The present disclosure relates generally to the field of sterilization and/or viral inactivation devices, systems, and methods. In particular, the present disclosure relates to high-temperature short-term (HTST) treatment devices, systems, and methods, such as for viral inactivation.
The use of heat for various sterilization processes has long been known in the art for various applications, such as pasteurization and viral inactivation. Heat exchangers are devices that allow heat from a hot fluid to pass to a second fluid without the two fluids having to mix together or come into direct contact. The principle of a heat exchanger relies on two fluid streams isolated from each other using a thermally conductive barrier therebetween. The thermally conductive barrier allows heat to be transferred from the hot fluid to the second fluid to be heated.
Heat inactivation, and, particularly, high-temperature short-time (HTST) treatment, which may utilize heat exchangers, has been evaluated by various biologics manufacturers as a potential upstream barrier technology for mitigating the risk of introducing adventitious viral contaminants into biological process streams. More particularly, HTST treatment has been evaluated for use in mitigating the risk of introducing adventitious viral contaminants into manufacturing processes via contaminated cell-culture reagents and other process solutions. Such treatment is generally considered to represent an efficacious and robust risk mitigation step for the inactivation of virus.
HTST treatment has additional commercial benefits in that it is generally a continuous process. As such, HTST treatment may be integrated into another continuous process such that a continuous purification process, which is particularly advantageous in a commercial setting, is easily accomplished.
More recently, single-use technologies, such as bioreactors for cell culture, tangential-flow filtration (TFF) systems for harvest, and other disposable technology options for many types of processing, such as in the biopharmaceutical industry, are being adopted. It may be desirable or advantageous to include HTST treatment with such processing. However, traditional heat exchangers are not ideally suited for a single-use continuous viral inactivation step. Without a viable high capacity single-use heat exchanger, process engineers have been forced to choose one of two options which are currently considered less than ideal. The first option is to insert a stainless-steel multiuse heat exchanger into the process. Typically, two discrete conventional heat exchangers constructed of stainless steel are used for HTST treatment, which would not address single-use applications desirable in the biopharmaceutical market. This option sacrifices the benefits of a full single-use set up, resulting in prolonged downtime (such as to sterilize the heat exchanger between processes), and expensive capital equipment. The second option is to use a jacketed mixing tote in place of a heat exchanger. The sacrifice accompanying this option is in terms of rate of heat transfer—jacketed mixing totes have not been designed for rapid temperature control. As such, neither of these solutions is ideal for a single use HTST application. Each has brought a series of problems for which the industry has had to contend with.
In view of the above, an economical HTST treatment device, system, and method would be welcome in the industry. In addition or alternatively, an HTST treatment device, system, and method configured and designed to be disposable and/or for single-use (such terms may be used interchangeably herein without intent to limit) applications, such as in the biopharmaceutical industry, would be welcome in the industry. In addition or alternatively, an HTST treatment device, system, and method which may be readily integrated into a continuous manufacturing process requiring heat inactivation at at least one stage of the process would be welcome in the industry.
In one aspect, the present subject matter is directed to a heat exchanger having a heating section defining flow paths for heating medium along flow paths for a process stream, and a cooling section thermally and physically isolated from said heating section and defining flow paths for cooling medium along flow paths for a process stream. The heating medium flow paths are physically isolated from and thermally coupled with the process stream flow paths, and, similarly, the cooling medium flow paths are physically isolated from and thermally coupled with the process stream flow paths. The heat exchanger, as a single unit, includes process stream ports, heating medium ports, and cooling medium ports.
In some embodiments, a manifold is coupled to the heat exchanger, the manifold comprising, as a unit, manifold process stream ports corresponding to and in fluid communication with the heat exchanger process stream ports, manifold heating medium ports corresponding to and in fluid communication with the heat exchanger heating medium ports, and manifold cooling medium ports corresponding to and in fluid communication with the heat exchanger cooling medium ports, such that a process stream flows continuously through the heating section to the cooling section through the manifold.
In some embodiments, the manifold receives the process stream that has been heated through the heating section of the heat exchanger, transfers the heated process stream to the cooling section of the heat exchanger, and receives the process stream that has cooled through the cooling section of the heat exchanger.
In some embodiments, the heat exchanger of is a single unit and the manifold is a single unit mating with the heat exchanger single unit.
