Abstract:
A device for filtering a gas stream, having a vessel partitioned into a first stage and a second stage, with an opening between stages. A filter element is positioned in the opening, with ends of the filter element extending into the first and second stages. The first member is removable from the second member while the filter element is positioned in the opening, to allow for replacement with a new clean member.

Description:
RELATED APPLICATION DATA 
     This application is a Continuation-In-Part (CIP) of and claims priority of U.S. patent application Ser. No. 12/396,570, filed Mar. 3, 2009, which application is incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to methods, apparatus and products for filtering. In another aspect, the present invention relates to methods, apparatus and products for filtering streams of gas and/or liquids to remove solids and/or entrained liquids. In even another aspect, the present invention relates to methods, apparatus and products for filtering, utilizing a filter system in which that portion of the filter system more likely to accumulate filtrate is replaceable apart from that portion of the filter system which is less likely to accumulate filtrate. In even another aspect, the present invention relates to methods, apparatus and products for filtering, utilizing a two stage filter system in which that portion of the filter system in the first stage is more likely to accumulate filtrate is replaceable apart from that portion of the filter system in the second stage which is less likely to accumulate filtrate. In still another aspect, the present invention relates to a sealing arrangement for sealing the filter system in the sealing vessel. 
     2. Brief Description of the Related Art 
     There are a number of applications in which it is necessary to remove solids or liquids from a gas stream, liquid stream, or multi-phase stream. As a non-limiting example, solid or liquid contaminants may be present in various gas or liquid streams of a refrigeration system. As another non-limiting example, gas pipelines many times contain solid or liquid contaminants. 
     Various apparatus and methods for removing solids and/or liquids from gas streams are well known. Quite commonly, gas filter elements are utilized for filtering dry gas streams as well as for separating solids and liquids from contaminated gas streams, or for coalescing entrained liquids from a gas stream. Often these types of gas filter elements are installed in multi-stage vessels, which are in turn installed in a gas pipeline, to perform these filtering functions. 
     There are a number of patents that relate to removing solids and/or liquids from gas streams, the follow of which are merely a small sampling. 
     U.S. Pat. No. 6,381,983, issued May 7, 2002, to Angelo et al., discloses an improved filter drier for a refrigeration system having a replaceable tubular filter element. A desiccant assembly is removably secured within a housing. The assembly includes a first and second molded desiccant, a hollow tubular perforated core located within said first and second molded desiccant, and a tubular filter located over said core. 
     U.S. Pat. No. 6,692,639, issued Feb. 17, 2004, to Spearman et al., discloses a conically shaped filtration and/or separation apparatus that is constructed from a stack of filters at least some of which are different sizes superposed above each, other, of said plurality of said filters in a fluid communicable relationship. A collapsible version of such conically shaped filter and/or separation apparatus is provided whereby a plurality of such filters are connected together using two piece interlocking or connecting end caps. 
     U.S. Pat. No. 6,858,067, issued Feb. 22, 2005, to Burns et al., discloses a filtration vessel for use with a rotary screw compressor that receives a compressed liquid/gas mixture from the compressor. The vessel utilizes a first stage vortex knockout region to remove bulk liquids through a circular motion that imposes centrifugal forces on the gas and liquid mixture. A coalescer region located above the vortex knockout region receives the relatively lighter fluids and separates any remaining entrained liquids from the fluids. The discharge from the filtration unit is an essentially liquid free compressed gas. The liquid discharge, in the case of lube oil can be recirculated to the compressor for another cycle. 
     U.S. Pat. No. 7,051,540, issued May 30, 2006, to TeGrotenhuis et al., discloses a wick-containing apparatus capable of separating fluids and methods of separating fluids. 
     U.S. Patent Application Publication No. 20070095746, published May 3, 2007 to Minichello et al., discloses an apparatus for filtering a gas or liquid stream such as a natural gas stream. The apparatus includes a closed vessel having a longitudinally extending length, an initially open interior, an inlet port at one extent and an outlet port at an opposite extent thereof. A partition located within the vessel interior divides the vessel interior into a first chamber and a second chamber. At least one opening is provided in the partition. A filter element is disposed within the vessel to extend from within the first chamber. A special seal structure formed of a resilient material and having conically shaped sidewalls is used to seal against one end of the filter element as well as forming a dynamic seal with the vessel riser in use. 
