JP2005533972A - Cascading closed-loop cycle power generation - Google Patents

Cascading closed-loop cycle power generation Download PDF

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JP2005533972A
JP2005533972A JP2005505522A JP2005505522A JP2005533972A JP 2005533972 A JP2005533972 A JP 2005533972A JP 2005505522 A JP2005505522 A JP 2005505522A JP 2005505522 A JP2005505522 A JP 2005505522A JP 2005533972 A JP2005533972 A JP 2005533972A
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energy
fluid
stream
amount
working fluid
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スティンガー、ダニエル・エイチ
ミアン、ファールーク・アスラム
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スティンガー、ダニエル・エイチ
ミアン、ファールーク・アスラム
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Priority to US10/199,257 priority Critical patent/US6857268B2/en
Priority to US10/377,114 priority patent/US7096665B2/en
Application filed by スティンガー、ダニエル・エイチ, ミアン、ファールーク・アスラム filed Critical スティンガー、ダニエル・エイチ
Priority to PCT/US2003/022399 priority patent/WO2004009965A1/en
Publication of JP2005533972A publication Critical patent/JP2005533972A/en
Application status is Granted legal-status Critical

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01KSTEAM ENGINE PLANTS; STEAM ACCUMULATORS; ENGINE PLANTS NOT OTHERWISE PROVIDED FOR; ENGINES USING SPECIAL WORKING FLUIDS OR CYCLES
    • F01K25/00Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for
    • F01K25/08Plants or engines characterised by use of special working fluids, not otherwise provided for; Plants operating in closed cycles and not otherwise provided for using special vapours
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/40Solar thermal energy
    • Y02E10/46Conversion of thermal power into mechanical power, e.g. Rankine, Stirling solar thermal engines

Abstract

Cascading closed-loop cycle (CCLC) system (100) and super-cascading closed-loop cycle (super CCLC) system that restores waste heat of steam turbine system to mechanical or electrical energy. Waste heat from the boiler (106) and condenser (118) is used to evaporate propane and other light hydrocarbon fluids in a plurality of indirect heat exchangers (110, 114), and the evaporated propane is useful. It is recovered by expanding in a plurality of cascading expansion turbines (108, 116) to generate power and condensing into liquid using a cooling system. The liquid propane is then pressurized with the pump (102) and returned to the indirect heat exchanger, and the evaporation, expansion, liquefaction and pressurization cycles are repeated in a closed and sealed process.

Description

  The present invention relates to an apparatus and method for generating energy. In particular, the present invention relates to the use of cascading closed-loop cycles that use specific devices and fluids that can be used in combination with conventional power generation systems to extract useful additional energy from conventional power generation processes.

  The primary process used for power generation is to burn fossil fuel to heat the air. This hot air, or thermal energy, is then used to warm the liquid power generation medium (usually water) in the boiler to produce gas (steam), which steam crosses the steam turbine that operates the power plant. Inflates to. The unit of thermal energy is the British thermal unit, ie BTU. Other energy sources used to generate electricity by heating air and / or water in this way are: heat from nuclear reactions; heat from gas turbine exhaust; combustion of incinerator waste or other combustible materials Heat from.

  The steam turbine system used for power generation is generally a closed loop system, where pressurized water is evaporated in a boiler or heat exchanger, and in a steam turbine where the pressure level decreases as power is generated. Expanded; condensed in condenser or cooler and returned to water; water is pumped and returned to the boiler, repeating the cycle. There are two main sources of waste energy in the process of making steam in this closed loop system. The first source is waste heat leaving the boiler in the form of hot combustion exhaust gas (usually heated air). This is due to the inherent design and thermal characteristics of the water-steam conversion process that not all of the useful thermal energy (heat) of the flue gas can be used. The second source is the latent heat of evaporation that dissipates to the atmosphere during the process of condensing and returning the steam back to the water, that is, the amount of energy required to convert water to steam.

  In the first example of waste heat, the boiler heat source must provide thermal energy (in the form of hot flue gas). This thermal energy not only provides 1000 BTU / lb for converting water to steam, but also provides the steam with a high energy level sufficient to provide enough energy to drive the steam turbine to generate power. Must be able to overheat up to. The thermal requirements for this steam cycle limit the temperature difference required to produce superheated steam to the temperature difference between the original heat source temperature and about 204-260 ° C (about 400-500 ° F). As a result, the temperature of the flue gas exiting the boiler is about 204-260 ° C (about 400-500 ° F). Part of the energy of the flue gas is recovered, for example by using that energy to heat the power plant and using it to preheat boiler water or using other known methods The amount of useful energy is limited.