In some embodiments, the heat exchanger further comprises a plurality of stacked channel spacers defining the flow paths through the heat exchanger. In some further embodiments, the plurality of channel spacers seal fluid within the heat exchanger and isolate flow paths within the heat exchanger. In some further embodiments, each channel spacer defines the flow paths in the heating section and the cooling section of the heat exchanger. In some further embodiments, each channel spacer comprises a frame element and a flow element, wherein frame elements of stacked channel spacers are bonded together to form a peripheral seal about the heat exchanger as a unit and an insulative wall between the heating section and the cooling section within the heat exchanger.
In one aspect, the present subject matter is directed to a heat exchanger configured to be a single-use and/or disposable unit, with a plurality of channel spacers stacked together, each channel spacer defining a fluid flow channel for a fluid medium to flow therethrough; and a thermally conductive physical barrier, in the form of thin foil or film, sandwiched between adjacent channel spacers to conduct thermal energy between fluid mediums in adjacent channel spacers while physically isolating the fluid mediums from each other.
In some embodiments, the thermally conductive physical barrier is sufficiently thin to allow at least ten thermally conductive physical barrier in said heat exchanger without impeding on unassisted manual portability of said heat exchanger (a greater number of thermally conductive physical barriers than could normally be provided in a prior art heat exchanger not designed for single-use or to be disposed of or discarded). Each thermally conductive physical barrier may, in some embodiments, be no greater than 0.010″ (0.254 mm) thick. In some embodiments, each thermally conductive physical barrier is in the form of a thin foil or film that cannot maintain structural rigidity and shape unassisted. In some further embodiments, the channel spacers provide structural rigidity to the thermally conductive physical barriers.
In some embodiments, each channel spacer comprises a frame element and a screen element. In some further embodiments, each channel spacer further comprises a seal element sealing fluid flow between the frame element of the channel spacer, an upper thermally conductive physical barrier on one side of the channel spacer, and a lower thermally conductive physical barrier on an opposite side of the channel spacer.
In accordance with additional aspects of the present disclosure, the present subject matter is directed to a method of heating and cooling a process stream through a single heat exchanger unit along a continuous flow path using a thermal medium comprising a heating medium or a cooling medium. In accordance with some aspects, the method comprises providing a at least one process stream heating medium flow path and at least one heating medium flow path through a heating section of the single heat exchanger, the heating medium flow path extending along a process stream heating flow path to heat the process stream, and providing a at least one process stream cooling flow path and at least one cooling medium flow path through a cooling section of the single heat exchanger, the cooling medium flow path extending along a process stream cooling flow path to cool the process stream, wherein heating and cooling of a process stream is achieved in the same single heat exchanger.
In some embodiments, the method further comprises providing a plurality of system ports in the single heat exchanger, the system ports including process stream ports in fluid communication with the process stream flow paths through the single heat exchanger, and thermal medium ports in fluid communication with heating medium flow paths and cooling medium flow paths in the single heat exchanger.
In some embodiments, the method further comprises coupling the single heat exchanger with a mating manifold configured to distribute flow to the system ports in the single heat exchanger. In some embodiments, the manifold is provided with inlet and outlet ports for passage of process stream, a heating medium, and a cooling medium into or out of the manifold and thus the single heat exchanger.
In some embodiments, the method further comprises coupling the single heat exchanger to a mating manifold, the manifold transferring the process stream from the heating section to the cooling section of the single heat exchanger.
These and other features and advantages of the present disclosure will be readily apparent from the following detailed description, the scope of the claimed invention being set out in the appended claims.
This summary of the disclosure is given to aid understanding, and one of skill in the art will understand that each of the various aspects and features of the disclosure may advantageously be used separately in some instances, or in combination with other aspects and features of the disclosure in other instances. No limitation as to the scope of the claimed subject matter is intended by either the inclusion or non-inclusion of elements, components, or the like in this summary. Accordingly, while the disclosure is presented in terms of aspects or embodiments, it should be appreciated that individual aspects can be claimed separately or in combination with aspects and features of that embodiment or any other embodiment.
The detailed description will be better understood in conjunction with the accompanying drawings, wherein like reference characters represent like elements, as follows:
Non-limiting embodiments of the present disclosure are described by way of example with reference to the accompanying drawings, which are schematic and not intended to be drawn to scale. The accompanying drawings are provided for purposes of illustration only, and the dimensions, positions, order, and relative sizes reflected in the figures in the drawings may vary. In the figures, identical or nearly identical or equivalent elements are typically represented by the same reference characters. For purposes of clarity and simplicity, not every element is labeled in every figure, nor is every element of each embodiment shown where illustration is not necessary to allow those of ordinary skill in the art to understand the disclosure.