     U.S. Pat. No. 7,270,690, issued Sep. 18, 2007, to Sindel, discloses a separator vane assembly made up of a number of corrugated vanes that provide serpentine paths for the gas stream therethrough. As the gas stream flows through the serpentine paths, it changes direction and liquid in the gas stream impacts the surfaces of the vanes. The upstream section of the vane assembly has roughened surfaces to decrease the surface tension of the liquid, thereby causing the liquid to coalesce. The downstream section of the vane assembly has smooth surfaces so as to increase the surface tension of the liquid. The vane assembly is followed by filters, which capture the liquid that passes through the vane assembly. The vane assembly coalesces the liquid to enable the filters to operate more effectively. 
     U.S. Patent Application Publication No. 20070251876, published Nov. 1, 2007 to Krogue et al., discloses an apparatus for filtering a gas or liquid stream of impurities and to filter elements used in such an apparatus. The apparatus includes a closed vessel having a longitudinally extending length, an initially open interior, an input port at one extent and an output port at an opposite extent thereof. A partition located within the vessel interior divides the vessel interior into a first stage and a second stage. At least one opening is provided in the partition. A filter element is disposed within the vessel to extend from within the first stage. The filter element is made up of a carbon block filter media surrounded by a protective porous depth filter media. 
     U.S. Pat. No. 7,314,508, issued Jan. 1, 2008, to Evans, discloses a desiccant cartridge having a seal therearound for forming a proper seal between the cartridge and the canister of a receiver/dryer or accumulator assembly includes a cup extending along an axis having inner wall portion and outer wall portion connected to a transverse portion to define a chamber containing desiccant particles. A cap is secured to cup to secure the desiccant particles inside the chamber. The outer wall portion is provided with the seal that is composed of a flexible thermoplastic elastomer that is resistant to heat during welding shut of the canister. 
     U.S. Pat. No. 7,332,010, issued Feb. 19, 2008, to Steiner, discloses a two or three phase separator including a centrifugal separator, a demister (if a three phase separator), and a filter contained within a housing. The filter uses an outside-in flow principle. The filter includes an inner layer or a center core that defines a hollow interior. An outer layer is positioned adjacent and surrounding the inner layer. The outer layer includes a re-enforcement layer, a first particle filter layer, a coalescer layer, and a second particle filter layer. An access cover of the separator includes a cover plug, an actuator cam, a plurality of idler cam plates, and a plurality of mechanisms. The access cover cooperates with an opening and an annular groove in the housing to close off and seal the separator. 
     U.S. Pat. No. 7,344,576, issued Mar. 18, 2008, to TeGrotenhuis et al., discloses methods of separating fluids using capillary forces and/or improved conditions. The improved methods may include control of the ratio of gas and liquid Reynolds numbers relative to the Suratman number. Also disclosed are wick-containing, laminated devices that are capable of separating fluids. 
     Quite commonly in pipeline applications, it is not uncommon to see multi-stage vessels, as well as a multitude of other similar filtration vessels, that utilize solid or hollow core tubular elements, typically formed at least partially a porous filtration media. Non-limiting examples of such vessels include filtration equipment such as shown in U.S. Pat. No. 5,919,284, issued Jul. 6, 1999 or U.S. Pat. No. 6,168,647, issued Jan. 2, 2001, both to Perry, Jr. et al. 
     U.S. Pat. No. 5,919,284 discloses a gas filter separator coalescer and multi-stage vessel for separating liquids and solids from a gas stream and simultaneously coalescing liquids from the gas stream. The apparatus includes a closed vessel having a longitudinally extending length, an initially open interior, an input port at an extent and an output port at an opposite extent thereof. There is a partition located within the vessel interior that divides the vessel interior into a first stage and a second stage. There is at least one opening in the partition. A separator/coalescer filter element is disposed within the vessel to sealingly extend from within the first stage through the opening into the second stage. There is a chevron-type seal or an O-ring seal between the filter element and the opening. The input port, vessel interior, separator/coalescer filter element and output port together define a flow passage within the apparatus, whereby the gas stream flows into the first stage through the input port and through the filter element hollow core, thereby filtering solids out of the gas stream, separating liquids from the gas stream, and pre-coalescing liquids in the gas stream. The gas stream then flows along the hollow core past the partition and back through the filter element into the second stage, thereby coalescing liquids out of the gas stream, the gas stream then exiting the second stage through the outlet port. 
