Heat exchanger apparatus and methods for controlling the temperature of a high purity, re-circulating liquid
A heat exchanger apparatus enables the temperature of a liquid located external to the apparatus in a recirculation loop to be controlled by heat transfer within the apparatus. The apparatus has heat transfer tubes which may be helically wound around a fluid directional component. A manifold fitting is also provided for distributing fluid from multiple conduits to a single conduit.
This application is a continuation-in-part of U.S. patent application Ser. No. 10/889,779, filed Jul. 12, 2004 and titled HEAT EXCHANGER APPARATUS FOR A RECIRCULATION LOOP AND RELATED METHODS AND SYSTEMS, which is incorporated herein by reference.
TECHNICAL FIELDThe present invention relates generally to the field of cooling and heating fluids. More particularly, the present invention relates to cooling and heating fluids in fluid recirculation loops, such as those used in the manufacture of semiconductor wafers, which require the avoidance or at least minimization of impurities being introduced into the fluid in the recirculation loop.
BRIEF DESCRIPTION OF THE DRAWINGSUnderstanding that drawings depict only typical embodiments of the invention and are not therefore to be considered to be limiting of its scope, the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings. The drawings are listed below.
Elements shown in one or more of or discussed with reference to
10 process tank
20 recirculation pump
30 optional component
35 bypass line
60 controller
62 temperature sensor
70 compressed gas source
72 first valve for gas delivery
74 second valve for gas delivery
Elements shown in one or more of or discussed with reference to FIGS. 1, 2A-2C, 3a, 4A-4C, and 9A-9B, 10A-10B, 11A-11D, and 14:
100 heat exchanger apparatus
110 housing
112 shell
120 end cap
122 access portal
124 exhaust vent
130 end cap
132 inlet opening
134 outlet opening
140 heat transfer tubes
142i inlet ends of heat transfer tubes 140
142o outlet ends of heat transfer tubes 140
150 tube support combs
152 comb holes
160 baffle
162 baffle holes
164 baffle access
Elements shown in one or more of or discussed with reference to
200i inlet fitting
200o outlet fitting
204i anchorable inlet manifold fitting
204o anchorable outlet manifold fitting
205i connected inlet manifold fitting
205o connected outlet manifold fitting
206i extension of inlet manifold fitting
206o extension of outlet manifold fitting
210i inlet manifold fitting
210o outlet manifold fitting
212i first end of body 220i
212o first end of body 220o
214i second end of body 220i
214o second end of body 220o
216i passages
216o passages
217i terminal portion of passage 216i
218i face at the first end of body 220i
218o face at the first end of body 220o
220i body of inlet manifold fitting
220o body of outlet manifold fitting
222i seal interface of body 220i
222o seal interface of body 220o
224i track of body 220i
224o track of body 220o
226i groove of body 220i
226o groove of body 220o
240i manifold fitting receptacle
240o manifold fitting receptacle
242i threads of manifold fitting receptacle 240i
242o threads of manifold fitting receptacle 240o
244i sleeve portion of manifold fitting receptacle 240i
244o sleeve portion of manifold fitting receptacle 240o
250i fitting nut
250o fitting nut
252i threads of fitting nut 250i
252o threads (not shown) of fitting nut 250o
260i fluid communicator
260o fluid communicator
262i conduit of fluid communicator 260i
263i flared end of neck 264i of fluid communicator 260i
263o flared end of neck 264O of fluid communicator 260o
264i neck of fluid communicator 260i
264o neck of fluid communicator 260o
266i elbow of fluid communicator 260i
266o elbow of fluid communicator 260o
268i neck of fluid communicator 260i
268o neck of fluid communicator 260o
269i threads
260o threads
270i fitting nut
270o fitting nut
299 infrared heater
Elements shown in one or more of or discussed with reference to
300 gas separator case
302 exhaust end of gas separator case
304 delivery end of gas separator case
306 grooves
308 baffle rim of gas separator case 300
322 gas inlets
326 gas channels
328 gas channel extension
332 exhaust portal for gas separators 400c and 400h
334 delivery portals
342c access portal for gas separator 400c
342h access portal for gas separator 400c
360c cold gas stream chamber
360h hot gas stream chamber
370 delivery chamber
Elements shown in one or more of or discussed with reference to
400 hot gas passage
400c gas separator for delivery of stream of cold gas
400h gas separator for delivery of stream of hot gas
402 gas heater
403 inlet to the hot gas passage 400
405 channel of hot gas passage 400
406 outlet to the hot gas passage 400
410c flow restrictor for gas separator 400c
410h flow restrictor for gas separator 400h
412c slot
412h slot
420c hot gas separator
420h hot gas separator
422c vent holes
422h vent holes
424c bands
424h bands
426c vent holes
426h vent holes
430c stream decoupler
430h stream decoupler
440c expansion chamber
440h expansion chamber
450c vortex generator
450h vortex generator
452c slanted tunnels
452h slanted tunnels
453c interior surface or perimeter
453h interior surface or perimeter
460c cold gas discharge nozzle
460h cold gas discharge nozzle
470h cold gas separator of gas separator 400h
472h vent holes
490 annular grooves
492 O-rings
Elements shown in one or more of or discussed with reference to
600 coupling tube
670 fitting nut
1100 heat exchanger apparatus with a liquid passage component
1110 housing
1120 end cap
1122 inlet portal
1124 outlet portal
1130 end cap
1170i inlet fitting of the inlet portal
1170o outlet fitting of the outlet portal
1172i fitting nut of the inlet portal
1172o fitting nut of the outlet portal
1174i channel of the inlet fitting
1174o channel of the outlet fitting
1400 fluid passage component
1403 inlet of fluid passage component 1400
1405 channel of fluid passage component 1400
1406 outlet of fluid passage component 1400
1499 weir
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTSThe inventions described hereinafter relate to a recirculation loop heat exchanger apparatus and related methods and systems. The apparatus enables the temperature of a fluid source to be controlled by heat transfer across plastic tubes that isolate the fluid source from the cooling or heating fluid. The inventions also related to specific components as utilized with a recirculation loop heat exchanger apparatus or another apparatus.
