US20170299230A1

US20170299230A1 - Thermodynamic management for integrated densified fluid-based textile treatment

Info

Publication number: US20170299230A1
Application number: US15/445,172
Authority: US
Inventors: Chris Robbins; Dave Sauder; Steve Madsen
Original assignee: CO2Nexus Inc
Current assignee: Tersus Solutions LLC; CO2Nexus Inc
Priority date: 2016-03-08
Filing date: 2017-02-28
Publication date: 2017-10-19
Also published as: WO2017155751A1

Abstract

A direct contact densified fluid-based thermodynamic treatment system uses the fluid to effect heat transfer as the working fluid in a separate yet linked treatment system. During certain phases of operation of a densified fluid-based treatment process wherein it is necessary to distill the fluid to maintain the purity of the densified fluid heat is imparted to the densified fluid raising it above the boiling point for the associated pressure within a vessel. A densified fluid-based refrigeration/thermodynamic system removes heat during the condensing cycle of a working densified fluid treatment system and use the removed heat for distillation of the same working fluid in the distillation vessel. The process does not require an external heating or cooling system, and thus can be entirely supported by a single machine using the same densified fluid during its operational phase.

Description

RELATED APPLICATION

The present application relates to and claims the benefit of priority to U.S. Provisional Patent Application No. 62/305,069 filed 8 Mar. 2016 which is hereby incorporated by reference in its entirety for all purposes as if fully set forth herein.

BACKGROUND OF THE INVENTION

Field of the Invention

Embodiments of the present invention relate, in general, to thermodynamic management systems and more particularly to thermodynamic management of CO2-based article treatment.

Relevant Background

In general, thermodynamic systems are those that affect some sort of energy conversion or transfer. In power-generation systems the interest lies in the conversion of internal energy of hydrocarbon fuel molecules or atomic energy of uranium or plutonium into mechanical energy that is ultimately converted into electrical energy. In refrigeration systems keeping an area cool by removing energy in the form of heat is the focus. These systems involve a heat transfer fluid such as water or air or refrigerant, which is, in the case of power generation, circulated through the system in a cycle.
In steam power plants and refrigeration systems the cycle is closed while in other thermodynamic systems, such as a jet engine, the cycle is open. Many refrigeration systems utilize a vapor-compression cycle. In such a cycle, a circulating refrigerant enters a compressor as a vapor. The vapor is compressed at constant entropy (isentropic and adiabatic) so as to exit as a vapor at a higher temperature. This superheated vapor is then passed through a condenser where it cools (gives off heat) until the vapor condenses into a liquid by removing heat at a constant pressure forming a saturated liquid. Pressure is decreased through a controlled expansion device resulting in a mixture of vapor and liquid at a significantly lower temperature. This vapor and liquid mixture then passes through an evaporator where the fluid is heated by passing it through warm air. Or said differently warm air is cooled by transferring the heat from the air to the vapor and liquid mixture until the refrigerant is entirely a vapor. At that point the refrigerant vapor returns to the compressor completing the cycle. As one of reasonable skill in the relevant art will appreciate there are many forms of refrigeration cycles. These can include vapor absorption cycle or a gas cycle in which the working fluid does not change phase.
The ability to transfer heat in such a closed process depends, in a large part, by the working fluid, that is, the refrigerant. Different refrigerants have different enthalpy values for a given state. When dealing with one specific refrigerant the enthalpy values depend on the temperatures and pressures in the warm and cold regions of the cycle. Moreover the surrounding temperature affects how well the refrigeration system is able to cool an enclosed region.
In each case the refrigerant, as the fluid used for heat transfer, is different than that of the working fluid or medium that it affects. For example in the case of refrigeration systems, refrigerant or other like material, is used to reduce the air temperature of a space. The refrigerant fluid remains in a closed system while the target environment remains open. As can be appreciated this adds complexity and cost but it is impractical to close the working environment. For example we need to access the contents of a refrigerator or freezer and a building that is air-conditioned cannot exist as a closed system. However some systems that utilize external heating and cooling systems are essentially closed systems as well.
One such system is a CO2-based treatment system. Mechanisms specific to one CO₂process employ dense phase CO₂as the principal treatment/rinsing agent including a high-pressure gaseous rinse cycle in essentially a closed system. The CO₂treatment methodology includes an enhanced rinsing and distillation process that is enabled by a proper thermodynamic balance (heat transfer via an external refrigeration system). Such a system is designed with sufficient storage capacity to enable continuous, real time distillation of CO₂to separate contaminants producing pure, uncontaminated CO₂throughout wash & rinse cycle(s).
The current CO2 treatment system however relies on an external heat transfer system to maintain a densified CO2. And while the accomplishments of such a treatment system are by themselves noteworthy the added complexity and cost of an external heat transfer systems are problematic.
A need therefore exists to craft a pseudo-closed system that utilizes the same fluid both as a means to transfer heat and as the working fluid for the environment in which it operates. The present invention addresses these and other deficiencies of the prior art.
Additional advantages and novel features of this invention shall be set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the following specification or may be learned by the practice of the invention. The advantages of the invention may be realized and attained by means of the instrumentalities, combinations, compositions, and methods particularly pointed out in the appended claims.