The following detailed description should be read with reference to the drawings, which, as noted above, depict illustrative embodiments. It will be appreciated that the present disclosure is set forth in various levels of detail in this application. In certain instances, details that are not necessary for one of ordinary skill in the art to understand the disclosure, or that render other details difficult to perceive may have been omitted. All of the devices and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. It should be understood that the claimed subject matter is not necessarily limited to the particular embodiments or arrangements described or illustrated herein, the scope of the claimed invention being set out in the appended claims.
Various embodiments of an HTST treatment device, system, and method will now be described. Reference in this specification to “one embodiment,” “an embodiment,” “some embodiments”, “other embodiments”, etc. indicates that one or more particular features, structures, and/or characteristics in accordance with principles of the present disclosure may be included in connection with the embodiment. However, such references do not necessarily mean that all embodiments include the particular features, structures, and/or characteristics, or that an embodiment includes all features, structures, and/or characteristics. Some embodiments may include one or more such features, structures, and/or characteristics, in various combinations thereof. Moreover, references to “one embodiment,” “an embodiment,” “some embodiments”, “other embodiments”, etc. in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments necessarily mutually exclusive of other embodiments. When particular features, structures, and/or characteristics are described in connection with one embodiment or component, it should be understood that such features, structures, and/or characteristics may also be used in connection with other embodiments or components whether or not explicitly described, unless clearly stated to the contrary. It should further be understood that such features, structures, and/or characteristics may be used or present in various combinations with one another to create alternative embodiments which are considered part of the present disclosure, as it would be too cumbersome to describe all of the numerous possible combinations and subcombinations of features, structures, and/or characteristics. Moreover, various features, structures, and/or characteristics are described which may be exhibited by some embodiments and not by others. Similarly, various features, structures, and/or characteristics or requirements are described which may be features, structures, and/or characteristics or requirements for some embodiments but may not be features, structures, and/or characteristics or requirements for other embodiments.
In accordance with various principles of the present disclosure, a device, system, and method for HTST treatment, such as for viral inactivation, may provide one or more benefits including cost-effectiveness; capability of continuous processing/being integrated into a continuous process; single-use configuration; and/or disposable configuration. The present disclosure provides, at least in some embodiments, a cost effective, single-use HTST device and process useful in achieving continuous HTST viral inactivation in a biopharmaceutical process. Sterilization or viral inactivation performed in accordance with or with devices or systems of the present disclosure may be particularly useful in biopharmaceutical processes in which retrieval of a process stream (e.g., stream of fluid in an overall process such as a purification train, including, inter alia, centrifuge, filter, chromatography, column, and other process, without limitation) in a short amount of time is desired. The device, system, and process disclosed herein utilizes a unique heat exchanger. Optionally, the device, system, and process disclosed herein utilizes a unique manifold in conjunction with the heat exchanger. It will be appreciated that principles applied to the heat exchanger and manifold components of the system described herein may be applied independently to heat exchangers and/or manifolds whether or not used in conjunction with an HTST process.
The principle of a heat exchanger relies on two fluid streams isolated from each other by a thermally conductive physical barrier. The barrier allows thermal energy to be transferred between the fluid streams. In accordance with one aspect of the present disclosure, the process stream is rapidly heated and then rapidly cooled to inactivate viral components or other pathogens or contaminants therein. Such heating and cooling, in accordance with one aspect of the present disclosure, takes place in a single heat exchanger or cassette housing a heating section as well as a cooling section. In a separate and independent aspect of the present disclosure, which may be independent from or in conjunction with the aforementioned aspect, such heating and cooling is a continuous process. For instance, flow into the device is equal to the flow out of the device, and the fluid flow does not have to stop or pause within a given processing device. In yet another separate and independent aspect of the present disclosure, which may be independent from or in conjunction with either of the aforementioned aspects, heating and cooling of a process stream is performed along a single flow path for the process stream, such flow path optionally being a continuous single flow path. In yet another separate and independent aspect of the present disclosure, which may be independent from or in conjunction with any of the aforementioned aspects, such heating and cooling is performed in a device configured and formed for a single use and/or to be disposable.
