WO2019236517A1

WO2019236517A1 - Hybrid sintered polymeric particle and woven fabric filter media for industrial starch applications

Info

Publication number: WO2019236517A1
Application number: PCT/US2019/035294
Authority: WO
Inventors: Brent STOKES
Original assignee: Flsmidth A/S; Madison Filter 981 Limited
Priority date: 2018-06-06
Filing date: 2019-06-04
Publication date: 2019-12-12

Abstract

Hybrid filtration media includes a layer of woven fabric [110], a layer of sintered porous material [130], and a web of bonding material [120] between the layer of woven fabric [110] and the layer of sintered porous material [130]. The woven fabric [110] is preferably attached to the web of bonding material [120] to form a first laminate [160], and the sintered porous material [130] is attached to the web of bonding material [120] of the first laminate [160]. The hybrid filter media [170] is configured to withstand harsh industrial vacuum filtration environments, resist delamination, and be used on large industrial vacuum filters. A method of manufacturing a hybrid filter media is also disclosed.

Description

HYBRID SINTERED POLYMERIC PARTICLE AND WOVEN FABRIC FILTER MEDIA

FOR INDUSTRIAL STARCH APPLICATIONS

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. Provisional Patent Application No.

62/681 ,588, filed June 6, 2018.

FIELD OF INVENTION

This invention relates to filter media for industrial filtration apparatus, and further relates to a method of manufacturing belted filter media for use in the starch industry with pressure filtration devices such as the filter disclosed in U.S. Patent Application Publication No. 2007/0256984 (e.g., FLSMIDTH® PNEUMAPRESS® automatic pressure filter). In one embodiment, a laminated hybrid filter media for extracting liquids from a wet slurry fluid and for producing a substantially dry filter cake from solid materials in the slurry is provided.

The hybrid filter media may utilize supported or non-supported woven fabric material having a web of bonding material applied to it. The woven fabric material may comprise woven fibers which may be scrim-supported or unsupported. A sheet of sintered porous material, such as a polymeric sheet which is made up of one or more sintered polymeric particles, is applied to the web of bonding material to join the woven fabric material and the sheet of sintered porous material together to form a hybrid filter media product especially suited for filtering starch-containing slurries. US Patent Application Publication No. 2007/0256984 is hereby incorporated by reference herein for any and all purposes as if fully set forth herein. BACKGROUND OF THE INVENTION

Slurry, which typically contains solid particulates suspended in a liquid, is produced in many industrial processes. Often, it becomes necessary to separate the solids within the slurry from the liquid within the slurry so that each fraction of the slurry can be treated separately. Disposal of the liquid fraction (i.e. , filtrate) can be

economically costly due to its environmental impact. In most such processes or systems, the slurry material is fed to an industrial filtration apparatus which may take many forms including, but not limited to, a pressure filter (e.g., a pneumatic or stacked filter, such as the FLSMIDTH® PNEUMAPRESS® automatic pressure filter), without limitation. One particular non-limiting example of an industrial filtration apparatus especially-suited for starch slurry filtration is disclosed in US Patent Application No. 2007/0256984.

Industrial starch filtration processes pose a problem for filter media. Due to the physical properties of starch, filter media used with industrial starch filters must be replaced frequently due to wear and/or "blinding" caused by permanent clogging of woven filter media with fines dispersed and lodged between woven fibers. Moreover, effluent liquid (i.e., filtrate) leaving industrial starch filters can have high Biochemical Oxygen Demand (BOD) due to limitations in current filter media technology. Effluent filtrate having high BOD can increase economic penalties for starch producers if they exceed local environmental standards. Additionally, due to limitations in current filter media technology, the solids (i.e., produced cake) leaving industrial starch filters may be wetter than desired. There is, accordingly, a long felt need for industrial filter media which is more suitable for use in the starch filtration industry, and which can overcome the

aforementioned disadvantages in an acceptable manner.

In the starch, calcium carbonate, titanium dioxide, and magnesium hydroxide, and municipal wastewater management processes, upwards of 98% of production plants may rely on woven cloth filter media generally on the order of 1 mil thick. Such conventional woven filter media is easily damaged causing high solids content in the filtrate. When filtrate solids are exceeded, some plants (e.g., in the pigment industry) may be hit with large fines and penalties (e.g., sometimes upwards of $50,000 USD per day). Moreover, in many circumstances, blinding of filter media may hinder filtration efficiency in these processes leading to greater overhead, longer maintenance downtimes, and higher cake product manufacturing costs.

To date, there are no known filter media fabricators, filtration equipment manufacturers, or filter fabricators which combine sintered porous/micro porous sheets (e.g., formed from HDPE or UHMWPE particles) with woven fabric to form a robust flexible filtration media which is configured to dress large-scale industrial production pressure filters. Accordingly, new and improved filter media and methods of

manufacture thereof are needed - especially for use in the starch industry with filtering machines such as the one described in U.S. Patent Application No. 2007/0256984.