SUMMARY OF THE INVENTION

A system and associated methodology for thermodynamic management of a densified fluid treatment system uses direct contact between the working densified fluid of the treatment system and densified fluid refrigerant of the heart management system. According to one embodiment of the present invention, a densified fluid treatment system includes a treatment system having a densified fluid, a distillation vessel, a storage vessel closeably connected to the distillation vessel, a treatment vessel for treatment of an article with the densified fluid at a hyper-atmospheric pressure in which the treatment vessel is connected to the storage vessel, and a fluid displacement device, connected to and interposed between the treatment vessel and the distillation vessel. The fluid displacement device (pump) is operable to transfer the densified fluid throughout the treatment system in a liquid state and/or in a vapor state, and compress the vapor state of the densified fluid into the liquid state of the densified fluid. In addition the distillation vessel continuously cleans the densified fluid used to treat the article.
The densified fluid treatment system of the present invention further includes a heat management system that includes the densified fluid, a compressor, a distillation vessel heat exchanger connected to the compressor by a distillation heat supply line, a storage vessel heat exchanger connected to the compressor by a compressor fill line wherein interposed between the storage vessel heat exchanger and the compressor is a compressor fill line heat exchanger. The heat management system also includes an expansion a valve interposed between the distillation vessel heat exchanger and the storage vessel heat exchanger that is connected to the distillation vessel heat exchanger by a distillation heat return line and connected to the storage vessel heat exchanger by a storage fill line.
Lastly the densified fluid treatment system, according to one embodiment of the present invention includes a charge line closeably connecting the storage vessel of the treatment system to the compressor fill line to maintain volumetric content of the densified fluid within the heat management system. Additional features of the invention described above include wherein the compressor fill line heat exchanger is a plurality of heat exchangers configured in series or in parallel. In addition, the compressor fill line heat exchanger can be an adiabatic heat exchanger and is operable to add heat to the heat management system. Likewise, a bypass heat exchanger can be a plurality of heat exchangers configured in series or parallel and can be connected to the distillation heat supply line and the distillation heat return line to manage heat within the heat management system. In one embodiment of the present invention the bypass heat exchanger removes heat from the heat management system.
In other embodiments the compressor is a super critical adiabatic compressor while in yet another embodiment the distillation vessel heat exchanger resides within the distillation vessel. Similarly the storage vessel heat exchanger can reside within the storage vessel. While many different types of densified fluid can be used by the present invention and are indeed contemplated, a principal densified fluid is carbon dioxide.
A method for heat management in a densified fluid treatment system, according to another embodiment of the present invention begins with combining the densified fluid treatment system with a heat management system in which the densified fluid treatment system and the heat management are fluidly coupled using a common densified fluid. The process continues by managing heat exchange within the densified fluid treatment system by the heat management system using the densified fluid of the densified fluid treatment system.
Additional features of the method described above, according to the present invention include maintaining the densified fluid within the heat management system with densified fluid from the densified fluid treatment system. As with the previously described embodiment the densified treatment system includes the commonly used densified fluid, a distillation vessel, a storage vessel closeably connected to the distillation vessel, a treatment vessel for treatment an article with the densified fluid at a hyper-atmospheric pressure wherein the treatment vessel is connected to the storage vessel, and a fluid displacement device, connected to the treatment vessel and the distillation vessel, operable to transfer the densified fluid throughout the treatment system in a liquid state and in a vapor state. Moreover the fluid displacement device can compress the vapor state of the densified fluid into the liquid state of the densified fluid and wherein the distillation vessel continuously cleans the densified fluid treatment the article.
The method for heat management in a densified fluid treatment system uses, according to one embodiment a heat management system that includes the densified fluid, a compressor, a distillation vessel heat exchanger connected to the compressor by a distillation heat supply line, a storage vessel heat exchanger connected to the compressor by a compressor fill line wherein interposed between the storage vessel heat exchanger and the compressor is a compressor fill line heat exchanger, an expansion a valve interposed between the distillation vessel heat exchanger and the storage vessel heat exchanger and connected to the distillation vessel heat exchanger by a distillation heat return line and connected to the storage vessel heat exchanger by a storage fill line.
An additional step in the method for heat management using densified fluid for the treatment of articles, according to one embodiment of the methodology describe above, includes connecting the storage vessel to the compressor fill line by a charge line so as to maintain volumetric content of the densified fluid within the heat management system.
Another embodiment of a densified fluid treatment system includes a hyper-atmospheric treatment system having a densified fluid, a treatment vessel, a storage vessel, and a distillation vessel wherein the densified fluid is continuously cleaned within the distillation vessel during a treatment cycle. This treatment system is used in connection with a heat management system that includes a heat transfer fluid and a plurality of heat exchangers, wherein one or more of the plurality of heat exchangers resides within each the distillation vessel and the storage vessel and wherein the heat transfer fluid is the same densified fluid used in the hyper-atmospheric treatment system.
The features and advantages described in this disclosure and in the following detailed description are not all-inclusive. Many additional features and advantages will be apparent to one of ordinary skill in the relevant art in view of the drawings, specification, and claims hereof. Moreover, it should be noted that the language used in the specification has been principally selected for readability and instructional purposes and may not have been selected to delineate or circumscribe the inventive subject matter; reference to the claims is necessary to determine such inventive subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

The aforementioned and other features and objects of the present invention and the manner of attaining them will become more apparent, and the invention itself will be best understood, by reference to the following description of one or more embodiments taken in conjunction with the accompanying drawings, wherein:

FIG. 1 presents a high level view of a densified fluid-based treatment system as would be known to one skilled in the relevant art;

FIG. 2 shows, according to one embodiment of the present invention, a high-level block diagram of a closed loop densified fluid-based treatment system using a CO2 refrigerant system;

FIG. 3 presents a high level block diagram of one embodiment of the present invention of a densified fluid article treatment system with a contiguous (connected fluid) heating and cooling configuration;

FIGS. 4A and 4B present a thermodynamic conversion chart for CO2 as applied to one embodiment of the present invention; and

FIG. 5 is a flowchart of one method embodiment of a process for heat management of a densified fluid treatment system.

