WO2022034442A1

WO2022034442A1 - Multilayer filter assembly

Info

Publication number: WO2022034442A1
Application number: PCT/IB2021/057160
Authority: WO
Inventors: John F. Reed; John B. STENDER; Matthew W. Gorrell; Martin J. O. WIDENBRANT; Byron E. Trotter
Original assignee: 3M Innovative Properties Company
Priority date: 2020-08-10
Filing date: 2021-08-04
Publication date: 2022-02-17

Abstract

A multilayer filter stack is disclosed. The multilayer filter stack includes a first filter layer defining a first side and an opposed second side and a second filter layer defining a first side and an opposed second side. The second filter layer is disposed adjacent the first filter layer. A connector releasably secures the first filter layer to the multilayer filter stack and the first filter layer is adapted to be removable from the multilayer filter stack.

Description

Multilayer Filter Assembly

Background

Filters are used for many purposes, such as removing small suspended particulates from fluid flows. Filtration systems can include multiple layers attached via different releasably- joining technologies.

Summary

In some aspects, a multilayer filter stack is disclosed. The multilayer filter stack can include a first filter layer defining a first side and an opposed second side, and a second filter layer defining a first side and an opposed second side. The second filter layer can be disposed adjacent the first filter layer. A connector can releasably secure the first filter layer to the multilayer filter stack. The first filter layer can be adapted to be removable from the multilayer filter stack.

In some aspects, a method for forming a multilayer filter stack is disclosed. The method can include providing a multilayer filter roll, the multilayer filter roll including a first filter layer, a second filter layer and a connector releasably securing the first filter layer to the second filter layer. The method can further include unrolling at least a portion of the multilayer filter roll and separating the portion of the multilayer filter roll from the remainder of the multilayer filter roll to form the multilayer filter stack.

Brief Description of the Drawings

FIG. 1 is schematic system view of a filtration system including cooking equipment and an exhaust system according to exemplary embodiments of the present disclosure.

FIGS. 2-4 are schematic side elevation views of a multilayer filter stack showing layers and connectors according to exemplary embodiments of the present disclosure.

FIG. 5 is a top plan view of the multilayer filter stack of FIG. 4 showing layers and connectors according to exemplary embodiments of the present disclosure.

FIGS. 6-7 are schematic side views of another embodiment of a multilayer filter stack showing layers and connectors according to exemplary embodiments of the present disclosure.

FIG. 8 is an exploded side elevation view of a multilayer filter stack according to exemplary embodiments of the present disclosure.

FIG. 9 is a top plan view of the multilayer filter stack of FIG. 7 showing layers and connectors according to exemplary embodiments of the present disclosure. FIGS. 10-11 are schematic side views of another embodiment of a multilayer filter stack showing layers and connectors according to exemplary embodiments of the present disclosure.

FIG. 12 is a perspective view of a multilayer filter roll, also showing a portion of unrolled material, according to exemplary embodiments of the present disclosure.

Detailed Description

In the following description, reference is made to the accompanying drawings that form a part hereof and in which various embodiments are shown by way of illustration. The drawings are not necessarily to scale. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present description. The following detailed description, therefore, is not to be taken in a limiting sense.

Filters can be used in a wide range of applications. In some embodiments, filters may be designed for general air filtration to filter primarily airborne particulates. For example, filters may be designed to filter particles smaller than 10 micrometers in diameter, smaller than 5 micrometers in diameter, smaller than 2.5 micrometers in diameter, smaller than 1.0 micrometer in diameter, smaller than 0.5 micrometers in diameter or smaller than 0.3 micrometers in diameter, among others.

Filters can also be used in a specific location, such as an exhaust hood, for grease filtering in a commercial cooking environment. In commercial kitchens, grease capture in exhaust hoods may be important for health, safety and environmental reasons. However, grease buildup in and around an exhaust hood or an exhaust system may pose a fire hazard. To mitigate the hazard, commercial kitchens typically use airflow interrupters or disrupters, such as baffles. These can be made of a non-flammable material, such as a metal or metal alloy, including stainless steel, galvanized steel or aluminum. The baffle can prevent fire from spreading from the cooking surface into the exhaust system.