OBJECTS OF THE INVENTION

It is, therefore, an object of the invention to provide a hybrid filter media that is less susceptible to blinding or clogging, for example, in the starch, calcium carbonate, titanium dioxide, and magnesium hydroxide processes which are generally harsh on conventional woven filter cloths.

It is a further object of the invention is to provide a hybrid filter media which is configured to maintain its structural integrity, stability, and durability within large-scale industrial vacuum and pressure filtration processes.

It is yet another object of the invention is to provide a hybrid filter media that exhibits a reduced probability of delamination when mounting to an industrial filter, and which is less susceptible to abrasive slurry solids cutting into or pulling apart woven fibers.

It is another object of the invention is to provide a hybrid filter media which will hold up to aggressive bends around rollers, and which is adapted to handle large localized changes in tension and friction.

A further object of the invention is to provide a hybrid filter media which can provide upwards of ten to twenty times the filtration rate over conventional filter media in certain filtration industries and processes.

Yet another object of the invention is to provide a method of manufacturing a hybrid filter media which enhances the strength, durability, and filtration capacity of the hybrid filter media.

A further object of the invention is to provide hybrid filter media which enhances efficiency and filtration performance of industrial pressure filters, such as that of the pneumatic, stacked, and/or automatic pressure filter type. A further object of the invention is to provide hybrid filter media which enhances efficiency and filtration performance of industrial pressure filters, such as that of the pneumatic, stacked, and/or automatic pressure filter type.

Yet another object of the invention is to provide hybrid filter media which can be readily formed into a belt or continuous loop to configure the hybrid filter media belt configured to be mounted and rotated on two or more rollers (as shown in FIGS. 7 and 8).

Other details, objects, and advantages of the invention will become apparent as the following description of certain present preferred embodiments thereof and certain present preferred methods of practicing the same proceeds.

SUMMARY OF THE INVENTION

A method of making hybrid filter media for large industrial filtration devices is provided. The method comprises the steps of joining a layer of woven fabric with a web of bonding material and joining a layer of sintered porous material to the web of bonding material.

The step of joining the layer of woven fabric with the web of bonding material may, in some instances, comprise a laminating step to form a first laminate. In certain embodiments, the step of joining the layer of sintered porous material to the web of bonding material may comprise laminating the first laminate with the layer of sintered porous material. The step of joining the layer of sintered porous material to the web of bonding material may occur after the step of joining the layer of woven fabric with the web of bonding material.

In some preferred embodiments, the layer of sintered porous material comprises at least one polymer. The at least one polymer may comprise at least one of:

polyethylene, polypropylene, polyester, polycarbonate, polyvinylidene fluoride, polytetrafluoroethylene, polyvinylidene fluoride, ethyl vinyl acetate, polycarbonate, polycarbonate alloy, Nylon 6, thermoplastic polyurethane (TPU), polyethersulfone (PES), and polyethylene-polypropylene copolymer, without limitation. For example, the at least one polymer of the sintered porous material may comprise high-density polyethylene (HDPE) or ultra-high molecular weight polyethylene (UHMWPE).

The layer of sintered porous material may be formed from particles of a first polymer and particles of a second polymer. The first polymer may be selected from the group consisting of: polyethylene, polypropylene, polyester, polycarbonate,

polyvinylidene fluoride, polytetrafluoroethylene, polyethersulfone, polystyrene, polyether imide, polyetheretherketone, polysulfone, and a combination thereof. The second polymer may comprise a thermoplastic elastomer selected from the group consisting of: thermoplastic polyurethane, polyisobutylene, polybutene, polyethylene-propylene copolymer, polyethylene-butene copolymer, polyethylene-octene copolymer,

polyethylene-hexene copolymer, chlorinated polyethylene, chloro-sulfonated

polyethylene, styrene-ethylene-butadiene-styrene, multiblock copolymers having a polyurethane and either a polyester or polyether, 1 ,3-dienes, and a combination thereof.

The layer of sintered porous material may comprise a reticulated structure having a mean porosity between approximately 20 and 80%. In some preferred embodiments, the layer of sintered porous material may comprise a rigidity according to ASTM D747 of less than about 15 pounds. The woven fabric may comprise unsupported or scrim- supported woven fibers. In some preferred embodiments, the web of bonding material may comprise a polymer such as polyamide, polyester, elastomeric, urethane, olefin polymer, and/or a composite or combination thereof (for example, a sheer polyolefin sheet). The step of joining the woven fabric with the web of bonding material may be performed using a fusing belt laminator. In some embodiments, the step of laminating a first laminate with a layer of sintered porous material may be performed using a fusing belt laminator.