The Figures depict embodiments of the present invention for purposes of illustration only. One skilled in the art will readily recognize from the following discussion that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the invention described herein.

DESCRIPTION OF THE INVENTION

A direct contact densified fluid-based thermodynamic treatment system is disclosed in which the fluid used to effect heat transfer is also the working fluid of a separate treatment system. During certain phases of operation of a densified fluid-based treatment process, it is necessary to distill the fluid to maintain the purity of the densified fluid. This process requires a means impart heat to the densified fluid raising it above the boiling point for the associated pressure within a vessel. This heat normally comes from an external heat source (electric, steam, and the like). It then subsequently requires a heat rejection source to remove the latent heat to condense the densified fluid vapor back to liquid for use in the subsequent treatment cycle. This is again normally accomplished by an external cooling system (chill water, refrigeration unit, condensing system). Accordingly, the heat added to affect one aspect of the system has to be subsequently removed in the next.
One embodiment of the present invention uses a densified fluid-based refrigeration/thermodynamic system to remove heat during the condensing cycle of a working densified fluid treatment system and use the removed heat for distillation of the same working fluid in the distillation vessel. The process of the present invention does not require an external heating or cooling system, and thus can be entirely supported by a single machine using the same densified fluid during its operational phase. During non-operational periods such as the pressure-maintaining phase of the system, the heat that is removed from the storage vessel is rejected to the ambient atmosphere.
Embodiments of the present invention are hereafter described in detail with reference to the accompanying Figures. Although the invention has been described and illustrated with a certain degree of particularity, it is understood that the present disclosure has been made only by way of example and that numerous changes in the combination and arrangement of parts can be resorted to by those skilled in the art without departing from the spirit and scope of the invention.
The following description with reference to the accompanying drawings is provided to assist in a comprehensive understanding of exemplary embodiments of the present invention as defined by the claims and their equivalents. It includes various specific details to assist in that understanding but these are to be regarded as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention. Also, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.
By the term “substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those of skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.
Like numbers refer to like elements throughout. In the figures, the sizes of certain lines, layers, components, elements or features may be exaggerated for clarity.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Thus, for example, reference to “a component surface” includes reference to one or more of such surfaces.
As used herein any reference to “one embodiment” or “an embodiment” means that a particular element, feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment.
As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having” or any other variation thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Further, unless expressly stated to the contrary, “or” refers to an inclusive or and not to an exclusive or. For example, a condition A or B is satisfied by any one of the following: A is true (or present) and B is false (or not present), A is false (or not present) and B is true (or present), and both A and B are true (or present).
The term “distillation” is a widely used method for separating mixtures based on differences in the conditions required to change the phase of components of the mixture. To separate a mixture of liquids, the liquid can be heated to force components, which have different boiling points, into the gas phase. Simple distillation can be used when the boiling points of two liquids are significantly different from each other or to separate liquids from solids or nonvolatile components. In simple distillation, a mixture, in this case CO2, is heated to change the most CO2 component from a liquid into vapor. The vapor rises and passes into a condenser. Usually, the condenser is cooled to promote condensation of the vapor, which is collected as a pure form of CO2.
A “heat exchanger” is a device used to transfer heat between a solid object and a fluid, or, between two or more fluids. There are three primary classifications of heat exchangers according to their flow arrangement. In parallel-flow heat exchangers, two fluids enter the exchanger at the same end, and travel in parallel to one another to the other side. In counter-flow heat exchangers the fluids enter the exchanger from opposite ends. The counter current design is the most efficient, in that it can transfer the most heat from the heat (transfer) medium per unit mass due to the fact that the average temperature difference along any unit length is higher. In a cross-flow heat exchanger, the fluids travel roughly perpendicular to one another through the exchanger.
A materials “heat capacity” or “thermal capacity”, C, is the amount of heat required to change its temperature by one degree. It is the ratio of heat energy transferred to an object to the resulting increase in temperature. Therefore a substance's heat capacity is a measure of its ability to carry heat. For example air has a low heat capacity while water is reasonably high.
“Adiabatic” is understood to refer to a process that occurs without transfer of heat or matter between a thermodynamic system and its surroundings. In an adiabatic process, energy is transferred only as work and not as heat. For example, the compression of a gas within a cylinder of an engine is assumed to occur so rapidly that on the time scale of the compression process, little of the system's energy can be transferred out as heat to the surroundings. Even though the cylinders are not insulated and are quite conductive, that process is idealized to be adiabatic. The same can be said to be true for the expansion process of such a system. Adiabatic heating occurs when the pressure of a gas is increased from work done on it by its surroundings, e.g., a piston compressing a gas contained within an adiabatic cylinder. This finds practical application in diesel engines which rely on the lack of quick heat dissipation during their compression stroke to elevate the fuel vapor temperature sufficiently to ignite it. Adiabatic cooling occurs when the pressure on an adiabatically isolated system is decreased, allowing it to expand, thus causing it to do work on its surroundings. When the pressure applied on a parcel of air is reduced, the air in the parcel is allowed to expand; as the volume increases, the temperature falls as its internal energy decreases.