In accordance with one aspect of the present disclosure, a dual path heat exchanger is integrated into a single unit capable of processing a fluid stream starting at a temperature of as low as about 4° C. and as high as about 25° C. The heat exchanger is connected to a heat pump and a chiller which separately pass a thermal medium (e.g., glycol) into the heat exchanger in flow paths which are physically isolated from yet in thermal communication with the process stream flow path. More specifically, a hot medium (heated by an associated heating system) is passed through a heating section of the heat exchanger, and a cold medium (cooled by an associated cooling system) is passed through a cooling section of the heat exchanger. The medium to be processed by the heat exchanger (hereinafter, the “process stream” for the sake of simplicity and without intent to limit), such as a biological process stream, enters the heat exchanger via an inlet port and flows along a process stream heating flow path (optionally referenced as a “heated” or “hot” process stream flow path without intent to limit) through the heating section of the heat exchanger. The process stream and the hot medium (optionally referenced herein as “heating” or “heated” medium without intent to limit) are in thermal communication (and preferably physically/fluidly isolated) so that the process stream is rapidly heated to the desired temperature (e.g., approximately 70° C.-85° C. for typical applications). The process stream is held for a short period of time at an elevated temperature (e.g., over about 10 seconds) as it flows through the manifold from one side to the other. This hold time generally is determined by the flow rate and the size of the bore in the manifold. Thermocouples or temperature probes may be placed in the manifold to monitor the internal temperatures. The process stream then enters a cooling section (preferably thermally isolated from the heating path) in the heat exchanger and flows along a process stream cooling flow path (optionally referenced as a “cooled” or “cold” process stream flow path without intent to limit). The process stream and the cold medium (optionally referenced herein as “cooling” or “cooled” medium without intent to limit) are in thermal communication (and preferably physically/fluidly isolated) so that the process stream is rapidly cooled to the desired temperature (e.g., the initial starting temperature). In some embodiments, the heat exchanger flow paths includes one or more of the following components: a channel for fluid flow (for at least one of the process stream, the hot medium, or the cold medium); a turbulence promoter; and a thermally conductive material.
In some embodiments, the fluid flows are substantially planar (such as in a plate and frame heat exchanger) and separated by a thermally conductive physical barrier. In some embodiments, the barrier is in the form of a thin material, such as a polymeric film or foil, so that the heat exchanger is more amenable for ready disposal (is commonly considered disposable and for single use applications) in contrast with larger or heavier equipment with thicker walls (e.g., stainless steel walls as commonly used in prior art heat exchangers). Such single-use design/construction reduces the risk of cross-contamination from batch to batch, and thus is considered safer than prior art techniques, and particularly beneficial for drug manufacturing applications. A single-use heat exchanger is generally considered to be “ready to process” technology. For instance, because a single-use heat exchanger is not reused, it may be initially sterile and ready for use (unlike traditional heat exchangers which need to be autoclaved or otherwise sterilized). Moreover, a single-use, continuous process allows implementation of HTST viral inactivation not heretofore achievable with existing heat exchangers.
In accordance with some aspects of the present disclosure, the heating and cooling paths are in the same heat exchanger unit, simplifying the application over prior art heat exchangers which typically are constructed with a single path of the same thermal nature (either a single heating path or a single cooling path) and thus would require two separate units coupled together to provide the desired heating and cooling. In particular, a single heat exchanger unit containing both a heating path or section and a cooling path or section, as disclosed herein, is better adapted for HTST use than conventional heat exchangers, such as by providing heating and cooling in the same unit, and simplified construction and configuration over a more complex construction typically resulting from use of separate units for heating and cooling. In addition, provision of the heating path and cooling path in the same heat exchanger unit permits a single continuous flow path for the process stream. The process stream flows continuously from a heating section to a cooling section, and the flow is not interrupted by transport or waiting times in separate heating equipment and cooling equipment. In some embodiments, discussed in greater detail below, the process stream may flow through a manifold between the heating section and the cooling section of the heat exchanger, allowing the process stream to maintain an elevated temperature and flow continuously between the heating section and the cooling section.
In some embodiments, the heating path and the cooling path are substantially parallel to each other. In some embodiments, the flow direction of the process stream through the heating path is opposite the flow direction of the process stream through the cooling path. Such arrangement may allow for a more compact design. In some embodiments, independent of the relative positioning of the heating path and cooling path, the flow direction of the process stream is opposite the flow direction of the associated/adjacent thermal medium (the heating medium or the cooling medium). Such arrangement and counter current flow may allow for more efficient and maximized thermal transfer.