However, grease buildup on baffles requires regular cleaning to maintain the baffle’s effectiveness as a fire barrier and a grease collector. Aesthetically, visible grease on a commercial hood baffle can also be undesirable. Removing, cleaning and reinstalling the baffles can be time consuming, labor-intensive, expensive and dangerous. The present disclosure provides various embodiments of an improved filtration system and filter, particularly a multi-layer filter. Versus conventional baffles, the present disclosure can provide a low-cost grease-trapping solution that is lightweight and easy to install in an exhaust hood. Portions of the disclosed filtration system (or the stack) can occupy a range hood position traditionally occupied by conventional baffles. Elements of the disclosed filtration system can also augment traditional baffles in an exhaust hood, thereby requiring minimal or no modifications to existing exhaust systems. Other benefits and uses are also foreseen. For clarity, moving from the cooking equipment through the exhaust system and past the blower can be defined as moving downstream, while moving in the opposite direction can be defined as moving upstream.

FIG. 1 is a schematic sectional view of a filtration system 40 including cooking equipment 50 and an exhaust system 54. The cooking equipment 50 can be an oven, stove, grill, fryer, broiler or any other commonly used cooking apparatus known to those skilled in the art and can further define a cooking surface 52. The exhaust system 54 can include an exhaust hood 58 defining an exhaust hood flange 60. The exhaust hood flange 60, can releasably or permanently retain a baffle and/or a filter. An exhaust hood intake 59 can be defined by the exhaust hood 58, and can represent an upstream portion of the exhaust hood 58 and/or a portion of the exhaust hood 58 into which gasses or fluid flows enter the exhaust hood 58. The exhaust hood 58 can be positioned to capture all or a portion of grease and other particulates generated by the use of the cooking equipment 50. A blower 66 can, via a duct 62, create a reduced-pressure area proximate the cooking equipment 50 (relative to ambient pressure) that can encourage grease and other particulates generated by use of the cooking equipment 50 to enter the exhaust system 54 via the exhaust hood 58. In such a system, as illustrated in FIG. 1 , air, gasses, grease and/or particulates can travel into the exhaust system 54 via the exhaust hood 58 and multilayer filter stack 100, as represented by arrow 70. The filtered air, gasses and any remaining grease and/or particulates can then pass through the duct 62 and blower 66 before exiting the exhaust system 54, as represented by arrow 74. Arrows 70 and 74 represent portions of a fluid flow traveling from the cooking surface 52, through the exhaust hood 58 and out through the rest of the exhaust system 54.

Turning to FIGS. 2-5, a multilayer filter stack 100 is shown in various embodiments. The multilayer filter stack 100 can include a first filter layer 104 defining a first side 108 and second side 112 disposed opposite the first side 108. In some embodiments, the first side 108 can be facing in a substantially upstream direction in an exhaust system 54 (as exemplarily shown in FIG. 1) or a fluid flow, and the second side 112 can be facing in a substantially downstream direction in an exhaust system 54 or a fluid flow. As can be seen in FIG. 5, a perimeter 116 of the first filter layer 104 can be seen from a top-elevation perspective.

The multilayer filter stack 100 can further include a second filter layer 120 defining a first side 124 and second side 128 disposed opposite the first side 124. In some embodiments, the first side 124 can be facing in a substantially upstream direction in an exhaust system 54 or a fluid flow, and the second side 128 can be facing in a substantially downstream direction in an exhaust system 54 or a fluid flow. As can be seen in FIG. 5, a perimeter 132 of the second filter layer 120 can be seen from a top-elevation perspective.

The multilayer filter stack 100 can also include a third filter layer 150 defining a first side 154 and second side 158 disposed opposite the first side 154. In some embodiments, the first side 154 can be facing a substantially upstream direction in an exhaust system 54 or a fluid flow, and the second side 158 can be facing a substantially downstream direction in an exhaust system 54 or a fluid flow. As can be seen in FIG. 5, a perimeter 159 of the third filter layer 150 can be seen from a top-elevation perspective.

