The disclosed embodiments relate to the field of fluid coolers, and to methods and apparatus for cooling fluids.
In the dental and medical fields, among others, equipment may be sterilized using a sterilizer. Some sterilizers, such as cassette and chamber autoclaves, use high temperature steam to sterilize equipment. At least some of these apparatus include an outlet for the disposal of exhaust steam or hot liquid fluid.
Disposing of exhaust steam or hot liquid directly into a sewer or drain pipe is prohibited in many municipalities. In many cases, steam or hot liquid must be cooled to a liquid no hotter than 65° C. before it can be legally discharged into a sewer or drain pipe. Moreover, many municipalities impose strict backflow prevention policies for protecting potable water from contamination.
In a first aspect, there is a fluid cooler comprising a container for a liquid transfer medium. The container may include first and second hot fluid inlets, first and second cooled liquid outlets, a cooling liquid inlet, and a cooling liquid outlet. A first conduit may extend within the container and fluidly couple the first hot fluid inlet to the first cooled liquid outlet. A second conduit may extend within the container and fluidly couple the second hot fluid inlet to the second cooled liquid outlet. A third conduit may extend within the container and fluidly couple the cooling liquid inlet to the cooling liquid outlet. The first, second, and third conduits may be positioned to be at least partially submerged in the liquid transfer medium when the container contains the liquid transfer medium.
In some embodiments, the container may include a removable lid, and at least one of the first and second hot fluid inlets, the first and second cooled liquid outlets, the cooling liquid inlet, and the cooling liquid outlet may be located in the removable lid.
In some embodiments, the fluid cooler may further comprise a thermally sensitive flow regulator fluidly coupled to the third conduit.
In some embodiments, the flow regulator may include a valve operated by a thermally sensitive actuator.
In some embodiments, the flow regulator may positioned within the container such that the flow regulator is at least partially submerged when the container contains the liquid transfer medium.
In some embodiments, at least one of the first, second and third conduits may be at least partially coiled.
In some embodiments, one conduit of the first, second, and third conduits may include a coiled portion defining an interior volume; and at least one other of the first, second and third conduits may extend through the interior volume.
In some embodiments, the container may have a top, and a bottom. Each of the first, second, and third conduits may include a coiled portion. The coiled portion of the third conduit may be closer to the top of the container than the coiled portions of the first and second conduits.
In some embodiments, the fluid cooler may further comprise a discharge conduit which may extend exterior the container and may have a first end fluidly coupled to the cooling liquid outlet.
In some embodiments, the discharge conduit may include a second end exposed to open air.
In another aspect, there is a fluid cooler core comprising a container lid having an inward facing side, a hot fluid inlet, a cooled liquid outlet, a cooling liquid inlet, and a cooling liquid outlet, A first conduit may extend from the inward facing side and fluidly couple the hot fluid inlet to the cooled liquid outlet. A second conduit may extending from the inward facing side and fluidly couple the cooling liquid inlet to the cooling liquid outlet. When the container lid closes an opening to a container, the first and second conduits may extend into the container.
In some embodiments, the fluid cooler core may further comprise a thermally sensitive flow regulator fluidly coupled to the second conduit.
In some embodiments, the flow regulator may include a valve operated by a thermally sensitive actuator.
In some embodiments, at least one of the first and second conduits is at least partially coiled.
In some embodiments, one conduit of the first and second conduits may include a coiled portion defining an interior volume, and the other of the first and second conduits may extend through the interior volume.
In some embodiments, each of the first and second conduits may include a coiled portion, and the coiled portion of the second conduit may be closer to the lid than the coiled portion of the first conduit.
In some embodiments, the container lid may include a second hot fluid inlet, and a second cooled liquid outlet, and a third conduit may extend from the inward facing side and fluidly couple the second hot fluid inlet to the second cooled liquid outlet.
In another aspect, there is a method of condensing gas. The method may comprise directing a flow of cold liquid through a first conduit, the first conduit being at least partially submerged in a liquid transfer medium, to cool the liquid transfer medium; and directing a flow of hot gas through a second conduit, the second conduit being at least partially submerged in the liquid transfer medium, to condense the flow of steam into a flow of cold liquid condensate.
In some embodiments, directing a flow of cold liquid may comprise directing a flow of cold water from a municipal supply line through the first conduit. The method may further comprise discharging the flow of cold liquid into a municipal drain through open air.
In some embodiments, directing a flow of cold liquid may comprise directing a flow of cold water from a municipal supply line through the first conduit. The method may further comprise discharging the flow of cold liquid into a municipal drain through one or more of a double check-valve and a reduced pressure zone assembly.
