System and method for controlling the temperature of a medium by refrigerant vaporization and working gas condensation

Abstract

The present invention provides a system and method for controlling the temperature of a medium. [Solution] A system and method for controlling the temperature of a medium by refrigerant vaporization, working gas condensation, or a combination of both, the system comprising a container, at least one working gas storage tank having at least one storage tank section including at least one storage tank section having an outer surface assembled to provide a volume of heat reachable by the medium in the container and thermally coupled to the volume of the medium in the container, and a condenser for regulating working gas condensation in the storage tank, thereby the working gas storage tank forming a vapor space in each of the at least one storage tank section in response to the receiving of working gas and the regulating of condensation in the condenser, so as to enable working gas condensation at or near a selected temperature of the volume of the medium in the container thermally coupled to each storage tank section.

Description

[Technical Field]

[0001] This disclosure relates to temperature control of a medium, and more particularly to controlling the temperature of a medium by localized temperature control of each localized thermal volume constituting the medium, depending on the properties of the medium. [Background technology]

[0002] Temperature control is a fundamental requirement for successful chemical reaction engineering. Living cells grow and produce products at optimal temperatures, and similarly, chemical catalysis, separation, crystallization, evaporation, filtration, polymerization, isomerization, and other reactions have inherent operating temperatures that best achieve the desired results. [Overview of the project] [Problems that the invention aims to solve]

[0003] Conventional cooling methods lack the ability to accommodate the time- and spatially dependent heat-producing characteristics of chemical and biochemical reactions, particularly those involving low heat output. Such reactions include ethanol and lactic acid fermentation, anaerobic digestion, pharmaceutical cell culture, biodiesel esterification, and industrial polymerization. While these reactions can generate considerable instantaneous heat, the overall heat produced is small, and the heat-producing values ​​often fluctuate significantly over time and space. This variability may also necessitate localized heat addition to maintain a homogeneous temperature profile throughout the reaction.

[0004] For example, red wine fermentation has a heat output that increases sharply in the first few hours, peaks temporarily, and then gradually decreases over the next few days. The fermentation heat output is also directly proportional to the local concentration of metabolically digesting yeast, which can be spatially variable within the tank or vessel. This variation is caused by reliance on CO2 naturally produced for stirring / homogenization, and CO2 production is also directly proportional to the local concentration of metabolically digesting yeast, and further proportional to the overall heat output of the fermentation cycle.

[0005] Failure to control the fermentation temperature of red wine can negatively impact batch quality. Specifically, yeast may aggregate on floating skins, creating localized areas of high heat / accelerated metabolic activity, and die prematurely due to the localized temperature increase. These deaths result in a yeast population insufficient to complete the conversion of all sugars in the tank or container (incomplete / failed fermentation). Furthermore, failure to control the temperature during fermentation can alter the flavor of the wine by changing the yeast's metabolic selectivity for the production of volatile metabolites.

[0006] Conventional temperature control methods for fermentation utilize an external cooling jacket with a variable flow rate of cold water or glycol, and a temperature control element submerged within the reaction vessel. While this method allows for rapid cooling of the vessel volume and quick offsetting of reaction heat, it can lead to unnecessary cooling. For example, the temperature element may correctly recognize the local need for cooling when cooling of the majority of the reaction volume is unnecessary. Similarly, the element may correctly determine that cooling of a nearby reaction volume is unnecessary when the reaction has actually exceeded a set-point temperature elsewhere in the tank or vessel. Similar temperature control challenges are observed when heating of the reaction vessel is desired, using an external heating jacket with a variable flow rate of hot water or steam, and a temperature control element submerged within the reaction vessel.

[0007] One solution to this problem is stirring the reaction volume. Stirring homogenizes the reaction volume, resulting in a more uniform concentration closer to the temperature element and better representing the entire contents of the container. Nevertheless, many common biological reactions, such as ethanol production during beer fermentation, are not artificially stirred because yeast naturally produces CO2, which helps homogenize the fermentation culture. Artificial stirring carries the risk of accidental oxidation of the beer during fermentation, which can alter the flavor profile and shorten the shelf life. Therefore, brewers must rely on natural stirring, but the insufficient homogeneity of the fermentation volume means they cannot be confident that the container cooling or heating system will function optimally.

[0008] Like wine fermentation, beer fermentation is also temperature-sensitive. Generally, beer yeast can be divided into two categories: lager and ale. Lager strains prefer temperatures between 45°F and 55°F, while ale strains prefer fermentation temperatures between 60°F and 70°F. Temperature control is crucial for ensuring quality, especially in terms of flavor and consistency between fermentation batches. Temperatures above or below the desired range, both above and below the desired range, expose the yeast to the risk of both the formation of unwanted chemical byproducts (esters, diacetyls, fusel alcohols, etc.) and heat shock, which can lead to cell damage, including premature death.

[0009] Conventional techniques have been used to design fermenters for cooling tanks or containers using vacuum, water, or air recirculation. For example, U.S. Patent No. 7,685,715 describes a method for handling the contents of a container and tank or vessel, in which a coaxial tank or vessel has an internal cylinder wrapped in a spiral band, the spiral band then covered by an external cylinder, thereby circulating fluid between the cylinders to regulate the temperature of the internal cylinder and its contents.

[0010] U.S. Patent Publication 2005 / 0077029 teaches heat exchange for a fermentation tank or container using an external cylinder having a concentric internal cylinder through which a liquid of a selected temperature passes, in order to regulate the temperature of the contents of the external cylinder. U.S. Patent 7,870,891 teaches the use of a covered fermenter using air as a cooling medium. U.S. Patent Publication 2008 / 0175951 teaches the establishment of a vacuum in a fermenter above the fermented liquid to control the vapor pressure. [Means for solving the problem]

[0011] This disclosure relates, in one embodiment, to a system and method for controlling the temperature of a medium in a container such as a tank or vessel.

[0012] According to one embodiment of the present disclosure, a system and method for controlling the temperature of a medium by working gas condensation are provided. The system includes a container having an exterior and an interior, and at least one working gas storage tank associated with the container, the at least one working gas storage tank having at least one storage tank section configured to hold working gas, each at least one storage tank section having a wall assembled to have an outer surface thermally connected to the volume of the medium in the container and to transmit thermal changes to the volume of the medium in the container, thereby providing a volume of the medium's heat reach within the container, the volume of the medium's heat reach having an outer boundary, and a condenser for adjusting the working gas pressure in the at least one working gas storage tank, wherein the at least one working gas storage tank is configured to form a vapor space in each of the at least one storage tank section in response to receiving working gas and in response to adjustment of the working gas pressure in the condenser, so as to enable working gas condensation at or near a selected temperature of the volume of the medium's heat reach within the volume of the medium in the container thermally connected to each at least one storage tank section.

[0013] According to another aspect of the present disclosure, at least one storage tank section includes a plurality of storage tank sections each having a respective internal storage tank space fluidly connected to at least one other internal storage tank space of an adjacent storage tank section, the plurality of storage tank sections being arranged spaced apart from adjacent storage tank sections each having a respective volume of a continuous media heat reach range with each boundary of the heat reach range.

[0014] According to a further aspect of the present disclosure, the system includes a working gas source fluidly connected to a working gas storage tank and a condensing device, configured to send working gas to the working gas storage tank in response to a change in pressure in the working gas storage tank, as adjusted by the condensing device.

[0015] According to yet another further aspect of the present disclosure, the plurality of storage tank sections are connected together in series, in parallel, or in a combination of series and parallel arrangements.

[0016] According to an additional aspect of the present disclosure, the working gas storage tank comprises a lattice of storage tank sections.

[0017] According to yet another further additional aspect of the present disclosure, R3 is the radius of the volume of the media heat reach range determined as follows.

[0018]

Number

[0019] According to another aspect of the present disclosure, the minimum distance between the centers of adjacent storage tank sections is at least,

[0020]

Number

[0021] According to the present disclosure, a method for controlling the temperature of a medium by condensation of a working gas is provided. This method is to provide an apparatus for controlling the temperature of a medium by condensation of a working gas, a container having an exterior and an interior, at least one working gas associated with the container, wherein at least one working gas storage tank has at least one storage tank section configured to hold the working gas, and each at least one storage tank section has a wall assembled such that an outer surface thereof is thermally connected to a volume of the medium within the container and conveys a thermal change to the volume of the medium within the container, thereby providing a volume of a medium heat reach range within the container, the volume of the medium heat reach range having an outer boundary, and at least one working gas, a condensation device for adjusting the working gas pressure in at least one working gas storage tank, At least one working gas storage tank, configured to form a vapor space in each of at least one storage tank sections in response to receiving working gas and in response to adjustment of the working gas pressure condenser, so as to enable working gas condensation at or near a selected temperature for the volume of the medium within the heat reach range of the medium in a container thermally connected to each at least one storage tank section, This includes providing Introducing working gas into at least one working gas storage tank so as to partially occupy at least one storage tank section in at least one storage tank section, Adjusting the working gas pressure in at least one storage tank section to allow working gas condensation at or near a selected temperature for the volume of the medium within the heat reach range relative to the volume of the medium in a container thermally connected to at least one storage tank section, Includes.

[0022] According to another embodiment of the method described above, the following steps are included: The process of partitioning the medium into localized heat volumes, Thermally connecting a working gas to each localized heat volume in order to control the temperature of the localized heat volume and maintain the medium at a selected temperature.

[0023] According to further aspects of the present disclosure, partitioning a medium into localized thermal volumes includes locating working gas storage tanks in physical proximity to the container, with at least one working gas storage tank section associated with each localized thermal volume.

[0024] According to yet another aspect of the present disclosure, thermal coupling includes adjusting the working gas pressure in each of the at least one storage tank sections to maintain the temperature of each localized heat volume at a selected temperature of the medium.

[0025] As readily apparent from the foregoing, this disclosure provides a system and method for controlling the temperature of a medium by performing localized temperature control of the medium. While a typical embodiment of this disclosure is described in the context of fermentation, the system and method of this disclosure has applications for both heating and cooling of a wide variety of mediums to maintain their temperatures, and represents a novel approach to engineered temperature control that adjusts to both temporal and spatial differences in the amount of heat required, without requiring advanced control and programming. In contrast to conventional methods that heat the entire system volume at maximum intensity except by varying the length of time, the novel approach of this disclosure adjusts the temperature only in spatial areas where heating is required, for example, and where the intensity is directly proportional to local heat loss. Thus, cooling of the medium is not achieved directly, but rather through careful adjustment of the net amount of heat required for the reaction. The working gas pressure can be adjusted to change the setpoint temperature of the medium, and this disclosure ensures that the acceptable local change in temperature never falls below this new setpoint. Thus, it is possible to influence the slow, intentional cooling of the medium.