Moreover, hybrid filter media manufactured by the aforementioned method is also envisaged. The hybrid filter media is preferably provided in the form of a belt or continuous loop, without limitation. Embodiments of the hybrid filter media may comprise a layer of woven fabric, a layer of sintered porous material, and a web of bonding material between the layer of woven fabric and the layer of sintered porous material. The woven fabric may be bonded to the web of bonding material, and the layer of sintered porous material may also be bonded to the web of bonding material. The hybrid filter media may be configured to withstand harsh industrial pressure filtration environments, resist delamination, and/or be used on large industrial filtration devices.

The layer of woven fabric may comprise unsupported or scrim-supported woven fibers, the layer of sintered porous material may comprise sintered polymeric particles, and the web of bonding material may comprise a sheer polymeric sheet. Polymeric particles used to form the sintered porous material may comprise one or more of the following: polyethylene, polypropylene, polytetrafluoroethylene, polyvinylidene fluoride, ethyl vinyl acetate, polycarbonate, polycarbonate alloy, Nylon 6, thermoplastic polyurethane, polyethersulfone, polyethylene-polypropylene copolymer, and/or a composite thereof. The sintered polymeric particles may comprise high-density polyethylene (HDPE) or ultra-high molecular weight polyethylene (UHMWPE).

The sheer polymeric sheet may comprise a polyamide, polyester, elastomeric, urethane, olefin polymer, and/or a composite thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

To complement the description which is being made, and for the purpose of aiding to better understand the features of the invention, a set of drawings illustrating preferred hybrid filtration media embodiments and methods of making such filtration media is attached to the present specification as an integral part thereof, in which the following has been depicted with an illustrative and non-limiting character. It should be understood that like reference numbers used in the drawings may identify like components.

Figure 1 is a schematic illustrating a first exemplary embodiment of a method of making hybrid filter media.

Figures 2A and 2B are schematics illustrating first and second steps of a second exemplary embodiment of a method of making hybrid filter media, respectively. Figure 3 is an enlarged fragmentary view of a sintered porous polymeric material used in the making of hybrid filter media according to some embodiments.

Figure 4 is an enlarged fragmentary view of an exemplary web of bonding material illustrating exemplary strands that can form an exemplary sheet according to some embodiments.

Figure 5 is an enlarged view of fibers forming the woven fabric material used in the making of hybrid filter media according to some embodiments.

Figure 6 is a flow chart illustrating an exemplary method of forming an

embodiment of hybrid filter media.

Figure 7 is a perspective view of an FLSMIDTFI® PNEUMAPRESS® automatic pressure filter incorporating hybrid filter media according to some embodiments of the invention.

Figure 8 is a side cutaway view of an FLSMIDTFI® PNEUMAPRESS® automatic pressure filter incorporating hybrid filter media according to some embodiments of the invention.

Figures 9 and 10 show an exemplary method of manufacturing hybrid filter media using a fusing belt laminator.

In the following, the invention will be described in more detail with reference to drawings in conjunction with exemplary embodiments. DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

Referring to Figures 1 -2B, hybrid filter media 170 may be created for use in filtration operations involving one or more types of slurries, such as slurries that include a liquid and particulates such as ferrous and non-ferrous minerals, pigments, municipal wastewater sludge/solids, and/or food elements such as corn starch. It is contemplated that embodiments of the hybrid filter media 170 may also be utilized to filter a gas such as air having solid particles entrained therein. It should be understood that the hybrid filter media may be used to physically block the solid particulates from passing therethrough to separate solid particulates from the fluid in which those solid

particulates are entrained.

A hybrid filter media forming apparatus may be utilized to form the hybrid filter media 70. According to a first method 1 , a hybrid filter media forming apparatus may include an upper first roller 40, a lower first roller 42, an upper second roller 50, and a lower second roller 52. A layer of woven fabric 110 may be pre-attached to a web of bonding material 120 by passing the layer of woven fabric 110 and the web of bonding material 120 between the upper first roller 40 and lower first roller 42. The resulting first laminate 160 may then be passed between the upper second roller 50 and lower second roller 52 with a layer of sintered porous material 130, wherein the layer of sintered porous material 130 may be joined to the first laminate 160 at a side facing the web of bonding material 120. The resulting hybrid filter media 170 may be removed and packaged (e.g., on a roll) for subsequent assembly and/or manufacture.

