REGENERATIVE THERMAL ENERGY SYSTEM AND METHOD OF OPERATING THE SAME

Abstract

A regenerative thermal energy system includes a heat exchange reactor that includes a top entry portion, a lower entry portion, and a bottom discharge portion. The system also includes at least one fluid source coupled in flow communication with the at least one heat exchange reactor at the lower entry portion. The system also includes at least one cold particle storage source coupled in flow communication with the at least one heat exchange reactor at the top entry portion. The system further includes at least one thermal energy storage (TES) vessel coupled in flow communication with the heat exchange reactor at each of the bottom discharge portion and the top entry portion. The heat exchange reactor is configured to facilitate direct contact and counter-flow heat exchange between solid particles and a fluid.

Description

BACKGROUND

The field of the invention relates generally to energy storage and, more particularly, to regenerative thermal energy storage (TES) systems associated with adiabatic compressed air energy storage (A-CAES) systems.

At least some known A-CAES systems use expansive containments, e.g., pressure vessels or underground caverns to store hot, compressed air. Storage facilities using man-made pressure vessels require sufficient containment wall strength to withstand high pressures induced by compressed air for extended periods of time. Also, these known pressure vessels are exposed to high temperatures due to the compression of the air stored within. Therefore, some known pressure vessels are fabricated from expensive metal alloys with thick walls to withstand temperatures of approximately 450 degrees Celsius (° C.) (842 degrees Fahrenheit (° F.)). Other known containments include thick concrete walls with complex structures to facilitate gas tightness at high pressures. Such concrete walls are typically constructed to withstand temperatures of approximately 100° C. (212° F.), and therefore, require an active cooling system.

Such known containments, whether man-made or natural caverns, require a significant amount of thermal insulation to facilitate decreasing heat transfer to the local environment, thereby preserving as much thermal energy as possible for later conversion. Therefore, due to the large volumes required, thermal energy storage within A-CAES systems requires a substantial capital investment to merely reduce heat transfer from the stored, compressed gases.

At least some known A-CAES systems include fixed-matrix regenerators within a stand-alone vessel that includes an inventory of solid mass. The solid mass stores thermal energy as hot air is channeled over the solid mass. Also, the solid mass releases thermal energy as cold air is channeled over the solid mass.

However, the walls of these stand-alone vessels must provide sufficient strength to withstand the pressures of the air channeled therethrough. Therefore, strengthening the walls will increase the capital construction costs of the A-CAES systems. Also, at least some known A-CAES systems include indirect heat transfer systems that use equipment to facilitate substantial heat losses.

BRIEF DESCRIPTION

In one aspect, a regenerative thermal energy system is provided. The system includes a heat exchange reactor that includes a top entry portion, a lower entry portion, and a bottom discharge portion. The system also includes at least one fluid source coupled in flow communication with the at least one heat exchange reactor at the lower entry portion. The system also includes at least one cold particle storage source coupled in flow communication with the at least one heat exchange reactor at the top entry portion. The system further includes at least one thermal energy storage (TES) vessel coupled in flow communication with the heat exchange reactor at each of the bottom discharge portion and the top entry portion. The heat exchange reactor is configured to facilitate direct contact and counter-flow heat exchange between solid particles and a fluid.

In a further aspect, a power generation facility is provided. The facility includes at least one power generation apparatus and at least one regenerative thermal energy system coupled to the at least one power generation apparatus. The at least one regenerative thermal energy system includes a heat exchange reactor that includes a top entry portion, a lower entry portion, and a bottom discharge portion. The system also includes at least one fluid source coupled in flow communication with the at least one heat exchange reactor at the lower entry portion. The system further includes at least one cold particle storage source coupled in flow communication with the at least one heat exchange reactor at the top entry portion. The system also includes at least one thermal energy storage (TES) vessel coupled in flow communication with the heat exchange reactor at each of the bottom discharge portion and the top entry portion, wherein the heat exchange reactor is configured to facilitate direct contact and counter-flow heat exchange between solid particles and a fluid and channel hot pressurized air to the at least one power generation apparatus.