[0026] Conventional systems use hot water or steam that is activated whenever the measured setpoint temperature is exceeded. Activation is controlled by a local temperature near the sensing element, and heating is achieved rapidly through the use of a large temperature gradient between the hot water or steam and the system volume. Once the higher temperature setpoint is reached, the heating system is deactivated.

[0027] This approach has two obvious drawbacks: (1) the entire system volume is heated based on a local subset of the state, and (2) the entire system volume is susceptible to large temperature gradients during the heating cycle. Consequently, system contents located some distance from the sensing element are heated whether necessary or not, and the system contents are susceptible to thermal shock. This thermal shock can be more pronounced in contents near the external heating jacket or internal heating coil, especially when the system volume lacks consistent agitation or homogenization.

[0028] This disclosure avoids these drawbacks by using a working gas located in a shallow horizontal tube and connected in a common space. The working gas is held at or near a desired temperature in the system volume, and its condensation is controlled so that the working gas condenses at this same temperature. The condensed liquid in the horizontal tube is quickly removed, and since the vapor space of the tube remains connected, each horizontal section subsequently condenses at approximately the same pressure / temperature as the horizontal sections above and below it.

[0029] Temperature control of the system volume is influenced by the control of condensation of the working gas. When the working gas is at its condensation point, it changes phase to a liquid and releases a large amount of energy per unit volume, but it also releases this energy at a constant temperature. Therefore, any local system volume near horizontal tubes is protected from falling below the condensation temperature of the working gas within the tubes, as long as these tubes contain the working gas.

[0030] This disclosure provides passive, continuous, and ongoing protection from a drop in the setpoint temperature of the system volume. The temperature sensing element no longer needs to activate the heating system because local working gas condensation adds heat as soon as heat is needed and near the spatial point of requirement. Furthermore, a high temperature gradient for heating is no longer required because heat transfer must no longer occur rapidly and over long distances (e.g., from the container wall to the center of the container). As the local heat requirement fluctuates, the local temperature difference between the system volume and the working gas coil also fluctuates, and heat is added proportionally by the local standby mass of the working gas.

[0031] In summary, the systems and methods of this disclosure significantly improve upon conventional temperature control methods. This approach is no longer subject to the risk of overheating the entire system volume based on conditions near a local temperature sensing element, or failing to activate the heating system when needed based on local conditions near the sensing element. This disclosure also eliminates the need to create large temperature gradients that could risk thermal shock of the system contents. Furthermore, controlled media cooling can influence the use of the endothermic heat required for the reaction itself, without the risk of overheating and the possibility of thermal shock of the system contents. The benefits of improved temperature control include optimized reaction rates, reduced undesirable side reactions, and improved inter-batch consistency for batch processes.

[0032] The aforementioned and other features and advantages of this disclosure will be more readily apparent when used in conjunction with the accompanying drawings, so as will be better understood from the following detailed description. [Brief explanation of the drawing]

[0033] [Figure 1] A diagram of radial heat transfer along the length of a horizontal grid section according to this disclosure. [Figure 2] Cross-sectional view of radial heat transfer along the length of the horizontal grid section in Figure 1. [Figure 3] A diagram illustrating the derivation of the ideal spacing between grid tubes calculated via a right-angle shape, according to this disclosure. [Figure 4] Cross-sectional views of multiple cooling volumes having the minimum reach, according to this disclosure. [Figure 5] Cross-sectional views of multiple cooling volumes having partial reach, according to the present disclosure. [Figure 6] Cross-sectional views of multiple cooling volumes having complete reach, according to the present disclosure. [Figure 7] A diagram of a system formed according to a representative embodiment of the present disclosure. [Figure 8] A side cross-sectional view of a refrigerant storage tank formed in accordance with this disclosure and located inside a container. [Figure 9] Figure 8 is a plan view of the refrigerant storage tank. [Figure 10] A diagram of a refrigerant storage tank outside a container, according to another embodiment of the present disclosure. [Figure 11] A diagram of a system formed according to a typical embodiment of the present disclosure, in which zone-level pressure control is influenced by multiple pressure regulators. [Figure 12] A side cross-sectional view of a refrigerant storage tank formed according to an alternative embodiment of the apparatus in Figure 8. [Figure 13] A schematic description of an alternative embodiment of the present disclosure in which the coil device is located outside the container. [Figure 14] Cross-sectional view of radial heat transfer along the length of the horizontal grid section. [Figure 15] A diagram illustrating a design for a vibrating vacuum coil and storage tank in which a fluid inside the coil vibrates due to a pressure difference, according to another embodiment of the present disclosure. [Figure 16] A diagram of a system formed according to a typical embodiment of the present disclosure, in which the refrigerant is preheated before refilling the refrigerant storage tank. [Figure 17] A diagram of a system formed according to this disclosure, in which a heat transfer medium is circulated through a storage tank and the flow rate varies based on the measured temperature. [Figure 18] A diagram of radial heat transfer along the length of a horizontal grid section according to this disclosure. [Figure 19] Cross-sectional view of radial heat transfer along the length of the horizontal grid section in Figure 18. [Figure 20] Cross-sectional views of multiple heating volumes having the minimum reach, according to this disclosure. [Figure 21] Cross-sectional views of multiple heating volumes having partial reach, according to the present disclosure. [Figure 22] Cross-sectional views of multiple heating volumes having complete reach, according to the present disclosure. [Figure 23] A diagram of a system formed according to a representative embodiment of the present disclosure. [Figure 24] A diagram of the system formed according to an alternative embodiment of the system in Figure 23. [Figure 25]A side view of a cross-section of an operating gas storage tank, formed in accordance with this disclosure and positioned inside a container. [Figure 26] Figure 25 is a plan view of the working gas storage tank. [Figure 27] A diagram of an external working gas storage tank according to another embodiment of the present disclosure. [Figure 28] A side cross-sectional view of a refrigerant storage tank formed according to an alternative embodiment of the apparatus shown in Figure 25. [Figure 29] Cross-sectional view of radial heat transfer along the radius of a horizontal grid section. [Figure 30] Cross-sectional view of the radial temperature profile of an adjacent refrigerant storage tank. [Figure 31] Cross-sectional view of the temperature profile of the adjacent working gas storage tank. [Figure 32] Cross-sectional view of the temperature profile for a combination of adjacent refrigerant storage tanks and working gas storage tanks. [Modes for carrying out the invention]

[0034] In the following description, certain specific details are given in order to fully understand the various embodiments of the disclosure. Nevertheless, those skilled in the art will recognize that the embodiments can be practiced without one or more of these specific details, or with other methods, components, materials, etc. In other examples, well-known structures associated with tanks or containers, refrigerants, working gases, vaporization and vacuum systems, condensing systems, tubing, pipes, and coils are neither shown nor described in detail so as not to obscure the description of the embodiments unnecessarily. References to “medium” are intended to include gases, liquids, solids, and gels and other states. References to “container” are intended to include tanks and containers, without limitation. Furthermore, references to “pipe” or “tube” are intended to include conduits of various cross-sectional geometric configurations and conduits of any length, unless otherwise specified herein.

[0035] Unless otherwise required by context, throughout this specification and the subsequent claims, the word “comprise,” and its variations such as “comprises” and “comprising,” shall be interpreted in a broad, inclusive sense, including, but not limited to.

[0036] Any reference throughout this specification to "one implementation" or "an implementation" means that any particular feature, structure, or characteristic described in relation to an embodiment is included in at least one embodiment. Therefore, the occurrence of the phrase "in one implementation" or "in an implementation" in various places throughout this specification does not necessarily refer to all instances of the same embodiment. Furthermore, any particular feature, structure, or characteristic may be combined in any suitable manner in one or more embodiments. For the sake of brevity and clarity of the illustration, it will be understood that reference numbers may be repeated in the figures to indicate corresponding or similar elements or steps, where appropriate.

[0037] As used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural nouns unless otherwise explicitly indicated. It should also be noted that the term “or” is generally used in its broadest sense to mean “and / or” unless otherwise explicitly indicated.

[0038] The title and abstract of this disclosure provided herein are for convenience only and do not constitute an interpretation of the scope or meaning of the embodiments.

[0039] In contrast to conventional temperature control methods, this disclosure provides both process heating and process cooling of a medium using a minimum temperature gradient. While a gradient must be generated for successful heat transfer according to this disclosure, this gradient does not need to be large, given the low heat transfer requirements of many common processes (e.g., cell culture) and the ability to remove heat while continuously generating or applying it. Furthermore, a large temperature gradient between the temperature control source and the target volume (i.e., the medium) can actually damage the medium via thermal shock near the heating or cooling system interface. This can occur, for example, near the inner wall of a covered cell culture reactor.

[0040] In general, some of the mechanical structures in the embodiments of this disclosure resemble metal grids. In one aspect of this disclosure, the structure is immersed in a volume requiring temperature control. Alternatively, the grid can be located outside a container holding the medium. Ideally, the grid shape, construction material, and cooling system components are determined according to the medium to be cooled. Nevertheless, the cooling performance of a structure formed according to this disclosure with a given grid shape, construction material, and working gas cooling system can be determined for any medium.

[0041] While typical embodiments of this disclosure will be discussed in the context of cooling a medium, such as in the processes of beer and wine fermentation, it will be understood that the systems and methods of this disclosure should have applications not only in cooling various mediums but also in other processes and heating.

[0042] The grid designs described herein have three main aspects: (1) internal grid dimensions, (2) structural materials for the grid, and (3) spacing between adjacent grid components. All grid designs have a common upper space and horizontally isolated sections that hold a large amount of liquid refrigerant. These features ensure that the refrigerant in each horizontal section evaporates at the same temperature and that there is always enough liquid refrigerant to dissipate the heat generated nearby. Maintaining the height of the liquid refrigerant in each horizontal section is often determined by the orientation of this section relative to gravity.

[0043] Logically, a grid can consist of a series of horizontal sections of any shape and size, as long as the series of horizontal sections can contain the liquid refrigerant. In practice, it is most cost-effective to use cylindrical pipes or tubes defined for the perfect vacuum required for many refrigerants, rather than relying on the advanced fabrication techniques required for specially shaped containers for perfect vacuum. Ideally, these pipes should be filled to 70% to provide sufficient surface area for vaporization of the liquid refrigerant from the internal surface of the upper space, while still retaining the maximum volume of liquid refrigerant inside the pipes / tubes. Furthermore, the empty upper space allows the evaporated vapor to move unobstructed along the length of the horizontal sections to the vacuum source. The choices for the internal design of the grid are application-specific, but particularly in relation to the choice of refrigerant and the cooling method (vacuum pump, compressor, etc.).