In some embodiments, the method may further comprise regulating the flow rate of cold liquid with a thermally sensitive flow regulator at least partially submerged in the liquid transfer medium.
In some embodiments, directing the flow of steam may comprise directing a flow of steam discharged from a sterilizer through the second conduit.
In some embodiments, the method may further comprise directing a second flow of steam through a third conduit, the third conduit being at least partially submerged in the liquid transfer medium, to condense the second flow of steam into a second flow of cold liquid condensate.
The terms “an embodiment,” “embodiment,” “embodiments,” “the embodiment,” “the embodiments,” “one or more embodiments,” “some embodiments,” and “one embodiment” mean “one or more (but not all) embodiments of the present invention(s),” unless expressly specified otherwise.
The terms “including,” “comprising” and variations thereof mean “including but not limited to,” unless expressly specified otherwise. A listing of items does not imply that any or all of the items are mutually exclusive, unless expressly specified otherwise. The terms “a,” “an” and “the” mean “one or more,” unless expressly specified otherwise.
A description of an embodiment with several components in communication with each other does not imply that all such components are required. On the contrary a variety of optional components are described to illustrate the wide variety of possible embodiments of the present invention.
When a single element is described herein, it will be readily apparent that more than one element may be used in place of the single element. Similarly, where more than one element is described herein, it will be readily apparent that a single element may be used in place of the more than one element.
Reference is first made to
In the example shown, fluid cooler 100 includes a hot fluid inlet 104 fluidly coupled by a hot fluid conduit 106 to hot fluid source 102. Fluid cooler 100 is shown further including a cooled liquid outlet 108 fluidly coupled by a cooled liquid conduit 110 to a drain pipe 112. As shown, exhaust hot fluid from hot fluid source 102 is directed through hot fluid conduit 106 to fluid cooler 100. As used herein, and in the claims, a fluid is either liquid or steam, and a hot fluid has a temperature greater than a cooled liquid. Further, as used herein, and in the claims, steam refers to any gas which changes phase from gas to liquid at atmospheric pressure and a temperature in the range of 50° C. to 200° C. In one example, steam is water vapor having a temperature above 100° C.
In use, at least one embodiment of fluid cooler 100 cools the exhaust hot fluid from hot fluid source 102 (and if the hot fluid is steam then condenses it) into a cooled liquid which is then discharged through cooled liquid outlet 108 and cooled liquid conduit 110 into drain pipe 112. In at least some cases, the cooled liquid has a temperature at discharge of less than or equal to 65° C.
In some examples, hot fluid source 102 is a cassette autoclave which uses steam for sterilizing equipment, such as dental and medical equipment for example, and exhausts steam into hot fluid conduit 106. However, in alternative embodiments, hot fluid source 102 is any apparatus which outputs hot fluid and that can be fluidly coupled to fluid cooler 100. In some examples, hot fluid source 102 is a steam oven, a steam washer, a steam drier, or a washer/disinfector. In some cases, hot fluid discharged from hot fluid source 102 has a temperature between 85° C. and 300° C.
Fluid cooler 100 is shown including a container 114 for a liquid transfer medium 116. Container 114 can take any form which can house a volume of liquid. Generally, container 114 includes one or more walls which cooperate to contain a volume of liquid.
Referring to
Fluid cooler 100 in some alternative embodiments (not shown) does not include a lid 118. In one example, container 114 includes an opening 117 that remains uncovered during use. In another example, container 114 does not include opening 117 and is permanently sealed from the outside atmosphere.
Referring again to
In the example shown, fluid cooler 100 further includes a cooling liquid inlet 120 and a cooling liquid outlet 122. As shown, cooling liquid inlet 120 is fluidly coupled to a cooling liquid source 124. In some examples, cooling liquid source 124 is a municipal cold water supply line or any other source of cold liquid. In some cases, cooling liquid from cooling liquid source 124 has a temperature between 0° C. and 50° C.
As shown, fluid cooler 100 includes a cooling liquid conduit 126, and a cooling conduit 128. Cooling liquid conduit 126 is shown fluidly coupling cooling liquid inlet 120 and cooling liquid outlet 122. Cooling conduit 128 is shown fluidly coupling hot fluid inlet 104 and cooled liquid outlet 108.