The multilayer filter stack 100 can include a connector 140, or a first connector, and a connector 160, or a second connector. The connector 140 can releasably connect with the connector 160 to releasably connect the first layer 104 to the second layer 120. The connector 140 can releasably connect with the connector 160 to releasably connect the third layer 150 to the second layer 120. In some embodiments, the connector 140 can releasably connect with the connector 160 to releasably connect the first layer 104 to the stack 100. In some embodiments, the connector 140 can releasably connect with the connector 160 to releasably connect the second layer 120 to the stack 100. In some embodiments, the connector 140 can releasably connect with the connector 160 to releasably connect the third layer 150 to the stack 100.

The connector 140 can be disposed at least partially between the first layer 104 and the second layer 120, as can be seen in FIGS. 2-4. The connector 160 can be disposed at least partially between the third layer 150 and the second layer 120, as can be seen in FIGS. 3 and 4. In some embodiments, the connector 140 can be permanently or releasably attached to the second side 112 of the first layer 104. In some embodiments, the connector 140 can be permanently or releasably attached to the first side 124 of the second layer 120. In some embodiments, the connector 160 can be permanently or releasably attached to the second side 128 of the second layer 120. In some embodiments, the connector 160 can be permanently or releasably attached to the first side 154 of the third layer 150. The connectors 140, 160 and the other connectors described in this specification, will be described below in greater detail.

The connector 140 can be disposed at a perimeter 116 of the first layer 104 and/or at a perimeter 132 of the second layer 120. In some embodiments, the connector 140 can extend outwardly from the perimeter 116 and/or outwardly from the perimeter 132. The connector 160 can be disposed at a perimeter 159 of the third layer 150 and/or at a perimeter 132 of the second layer 120. In some embodiments, the connector 160 can extend outwardly from the perimeter 159 and/or outwardly from the perimeter 132. A perimeter 170 of the multilayer filter stack 100 from a top-elevation perspective can be seen in FIG. 5. In some embodiments, the connector 160 and/or the connector 140 can extend outwardly from the perimeter 170. As best shown in FIGS. 3 and 4, the first layer 104 and the third layer 150 can be disposed at substantially opposite sides of the second layer 120. Further, the first connector 140 and the second connector 160 can be disposed at substantially opposite sides of the second layer 120.

In some embodiments, the connector 140 and the connector 160 are releasably connected to each other at a location outside of the perimeter 116, perimeter 132, perimeter

159 and/or perimeter 170. In some embodiments, the connector 140 and the connector 160 are releasably connected to each other at more than one location outside of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170. In some embodiments, the connector 140 and the connector 160 are releasably connected to each other at multiple locations outside of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170, the multiple locations corresponding with sides of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170.

In some embodiments, as exemplarily illustrated in FIGS. 6-9, the multilayer filter stack 100 can include the connector 140 along with a third connector 180, a fourth connector 184 and a fifth connector 188. The connector 140 can releasably connect with the connector 180 to releasably connect the first layer 104 to the second layer 120. In some embodiments, the connector 140 can releasably connect with the connector 180 to releasably connect the first layer 104 to the stack 100. In some embodiments, the connector 140 can releasably connect with the connector 180 to releasably connect the second layer 120 to the stack 100. The connector 140 and the connector 180 can be disposed at least partially between the first layer 104 and the second layer 120, as can be seen in FIGS. 6-8.

The connector 184 can releasably connect with the connector 188 to releasably connect the third layer 150 to the second layer 120. In some embodiments, the connector 184 can releasably connect with the connector 188 to releasably connect the third layer 150 to the stack 100. In some embodiments, the connector 140 can releasably connect with the connector 180 to releasably connect the second layer 120 to the stack 100. The connector 180 and the connector 188 can be disposed at least partially between the third layer 150 and the second layer 120, as can be seen in FIGS. 6-8.