[0044] Logically, the lattice construction material is limited by the requirement that the material does not mechanically affect the medium to be cooled and does not affect the operating state of the refrigerant trapped within. In practice, the construction material is often determined by cleaning requirements (e.g., hygiene requirements for cell culture) and the thickness of commercially available materials. The choice of lattice construction material is application-specific, but the thickness of the material can be adjusted to improve heat transfer, for example, regardless of increased cost.

[0045] Logically, the spacing between adjacent grid sections is determined by the medium to be cooled and its desired temperature profile, and is independent of the horizontal length. For example, the flavor profile of a particular wine can be best produced within a 5°F range, from 70°F to 75°F; therefore, the spacing is configured such that the outer grid surface is maintained at 70°F, and a maximum of 75°F occurs at the centerline between adjacent sections. In practice, the spacing between grid sections is often determined by the desired construction material, welding costs, container shape, ease of removal for maintenance, ease of cleaning, etc. Nevertheless, the ideal spacing can be determined by applying the radial heat transfer equation to the horizontal coil sections, ignoring the length of the horizontal coil sections (see drawings and derivatives). Instead, the horizontal length is almost always determined by the need to provide the desired grid spacing through the medium to be cooled and the need to ensure the presence of a sufficient liquid volume of the coolant in each horizontal section.

[0046] The ideal grid spacing can be determined by a set of user-defined variables, making the use of a mathematical approach preferable. A further advantage is that the complete grid structure can be designed by examining the spacing requirements of the cross-section of a single horizontal grid element.

[0047] For example, if sanitary requirements necessitate specific building materials and the selection of a cooling system requires a particular refrigerant, both of these measures can be incorporated into the interval equation. Similarly, for existing grid structures and cooling systems, the expected temperature gradient inside the medium to be cooled can be calculated for any medium type.

[0048] An important user-defined temperature variable is the maximum allowable temperature difference inside the medium to be cooled. For example, if a maximum temperature gradient of 5°F and a maximum temperature of 75°F are desired, the ideal grid spacing can be calculated using the derived equation, which is described in more detail below, assuming a refrigerant vaporization temperature of 70°F inside the grid pipe and a centerline temperature of 75°F for the medium between adjacent grids.

[0049] Nevertheless, the explained value of 5°F is actually greater than the minimum temperature gradient required for successful heat transfer. In reality, this value represents the total transfer force required to move heat from the furthest limits of the medium to the point of refrigerant vaporization, and is greater than the value required to move heat only to the outer surface of the grid.

[0050] This larger value actually has three components: (1) the temperature difference for transferring heat through the medium being cooled from the center line between the grid cells and to the surface of the grid; (2) the temperature difference for transferring heat through the mechanical structure of the grid from the outer surface of the grid and to its inner surface; and (3) the temperature difference for transferring heat through the liquid refrigerant from the inner surface of the grid and to the liquid-vapor refrigerant interface where evaporation occurs.

[0051] More specifically, the maximum allowable temperature gradient for heat transfer through the target medium is determined by the end user. This value varies based on the desired properties of the medium over the cooling timescale (e.g., flavor profile). For different mediums and fixed grid spacings, a larger gradient value results in greater resistance of the medium to heat flow. Nevertheless, increasing the surface area effective for heat transfer from the medium to the grid can reduce this gradient. For example, additional surface area can be created through the use of fin-type structures attached to the outer surface of the grid.

[0052] The temperature gradient across the entire wall of the lattice's mechanical structure is determined by the lattice construction material and its thickness. For a common lattice shape and structure, this gradient value is constant regardless of the medium being cooled.

[0053] The temperature gradient from the inner wall of the grid to the liquid-vapor refrigerant interface is determined by the selected refrigerant and the distance from the inner wall to the interface. For known refrigerants and the height of the liquid refrigerant inside the tube, this gradient value is constant regardless of the medium being cooled. Furthermore, the upper space of a partially filled liquid refrigerant tube can form a thin liquid film of evaporated refrigerant on its inner surface, reducing the distance required for heat to travel from a certain percentage of the inner surface to the liquid-vapor interface. Intentionally roughening the inner surface can also improve vaporization heat transfer and effectively reduce the temperature gradient required to transfer an equivalent amount of heat from the inner wall to the liquid-vapor refrigerant interface.

[0054] Given a grid shape, construction materials, and cooling system, horizontal sections are responsible for cooling the same volume of medium. Nevertheless, the heat generated by this volume can vary depending on the properties of the medium, and therefore, the observed cooling performance of the grid can also vary.

[0055] Referring to Figures 1 and 2, for a given horizontal grid section 50, the mechanical design must be able to remove the maximum heat generated by the medium volume 52 surrounding this horizontal grid section 50, which has an outer boundary 53. This volume can be approximated by assuming a cylindrical shape surrounding the horizontal grid section 50 with radius R3, which is the combination of the distance R2 from the centerline of the grid to the outside of the tube and the distance from the outside of the grid to the centerline between adjacent grids. The volume of the mechanical grid is then subtracted from the total volume of the medium-filled container in order to calculate the volume of the heat-producing medium.

[0056] R1 is the inner radius of the grid tube 54 and should be selected according to the desired cooling system. In a batch filling system, each horizontal grid tube 54 must hold a sufficient mass of refrigerant to absorb the maximum heat generated by the surrounding medium during a given time between fillings (e.g., 1 hour). In a constant refill cooling system, this volume can be much smaller, but it is still affected by the measure that a sufficient volume of refrigerant remains for vaporization over the entire horizontal length during the maximum medium heat production.

[0057] The horizontal length L of the horizontal grid section 50 becomes a key variable for establishing the refrigerant holding volume, primarily determined by the value of R1, which is determined by the choice of cooling system. In practice, the chosen length L per horizontal grid section 50 almost always exceeds the required minimum, as this value is primarily chosen for structural support and to ensure that the minimum spacing requirement is met throughout the medium.

[0058] The grid shape (spacing) varies based on several variables, including the medium, refrigerant, cooling method, and construction materials. The ideal spacing between the centerlines of adjacent grids for wine production should be roughly 6 inches, for example, with a grid of 1" OD sanitary stainless steel tubing, using ethanol refrigerant under vacuum, and with an acceptable temperature variation of 5°F. An acceptable temperature variation of 10°F should increase this ideal spacing to approximately 9 inches, and a change in OD tubing from 1" to 2" with the same 10°F difference should further increase the ideal spacing to roughly 12 inches.

[0059] Furthermore, design considerations must be given to the pressure drop in the space above the grid 56 during system operation. For example, in a batch filling system using a vacuum pump, the pressure at the interface 58 between the liquid 60 and the vapor refrigerant 62 should always be greater than the pressure of the vacuum source. Minimizing this pressure drop is an important measure of grid design because the pressure drop reduces the vacuum level that must be maintained by the vacuum source.

[0060] For illustrative purposes, a maximum liquid ethanol vaporization rate of 2 L / hr can be expected for 700 L of fermenting wine. This vaporization of liquid mass corresponds to approximately 5 CFM of vapor production at a set temperature of 80°F. With a permissible pressure drop of only 5% due to the system geometry, this piping can be used to connect the upper space to a vacuum source, provided that the equivalent length (straight length and size) of the 0.75” ID piping does not exceed approximately 115 ft.

[0061] Furthermore, the grid design and mathematical methods can be adapted for use outside the container, instead of a cooling jacket. This may be particularly beneficial for containers with small diameters, as the grid should not be in contact with the final product and therefore do not require washing between batches. However, this design may only be practical if the spacing between adjacent grids is calculated to be close to the container diameter.

[0062] An example of a mathematical derivation for determining the ideal coil spacing is provided below.

[0063]

number

number

number

[0064] This equation can be solved for the value R3, taking into account user-defined values ​​for all other variables. User-defined values ​​can be derived from published literature, previous design experience, variations in the acceptable temperature of the medium, and the size and thickness of commercially available pipes / tubes. Note that this mathematical analysis is independent of the length of the horizontal section.

[0065] Using a known value for R3, the ideal spacing between the pipes is calculated via the right-angle shape. The derivation of this equation is shown in Figure 3.

[0066] In this example, note that the variable R3 is equal to the sum of a + b + c, where "a" is the outer radius of the grid pipe, "b" is the distance between the grid pipe and the small cluster of yeast cells, and "c" is the radius of the small cluster of yeast cells. The total spacing between the grid pipe centerlines is:

[0067]

number

[0068] As shown in Figures 4 to 6, alternative geometric configurations can increase the spacing between grid sections, but some parts of the medium may then exceed the design temperature range due to insufficient cooling. Figure 4 is a cross-sectional view of multiple cooling volumes with minimum reach, Figure 5 is a cross-sectional view of multiple cooling volumes with partial reach, and Figure 6 is a cross-sectional view of multiple cooling volumes with full reach.

[0069] Figure 7 shows a system 70 for controlling the temperature of a medium 72 by refrigerant vaporization. In this representative embodiment, the system includes a container 74 having an exterior 76 and an interior 77. At least one refrigerant storage tank 78 is associated with the container 74, and the refrigerant storage tank 78 includes at least one storage tank section 80 assembled to hold the refrigerant 82 in an internal storage tank space 83. In this embodiment, as clearly shown in Figures 8 and 9, there are multiple storage tank sections 80, each storage tank section 80 having a wall 84 with an exterior surface 86 assembled to be thermally connected to the volume of the medium in the container 74 and to introduce a thermal change to the volume of the medium in the container 74, thereby providing a volume of the heat reachable range 52 of the medium in the container, as described above with Figures 1 to 6 and more fully described below.

[0070] Each of the storage tank sections 80 has its own internal storage tank space 83, which is fluidly connected to at least one other internal storage tank space 83 of an adjacent storage tank section 80, and the multiple storage tank sections 80 are spaced apart from adjacent storage tank sections 80, with each volume of the medium heat reachable range 52 having at least the respective boundaries of a continuous heat reachable range.

[0071] The system 70 further includes a vapor pressure device 88 for adjusting the refrigerant vapor pressure in the storage tank sections 80. Each storage tank section 80 is configured to form a vapor space 90 in each storage tank section 80 in response to receiving a refrigerant 82 to allow refrigerant vaporization at or near a selected temperature for the volume of the medium 72 in the container 74 thermally connected to each storage tank section 80, and in response to adjustments of the vapor pressure device 88 over the refrigerant 82 vapor pressure.

[0072] The vapor pressure apparatus 88 can be implemented using readily available commercial equipment and will therefore not be described in detail herein. Briefly, the vapor pressure apparatus 88 includes a vacuum pump 92 fluidly coupled to a refrigerant storage tank 78. Ideally, a pressure regulator 94 is positioned between the vacuum pump 92 and the refrigerant storage tank 78. Control of the vacuum pump 92 can be performed manually or, more preferably, by automated control utilizing sensors and a computer processor to process signals from the sensors and transmit control signals to the vacuum pump in response to the sensor signals.