During the use of at least one embodiment of fluid cooler 100, cooling liquid from cooling liquid source 124 enters fluid cooler 100 by cooling liquid inlet 120 and flows through cooling liquid conduit 126 to cooling liquid outlet 122. Similarly, hot fluid from hot fluid source 102 enters by hot fluid inlet 104, and flows through cooling conduit 128 in which the hot fluid is cooled (and condensed if the hot fluid is steam) to a cooled liquid which exits at cooled liquid outlet 108.
As shown, each of cooling liquid conduit 126, and cooling conduit 128 is at least partially submerged in liquid transfer medium 116. At least some of the cooling liquid flowing through cooling liquid conduit 126 provides a heat sink, which draws heat from the hot fluid inside cooling conduit 128. The heat from the cooling conduit 128 transfers through liquid transfer medium 116 and into cooling liquid conduit 126. In operation, the temperature of a given volume of hot fluid, inside cooling conduit 128, may fall as heat is lost to the cooling liquid inside of cooling liquid conduit 126. Where the hot fluid is steam, and the temperature falls below a threshold temperature, the steam changes phase to liquid condensate. The temperature of a given volume of the condensate, inside cooling conduit 128, may further fall as heat is lost from the condensate to the cooling liquid in cooling liquid conduit 126.
Generally, the rate of heat transfer from the hot fluid inside cooling conduit 128, to the cooling liquid inside cooling liquid conduit 126 depends on, among other things, the temperature difference between the cooling liquid and the hot fluid, and the physical properties of the conduits 126, 128 and the liquid transfer medium 116. Conduits 126 and 128 can be made of any suitable material. In some examples, conduits 126 and 128 are made of one or more of metals (e.g, copper, aluminum, or stainless steel), plastics, and ceramics (e.g. glass, or porcelain). Further, conduits 126 and 128 can have any suitable cross-sectional shape for transporting fluids, such as a circular, rectangular or triangular shape for example.
Liquid transfer medium 116 can be any suitable liquid. In some examples, liquid transfer medium 116 is potable water. Alternatively, liquid transfer medium 116 can be a gel, an oil, or any other suitable liquid having desired characteristics.
In the example shown, fluid cooler 100 includes a thermally sensitive flow regulator 130 operable to control the flow rate of cooling liquid through cooling liquid conduit 126 based on one or more of a temperature inside container 114, and a temperature of liquid transfer medium 116. This may permit an efficient control of cooling water usage, while preserving the performance of fluid cooler 100 (e.g. maintaining a discharge of cooled fluid at a temperature at or below a target temperature). In some examples, flow regulator 130 is at least partially submerged in liquid transfer medium 116 for responding to the temperature of liquid transfer medium 116. In at least one embodiment, flow regulator 130 includes a valve 130A operated by a thermally sensitive actuator 130B. The thermally sensitive actuator may gradually or stepwise move the valve between open and closed, or toggle the valve between open and closed, in response to a sensed fluid temperature (e.g. of the liquid transfer medium 116 in which it is at least partially submerged).
In at least one embodiment, fluid cooler 100 includes a cooling liquid discharge conduit 132 coupled to cooling liquid outlet 122. In the example shown, cooling liquid discharge conduit 132 directs cooling liquid from cooling liquid outlet 122 to a sink 134. In alternative embodiments, cooling liquid outlet 122 can direct cooling liquid to anywhere, such as a basin, a bottle, a floor drain, or onto the ground outside for example.
Fluid cooler 100, as shown, is configured to lessen the possibility of dirty cooled liquid contaminating cooling liquid source 124. As shown, cooled liquid conduit 110 is fluidly coupled to a drain for disposing of cooled liquid from hot fluid source 102 into the drain. Moreover, the conduits which transport dirty hot fluid and cooled liquid (hot fluid conduit 106, cooling conduit 128 and cooled liquid conduit 110) are shown fluidly isolated from the conduits which transport cooling liquid (e.g. potable water) from cooling liquid source 124 (cooling liquid conduit 126 and cooling liquid discharge conduit 132).
In the example shown, two conduit walls (e.g. of conduits 126 and 128) and liquid transfer medium 116 separates the dirty hot fluid and cooled liquid from the cooling liquid and liquid source 124. This may help reduce the possibility of the dirty hot fluid and cooled liquid from contaminating the cooling liquid source 124. For example, if cooling liquid conduit 126 were to rupture, then cooling liquid source 124 could become exposed to liquid transfer medium 116 (which may be potable water), but conduit 128 could continue to isolate the dirty hot fluid and cooled liquid therein from contaminating cooling liquid source 124. Similarly, if cooling conduit 128 were to rupture and contaminate liquid transfer medium 116, then cooling liquid conduit 126 could continue to isolate the cooling liquid source 124 from the contaminated liquid transfer medium 116.