A heat exchanger system in accordance with the present disclosure may include a heat exchanger configured similar to a plate and frame heat exchanger, used in combination with a manifold, with clamping plates holding together the heat exchanger and manifold. The manifold may be a flow distribution manifold configured to direct the various fluid medium flows through the fluid paths of the heat exchanger. System ports (for flow of fluid within the system, and, in some embodiments facing the heat exchanger) in the manifold are in fluid communication with corresponding ports in the heat exchanger to allow the process stream and the thermal mediums (hot medium and cold medium) to flow from/to the respective heating and cooling sections of the heat exchanger, and be respectively distributed/collected by the manifold (e.g., distributed to the heating section; collected from the heating section; held in the transfer section; distributed to the cooling section; collected from the cooling section; etc.). Auxiliary ports in the manifold (e.g., on the side/periphery of the manifold) are provided for flow of medium into and out of the system (e.g., flow of process stream into or out of the heat exchanger from a source external to the manifold; or flow of thermal medium, heated or cooled by separate equipment, into the manifold for distribution to one of the heating or cooling sections of the heat exchanger; or flow of thermal medium away from the heat exchanger for reheating or recooling; etc.). As noted above, thermocouples or temperature probes may be used to monitor temperatures within the device to confirm the temperature requirements are met. In some embodiments, the manifold is manufactured from a single piece such as machined or molded plastic. As a single unit coupled to a single heat exchanger containing both a heating section and a cooling section, the manifold further contributes to the simplified design of the present disclosure, and the ability to provide a commercially viable continuous process for viral inactivation, such as via HTST treatment. The single unit also affords a cost savings over stainless steel and/or connecting two separate heat exchangers together.
Referring now to the drawings, an example of a heat exchanger 100 formed in accordance with principles of the present disclosure is shown in
An example of a fluid flow pattern of the process stream and thermal mediums flowing through a heat exchanger 100 as shown in
As illustrated schematically in
After reaching the opposite end of the heating section 110, the heated process stream exits the heating section 110 through the process stream heating section outlet port 113p and is transported to the cooling section 120. In one embodiment, the process stream is transported in a passage or channel (such as though a passage within a mating manifold in fluid communication with the heat exchanger 100, as described in further detail below) transverse to the heating medium flow path HFP, such as along a transfer flow dimension TFD of the heat exchanger 100 transverse to (e.g., perpendicular to) the flow path dimension FPD. This path allows the fluid stream to be held at an elevated temperature for a period of time and is dependent on the volume of the fluid path and flow rate of the process fluid. Generally, for viral inactivation, temperatures must remain elevated for at least about 10 seconds. The process stream enters the cooling section 120 at a process stream cooling section inlet port 121p and flows within the cooling section 120 along a process stream cooling flow path PCFP along (such as alongside, and particularly, such as parallel to) a cooling medium flow path CFP. Both paths may be described as extending along a flow path dimension FPD of the heat exchanger 100. A cooled or cooling or cold (such terms being used interchangeably without intent to limit) medium flows through the cooling medium flow path CFP to cool the process stream flowing through the cooling section 120. The process stream cooling flow path PCFP and the cooling medium flow path CFP are physically isolated, so that there is no comingling of mediums/fluids therebetween, yet in thermal communication so that the cooling medium flow path CFP cools the process stream flowing along the process stream cooling flow path PCFP. At the end of the process stream cooling flow path PCFP, the process stream is preferably at the desired cooled temperature and exits the heat exchanger 100 through the process stream cooling section outlet port 123p for collection and/or further processing.
The fluid flow pattern illustrated in
More particularly, as illustrated schematically in
Similarly, as illustrated schematically in
Various parameters, such as flow rate, heating section 110 and cooling section 120 dimensions, heating medium and cooling medium temperatures, heat exchanger 100 materials, etc., may be chosen to achieve a temperature change in the process stream, within the time frame required for the process stream to enter and exit the heat exchanger 100, sufficient to meet the requirements of HTST treatment to achieve the desired heat inactivation, such as by inactivating any viral components in the process stream.