In another aspect, a method of operating a power generation facility is provided. The method includes channeling solid particles downward through a heat exchange reactor and channeling pressurized air upward through the heat exchange reactor. The method also includes transferring heat from the pressurized air to the solid particles through direct contact. The method further includes channeling the solid particles into at least one thermal energy storage (TES) vessel.

DRAWINGS

These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

FIG. 1 is a schematic view of a first portion of an exemplary regenerative thermal energy system.

FIG. 2 is a flow chart of a method of charging the regenerative thermal energy system shown in FIG. 1.

FIG. 3 is a schematic view of a second portion of the regenerative thermal energy system partially shown in FIG. 1.

FIG. 4 is a flow chart of a method of discharging the regenerative thermal energy system shown in FIG. 3.

FIG. 5 is a schematic view of an exemplary power generation facility that uses the regenerative thermal energy system shown in FIGS. 1 and 3.

Unless otherwise indicated, the drawings provided herein are meant to illustrate key inventive features of the invention. These key inventive features are believed to be applicable in a wide variety of systems comprising one or more embodiments of the invention. As such, the drawings are not meant to include all conventional features known by those of ordinary skill in the art to be required for the practice of the invention.

DETAILED DESCRIPTION

In the following specification and the claims, reference will be made to a number of terms, which shall be defined to have the following meanings.

The singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise.

“Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not.

Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about” and “substantially”, are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise.

FIG. 1 is a schematic view of a first portion 102 of an exemplary regenerative thermal energy system 100. First portion 102 includes the components of system 100 used during a charging operation, i.e., when a solid mass (described further below) is charged with thermal energy for storage.

In the exemplary embodiment, regenerative thermal energy system 100 includes a heat exchange reactor 110 including a plurality of walls 112 that define a fully enclosed heat transfer cavity 114. Walls 112 also define a top entry portion 116 coupled in flow communication with at least one cold particle storage source 118. Cold particle storage source 118 is any containment and delivery system that enables operation of regenerative thermal energy system 100 as described herein, including, without limitation, hoppers, bins, silos, solids transfer devices, and gravity-feed devices. Storage source 118 and top entry portion 116 cooperate to inject small, cold, solid particles 119 into heat transfer cavity 114. Particles 119 are any solids that enable operation of regenerative thermal energy system 100 as described herein, including, without limitation, sand.

Also, in the exemplary embodiment, walls 112 define a lower entry portion 120 that is coupled in flow communication with at least one fluid source, i.e., an air compressor 122, e.g., without limitation, a multi-stage air compressor. Alternatively, any fluid, including liquid and gas, that enables operation of regenerative thermal energy system 100 as described herein is used. Also, alternatively, system 100 includes a staged air compression system (not shown) with a plurality of air compressors 122 coupled in series. Further, alternatively, lower entry portion 120 defines a plurality of air inlet ports (not shown) that may be coupled to an air inlet manifold (not shown). Air compressor 122 is coupled to an electric motor 124. Alternatively, air compressor 122 is driven by any mechanism that enables operation of regenerative thermal energy system 100 as described herein, including, without limitation, a steam turbine, a gas turbine, a water turbine, a wind turbine, a gasoline combustion engine, and a diesel engine, all with geared couplings as necessary. Air compressor 122 is configured to receive cold, ambient air 126 and discharge hot, compressed air 128 into heat transfer cavity 114, as described further below.

In the exemplary embodiment, regenerative thermal energy system 100 includes moisture removal apparatus configured to remove moisture from compressed air prior to injection of hot, compressed air 128 into heat transfer cavity 114. Such moisture removal apparatus includes at least one of an upstream moisture separator 123 coupled in flow communication with air compressor 122 upstream of air compressor 122, downstream moisture separator 125 coupled in flow communication with air compressor 122 downstream of air compressor 122, and a plurality of interstage moisture separators 127 within air compressor 122. Each of upstream moisture separator 123, downstream moisture separator 125, and interstage moisture separators 127 facilitate removal of water 129 from the air.