In some embodiments, the connector 140 can be permanently or releasably attached to the second side 112 of the first layer 104. In some embodiments, the connector 180 can be permanently or releasably attached to the first side 124 of the second layer 120. In some embodiments, the connector 184 can be permanently or releasably attached to the second side 128 of the second layer 120. In some embodiments, the connector 188 can be permanently or releasably attached to the first side 154 of the third layer 150.

The connector 140 can be disposed at the perimeter 116 of the first layer 104, the connector 180 can be disposed at the perimeter 132 of the second layer 120, the connector 184 can be disposed at the perimeter 132 of the second layer 120, and the connector 188 can be disposed at the perimeter 159 of the third layer 150.

In some embodiments, the connector 140 does not extend outwardly from the perimeter 116, 132, 159 and/or 170. In some embodiments, the connector 180 does not extend outwardly from the perimeter 116, 132, 159 and/or 170. In some embodiments, the connector 184 does not extend outwardly from the perimeter 116, 132, 159 and/or 170. In some embodiments, the connector 188 does not extend outwardly from the perimeter 116, 132, 159 and/or 170. In some embodiments, the connector 140 and the connector 180 are releasably connected to each other at a location inside of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170. In some embodiments, the connector 140 and the connector 180 are releasably connected to each other at more than one location inside of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170. In some embodiments, the connector 140 and the connector 180 are releasably connected to each other at multiple locations inside of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170, the multiple locations corresponding with sides of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170.

In some embodiments, the connector 184 and the connector 188 are releasably connected to each other at a location inside of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170. In some embodiments, the connector 184 and the connector 188 are releasably connected to each other at more than one location inside of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170. In some embodiments, the connector 184 and the connector 188 are releasably connected to each other at multiple locations inside of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170, the multiple locations corresponding with sides of the perimeter 116, perimeter 132, perimeter 159 and/or perimeter 170.

In some embodiments, as exemplarily illustrated in FIGS. 10 and 11 , the multilayer filter stack 100 can include the connector 140 that releasably connects the first layer 104 to the second layer 120. In some embodiments, the connector 140 can releasably connect the first layer 104 to the second layer 120 to releasably connect the first layer 104 and/or the second layer 120 to the stack 100. The connector 140 can be disposed at least partially between the first layer 104 and the second layer 120, as can be seen in FIG. 10.

In some embodiments, the connector 140 can be permanently or releasably attached to the second side 112 of the first layer 104. In some embodiments, the connector 140 can be permanently or releasably attached to the first side 124 of the second layer 120. The connector 140 can be disposed at the perimeter 116 of the first layer 104, at the perimeter 170 of the stack 100 and/or at the perimeter 132 of the second layer 120. In some embodiments, the connector 140 does not extend outwardly from the perimeter 116, 132 and/or 170.

In some embodiments, the connector 140 is releasably or permanently connected to the first layer 104 at a location inside of the perimeter 116 and/or perimeter 170. In some embodiments, the connector 140 is releasably or permanently connected to the second layer 120 at a location inside of the perimeter 132 and/or perimeter 170. In some embodiments, the connector 140 releasably connects the first layer 104 and the second layer 120 to each other at more than one location inside of the perimeter 116, perimeter 132 and/or perimeter 170. In some embodiments, the connector 140 releasably connects the first layer 104 and the second layer 120 to each other at multiple locations inside of the perimeter 116, perimeter 132 and/or perimeter 170, the multiple locations corresponding with sides of the perimeter 116, perimeter 132 and/or perimeter 170. Although only two layers 104, 120 and one connector 140 are shown in FIGS. 10 and 11, it is to be understood that any number of layers with a connector between sequential layers in the manner shown in FIGS. 10 and 11 is within the scope of this disclosure.