In the illustrated embodiments, as in known plate and frame heat exchangers, the alternating flow paths within the heat exchanger 100 of the present disclosure are defined by a plurality of flow channels 106 (more particularly, as in the illustrated embodiments, stacks of substantially planar flow channels) through which fluid (process stream or thermal medium) moves. In one embodiment of a heat exchanger 100, the flow channels 106 include a fluid flow channel 107 (through which the process stream or thermal medium flows through the heating section 110 or cooling section 120 of the heat exchanger 100), and thermally conductive physical barriers 108 between the thermal mediums (heating medium or cooling medium) and the process stream. Optionally, a turbulence promoter is provided in the fluid flow channel 107 to optimize heat exchange. The thermally conductive physical barriers 108 physically isolate the thermal mediums (in thermal medium flow channels) from the associated process stream (in adjacent process stream flow channels) while conducting as much heat as possible between the streams to achieve the desired thermal exchange. In some embodiments, at least one heating medium flow path HFP is adjacent a process stream flow path PFP and transfers heat thereto so that the process stream flow paths PFP in the heating section 110 may all be considered process stream heating flow paths PHFP. In some embodiments, heating medium flow paths HFP may alternate with process stream flow path PFP, though other arrangements are within the scope of the present disclosure. Likewise, in some embodiments, at least one cooling medium flow path CFP in the cooling section 120 is adjacent a process stream flow path PFP so that process stream flow paths in the cooling section 120 may all be considered process stream cooling flow paths PCFP. In some embodiments, cooling medium flow paths CFP may alternate with process stream cooling flow paths PCFP, though other arrangements are within the scope of the present disclosure.
In the example of a heat exchanger 100 illustrated in
Examples of channel spacers 130 which may be used in the heat exchanger 100 of
The process stream flows co-currently through alternate fluid flow channels 107 through the channel spacers 130 in each of the heating section 110 and cooling section 120 with thermal medium flowing co-currently through alternate thermal medium fluid flow channels 107h, 107c between the process stream fluid flow channels 107p. As described above, the thermal mediums may flow counter-currently with respect to the process stream in a given heating/cooling section. In one embodiment, the seal element 134 is a fluid impermeable structure, such as an elastomer (e.g., a polymer such as high density polyethylene or polypropylene, polyurethane, EPDM rubber) or another thermoset or thermoplastic material (e.g., epoxy, silicone, etc.) formed into a barrier to direct a particular fluid medium into a given fluid flow channel 107 and to prevent mixing of adjacent fluid flows so that thermal mediums do not mix with the process stream. Because, as described above, thermal medium fluid flow channels 107h, 107c alternate with process stream fluid flow channels 107p, and different inlet and outlet ports 111p, 111h, 113p, 113h, 121p, 121c, 123p, and 123c are provided for or dedicated to different particular fluid flows, the positioning of the seal element 134 with respect to the ports 111p, 111h, 113p, 113h, 121p, 121c, 123p, and 123c alternate between adjacent channel spacers 130 to create alternating seals and thus alternating fluid flows through alternating fluid flow channel 107. As such, thermal mediums and process stream are isolated so only the process stream or the thermal medium (and not both) enters a given fluid flow channel 107, as may be appreciated with reference to
In order for heat exchanger 100 to effectively heat or cool the process stream, and in order to prevent mixing of fluid mediums between adjacent fluid flow channels 107, physical barriers 108 constructed of heat conductive materials, such as metals (e.g., stainless steel) or heat-conductive polymers (e.g., polymers utilizing heat-conductive additives such as graphite carbon fiber or ceramics such as aluminum nitride and boron nitride), are provided between adjacent channel spacers 130. In one embodiment, as illustrated in
The physical barriers 108 are formed of a material which prevents fluid flow therethrough, so that when a physical barrier 108 is placed along a channel spacer 130, fluid is retained in that channel spacer 130. In order to allow fluid to be distributed to the fluid flow channels 107 defined by the channel spacers 130 in the heat exchanger 100, the physical barriers 108 between the channel spacers 130 include ports similar to and corresponding with the ports provided in the channel spacers 130 to allow fluid mediums to flow therethrough (e.g., vertically, or perpendicular to the plane of the physical barrier 108) to the channel spacers 130 through which the fluid mediums are to flow (e.g., horizontally or along the plane of the channel spacers 130).
In accordance with one aspect of the present disclosure, a heat exchanger 100 is formed as a disposable and/or single-use device. As may be appreciated by those of ordinary skill in the art, typical considerations for whether a device, such as a device used in a heat exchanger, and particularly such as in sterilization (or at least viral inactivation) processes, is disposable and/or single-use include, without limitation, cost (so that disposability is economically feasible), weight (e.g., readily portable such as manually portable by a single individual without external assistance, i.e., unassisted manual portability), size (so that the size or thickness or bulk of the device does not unduly impede manipulability by a single individual), and other manufacturing considerations (e.g., use of materials which are easier to work with than others, such as easier to form, shape, cut, etc.). Such considerations affect, without limitation, material selection as well as manner of construction. Additionally, it may not be desirable to sterilize and/or reuse a heat exchanger for biotechnology/biopharmaceutical processes in view of various considerations such as cross-contamination and speed (e.g., of productivity as well as process time generally). Thus, generally, it may be desirable for the heat exchanger 100 used in a biotechnology/biopharmaceutical process to be pre-sterilized, e.g., gamma-irradiated, and readily portable (e.g., by a single individual without external assistance). It may be appreciated that use of a polymeric seal element 134 in the channel spacers 130 to isolate flow paths and/or to contain fluid mediums within desired flow channels 106 may also be more cost effective. Selection of materials and/or configurations of physical barriers 108 may also affect whether the heat exchanger 100 may be considered single-use and/or disposable.
