Filter-coalescing element

Abstract

In one aspect, the invention provides an element for use in a filter device that includes a riser tube, the element comprising a first segment comprising a first lumen capable of particulate filtration, a second segment comprising a second lumen capable of coalescing separation, and a third non-porous segment comprising a third lumen positioned between the first segment and the second segment, wherein the first lumen, the second lumen, and the third lumen being contiguous with one another. In further aspects, the invention also provides additional elements, as well as methods for manufacturing and assembling the disclosed elements.

Description

[0001] FILTER-COALESCING ELEMENT

[0002] CROSS REFERENCE TO RELATED APPLICATIONS

[0003] This application claims priority benefit from U.S. Provisional Application No. 63 / 675,663 filed July 25, 2024, which is incorporated by reference herein in its entirety.

[0004] FIELD OF THE INVENTION

[0005] The present invention relates to field of filtration and. more particularly, to devices and the parts therein used to filter liquid and gas streams.

[0006] BACKGROUND OF THE INVENTION

[0007] Filtration is a physical process that separates solid matter and fluid (e.g., a liquid or a gas fluid) from in a mixture comprising the solid matter and the fluid. Filtration devices are well known. The filter element is the component in a filtration device where the actual filtration occurs. Particulate filter elements and coalescing separator elements are well known and have been utilized to remove solid particles and liquid aerosols from compressed gas streams for many years. Particulate Filtration is the removal of solid particles from a gas or liquid. The liquid or gas flows through the element from the outside to inside. The unclean liquid or gas flows into the filter, and then the clean liquid or gas emerges. The size of the particle removed depends upon the grade of the filter element (e.g., from 0.01 microns to 200 microns or higher). Some particulate filters are honeycomb shaped and traps the unwanted particles while releasing the cleaned liquid or gas product. Coalescing Separator Filtration is the separation of two phases of matter (e.g., liquid and gas) from each other and into separate units. Some mixed phases, including water and gas mixtures, and gas and oil mixtures, need to be separated either for purification or for commercialization. Typically, a coalescing filter includes an inner capture layer that is a high efficiency coalescing layer and the outer is a coarser drainage layer. Using a mixture of water and gas as an example, the water and gas mixture enters the inside of the filter, which includes a high efficiency coalescing layer, and the liquid water droplets run along fine fibers of the inner layer of the coalescing filter to fomi (or coalesce) into larger drops. These larger drops of water are then drained away using gravity or other force to pull the drops from the gas, and the gas leave through tire outer drainage layer of the filter, releasing dry gas as the final product.

[0008] It would be useful to have improved elements for use in removing solid particles and liquid aerosols from streams of fluid, such as gas or liquid streams. SUMMARY OF THE INVENTION

[0009] In some embodiments, the invention is based on the surprising development of a two-stage filtercoalescing element that avoids contamination of liquid droplets in the resulting gas product.

[0010] In a first aspect, the invention provides an element for use in a filter device that includes a riser tube, the element comprising a first segment comprising a first lumen capable of particulate filtration, a second segment comprising a second lumen capable of coalescing separation, and a third non-porous segment comprising a third lumen positioned between the first segment and the second segment, wherein the first lumen, the second lumen, and tire third lumen being contiguous with one another.

[0011] In some embodiments, tire first segment and the second segment are substantially similar in length. In some embodiments, when the element is positioned in the riser tube, a portion of the third segment element extends downstream from the riser tube in the filtration device. In some embodiments, the second segment tapers as it extends downstream. In some embodiments, the second segment further comprises a drain hole and / or a drain pan.

[0012] In another aspect, the invention provides a tubular filter element for use in a filtration device comprising a riser tube, the element comprising a first segment comprising a first lumen capable of particulate filtration and a second segment comprising a second lumen capable of coalescing separation, the first lumen and tire second lumen being contiguous with one another, wherein when the element is positioned in the riser tube, a majority of a portion of the element covered by the riser tube is from the first segment.

[0013] In some embodiments, when the element is positioned in the riser tube, the portion of the element covered by the riser tube is substantially all from the first segment. In some embodiments, the element is positioned in the riser tube, a portion of the first segment extends downstream from the riser tube in the filtration device. In some embodiments, the second segment tapers as it extends downstream. In some embodiments, the second segment further comprises a drain hole and / or a drain pan.

[0014] In yet another aspect, the invention provides a method of manufacturing and assembling a tubular filter element comprising manufacturing a first segment capable of particulate filtration, said segment comprising a first lumen; manufacturing a second segment capable of coalescing separation, said second segment comprising a second lumen; manufacturing a third segment connected to either the first segment or second segment, said third segment comprising a lumen and tube walls comprising non-porous material; and assembling the element by connecting the first segment or the second segment to the third segment when the filter element is inserted into a riser tube in a filtration device, wherein, the first lumen, second lumen, and third lumen are contiguous with one another.