According to a second method 100 comprising a first step 100A and a second step 100B, alternative filter media-forming apparatus may be utilized to form the hybrid filter media 170. During the first step 10OA, a layer of woven fabric 110 may be pre- attached to a web of bonding material 120 by passing the layer of woven fabric 110 and the web of bonding material 120 between an upper first roller 40 and a lower first roller 42 of a first filter media forming apparatus. The resulting first laminate 160 may then be moved to a second filter media forming apparatus. During the second step 100B, the first laminate 160 may be passed between an upper second roller 50 and a lower second roller 52 with a layer of sintered porous material 130. The layer of sintered porous material 130 is preferably joined to the first laminate 160 at the side facing the web of bonding material 120. The resulting hybrid filter media 170 may be removed and packaged (e.g., on a roll) for subsequent assembly and/or manufacture. The resulting hybrid filter media 170 may be cut in sections, and ends connected, joined, and/or spliced (e.g., in order to form a belt or continuous loop of hybrid filter media 170). In some embodiments (not shown), second step 100B may re-utilize upper 40 and lower 42 rollers to join the first laminate 160 and the sintered porous layer 130 in lieu of upper 50 and lower 52 second rollers.

In some embodiments, the woven fibers are preferably of the polymeric type and may comprise one or more types of polymeric fibers. However, the woven fibers may, in some embodiments, comprise on or more organic or naturally-occurring fibrous materials such as cotton, hemp, or other organic material, without limitation. Fibers may include homogeneous monofilament, bi-component, or tri-component fibers. The bi- and tri-component fibers may comprise different materials, without limitation. Multiple different types of monofilament fibers may also be incorporated into the woven fabric 110, without limitation. In some embodiments, bi-component fibers having a core and sheath structure may be used in the woven fibers used in the layer of woven fabric 110, without limitation. It should be understood that various mixtures of fiber types within the layer of woven fabric 110 are anticipated by the inventor.

Fibers used in the layer of woven fabric 110 may comprise homopolymer acrylic, meta aramid, polyethylene (PE, HDPE, LDPE, UHMWPE), polyester (PET), polyimide (PI), polypropylene (PP), polyphenylene sulfide (PPS), polytetrafluoroethylene (PTFE), and/or a combination thereof, without limitation. In some embodiments, fibers used in the layer of woven fabric 110 may comprise two of the aforementioned materials (e.g., high-density polyethylene (FIDPE) and polypropylene), without limitation. Fibers used in the layer of woven fabric 110 may comprise a first material coated with a second material, without limitation. Woven fabric 110 may comprise a series of similar bi- component fibers, each fiber having a core, a sheath, and a number of voids between adjacent fibers, without limitation.

In some embodiments, the adhesive web 120 is preferably comprised of a sheer sheet of randomly-arranged polymeric strands. The polymeric strands may be formed of a monomer and/or a copolymer, and the sheer sheet of polymeric strands may comprise a single type of polymeric strands, or may comprise an assortment of different types of polymeric strands. Any one or more of the polymeric strands may comprise, without limitation, a polyamide fiber, a polyester fiber, an elastomeric fiber, a urethane fiber, an olefin polymer fiber, or a fiber comprising a combination of the aforementioned materials. In some more preferred instances, SPUNFAB® brand adhesive webs may be utilized. Other types of adhesive webs may be used, such as any one or more combinations of products disclosed in W003064153, WO05097482, or W006096170, without limitation.

As shown in FIG. 4, a web of bonding material 120 may comprise a number of strands 126 forming a sheer sheet. In some embodiments, an adhesive web of bonding material 120 may be provided in sheets which are nearly negligible in thickness (e.g., 0.1 -1 mil thick), and weigh between 1 gram and 0.5 ounces per square yard of material, without limitation.

The layer of sintered porous material 130 may, in some preferred embodiments, be comprised of a plurality of particles which have been sintered together. As shown in FIG. 3, particles which have been sintered to form the layer of sintered porous material 130 may form a series of pores or voids 134 between fenestrations 132 - thereby providing the layer of sintered porous material 130 with some amount of porosity and flexibility. The sintered particles may comprise any number of polymeric materials which demonstrate one or more advantageous chemical and mechanical properties (e.g., such as resistance to wear, resistance to solvents, increased flexibility, and low friction coefficients). For example, the sintered particles may, in some instances, comprise a combination of one or more elastomers and one or more plastics (e.g., at least one plastic particle and a plurality of different elastomeric particles, or, a plurality of different types of plastic particles and at least one type of elastomeric particle).

In certain embodiments, elastomers may make up between about 10 and 90 wt.% of the layer 30 of sintered porous material. For example, approximately 20-80 wt.% , 30-70 wt.% , or 40-60 wt.% of the layer of sintered porous material 130 may comprise elastomeric particles. In some non-limiting embodiments, approximately 50 wt.% of the layer of sintered porous material 130 may comprise elastomeric particles. Particles which are sintered to form the layer of sintered porous materia! 130 may be uniform or randomized in shape. Moreover, a size distribution of particles which are sintered may be uniform or randomized throughout portions of or the entire layer 130. In instances where a particle size distribution increases or decreases along a width of the layer of sintered porous material 130, a "functionally-graded" layer may be provided having gradient porosity functionality (e.g., a reduced porosity in area towards the web 120 and fibrous woven material 110, and an increased porosity in areas of the layer 130 further from the web 120 and fibrous woven material 110).