As shown, cooling liquid discharge conduit 132 includes a free end 136 for discharging cooling liquid into sink 134. In the example shown, free end 136 is exposed to open air. This may lessen the possibility of drain 138 backing up and contaminating cooling liquid source 124 through free end 136. In some examples, there is a bracket 140 mountable to a tabletop 142 adjacent a sink, bottle, basin or other reservoir, for directing cooling liquid discharge conduit 132 into the sink, bottle, basin or other reservoir.
As shown, bracket 140 includes a first end 144, for penetrating a tabletop and having a first bore 146 for receiving cooling liquid discharge conduit 132. Bracket 140 is also shown including a second end 148 having a second bore 150 for receiving free end 136 of cooling liquid discharge conduit 132. In some examples, first end 144 includes any one or more retentive elements for securing to tabletop 142. In the example shown, first end 144 includes a cylindrical threaded portion 152 and a nut 154 which cooperate with a flange 156 to clamp bracket 140 onto tabletop 142. In alternative embodiments, the retentive element(s) of first end 144 includes one or more of snaps, magnets, thumbscrews, hooks, loops, straps, buckles, or any other suitable retentive element.
In at least some examples, first bore 146 and second bore 150 are substantially parallel. Cooling liquid discharge conduit 132, in some examples, extends through first and second bores 146 and 150, such that the direction of cooling liquid flow through first bore 146 (e.g. up) is approximately opposite to the direction of cooling liquid flow through second bore 150 (e.g. down).
In alternative embodiments (not shown), cooling liquid discharge conduit 132 is physically coupled to drain 138 by another backflow prevention device, such as a double check-valve, or a reduced pressure zone assembly.
In the example shown, cooled liquid conduit 110 includes a thermal shut-off valve 158. Thermal shut-off valve 158 closes conduit 110 to the flow of fluid in response to detecting a fluid temperature above a threshold. This may prevent fluid above a certain temperature from entering drain pipe 112, which might otherwise be a contravention of municipal law, safety standards or design parameters. Generally, a failure of fluid cooler 100 (e.g. container 114 leaks liquid transfer medium 116, flow regulator 130 malfunctions, or cooling liquid source 124 shuts off) can give rise to a discharge of fluid through cooled liquid conduit 110 above the threshold at which thermal shut-off valve 158 closes conduit 110. This may subsequently trigger an abnormal cycle fault condition in the hot fluid source 102, causing hot fluid source 102 to stop exhausting hot fluid.
Cooling liquid conduit 126 and cooling conduit 128 are shown extending within container 114. In the example shown, cooling liquid conduit 126 includes a coiled portion 160, and cooling conduit 128 includes a coiled portion 162. Coiled portions 160 and 162 may provide long path lengths and large surface areas for heat transfer to occur between cooling conduit 128 and cooling liquid conduit 126. However, in alternative examples, one or both of conduits 126 and 128 has a short path length and is free of coiled portions.
In at least some embodiments, coiled portions 160 and 162 are arranged in spaced relation within container 114, as shown by way of example in
Referring again to
In at least some embodiments, fluid cooler 100 includes a plurality of cooling liquid circuits (e.g. a second cooling liquid inlet, a second cooling liquid conduit, and a second cooling liquid outlet) each coupled to the same or different cooling liquid source(s). Similarly, in at least some embodiments, fluid cooler 100 includes a plurality of cooling circuits (e.g. a second hot fluid inlet, a second cooling conduit, and a second cooled liquid outlet) each coupled to the same or different hot fluid source(s) and drain pipe(s).
Reference is now made to
In at least some embodiments, one or more of conduits 126, 128 and 128b includes a coiled portion. In the example shown, cooling liquid conduit 126 includes coiled portion 160, cooling conduit 128 includes coiled portion 162, and second cooling conduit 128b includes a coiled portion 162b. Coiled portions 160, 162, and 162b may provide long path lengths and large surface areas for heat transfer to occur between cooling liquid conduit 126 and conduits 128 and 128b.
In some alternative embodiments, one or more of conduits 126, 128, and 128b follow a shaped path other than a coil to provide a long path length.