     U.S. Pat. No. 6,168,647 discloses an apparatus for separating liquids and solids from a gas stream and simultaneously coalescing liquids from the gas stream. The apparatus includes a closed vessel having a longitudinally extending length, an initially open interior, an input port at an extent and an output port at an opposite extent thereof. There is a partition located within the vessel interior that divides the vessel interior into a first stage and a second stage. There is at least one opening in the partition. A separator/coalescer filter element is disposed within the vessel to sealingly extend from within the first stage through the opening into the second stage. There is a chevron-type seal or an O-ring seal between the filter element and the opening. The input port, vessel interior, separator/coalescer filter element and output port together define a flow passage within the apparatus, whereby the gas stream flows into the first stage through the input port and through the filter element hollow core, thereby filtering solids out of the gas stream, separating liquids from the gas stream, and pre-coalescing liquids in the gas stream. The gas stream then flows along the hollow core past the partition and back through the filter element into the second stage through a louvered impingement baffle, thereby coalescing liquids out of the gas stream, the gas stream then exiting the second stage through the outlet port. The louvered impingement baffle conditions the gas stream to create a scrubbing effect on any fine mist exiting the separator/coalescer filter element. 
     With such equipment as disclosed in the U.S. Pat. No. 5,919,284 or 6,168,647, it is periodically necessary to perform maintenance on the filtration vessels, including replacement of the porous filter elements. This task is labor intensive and time consuming in situ because of the mounting structure used to mount the filter elements within the filtration vessel interior. Often, it is necessary to unscrew the end cap or nut to free the filter element from its associated structural mounting within the vessel interior. Not only is this time consuming, but the location of the mounting structure is sometimes inconvenient to access, making filter replacement a difficult or inconvenient chore. The same type of inconveniences is present in the initial filter installation process for new filtration vessels. 
     Specifically for filter systems of the type disclosed in U.S. Pat. No. 6,168,647, there are at least two reasons for the difficulty in removing the filter elements. First, the chevron seal is working against the removal direction when trying to remove the element. Second, since the filter element extends into the riser assembly, solids collect and pack into the riser assembly. Additionally, it is not uncommon to find damage to the downstream expanded metal support grid generally caused by the elements being shoved in too far. 
     In an effort to overcome the problems of the prior art, especially the deficiencies of U.S. Pat. No. 5,919,284 or 6,168,647, further development was advanced in U.S. Pat. No. 7,014,685, issued Mar. 21, 2006, and U.S. Pat. No. 7,108,738, issued Sep. 19, 2006, both to Burns et al. These two patents disclose an apparatus for filtering a gas or liquid stream such as a natural gas stream. The apparatus includes a closed vessel having a longitudinally extending length, an initially open interior, an input port at one extent and an output port at an opposite extent thereof. A partition located within the vessel interior divides the vessel interior into a first stage and a second stage. At least one opening is provided in the partition. A filter element is disposed within the vessel to extend from within the first stage. The filter element is easily mounted or removed from the vessel by rotating a J-slot engagement surface on the element which mates with a post provided on a mounting structure provided on the vessel partition. 
     However, in spite of the above advancements that have been made in overall filtration vessel design, there still exists a need in art for apparatus and methods for filtration. 
     There also exists a need in the art for apparatus and methods for improvements that simplify the process of mounting and replacing filter elements within the filtration vessel, thereby decreasing the cost of vessel installation and maintenance. 
     As a non-limiting example of a desired improvement, for filtration systems as disclosed in U.S. Pat. Nos. 5,919,284, and 6,187,647, the portion of the filter element positioned in the downstream stage is generally a lot cleaner than the portion of the filter element positioned in the upstream stage. However, with these filtration systems, the entire filter element is removed and replaced, even though the downstream portion of the filter may be readily further used. 
     These and other needs in the art will become apparent to those of skill in the art upon review of this specification, including its drawings and claims. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide for apparatus and methods for filtration. 
     It is another object of the present invention to provide for apparatus and methods for improvements that simplify the process of mounting and replacing filter elements within the filtration vessel, thereby decreasing the cost of vessel installation and maintenance. 
     It is even another object of the present invention to allow the use of different removal efficiencies of filter elements in the first and second stages based on the application and/or operator&#39;s requirements. 
     These and other objects of the present invention will become apparent to those of skill in the art upon review of this specification, including its drawings and claims. 
     According to one embodiment of the present invention there is provided an apparatus for filtering a gas. The apparatus may include a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages. The apparatus also may include a filter element positioned in the opening comprising first member having a first connection end and a second member having a second connection end. This the first and second members may be connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, wherein at least a portion of the first member extends into the first stage, and at least a portion of the second member extends into the second stage, and wherein the first member is removable from the second member while the filter element is positioned in the opening. 