[0015] In some embodiments, the second segment tapers as it extends downstream. In some embodiments, the second segment further comprises a drain hole and / or a drain pan.

[0016] In some embodiments, a drain pan and / or drain hole can be added to the bottom of the coalescing stage to allow liquids that drain from that stage to drain to a region of low gas flow and not drip onto other elements.

[0017] In another embodiment of the present invention, the coalescing separator stage can be tapered and a drain pan can be added to the bottom of the coalescing stage to allow liquids the drain from that stage to drain to a region of low gas flow and not drip onto other elements.

[0018] In another aspect, the invention provides a tubular filter element for use in a filtration device comprising a riser tube, the element comprising a first segment comprising a first lumen configured for particulate filtration, a second segment comprising a second lumen configured for coalescing separation, and a third non-porous segment comprising a third lumen positioned between the first segment and the second segment, wherein the first lumen, the second lumen, and the third lumen being contiguous with one another.

[0019] In some embodiments, the first segment and the second segment are substantially similar in length. In some embodiments, when the element is positioned in the riser tube, a portion of the third segment element extends beyond a downstream end of the riser tube in the filtration device. In some embodiments, the second segment tapers as it extends downstream. In some embodiments, the second segment tapers at its end. In some embodiments, the element further comprises a drain hole and / or a drain pan at the bottom of the second segment.

[0020] In another aspect, the invention provides a tubular filter element for use in a filtration device comprising a riser tube, the element comprising a first segment comprising a first lumen configured for particulate filtration and a second segment comprising a second lumen configured for coalescing separation, the first lumen and the second lumen being contiguous with one another, wherein when the element is positioned in the riser tube, a majority of a portion of the element covered by the riser tube is from the first segment.

[0021] In some embodiments, when the element is positioned in the riser tube, the portion of the element covered by the riser tube is substantially all from the first segment. In some embodiments, when the element is positioned in the riser tube, a portion of the first segment extends beyond a downstream end of the riser tube in the filtration device. In some embodiments, the second segment tapers as it extends downstream. In some embodiments, the second segment tapers at its end. In some embodiments, a drain hole and / or a drain pan is added to the bottom of the second segment.

[0022] In yet another aspect, the invention provides a method of manufacturing and assembling a tubular filter element comprising manufacturing a first segment configured for particulate filtration, said segment comprising a first lumen; manufacturing a second segment configured for coalescing separation, said second segment comprising a second lumen; manufacturing a third segment connected to either the first segment or second segment, said third segment comprising a lumen and tube walls comprising non- porous material; and connecting the first segment or the second segment to the third segment when the filter element is inserted into a riser tube in a filtration device, wherein, the first lumen, second lumen, and third lumen are contiguous with one another.

[0023] In some embodiments, tire second segment tapers as it extends downstream. In some embodiments, the second segment tapers at its end. In some embodiments, a drain hole and / or a drain pan is added to the bottom of the second segment.

[0024] In some embodiments, tire path of coalesced liquids from the first stage is drained from the element in a region of low velocity gas flow.

[0025] BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Tire patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the Office upon request and payment of the necessary fee.

[0027] FIG 1 is a diagrammatic cross-sectional view of a prior art multi -chambered filter / separator vessel (1) as described in US Patent 5,919,284 issued to Perry Jr. et al. Hie area to the left of the tube sheet (7) is tire particulate filter element chamber (2) and the area to the right is the coalescing separator chamber (3).

[0028] FIG 2 is a diagrammatic view of a prior art filter separator element (or filter coalescing element) (9) comprising a combined particulate filter stage (10) and coalescing separator element (11).

[0029] FIG 3 is a diagrammatic cross-sectional view of prior art filter separator element (combined particulate filter element and coalescing separator element) of FIG 2 installed into the filter separator vessel of FIG 1.

[0030] FIG 4 is a cross-sectional view of FIG 2 showing flow path of gas and liquids. FIG 5 is a diagrammatic view of an embodiment of the invention wherein the combination particulate fdter element and coalescing separator element has non-porous center segment.

[0031] FIG 6 is a cross-sectional view of FIG 5 showing flow path of gas and liquids.

[0032] FIG 7 is a diagrammatic view of FIG 5 where the coalescing separator stage is tapered.

[0033] FIG 8 is a diagrammatic view of FIG 8 with both a drain hole and a drain pan.

