1954Mason Veyne VFilter
US2742160 *Jun 14, 1951Apr 17, 1956Joseph W FogwellFilter cartridge
US2746608 *Mar 16, 1951May 22, 1956Southwick W BriggsFilter element and method of making same
US2768754 *Aug 12, 1948Oct 30, 1956Southwick W BriggsBonded sawdust filter medium
US2893561 *Mar 7, 1958Jul 7, 1959Fram CorpMagnetic filter elements
US2898293 *Dec 28, 1953Aug 4, 1959Gulf Research Development CoWax sized paper
US2923068 *Jan 13, 1958Feb 2, 1960Diamond National CorpDrying die
US2953249 *Mar 1, 1955Sep 20, 1960Bowser IncFilter and dehydrator
US2959289 *Apr 4, 1956Nov 8, 1960Briggs Filtration CoFilter and dehydrator
US2971907 *Aug 17, 1955Feb 14, 1961Smith Walter JFilter media and method of making
US3003643 *Oct 28, 1957Oct 10, 1961Johnson & JohnsonFilter media
US3083157 *May 21, 1959Mar 26, 1963Krueger James SFilter construction
US3244287 *Dec 21, 1962Apr 5, 1966Coleman Instr CorpContinuous filtration
US4730805 *May 15, 1986Mar 15, 1988Kabushiki Kaisha KumagaigumiForm for forming concrete
US4787597 *Feb 29, 1988Nov 29, 1988Kabushiki Kaisha KumagaigumiCloth faced form for forming concrete
US5374354 *Sep 24, 1992Dec 20, 1994Sundstrand CorporationMethod of increasing service life of oil and a filter in an integrated drive generator or constant speed drive and improved oil filter for use therein
US5435912 *Jul 20, 1994Jul 25, 1995Sundstrand CorporationMethod of increasing service life of synthetic oil and an apparatus for use therewith
US5500122 *May 11, 1994Mar 19, 1996UopStacked fluid-separation membrane disk module assemblies
US5520807 *May 11, 1994May 28, 1996UopStacked fluid-separation membrane disk module assemblies
US5536405 *May 11, 1994Jul 16, 1996UopStacked membrane disk assemblies for fluid separations
US5552040 *Dec 19, 1994Sep 3, 1996Sundstrand CorporationMethod of increasing service life of oil and a filter for use therewith
WO2008095230A1 *Feb 5, 2008Aug 14, 2008William BlissWater treatment
Classifications
U.S. Classification210/490, 210/447, 210/505, 210/347, 210/504
International ClassificationB01D29/00, B01D39/14
Cooperative ClassificationB01D29/0027, B01D29/0036, B01D29/0093, B01D39/14
European ClassificationB01D29/00B, B01D29/00A8, B01D29/00A10K14, B01D39/14