     According to another embodiment of the present invention, there is provided a method of operating a filtering apparatus. The filtering apparatus may comprise a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages, and further comprises a filter element positioned in the opening comprising a first member having a first connection end and a second member having a second connection end, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, wherein at least a portion of the first member extends into the first stage, and at least a portion of the second member extends into the second stage. The method may include separating the first member from the second member, while the filter element is positioned in the opening, thereby leaving at least a portion of the second member extending into the second stage. 
     According to even another embodiment of the present invention, there is provided a method of operating a filtering apparatus. The filtering apparatus may comprise a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages, and further comprises a filter element positioned in the opening comprising a first member having a first end and a second member having a second connection end, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end engage to provide the connection, wherein at least a portion of the first member extends into the first stage, and at least a portion of the second member extends into the second stage. The method may include replacing the first member with a replacement member. 
     According to still another embodiment of the present invention, there is provided an apparatus for filtering a gas. The apparatus may include a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages. The apparatus may also include a riser extending from the opening, said riser having a first end with a straight portion and a second end with a flared portion, with the straight portion positioned nearer the opening than the flared portion. The apparatus may also include a filter element having at least a portion positioned in the riser the filter element comprising a first member having a first connection end and a first filtering characteristic, and a second member having a second connection end and a second filtering characteristic, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, with the second connection end defining a first groove extending circumferentially around the second connection end with a first seal member residing in the first groove, wherein at least a portion of the second connection end is positioned in the riser with the first seal member engaging the straight portion of the riser, wherein at least a portion of the first member extends toward the first stage, and at least a portion of the second member extends toward the second stage, wherein the first member is removable from the second member while the filter element is positioned in the opening, and wherein the first filtering characteristic and the second filtering characteristic are the same or different. 
     According to yet another embodiment of the present invention, there is provided a method of operating a filtering apparatus, wherein the filtering apparatus comprises a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages, a riser extending from the opening, said riser having a first end with a straight portion and a second end with a flared portion, with the straight portion positioned nearer the opening than the flared portion, and further comprises a filter element positioned in the riser comprising a first member having a first connection end and a first filtering characteristic and a second member having a second connection end and a second filtering characteristic, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, with the second connection end defining a first groove extending circumferentially around the second connection end with a first seal member residing in the first groove, wherein at least a portion of the second connection end is positioned in the riser with the first seal member engaging the straight portion of the riser, wherein at least a portion of the first member extends toward the first stage, wherein at least a portion of the second member extends toward the second stage, and wherein the first filtering characteristic and the second filtering characteristic are the same or different, the method may include separating the first member from the second member, while the filter element is positioned in the riser, thereby leaving at least a portion of the second member extending into the second stage. 
     According to even still another embodiment of the present invention, there is provided a method of operating a filtering apparatus, wherein the filtering apparatus comprises a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages, a riser extending from the opening, said riser having a first end with a straight portion and a second end with a flared portion, with the straight portion positioned nearer the opening than the flared portion, and further comprises a filter element positioned in the riser comprising a first member having a first end and a first filtering characteristic and a second member having a second connection end and a second filtering characteristic, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end engage to provide the connection, with the second connection end defining a first groove extending circumferentially around the second connection end with a first seal member residing in the first groove, wherein at least a portion of the second connection end is positioned in the riser with the first seal member engaging the straight portion of the riser, wherein at least a portion of the first member extends toward the first stage, wherein at least a portion of the second member extends toward the second stage, and wherein the first filtering characteristic and the second filtering characteristic are the same or different, the method may include replacing the first member with a replacement member. 
     According to even yet another embodiment of the present invention, there is provided an apparatus for filtering a gas. The apparatus may include a vessel having a partition dividing the vessel into a first stage and a second stage, wherein the partition defines an opening providing liquid communication between the stages. The apparatus may also include a riser extending from the opening, said riser having a first end with a straight portion and a second end with a flared portion, with the straight portion positioned nearer the opening than the flared portion. The apparatus may include a filter element having at least a portion positioned in the riser, the filter element comprising a first member having a first connection end and a first filtering characteristic, and a second member having a second connection end and a second filtering characteristic, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, with the second connection end defining first and second grooves extending circumferentially around the second connection end with a first seal member residing in the first groove and a second seal member residing in the second groove, wherein at least a portion of the second connection end is positioned in the riser with both the first and second seal members engaging the straight portion of the riser, wherein at least a portion of the first member extends toward the first stage, and at least a portion of the second member extends toward the second stage, wherein the first member is removable from the second member while the filter element is positioned in the opening, and wherein the first filtering characteristic and the second filtering characteristic are the same or different. 