Further, in the exemplary embodiment, walls 112 define an inwardly inclined bottom discharge portion 130 configured to facilitate storage of hot solid particles 132. Bottom discharge portion 130 is also configured to facilitate discharge of hot solid particles 132 out of heat transfer cavity 114 with the assistance of gravity.

Moreover, in the exemplary embodiment, regenerative thermal energy system 100 includes at least one cyclone filter 140 coupled in flow communication with heat transfer cavity 114 through an air extraction conduit 142. Conduit 142 is positioned between top entry portion 116 and lower entry portion 120, and is configured to direct cold, pressurized air 144 and entrained particles 146 from heat transfer cavity 114 to cyclone filter 140. At least one cold, pressurized air storage vessel 148 is coupled in flow communication with cyclone filter 140. Also, cyclone filter 140 includes a sloped portion 150 configured to retain entrained particles 146. Storage source 118 is coupled in flow communication with sloped portion 150.

Also, in the exemplary embodiment, regenerative thermal energy system 100 includes at least one thermal energy storage (TES) vessel 160 coupled in flow communication with heat exchange reactor 110 at bottom discharge portion 130. TES vessel 160 defines a particle storage cavity 162 configured to receive and store hot solid particles 132 therein. Cavity 162 is sufficiently sized to enable operation of regenerative thermal energy system 100 through one full cycle as described herein. TES vessel 160 includes an insulation layer 164 that is sufficient to enable maintaining hot solid particles 132 within a predetermined temperature range through one full cycle of regenerative thermal energy system 100 as described herein. For example, and without limitation, insulation layer 164 facilitates maintaining hot solid particles 132 within the predetermined temperature range for 12 to 24 hours. TES vessel 160 is configured to operate at approximately atmospheric pressure.

Further, in the exemplary embodiment, regenerative thermal energy system 100 includes at least one solids transfer pump 166 coupled in flow communication with TES vessel 160. Pump 166 is configured to transfer hot particles 168 from TES vessel 160 as described further below. In the exemplary embodiment, solids transfer pump 166 is a GE Posimetric® pump commercially available from GE Energy, Atlanta, Ga., USA. Alternatively, any pumping device that enables operation of regenerative thermal energy system 100 as described herein is used.

Also, in the exemplary embodiment, regenerative thermal energy system 100 includes at least one device configured to increase a residence time of solid particles 119 and hot, compressed air 128. For example, without limitation, a plurality of air and particle deflector devices 163 are coupled to walls 112 within heat transfer cavity 114 and extend inward therefrom. Also, for example, and without limitation, air and particle deflector devices 163 and walls 112 define a tortuous heat transfer channel 165. Further, for example, and without limitation, heat transfer projections 167, e.g., without limitation, heat fins, are positioned within channel 165. Deflector devices 163, channel 165, and projections 167 facilitate increasing the residence time to further facilitate heat transfer between particles 119 and air 128.

FIG. 2 is a flow chart of a method 200 of charging regenerative thermal energy system 100 (shown in FIG. 1). During the charging operation, small, cold, solid particles 119 (shown in FIG. 1) are injected 202 into heat transfer cavity 114 from storage source 118 through top entry portion 116 (all shown in FIG. 1). Particles 119 are injected within a temperature range between approximately 0 degrees Celsius (° C.) (32 degrees Fahrenheit (° F.)) and approximately 49° C. (120° F.). Alternatively, particles 119 are injected within any temperature range that enables operation of regenerative thermal energy system 100 as described herein. Particles 119 are injected at any pressures that enable operation of regenerative thermal energy system 100 as described herein.

Also, during the charging operation, particles 119 are directed 204 downward through heat exchange reactor 110 (shown in FIG. 1) with the assistance of gravity. Cold, ambient air 126 (shown in FIG. 1) is received and compressed 206 by air compressor 122 (shown in FIG. 1). Ambient air 126 is in a temperature range between approximately 0° C. (32° F.) and approximately 49° C. (120° F.), and has an atmospheric pressure of approximately one atmosphere, i.e., 1.015 bar, 101.353 kilo-Pascal (kPa), and 14.7 pounds per square inch (psi). Alternatively, inlet air 126 to air compressor 122 has temperatures and pressures in any range that enables operation of regenerative thermal energy system 100 as described herein.