A heat exchanger apparatus for a recirculation loop has many uses in cooling and/or heating a fluid. One example of such a use is in the manufacture of semiconductors wafers. Maintenance of the temperature of fluids used during the manufacture of semiconductor wafers is needed during many of the processing steps. Examples of such fluids used in the semiconductor manufacturing process include liquids used to etch, liquids used in photolithography processes, rinsing liquids, and cleaning fluids. Examples of etching liquids include hydrogen peroxide (H2O2) and acids such as hydrofluoric acid (HF) and hydrochloric acid (HCL). Examples of liquids used in photolithography processes include resist liquids and developer liquids. Slurry solutions and chemicals used in chemical-mechanical planarization (CMP) are also examples of processes that can be sensitive to small changes in temperature. Examples of rinsing liquids include deionized water and liquids used in the process known in semiconductor manufacturing industry as the RCA clean such as RCA rinsing liquids. Components used to contact such liquids are formed from materials which remain chemically inert to the liquid.
The heat exchanger apparatus has a small footprint which is ideal for use in the manufacture of semiconductor wafers. Due to the costs of facilities used in the manufacture of semiconductor wafers, it is beneficial to minimize the space required for all devices utilized in the manufacturing process.
In addition to controlling the temperature of the source liquid, the heat exchanger apparatus can be used to cool the source liquid from an elevated temperature in preparation for releasing into waste chemical lines. In many semiconductor fabrication facilities, waste line pipes cannot accept fluids warmer than about 50° C., due to the pipe material, and the chemically reactive characteristics of certain waste fluids. Accordingly, liquids, such as those mentioned above which are heated to e.g., 75° C., as is needed for efficient processing, cannot be released into waste lines, without first allowing them to cool down. Ordinarily, heated liquids are allowed to cool in a tank or reservoir within a processing unit. However, the processing unit is then not useable during the cool down interval. Consequently, manufacture of semiconductors is slowed. The heat exchanger apparatus allows this drawback to be minimized, by actively cooling the liquid, instead of storing the liquid in bulk and waiting for it to passively cool down in the tank. Specifically, the heat exchanger apparatus accelerates the rate of cooling and reduces the time required before the liquid source reaches a temperature acceptable for release into manufacturing facility waste lines. As a result, the processing unit is more readily available to process additional flat media.
In the embodiments disclosed herein of a heat exchange apparatus, a plurality of heat transfer tubes are helically wound around a fluid directional component for heat transfer. Various embodiments of a fluid directional component are disclosed including a fluid passage component, a temperature changing component, and a blocking component.
The fluid passage component and some embodiments of the temperature changing component are configured to block the flow of fluid through the center or main portion of the space defined by the heat transfer tubes while directing the flow of fluid across the tubes. Examples of a fluid passage component include tubular structures. The tubular structure may be utilized to transport a gas or a liquid. An example of a temperature changing component include at least one gas separator. Another example of a temperature changing component is an electrical gas heater.
The blocking component is positioned in the housing of the heat exchanger apparatus with the heat transfer tubes positioned around the blocking structure. The blocking component does not deliver a fluid but blocks its fluid flow through the center of the coils of the heat transfer tubes or main portion of the space defined by the heat transfer tubes. An embodiment of a heat exchange apparatus utilizing a blocking component, has fluid delivered directly into the housing so that the fluid flows substantially across the heat transfer tubes from one end of the housing to the other before exiting out of the housing. Examples of blocking components include closed and hollow structures and solid structures. In one embodiment, the blocking component is rod shaped. The blocking component may have any shape which is similar or identical to those of the exterior of the fluid passage components and the temperature changing components disclosed herein. The blocking component may have any shape which substantially blocks fluid flow through the center of the coils so that the fluid is directed substantially across the heat transfer tubes from one end of the housing to the other before exiting out of the housing.
The housing of the heat exchange apparatus, the fluid directional component and the heat transfer tubes enable heat to be transferred between two fluids as one of the fluids travels around in the coils of the heat transfer tubes and the other fluid travels in a path that is essentially transverse to the coils. The fluid directional component is configured to direct fluid such that the fluid does not pass through the center of coils and instead directs the fluid from one end of the housing of the heat exchanger apparatus to the other end and across the coils of the heat transfer tubes. For example, a fluid directional component which is a hollow tube or a gas separator receives the fluid and then directs the fluid into the space between the housing and the exterior of the fluid directional component.
Heat transfer tubes 140 are shown in the schematic diagrams of the methods and systems shown in and described with reference to
The fluid flow is forced across the bank of helical tubes between fluid directional component and shell 112. Flow is generally across tubes and not along the length of the tubes. Enhanced heat transfer is achieved due to mixing caused by flow through the tortuous path created by array of helical tubes.
A heat exchange apparatus which has heat transfer tubes helically positioned around a fluid directional component can be manufactured by various methods. For example, heat transfer tubes 140 can be manually positioned around a fluid directional component. The plurality of smaller diameter heat transfer tubes have a reduced bend radius before buckling would occur than a single larger tube with the same flow capacity. The smaller heat transfer tubes may be flexible so that they can be mechanically wound around a fluid directional component and avoid buckling due to their helical configuration within the housing of the heat exchange apparatus. Due to this flexibility, heat transfer tubes 140 may contact each other if support structures are not used to maintain transfer tubes in a particular spatial relationship. Support combs 150 are examples of support structures capable of maintaining heat transfer tubes 140 in their relative positions to other heat transfer tubes. Other support structures capable of maintaining heat transfer tubes 140 in relatively fixed positions may also be used.