[0034] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0035] The invention stems, in part, from the development of a two-stage filter-coalescing element, and methods for making the same.

[0036] The published patents, patent applications, websites, company names, and scientific literature referred to herein establish the knowledge that is available to those with skill in the art and are hereby incorporated by reference in their entirety to tire same extent as if each was specifically and individually indicated to be incorporated by reference. Any conflict between any reference cited herein and the specific teachings of this specification shall be resolved in favor of the latter.

[0037] Temis defined or used in the description and the claims shall have the meanings indicated, unless context otherwise requires. Technical and scientific terms used herein have the meaning commonly understood by one of skill in the art to which the present invention pertains, unless otherwise defined. Any conflict between an art-understood definition of a word or phrase and a definition of the word or phrase as specifically taught in this specification shall be resolved in favor of the latter. As used herein, the following temis have the meanings indicated. As used in this specification, the singular fomis “a,” "an" and "the" specifically also encompass the plural forms of the temis to which they refer, unless the content clearly dictates otherwise. The term “about” is used herein to mean approximately, in the region of, roughly, or around. When the term “about” is used in conjunction with a numerical range, it modifies that range by extending the boundaries above and below the numerical values set forth. In general, the term “about” is used herein to modify a numerical value above and below the stated value by a variance of 20%.

[0038] Particulate filter elements and coalescing separator elements are well known and used in filtration devices in many industries ranging from the phamiaceutical industry’ to the oil industry. Recently, particulate filter elements and have been combined into a single replaceable two stage element instead of two separate elements. U.S. Patent 5,919.284 issued to Perry. Jr. et al. describes the use of a multichambered vessel using a particulate filter element and coalescing separator element that are combined into a single replaceable element called a filter separator element. A cross-sectional view drawing of the vessel (also referred to herein as a filter device or filter separator vessel) described in US Patent 5,919,284 is shown in FIG 1. The filter separation vessel (1) includes a particulate filter chamber (2), a coalescing separator chamber (3), an inlet (4), an outlet (5), multiple riser tubes (each, 6), a tube sheet (7), and a vessel closure (8). A filter-coalescing element (also referred to as a filter separating element) is shown in Figure 2. The filter end of the filter separator element is referred to as being upstream, and this portion of the filter separator element is referred to as the particulate filter stage (10) while the coalescing end of the filter separator element is referred to as being downstream, and this portion of the filter separator element is referred to as the coalescing separator stage (11). The multiple filter-coalescing elements are inserted into the filter device by removing the cap at the vessel closure (8) and inserting each filter element into one of the multiple riser tubes (6). FIG 2 shows a filter separator element (9) that is insertable (see FIG 3) into one of the riser tubes in the device of FIG 1.

[0039] Tire benefit of this single element is that the element can be quickly changed through a single opening in the multi -chambered vessel, significantly reducing maintenance costs. However, the combination of the particulate filter element and coalescing separator element can cause coalescing of liquids to occur when gas flows through the particulate filter element stage. This is because the velocity of the gas is extremely high at the downstream end of the riser tube. FIG 4 shows the flow of gas through the filter separator element of FIG 2 when it is inserted into a riser tube in the device of FIG 1. As shown in Fig. 4, flowing gas with liquid droplets (12) enters the particulate filter stage (10) of the filter separator element, and flowing gas without liquid droplets (13) exits the coalescing separator stage of the filter separator element. As shown in Fig. 4, however, flowing liquid (14) collects in the particulate filter stage (10) of the filter separator element upstream of the riser tube (6) and tube sheet (7). Indeed, as shown in Fig. 4, flowing liquid (14) spills out of tire riser tube of the prior art filter separator element into the coalescing separator chamber of the filter device. Computation fluid dynamics (CFD) flow rate was determined as gas exits the riser tube and through the coalescing separator stage of the prior art filter separator element. The flow at the downstream end of the riser tube (e.g.. adjacent to the tube sheet) was found to be higher than the annular velocity at the downstream end of the coalescing end of the prior art filter separator element. The coalesced liquids drop to the bottom, inside surface of the particulate filter element stage of the prior art filter separator element and flow toward the coalescing separator element stage of the prior art filter separator element. Once the coalesced liquids reach the coalescing filter element stage (item 11 in Fig. 2), tire liquid starts to drain through the coalescing filter element stage, from inside the lumen of the filter separator element to the outside of the element where it collects in the tubular shaped riser tubes (item 6 in Fig. 1) of the filter separator vessel. The liquid then flows through the riser tubes guides until reaching the coalescing chamber where the liquid drains down to the bottom of the coalescing chamber (item 3 in Fig. 1). The flow of gas also passes through the riser tubes. The velocity of the gas increases as it flows through the riser tubes (item 6 in Fig. 1) until it reaches the coalescing chamber (item 3 in Fig. 1). The combination of liquids and increasing velocity of gas can cause the liquid to break up into small droplets and become re-entrained into the flow of gas. When liquid droplets become re-entrained in tire flow of gas downstream of the filter separating element then those liquid droplets can be carried out of the vessel and contaminate downstream processes.