Particles which are sintered to form the layer of sintered porous materia! 130 may each comprise a single homogeneous material, multiple types of materials, or one or more composite materials. For instance, a sintered particle within the layer of porous material 130 may comprise one or more monomers, polymers, plastics, elastomers and/or combinations thereof in a predetermined ratio. The layer 130 may take any desired shape or form such as sheet or a film, or may be crafted from a block of sintered porous material which has been "sliced" into one or more thin sheets or films.

In some particular embodiments, a layer of sintered porous material may be fabricated thinly, so as to exhibit improved flexibility and be configured to be laminated and/or joined to a layer of woven fabric 110 via an adhesive web 120. In some embodiments, the layer of sintered porous material 130 may be formed by fusing multiple layers of sintered porous material together.

Plastics, where used herein, may include flexible plastics and rigid plastics, without limitation, and may include polyolefins, polyamides, polyesters, rigid polyurethanes, polyacrylonitriles, polycarbonates, polyvinylchloride,

polymethylmethacrylate, polyvinylidene fluoride, poiytetrafluoroethylene,

polyethersulfones, polystyrenes, polyether imides, polyetheretherketones, polysulfones, and combinations/copolymers thereof. In some preferred embodiments, a polyolefin plastic may be selected as a material used in the layer of sintered porous material 130. The polyolefin may comprise polyethylene, polypropylene, and/or copolymers thereof.

In some embodiments, polyethylene may be utilized, which may comprise high density polyethylene (HOPE) having a density ranging from about 0.92 g/cm³ to about 0.97 g/cm³ or a degree of crystallinity (% from density) ranging from about 50 to about 90, without limitation. In other embodiments, polyethylene utilized in the layer of sintered porous material 130 may comprise uitrahigh molecular weight polyethylene (UHMWPE) having molecular weights greater than 1 ,000,000.

In addition to at least one plastic, some of the sintered polymeric materials provided within the layer of sintered porous material 130 may comprise at least one elastomer such as a thermoplastic elastomer (TPE) like polyurethane or thermoplastic polyurethane (TPU). Thermoplastic polyurethanes may include multi-block copolymers comprising polyester or polyether, and polyurethane. In other embodiments, elastomers used to form the layer of sintered porous material 130 may comprise, without limitation, polyisobutylene, poiybutenes, butyl rubber, and/or combinations thereof. In further embodiments, elastomers may comprise copolymers of ethylene and other polymers such as polyethylene-propylene copolymer (EPM), ethylene-butene copolymer, polyethylene-octene copolymer, and polyethylene-hexene copolymer. In a further embodiment, elastomers may comprise chlorinated polyethylene or chloro-sulfonated polyethylene.

In some embodiments, elastomers suitable for use in the layer of sintered porous material 130 of the present invention may comprise 1 ,3-dienes and derivatives thereof. 1 ,3-dienes include styrene~1 ,3-butadiene (SBR), styrene-1 ,3-butadiene terpolymer with an unsaturated carboxylic acid (carboxy!ated SBR), acrylonitrile-1 ,3-butadiene (NBR or nitrile rubber), isobutylene-isoprene, cis-1 ,4-polyisoprene, 1 ,4-po!y(1 ,3-butadiene), polychioroprene, and block copolymers of isoprene or 1 ,3-butadiene with styrene such as styrene-ethylene-butadiene-styrene (SEBS) may also be utilized. In other embodiments, elastomers may comprise polyalkene oxide polymers, acrylics, or polysiloxanes (silicones), and/or combinations thereof.

Examples of commercially-available elastomers suitable for use in the layer of sintered porous material 130 may include FORPRENE®, LAPRENE®, SKYPEL®,

SKY THANE®, SYNPRENE®, RIMFLEX®, E!exar, FLEXALLOY®, TEKRON®,

DEXFLEX®, Typlax, Uceflex, ENGAGE®, HERCUPRENE®, Hi-fax, Nova!ene, Kraton, Muti-Flex, EVGPRENE®, HYTREL®, NORDEL®, VITON®, Vector, SILASTIC®, Santoprene, Elasmax, Affinity, ATTANE®, and SARLINK®, without limitation.

Porosity in the layer of sintered porous material 130 may range from about 10% to about 90%. For example, in some embodiments, the layer of sintered porous material 130 may comprise at least one plastic and at least one elastomer and have a porosity ranging from about 20% to about 80% (e.g., between about 30% and about 70%) In further embodiments, a layer of sintered porous material 130 may comprise at least one plastic and at least one elastomer and have a porosity ranging between approximately 40% and 60% (e.g , 50% open space).