[0073] In the embodiment shown in Figure 7, a condenser 96 is provided for condensing a refrigerant such as ethanol. The condenser 96 is fluidly connected to the refrigerant storage tank 78 to provide a continuous or uninterrupted supply of the refrigerant to the refrigerant storage tank 78. A chilled water tank 98 is connected to the condenser 96 via a water supply pump 100 for fluid water connection.

[0074] The refrigerant source, such as the refrigerant tank 102, is fluidly connected to the refrigerant storage tank 78 and the vapor pressure device 88, and is configured to supply refrigerant 82 to the refrigerant storage tank 78 in response to changes in the vapor pressure of the refrigerant storage tank 78, as regulated by the vapor pressure device 88. The condenser 96 is also fluidly connected to the refrigerant tank 102 via the vent solenoid 104. The refrigerant tank 102 is then connected to the refrigerant storage tank 78 via the refrigerant pump 106 and in parallel with the drain solenoid 108 to supply refrigerant to the refrigerant storage tank 78. The isolation solenoid 110 is positioned between the refrigerant storage tank 78 and the parallel connection of the refrigerant pump 106 and the drain solenoid 108. Element LT is a level transmitter that detects and transmits an indication of the volume of refrigerant in the refrigerant tank 102. Element PT is a pressure transmitter that detects and communicates an indication of the refrigerant vapor pressure in the vapor space.

[0075] In the embodiment shown in Figure 7, the refrigerant storage tank 78 is automatically refilled at regular intervals via the refrigerant pump 106 to replenish evaporated refrigerant 82 and control the temperature of the medium 72. A vent solenoid 104 draws refrigerant from the condenser 106 to the refrigerant tank 102. The vent solenoid 104 also provides a closed-loop path from the refrigerant pump 106 to the refrigerant tank 102, ensuring that the internal storage tank space 83 is completely filled with refrigerant 82. A drain solenoid 108 functions to remove excess refrigerant 82 from the refrigerant storage tank 78 to the refrigerant tank 102 via gravity, creating a vapor space 90.

[0076] As shown in Figure 8, in one embodiment, the refrigerant storage tank 78 has a manifold 112 connected to each of the storage tank sections 80 for fluid connection to the ventilation line 114 and to the combined filling, draining, and vacuum line 116, the manifold 112 enabling system refrigerant filling and draining, and system connection to the vacuum pump 92. Multiple storage tank sections 80 can be connected together in series, in parallel, or in a combination of series and parallel arrangements. In one embodiment, the refrigerant storage tank 78 comprises a grid of storage tank sections 80. Each storage tank section 80 is held in place by vertical supports 93, as with the manifold 112. Each storage tank section 80 includes at least one weir 117, which is made and shaped to divide the storage tank section into a vapor space 90 and a space for the refrigerant 82. In this embodiment, the weir 117 is a curved section of a pipe or coil that forms the storage tank section 80, and the weir 117 includes a first wall 119, the first wall 119 contacting a second wall 121 at an upward angle, and the second wall 121 forming a vertex 123 at a downward angle. The vertex 123 acts as a dam for the refrigerant 82, and the height of the vertex 123 in the storage tank section 80 determines how much refrigerant 82 is held in this storage tank section 80.

[0077] According to another aspect of this disclosure, the refrigerant storage tank 78 may be located outside the container 74, as shown in Figure 10.

[0078] During operation, the refrigerant 82 is introduced into the refrigerant storage tank 78 and partially occupies the storage tank section 80, forming a vapor space 90 above the refrigerant 82 in the internal storage tank space 83 of each storage tank section 80. The vapor pressure above the refrigerant 82 in the refrigerant storage tank 78 is adjusted to allow refrigerant vaporization at or near a selected temperature of the volume of the medium heat reach range 52 relative to the volume of the medium 72 in the container 74 thermally connected to each storage tank section.

[0079] The system operation requires that the refrigerant vaporizes uniformly, or preferably at the same temperature, throughout the coil. Furthermore, the volume of liquid refrigerant must be maintained sufficiently throughout the coil to remove the heat generated by the medium through vaporization. Proper orientation of the coil relative to gravity ensures that the large volume of liquid refrigerant within the coil conforms to the design intent of the coil's weir and dam. The coil metallurgy must be selected so as not to adversely affect the quality of the medium to be cooled, and the coil should be cleaned between uses to avoid possible contamination of the new medium to be cooled. The refrigerant vapor pressure should provide refrigerant vaporization at or as close as possible to the desired temperature of the medium to be cooled, to avoid possible thermal shock to the medium.

[0080] In batch-type systems using a vacuum pump, the coils must be properly positioned in the correct orientation relative to gravity, filled with liquid refrigerant, drained to create a common upper space connecting the horizontal sections, and isolated to create a common vapor pressure space above all the remaining liquid refrigerant inside. The vacuum pump is activated, and the vacuum regulator allows for adjustment of the refrigerant vapor pressure to match the desired heat removal profile of a given medium. The time between liquid refrigerant refills should be kept to a maximum, as the coils will be unable to cool during the refill sequence. Nevertheless, the time between refills must also be frequent enough to ensure that sufficient liquid refrigerant remains present in all sections of the coils to provide the desired volume of the medium's heat reach. The choice of refrigerant vapor pressure and the time between refills are determined by the heat production profile of the medium to be cooled over time. Ideally, during refills, the temperature of the fresh liquid refrigerant should be at or near the desired setpoint temperature of the medium to be cooled to avoid thermal shock to the medium.

[0081] In conventional continuous systems using refrigerant compressors, the proper orientation of the coil relative to gravity ensures optimal system performance by maintaining the refrigerant liquid volume as designed in each horizontal section. A common vapor upper space is similarly maintained as designed. Compressor performance must also be monitored for the heat production profile of the medium over time. Most importantly, the compressor must be able to operate continuously with variable vapor refrigerant flow rates and across the entire desired range of refrigerant vapor pressure. Cell culture, for example, can vary its heat production rate depending on both time and batch size. System monitoring must be robust enough to adjust system operation to unexpected fluctuations in process variables without risking damage to the compressor and associated components.

[0082] The choice of refrigerant depends on the heat production profile of the medium to be cooled and the optimal production temperature for the selected cooling equipment. For example, in a batch system using a vacuum pump and ethanol refrigerant, the pressure drop between the vacuum source and the coil during system operation makes it difficult to maintain an operating pressure below 0.15 psia (pounds / square inch absolute pressure). Nevertheless, 0.15 psia corresponds to an ethanol refrigerant vaporization temperature of approximately 40°F, and therefore, the combination of a vacuum pump and ethanol refrigerant is best suited for applications where the medium to be cooled must be maintained above 40°F. After installation, the pressure drop between the vacuum source and the coil must be recalculated according to the system geometry to ensure that the selected refrigerant vaporizes at the desired temperature, enabling successful system operation. Operationally, the refrigerant vapor pressure corresponds to the refrigerant vaporization temperature. The objective is to control the refrigerant vapor pressure in the coil at or near the vapor pressure of the setpoint temperature of the medium to be cooled, and at its specific vaporization temperature.

[0083] Regarding wine fermentation, the common maximum permissible temperature range is 64–77°F for red wine and 50–59°F for white wine. Assuming an ethanol refrigerant and vacuum pump combination, these temperature ranges correspond to vapor pressures of approximately 0.232–0.288 psia for red wine and 0.184–0.213 psia for white wine. Assuming an R-134a refrigerant and compressor combination, these temperature ranges correspond to vapor pressures of approximately 77.10–96.11 psia for red wine and 59.98–70.61 psia for white wine.

[0084] Regarding beer fermentation, the common maximum permissible temperature range is 60–70°F for ales and 45–55°F for lagers. Assuming an ethanol refrigerant and vacuum pump combination, these temperature ranges correspond to vapor pressures of approximately 0.217–0.256 psia for ales and 0.169–0.200 psia for lagers. Assuming an R-134a refrigerant and compressor combination, these temperature ranges correspond to vapor pressures of approximately 71.87–85.48 psia for ales and 54.62–65.72 psia for lagers.

[0085] The system must also be cooled throughout the fermentation cycle. For primary fermentation of both red and white wine, 3 to 5 days is generally required. For primary fermentation of beer, 1 to 2 weeks is generally required for ale, and 1 to 2 months is generally required for lager.

[0086] This disclosure will be understood to be applicable to various systems, apparatus, and devices for several uses, including, but not limited to, the following: 1. Artificial generation of convective flow to enhance thermal siphon agitation / homogenization of a medium via a vaporized refrigerant held at different pressures. 2. Use of vaporized refrigerant to indicate the spatial location of heat transfer. 3. Use of buffer cooling fluid to improve the consistency of heat transfer. Here, the buffer fluid is in thermal contact with both the refrigerant storage tank and the medium. 4. Generation of internal flow of vaporized refrigerant to improve heat transfer through fluctuations in vapor pressure. 5. Preheating of the refrigerant before supplying it to the vaporizer, for heating of the medium such that both heating and evaporative cooling can be affected by the same refrigerant vaporizer. 6. Use of a non-condensing or non-vaporizing heat transfer medium to approximate the function of a condensing working gas or vaporizing refrigerant by monitoring changes in the heat transfer fluid temperature between supply from and return to the device at intervals. 7. Use of a condensing working gas to create a localized heat volume for heating the medium. Here, the coil spacing is governed by the same principles and equations as those for vaporized refrigerants. 8. Use of an intermediate medium such as plastic, metal, gel, or coating on the outside of the surface of the working gas storage tank or refrigerant storage tank, where the intermediate medium is in contact with both the surface of the working gas storage tank or refrigerant storage tank and the medium. 9. A combination of a working gas storage tank and a refrigerant storage tank for simultaneous heating and cooling of the medium. 10. Utilization of a working gas condenser and a refrigerant vaporizer inside a stirring tank.

[0087] Each of these embodiments is described in more detail below, along with the accompanying diagrams.

[0088] 1. Artificial generation of convective flow to enhance thermal siphon agitation / homogenization of a medium via a condensing working gas or vaporized refrigerant held at different pressures. As shown in Figure 11, a system 120 is shown having multiple vertically arranged coil sections 122 within a container 124. Control of different vertical coil sections 122 at different vacuum pressures is achieved by using a regulator 126 and a pressure sensor (not shown), which may be manually or automatically connected to a vacuum pump 128. These can be used to alter the flow of current inside the medium in the container 124, such as beer, to improve heat transfer from the beer to the coil surface. They can also be used to control the agitation of the beer through a thermal siphon effect.