[0040] In some embodiments of the present invention, a single element comprising both a particular filter portion and a coalescing filter portion has been surprisingly developed, as described herein, which overcomes tire problem of coalescing liquid re-entraining (i.e., re-entering) the flow of gas by providing means for liquids that are coalesced in the filter element stage of filter separator element to drain in a region with little to no flow of gas. A non-limiting example of an element of the invention as described herein is shown in FIG 5. As can be seen in Fig. 5, a non-limiting element (item 15) of the invention as described herein comprises a filter portion at the particulate filter stage (16) and a coalescing portion at the coalescing separator stage (18), separated by a center segment (17) that is non-porous. Of course, the non-limiting element as described herein as a whole remains a tube with a lumen contiguous through the entire element, but tire sides of the tube comprising the center segment are non-porous. Such a configuration allows for substantially less re-entrainment of liquids into the flow gas thereby improving the overall liquid removal efficiency. In the element described herein, the liquids and gases are routed in manner so as to not flow through tire riser tubes. In the invention described herein, in some embodiments, the coalesced liquids from the particulate filter element are allowed to drain separately from high velocity gases, thereby preventing the coalesced liquid from re-entraining (i.e.. re-entering) into the flow of gas. As a result of using the single element described herein, a dry, clean gas product was achieved.

[0041] In some embodiments, the present invention solves the problem in the prior art by providing a three-part tubular element that includes a particle filter portion, a coalescing separator portion, and a third portion comprising a tube of non-porous material that connects the particle filter portion and the coalescing separator portion.

[0042] In another embodiment, the invention provides a two-part tubular element, where the portion of the tube covered by the riser tube is mostly the filter segment (e g., where the gas enters the lumen from the outside of the tube) and only a small portion, or none, of the coalescing segment (e.g., where the gas leaves the lumen and exits to the outside of the tube) is covered by tire riser tube.

[0043] In yet another embodiment of the present invention, the invention provides a non-porous tube that connects the particle filter portion to the coalescing separator portion of the element in manner that does not allow gas to flow through the riser tube. In other words, unlike the unlike the particle filter portion, which allows gas to flow through the sides of the tube into the lumen of the tube, and unlike the coalescing separator portion, which allows gas to flow from the lumen of the tube to the outside of the tube, the third portion, comprising non-porous sides, does not allow gas to enter or exit the lumen of the tube. Tire flow of gas {and any accompanying liquid) through a non-limiting element of the invention is shown in FIG 6. In this manner, the gas (and any accompanying liquid) within the lumen of the tubular three-portion element does not exit the lumen and does not directly contact the inside surface of the riser tubes.

[0044] The gas particle filter separator portion and the coalescing separator portion of tire filter element described herein may be constructed in the manner and of the materials well known in the art (see e.g., US Patent Nos. 4,101,423; US 4,986,909, US 5,114,582; US 5,264,162 and US 5,827,430, the entire disclosures of each of which is incorporated by reference herein. A suitable filter element for use in the present invention is the Peach™ filter commercially available from Perry Equipment Corporation of Mineral Wells, Tex. For example, in some embodiments, the gas filter separator / coalescer element may comprise four multi -overlapped layers of nonwoven fabric strip of varying composition. The first layer may be composed of equal amounts by volume of fibers purchased from Hoechst Celanese of Charlotte, N.C., United States, sold under the fiber designation "252, ""271, "and "224," has a basis weight of 0.576 ounces per square foot, is ten inches wide, and is overlapped upon itself five times. The denier of fiber "252" is 3 and its length is 1.500 inches. The denier of fiber "271" is 15 and its length is 3.000 inches. The denier of fiber "224" is 6 and its length is 2.000 inches. The second layer may be composed of equal amounts by volume of "252,""271," and "224." has a basis weight of 0.576 ounces per square foot, is eight inches wide, and is overlapped upon itself four times. The third layer may be composed of equal amounts by volume of "252," "271," and "224," has a basis weight of 0.576 ounces per square foot, is eight inches wide, and is overlapped upon itself four times. The fourth layer may be composed of equal amounts by volume of "252" and a fiber sold under the name "Tairilin," has a basis weight of 0.576 ounces per square foot, is six inches wide, and is overlapped upon itself three times. Fiber "252" being of the core and shell type serves as the binder fiber in each of tire aforementioned blends.