In some cases, the liquid transfer medium 116 present in the upper region of container 114, where coiled portion 160 of cooling liquid 126 extends past coiled portion(s) 162 (and 162b), has a lower temperature and therefore slightly higher density. This can cause the liquid transfer medium 116 in this upper region to flow by gravity downwardly. Similarly, in some cases the liquid transfer medium 116 present in the lower region, where coiled portion(s) 162 (and 162b) extends, has a higher temperature than the aforementioned upper region and therefore also a slightly lower density than the aforementioned upper region. This can cause the liquid transfer medium 116 in this lower region to flow upwardly by buoyancy.
An induced circulation, such as for example in the direction of arrow 170, may in some cases further enhance the transfer of heat from cooling conduit(s) 128 (and 128b) to cooling liquid conduit 126. In alternative embodiments, a fluid cooler or fluid cooler core does not include a structure which induces a flow of liquid transfer medium. In some examples (not shown), the coiled portion(s) 162 (and 162b) extends above the coiled portion 160, and/or the coiled portion 160 extends below the coiled portion(s) 162 (and 162b).
At 902, a flow of hot fluid (e.g. hot fluid discharged from hot fluid source 102) is directed through cooling conduit 128, which is at least partially submerged in liquid transfer medium 116 (e.g. potable water). In some examples, the flow of hot fluid is intended for a regulated drain (e.g. a municipal drain) into which hot fluid is prohibited. Accordingly, in some cases the flow of hot fluid can be cooled (and condensed if the hot fluid is steam) to a cooled liquid, and discharged into the drain (e.g. drain pipe 112) at a permissible temperature. In some embodiments, a second flow of hot fluid (e.g. discharged from a second hot fluid source 102b) is directed through a second cooling conduit 128b, which is at least partially submerged in liquid transfer medium 116.
At 904, a flow of cooling liquid (e.g. cold water) from cooling liquid source 124 (e.g. a municipal cold water supply line) is directed through cooling liquid conduit 126, which is at least partially submerged in liquid transfer medium 116. In at least some cases, the cooling liquid provides a heat sink to induce a transfer of heat from the flow of hot fluid in cooling conduit 128 across liquid transfer medium 116 to the cooling liquid inside cooling liquid conduit 126.
In some examples, the flow of cooling liquid is regulated by a thermally sensitive flow regulator 130 that is at least partially submerged in the liquid transfer medium 116. In some examples, the flow regulator 130 alters the flow rate of the cooling liquid in response to the temperature of the liquid transfer medium 116. In one example, when the temperature of the liquid transfer medium 116 falls, the flow regulator 130 reduces the flow rate of cooling liquid (e.g. by constricting the passage of cooling liquid through cooling liquid conduit 126), and when the temperature of the liquid transfer medium 116 again rises, the flow regulator 130 increases the flow rate of cooling liquid (e.g. by unconstricting the passage of cooling liquid through cooling liquid conduit 126).
At 906, the flow of hot fluid is cooled, by the loss of heat to liquid transfer medium 116 and cooling liquid inside cooling liquid conduit 126, into a flow of cooled liquid. In at least some cases, the temperature of the flow of cooled liquid is reduced to a temperature at which the cooled liquid is permitted (e.g. by law, safety standards, or design parameters) to be discharged into a drain (e.g. drain pipe 112). In some embodiments, the second flow of hot fluid is similarly cooled, by a loss of heat to liquid transfer medium 116 and cooling liquid inside cooling liquid conduit 126, into a second flow of cooled liquid.
At 908, the cooled liquid is discharged from the cooling conduit 128. In some cases, the cooled liquid is discharged directly into drain pipe 112. Alternatively, the cooled liquid is discharged into a storm drain, a floor drain, a basin or bottle.
At 910, the cooling liquid is discharged from cooling liquid conduit 126. In some cases, the cooling liquid is discharged directly into drain 138. Alternatively, the cooling liquid is discharged into a storm drain, a floor drain, a basin or a bottle. In some embodiments, the cooling liquid is discharged through open air into drain 138. This may prevent a backup of drain 138 from contaminating the cooling liquid source which is fluidly coupled to cooling liquid conduit 126 from which the cooling liquid is being discharged.
While the above description provides examples of the embodiments, it will be appreciated that some features and/or functions of the described embodiments are susceptible to modification without departing from the principles of operation of the described embodiments. Accordingly, what has been described above has been intended to be illustrative of the invention and non-limiting and it will be understood by persons skilled in the art that other variants and modifications may be made without departing from the scope of the invention as defined in the claims appended hereto. The scope of the claims should not be limited by the preferred embodiments and examples, but should be given the broadest interpretation consistent with the description as a whole.
Number | Date | Country | |
---|---|---|---|
61856337 | Jul 2013 | US |