  In the second example of waste heat, the energy of the thermal form necessary to change the liquid state to gas is controlled by the thermodynamic properties of the liquid. The pressure and associated temperature at which a fluid becomes vapor is defined as the vapor pressure of that fluid. For any liquid, there are specific ranges of pressure and temperature at which the liquid becomes vapor. The BTU required to convert liquid to gas at vapor pressure is defined as “heat of vaporization”. The heat of vaporization of water is about 1000 BTU / lb. At the vapor pressure at which water turns into steam, the amount of residual energy in the vapor is only that amount necessary to maintain the state of the vapor and is defined as “heat of evaporation (or latent heat of vaporization)”. At the vapor pressure point, if the vapor is cooled in the condenser or the pressure decreases through the expansion process, the vapor releases heat of vaporization and returns from the gaseous state to the liquid state. That is, 1000 BTU / lb will be released to the surroundings to increase the heat energy, i.e. temperature, of the refrigerant. As such, even if useful energy is present, little useful energy can be extracted from the vapor that only contains the heat of evaporation. Because such steam quickly condenses due to expansion in the turbine, causing dramatic inefficiencies and possibly damaging the turbine. The physical phenomenon of heat of vaporization generates waste heat in the conventional power generation cycle. This is because this amount of heat must be transferred to liquid water before it turns into a useful gas phase, but this heat cannot be extracted as useful energy. When the medium is cooled back to liquid so that the medium is at the required pressure by the pump, this latent heat is released without being recovered as a useful form of energy. Therefore, the heat energy released to the atmosphere through the refrigerant that returns water to liquid is waste heat.

  As fuel costs increase and energy sources are exhausted, heat is converted into useful power (including power, the same in this specification and claims), and more efficient in the burning of fossil fuels Getting power is the most important. In addition, the negative environmental effects caused by the pollution generated from the combustion of fossil fuels are directed towards designing power plants to reduce the generated pollutants per unit of energy produced. . These factors create the efficiency of the power plant, as well as the need to enhance the recovery of energy from the waste heat generated in the power plant, waste heat from various manufacturing processes and heat energy from renewable energy sources. .

  Various methods and processes are used to increase the efficiency of power systems that convert fossil fuels into usable energy. These efficiency enhancing systems include gas turbine combined cycle plants, cogeneration plants and waste heat recovery systems. Cogeneration systems and combined cycle systems generate useful energy from the waste heat of gas turbine exhaust or other fossil fuel heat sources, including low grade calorific fuel sources, by using the heat of combustion that generates steam. In systems that use water as the primary medium for power generation, the temperature of the heat source (usually high-temperature flue gas from fossil fuel combustion) is sufficient to evaporate the water and generate steam in the heat exchanger (boiler). Must be high. The resulting steam expands in the steam turbine to generate power. Steam boilers are generally limited to recovering thermal energy related to the temperature difference between the initial temperature of the heat source and a temperature of about 260 ° C. (about 500 ° F.) or higher. This is because this is the temperature required to give the water an efficient thermal energy transition to generate steam. Further, the available heat for transferring energy to the steam is limited by the temperature differential limit imposed by the steam pressure vs. temperature characteristics of the steam, and a heat source at a temperature near about 260 ° C. (about 500 ° F.). Using is inefficient and leads to minimal amount of steam production. In a typical steam power generation system, low temperature exhaust (up to 260 ° C.) of the heat source exiting the boiler can be used to preheat the boiler feed water using a separate heat exchanger. However, only a limited amount of heat in the released air can be recovered, and this heat generally has a maximum temperature of 260 ° C. (500 ° F.), the discharge temperature of the heat source exhaust gas, and water. Is limited to a temperature difference of about 204 ° C. (about 400 ° F.) or higher due to its vapor pressure and temperature characteristics. Thus, using waste heat to preheat boiler feedwater increases the overall efficiency of the system and in some cases may increase efficiency by 10%.

  Some cogeneration systems and combined power generation cycle systems also incorporate an organic Rankine cycle (ORC) system in combination with a steam turbine system to add additional heat source cold exhaust stream as it exits the boiler. Envision obtaining power output. Methods that utilize an ORC cycle to generate useful power are known in the prior art. Exemplary methods are disclosed, for example, in US Pat. Nos. 5,570,579 and 5,664,414. These US patents are hereby incorporated by reference. These prior art systems use conventional ORC media such as positive pentane, isopentane, toluene, fluorinated hydrocarbons and other coolants. These conventional ORC media have pressure and temperature limits and cannot withstand high temperatures due to the self-ignition temperature and vapor pressure versus temperature characteristics of each media. For example, prior art ORC systems that utilize a coolant or toluene are limited to operation using heated water because the ORC medium cannot absorb energy when the ORC medium is in the elevated temperature state. Other prior art ORC methods require ORC media in which vapor pressures near atmospheric pressure are effective. Other prior art systems are limited to a specific power output range, others require applying a fluid ORC medium to the heat exchanger for efficient operation. These limitations reduce the effectiveness and efficiency of their ORC media, thereby limiting the chances that they will be used and the useful energy output that can be obtained from them.