In some embodiments, the heat transfer tubes are able to maintain their spatial relationship with respect to each other in between support structures and even avoid contacting each other. In other embodiments, the spatial relationship as defined by their relative positions in a support structure is maintained between two support structures in a configuration such that they do not contact each along the majority of the length between the two support structures. While the holes of the support combs are spaced apart to minimize contact between the tubes, the rigidity of the tubes also assists in their ability to avoid contacting each other as the rigidity enables the tubes to maintain their spatial relationship to adjacent tubes between support combs. When tubes are used with increased flexibility, then more support structures may be needed which are more closely positioned with respect to each other to prevent the tubes from contacting each other.
Any number of support structures such as combs 150 may be used such as one, two, three, four, five, six, etc. Also, any support structures may be used which are capable of holding the plurality of heat transfer tubes in a generally circular configuration. For example, support structures which hold each coil at three points maintains each coil in a generally circular configuration. In the embodiments depicted herein, three support combs 150 are used to maintain the coils of the plurality of heat transfer tubes in a generally circular configuration.
In one embodiment, three support combs are used and each comb has 28 holes per row and 6 holes per column and 12 heat transfer tubes are wound in these holes. The heat transfer tubes may be held in the holes of such an embodiment by threading several of the tubes into an interior row of each of the combs and followed by threading several other tubes into the next outer row. Note that for simplicity, not all of the coils which can be wound around a fluid directional component, are shown. For example, in one embodiment, the number of coils is 4 times greater than the number shown.
Comb 150 may, as shown, have holes in a column which are staggered with respect to the holes of an adjacent column and similarly the holes of a row may also be staggered with respect to the holes of an adjacent row. Some tubes 140 may be threaded such that the coils are not parallel and lean with slightly different orientations or with reverse orientations. The tubes positioned in outer rows may have a substantially reverse helix angle with respect to tubes positioned in inner rows.
By positioning coils of heat transfer tubes such that spirals with greater diameters are positioned around coils with smaller diameters, heat transfer tubes can have long lengths while being wrapped around a fluid directional component which is much shorter. For example, in one embodiment, the length of the fluid directional component, may be about 12 inches. In one embodiment, the length of the heat transfer tubes relative to the length of the fluid directional component is about 3:1 to about 100:1. In other embodiments, it ranges from about 5:1 to about 30:1, 10:1 to about 20:1, and 12:1 to about 15:1. Heat transfer tubes 140 may all have the same length or tubes used in a single apparatus may have different lengths.
The volume of the heat tubes relative to the volume defined by the exterior of the fluid directional component and the housing of the heat exchange apparatus may range from about 5% to about 75% in one embodiment. The space between the housing the fluid directional component is also referred to as the plenum. In other embodiments, the volume of the heat tubes relative to the volume of the plenum may range from about 10% to about 60%, from about 15% to about 50%, from about 25% to about 45%, from about 30% to about 40%, and about 35%.
Liquid from process tank 10 flows to heat transfer tubes 140 or other heat transfer tubes via recirculation pump 20 which pressurizes the liquid. The process liquid may optionally return from heat transfer tubes 140 after passing through an optional component 30 such as a flow meter, filter, valve, etc. Liquid may also be routed through a bypass line 35 for high flow to optional component 30 from the line or the fluid communicator which delivers the pressurized liquid to heat transfer tubes 140. Alternatively, the liquid may return from the heat transfer tubes 140 to feed into the recirculating process between the process tank 10 and the recirculation pump 20. This enables high fluid flow though the bypass line 35 to be recirculated back to the liquid source. The liquid flowing through the heat exchanger apparatus mixes with the liquid flowing to the recirculation pump. The liquid source temperature can be altered and controlled by controlling the heat transferred to the liquid flow through the heat exchanger apparatus and mixing of the two liquid flows in the recirculation loop.
The temperature of process tank 10, the source of the liquid, is monitored and controlled via a controller 60 which is electronically coupled to a temperature sensor 62. Temperature sensor 62 is positioned to determine the temperature of the liquid in the process tank.
Compressed gas, such as nitrogen or air, is delivered to gas separator 400c and gas separator 400h in housing 110 of heat exchanger apparatus 100 from compressed gas source 70. First valve 72 controls gas delivery to gas separator 400c. Second valve 74 controls gas delivery to gas separator 400h. The compressed gas may be supplied to the gas separator at a flow rate of about 10 to about 35 standard cubic feet per minute (SCFM) and at a pressure of about 50 to 100 psig. For manufacturing semiconductor wafers, the compressed gas is typically supplied to the gas separator at a flow rate of about 15 SCFM and at a pressure of about 80 psig.
Apparatus 100 may be utilized to maintain a liquid in a process tank at room temperature (approximately 22° C.). For such a use, apparatus 100 may be designed to adjust the temperature of the process tank or ambient bath by ±5° C. to maintain it at approximately 22° C. Apparatus 100 may also be utilized to heat or cool the liquid beyond ambient temperature. The gas streams or fractions generated by the gas separators may have temperatures ranging from about −40° C. to about 110° C. The cold gas stream generated by the gas separator may have a temperature ranging from about 28° C. to about 50° C. below the temperature of the pressurized gas received by the gas separator. The amount of heat transferred by apparatus 100 varies depending on the design. For example, it may be designed to transfer about 75 to about 300 watts. It may be designed to transfer about 120 watts for typical uses in the manufacture of semiconductor wafers.