Turning to FIG. 12, a multilayer filter roll 200 can be seen in a partially-separated state. The multilayer filter roll 200 can be unrolled such that portions of unrolled material 201 can be rolled out from the roll 200 in a similar manner to a paper towel roll. In some embodiments, the material 201 unrolled from the roll 200 as a single body of material can include a plurality of individual layers, as illustrated in FIG. 12. In particular, exemplary layers can include a first filter layer 204 (which can be similar to the first layer 104) and a second filter layer 208 (which can be similar to the second filter layer 120).

A roll connector 210 can be disposed at least partially between the layers 204 and 208. The roll connector 210 can releasably join the first and second layers 204, 208 in any of the arrangements described in this disclosure with respect to releasably connecting layers with connectors. In some embodiments, the roll connector 210 can include two strips disposed along a length of the unrolled material 201 and arranged on substantially opposed sides of the first and second layers 204, 208.

The unrolled material 201 can also include a liner 212. The liner can be disposed on one or both sides of the unrolled material 201. In some embodiments, the liner 212 can be disposed on a side of the second layer 208 opposite from the roll connector 210 and the first layer 204. The liner 212 can include a polymeric material, or any other material known to those skilled in the art, that facilitates the unrolling of the unrolled material 201 from the multilayer filter roll 200. The liner 212 can also physically and/or chemically separate adjacent layers within the multilayer filter roll 200.

A plurality of separation areas 216 can be included in the unrolled material 201 and in the layers 204, 208, roll connector 210 and/or liner 212. The separation areas 216 can include visual markings or physically-weakened features to facilitate the separating of a portion of the unrolled material 201 from the remainder of the unrolled material 201 and the multilayer filter roll 200. Additionally, while shown with two layers and a connector, it is to be understood that the unrolled material 201 can include any number and configuration of connectors and layers as described in this disclosure.

A method for forming a multilayer filter stack 100 is also disclosed. The method can include providing a multilayer filter roll 200. The multilayer filter roll 200 can include a first filter layer 204, a second filter layer 208 and a roll connector 210 for releasably connecting the first filter layer 204 to the second filter layer 208. The method can further include unrolling at least a portion 201 of the multilayer filter roll 200 and separating the portion 201 of the multilayer filter roll from the remainder of the multilayer filter roll 200 to form the multilayer filter stack 100. A liner 212 can be disposed between at least some multilayer rolled layers of the multilayer filter roll 200.

In various embodiments, the layers 104, 120, 150, 204 and/or 208 can include different materials or the same material. In particular, the layers 104, 120, 150, 204 and/or 208 can include fiberglass, steel, stainless steel, aluminum, aluminum foil, perforated aluminum foil, metals, metal alloys, polymers, carbon, ceramics, organic materials, braided materials, fire- resistant materials, 3M NEXTEL Ceramic Fibers and Textiles, cardboard, chip board or any other material known to those skilled in the art.

In some embodiments, the layers 104, 120, 150, 204 and/or 208 can include fibers that form a non-woven and/or non-knitted material. The non-woven and/or non-knitted material can describe materials that are bonded together by chemical, mechanical, heat or solvent treatments, rather than by knitting or weaving. The non-woven material can be lofty, carded, air-laid or mechanically bonded (such as spun-lace, needle-entangled or needle-tacked). The non-woven material can be bonded (e.g., the fibers are bonded to one another at various locations) or non-bonded.

The layers 104, 120, 150, 204 and/or 208 can include a heat-setting material or a melt material that provides some or all of the bonding in the non-woven material, such as a flake, powder, fiber or a combination thereof. The heat-setting material can include any suitable thermoplastic or thermoset polymer, such as polyester, polyethylene terephthalate (PET), polypropylene (PP) or a combination thereof. After melting and/or heat bonding, the flake, powder and/or fiber can melt and bond the fibers together, increasing a strength and stability of the material.