[0089] The electronic controller 130 is connected to the sensor, pressure regulator 126, and vacuum pump 128. The construction of the electronic controller 130 is within the capabilities of those skilled in the art and will not be described in detail herein. Briefly, an on-site wired controller or a remote wireless controller, such as an app on a mobile computing or mobile communication device, such as a cell phone, tablet, and the like, is provided to communicate with the components to monitor their status and send control signals to the components. Controlled agitation is important for fermentation, transfer, and storage, and the pressure may be fixed or circulating, and automated control and maintenance of the upper space pressure of the cooling medium is adjustable. A single pressure control setpoint is possible for the entire upper space of the storage tank via electronic communication with a pressure transmitter that measures the upper space pressure and a vacuum source. The upper space of the storage tank may also be divided into sections so that individual parts of the cooling medium storage tank can be controlled in different zones of different pressures.

[0090] In one embodiment, hot siphon stirring can be used for homogenization during fermentation and to maintain this homogenization during the lager maturation phase (during and after the cold crush to around 32°F). Hot siphon stirring can be optimized to control the strong wort movement during fermentation and improve the contact efficiency between the yeast and the wort.

[0091] The heat exchanger's storage tank is fluidly connected to a cooling medium supply and a vacuum source so that the cooling medium fills the storage tank, leaving a selected amount of upper space. The storage tank is also fluidly connected to a vacuum source to provide controlled vacuum vaporization at or near the temperature of the medium (e.g., beer) by drawing a desired level of vacuum from the upper space of the storage tank. Assuming an ethanol refrigerant, the vacuum level should be between 0.169 psi and 0.200 psi for lagers, corresponding to fermentation temperatures of 45°F to 55°F, and between 0.248 psi and 0.265 psi for ales, corresponding to fermentation temperatures of 68°F to 72°F. Furthermore, an indication of the upper space pressure can be provided so that the vaporization of the cooling medium is detected and displayed, indicating the thermal activity inside the medium.

[0092] In a further aspect of the present disclosure, a cooling coil for the bottom of the interior of the fermentation tank is utilized, replacing a second cooling jacket used for maturing the lager. This cooling coil improves homogenization by preventing separation of the beer by gravity, density, temperature difference, or any combination thereof, when the yeast is mainly dormant or does not produce the CO2 necessary for natural agitation. The coil may also be used for heating the bottom of the interior of the fermentation tank, when a vaporized refrigerant is replaced by a condensing working gas instead.

[0093] The coil temperature setpoint can change during the fermentation cycle, including the cold crush of the beer, and is often different from the desired temperature of the fermentation tank or the temperature setpoint of the higher cooling jacket. This difference creates a thermal gradient inside the tank, the magnitude of which is determined by the desired radius and temperature difference of the localized heat volume surrounding the heating or cooling coil. These gradients, in turn, help to create movement of the medium through the utilization of the density difference of the beer depending on its local temperature; as a general principle, in the presence of gravity, a lower-density, warmer fluid rises and a higher-density, colder fluid descends.

[0094] Figure 12, which will be described in more detail below, illustrates another embodiment of the present disclosure in which cooling coil sections can be held at different vapor pressures using only a single vacuum source and without the use of multiple pressure regulators. Instead, the configuration of the vertical piping 170 connecting the coil sections is varied to create an intentional pressure drop between the storage tanks. Longer pipe lengths or the addition of pipe fittings create greater resistance to the flow of vaporized refrigerant as the vaporized refrigerant moves from a given refrigerant storage tank to the vacuum source. This resistance, in turn, creates different vapor pressures in the horizontal coil sections.

[0095] Figure 12 shows an alternative embodiment of the apparatus in Figure 8, in which the refrigerant vapor flow is carried together via vertical piping 170 to collect on and outside the container or vessel. The diameter of the vertical piping 170 carrying the vapor flow may be smaller than the diameter of the horizontal pipes forming each storage tank section 80, thereby increasing the velocity of the escaping refrigerant vapor flow. This helps to avoid condensation in the vertical piping 170, which should prevent the vaporized refrigerant from escaping the cooling coils. Furthermore, there is a filling and drain line 171 connecting each manifold 112 to a common refrigerant filling and drain line 116. The orientation of the piping forming the filling and drain line 171 can be varied based on a desired level of refrigerant 82 to be held in each manifold 112 after system draining.

[0096] For example, adding a single 90-degree elbow joint in the piping between horizontal coil sections creates an additional pressure drop of 0.0081 psi, assuming a flow rate of 10 CFM of ethanol refrigerant at 0.3 psi and 38.7°F inside a 4 ft long, 0.25 inch diameter pipe. This pressure drop is equivalent to a change of approximately 0.8°F in the vaporization temperature inside adjacent horizontal coils. A similar mechanical arrangement can be used to generate a pressure difference between horizontal sections of heating coils using a condensing working gas.

[0097] According to another aspect of this disclosure, the cooling coil section is maintained at a common vapor pressure using a single pressure regulator and a common vacuum source. Nevertheless, the horizontal coil section houses different types of refrigerants, which are selected to vaporize at different temperatures and a common vapor pressure. During operation, the flow of refrigerant vapor leaving the coil is therefore multi-component, and recovery is affected upstream of the vacuum pump using a condenser and decanter. After decanting, the refrigerant is returned to the designated horizontal coil by separate pumps, each designated for one type of condensed refrigerant. Similar mechanical configurations can be used for different types of condensing working gases.

[0098] 2. Use of condensing working gas or vaporized refrigerant to indicate the spatial location of heat transfer. According to another aspect or embodiment of this disclosure, a temperature probe or sight glass, pressure, and vacuum gauge or other instrument may be used to observe or determine the condensation rate or vaporization rate of the fluid in the conduit. The vaporization rate is indicated by the increased movement of the liquid refrigerant or by bubbles formed on the inner surface of the temperature control conduit or heat exchanger. These bubbles first form on the surface of the refrigerant storage tank and then, finally, separate and move upward toward the upper space. An operator, such as a brewer, may have visual or instrument-acquired data to determine where heat is being generated by observing the vaporization process using a sight glass or instrument and observing where the fluid movement occurs or where bubbles are forming. The condensation rate is indicated by the presence of liquid due to the condensation of the working gas.

[0099] Some brewers turn off their cooling systems because they do not have a precise way to protect against localized thermal events and do not want to risk batch-wide thermal shock through the activation of the cooling jacket. This disclosure can also provide continuous guidance for localized heat production through the unexpected presence of refrigerant in a vacuum pump or compressor. For example, the guidance could be used to signal a brewer to take corrective action to re-homogenize the tank. Similarly, the unexpected presence of condensed working gas at the outlet of a heating coil indicates that fermentation requires additional heat input to maintain the temperature.

[0100] Furthermore, the generation of localized heat volume surrounding a working gas storage tank or refrigerant storage tank can provide useful information for troubleshooting the operating condition of the tank or container. For example, if a vaporizer is placed inside the tank or container and the heat volume of the device is configured to allow a temperature difference of 5°F or less from a setpoint, the presence of vaporized refrigerant indicates that at least some portion of the internal volume of the tank or container exceeds this temperature difference. This information is useful because it indicates that modifications to the stirring speed, stirrer type, baffle location, etc., should be affected and should maintain the operating temperature of the tank or container below the desired setpoint temperature.

[0101] According to one aspect of the present disclosure, a working gas storage tank or refrigerant storage tank having a sight glass is placed in contact with the outside of a tank or container. For cooling coils, visual observation of the movement of liquid refrigerant and bubble formation provides indication of local heat transfer from the medium to the refrigerant. The relative magnitude of local heat transfer is indicated by a visual comparison of the movement of liquid refrigerant and bubble formation between horizontal sections. A similar comparison may be affected for working gas condensation, where the condensation of gas from vapor to liquid is visually observed.

[0102] According to another aspect of this disclosure, the refrigerant vaporizer may consist of condensers mounted on the outlet lines of each horizontal storage tank section and between this section and a common vacuum source. During system operation, the liquid levels in these condensers can be monitored. Using the size of the condensers, as well as known values ​​of the vaporization density and latent heat of a given refrigerant, a quantitative value of heat transfer from the medium to each refrigerant coil section can be calculated.

[0103] For example, assuming an upright cylindrical condenser with a 12-inch diameter, a 1-inch level change is equivalent to approximately 0.21 lbs of ethanol. This is equal to approximately 76 BTU of heat transferred from the medium to the refrigerant storage tank. This same calculation can be used for working gas condensers. In this example, the volume of condensed liquid present in each trap directly corresponds to the heat released from the storage tank to the medium.

[0104] According to a further aspect of the present disclosure, a refrigerant vaporizer having a pressure transmitter is mounted on the outlet line of each horizontal storage tank section. The section can be isolated from the vacuum source via an automatic valve, and when isolated, an increase in the refrigerant vapor pressure of the horizontal section indicates local heat generation near this section. For an isolated working gas, a decrease in the refrigerant vapor pressure of the horizontal section indicates that the medium near this section required additional heat.

[0105] 3. Use of a buffer medium to improve the consistency of heat transfer. Here, the buffer medium is in thermal contact with both the working gas storage tank or the refrigerant storage tank and the medium. Figure 13 shows a system 132 that uses a coil or a series of connected coils 134 mounted on the outside 136 of a container 138, such as a covered fermentation tank. The medium 140 is contained within the container 138. In this embodiment, the coils 134 mounted on the outside 136 of the container 138 provide contact between the buffer medium and both the container 138 and the medium 140 inside the container 138.

[0106] For a cooling coil, heat is transferred sequentially: first from the medium to the tank or container wall, then through the wall to the buffer medium, then from the buffer medium to the coil wall, and finally through the coil wall to the coolant. For a heating coil, this heat transfer process is reversed, with the heat flow starting in the working gas and ending in the medium. Quantitatively, the coil spacing equation is modified to account for the added resistance of both the buffer medium and the surface surrounding it.

[0107]

number

Number

Number

[0108] ​​It may be more appropriate to use the thermal transfer coefficient H of the buffer medium with units of K, which takes into account boundary layer effects on both the outer and inner surfaces of the coil of the buffer housing. For the sake of simplicity of derivation, these effects have been combined into a value of K² with units of W / m*K per unit length of the horizontal section.

[0109] Referring to Figure 14, for a given horizontal grid section, its mechanical design must allow for a desired heat transfer coefficient subject to additional thermal resistance. When the working gas storage tank or refrigerant storage tank is located outside a tank or container, the air between adjacent coils may take into account the buffer medium and the walls of the tank or container surrounding the surface of the buffer medium. Ideally, the buffer medium should still transport heat with minimal resistance and be made of a construction material favorable to the desired heat transfer coefficient. The construction material of the buffer medium housing must also not affect the medium.