Inlet manifold fitting 210i and outlet manifold fitting 210o are shown extending through end cap 130. Inlet manifold fitting 210i and outlet manifold fitting 210o are respectively positioned within manifold fitting receptacle 240i and manifold fitting receptacle 240o.
Each manifold fitting has a body. Body 220i of inlet manifold fitting 210i and body 220o of outlet manifold fitting 210o are formed from a plastic material as described in more detail below. Body 220i of inlet manifold fitting 210i and body 220o of outlet manifold fitting 210o respectively hold the inlet ends 142i and outlet ends 142o of heat transfer tubes 140. This configuration permits each manifold fitting to be coupled with a single fluid communicator having only one conduit such as a tube or a bulkhead.
The clustering of the plurality of heat transfer tubes 140 at their ends enables a large volume of flowing fluid to be delivered from and returned to process tank 10 or another source of fluid and to then be separated into much smaller flowing volumes within housing 110 of apparatus 100. Separating the fluid into smaller flowing volumes within the separate tubes of the plurality of heat transfer tubes 140 provides for more efficient heat exchange. Tubes 140 have a large surface area, a relatively thin wall thickness, and a relatively small inner diameter. These factors enhance the ability of the fluid in tubes 140 to be heated or cooled by fluid contacting the outside of the tubes 140.
As mentioned above, the configuration of the manifold fittings permits the opposing ends of the plurality of heat transfer tubes 140 to be collectively coupled with a single fluid communicator having only one conduit such as a tube. Fluid communicator 260i and fluid communicator 260o are examples of such fluid communicators having only a single conduit. The fluid communicator may have more than one conduit. However, it is beneficial for the single conduit or multiple conduits to have a diameter or perimeter that is larger than the inner diameter or inner perimeter of tubes 240. Conduit 262i of fluid communicator 260i is shown in
The embodiments of fluid communicators depicted in
Pressurized gas is introduced into gas separator case 300 by a compressed gas line (not shown) and into gas inlets 322c and 322h shown in
As discussed in more detail with respect to
When gas separator 400c delivers a relatively cooler gas stream or gas separator 400h delivers a relatively hotter gas stream into the space defined by housing 110 for heat transfer with the fluid in tubes 140, the gas stream is delivered at delivery end 304 of gas separator case via delivery portals 334. The other stream of gas vented by gas separator 400c (relatively hotter than the pressurized gas) or by gas separator 400h (relatively cooler than the pressurized gas), the bypass gas stream, is directed out of housing 100 in manner which limits its contact with the plurality of heat transfer tubes or other heat transfer tubes. Such a gas stream is directly vented via exhaust portal 332 out of gas separator case 300. As best seen in
Exhaust vent 124, shown in
The heat exchange gas stream passes through baffle holes 162 of baffle 160 before exiting via exhaust vent 124, as best understood in reference to
Gas separators 400c and 400h each include a flow restrictor 410, a hot gas separator 420, a stream decoupler 430, an expansion chamber 440, a vortex generator 450, and a cold gas discharge nozzle 460. Gas separator 400h also includes a cold gas separator 470h.
The compressed gas is introduced directly into vortex generator 450 via gas channel 320. Vortex generator 450 forces the pressurized gas to rotate and thereby create a vortex from the pressurized gas. As seen in
The vortex is forced down the expansion chamber 440 towards the stream decoupler 430. The vortex travels down expansion chamber 440 along the inside perimeter of the chamber. Although the expansion chamber shown in the accompanying drawings is tapered such that its interior diameter increases as it approaches the stream decoupler 430, other embodiments are possible. For instance, the expansion chamber could have a uniform interior diameter or, alternatively, its interior diameter could decrease as it approaches the stream decoupler. Although stream decoupler 430 need not be present in all embodiments of gas separators, it has been found that, under certain conditions, it may be useful to include a stream decoupler to straighten out the vortex somewhat prior to venting the hot gas stream through the hot gas separator 420. Stream decoupler 430 has an opening with a plurality of projections or vanes 432, as best seen in
After passing through stream decoupler 430, the now hot gas at the perimeter of the interior bore of the gas separator is vented by hot gas separator 420. Although they serve essentially the same purpose, it can be seen from the accompanying figures that hot gas separator 420h differs structurally from hot gas separator 420c. It should be understood, however, that some embodiments of the invention may have two gas separators, each of which have components which are identical.
Hot gas separator 420h has a plurality of vent holes 422h. The hot gas stream is vented through the hot gas separator 420h and then out through vent holes 422h. As is discussed in greater detail below, the amount of hot gas that is allowed to vent through vent holes 422h may be controlled by controlling how far flow restrictor 410h is threaded into hot gas separator 420h.
Hot gas separator 420c instead directs the hot gas through vent holes 422c that lead back towards the center of the device and outside of the interior bore. Optionally, one or more bands 424 may be disposed around the perimeter of the region to which the hot gas is directed, as shown in the accompanying figures. These bands 424 may also have vent holes 426c that are coaxial with vent holes 422c. Bands 424 may be used to provide support for a gas permeable muffling cover (not shown). Such a cover may be comprised of any suitable material which allows gas to permeate there through and may be tightly fit over bands 424 in order to reduce the noise associated with venting the hot gas.