In some embodiments, the layers 104, 120, 150, 204 and/or 208 can include a flameresistant (FR) material, oxidized polyacrylonitrile fiber (OPAN), modacrylic, flame-resistant rayon, polyacrylonitrile (PAN), polyphenylene sulfide (PPS), polyethylene terephthalate (PET), polypropylene (PP), kapok fiber, poly lactic acid (PLA), cotton, nylon, polyester, rayon (e.g., non-flame-retardant rayon), wool, basalt, fiberglass, ceramic or a combination thereof. In some embodiments, the layers 104, 120, 150, 204 and/or 208 can include a conventional filter media material (such as polyolefin) that has been treated or coated to be flame-resistant, a conventional filter media material and a metal mesh and/or a flame-resistant barrier. In some embodiments, the fibers can be bicomponent fibers, or fibers made of more than one material, such as those listed in this disclosure. In various embodiments, the filter media can be pleated, non-pleated and/or multilayered (which can include a multi-layer web including a woven layer, such as a woven basalt layer), based upon application.

The layers 104, 120, 150, 204 and/or 208 can, in various embodiments, include a coating, a heat-setting or melt material (e.g., powder, flakes and/or fibers), a metal fiber, a glass fiber, a ceramic fiber, an aramid fiber, a sorbent, an intumescent material (e.g., a fiber or a particle), mica, diatomaceous earth, glass bubbles, carbon particles or a combination thereof. Examples of flame-resistant materials include any polymer designated as flame-retardant (e.g., as pure materials or as compounds including the materials), aluminum, polyphosphate, phosphorus, nitrogen, sulfur, silicon, antimony, chlorine, bromine, magnesium, zinc, carbon or a combination thereof. Flame-resistant materials can be halogen-containing flame retardants or non-halogenated flame retardants. Examples of coatings or additives can include expandable graphite, vermiculite, ammonium polyphosphate, alumina trihydrate (ATH), magnesium hydroxide (Mg(OH)2), aluminum hydroxide (AI(OH)3), molybdate compounds, chlorinated compounds, brominated compounds, antimony oxides, organophosphorus compounds or a combination thereof.

In some embodiments, the layers 104, 120, 150, 204 and/or 208 can include airlaid nonwoven web prepared using 90% oxidized polyacrylonitrile (OPAN) staple fiber with a denier diameter of 5.0dtex x 60mm (commercially available under the trade designation ZOLTEK OX) and 10% binding fiber (high temperature polyester binding or melty fiber with a denier diameter of 6.7dtex x 60 mm, commercially available under the trade designation TREVI RA T270) with an area weight of 150 grams per square meter.

In some embodiments, the layers 104, 120, 150, 204 and/or 208 can include airlaid nonwoven web prepared using nylon staple fiber with a denier diameter of 1000 dtex, or denier, and 10% binding fiber (commercially available under the trade designation TREVI RA T270) with an area weight of 550 grams per square meter.

In some embodiments, the layers 104, 120, 150, 204 and/or 208 can include airlaid nonwoven web prepared using 40% 5.0dtex x 60 mm OPAN staple fiber, 40% 500 dtex, or denier, PET staple fiber (commercially available from David C. Poole Company, Inc., Greenville, SC), and 20% 15 dtex, or denier, binding fiber, such as is commercially available from Huvis (Seoul, South Korea) with an area weight of 225 grams per square meter.

In various embodiments, the layers 104, 120, 150, 204 and/or 208 can have a constant, substantially constant or variable thickness as measured from a first side (upstream) to a second side (downstream) of the respective layer. In various embodiments, the layers 104, 120, 150, 204 and/or 208 can have a thickness, or an average thickness, as measured from a respective first side to a respective second side of, of about, of at least or of at most: 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1.0mm, 1.1mm, 1.2mm,

1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2.0mm, 2.1mm, 2.2mm, 2.3mm,

2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3.0mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm,

3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4.0mm, 4.5mm, 5.0mm, 5.5mm, 6.0mm, 6.5mm,

7.0mm, 7.5mm, 8.0mm, 8.5mm, 9.0mm, 9.5mm, 10.0mm, 11.0mm, 12.0mm, 13.0mm, 14.0mm, 15.0mm, 16.0mm, 17.0mm, 18.0mm, 19.0mm, 20.0mm, 21.0mm, 22.0mm, 23.0mm, 24.0mm, 25.0mm, 30.0mm, 35.0mm, 40.0mm, 45.0mm, 50.0mm, 60.0mm, 70.0mm, 80.0mm, 90.0mm or 100.0mm.