In some preferred embodiments, the layer of sintered porous material may comprise micro porosities or regions of varying porosity throughout the layer. In some instances, the layer of sintered porous material 130 may comprise an average pore size ranging from about 1 pm to about 200 pm. For example, in some non limiting

embodiments, pore size may be between about 2 pm and 150 pm, between about 5 pm and 100 pm, or between about 10 pm and 50 pm). In some embodiments, the layer 130 of sintered porous material may comprise an average pore size of less than about 1 pm (e.g., about 0.1 -1 pm). In further embodiments, pore sizes may exceed 200 pm. In some particular non-limiting embodiments, sintered porous material 130 comprising at least one plastic and at least one elastomer may have an average pore size ranging from about 200 pm to about 500 pm or from about 500 pm to about 1 mm.

The layer of sintered porous material 130 may have a density between

approximately 0 1 g/cm³ and 1 g/cm⁵, and more particularly between approximately 0.2 g/cm⁵ and 0.8 g/cm³ In some instances, density of the layer of sintered porous material 130 may fall between 0.4 and 0.6 g/cm³ (e.g., about 0.5g/cm⁵). In further embodiments, a layer of sintered porous material may comprise at least one plastic and at least one elastomer and may exhibit a density greater than about 1 g/cm³. In yet even further embodiments, the layer of sintered porous material 130 may have a density less than about 0.1 g/cm³. Sintered porous materials described herein may further comprise a rigidity according to ASTM D747 (i.e. , "Standard Test Method for Apparent Bending Modulus of Plastics by Means of a Cantilever Beam") of less than about 15 pounds, for example, less than about 10 pounds. In some embodiments, a rigidity of the layer of sintered porous materia! 130 may be less than about 5 pounds, for example, less than about 1 pound. Tensile strength of the layer of sintered porous material 30 may range from about 10 to about 5,000 psi as measured according to ASTM D838. For example, in some embodiments, the tensile strength may fail within the range of about 50 to 3000 psi or between 100 and 1 ,000 psi as measured according to ASTM D638. In some embodiments, a layer of sintered porous material 130 comprising at least one plastic particle sintered with at least one elastomeric particle may have an elongation of 10% to 500%. In some embodiments, the layer of sintered porous material 130 may be provided in thicknesses less than 1/4", and above 1/16", for example around 1/8" or around 0.07 to 0.09 inches.

In use, filtration solids are stopped, held, or hindered by the layer of sintered porous material 130. Voids 134 within the sintered porous material 130 may be configured to prevent migration of the filtration solids from penetrating through the layer 130, as well as to prevent, slow, or hinder migration of filtration solids through

subsequent layers (i.e., fibrous material 110 and/or bonding web 120). The rigidity and toughness of the layer of sintered porous material 130 may further help to prevent solids (which may get trapped in voids 134) from experiencing micro-motion and wear therefrom commonly seen with conventional woven cloth filter media.

The web of bonding material 120 serves to prevent delamination of the layer of sintered porous material 130 from the layer of woven fabric 110 as the hybrid filter media 170 traverses sharp corners, small pulleys, and experiences high tensile and shear forces during filter operations and/or during initial fitment to a filtering apparatus. Material for sheaths of bi-component fibers, if used within the woven fabric 110, may be chosen to be most compatible with the material of the web 120 and/or the sintered porous material 130 in order to further mitigate the risk of delamination.

Turning to FIG. 6, an embodiment for a method 300 of manufacturing hybrid filter media is shown. The exemplary method 300 comprises the steps of: providing a woven fabric material 302, providing a web of bonding material 304, pre-attaching 306 the web to the woven fabric material to form a first laminate, providing 308 a sheet of sintered porous material, and laminating 310 the sintered porous material to the first laminate, without limitation. Additional steps and/or variations of the aforementioned steps are anticipated.

FIGS. 7 and 8 depict pressure filter machines (e.g., pneumatic automatic pressure filters) on which embodiments of the hybrid filter media disclosed herein may be advantageously utilized, in particular, for starch filtration. It should be understood that embodiments of the hybrid filter media disclosed herein may also be utilized on devices which are not shown, and that the filtering devices described herein are non- exhaustive applications of the hybrid filter media disclosed herein. FIG. 7 is a is a perspective view of a PNEUMAPRESS® automatic pressure filter 400 incorporating hybrid filter media 170 according to an embodiment of the invention. FIG. 8 is a side cut away view of the embodiment shown in FIG. 7. The hybrid filter media 170 for an automatic pressure filter 170 may be provided as a plurality of smaller individual belts for individual filtration modules (e.g., PNEUMAPRESS® stacked filters).