After the hot gas stream is vented from the gas separator, the remaining gas stream is reflected off of flow restrictor 410 and travels down the center of the gas separator in the opposite direction. Flow restrictor 410 may be adjustable so as to allow the temperature and volume of the cold and hot streams of gas to be varied. In the depicted embodiment, adjustment of flow restrictor 410 may be made by screwing and unscrewing the flow restrictor 410. For example, a screwdriver may be inserted via access portal 122 of housing 100 and access portal 342c of gas separator case 300 into slot 412c. As the flow restrictor 410 is unscrewed, or threaded away from the hot gas separator 420, a greater portion of hot gas is released from the hot gas separator 420. This likewise affects the volume and temperature of cold gas released from the opposite side of the gas separator. Note that, as shown in
As it travels down the center of the gas separator, the gas transfers heat to the gas spiraling in the other direction along the interior perimeter of the gas separator and is thereby cooled. In the depicted embodiment, the cold gas is vented through cold gas discharge nozzle 460. Cold gas discharge nozzle 460 may optionally be adapted to be fit with a vent tube to direct the cold gas to a desired location. In the depicted embodiment, cold gas discharge nozzle 460c sends the cold gas stream down a portion of gas separator case 300, including the cold gas stream chamber 360c and delivery chamber 370, and out one or more delivery portals 334 in case 300, which allows the gas stream to contact the heat transfer tubes 140. Note that delivery chamber 370 also receives hot gas from hot gas stream chamber 360h as the hot gas proceeds out of delivery portals 334.
A gas permeable muffler (not shown) may be located in the vent tube. For example, a muffler may comprise a plastic material, such as a woven polypropylene around hot gas separator 420c or an open cell foam in delivery chamber 370. Such a device may be comprised of any suitable material which allows gas to permeate there through and reduce the noise associated with venting the cold gas.
Gas separator 400h has an additional component-cold gas separator 470h—which is connected with cold gas discharge nozzle 460h. Cold gas separator 470h has vent holes 472h, which direct a cold gas stream out of the heat exchanger apparatus 100 via exhaust vent 124. Like hot gas separator 420c, cold gas separator 470h may have one or more bands 474h, and may also be fit with a gas permeable muffling cover (not shown) similar to that described above in connection with the hot gas separator 420c.
In embodiments of the invention including two gas separators, such as the embodiment shown in
Of course, embodiments of the invention having only a single gas separator are also envisioned as described in reference to
Many of the fundamental aspects of the gas separators are well-known to those of skill in the art, as demonstrated by U.S. Pat. No. 3,173,273 issued to Fulton; U.S. Pat. No. 4,240,261 issued to Inglis; U.S. Pat. No. 5,558,069 issued to Stay; U.S. Pat. No. 5,682,749 issued to Bristow et al.; and U.S. Pat. No. 6,032,724 issued to Hatta. All of the foregoing references are hereby incorporated by reference in their entirety.
Gas separators 400 may be fit within gas separator case 300, which may be configured to receive one or more gas separators. Gas separators 400 or, more particularly, one or more gas separator components, may also be configured with annular grooves 490. Each annular groove 490 may then be fit with in O-ring 492. Use of O-rings allows for creation of one or more seals to direct the gas to desired locations and/or prevent the passage of gas to undesired locations.
The objective of heating tubes 140 and the portion of body 220i below face 218i is to form a fluid-tight seal between the outer diameter of tubes 140 and body 220i so when fluid is transferred from a fluid communicator all of the fluid flows into tubes 140 and not around tubes 140 into passages 216i. When heat is applied, the circular tubes expand and engage the passages 216i. When the materials reach their melting point temperatures, the tubes 140 and body 220i fuse together at heated face 218i and directly below the heated face 218i. Such results are achieved primarily through the use of plastics which are either identical or are sufficiently compatible to have similar melting temperatures. Other variables include the duration of the exposure to the heating source, the temperature of the heating source, the proximity of the heat source to face 218i, and the wall thickness of tubes 140.
The bodies of the manifold fittings and tubes 140 may be formed from any plastic material which remains inert to fluids such as hydrofluoric acid and other liquids used in manufacturing semiconductor wafers. Fluoropolymers are examples of suitable plastics. Specific examples of fluoropolymers which remain inert during exposure to various fluids include: polytetrafluoroethylene (PTFE) sold as Teflon, fluorinated ethylene propylene (FEP), polyperfluoroalkoxyethylene (PFA) and polyvinyl difluoride (PVDF). Other plastics which may be utilized include polypropylene (PP), polyvinyl chloride (PVC), and polyvinyl difluoride (PVDF). The other components of heat exchanger apparatus 100 may also be formed from such plastics.
The plastic components are heated at or above their melting points to fuse portions of the tubes within the passages of the body of manifold fitting to the upper portion of the body of manifold fitting. Utilizing plastics which are identical or relatively similar enables the plastic components to simultaneously reach their melting points or reach them at very similar temperatures. Proper selection of such plastics ensures that one component does not receive excessive heat once it reaches its melting point as the other component is still approaching its melting point. Avoidance of excessive heating assists in preserving the geometrical shape of the inner diameter of the tubes. Deformation of the tubes from their original geometry during heating could prevent a fluid from freely flowing through the tubes.
The longer that the components are exposed to the heat then the deeper the penetration of the heat. The weld depth may be twice the thickness of the wall of the tubes to ensure that there is a secure seal. As mentioned above, the walls of tubes 140 are selected to be sufficiently thin to permit rapid and efficient heat transfer. The wall thickness is also selected to be sufficiently thick to withstand the pressure of the pressurized liquid and to prevent weeping of the fluid. For example, when the fluid is hydrofluoric acid (HF) pressurized to about 45 psi, the tube may have a wall thickness ranging from about 0.01 inches to about 0.02 inches. More particularly, a tube formed for such use from polyperfluoroalkoxyethylene may have a wall thickness of about 0.02 inches. To fuse such tubes to the body of a manifold fitting, an infrared heater is set at a temperature of 600° F. and positioned about 0.5 inch away from the face of the body of the manifold fitting and the inlet ends of the tubes for about 1 minute.
The embodiment of heat exchanger apparatus 100′ shown in
Like the embodiment of the heat exchanger apparatus having two gas separators, a heat exchanger apparatus having a single gas separators controls the delivery of the gas stream contacting the plurality of heat transfer tubes by: selectively enabling the gas to flow into the gas separator, selectively adjusting the pressure of the gas flowing into the gas separator, selectively adjusting the gas separator to alter the ratio of a cold or hot gas stream.