“Densified” is a past tense participle of the word densify, meaning to make more dense or compress. A densified fluid is a fluid under sufficient pressure such that the fluid exists in a supercritical state. A supercritical fluid is one which the temperature and the pressure of the fluid are above its critical point where distinct liquid and gas phases do not exist. Supercritical fluids can effuse through solids like a gas and dissolve materials like a liquid.
The present invention involves the use of densified fluids or substances in a supercritical state. In most instances the pressure required to establish such a state is significantly greater than atmospheric pressure. Atmospheric pressure relates to the pressure of the atmosphere at sea level. “Hyper-Atmospheric” pressure is therefore pressure in excess (significantly greater) of atmospheric pressure. Standard atmospheric pressure for 1 atmosphere (1 atm) is 29.92 inHG or 14.696 psi. By comparison hyper-atmospheric pressure required to place CO2 in a supercritical state is 72.9 atm or 1071 psi.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein. Well-known functions or constructions may not be described in detail for brevity and/or clarity.
It will be also understood that when an element is referred to as being “on,” “attached” to, “connected” to, “coupled” with, “contacting”, “mounted” etc., another element, it can be directly on, attached to, connected to, coupled with or contacting the other element or intervening elements may also be present. In contrast, when an element is referred to as being, for example, “directly on,” “directly attached” to, “directly connected” to, “directly coupled” with or “directly contacting” another element, there are no intervening elements present. It will also be appreciated by those of skill in the art that references to a structure or feature that is disposed “adjacent” another feature may have portions that overlap or underlie the adjacent feature.
Spatially relative terms, such as “under,” “below,” “lower,” “over,” “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of a device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is inverted, elements described as “under” or “beneath” other elements or features would then be oriented “over” the other elements or features. Thus, the exemplary term “under” can encompass both an orientation of “over” and “under”. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. Similarly, the terms “upwardly,” “downwardly,” “vertical,” “horizontal” and the like are used herein for the purpose of explanation only unless specifically indicated otherwise.
Currently CO2-based treatment systems require a distiller to purify the CO2 used in the treatment process. As mentioned, to do so heat must be added to the CO2 to distill the fluid. FIG. 1 presents a high level view of a CO2-based treatment system as would be known to one of reasonable skill in the relevant art. In such a treatment system one or more articles to be cleaned are placed in a treatment vessel (150) that uses, in this example, a densified fluid, such as densified CO2, to remove particulates and contaminants. As one of reasonable skill in the relevant art can appreciate fluid exiting the treatment vessel carries with it contaminants and unwanted materials from the articles. By way of reference, liquid CO2 is a natural solvent to many petroleum based products. Articles that are soiled by oil and similar substances can be effectively treated and cleaned through emersion and agitation with liquid CO2. Upon contact with the soiled articles the liquid CO2 carries with it impurities originating in the articles. That fluid is thereafter purified in a distillation vessel 120 and then returned via a pump 115 to a storage vessel 110 for reuse within the treatment vessel 150.
A distillation process within the distillation vessel 120 is used to purify the CO2. Used CO2 enters the distillation vessel 120 and is subjected to heat from a distillation vessel heat exchanger 130. The CO2 vaporizes releasing contaminants. The purified vapor is passed to a second heat exchanger 140 that removes the heat added in the distillation process enabling the CO2 vapor to condense. Once cooled and returned to a liquid state the now purified CO2 is retained in a storage vessel 110 for later use within the treatment vessel 150.
The overall CO2 treatment system is a closed system. That is, the fluid used to clean the articles is recycled, contiguously purified and used again. Ideally no new CO2 needs to be added or used CO2 removed from the system.
The heat added to the distillation process is delivered via a typical boiler 135. In many instances heat is added to a heat transfer fluid (refrigerant) such as water forming steam and passed to a distillation vessel heat exchanger 130. The heat from the steam transfers to the liquid CO2 causing the CO2 liquid to vaporize and the steam to condense. The condensate (water) is pumped via a condensate pump 138 back to the boiler where the cycle begins anew. One of reasonable skill in the relevant art will appreciate other heat transfer fluids can be used as can multiple heat exchanger designs.
The second heat exchanger 140, shown in FIG. 1 operates similarly to remove heat from the purified CO2 working fluid. To effect the treatment process the purified CO2 vapor needs to be condensed to its liquid form. To do so heat, added during the purification/distillation process, must be removed. One skilled in the art can appreciate that the adding and subsequent removal of heat to CO2 by two separate independent systems is not necessarily an efficient thermodynamic process.
One embodiment of the present system uses the heat released from the condensation of the CO2 vapor as it enters the clean CO2 storage vessel 110 to heat (vaporize) the contaminated CO2 entering the distillation vessel 120, using the CO2 working fluid as the heat transfer fluid or refrigerant. FIG. 2 shows, according to one embodiment of the present invention, a high-level block diagram of a densified fluid based treatment system using the densified treatment fluid as refrigerant in the heating/cooling system.
A densified fluid treatment system includes a treatment vessel 150 interposed between a distillation vessel 120 and a densified fluid storage vessel 110. In line between the treatment vessel 150 and the distillation vessel 120 is a liquid pump/vapor compressor 115 to effect movement of the densified fluid throughout the treatment system.
The present invention shown in FIG. 2, in one embodiment, includes a closed densified fluid heat pump system to control the heat and state of a common densified fluid-based article treatment system. In another embodiment of the present invention the common densified fluid can be R744 (CO2) As with the systems previously described, heat is added to the distillation vessel 120 to purify the densified fluid used in the treatment process within the treatment vessel 150. The vaporized, and therefore purified, densified fluid is thereafter returned to the clean densified fluid storage vessel 110 via densified fluid return line 215. In the embodiment of the present invention shown in FIG. 2 a clean densified fluid storage vessel heat exchanger 280 is attached to, or resides within the clean densified fluid storage vessel 110, and removes heat from the purified densified fluid and conveys it to the distillation vessel heat exchanger 130, via a compressor fill line 275 and the distillation heat supply line 295, residing within, or attached to, the distillation vessel 120. The densified fluid heating process however must be managed, as the heat removed from the clean densified fluid storage vessel 110 may be insufficient to meet the needs of the densified fluid purification process taking place in the distillation vessel 120.