Figures 9 and 10 are schematic illustrations which collectively show a third method 1000 of manufacturing hybrid filter media 170 using a fusing belt laminator according to some embodiments. The third method 1000 may comprise a first step 1000A and a second step 1000B. The first step 1000A may comprise joining a woven fabric 110 with a web of bonding material 120 with a fusing belt laminator. As the woven fabric 110 and web of bonding material 120 are heated and then pressed between an upper belt 80 and a lower belt 90, they are mechanically joined. The resulting composite first laminate 160 may be cooled while still under pressure between the upper 80 and lower 90 belts as shown.

Upper 80 and lower 90 belts may be supported by upper 40 and lower 42 first rollers; upper 50 and lower 52 second rollers; and upper 60 and lower 62 third rollers and may be spaced to create equally uniform or progressive height of compression gap spacings between belts 80, 90. After the first step 1000A is completed, the first laminate 160 may be subsequently joined with a layer of sintered porous material 130 in a second step 1000B. The second step 1000B may comprise laminating the first laminate 160 with a layer of sintered porous material 130, wherein the web of bonding material 120 of the first laminate 160 is most adjacent to the layer of sintered porous material 130. The resulting laminate may comprise a final or intermediate hybrid filter media 170 product.

It should be appreciated that a contractor or other entity may provide a hybrid filter media, manufacturing apparatus for making hybrid filter media, or operate a manufacturing apparatus in whole, or in part, as shown and described. For instance, the contractor may receive a bid request for a project related to designing hybrid filter media or operating an apparatus for making hybrid filter media, or the contractor may offer to design such a hybrid filter media system or a process for a client. The contractor may then provide, for example, any one or more of the devices or features thereof shown and/or described in the embodiments discussed above.

The contractor may provide such devices by selling those devices or by offering to sell those devices. The contractor may provide various embodiments that are sized, shaped, and/or otherwise configured to meet the design criteria of a particular client or customer. The contractor may select various materials which are able to meet the design criteria of a particular client or customer. The contractor may subcontract the fabrication, delivery, sale, or installation of a component of the devices disclosed, or of other devices used to provide or manufacture said devices.

The contractor may also survey a site and design or designate one or more storage areas for stacking the material used to manufacture the devices, or for storing the devices and/or components thereof. The contractor may also maintain, modify, or upgrade the provided devices. The contractor may provide such maintenance or modifications by subcontracting such services or by directly providing those services or components needed for said maintenance or modifications, and in some cases, the contractor may modify a preexisting pressure filter or other manufacturing apparatus, or parts thereof with a“retrofit kit” to arrive at a modified apparatus comprising one or more method steps, devices, components, or features of the systems and processes discussed herein.

Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. For example, it is contemplated that a particular feature described, either individually or as part of an embodiment, can be combined with other individually described features, or parts of other embodiments.

The elements and acts of the various embodiments described herein can therefore be combined to provide further embodiments. While certain embodiments of the invention incorporate a layer of sintered porous material having a mean pore size which is generally between 10 and 20 micrometers, it may be possible to have nominal pore size values ranging between 5 and 150 micrometers, and even up to 300 micrometers, depending on which materials are used. In some embodiments, the woven fabric may comprise homogenous fiber materials and/or blends of fiber materials. In some embodiments, the sintered porous material comprises ultra-high molecular weight polyethylene (UHMWPE). Porous sintered material disclosed herein may comprise, without limitation, one or more types of polyethylene, including low density-types (LDPE), high density types (HDPE), and ultra- high molecular weight types (UHMWPE). While certain present preferred embodiments of a hybrid filtration media, an apparatus for making filtration media and methods of making and using the same have been shown and described above, it is to be distinctly understood that the invention is not limited thereto but may be otherwise variously embodied and practiced within the scope of the following claims. REFERENCE NUMERAL IDENTIFIERS

1 first method

100 second method

100A first step 100B second step

1000 third method

1000A first step

1000B second step

40 upper first roller

42 lower first roller

50 upper second roller

52 lower second roller

60 upper third roller

62 lower third roller

80 upper belt

90 lower belt

1 10 woven fabric

120 web of bonding material

126 strand

130 sintered porous material

132 fenestration

134 pore

160 first laminate

170 hybrid filter media

400 automatic pressure filter

Claims

What is claimed is: 1. A method of making hybrid filter media [170] for large industrial filtration devices comprising:

providing a layer of woven fabric [110];

providing a web of bonding material [120];

providing a layer of sintered porous material [130];

joining the layer of woven fabric [110] with the web of bonding material [20]; and joining the layer of sintered porous material [130] to the web of bonding material

[120]

2. The method of claim 1 , wherein the step of joining the layer of woven fabric

[110] with the web of bonding material [120] comprises a laminating step to form a first laminate [160]

3. The method of claim 2, wherein the step of joining the layer of sintered porous material [30] to the web of bonding material [120] comprises laminating the first laminate [160] with the layer of sintered porous material [130]

4. The method of claim 1 , wherein the step of joining the layer of sintered porous material [130] to the web of bonding material [120] occurs after the step of joining the layer of woven fabric [110] with the web of bonding material [120] 5. The method of claim 1 , wherein the layer of sintered porous material [130] comprises at least one polymer.