As best seen in
Gas heater 402 is in fluid communication with hot gas passage 400. In the embodiment shown in
As described above, the plurality of heat transfer tubes 140 are adapted to contain a fluid and are helically wound around and along at least the majority of the length of a fluid directional component such as fluid passage component 1400 or a temperature changing component such as case 300 of gas separators or a heater. Housing 100, the fluid directional component and heat transfer tubes 140 enable heat to be transferred between the two fluids as one of the fluids travels around in the coils of the heat transfer tubes and the other fluid travels from the inlet of the fluid directional component to the outlet of the fluid directional component. The fluid passing across heat transfer tubes 140 in housing 110 travels in a direction which is essentially parallel with an axis of housing 110 or fluid directional component and essentially transverse with respect to the coils of heat transfer tubes 140.
The embodiment shown in
The other components in
The heat transfer tubes disclosed herein are examples of heat transfer components. The heat transfer tubes are also examples of heat transfer means for receiving a pressurized fluid in the housing for heat transfer as delivered from a fluid source, providing sufficient surface area for effective heat and transfer and for delivering the fluid out of the housing to be routed back to the fluid source.
The support combs are examples of support structures. Support structures are examples of means for spatially orienting the heat transfer means for effective heat transfer. The baffle is an example of means for directing the heat transfer gas stream across the heat transfer means, for minimizing contact with the heat transfer means from the bypass gas stream as the bypass gas stream is directed out of an exhaust vent, and for directing the heat transfer gas stream out of the exhaust vent after the heat transfer gas stream has contacted the heat transfer means.
As indicated above, a gas separator is an example of a temperature changing component. The gas separators are also examples of temperature changing means for receiving pressurized gas, for separating the pressurized gas into a high temperature stream and a low temperature stream relative to the temperature of the pressurized gas received, for directing one of the gas streams into contact with the plurality of heat transfer components and then out of the housing, and for directing the other stream out of the housing while limiting the contact with the heat transfer means. Such temperature changing means are also examples of means for cooling or heating the fluid in the heat transfer means. Other examples of means for heating or cooling the fluid in the heat transfer means include a hot bath or cold bath through which the heat transfer means passes.
Another example of a temperature changing component is a gas heater. Some embodiments of gas heaters are examples of temperature changing means for receiving a pressurized gas, heating the gas and directing the gas into contact with the plurality of heat transfer components. The gas heaters are also examples of means for heating the fluid in the heat transfer means.
The temperature changing components are examples of fluid delivery components. Other examples of fluid delivery components include fluid passage components. Examples of fluid passages components include tubular structures. Temperature changing components and fluid passage components are examples of fluid delivery components as they are able to receive a fluid and then direct the fluid into the space between the housing and the exterior of the fluid delivery component. The fluid delivery components are examples of means for receiving a fluid into the housing and delivering the fluid into contact with the plurality of heat transfer tubes.
The fluid delivery components are also fluid directional components. Other examples of fluid directional components include blocking components. In contrast to fluid delivery components, a blocking component does not deliver a fluid is just blocks its flow through the center of the coils. An embodiment utilizing a closed, hollow, rod-shaped structure positioned along the center axis of the housing of the heat exchanger apparatus to act as a blocking component, has fluid delivered directly into the housing so that the fluid flows substantially across the heat transfer tubes from one end of the housing to the other before exiting out of the housing.
A fluid directional component is positioned in the housing of the heat exchanger apparatus with the heat transfer tubes positioned around the blocking component to block the flow of fluid through the center or main portion of the space defined by the heat transfer tubes. Whether the fluid directional component is hollow like a fluid passage component, contains various structural components such as a gas separator, or is a solid blocking component, these embodiments of the fluid directional component direct fluid substantially across the coils from one end of the housing of the heat exchanger apparatus to the other end while minimizing or preventing flow through the center of the coils of the heat transfer tubes. The fluid delivery components positioned within the coils and the blocking components are examples of means for directing the fluid across the coils and minimizing or preventing flow through the center of the coils of the heat transfer tubes.
The inlet manifold fittings are examples of inlet manifold means for providing fluid communication between the plurality of heat transfer means and an inlet fluid communicator having a conduit in fluid communication with the fluid source to enable the plurality of heat transfer means to receive the pressurized fluid in the housing from the fluid source. The outlet manifold fittings are examples of outlet manifold means for providing fluid communication between the plurality of heat transfer means and an outlet fluid communicator having a conduit in fluid communication with the fluid source to enable the plurality of heat transfer means to deliver the pressurized fluid out of the housing to the fluid source.
All of the heat exchanger apparatus components, except the electrical heating element and associated control devices as described previously, can be constructed of non metallic materials enabling the apparatus to be exposed to the process liquids without adversely changing the operation of the heat exchanger apparatus.
Without further elaboration, it is believed that one skilled in the art can use the preceding description to utilize the invention to its fullest extent. The examples and embodiments disclosed herein are to be construed as merely illustrative and not a limitation of the scope of the present invention in any way. It will be apparent to those having skill in the art that changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. In other words, various modifications and improvements of the embodiments specifically disclosed in the description above are within the scope of the appended claims. Note that elements recited in means-plus-function format are intended to be construed in accordance with 35 U.S.C. § 112 ¶6. The scope of the invention is therefore defined by the following claims.