     According to still even another embodiment of the present invention, there is provided a filter system that may include a riser having a first end with a straight portion and a second end with a flared portion. The system may include a filter element having at least a portion positioned in the riser the filter element comprising a first member having a first connection end and a first filtering characteristic, and a second member having a second connection end and a second filtering characteristic, wherein the first and second members are connected by a connection system in which the first connection end and the second connection end form a mating pair to provide the connection, with the second connection end defining a first groove extending circumferentially around the second connection end with a first seal member residing in the first groove, wherein at least a portion of the second connection end is positioned in the riser with the first seal member engaging the straight portion of the riser, wherein the first member is removable from the second member while the filter element is positioned in and remains in the riser, and wherein the first filtering characteristic and the second filtering characteristic are the same or different. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following drawings illustrate some of the many possible embodiments of this disclosure in order to provide a basic understanding of this disclosure. These drawings do not provide an extensive overview of all embodiments of this disclosure. These drawings are not intended to identify key or critical elements of the disclosure or to delineate or otherwise limit the scope of the claims. The following drawings merely present some concepts of the disclosure in a general form. Thus, for a detailed understanding of this disclosure, reference should be made to the following detailed description, taken in conjunction with the accompanying drawings, in which like elements have been given like numerals. 
         FIG. 1  is a schematic representation of one non-limiting embodiment of a filtration system of the present invention. 
         FIG. 2  is a schematic representation of a filter element of the present invention. 
         FIG. 3  shows engaging member  139  of first filter member  124  resides in slot  136  of second filter member  125 . 
         FIG. 4  shows first filter member  124  and second member  125  have been twisted relative to each other to allow engaging member  139  to move in slot  136  toward slot opening  137  to allow for disengagement. 
         FIG. 5  shows first filter member  124  and second member  125  have been further twisted relative to each other, such that engaging member  139  is shown aligned in slot opening  137  to allow for disengagement. 
         FIG. 6  shows first filter member  124  and second member  125  have been moved away from each other, such that engaging member  139  is shown moving though slot opening  137  to allow for disengagement. 
         FIG. 7  shows first filter member  124  and second member  125  have been moved away from each other, such that engaging member  139  is shown moved completely through slot opening  137  and filter members  124  and  125  are disengaged. 
         FIGS. 8-10  show slightly different views of filter  120 , showing filter members  124  and  125  disengaged. 
         FIG. 11  is an illustration of a non-limiting embodiment of the present invention, showing first filtration element  124 , second filtration element  125 , vessel partition  108  defining passage  111 , and filtration receiving tube  300  having a flared portion  301  and a straight portion  302 . 
         FIG. 12  is a schematic representation of receiving tube  300  and second pair member  135  having a sealing member  307  engaging the flared portion  301  of tube  300 . 
         FIG. 13  is a schematic representation of receiving tube  300  and second pair member  135  having two sealing members  307  engaging the flared portion  301  of tube  300 . 
         FIG. 14  is a schematic representation of receiving tube  300  and second pair member  135  having a sealing member  308  engaging the straight portion  302  of tube  300 . 
         FIG. 15  is a schematic representation of receiving tube  300  and second pair member  135  having a sealing member  307  engaging the flared portion  301  of tube  300 , and sealing member  308  engaging the straight portion  302  of tube  300 . 
         FIG. 16  is a schematic representation of receiving tube  300  and second pair member  135  having two sealing members  308  engaging the straight portion  302  of tube  300 . 
         FIG. 17  is a schematic representation of receiving tube  300  and second pair member  135  having sealing member  309  engaging the outer lip portion  310  of tube  300  and bottom edge portion of member  135 A. 
         FIG. 18  is a schematic representation of receiving tube  300  and second pair member  135  (shown on end of filter member  125 ) not quite engaged with tube  300 . This non-limiting embodiment shows sealing members  307 ,  308  and  309 , although other embodiments may have any combinations/numbers of these sealing members. 
         FIG. 19  shows receiving tube  300  engaged with second pair member  135  of  FIG. 18 . 