6. The method of claim 5, wherein the at least one polymer comprises at least one of: polyethylene, polypropylene, polyester, polycarbonate, polyvinylidene fluoride, polytetrafluoroethylene, polyvinylidene fluoride, ethyl vinyl acetate, polycarbonate, polycarbonate alloy, nylon 6, thermoplastic polyurethane (TPU), polyethersulfone (PES), and polyethylene-polypropylene copolymer.

7. The method of claim 6, wherein the at least one polymer comprises high- density polyethylene (HDPE) or ultra-high molecular weight polyethylene (UHMWPE).

8. The method of claim 5, wherein the layer of sintered porous material [130] comprises particles of a first polymer and particles of a second polymer; wherein said first polymer is selected from the group consisting of: polyethylene, polypropylene, polyesters, polycarbonates, polyvinylidene fluoride, polytetrafluoroethylene, polyethersulfones, polystyrenes, polyether imides, polyetheretherketones, polysulfones, and combinations thereof; and, wherein said second polymer comprises a thermoplastic elastomer selected from the group consisting of: thermoplastic polyurethanes, polyisobutylene, polybutenes, polyethylene-propylene copolymer, polyethylene-butene copolymer, polyethy!ene- octene copolymer, polyethylene-hexene copolymer, chlorinated polyethylene, chloro- sulfonated polyethylene, styrene-ethylene-butadiene-styrene, multiblock copolymers having a polyurethane and either a polyester or polyether, 1 ,3-dienes, and combinations thereof.

9. The method of claim 1 , wherein the layer of sintered porous material [130] comprises a reticulated structure having a mean porosity between approximately 20% and 80%. 10. The method of claim 1 , wherein the layer of sintered porous material [130] comprises a rigidity according to ASTM D747 of less than about 15 pounds.

11. The method of claim 1 , wherein the woven fabric [110] comprises

unsupported or scrim-supported woven fibers.

12. The method of claim 1 , wherein the web of bonding material [120] comprises a polymer.

13. The method of claim 12, wherein the polymer comprises a polyamide, polyester, an elastomeric, a urethane, an olefin polymer, or a composite thereof. 14. The method of claim 13, wherein the polymer comprises a sheer polyolefin sheet.

15. The method of claim 1 , wherein the step of joining the woven fabric [110] with the web of bonding material [120] is performed using a fusing belt laminator.

16. The method of claim 3, wherein the step of laminating the first laminate [160] with the layer of sintered porous material [130] is performed using a fusing belt laminator. 17. Hybrid filter media [170] manufactured by the method of claim 1.

18. Hybrid filter media [170] comprising:

a layer of woven fabric [110];

a layer of sintered porous material [130]; and,

a web of bonding material [120] between the layer of woven fabric [110] and the layer of sintered porous material [130];

wherein the woven fabric [110] is bonded to the web of bonding material [120]; wherein the layer of sintered porous material [130] is bonded to the web of bonding material [120]; and wherein the hybrid filter media [170] is configured to withstand harsh industrial vacuum filtration environments, resist delamination, and be used on large industrial filtration devices. 19. The hybrid filter media [170] of claim 18, wherein the layer of woven fabric

[110] comprises polymeric fibers; wherein the layer of sintered porous material [130] comprises a sintered polymeric particles; and, wherein the web of bonding material [120] comprises a sheer polymeric sheet. 20. The hybrid filter media of claim 19, wherein the polymeric particles comprise one or more of the following: polyethylene, polypropylene, polytetrafluoroethylene, polyvinylidene fluoride, ethyl vinyl acetate, polycarbonate, polycarbonate alloy, nylon 6, thermoplastic polyurethane, polyethersulfone, polyethylene-polypropylene copolymer, and composites thereof

21. The hybrid filter media [170] of claim 19, wherein the polymeric fibers are scrim-supported.

22. The hybrid filter media [170] of claim 19, wherein the sintered polymeric particles comprise high-density polyethylene (HDPE) or ultra-high molecular weight polyethylene (UHMWPE).

23. The hybrid filter media [170] of claim 19, wherein the sheer polymeric sheet comprises a polyamide, polyester, an elastomeric, a urethane, an olefin polymer, or a composite thereof.