Claims
1. A method to alter and control the temperature of a process liquid, without adversely affecting the quality thereof, comprising:
- sensing the temperature of the process liquid,
- controlling the delivery of a pressurized gas from a source of pressurized gas,
- changing the temperature of the pressurized gas,
- delivering the gas, after its temperature has been changed, to contact at least one plastic heat transfer tube, and
- circulating a liquid from a source of liquid such that the liquid flows and is in contact with the heat transfer tube to enable the heat transfer tube to heat or cool the liquid contacting the heat transfer tube to control the temperature of the liquid in the source.
2. The method of claim 1, further comprising monitoring the temperature of the source of liquid to enable the delivery of the pressurized gas to be controlled based on input received regarding the temperature of the source of liquid.
3. The method of claim 1, wherein the delivery of the pressurized gas is controlled by selectively delivering the pressurized gas.
4. The method of claim 1, wherein the delivery of the pressurized gas is controlled by selectively adjusting the pressure of the pressurized gas.
5. The method of claim 1, wherein the temperature of the pressurized gas is changed before it is delivered to the heat transfer tube as the pressurized gas passes through one of at least two temperature changing components.
6. The method of claim 5, wherein the two temperature changing components are selectively utilized to deliver pressurized gas to the heat transfer component.
7. The method of claim 1, wherein the temperature of the pressurized gas is changed by heating the pressurized gas.
8. The method of claim 1, wherein the temperature of the pressurized gas is changed by separating the pressurized gas into a high temperature stream and a low temperature stream relative to the temperature of the pressurized gas before separation and wherein at least one of the gas streams is then delivered to the heat transfer tube.
9. The method of claim 8, wherein the ratio of the high temperature stream and the low temperature stream is selectively adjustable.
10. The method of claim 1, wherein the pressurized gas is delivered, after its temperature has been changed, to a plurality of heat transfer tubes.
11. The method of claim 10, wherein each of the heat transfer tubes has an inlet to receive the pressurized gas and an outlet for delivery of the pressurized gas.
12. The method of claim 10, wherein each of the heat transfer tubes is a tube having an inlet end, wherein the inlet ends are positioned in a body of an inlet manifold fitting, wherein the outlet ends are positioned in the body of an outlet manifold fitting, wherein the inlet manifold fitting is adapted to be coupled with a single fluid communicator having only one conduit.
13. The method of claim 10, wherein each of the heat transfer tubes has a wall thickness which permits the pressurized gas to be contained by each tube while transferring heat to the liquid from a higher temperature gas or from the liquid to a lower temperature gas.
14. The method of claim 1, wherein the heat transfer tube is chemically inert to any liquid contacting the heat transfer tube.
15. The method of claim 1, wherein the temperature of the liquid in the source of liquid is maintained via the method in a range from 0° C. to 120° C.
16. An apparatus for transferring heat to a process fluid, without adversely affecting the quality thereof, the apparatus comprising:
- a housing having a first end and a second end,
- a fluid directional component situated longitudinally within the housing,
- a plurality of plastic heat transfer tubes adapted to contain a first fluid, wherein the plurality of heat transfer tubes are within the housing and are outside of the fluid directional component,
- wherein each of the heat transfer tubes has an inlet to receive the first fluid from a source outside of the housing and an outlet to deliver the first fluid out of the housing, wherein one end of each of the heat transfer tubes is fused into a fluid manifold fitting;
- wherein the housing, the fluid directional component and the heat transfer tubes enable heat to be transferred between the first fluid and a second fluid as the first fluid travels in the heat transfer tubes and the second fluid travels in contact with the exterior of the heat transfer tubes around the fluid directional component and within the housing.
17. The apparatus of claim 16, wherein the ends of the plurality of heat transfer tubes fused into a fluid manifold fitting are adapted to be in fluid communication with a single fluid communicator.
18. The apparatus of claim 16, wherein said fluid manifold fitting and the ends of the plurality of heat transfer tubes have been fused together by placing the heat transfer tubes in holes in a manifold body, configuring the ends of the heat transfer tubes to be substantially flush to a face of the manifold body, and applying sufficient radiant heat to said tube ends to cause their outer walls to expand against and fuse with the walls of the holes in the manifold body to form a seal between the tubes and the manifold body.
19. The apparatus of claim 16, wherein the apparatus is configured such that the first fluid is isolated to be within the inside of the heat transfer tubes and the fluid manifold fitting and another fluid manifold fitting.
20. An apparatus for transferring heat to a process fluid, without adversely affecting the quality thereof, the apparatus comprising:
- a housing having a first end and a second end,
- a fluid directional component within the housing,
- a plurality of plastic heat transfer tubes adapted to contain a first fluid, wherein the plurality of heat transfer tubes are within the housing and are helically wound around the fluid directional component such that there are coils of heat transfer tubes along at least a portion of the length of the fluid directional component,
- wherein each of the heat transfer tubes has an inlet to receive the first fluid from a source outside of the housing and an outlet to deliver the first fluid out of the housing, and
- wherein the housing, the fluid directional component and the heat transfer tubes enable heat to be transferred between the first fluid and a second fluid as the first fluid travels around in the coils of the heat transfer tubes and the second fluid travels in contact with the exterior of the heat transfer tubes around the fluid directional component and within the housing.
21. The apparatus of claim 20, wherein the inlets of the heat transfer tubes are adapted to collectively receive the first fluid from a single fluid communicator.
22. The apparatus of claim 20, wherein the outlets of the heat transfer tubes are adapted to collectively deliver the first fluid to a single fluid communicator.
23. The apparatus of claim 20, wherein the coils have a plurality of diameters such that some coils are different distances from the exterior of the fluid directional component.
24. The apparatus of claim 20, wherein the coils are wrapped around each other in an offset configuration.
25. The apparatus of claim 20, wherein the heat transfer tubes are flexible enough to avoid buckling due to their helical configuration within the housing.