         FIG. 20  is a schematic representation of receiving tube  300  and second pair member  135  having sealing member  309  engaging the outer lip portion  310  of tube  300  and bottom edge portion of member  135 A. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In one aspect, the present invention provides a filtration filter. In another aspect, the present invention provides a filtration system that includes the filtration filter positioned within a filtration vessel. Any suitable type of filtration vessel may be utilized in the practice of the present invention, including certain filtration vessels as disclosed in any of U.S. Pat. Nos. 5,919,284, 6,187,647, 7,014,685, and 7,108,738. Depending upon the situation and operating conditions, suitable filtration vessels may include multi-stage vessel 11 as shown in FIG. 1 of U.S. Pat. No. 6,187,647, and filter vessel 13 as shown in FIG. 1 of U.S. Pat. No. 7,014,685, with the understanding that vessels 11 and 13 will include the filtration filter as disclosed herein, and be adapted to receive such filter. 
     Referring now to  FIG. 1 , there is shown a schematic representation of one non-limiting embodiment  100  of the filtration system of the present invention. In very simple terms, the filtration system of the present invention may include a filtration vessel  102  having a first stage  104  and a second stage  105 . A partition  108  positioned within filtration vessel  102  divides the volume of filtration vessel  102  into first stage  104  and second stage  105 . The present invention anticipates that in some non-limiting embodiments, filtration vessel may comprise two vessels that are joined together, one vessel forming the first stage, and one vessel forming the second stage, with the abutted walls of each vessel serving as the partition, or perhaps the two vessels will share a common wall serving as the partition. 
     Partition  108  defines at least one passage  111  allowing for liquid communication between first stage  104  and second stage  105 . Within each of passages  111  will reside a filtration filter  120 . This filter  120  includes at least two distinct parts, first filtration member  124  and second filtration member  125 . Filter member  120  may in some embodiments be a hollow core filtration filter. In some non-limiting embodiments, at least a portion of first filtration member  124  will extend into vessel first stage  104 , and at least a portion of first member  124  will extend into vessel second stage  105 . In some non-limiting embodiments, none of first filtration member  124  will extend into vessel second stage  105 . In even other embodiments, none of the second filtration member  125  will extend into vessel second stage  105 . In even further non-limiting embodiments, an additional filter element, such as a liquid impingement baffle, will be placed over the second filtration member  125 . 
     It should be understood that first filtration member  124  and second filtration member  125  may provide the same or different filtering, that is, the filtering characteristic of the first and second filtration members  124  and  125  may be the same or different. As a non-limiting example, first filtration member  124  may have a first filtering characteristic wherein it removes larger particles and allows smaller particles to be removed by filtration member  125  having a second filtering characteristic wherein it removed smaller particles. It should also be understood that when multiple filter members  120  are utilized, each of the multiple filter members  124  and  125  may be the same or different. As a non-limiting example, various same and/or different filter members  120  may be utilized based on the geometry of the arrangement of the filter members  120 , based on the geometry of the vessel  102 , and/or based on any other operating parameter or physical property of the material being filtered. It should also be understood that filter member  120  may also include multiple stages that align with multiple stages in a vessel  102 . The filter member  120  may include mating pairs  130  at the interface of one or more or all of the interfaces between stages, which mating pairs  130  may be the same or different, and this filter member  120  may be disconnectable at one or more the mating pairs  130 . 
     Filtration vessel  102  further includes an inlet port  184  in fluid communication with vessel first stage  104 . Filtration vessel  102  even further includes an outlet port  185  in fluid communication with vessel second stage  105 . 
     Gas flow, indicated by the “G” labeled arrows, is through inlet port  184  and into vessel first stage  104 , through the filter wall of filter member  124 , through the hollow core of filter member  124 , into the hollow core of filter member  125 , out through the wall of filter member  125 , through the second stage  105 , and finally exiting through outlet  185 . 
     Referring additionally to  FIG. 2 , there is shown a schematic representation of filter element  120  of the present invention. Referring even additionally to  FIGS. 3-10 , there is illustrated various views of filter element  120  showing first member  124  and second member  125  in various states of connection. Filter member  124  and filter member  125  are joined by a mating pair  130  having a first pair member  134  at end  124 A of filter member  124 , and a second pair member  135  at end  125 A of filter member  125 . In some embodiments, the mating pair  130  will comprise male and female connector members. It should be understood that first pair member  134  may comprise either a male or female connector member, with second pair member  135  comprising the complimentary mating female or male connector member. In most embodiments, a female-male arrangement for the first and second pair members  134  and  135  will be considered equivalent to a male-female arrangement. This mating pair  130  must sufficiently join filter member  124  and  125  together so as to endure the hardships of the filtration operation, but must allow disconnecting of filter member  124  to allow for removal of such filter member  124 . As non-limiting examples, mating pair  130  may connect by snapping, bolting, friction fitting, interlocking, engaging, coupling, hook/looping, adhering, adhesion with a time released adhesive, adhesion with a solvent releasing adhesive, magnetic coupling, locking, threadably engaging, and the like. 