One aspect addressed by the present invention is the need to compress the heat transfer fluid within the heat management system to a supercritical pressure and temperature using a super critical adiabatic compressor 220. The heated densified fluid or refrigerant is introduced into the distillation vessel 120 through the distillation heat supply line 295 via a distillation vessel heat exchanger 130. In the present invention the heat is managed using additional heat exchangers 210, 260 in series or parallel. Thus in some instances (as described below) additional heat can be added using one or more additional adiabatic compressor fill line heat exchangers 260 (arranged in series or parallel between the storage vessel heat exchanger 280 and the super critical compressor 220) or removed using one or more bypass heat exchangers 210. In one version of the invention a bypass heat exchanger 210 is an air/heat exchanger (arranged in series or parallel between the distillation heat return line 235 and the distillation heat supply line 295). By doing so a precise amount of heat in a closed system can be maintained. One of reasonable skill in the relevant art will recognize that the number and configuration of heat exchangers can be adjusted as necessary. And when the treatment system is non-operational the bypass heat exchanger(s) 210 can be used to manage the heat in the heat management system.
Another function of the additional adiabatic compressor fill line heat exchanger(s) 260 is to ensure that the state of the densified fluid being introduced to the super critical compressor 220 is gas and not fluid. Accordingly if the densified fluid in the heat management system coming out of the clean densified fluid storage vessel 110 is liquid or a liquid/vapor combination, additional heat can be added at the compressor fill line heat exchanger(s) 260 to make sure that the densified fluid is a vapor state when reaching the super critical compressor 220. Note that the compressor fill line heat exchanger is coupled with the compressor fill line 275 and the distillation heat return line 235.
Fluid coming from the distillation vessel heat exchanger 130 in the distillation vessel 120 and traveling to the clean densified fluid storage vessel 110 via the distillation heat return line 235 passes through the compressor fill line heat exchanger 260 and goes through a trans-critical expansion valve 250. This expansion valve 250 enables one side of the densified fluid to be above the critical temperature and pressure and the other side to be below the densified fluid critical temperature and pressure. This expansion value 250 is, in one embodiment, a single stage system as opposed to a super critical stage and a subcritical stage to drop pressure.
The working heat transfer densified fluid of heat management system of the present invention is the same densified fluid used to clean articles in the densified fluid article treatment system. When additional fluid is needed within the heat management system, clean densified fluid from the clean densified fluid storage vessel 110 can be added to the heat management system via a supplemental make-up or charge line 272. The fluid interaction between treatment system and the heat management system is bridged by charge line valve 270 placed on the charge line 272. Thus as the heat transfer densified fluid or refrigerant is depleted the present invention can maintain the content of the heat management system with the densified fluid used within the treatment system.
Another embodiment of the present systems forms an “open” treatment/heat management system in which the heat management system using the common densified fluid and the article treatment system are contiguous. Note that the combined densified treatment system and heat management system remains closed with respect to the surrounding environment but the interaction of the heat transfer portion of the treatment process is characteristically open. FIG. 3 presents a high level block diagram of one embodiment of the present invention of a CO2 article treatment system with a contiguous heating and cooling system.
FIG. 3 presents a densified fluid-based heat management system for a densified fluid treatment process in which cold purified densified fluid used within the heat management system is directly introduced 310 to the clean densified fluid storage vessel 110 to control the temperature and pressure of the clean densified fluid storage vessel 110. As with the system described above, the densified fluid used in the heat management process is the same fluid used in the densified fluid-based article treatment process. As pure densified fluid leaves the distillation vessel 120, heat can be added back into or removed from the distillation process using one or more bypass heat exchanger(s) 210.
Heat is exchanged efficiently to maintain the working conditions of the storage vessel 110. In this example, the clean densified fluid storage vessel heat exchanger 280 of the prior embodiment is replaced by a direct contact mixing system 310 in which the cooled densified fluid coming from the trans-critical expansion valve 250 is released directly into the clean densified fluid storage vessel 110 to control temperature. As with the prior design one or more compressor fill line heat exchangers 260 are connected to the densified fluid return line at a juncture 320 between the compressor fill line 385 and the densified fluid return line.
FIGS. 4A and 4B present a thermodynamic conversion chart and associated thermodynamic schematic for CO2 as applied to the embodiment of the present invention shown in FIG. 3 in which the exchange of heat within the clean densified fluid storage vessel 110 is via a direct contact mixing system 310. One aspect of the present invention is that by controlling the transfer of heat during the distillation process the amount of densified CO2 transferred between the distillation vessel 120 and the clean densified fluid storage vessel 110 can be effectively managed.
FIG. 4B is a thermodynamic heat transfer schematic of a CO2 fluid-based heat management system for a CO2 fluid treatment process in which cold purified densified CO2 used within the heat management system is directly introduced 310 to the clean densified fluid storage vessel 110 to control the temperature and pressure of the clean densified fluid storage vessel 110. One of reasonable skill in the relevant art will appreciate that the schematic shown in FIGS. 4A and 4B represent the transfer of heat not fluid.