Unlike traditional plate and frame heat exchangers, the physical barrier 108 used in at least one embodiment of a heat exchanger 100 formed in accordance with principles of the present disclosure is significantly thinner than the standard stainless steel plates used in traditional plate and frame heat exchangers. More particularly, the thickness of physical barriers 108 used in a disposable heat exchanger 100 may be selected to be several orders of magnitude thinner than plates used in traditional plate and frame heat exchangers so that it is economically feasible for the heat exchanger 100 to be disposable. In some instances, thin elements such as films or foils, are used that are just thick enough to physically isolate thermal mediums (heating or cooling medium) from the process stream and effectively conduct thermal energy, yet not necessarily thick enough to have structural integrity to maintain a wall configuration independently of another support element (such as the housing 101 or even the channel spacers 130). For instance, the physical barriers 108 may have a maximum thickness of approximately 0.010″ (0.254 mm) and as low as approximately 0.001″ (0.025 mm). It will be appreciated that a very thin physical barrier 108 capable of isolating fluid flows may be formed to be readily manipulated and formed, e.g., easier to cut to the desired shape than a steel plate of a traditional plate and frame heat exchanger. A very thin foil or film may not necessarily be thick enough to maintain its own structural stability (e.g., maintain a planar shape) without external support. The flow element 132 and/or seal element 134 of the channel spacers 130 may impart a degree of structural stability to the physical barrier 108 if the physical barrier 108 is too thin to maintain a fixed or at least semi-rigid configuration (e.g., a planar shape) independently. Although it is recognized that considerations for whether a device is disposable (e.g., economic feasibility) is often a relative consideration, those of ordinary skill in the art of heat exchangers will recognize that a heat exchanger using foils or films as physical barriers 108 would be considered disposable when compared to traditional plate and frame heat exchangers.
The heating and cooling mediums may be supplied directly to the heat exchanger 100. In some embodiments, as shown in
As may be appreciated with reference to
As may be appreciated, the heat exchanger 100 does not heat or cool the heating and cooling mediums on its own. The heating and cooling mediums typically are brought to the desired respective temperatures by separate heating and cooling devices or systems as known in the art, or heretofore developed. In one non-limiting embodiment, the heating medium may be a heated glycol solution heated by a separate heating mechanism. In one non-limiting embodiment which may optionally be used in conjunction with the aforementioned heating embodiment, the cooling medium may be a chilled glycol solution cooled by a separate cooling mechanism. It will be appreciated that other appropriate heating and cooling mediums may be used instead without detracting from principles of the present disclosure and/or use or efficacy of a heat exchanger 100 formed in accordance with one or more principles of the present disclosure.
In the embodiment of
In the example of
Similarly, in the example of
The internal system ports 211p, 211h, 213p, 213h, 221p, 221c, 223p, 223c of the manifold 202 are ported in a manner such that various ports of the manifold 202 mate with corresponding ports of the heat exchanger 100, as may be appreciated with referenced to the example of a manifold 202 embodiment illustrated in
More particularly, a process stream is redirected within the manifold 202 from the manifold process stream inlet port 201 to the manifold heating section process stream feed port 211p which is in fluid communication with the process stream heating section inlet port 111p in the heat exchanger 100. The process stream may then flow through the heating section 110 of the heat exchanger 100 as described above. The heated process stream exiting the heating section 110 of the heat exchanger 100 via the process stream heating section outlet port 113p is then transported back to the manifold 202 via a manifold heating section process stream return port 213p, transported (e.g., laterally) within the manifold 202 in the direction of the cooling section 120 of the heat exchanger 100 and to the manifold cooling section process stream feed port 221p which is in fluid communication with the process stream cooling section inlet port 121p in the heat exchanger 100. The process stream may then flow through the cooling section 120 of the heat exchanger 100 as described above. The cooled process stream exiting the cooling section 120 of the heat exchanger 100 via the process stream cooling section outlet port 123p is then transported back to the manifold 202 via a manifold cooling section process stream return port 223p. The process stream may then be transported within the manifold to the manifold process stream outlet port 203 for collection and/or further processing.