[0110] The buffer medium can also function to extend the radius of localized heat volume, thereby reducing the temperature gradient between adjacent working gas or refrigerant coils. This is useful in fermentation tanks where it is desirable to maintain a constant temperature across the entire profile outside the tank, for example, to provide a constant temperature environment at the external boundary of the medium and to help prevent thermal shock due to the activation of the temperature control system.

[0111] According to another aspect of this disclosure, the apparatus shown in Figure 13 may be placed inside a tank or container. In this example, the buffer medium is in thermal contact with both the working fluid or refrigerant coil and the medium. The localized heat volume outside the storage tank is then expanded beyond the normally generated heat volume when the coil is submerged, even without the buffer medium and its housing.

[0112] For example, if a stainless steel ethanol refrigerant vaporization coil with an inner diameter of 1 inch and an outer diameter of 1.15 inches is submerged in a tank or container with a centerline-to-centerline distance of approximately 8.75 inches, the calculated temperature gradient at the midpoint between adjacent coils is approximately 8°F. If the centerline distance between coils is maintained, but an aluminum buffer medium is used with a stainless steel buffer medium housing with an inner diameter of 1.5 inches and an outer diameter of 1.625 inches, the calculated temperature gradient at the midpoint between adjacent coils drops to approximately 6.35°F.

[0113] 4. Generating internal flow of vaporized refrigerant to improve heat transfer through vapor pressure fluctuations. According to further aspects of this disclosure, the mechanical design of the cooling coil provides agitation of the cooling fluid inside the cooling coil tube itself, further improving heat transfer from the cooling liquid to the vapor interface within the coil. The agitation arises from a mechanical design in which a common refrigerant vapor space is linked to at least two ends of a coil filled with liquid refrigerant. When the liquid refrigerant vaporizes due to the vacuum, the generated vapor moves toward the common vapor space, and this movement causes agitation of the refrigerant liquid volume between the vapor source and the common upper space. Nevertheless, since the liquid refrigerant volume is connected to the common upper space at two or more locations, vapor generation causes a portion of the liquid volume to move in the opposite direction to the direction in which the vapor is moving, and this portion of the liquid can move to fill a portion of the common upper space. The result is that a portion of the liquid refrigerant within the coil subsequently moves toward the inner surface of the coil. The movement of the liquid refrigerant enhances the absorption of the refrigerant vapor generated on the inner surface of the coil into the refrigerant liquid, thereby improving heat transfer from the medium outside the coil to the refrigerant contained within the coil. For example, assuming an ethanol refrigerant, a vacuum level of 0.248 psi to 0.265 psi would be required, which is equivalent to the fermentation temperature of 68°F to 72°F for beer ale.

[0114] The above is shown in Figure 15, which shows a vacuum coil and storage system 142 consisting of two coils, a first coil 144 and a second coil 146, connected to a common vacuum coil storage tank 148, with a vacuum homogenization line 152 at the top 150 of the common vacuum coil storage tank 148. The first and second coils 144 and 146 each have first ends 154 and 156, respectively, connected to individual first and second ports 158 and 160 in the empty upper space at the top 150 of the storage tank 148. Furthermore, the first and second coils 144 and 146 each have second ends 162 and 164, respectively, connected to a common port 166 at the second end 168, or to the liquid-filled portion of the storage tank 148. Essentially, when a vacuum is activated, the liquid in coils 144 and 146 begins to oscillate relative to two connection ports 158 and 160 located at the top 150 of the storage tank 148. When observed through clear coil tubing, the liquid appears to attempt to escape through one side of the top connection ports 158 and 160, then be pulled back, and then attempt to escape through the other side of the top connection, but never succeed in escaping through either connection. This must be the observed oscillating motion. The storage tank is mechanically configured to replenish with vaporized liquid refrigerant and maintain a constant level of liquid refrigerant within the coil relative to the start and end positions of the oscillation.

[0115] 5. Preheating of the refrigerant When the system is refilled with refrigerant, the refrigerant can be heated to a temperature higher than the current temperature of the medium. Once introduced into a refrigerant storage tank, the heat is conducted to the medium through the walls of the storage tank as the refrigerant cools, warming the medium. The refrigerant is then vaporized when cooling is desired. Thus, both heating and evaporative cooling can be affected by the same refrigerant vaporizer.

[0116] Figure 16 is an adaptation of Figure 7 described above and shows a system 70 having a vacuum source 92, a fermentation tank 74, a fermentation tank temperature transmitter TT, a refrigerant storage tank 78, a refrigerant supply pump 106, a refrigerant tank 102, and a refrigerant supply temperature transmitter TT. The temperature of the refrigerant in the refrigerant tank 102 is controlled using a heating coil 101 and a cooling coil 103. Heating of the medium is achieved by adjusting the setpoint temperature of the refrigerant to be higher than the current temperature of the medium, and then supplying this refrigerant to the refrigerant storage tank.

[0117] 6. Heating and cooling using heat transfer media Temperature control of the medium can be achieved by a continuous flow of heat transfer fluid through a working gas or refrigerant device. Nevertheless, the temperature profile of the heat transfer fluid will vary throughout the coil storage tank, proportional to the rate of heat transfer to and from the medium and to specific locations. This temperature gradient does not exist with condensing working gas or vaporizing refrigerant, as both types of phase transitions provide a constant temperature heat source or sink throughout the same coil. However, for applications where coil temperature fluctuations are acceptable, heating or cooling via a heat transfer fluid flow can be a viable alternative to heating via working gas condensation or cooling via refrigerant vaporization. In this example, the coil spacing of the heating or cooling coils is defined by the same equation as in the condensing working gas or vaporizing refrigerant method, so as to most closely approximate the performance of the condensing working gas or vaporizing refrigerant.

[0118] Without using a condensing working gas or a vaporizing refrigerant, temperature fluctuations across the entire coil are minimized when the flow of the heat transfer medium is high and the flow can be characterized as turbulent. At a constant heat flux, increasing the flow rate of the heat transfer medium volume shortens the time for heat absorption or release, so that this volume does not heat up or cool down as much across a fixed-length coil section. Turbulence inside the coil section can increase the heat transfer coefficient of the heat transfer medium so that the coefficient approaches that of a condensing working gas or a vaporizing refrigerant.

[0119] For example, Figure 17 is essentially a modified Figure 16, showing a refrigerant vaporizer having an inlet and outlet for a heat transfer medium. The flow rate of the heat transfer medium can be adjusted using a variable-speed pump 106, the inlet temperature is controlled using temperature indicators TT on the heating coil 101, the cooling coil 103, and the heat transfer medium supply tank 102, and the outlet temperature is monitored using temperature indicators TT in the piping connecting the refrigerant storage tank 78 and the condenser 96. The heat transfer medium temperature in the connecting piping is monitored, and the speed of the pump 106 is varied to ensure that the temperature drop or rise across the coil does not exceed a set value. This works best to protect the localized heat volume distribution created by the mechanical design of the refrigerant system by keeping the external temperature of the coil constant or close to it.

[0120] According to a further aspect of the present disclosure, the heat transfer medium is pumped in parallel through horizontal coils of either a working gas device or a vaporizer to reduce the temperature rise throughout each coil. The coil temperature at each outlet is monitored, and the flow rate of the heat transfer medium to each horizontal section is adjusted to bring the overall temperature change of the coil close to zero.

[0121] 7. Condensation of the working fluid for heating A refrigerant vaporizer performs process cooling of a medium by utilizing the minimum temperature gradient. The mechanical design of the refrigerant vaporizer creates a volume of the medium's heat reach that surrounds individual refrigerant storage tanks, and these tanks are configured such that the respective boundaries of the heat reach are at least continuous. The designer of the refrigerant vaporizer then selects the spacing between adjacent refrigerant storage tanks according to the acceptable temperature fluctuations inside the medium to be cooled. When operational, the refrigerant vaporizer effectively sets an upper limit on the acceptable temperature of the medium.

[0122] When the vaporized refrigerant inside the device is replaced by the condensing working gas, the device immediately reverses its function, heating the medium with a minimum temperature gradient. The volume of the medium's heat reach is maintained both in scale and in specific locations, and the volume also functions to set a lower limit on the medium's acceptable temperature. The equation for calculating the ideal coil spacing for a working gas condenser is identical to the equation for a refrigerant vaporizer, as derived in the example below.

[0123]

number

number

number

[0124] Note that the temperature T1 at the center of the working gas storage tank is now less than the temperature T2 at the outer edge of the volume within the heat reach of the medium, and the heat J generated by the medium per unit volume per unit time now remains negative, indicating that the medium is losing heat per unit volume per unit time. The changes in sign of both the temperature difference ΔT and the heat production J cancel each other out, and the expression inside the square root term always remains positive, providing a real solution for the value R3.

[0125] Referring to Figures 18 and 19, for a given horizontal grid tube section 200, its mechanical design must be such that it can supply the maximum heat required by the medium volume 202 surrounding the horizontal grid section 200, which has an outer boundary 204. This volume 202 can be approximated by assuming a cylindrical shape surrounding the horizontal grid section 200 with radius R3, which is a combination of the distance R2 from the centerline of the grid to the outside of the tube and the distance at R2 from the outside of the grid to the centerline between adjacent grids. The volume of the mechanical grid is then subtracted from the total volume of the medium-filled container in order to calculate the volume of medium required by the heat.

[0126] R1 is the inner radius of the grid tube and should be selected in conjunction with the horizontal length L of the horizontal grid section 200 to provide sufficient surface area for heat transfer from the grid structure to the medium. As with refrigerant vaporizers, design considerations must be made for pressure drops in the space above the grid during system operation. However, unlike refrigerant vaporizers, any condensed working gas must be quickly removed in order to maintain the internal grid tube surface free from obstacles that could reduce the condensation rate, so there should only be a minimum liquid level in the horizontal grid tube section 200.

[0127] Furthermore, similar to refrigerant vaporizers, the design and mathematical methods of horizontal grid tube sections can be adapted for use outside the container. Additional heat transfer resistance created by the container walls and medium (e.g., air) surrounding the horizontal section must be considered. These resistances can be described through reduced values ​​of h1, h2, or k1 in the spacing equation, or through a more rigorous treatment of heat transfer resistance, such as that shown in the modified spacing equation seen in Embodiment 3 of this disclosure. Often, the resistance terms h1, h2, or k1 are modified to reflect empirical data, but it is most practical to keep calculations to a minimum.

[0128] The ideal spacing of horizontal grid tube sections for a working gas condenser is still the same as that calculated by the right-angle shape of the refrigerant vaporizer. Figures 20, 21, and 22 show alternative geometric configurations in which the spacing between grid sections can be widened, but these configurations risk insufficient heating, which could cause parts of the medium to fall below the design temperature range. Figure 20 is a cross-sectional view of multiple heating volumes with minimum reach, Figure 21 is a cross-sectional view of multiple heating volumes with partial reach, and Figure 22 is a cross-sectional view of multiple heating volumes with full reach.