In this embodiment of the present invention in reference to FIG. 4B an adiabatic compressor fill line heat exchanger 260 is fluidly coupled to the heat management system and the article treatment system at juncture 320. Proceeding clockwise from the compressor fill line heat exchanger 260 at point 1 the heat within the fluid passes through an adiabatic compressor 220 at point 2 to arrive at the distillation vessel heat exchanger 130 at point 3. Note that the distillation vessel heat exchanger 130 resides within the distillation vessel 120 (not shown). From that point heat within the fluid moves back towards the compressor fill line heat exchanger 260 via a bypass heat exchanger 210 that can add or subtract heat as necessary. In the depiction shown in FIG. 4B the bypass heat exchanger 210 is shown in line with the distillation vessel heat exchanger 130. One of reasonable skill in the relevant art will appreciate that the depiction of arrangement of the bypass heat exchanger in FIG. 4B merely shows the addition/subtraction of heat and not the physical configuration of the device. Indeed the bypass heat exchanger 210 can be configured so as to be in parallel or in series with the distillation vessel heat exchanger 130.
As the heat within the fluid passes through the bypass heat exchanger 210 toward the compressor fill line heat exchanger 260 it is directed to an expansion value 250 at point 5 and eventually to the direct contact mixing system 310 within the clean densified fluid storage vessel 120 at point 6. The compressor fill line heat exchanger 260 acts as a heat management system with respect to heat transferred from the heat management system to the treatment system. From the compressor fill line heat exchanger 260 the fluid may return to the heat management system or be used within the article treatment system as necessary. Heat within the heat management system is transferred to the treatment system by way of the distillation vessel heat exchanger 130 within the distillation vessel 120. The now cooler densified fluid in the heat management system interacts with heated vapor from the distillation vessel 120 to remove the heat and aid in condensation. Additional heat is released by the direct contact mixing system 310 within the clean densified fluid storage vessel 110 at point 6.
FIG. 4A presents the same representation of the flow of heat illustrating an internal heat transfer process by the compressor fill line heat exchanger 260 at point 1. Heat added to the densified fluid as part of the distillation process is extracted within the compressor fill line heat exchanger 260 and the direct contact mixing system 310 and added to the heat transfer fluid within the heat management system. At points 2 and 3 of FIG. 4A heat is imparted from the heat management system to the article treatment system. The imparted heat is returned to the heat management system at point 1 before the fluid reaches the expansion value 250 at point 6 and finally the direct contact mixing system 310 at point 6.
The present invention presents a system wherein the densified fluid used as a refrigerant is the same as the working fluid in a densified fluid treatment system. The refrigerant, according to one embodiment of the present invention, is used to cool and heat densified fluid and indeed the same densified fluid is supplied from a common reservoir. The present treatment system uses densified fluid (in one embodiment CO2) to remove contaminants and particulate from various articles and to manage heat transfer during the treatment process. The present invention removes the need for an external heating and cooling system by using the working fluid as the refrigerant and working fluid. This results an energy savings in excess of 30% over conventional systems.
Included in the description are flowcharts depicting examples of the methodology which may be used manage heat in a densified fluid treatment system. In the following description, it will be understood that each block of the flowchart illustrations, and combinations of blocks in the flowchart illustrations, can be implemented by computer program instructions. These computer program instructions may be loaded onto a computer or other programmable apparatus to produce a machine such that the instructions that execute on the computer or other programmable apparatus create means for implementing the functions specified in the flowchart block or blocks. These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable apparatus to function in a particular manner such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means that implement the function specified in the flowchart block or blocks. The computer program instructions may also be loaded onto a computer or other programmable apparatus to cause a series of operational steps to be performed in the computer or on the other programmable apparatus to produce a computer implemented process such that the instructions that execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart block or blocks.
Accordingly, blocks of the flowchart illustrations support combinations of means for performing the specified functions and combinations of steps for performing the specified functions. It will also be understood that each block of the flowchart illustrations, and combinations of blocks in the flowchart illustrations, can be implemented by special purpose hardware-based computer systems that perform the specified functions or steps, or combinations of special purpose hardware and computer instructions.
FIG. 5 is a flowchart of one method embodiment of a process for heat management of a densified fluid treatment system. The process begins 505 with combining 510 and fluidly connecting a densified fluid treatment system with a heat management system. The two systems are fluidly coupled 540 using a common densified fluid such that the working fluid of the densified fluid treatment system and the refrigerant of the heat management system are the same fluid and the systems are congruent.
With the two systems fluidly coupled, the process manages 580 heat exchanges between the densified fluid treatment system and the heat management system using the common densified fluid. One of reasonable skill in the relevant art will appreciate that the proposed combination of a densified fluid treatment system and heat management system may not be 100% efficient. Indeed supplement sources of heat may be added (or heat removed) to the densified fluid via the bypass heat exchangers. Nonetheless, the present invention enables the densified fluid treatment system and the heat management system use the same densified fluid to not only treat the articles of interest but to manage heat requirements as the fluid is continuously distilled and condensed to maintain its purity.