Further, during the charging operation, air compressor 122 discharges 208 hot, compressed air 128 (shown in FIG. 1) into heat transfer cavity 114 with a temperature range between approximately 250° C. (482° F.) and approximately 700° C. (1292° F.), and a pressure range between approximately 20 bar (2000 kPa, 290 psi) and approximately 70 bar (7000 kPa, 1015 psi). Alternatively, hot, compressed air 128 discharged from air compressor 122 has temperatures and pressures in any range that enables operation of regenerative thermal energy system 100 as described herein. Hot, compressed air 128 is channeled 210 upward through heat transfer cavity 114.

Moreover, during the charging operation, since particles 119 and air 128 flow counter to each other, particles 119 and air 128 come into direct contact with each other within heat transfer cavity 114. Such direct contact between air 128 and particles 119 facilitates heat exchange therebetween such that air 128 transfers 212 thermal energy to particles 119. The heat exchange generates hot solid particles 132, cold, pressurized air 144, and entrained particles 146 (all shown in FIG. 1). Deflector devices 163, channel 165, and projections 167 facilitate increasing the residence time to further facilitate heat transfer between particles 119 and air 128.

Also, during the charging operation, cold, pressurized air 144 and entrained particles 146 are extracted 214 from heat transfer cavity 114 to cyclone filter 140 that uses cyclonic action to separate 216 air 144 from particles 146. Air 144 is directed 218 to at least one cold, pressurized air storage vessel 148. Air 144 has a temperature value within a range between approximately 20° C. (68° F.) and 60° C. (140° F.) and within a pressure range between approximately 20 bar (2000 kPa, 290 psi) and approximately 70 bar (7000 kPa, 1015 psi). Alternatively, air 144 is within any temperature range that enables operation of regenerative thermal energy system 100 as described herein.

Further, during the charging operation, entrained particles 146 are directed 220 downward through cyclone filter 140 with the assistance of gravity and are stored at sloped portion 150 (shown in FIG. 1) of cyclone filter 140. Particles 146 have a temperature value within a range between approximately 20° C. (68° F.) and approximately 60° C. (140° F.). Alternatively, particles 146 are within any temperature range that enables operation of regenerative thermal energy system 100 as described herein. Particles 146 are channeled to cold particle storage source 118 for regenerative use.

Moreover, during the charging operation, hot solid particles 132 are deposited at inwardly inclined bottom discharge portion 130. Hot solid particles 132 are transferred 222 out of heat transfer cavity 114 to TES vessel 160 with the assistance of gravity. TES vessel 160 receives and stores hot solid particles 132 within particle storage cavity 162. Hot solid particles 132 are maintained 224 within a predetermined temperature range between approximately 240° C. (464° F.) and approximately 690° C. (1274° F.) through one full cycle of regenerative thermal energy system 100 as described herein. For example, and without limitation, hot solid particles 132 are maintained within the exemplary temperature range for approximately 12 to approximately 24 hours. TES vessel 160 is maintained at approximately atmospheric pressure.

FIG. 3 is a schematic view of a second portion 170 of regenerative thermal energy system 100. Second portion 170 includes the components of system 100 used during a discharging operation, i.e., when thermal energy stored within a hot solid mass (described further below) is liberated to generate power. Many of the same components of system 100 used in first portion 102 (shown in FIG. 1) for charging operations described above are also used for discharging operations.

As described above, in the exemplary embodiment, regenerative thermal energy system 100 includes at least one solids transfer pump 166 coupled in flow communication with TES vessel 160. Solids transfer pump 166 is also coupled in flow communication with heat transfer cavity 114 of heat exchange reactor 110 through top entry portion 116. Solids transfer pump 166 is configured to transfer hot particles 168 from TES vessel 160 into heat transfer cavity 114.