26. The apparatus of claim 20, wherein the apparatus further comprises a plurality of tube support combs positioned within the housing, wherein the tube support combs have a plurality of holes and the tubes are positioned in the holes to enable the second fluid to flow around the tubes.
27. The apparatus of claim 20, wherein the holes are spaced apart to minimize contact between the tubes.
28. The apparatus of claim 20, wherein the plurality of heat transfer tubes are held with at least three points in each coil to maintain each coil in a generally circular configuration.
29. The apparatus of claim 20, wherein the apparatus has a length of about 12 inches.
30. The apparatus of claim 20, wherein the ratio of the length of the tubes to the length of the housing ranges from about 3:1 to about 100:1.
31. The apparatus of claim 20, wherein the volume of the space in the housing around the tubes ranges from about 5% to about 75% of the total volume between the housing and the fluid directional component.
32. The apparatus of claim 20, wherein the heat transfer tubes are chemically inert.
33. The apparatus of claim 20, wherein the fluid directional component is a temperature changing component.
34. The apparatus of claim 20, wherein the fluid directional component is a fluid passage component.
35. The apparatus of claim 20, wherein the fluid directional component is a blocking component.
36. The apparatus of claim 20, further comprising a baffle positioned in the housing.
37. An apparatus for transferring heat to a process fluid, without adversely affecting the quality thereof, the apparatus comprising:
- a housing having a first end and a second end,
- a gas delivery component within the housing, wherein the gas delivery component has an at least one inlet to receive a fluid and an outlet to deliver the gas into the housing,
- a plurality of heat transfer tubes adapted to contain a liquid, wherein the plurality of heat transfer tubes are within the housing and are helically wound around the gas delivery component along at least a portion of the length of the gas delivery component, wherein each of the heat transfer tubes has an inlet to receive a liquid from a source outside of the housing and an outlet to deliver the liquid out of the housing, and
- wherein the housing and the gas delivery component enable gas to be delivered in the housing to contact the plurality of heat transfer tubes and then to pass out of the housing.
38. An apparatus for transferring heat to a process fluid, without adversely affecting the quality thereof, the apparatus comprising:
- a housing having a first end and a second end,
- at least one temperature changing component positioned in the housing, wherein the temperature changing component has an inlet to receive pressurized fluid and an outlet to deliver the fluid into the housing, and wherein the temperature changing component changes the temperature of the fluid before the fluid is delivered into the housing,
- a plurality of heat transfer tubes adapted to contain a liquid, wherein the plurality of heat transfer tubes are within the housing and are helically wound around at least a portion of the length of the temperature changing component, wherein each of the heat transfer tubes has an inlet to receive a liquid from a source outside of the housing and an outlet to deliver the liquid back to the source to control the temperature of the liquid in the source, and
- wherein the housing and the temperature changing component direct the fluid in the housing into contact with the plurality of heat transfer tubes and then out of the housing.
39. A system for transferring heat to a process liquid, without adversely affecting the quality thereof, the system comprising:
- a fluid temperature changing apparatus comprising
- a case having an inlet and an outlet, and
- at least one temperature changing component within the case, wherein temperature changing component receives pressurized gas via the inlet and then changes the temperature of gas before it is delivered to the outlet; and
- a heat exchange apparatus comprising
- a housing,
- a fluid passage component within the housing, wherein the fluid passage component has an inlet to receive a fluid and an outlet to deliver the fluid out of the fluid passage component and into the housing, and
- a plurality of heat transfer tubes adapted to receive the gas from the temperature changing component, wherein the plurality of heat transfer tubes are within the housing and are helically wound around the fluid passage component such that there are coils of heat transfer tubes along at least the majority of the length of the fluid passage component, and
- wherein the housing, the fluid passage component and the heat transfer tubes enable heat to be transferred between the gas and the fluid as the gas travels around in the coils of the heat transfer tubes and the liquid contacts the heat transfer tubes as the liquid travels from the inlet of the fluid passage component to the outlet of the passage component.
40. A system for transferring heat to a process fluid, without adversely affecting the quality thereof, the system comprising:
- a fluid temperature changing apparatus comprising
- a case having at least one inlet and two outlets, and
- at least one gas separator positioned within the case, wherein the gas separator receives pressurized gas via the inlet and then separates the pressurized gas into a high temperature stream and a low temperature stream relative to the temperature of the pressurized gas received by the gas separator, wherein the gas separator is adapted to separately direct the gas streams out of the case via the outlets
- a heat exchange apparatus comprising
- a housing,
- at least one heat transfer tubes adapted to receive one of the gas streams from the gas separator, wherein the heat transfer tube is positioned around a liquid passage component and within the housing, and wherein the housing, the liquid passage component and the heat transfer tubes enable heat to be transferred between the gas and the liquid as the gas travels through the heat transfer tube and the liquid contacts the heat transfer tube as the liquid flows from the liquid passage component and within the housing.
41. A system for transferring heat to a process fluid, without adversely affecting the quality thereof, the system comprising:
- a controller;
- a fluid temperature changing apparatus comprising at least one gas separator, wherein the gas separator receives pressurized gas and then separates the pressurized gas into a high temperature stream and a low temperature stream relative to the temperature of the pressurized gas received by the gas separator,
- a heat exchange apparatus comprising
- at least one heat transfer tube adapted to receive one of the gas streams from the gas separator, wherein the heat transfer tube is positioned in the flow of the process liquid in a liquid passage component, and wherein the heat transfer tube enables heat to be transferred between the gas and the liquid as the gas travels through the heat transfer tubes and the liquid contacts the heat transfer tube.
Type: Application
Filed: May 2, 2005
Publication Date: Jan 12, 2006
Inventor: Troy Orr (Draper, UT)
Application Number: 11/120,028
International Classification: F28F 13/06 (20060101);