Some portions of this specification are presented in terms of algorithms or symbolic representations of operations on data stored as bits or binary digital signals within a machine memory (e.g., a computer memory). These algorithms or symbolic representations are examples of techniques used by those of ordinary skill in the data processing arts to convey the substance of their work to others skilled in the art. As used herein, an “algorithm” is a self-consistent sequence of operations or similar processing leading to a desired result. In this context, algorithms and operations involve the manipulation of information elements. Typically, but not necessarily, such elements may take the form of electrical, magnetic, or optical signals capable of being stored, accessed, transferred, combined, compared, or otherwise manipulated by a machine. It is convenient at times, principally for reasons of common usage, to refer to such signals using words such as “data,” “content,” “bits,” “values,” “elements,” “symbols,” “characters,” “terms,” “numbers,” “numerals,” “words”, or the like. These specific words, however, are merely convenient labels and are to be associated with appropriate information elements.
Unless specifically stated otherwise, discussions herein using words such as “processing,” “computing,” “calculating,” “determining,” “presenting,” “displaying,” or the like may refer to actions or processes of a machine (e.g., a computer) that manipulates or transforms data represented as physical (e.g., electronic, magnetic, or optical) quantities within one or more memories (e.g., volatile memory, non-volatile memory, or a combination thereof), registers, or other machine components that receive, store, transmit, or display information.
It will also be understood by those familiar with the art, that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Likewise, the particular naming and division of the modules, managers, functions, systems, engines, layers, features, attributes, methodologies, and other aspects are not mandatory or significant, and the mechanisms that implement the invention or its features may have different names, divisions, and/or formats. Furthermore, as will be apparent to one of ordinary skill in the relevant art, the modules, managers, functions, systems, engines, layers, features, attributes, methodologies, and other aspects of the invention can be implemented as software, hardware, firmware, or any combination of the three. Of course, wherever a component of the present invention is implemented as software, the component can be implemented as a script, as a standalone program, as part of a larger program, as a plurality of separate scripts and/or programs, as a statically or dynamically linked library, as a kernel loadable module, as a device driver, and/or in every and any other way known now or in the future to those of skill in the art of computer programming. Additionally, the present invention is in no way limited to implementation in any specific programming language, or for any specific operating system or environment. Accordingly, the disclosure of the present invention is intended to be illustrative, but not limiting, of the scope of the invention, which is set forth in the following claims.
In a preferred embodiment, portions of the present invention can be implemented in software. Software programming code which embodies the present invention is typically accessed by a microprocessor from long-term, persistent storage media of some type, such as a flash drive or hard drive. The software programming code may be embodied on any of a variety of known media for use with a data processing system, such as a diskette, hard drive, CD-ROM, or the like. The code may be distributed on such media, or may be distributed from the memory or storage of one computer system over a network of some type to other computer systems for use by such other systems. Alternatively, the programming code may be embodied in the memory of the device and accessed by a microprocessor using an internal bus. The techniques and methods for embodying software programming code in memory, on physical media, and/or distributing software code via networks are well known and will not be further discussed herein.
Generally, program modules include routines, programs, objects, components, data structures and the like that perform particular tasks or implement particular abstract data types. Moreover, those skilled in the art will appreciate that the invention can be practiced with other computer system configurations, including hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, and the like. The invention may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote memory storage devices.
An exemplary system for implementing the invention includes a general purpose computing device such as the form of a conventional personal computer, a personal communication device or the like, including a processing unit, a system memory, and a system bus that couples various system components, including the system memory to the processing unit. The system bus may be any of several types of bus structures including a memory bus or memory controller, a peripheral bus, and a local bus using any of a variety of bus architectures. The system memory generally includes read-only memory (ROM) and random access memory (RAM). A basic input/output system (BIOS), containing the basic routines that help to transfer information between elements within the personal computer, such as during start-up, is stored in ROM. The personal computer may further include a hard disk drive for reading from and writing to a hard disk, a magnetic disk drive for reading from or writing to a removable magnetic disk. The hard disk drive and magnetic disk drive are connected to the system bus by a hard disk drive interface and a magnetic disk drive interface, respectively. The drives and their associated computer-readable media provide non-volatile storage of computer readable instructions, data structures, program modules and other data for the personal computer. Although the exemplary environment described herein employs a hard disk and a removable magnetic disk, it should be appreciated by those skilled in the art that other types of computer readable media which can store data that is accessible by a computer may also be used in the exemplary operating environment.
While there have been described above the principles of the present invention in conjunction with a densified fluid heat management system, it is to be clearly understood that the foregoing description is made only by way of example and not as a limitation to the scope of the invention. Particularly, it is recognized that the teachings of the foregoing disclosure will suggest other modifications to those persons skilled in the relevant art. Such modifications may involve other features that are already known per se and which may be used instead of or in addition to features already described herein. Although claims have been formulated in this application to particular combinations of features, it should be understood that the scope of the disclosure herein also includes any novel feature or any novel combination of features disclosed either explicitly or implicitly or any generalization or modification thereof which would be apparent to persons skilled in the relevant art, whether or not such relates to the same invention as presently claimed in any claim and whether or not it mitigates any or all of the same technical problems as confronted by the present invention. The Applicant hereby reserves the right to formulate new claims to such features and/or combinations of such features during the prosecution of the present application or of any further application derived therefrom.