Also, as described above, stored, cold, pressurized air 144 is contained in air storage vessel 148 within a pressure range between approximately 20 bar (2000 kPa, 290 psi) and approximately 70 bar (7000 kPa, 1015 psi). Therefore, solids transfer pump 166 is configured to inject particles 168 into heat exchange reactor 110 with sufficient pressure to overcome the pressure of air 144.

Further, as described above, cyclone filter 140 is coupled in flow communication with heat transfer cavity 114 through air extraction conduit 142. Cyclone filter 140 is further coupled in flow communication with heat transfer cavity 114 through an entrained particle return conduit 175.

Moreover, in the exemplary embodiment, regenerative thermal energy system 100 includes at least one expander 180 rotatably coupled to a machine, e.g., without limitation, a generator 182. Expander 180 is coupled in flow communication with cyclone filter 140.

In at least some alternative embodiments, regenerative thermal energy system 100 includes at least one combustion apparatus 181 coupled in flow communication with cyclone filter 140 and expander 180. Combustion apparatus 181 includes a hot air extension line 183 coupled to cyclone filter 140. Combustion apparatus 181 also includes a fuel line 185. Combustion apparatus 181 further includes an air/fuel mixer 186 coupled to hot air extension line 183 and fuel line 185. Combustion apparatus 181 also includes a combustion chamber 187 coupled to air/fuel mixer 186 and hot air extension line 183. Combustion apparatus 181 further includes a heat exchange device 188 coupled to combustion chamber 187, hot air extension line 183, and expander 180. Combustion apparatus 181 further includes an exhaust conduit 189 coupled to heat exchange device 188.

FIG. 4 is a flow chart of a method 300 of discharging regenerative thermal energy system 100 (shown in FIG. 3). During the discharging operation, hot solid particles 132 (shown in FIG. 3) are maintained 302 within a predetermined temperature range between approximately 240° C. (464° F.) and approximately 690° C. (1274° F.) through one full cycle of regenerative thermal energy system 100 as described herein. For example, and without limitation, hot solid particles 132 are maintained within the exemplary temperature range for 12 to 24 hours. TES vessel 160 (shown in FIG. 3) is maintained at approximately atmospheric pressure. Hot particles 168 (shown in FIG. 3) are transferred from TES vessel 160 into heat transfer cavity 114 (shown in FIG. 3) through top entry portion 116 (shown in FIG. 3) within a similar temperature range.

Also, during the discharging operation, and as described above, cold, pressurized air 144 is contained 304 in air storage vessel 148 (shown in FIG. 3). Air 144 has a temperature value within a range between approximately 20° C. (68° F.) and 60° C. (140° F.) and within a pressure range between approximately 20 bar (2000 kPa, 290 psi) and approximately 70 bar (7000 kPa, 1015 psi). Stored, cold, pressurized air 144 is discharged 306 into heat transfer cavity 114. Air 144 is directed 308 upward through heat transfer cavity 114. Solids transfer pump 166 (shown in FIG. 3) injects 310 particles 168 into heat exchange reactor 110 with sufficient pressure to overcome the pressure of air 144.

Further, during the discharging operation, since particles 168 and air 144 flow counter to each other, particles 168 and air 144 come into direct contact with each other within heat transfer cavity 114. Such direct contact between air 144 and particles 168 facilitates heat exchange therebetween such that particles 168 transfers 312 thermal energy to air 144. The heat exchange generates hot, pressurized air 172, entrained particles 174, and cold particles 190 (all shown in FIG. 3).

Moreover, during the discharging operation, hot, pressurized air 172 and entrained particles 174 are extracted 314 from heat transfer cavity 114 to cyclone filter 140 (shown in FIG. 3) that uses cyclonic action to separate 316 air 172 from particles 174. Hot, pressurized air 172 and entrained particles 174 are within a temperature range of approximately 240° C. (464° F.) and approximately 690° C. (1274° F.).