[0129] Figure 23 shows a system 210 for controlling the temperature of a medium 212 by working gas condensation. In this representative embodiment, the system includes a container 214 having an exterior 216 and an interior 218. At least one working gas storage tank 220 is associated with the container 214, and the working gas storage tank 220 includes at least one storage tank section 222 assembled to hold the working gas 224 in an internal storage tank space 226. In this embodiment, as clearly shown in Figures 25 and 26, there are multiple storage tank sections 222, each storage tank section 222 having a wall 228 with an exterior surface 230 assembled to provide a volume of heat reachable by the medium 212 in the container 214, thereby causing a thermal change in the volume of the medium 212 in the container 214, as described above in relation to Figures 18 and 22, and which will be described more fully below.

[0130] Each of the storage tank sections 222 has an internal storage tank space 226 of the storage tank section 222 which is fluidly connected to at least one other internal storage tank space 226 of an adjacent storage tank section 222, and the multiple storage tank sections 222 are spaced apart from adjacent storage tank sections 222, each having a volume of a medium heat reach range with each boundary of a heat reach range that will be at least continuous.

[0131] The system 210 further includes a gas cylinder 240 for supplying working gas to the storage tank section 222, and a working gas pressure device 242 for adjusting the working gas pressure within the storage tank section 222. Each storage tank section 222 is configured to form a vapor space 232 within each storage tank section 222 in response to receiving working gas 224 and to response to the adjustment of the pressure of the working gas 224 by the working gas pressure device 242, allowing working gas condensation at or near a selected temperature (e.g., higher than 202) for a volume of the medium 212 in a container 214 thermally connected to the respective storage tank section 222, within the range of the medium's heat reach.

[0132] The working gas pressure device 242 can be implemented using readily available commercial equipment and will therefore not be described in detail herein. In short, the working gas pressure device 242 includes a gas cylinder 240 fluidly coupled to a working gas storage tank 220. Ideally, both a pressure regulator 244 and an accumulator 246 are positioned between the gas cylinder 240 and the working gas storage tank 220. Control of the pressure regulator 244 can be implemented manually, or more preferably by automatic control in a controller 248 that processes signals from the sensors using sensors and a computer processor and transmits control signals to the pressure regulator 244 in response to the sensor signals.

[0133] In the embodiment shown in Figure 23, a condensate trap 250 is provided to remove condensed working gas, such as R-134a. The condensate trap 250 is fluidly connected to a working gas storage tank 220 via an outlet pipe 252, which can be gravity-fed to provide a continuous or intermittent supply of condensed working gas to a condensate receiver tank 254. Ideally, the condensate receiver tank 254 has a level transmitter LT that detects and transmits an indication of the volume of condensate in the condensate receiver tank 254 to avoid the application of back pressure that could interfere with the proper functioning of the condensate trap 250. The pressure in the working gas storage tank 220 is maintained at a set pressure by a working gas pressure device 242, and the condensed working gas is removed to the condensate trap 250 by gravity drain.

[0134] Figure 24 shows an alternative embodiment of system 260 to system 210 shown in Figure 23. The working gas is continuously supplied to the working gas condenser 262 through the use of a compressor 264, an evaporator 266, a throttle device 268, a receiver 270 with variable heat removal, and a controller 248. This embodiment largely reflects the function of a conventional cooling system, but the refrigerant is replaced by the working gas. In this embodiment, the working gas is compressed by the compressor 264, condensed in the working gas condenser 262 and receiver 270, expanded through the throttle device 268, evaporated in the evaporator 266, and then returned to the compressor 264. The controller 248 is provided for system automation.

[0135] The receiver 270 can perform variable heat removal based on the condensation rate of the upstream working gas condenser 262. Variable heat removal is necessary to ensure that a constant volume of condensed working gas is supplied to the throttle device 268. For example, a cell culture reactor requires different scales of heat input to maintain its temperature based on its current lifecycle phase, and therefore can produce condensed working gas of variable flow rates and phases at the outlet of the working gas condenser 262. Nevertheless, the embodiment shown in Figure 24 functions optimally with a constant heat load such that both the flow rate and phase of the working gas are identical at the input to the throttle device 268, evaporator 266, and compressor 264, respectively. Variable heat removal in the receiver 270 adds additional condensation to the system when needed, resulting in downstream stability in the required phases and flow.

[0136] Furthermore, the alternative system 260 shown in Figure 24 can be modified for applications using a refrigerant vaporizer. In this example, the working gas condenser 262 and the receiver 270 with variable heat removal are replaced by a conventional condenser, and the evaporator 266 is replaced by a refrigerant vaporizer and a receiver with variable heat addition. The receiver with variable heat addition serves a similar purpose to the receiver 270 with variable heat removal in that it helps ensure a constant flow rate and phase of evaporated refrigerant to the downstream compressor 264, which is susceptible to the variable heat output of the medium being cooled.

[0137] As shown in Figure 25, in one embodiment, the working gas storage tank 220 has a manifold 234 connected to each of the storage tank sections 222 for fluid connection to the working gas supply line 236 and the condensate drain line 238, the manifold 234 enabling system liquid drain to the condensate trap 250 and the condensate receiver 254. Multiple storage tank sections 222 may be connected together in series, in parallel, or in a combination of series and parallel arrangements. In one embodiment, the working gas storage tank 220 comprises a grid of storage tank sections 222. Each storage tank section 222 is held in place by vertical supports 239, similar to the manifold 234. Each storage tank section 222 is designed and positioned for gravity drain of condensed working gas to the condensate drain line 238 via an inclination of the storage tank bottom 241.

[0138] According to another aspect of this disclosure, the working gas storage tank 220 may be located outside the container 214 shown in Figure 27.

[0139] Figure 28 shows an alternative embodiment of the apparatus of Figure 25. Here, a working gas storage tank 260 is provided, comprising a plurality of storage tank sections 262 connected in series by a vertical riser 264 to form a continuous arrangement having an uppermost input port 266 into which working gas 270 enters. A condensate drain line 268 is provided at the other end, enabling system drain to a condensate trap 250 and a condensate receiver 254. In this embodiment, the working gas 270 enters the input port 266 at the top of the system, and the liquid condensate 272 is removed by gravity at the bottom through the drain port 268. The working gas storage tank 260 must be tilted downward to enhance the gravity drain of condensate to the drain port 268. This coil should be suitable for use for heating or cooling a medium via the circulation of a heat transfer medium in either direction of the input port 266 or the drain port 268.

[0140] During operation, the working gas 276 is introduced into the working gas storage tank 260, and the pressure of the working gas 276 in the working gas storage tank 260 is adjusted to allow the working gas to condense at or near a selected temperature within the heat reach of the volume of the medium in the container thermally connected to each storage tank section 262, relative to the volume of the medium 274.

[0141] The system operation requires that the working gas condense uniformly, or preferably at the same temperature, throughout the coil. Furthermore, the volume of the working gas must be maintained throughout the coil sufficiently to remove the heat generated by the medium through vaporization. Proper orientation of the coil relative to gravity ensures that the liquid volume of the condensed working gas in the coil matches the design intent, allowing for rapid drainage into the trap below and keeping the internal surface area of ​​the coil free of liquid obstructions that could reduce the condensation rate. The metallurgy of the coil must be selected so as not to adversely affect the quality of the medium to be heated, and the coil should be cleaned between uses to avoid possible contamination of the new medium to be heated. The working gas pressure should result in working gas condensation at or as close as possible to the desired temperature of the medium to be heated, thus avoiding possible thermal shock to the medium.

[0142] When gas cylinders are used for batch supply of working gas, the working gas supply must be available at a pressure higher than the coil requirements, and the system design must allow for variable flow rates of working gas at the inlet to the system. This may be influenced by the use of an upstream accumulator to ensure a constant availability of a large volume of working gas held at the desired pressure. The condensate trap and receiver must also be properly sized so that the condensed working gas does not rise to a high liquid level in the coil drain piping, obstructing the internal surface area of ​​the coil available for heat transfer via condensation. The coil must also be carefully positioned in the correct orientation relative to gravity to allow for proper draining and prevent liquid buildup in the horizontal section.

[0143] When using a compressor for continuous operation, the proper orientation of the coil relative to gravity ensures optimal system performance, as the working gas reservoir systematically drains the condensed liquid. The compressor's performance must be monitored for the heat production profile of the medium over time. Most importantly, the compressor must be able to operate continuously with a variable flow rate of condensed working gas and throughout the desired range of working gas inlet pressure. Cell culture, for example, can vary its heat production rate depending on both time and batch size. System monitoring must be robust enough to adjust system operation to unexpected fluctuations in process variables without risking damage to the compressor and associated components.

[0144] The choice of working gas depends on the heat production profile of the medium to be heated and the optimal production temperature, in relation to the choice of heating equipment and control method. Ideally, the working gas also condenses at a pressure greater than atmospheric pressure (14.7 psia). This eliminates the need to maintain a system environment below atmospheric pressure, which is particularly difficult because air leakage into the system is common throughout the components and fittings, and the use of a vacuum source to compensate removes the working gas from the coil before it has a chance to condense.

[0145] The pressure drop between the working gas source and the coil must be calculated according to the system geometry to ensure that the working gas condenses at the desired temperature. Operationally, the working gas pressure corresponds to the working gas condensation temperature, since the working gas condensation temperature is constant during the phase change. The objective is to control the pressure of the working gas in the coil at a specific condensation temperature, at or near the set temperature of the medium to be heated.

[0146] For wine fermentation, the common maximum permissible temperature range is 64–77°F for red wine and 50–59°F for white wine. Assuming an R-134a working gas and compressor combination, these temperature ranges correspond to vapor pressures of approximately 77.10–96.11 psia for red wine and 59.98–70.61 psia for white wine. For beer fermentation, the common maximum permissible temperature range is 60–70°F for ale and 45–55°F for lager. Assuming an R-134a working gas and compressor combination, these temperature ranges correspond to vapor pressures of approximately 71.87–85.48 psia for ale and 54.62–65.72 psia for lager.

[0147] The system must also be cooled throughout the fermentation cycle. Primary fermentation for both red and white wines generally takes 3 to 5 days. For beer, primary fermentation generally takes 1 to 2 weeks for ales and 1 to 2 months for lagers.