Claims

1. A densified fluid treatment system, comprising:

a treatment system, wherein the treatment system includes

a densified fluid,

a distillation vessel,

a storage vessel closeably connected to the distillation vessel,

a treatment vessel for treatment of an article with the densified fluid at a hyper-atmospheric pressure and wherein the treatment vessel is connected to the storage vessel, and

a fluid displacement device, connected to and interposed between the treatment vessel and the distillation vessel, operable to transfer the densified fluid throughout the treatment system in a liquid state and/or in a vapor state, and compress the vapor state of the densified fluid into the liquid state of the densified fluid and wherein the distillation vessel continuously cleans the densified fluid used to treat the article;

a heat management system, wherein the heat management system includes

the densified fluid,

a compressor,

a distillation vessel heat exchanger connected to the compressor by a distillation heat supply line,

a storage vessel heat exchanger connected to the compressor by a compressor fill line wherein interposed between the storage vessel heat exchanger and the compressor is a compressor fill line heat exchanger, and

an expansion a valve interposed between the distillation vessel heat exchanger and the storage vessel heat exchanger and connected to the distillation vessel heat exchanger by a distillation heat return line and connected to the storage vessel heat exchanger by a storage fill line; and

a charge line closeably connecting the storage vessel of the treatment system to the compressor fill line to maintain volumetric content of the densified fluid within the heat management system.

2. The densified fluid treatment system of claim 1, wherein the compressor fill line heat exchanger is a plurality of heat exchangers configured in series.

3. The densified fluid treatment system of claim 1, wherein the compressor fill line heat exchanger is a plurality of heat exchangers configured in parallel.

4. The densified fluid treatment system of claim 1, wherein the compressor fill line heat exchanger is an adiabatic heat exchanger.

5. The densified fluid treatment system of claim 1, wherein the compressor fill line heat exchanger is operable to add heat to the heat management system.

6. The densified fluid treatment system of claim 1, further comprising a bypass heat exchanger connected to the distillation heat supply line and the distillation heat return line and operable to manage heat within the heat management system.

7. The densified fluid treatment system of claim 8, wherein the bypass heat exchanger removes heat from the heat management system.

8. The densified fluid treatment system of claim 8, wherein the bypass heat exchanger is a plurality of heat exchangers configured in series.

9. The densified fluid treatment system of claim 8, wherein the bypass heat exchanger is a plurality of heat exchangers configured in parallel.

10. The densified fluid treatment system of claim 1, wherein the compressor is a super critical adiabatic compressor.

11. The densified fluid treatment system of claim 1, wherein the distillation vessel heat exchanger resides within the distillation vessel.

12. The densified fluid treatment system of claim 1, wherein the storage vessel heat exchanger resides within the storage vessel.

13. The densified fluid treatment system of claim 1, wherein the densified fluid is carbon dioxide.

14. A method for heat management in a densified fluid treatment system, the method comprising:

combining a densified fluid treatment system with a heat management system wherein the densified fluid treatment system and the heat management are fluidly coupled using a common densified fluid; and

managing heat exchange within the densified fluid treatment system by the heat management system using the densified fluid of the densified fluid treatment system.

15. The method for heat management in a densified fluid treatment system according to claim 14, further comprising maintaining a volume of the densified fluid within the heat management system with densified fluid from the densified fluid treatment system.

16. The method for heat management in a densified fluid treatment system according to claim 14, wherein the densified fluid is carbon dioxide.

17. The method for heat management in a densified fluid treatment system according to claim 14, wherein the densified treatment system includes,

the densified fluid,

a distillation vessel,

a storage vessel closeably connected to the distillation vessel,

a treatment vessel for treatment an article with the densified fluid at a hyper-atmospheric pressure and wherein the treatment vessel is connected to the storage vessel, and

a fluid displacement device, connected to the treatment vessel and the distillation vessel, operable to transfer the densified fluid throughout the treatment system in a liquid state and in a vapor state, and compress the vapor state of the densified fluid into the liquid state of the densified fluid and wherein the distillation vessel continuously cleans the densified fluid treatment the article.

18. The method for heat management in a densified fluid treatment system according to claim 15, wherein the heat management system includes

the densified fluid

a compressor,

a storage vessel heat exchanger connected to the compressor by a compressor fill line wherein interposed between the storage vessel heat exchanger and the compressor is a compressor fill line heat exchanger,

an expansion a valve interposed between the distillation vessel heat exchanger and the storage vessel heat exchanger and connected to the distillation vessel heat exchanger by a distillation heat return line and connected to the storage vessel heat exchanger by a storage fill line.

19. The method for heat management in a densified fluid treatment system according to claim 14, connecting the storage vessel to the compressor fill line by a charge line to maintain volumetric content of the densified fluid within the heat management system.

20. A densified fluid treatment system, comprising:

a hyper-atmospheric treatment system including a densified fluid, a treatment vessel, a storage vessel, and a distillation vessel wherein the densified fluid is continuously cleaned within the distillation vessel during a treatment cycle; and

a heat management system for heat management of the hyper-atmospheric treatment system, the heat management system including a heat transfer fluid, and a plurality of heat exchangers, wherein one or more of the plurality of heat exchangers resides within each the distillation vessel and the storage vessel and wherein the heat transfer fluid is the densified fluid of the hyper-atmospheric treatment system.