Also, during the discharging operation, entrained particles 174 are directed 318 downward through cyclone filter 140 with the assistance of gravity and are stored at sloped portion 150 (shown in FIG. 3) of cyclone filter 140. Some reusable, i.e., still transferable, thermal energy may reside within particles 174. Therefore, such particles 174 within a temperature range between approximately 240° C. (464° F.) and approximately 690° C. (1274° F.) are reinjected 320 into heat transfer cavity 114 for further thermal energy transfer to air 144. Alternatively, particles 174 are reinjected into heat transfer cavity 114 within any temperature range that enables operation of regenerative thermal energy system 100 as described herein. As the temperatures of particles 174 attains a value within a predetermined range between approximately 20° C. (68° F.) and approximately 60° C. (140° F.), particles 174 are transferred 322 to cold particle storage source 118 for regenerative use. Alternatively, particles 174 are channeled to cold particle storage source 118 within any temperature range that enables operation of regenerative thermal energy system 100 as described herein.

Further, during the discharging operation, some cold particles 190 that have been substantially exhausted of transferrable thermal energy are deposited at inwardly inclined bottom discharge portion 130 (shown in FIG. 3). Particles 190 are transferred 324, with the assistance of gravity, out of heat transfer cavity 114 to TES vessel 160 in a manner that reduces a probability of cannibalizing thermal energy stored in hot particles 132. TES vessel 160 receives and stores cold particles 190 within particle storage cavity 162. Cold particles 190 are transferred 326 to cold particle storage source 118 for regenerative use.

Moreover, during the discharging operation, hot, pressurized air 172 having a temperature value within a range between approximately 240° C. (464° F.) and approximately 690° C. (1274° F.) and within a pressure range between approximately 20 bar (2000 kPa, 290 psi) and approximately 70 bar (7000 kPa, 1015 psi) is directed 328 to expander 180 (shown in FIG. 3). Alternatively, air 172 is within any temperature range and any pressure range that enables operation of regenerative thermal energy system 100 as described herein. Expander 180 (shown in FIG. 3) drives 330 generator 182 (shown in FIG. 3) and expended air 184 (shown in FIG. 3) is discharged to any place that enables operation of regenerative thermal energy system 100 as described herein.

In at least some alternative embodiments, the hot air from cyclone filter 140 is channeled to combustion apparatus 181 through conduit 183. Some of the hot air and fuel are channeled to air/fuel mixer 186 through conduit 183 and fuel line 185, respectively, where they are mixed. The air/fuel mixture is channeled to combustion chamber 187 and additional hot air in injected into combustion chamber 187 from conduit 183. Hot gases are generated and are channeled to heat exchange device 188. Heat transfer from the gases to hot air channeled from conduit 183 further increases the temperature of air 172 prior to expander 180. The combustion gases are channeled through exhaust conduit 189

FIG. 5 is a schematic view of an exemplary power generation facility 500 that uses regenerative thermal energy system 100. In the exemplary embodiment, power generation facility 500 includes a plurality of power generators 502, including, without limitation, steam turbine generators, gas turbine generators, water turbine generators, wind turbine generators, gasoline combustion engine-driven generators, and diesel engine generators, and any combination thereof.

One example, without limitation, of operating power generation facility 500 includes storing thermal energy during non-peak periods and expending the stored thermal energy during peak periods. During non-peaking generation periods, an own/operator of power generation facility anticipates a need for additional power generation during a future peaking period. Power generators 502 transmit electric power to electric motors 124 of air compressors 122 (shown in FIG. 1) and thermal energy is stored in regenerative thermal energy system 100 as described above. During peaking periods, regenerative thermal energy system 100 substantially recovers the stored thermal energy and electric power that is generated by generators 182 is added to the electric power generated by power generators 502 for transmission. Such regenerative operation, including a charging and discharging operations, represents a full cycle of regenerative thermal energy system 100. As an example, without limitation, such cycles may occur twice on weekdays, i.e., discharging operations are performed between approximately 5:00 AM and approximately 9:00 AM, and again approximately 5:00 PM and approximately 10:00 PM. Charging operations are performed between those two time periods when discharging operations are not in progress. Alternatively, some embodiments of power generation facility 500 may include multiple iterations of regenerative thermal energy system 100 such that one system 100 is charging and feeding a second system 100 that is discharging.