     In  FIG. 3 , engaging member  139  of first filter member  124  resides in slot  136  of second filter member  125 . As shown, engaging member  139  resides in end  138  of slot  136 . Generally, twisting/untwisting of members  124  and  125  relative to each other would lock engaging member  139  in place at end  138  or could move it toward slot opening  137  for disengagement. As a non-limiting embodiment, end  138  of slot  136  may be shaped (for example tapered) to provide a friction fit of engaging member  139 , or the surfaces of slot  136  at end  138  may be textured/roughened to engage textured/roughened surfaces of engaging member  139 . Untwisting them will reverse the process and allow for the members to be separated. 
     Referring now to  FIG. 4 , first filter member  124  and second member  125  have been twisted relative to each other to allow engaging member  139  to move in slot  136  toward slot opening  137  to allow for disengagement. 
     Referring now to  FIG. 5 , first filter member  124  and second member  125  have been further twisted relative to each other, such that engaging member  139  is shown aligned in slot opening  137  to allow for disengagement. 
     Referring now to  FIG. 6 , first filter member  124  and second member  125  have been moved away from each other, such that engaging member  139  is shown moving though slot opening  137  to allow for disengagement. 
     Referring now to  FIG. 7 , first filter member  124  and second member  125  have been moved away from each other, such that engaging member  139  is shown moved completely through slot opening  137  and filter members  124  and  125  are disengaged. 
       FIGS. 8-10  show slightly different views of filter  120 , showing filter members  124  and  125  disengaged. 
     In methods of the present invention, with filter element positioned within a filter vessel  102 , filter member  124  may be separated from filter member  125 , removed from vessel  102 , and then replaced with a new filter member. 
     Referring now to  FIG. 11 , there is illustrated a non-limiting embodiment of the present invention, showing first filtration element  124 , second filtration element  125 , vessel partition  108  defining passage  111  connecting first stage  104  and second stage  105 , and filtration receiving tube  300  having a flared portion  301  and a straight portion  302 . End  125 A of second filtration element  125  is inserted into filtration receiving tube  300  with mating pair member  135  on the other end of element  125  engaging flared portion  301 , with sealing members  307  and  308  providing sealing against tube  300 . In some embodiments, all of mating pair member  135  may be inserted into tube  300 . In other embodiments, a first portion of mating pair member  135  is inserted into tube  300 , with a second portion of mating pair member  135  not inserted into tube  300 . This second portion of mating pair member  135  is generally larger than tube  300  cross-sectional area and actually wedges against end of tube  300  and is unable to be inserted into tube  300 . First filtration element  124  engages second filtration element  125  as described above, with mating pair members  134  and  135  engaging. Mating pair member  135  may have groove(s)  307 A for receiving sealing member(s)  307  and groove(s)  308 A for receiving sealing member(s)  308 . In some embodiments, it is possible or second filtration element  125  to reside in tube  300  and not extend past partition  108 , although for many embodiments, filtration element  125  will extend past partition  108  and into second stage  105 . Regarding passage  111 , in various non-limiting embodiments, it may be regarded as being defined by vessel partition  108  with filtration receiving tube  300  positioned therein, or passage  111  may be regarded as defined by receiving tube  300  which passes through vessel partition  108 , or passage  111  may be in communication with the end of receiving tube  300  with tube  300  abutted against partition  108 , or an integral unit may define partition  108 , filtration receiving tube  300  and passage  111 , or any combination thereof. 
     The filtration receiving tube  300  is generally a riser member that is affixed to vessel partition  108  positioned generally over passage  111 . In many embodiments, vessel partition  108  will define numerous passages  111 , and risers will generally be positioned over each of the numerous passages  111 . Certainly, it is possible to construct a filtration vessel  102  with a vessel partition  108  having integral risers, rather than having risers that are subsequently affixed. However, very commonly commercial filtration vessels generally includes riser members as the filtration receiving tube  300  that have been affixed, usually by welding techniques, over each of the passages  111  on vessel partition  108 . 
     These risers  300  will generally have a slightly flared end  301 . While not being limited by theory, applicants believe that in some (but not all) instances, the flared portion  301  may provide a less consistent, less reliable sealing surface than the straight portion  302 . 