In some embodiments, one or more securement elements 222a, 222b can permanently or releasably secure the multilayer filter stack 100 to another object (such as a baffle). In some embodiments, as shown exemplarily in FIG. 1 , the securement elements 222a, 222b can secure the stack 100 to the exhaust hood 58, exhaust hood intake 59 and/or exhaust hood flange 60. In some embodiments, the phrase ‘releasably’ as applied to securement (such as securement elements 222a, 222b) and connection (such as connectors 140, 160, 180, 184, 188, 210) can indicate an easy separation by a user, a separation by a user requiring a low amount of force, a design of the securement element or connector that facilitates easy separation without damaging the elements being connected or secured, and/or the absence of a permanent or lasting securement technology including, but not limited to, weldments, strong adhesives, rivets, brazing, soldering or any other technology known to those skilled in the art.

In various embodiments, the connectors 140, 160, 180, 184, 188 and/or 210 can include magnets, adhesives, mechanical fasteners, biased mechanical fasteners, hook-and-loop panels, tape, double-sided tape, clips, electrostatics, static cling, 3M DUAL LOCK Fasteners, suction devices and/or any other suitable technology for releasable or permanent attachment. The adhesives can include (the same or different) pressure-sensitive adhesives (PSAs). PSAs can include tackified natural rubbers, synthetic rubbers, tackified styrene block copolymers, (meth) acrylics, poly(alpha-olefins) and/or silicones. The adhesives can be oxidatively stable (i.e., maintains adhesion over time) and can exhibit low adhesion build over time. The adhesives can also include (meth)acrylic PSAs being from 80 to 100 weight percent of a C3 — C12 alkyl ester component such as isooctyl acrylate, 2-ethyl-hexyl acrylate and/or n-butyl acrylate, and from 0 to 20 weight percent of a polar component such as acrylic acid, methacrylic acid, ethylene vinyl acetate, N-vinyl pyrrolidone and/or styrene macromer. Such (meth)acrylic PSAs can be used as 100% solids, which can be hot-melt coated or processed via a UV-cured low-viscosity syrup. Optionally, the (meth)acrylic PSA’s can be dispersed in a solvent for coating and/or the (meth)acrylic PSA can be synthesized as a latex polymer dispersion for water-based coating.

In operation, grease generated from the cooking equipment or another source rises, or is suctioned, towards the stack. Airborne droplets of grease can be trapped and/or absorbed by the stack, thus reducing or eliminating or reducing the collection of airborne droplets of grease on a baffle (which can be disposed in an exhaust hood flange). The disclosed technologies can also eliminate or reduce grease traveling downstream through the remainder of the exhaust system. When the stack has accumulated a particular amount, weight or opacity of grease, after a particular time period or after any other metric, it may be desirable to clean or replace a portion of the stack. In such a case, either an upstream-facing layer can be removed (and either discarded or cleaned and placed back on the stack) or the stack can be removed (via the securement elements) and a layer (such as an upstream-facing layer) can be removed and either discarded or cleaned and placed back on the stack. The stack can then be placed again at its filtration position. In some embodiments, the stack can be secured to a baffle, or to any other portion of the exhaust hood or exhaust system.

Thus, versus conventional baffles, the disclosed systems and stack mounting technologies provide a lightweight and cost-effective grease-trapping solution that reduces or prevents the buildup of grease on exhaust system components (such as a baffle, mounting article, duct, blower or exhaust hood), can be installed in or proximate a conventional baffle location in an exhaust hood and facilitates the easy removal and replacement of a releasably secured stack.