The above-described regenerative thermal energy system provides a cost-effective method for generating and storing thermal energy for later use. The embodiments described herein facilitate storing thermal energy in a thermal energy storage vessel during low power usage periods for future use during peak power usage periods. Specifically, the devices, systems, and methods described herein facilitate transferring heat from hot compressed air to and the assistance of gravity small, cold, solid particles through direct contact. More specifically, the devices, systems, and methods described herein facilitate using a power generation facility to use at least some of the power generated therein to drive air compressors during low power usage periods. The thermal energy now contained in the hot, small particles is stored with the particles in an insulated vessel configured to maintain the particles within a specific temperature range for a certain period of time at atmospheric pressure. The cold, pressurized air is channeled to a storage vessel. During periods of high power usage, the hot particles are channeled to mix with the stored, cold, pressurized air to transfer the thermal energy back into the air. The reheated air is channeled to an expander coupled to a generator. Therefore, since the small hot particles are stored in a smaller vessel than that use to store the air, use of more robust structural materials and insulation for air storage is no longer required. Moreover, since the particles and air are in direct contact, equipment necessary to facilitate indirect thermal energy transfer is not required.

An exemplary technical effect of the methods, systems, and apparatus described herein includes at least one of: (a) decreasing the volume of a vessel used to store thermal energy; and (b) directly contacting cold particles with hot air and hot particles with cold air to regeneratively transfer thermal energy therebetween.

Exemplary embodiments of regenerative thermal energy system for power generation facilities and methods for operating are described above in detail. The regenerative thermal energy system, power generation facilities, and methods of operating such systems and facilities are not limited to the specific embodiments described herein, but rather, components of systems and/or steps of the methods may be utilized independently and separately from other components and/or steps described herein. For example, the methods may also be used in combination with other systems requiring thermal energy storage and methods, and are not limited to practice with only the regenerative thermal energy system, power generation facilities, and methods as described herein. Rather, the exemplary embodiment can be implemented and utilized in connection with many other thermal energy storage and transfer applications.

Although specific features of various embodiments of the invention may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the invention, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing.

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

1. A regenerative thermal energy system comprising:

a heat exchange reactor comprising a top entry portion, a lower entry portion, and a bottom discharge portion;

at least one fluid source coupled in flow communication with said at least one heat exchange reactor at said lower entry portion;

at least one cold particle storage source coupled in flow communication with said at least one heat exchange reactor at said top entry portion; and

at least one thermal energy storage (TES) vessel coupled in flow communication with said heat exchange reactor at each of said bottom discharge portion and said top entry portion, wherein said heat exchange reactor is configured to facilitate direct contact and counter-flow heat exchange between solid particles and a fluid.

2. A regenerative thermal energy system in accordance with claim 1, wherein said at least one fluid source comprises at least one fluid compressor and at least one fluid storage source, wherein said at least one fluid compressor is configured to channel fluid at a first temperature into said heat exchange reactor and said at least one fluid storage source is configured to channel fluid at a second temperature into said heat exchange reactor, wherein the first temperature is greater than the second temperature.

3. A regenerative thermal energy system in accordance with claim 2 further comprising at least some moisture removal apparatus comprising at least one of:

at least one moisture removal apparatus coupled in flow communication with said at least one fluid compressor upstream of said at least one fluid compressor;

at least one moisture removal apparatus coupled in flow communication with said at least one fluid compressor downstream of said at least one fluid compressor; and

at least one interstage moisture removal apparatus within said at least one fluid compressor.

4. A regenerative thermal energy system in accordance with claim 1 further comprising at least one solids transfer pump coupled in flow communication with said at least one TES vessel and said top entry portion of said heat exchange reactor.

5. A regenerative thermal energy system in accordance with claim 1 further comprising at least one cyclone filter coupled in flow communication with said heat exchange reactor between said top entry portion and said lower entry portion, wherein said at least one cyclone filter is configured to receive fluid exiting said heat exchange reactor and solid particles entrained therein.

6. A regenerative thermal energy system in accordance with claim 5, wherein said at least one cyclone filter is further coupled in flow communication with said at least one cold particle storage source.