     While not wishing to be limited by theory, applicants believe that problems in sealing may be caused by at least two mechanisms. In some instances this flared portion  301  is not quite as round as the straight portion  302 , and when engaged with round member  135  some portions of the seal around member  135  will engage more or less depending upon the larger or smaller gap between the less than round flared portion  301  and the more round member  135 . Thus, various non-limiting embodiments of the present invention provide for 2 or more sealing elements in the flared portion, or at least one sealing element in the straight portion, or at least one sealing element in each of the flared and straight portions. In other instances, a local surface inconsistency may cause sealing issue. These problems with less than round flared portions  301  and surface inconsistencies may be addressed by positioning the seal member in the straight portion  302  as it is likely to be more round and/or by using redundant sealing members positioned either in the flared or straight portions. 
     Sealing member  307  is understood to be a sealing element that engages the flared portion  301  of filtration receiving tube  300 , and sealing member  308  is understood to be a sealing element that engages the straight portion  302  of filtration receiving tuber  300 . While both sealing members  307  and  308  are shown, it is understood that second filtration element  125  may have only sealing member(s)  307 , or only sealing member(s)  308 , or any numbers of both sealing members  307  and  308 . 
     Sealing members  307  and  308  may be any suitable sealing member/material that will provide suitable sealing between member  125  and riser  300 . A non-limiting examples of a suitable sealing member includes a packing joint, which is a mechanical gasket with a suitable cross-section, designed to be seated in grooves  307 / 308  and compressed between riser  300  and mating pair member  135  upon insertion and seating of member  125  into riser  300 . 
     Non-limiting examples packing joints suitable for use as the sealing means include those having any suitable cross-sectional shapes, include round, oval, X, square, triangular, U, or any other regular or irregular geometric shape as the cross-section. Non-limiting embodiments of the present invention may utilize U seals. 
     Referring additionally to  FIG. 12 , there is shown a schematic representation of receiving tube  300  and second pair member  135  having a sealing member  307  engaging the flared portion  301  of tube  300 . 
     Referring additionally to  FIG. 13 , there is shown a schematic representation of receiving tube  300  and second pair member  135  having two sealing members  307  engaging the flared portion  301  of tube  300 . 
     Referring additionally to  FIG. 14 , there is shown a schematic representation of receiving tube  300  and second pair member  135  having a sealing member  308  engaging the straight portion  302  of tube  300 . 
     Referring additionally to  FIG. 15 , there is shown a schematic representation of receiving tube  300  and second pair member  135  having a sealing member  307  engaging the flared portion  301  of tube  300 , and sealing member  308  engaging the straight portion  302  of tube  300 . 
     Referring additionally to  FIG. 16 , there is shown a schematic representation of receiving tube  300  and second pair member  135  having two sealing members  308  engaging the straight portion  302  of tube  300 . 
     Referring additionally to  FIG. 17  there is shown is a schematic representation of receiving tube  300  and second pair member  135  having sealing member  309  engaging the outer lip portion  310  of tube  300  and bottom edge portion of member  135 A. 
     Referring additionally to  FIG. 18  there is shown a schematic representation of receiving tube  300  and second pair member  135  (shown on end of filter member  125 ) not quite engaged with tube  300 . This non-limiting embodiment shows sealing members  307 ,  308  and  309 , although other embodiments may have any combinations/numbers of these sealing members. Moving forward,  FIG. 19  shows receiving tube  300  engaged with second pair member  135  of  FIG. 18 . 
     Referring additionally to  FIG. 20  there is shown is a schematic representation of receiving tube  300  and second pair member  135  having sealing member  309  engaging the outer lip portion  310  of tube  300  and bottom edge portion of member  135 A. While similar to  FIG. 17 , this sealing member  309  is shaped to drape over outer lip portion  310  and drape down onto the tapered and even possibly the straight portion of tube  300 . 
     All of the patents and applications cited in this specification, are herein incorporated by reference. 
     It should be understood that while the present invention has been illustrated mainly by reference to filtration of a gas stream, it finds utility in the filtration of gas streams, liquid streams, and gas/liquid streams. 
     The present disclosure is to be taken as illustrative rather than as limiting the scope or nature of the claims below. Numerous modifications and variations will become apparent to those skilled in the art after studying the disclosure, including use of equivalent functional and/or structural substitutes for elements described herein, use of equivalent functional couplings for couplings described herein, and/or use of equivalent functional actions for actions described herein. Any insubstantial variations are to be considered within the scope of the claims below.