The terms and expressions that have been employed are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the embodiments of the present disclosure. Thus, it should be understood that although the present disclosure has been specifically disclosed by specific embodiments and optional features, modification and variation of the concepts herein disclosed may be resorted to by those of ordinary skill in the art, and that such modifications and variations are considered to be within the scope of embodiments of the present disclosure. The complete disclosures of the patents, patent documents, and publications cited herein are incorporated by reference in their entirety as if each were individually incorporated. To the extent that there is any conflict or discrepancy between this specification as written and the disclosure in any document that is incorporated by reference herein, this specification as written will control.

Claims

What is claimed is:

1. A multilayer filter stack, comprising: a first filter layer defining a first side and an opposed second side; a second filter layer defining a first side and an opposed second side, the second filter layer being disposed adjacent the first filter layer; a connector releasably securing the first filter layer to the multilayer filter stack; wherein the first filter layer is adapted to be removable from the multilayer filter stack.

2. The multilayer filter stack of claim 1 , wherein the connector is disposed at a perimeter of the first filter layer and extends outwardly from the perimeter of the first filter layer.

3. The multilayer filter stack of claim 2, further including a third filter layer disposed at an opposite side of the second filter layer than is the first filter layer, and further including a second connector releasably connecting the second filter layer to the multilayer stack, wherein the second filter layer is adapted to be removable from the multilayer filter stack.

4. The multilayer filter stack of claim 3, wherein the second connector is disposed at a perimeter of the second filter layer and extends outwardly from the perimeter of the second filter layer.

5. The multilayer filter stack of claim 4, wherein the connector is releasably connected to the second connector at a location outside of the first perimeter and second perimeter.

6. The multilayer filter stack of claim 1 , wherein the connector is disposed on the second side of the first filter layer and a third connector is disposed on the first side of the second filter layer, the connector on the second side of the first filter layer releasably connecting to the third connector on the first side of the second filter layer.

7. The multilayer filter stack of claim 6, further including a third filter layer disposed on an opposite side of the second filter layer than is the first filter layer, the third filter layer defining a first side and an opposed second side, a fourth connector is disposed on the second side of the second filter layer and a fifth connector is disposed on the first side of the third filter layer that releasably connects to the fourth connector, wherein the second filter layer is adapted to be removable from the multilayer filter stack.

8. The multilayer filter stack of claim 6, wherein the connector releasably connects to the third connector at least partially within a perimeter of the first filter layer.

9. The multilayer filter stack of claim 6, wherein the connector releasably connects to the connector at least partially within a perimeter of the second filter layer.

10. The multilayer filter stack of claim 1, wherein the connector directly connects the second side of the first filter layer to the first side of the second filter layer.

11. The multilayer filter stack of claim 10, further including a third filter layer disposed on an opposite side of the second filter layer than is the first filter layer, and further including a sixth connector releasably connecting the second side of the second filter layer to the first side of the third filter layer.

12. The multilayer filter stack of claim 1 , wherein the first filter layer is upstream of the second filter layer when both filter layers are disposed in a fluid flow.

13. The multilayer filter stack of claim 12, wherein a third filter layer is disposed downstream of the first filter layer and the second filter layer when all three filter layers are disposed in the fluid flow.

14. The multilayer filter stack of claim 1 , wherein the connector includes adhesive tape.

15. The multilayer filter stack of claim 1, wherein the connector includes an adhesive.

16. The multilayer filter stack of claim 1 , wherein the connector includes hook and loop panels.

17. The multilayer filter stack of claim 1, wherein the connector includes a mechanical restraint.

18. The multilayer filter stack of claim 1, wherein at least one of the first filter layer and the second filter layer includes a flame-resistant material.

19. A method for forming a multilayer filter stack, the method comprising: providing a multilayer filter roll, the multilayer filter roll including a first filter layer, a second filter layer, and a connector releasably securing the first filter layer to the second filter layer; unrolling at least a portion of the multilayer filter roll; and separating the portion of the multilayer filter roll from the remainder of the multilayer filter roll to form the multilayer filter stack.

20. The method of claim 19, wherein a liner is disposed between at least some multilayer rolled layers of the multilayer filter roll.