7. A regenerative thermal energy system in accordance with claim 1, wherein said at least one TES vessel comprises at least some insulation and is configured to contain solid particles within a predetermined range of temperatures for a predetermined period of time.

8. A regenerative thermal energy system in accordance with claim 1, wherein said at least one heat exchange reactor defines a heat transfer cavity therein that is configured to facilitate the direct contact and the counter-flow heat exchange between the solid particles and the fluid, said heat transfer cavity at least partially encloses at least one device configured to increase a residence time of the solid particles and the fluid, said at least one device comprises at least one of:

at least one fluid and particle deflector device;

at least one heat transfer projection; and

at least one heat transfer channel.

9. A power generation facility comprising:

at least one power generation apparatus; and

at least one regenerative thermal energy system coupled to said at least one power generation apparatus, said at least one regenerative thermal energy system comprising: a heat exchange reactor comprising a top entry portion, a lower entry portion, and a bottom discharge portion; at least one fluid source coupled in flow communication with said at least one heat exchange reactor at said lower entry portion; at least one cold particle storage source coupled in flow communication with said at least one heat exchange reactor at said top entry portion; and at least one thermal energy storage (TES) vessel coupled in flow communication with said heat exchange reactor at each of said bottom discharge portion and said top entry portion, wherein said heat exchange reactor is configured to facilitate direct contact and counter-flow heat exchange between solid particles and a fluid and channel hot pressurized air to said at least one power generation apparatus.

10. A power generation facility in accordance with claim 9, wherein said at least one fluid source comprises at least one fluid compressor and at least one fluid storage source, wherein said at least one fluid compressor is configured to channel fluid at a first temperature into said heat exchange reactor and said at least one fluid storage source is configured to channel fluid at a second temperature into said heat exchange reactor, wherein the first temperature is greater than the second temperature.

11. A power generation facility in accordance with claim 9 further comprising at least one cyclone filter coupled in flow communication with said heat exchange reactor between said top entry portion and said lower entry portion, wherein said at least one cyclone filter is configured to receive fluid exiting said heat exchange reactor and solid particles entrained therein.

12. A power generation facility in accordance with claim 11, wherein said at least one cyclone filter is further coupled in flow communication with said at least one cold particle storage source and said at least one power generation apparatus.

13. A power generation facility in accordance with claim 9, wherein said at least one TES vessel comprises at least some insulation and is configured to contain solid particles within a predetermined range of temperatures for a predetermined period of time.

14. A power generation facility in accordance with claim 9 further comprising at least one combustion apparatus coupled in flow communication with said at least one cyclone filter and said at least one power generation apparatus.

15. A method of operating a power generation facility, said method comprising:

channeling solid particles downward through a heat exchange reactor;

channeling pressurized air upward through the heat exchange reactor;

transferring heat from the pressurized air to the solid particles through direct contact; and

channeling the solid particles into at least one thermal energy storage (TES) vessel.

16. The method in accordance with claim 15 further comprising:

channeling the solid particles from the TES vessel downward through the heat exchange reactor;

channeling pressurized air upward through the heat exchange reactor;

transferring heat from the solid particles to the pressurized air through direct contact; and

channeling the pressurized air to at least one power generation apparatus.

17. The method in accordance with claim 15, wherein channeling solid particles downward through a heat exchange reactor comprises injecting the solid particles at the top of the heat exchange reactor and channeling the solid particles downward with the assistance of gravity.

18. The method in accordance with claim 15, wherein channeling pressurized air upward through the heat exchange reactor comprises channeling the air through a cyclone filter to remove at least a portion of solid particles entrained therein.

19. The method in accordance with claim 15, wherein channeling the solid particles into at least one thermal energy storage (TES) vessel comprises containing the solid particles within a predetermined temperature range for a predetermined period of time.

20. The method in accordance with claim 15 further comprising:

wherein: operating the heat exchange reactor at a first pressure; and operating the at least one TES vessel at a second pressure, wherein the first pressure is greater than the second pressure, and the second pressure has a value that is approximately atmospheric pressure.