[0045] In some embodiments, tire filter coalescing element described herein can coalesce and remove 99% of all liquid droplets 0.3 microns and larger and can remove 99% of all solid particles 0.3 microns and larger at a combined pressure drop of approximately one to three pounds per square inch gauge. In some embodiments, the filter coalescing element described herein can coalesce and remove 99.5% of all liquid droplets 0.3 microns and larger and can remove 99.5% of all solid particles 0.3 microns and larger at a combined pressure drop of approximately one to three pounds per square inch gauge. In some embodiments, the filter coalescing element described herein can coalesce and remove 99.8% of all liquid droplets 0.3 microns and larger and can remove 99.99% of all solid particles 0.3 microns and larger at a combined pressure drop of approximately one to three pounds per square inch gauge.

[0046] In other embodiments of the present invention, a non-limiting combined element can be manufactured in two or more segments and installed together in the field such as, for example, at the site of a filter device into which the element will be inserted (see, e.g., Fig. 3).

[0047] In yet another embodiment of the present invention, the coalescing stage end of the element can be tapered. Such a tapered coalescing end of the element is depicted in FIG 7. In some embodiments, a drain hole and / or a drain pan can be added to the bottom of tire coalescing stage end of the element to allow liquids from the coalescing stage of one element to drain to a region of low gas flow and not drip onto other elements, including, for example, other elements in filter devices that hold multiple elements. FIG 8 depicts the coalescing stage end of an element, with both the drain hold and the drain pan. It should be noted that although FIG 8 depicts both the drain hole and the drain pan on a coalescing stage end (18) that is tapered, the element (15) depicted in FIG 8 is merely exemplary, and it will be understood that the coalescing stage end of an element as described herein need not be tapered to comprise a drain hole and / or a drain pan.

[0048] In other embodiment of the present invention, the element described herein can be manufactured in two or more segments and installed together in the field.

[0049] The embodiments of the invention described above are intended to be merely exemplary; numerous variations and modifications will be apparent to those skilled in the art. All such variations and modifications are intended to be within the scope of the present invention as defined in any appended claims.

Claims

Claims1. A tubular filter element for use in a filtration device comprising a riser tube, the element comprising a first segment comprising a first lumen configured for particulate filtration, a second segment comprising a second lumen configured for coalescing separation, and a third non-porous segment comprising a third lumen positioned between the first segment and tire second segment, wherein the first lumen, the second lumen, and the third lumen being contiguous with one another.

2. The element of claim 1, wherein the first segment and the second segment are substantially similar in length.

3. The element of claim 1, wherein when the element is positioned in the riser tube, a portion of the third segment element extends beyond a downstream end of the riser tube in the filtration device.

4. The element of claim 1, wherein the second segment tapers at its end.

5. The element of claim 4, further comprising a drain hole and / or a drain pan at a bottom of the second segment.

6. A tubular filter element for use in a filtration device comprising a riser tube, the element comprising a first segment comprising a first lumen configured for particulate filtration and a second segment comprising a second lumen configured for coalescing separation, the first lumen and the second lumen being contiguous with one another, wherein when the element is positioned in the riser tube, a majority of a portion of the element covered by the riser tube is from the first segment.

7. The element of claim 6, wherein when the element is positioned in the riser tube, the portion of the element covered by the riser tube is substantially all from the first segment.

8. The element of claim 6, wherein when the element is positioned in the riser tube, a portion of the first segment extends beyond a downstream end of he riser tube in the filtration device.

9. The element of claim 6, wherein the second segment tapers at its end.

10. Tire element of claim 9, wherein a drain hole and / or a drain pan is added to the bottom of the second segment.

11. A method of manufacturing and assembling a tubular filter element comprising a) manufacturing a first segment configured for particulate filtration, said segment comprising a first lumen; b) manufacturing a second segment configured for coalescing separation, said second segment comprising a second lumen; c) manufacturing a third segment connected to either tire first segment or second segment, said third segment comprising a lumen and tube walls comprising non-porous material; and d) connecting the first segment or the second segment to tire third segment when the filter element is inserted into a riser tube in a filtration device, wherein, the first lumen, second lumen, and third lumen are contiguous with one another.

12. The method of claim 11, wherein the second segment tapers at its end.

13. Tire method of claim 11, wherein a drain hole and / or a drain pan is added to the bottom of the second segment.

Images