[0148] 8. Intermediate medium on the coil surface The spacing equations for working gas storage tanks or refrigerant storage tanks can be modified to take into account intermediate media that will be placed in contact with both the surface of the working gas storage tank or refrigerant storage tank and the medium. Intermediate media may be useful, for example, as a disposable layer mounted outside the coil to prevent undesirable contamination from previous fermentation, or as a method to alter the external metallurgy of the coil when there is competition between the metallurgy of the coil and the medium that will be heated or cooled.

[0149] In sequence, heat is conducted in the cooling coil first from the medium to the intermediate medium, then from the intermediate medium to the coil walls, and finally through the coil walls to the coolant. For the heating coil, this heat transfer process is reversed, starting with the working gas and ending with the medium. Quantitatively, the coil spacing equation is modified to account for the added resistance of the intermediate medium.

[0150]

number

number

number

[0151] Referring to Figure 29, for a given horizontal grid section, the mechanical design must have a desired heat transfer coefficient, subject to additional thermal resistance. Ideally, the intermediate medium should transport heat with minimal resistance and be made of a construction material favorable to the desired heat transfer coefficient. Furthermore, the construction material of the intermediate medium must not affect the surrounding medium that will be heated or cooled. The working gas storage tank or refrigerant storage tank, including the intermediate buffer, may be located inside or outside the tank or container.

[0152] 9. Combination of working gas condensation and refrigerant vaporization coil A refrigerant vaporizer controls the temperature of the medium by preventing the medium volume from exceeding a high boundary temperature. Using the same coil spacing equation, a working gas condenser controls the temperature of the medium by preventing the medium volume from exceeding a low boundary temperature. Both types of devices can be combined inside a tank or container to control the temperature of the medium between high and low boundary temperatures.

[0153] Figure 30 shows an adjacent refrigerant storage tank designed so that the media outside the storage tank never exceeds a high boundary temperature of 72°F. Figure 31 shows an adjacent working gas storage tank designed so that the media outside the storage tank never falls below a low boundary temperature of 68°F. The internal grid temperature of the refrigerant and working gas storage tanks is 70°F.

[0154] Figure 32 shows a combination of the refrigerant storage tank shown in Figure 30 and the working gas storage tank shown in Figure 31. The storage tanks are positioned such that the end of the thermal reach of one storage tank lies in the center of adjacent storage tanks of different types. Thus, a refrigerant storage tank that prevents the temperature of the surrounding medium from exceeding 70°F to 72°F is positioned such that the end of its thermal reach lies in the center of an adjacent working gas storage tank that prevents the temperature of the surrounding medium from falling below 68°F to 70°F.

[0155] Assuming radial heat transfer from each storage tank through the same medium, the temperature at the lower boundary of the cooling vaporizer never falls below the temperature at the higher boundary of the working gas condenser, and the temperature at the higher boundary of the working gas condenser never exceeds the temperature at the lower boundary of the cooling vaporizer, thus minimizing the risk of interference between the two temperature control systems. Consequently, no spatial temperature gradient is formed in which the condenser should provide heat to the vaporizer volume within the cooling reach, nor is a spatial temperature gradient formed in which the vaporizer removes heat from the condenser volume within the cooling reach.

[0156] 10. Use of working gas condensation and refrigerant vaporization coil inside a stirred tank. A refrigerant vaporizer controls the temperature of the medium by preventing the medium volume from exceeding a high boundary temperature. Using the same coil spacing equation, a working gas condenser controls the temperature of the medium by preventing the medium volume from exceeding a low boundary temperature. Both types of devices can be used individually to control the temperature of the medium inside a tank or container, or they can be combined inside the tank or container to control the temperature of the medium at or between high and low boundary values.

[0157] The use of either or both of the devices in a tank being agitated improves the probability of successful heat transfer from the medium to the refrigerant vaporization storage tank, or from the working gas condensation storage tank to the medium. Mathematically, this increase in probability is clearly indicated by the increase in H2, the medium heat transfer coefficient including boundary layer effects. According to the coil spacing equation, the increase in H2 then increases the value of R3, which is the radius from the center of the horizontal grid section to the outside of the medium volume. Practically, the use of agitation in a tank or container reduces the coil surface area required to maintain the desired volume of the cooling reach inside the tank or container. For example, ethanol refrigerant, tubular storage tanks in 2" OD sanitary storage tanks, and refrigerant vaporizers used in wine fermentation with a temperature difference of 10°F have an ideal grid spacing of roughly 12 inches. When the wine tank or container is agitated, the value of H2, the medium heat transfer coefficient including boundary layer effects, should increase from 140 W / m²*K to 1000 W / m²*K. According to the spacing equation, this change alters the ideal grid spacing to roughly 21 inches.

[0158] It is often useful to further subdivide H1, the heat transfer coefficient of the refrigerant or condensing working gas including the boundary layer effect, and H2, the heat transfer coefficient of the medium including the boundary layer effect. This subdivision allows for an improved analysis of the effect of agitation on the heat transfer coefficient. For example, if the grid spacing increases due to medium agitation, the available coil surface area decreases, so deposits have a larger proportional effect on heat transfer. Impeller design, speed, and spatial position can also have a significant impact on the coil heat transfer coefficient in an agitated tank or container through changes in the heat transfer film coefficient. Typical subdivisions for agitated refrigerant vaporizers are as follows: 1 / U=1 / HM+1 / HROFC+1 / HROF+1 / HR+1 / HRIF+1 / HRIFC+1 / HF U = Total heat transfer coefficient (W / m^2 * K) HM = Heat transfer coefficient of the medium (W / m^2 * K) HROFC = Heat transfer coefficient of the film on the outside of the storage tank (W / m^2*K) HROF = Heat transfer coefficient of deposits on the outside of the storage tank (W / m^2*K) HR = Heat transfer coefficient of the storage tank (W / m^2*K) HRIF = Heat transfer coefficient of deposits on the inside of the storage tank (W / m^2*K) HRIFC = Heat transfer coefficient of the film on the inside of the storage tank (W / m^2*K), and HF = Refrigerant heat transfer coefficient (W / m^2 * K).

[0159] It should be noted that the overall heat transfer coefficient U represents the complete heat transfer coefficient from the medium to the coolant, taking into account the effects of the thermal conductivity H1, H2, and K1 of the lattice construction materials, as used in the spacing equation.

[0160] These and other modifications can be made to the embodiments in terms of the detailed description above. In general, the terms used in the following claims should not be construed as limiting the claims to any particular embodiment disclosed herein and in the claims, but rather as encompassing all possible embodiments, together with the full scope of any equivalent to which such claims are given. Thus, the claims are not limited by this disclosure.

Claims

1. A system for controlling the temperature of a medium by working gas condensation, A container having an exterior and an interior, At least one working gas storage tank associated with the container, the at least one working gas storage tank having at least one storage tank section configured to hold working gas, each at least one storage tank section having a wall assembled such that its outer surface is thermally connected to the volume of the medium in the container, transmits thermal changes to the volume of the medium in the container, thereby providing a volume of heat reachable by the medium in the container, the volume of heat reachable by the medium having an outer boundary, A condenser for adjusting the working gas pressure in at least one working gas storage tank, Equipped with, The at least one working gas storage tank is configured to form a vapor space in each of the at least one storage tank section in response to receiving working gas and in response to adjustment of the working gas pressure of the condenser, in order to enable working gas condensation at or near a selected temperature of the volume of the medium in the container thermally connected to the volume of the medium, within the range of medium heat reachable by the medium. system.

2. The system according to claim 1, wherein the system comprises a plurality of partitioned storage tank sections, each having an internal storage tank space, the at least one storage tank section being fluidly connected to at least one other internal storage tank space of an adjacent storage tank section, and the plurality of storage tank sections are arranged at intervals from adjacent storage tank sections having at least a continuous volume of a medium heat reachable range, the respective outer boundaries of the heat reachable range of each storage tank section.

3. The system according to claim 2, further comprising a working gas source fluidly connected to the working gas storage tank and the condenser, wherein the system is configured to send working gas to the working gas storage tank in response to a change in pressure in the working gas storage tank, as adjusted by the condenser.

4. The system according to claim 2, wherein the plurality of storage tank sections are connected together in series, in parallel, or in a combination of series and parallel arrangements.

5. The system according to claim 2, wherein the working gas storage tank comprises a grid of horizontally partitioned storage tank sections.

6. The volume of the heat-reachable medium surrounding the grid of the horizontally partitioned storage tank section within the container has a radius R3 determined as follows: [Math 1] Here, H1 = Working gas heat transfer coefficient including boundary layer effect (W / m ２ *K), H2 = Heat transfer coefficient of the medium including boundary layer effect (W / m ２ *K), J = Heat generated per unit volume per unit time by the medium (W / m³) ３ ), K1 = Thermal conductivity (W / m * K) of the material used to construct the working gas storage tank wall. R1 = radius (m) from the center of the storage tank section to the inside of the storage tank section wall. R2 = radius (m) from the center of the storage tank section to the outside of the storage tank section wall. R3 = Radius (m) from the center of the storage tank section to the outer boundary of the heat-reachable area of ​​the medium. T1 = Temperature of the working gas at the condensation point (K), and T2 = Temperature of the medium at the outer boundary of the heat reach range (K) The system according to claim 5.

7. The minimum distance between the centers of adjacent compartmentalized storage tank sections is at least [Math 2] The system according to claim 6.

8. The system according to claim 1, wherein the at least one working gas storage tank is located inside the container.

9. The system according to claim 1, wherein the at least one working gas storage tank is located outside the container.

10. The system according to claim 1, further comprising a variable-speed pump for moving the working gas through the working gas storage tank and condenser.

11. A method for controlling the temperature of a medium by working gas condensation, A step of providing an apparatus for controlling the temperature of the medium by condensation of a working gas, A container having an exterior and an interior, At least one working gas associated with the container, wherein at least one working gas storage tank has at least one storage tank section configured to hold the working gas, and each at least one storage tank section has a wall assembled such that its outer surface is thermally connected to the volume of the medium in the container, transmits thermal changes to the volume of the medium in the container, thereby providing a volume of heat reachable by the medium in the container, and the volume of heat reachable by the medium has an outer boundary, with at least one working gas, A condenser for adjusting the working gas pressure in at least one working gas storage tank, The step includes providing The at least one working gas storage tank is configured to form a vapor space in each of the at least one storage tank section in response to receiving working gas and in response to adjustment of the working gas pressure condenser, so as to enable working gas condensation at or near a selected temperature of the volume of the medium in the container thermally connected to the volume of the medium, within the range of medium heat reachable. Steps and The steps include introducing working gas into the at least one working gas storage tank so as to partially occupy the at least one storage tank section of the at least one storage tank section, The steps of adjusting the working gas pressure in the at least one storage tank section to enable working gas condensation at or near a selected temperature of the volume of the medium within the container thermally connected to the at least one storage tank section, Methods that include...

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