In the example of
Similarly, in the example of
It will be appreciated that the path length and flow rate through the heat exchanger 100 and manifold 202 (if used) contribute to the resonance time and mixing rate and may be varied to achieve the desired process stream target temperature and contact time. The heating and cooling rate may be dictated by the capacity of heating medium flow path and the cooling medium flow path. Both temperature and flow rate affect the amount of heat transferred between a given thermal medium and associated process stream.
The heat exchanger assembly 200 of
It should be appreciated that various embodiments (either individual elements or combinations of elements) illustrated in the figures have several separate and independent features, which each, at least alone, has unique benefits which are desirable for, yet not critical to, the presently disclosed heat exchanger or heat exchanger assembly or method. Therefore, the various separate features described herein need not all be present in order to achieve at least some of the desired characteristics and/or benefits described herein. One or more separate features may be combined, or only one of the various features need be present in a heat exchanger or heat exchanger assembly formed in accordance with various principles of the present disclosure. For instance, it may be desirable simply to heat or cool a process stream without both heating and cooling. It will be appreciated that the disposable/single-use may be independent of the dual-path configuration. Principles of the heat exchanger 100 disclosed herein may be applied for a single-thermal exchange process, e.g., just heating or just cooling.
All apparatuses and methods discussed herein are examples of apparatuses and/or methods implemented in accordance with one or more principles of this disclosure. These examples are not the only way to implement these principles but are merely examples. Thus, references to elements or structures or features in the drawings must be appreciated as references to examples of embodiments of the disclosure, and should not be understood as limiting the disclosure to the specific elements, structures, or features illustrated. Other examples of manners of implementing the disclosed principles will occur to a person of ordinary skill in the art upon reading this disclosure. Although described for use in the context of viral inactivation, the principles of the present disclosure can be applied more broadly if desired. For instance, heat exchanger principles disclosed herein may be applied to continuous heat exchange processes, and/or disposable/single-use heat exchangers, and/or heat exchange processes other than HTST processes.
In the foregoing description and the following claims, the following will be appreciated. The phrases “at least one”, “one or more”, and “and/or”, as used herein, are open-ended expressions that are both conjunctive and disjunctive in operation. The term “a” or “an” or “the” entity, as used herein, refers to one or more of that entity. As such, the terms “a” (or “an”), “one or more” and “at least one” can be used interchangeably herein. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise. All directional references (e.g., proximal, distal, upper, lower, upward, downward, left, right, lateral, longitudinal, front, back, top, bottom, above, below, vertical, horizontal, radial, axial, clockwise, counterclockwise, and/or the like) are only used for identification purposes to aid the reader's understanding of the present disclosure, and/or serve to distinguish regions of the associated elements from one another, and do not limit the associated element, particularly as to the position, orientation, or use of this disclosure. Connection references (e.g., attached, coupled, connected, and joined) are to be construed broadly and may include intermediate members between a collection of elements and relative movement between elements unless otherwise indicated. As such, connection references do not necessarily infer that two elements are directly connected and in fixed relation to each other. Identification references (e.g., primary, secondary, first, second, third, fourth, etc.) are not intended to connote importance or priority, but are used to distinguish one feature from another.
While the foregoing description and drawings represent various embodiments, it will be understood that various additions, modifications, and substitutions may be made therein without departing from the spirit and scope of the present disclosure. In particular, it will be clear to those skilled in the art that principles of the present disclosure may be embodied in other forms, structures, arrangements, proportions, and with other elements, materials, and components, without departing from the spirit or essential characteristics thereof. One skilled in the art will appreciate that the disclosure may be used with many modifications of structure, arrangement, proportions, materials, and components and otherwise, used in the practice of the disclosure, which are particularly adapted to specific environments and operative requirements without departing from the principles of the present disclosure. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of elements may be reversed or otherwise varied, the size or dimensions of the elements may be varied. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, and not limited to the foregoing description.
All of the devices and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the devices and methods of this disclosure have been described in terms of preferred embodiments, it may be apparent to those of skill in the art that variations can be applied to the devices and/or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the disclosure. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the disclosure as defined by the appended claims.
This application claims the benefit of priority under 35 U.S.C. § 119 to U.S. Provisional Application Ser. No. 63/057,020, filed Jul. 27, 2020, the disclosure of which is hereby incorporated herein by reference in its entirety for all purposes.
Number | Date | Country | |
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63057020 | Jul 2020 | US |