  In addition, the majority of energy is generated by using a closed loop system (i.e., a system in which a power generation medium such as water / steam is constantly recirculated), such as the system described above, Other methods of generating have been developed to utilize open loop power sources that require constant replenishment of the power generating medium. For example, where the light hydrocarbon pressure supplied to the petrochemical plant or gas pipeline must be reduced before the light hydrocarbon is sent to the consumer, the gas pressure in the valve is reduced (in this case, the energy Rather than being recovered), it is known to produce useful power by expanding high pressure gas in an expansion turbine operating an electrical power generator, pump or compressor. Examples of this type of technology are provided in US Pat. Nos. 4,711,093 and 4,677,827. These US patents are hereby incorporated by reference. These technology systems are open loop systems that require constant replenishment of the power generation medium and depend on the pressure level of the process design.

  In a first embodiment, the present invention provides an energy generation method. The method supplies a working fluid; increases the pressure of the working fluid; divides the working fluid into a plurality of flows including at least a first flow and a second flow; a first amount of thermal energy from the energy source to the first flow. Then transferring a second amount of thermal energy from the first stream to the second stream; extracting a first useful energy quantity from the first stream; extracting a second useful energy quantity from the second stream; Combining the stream with the second stream; reducing the first and second streams to a minimum pressure; The minimum pressure is approximately or less than the vapor pressure at the ambient temperature of the working fluid.

  In this embodiment, the step of transferring the second amount of thermal energy from the first stream to the second stream includes the step of transferring the second amount of thermal energy from the first stream to the second stream before joining the first stream to the second stream. Transferring the second portion of the second amount of thermal energy from the first flow to the second flow after the first flow is merged with the second flow. Also in this embodiment, the step of transferring the first portion of the second thermal energy amount from the first flow to the second flow may be performed after the step of extracting the first useful energy amount from the first flow. . Still further, in this embodiment, the sum of the first useful energy amount and the second useful energy amount may be equal to at least about 20% of the first thermal energy amount.

  In this and other embodiments of the invention, the working fluid may be selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof. The minimum pressure may be from about 172.37 absolute KPa to about 2068.43 absolute kPa (about 25 psia to about 300 psia) and the ambient temperature is about -45.5 ° C to about 71.1 ° C (about -50 ° F to about 160 ° F). The energy source may be selected from the group consisting of fossil fuel energy, nuclear energy, solar energy, geothermal energy, waste heat energy, hydrogen, and combinations thereof. In this and other embodiments, the working fluid may be pumped to about 2068.43 absolute KPa to about 6894.76 absolute KPa (about 300 psia to about 1000 psia).

  In another embodiment, the present invention provides an energy generating device. The apparatus includes a plurality of fluid conduits including at least a first fluid conduit, a second fluid conduit, and a combined fluid conduit that can include a working fluid therein; operatively attached to the plurality of fluid conduits and the working fluid An energy source; a first heat exchanger operatively attached to the first fluid conduit and transferring a first amount of thermal energy from the energy source to the working fluid in the first fluid conduit. And operatively mounted downstream of the first heat exchanger with respect to the first fluid conduit and attached to the first fluid conduit and the second fluid conduit, from the working fluid in the first fluid conduit A second heat exchanger for transferring a second amount of thermal energy to the working fluid in a second fluid conduit; operably attached to the first fluid conduit and first from the working fluid in the first fluid conduit; Useful heat A first fluid expander for extracting an amount of energy; a second fluid expander operably attached to the second fluid conduit and extracting a second useful thermal energy amount from the working fluid in the second fluid conduit; Operatively attached to at least one of the plurality of fluid conduits to reduce the working fluid pressure to a minimum pressure that is approximately equal to or less than the vapor pressure at ambient temperature of the working fluid And a cooler. The first fluid conduit and the second fluid conduit are combined at a junction to form the combined fluid conduit.

  In this second embodiment, the second heat exchanger is disposed between the first fluid expander and the confluence with respect to the first fluid conduit and is operably operable with the first fluid conduit and the first fluid conduit. A primary second heat exchanger attached to a two-fluid conduit and transferring a first portion of the second amount of thermal energy from the working fluid in the first fluid conduit to the working fluid in the second fluid conduit; Operatively disposed between the junction and the pump with respect to the coupling fluid conduit and operatively attached to the second fluid conduit and the coupling fluid conduit, and a second portion of the second amount of thermal energy within the coupling fluid conduit A secondary second heat exchanger that transfers from the working fluid to the working fluid in the second fluid conduit. The second heat exchanger may be disposed after the first fluid expander with respect to the first fluid conduit. In this embodiment, the sum of the first useful energy amount and the second useful energy amount may be equal to at least about 20% of the first thermal energy amount.

  In yet another embodiment, the present invention is an energy conversion method for converting heat into useful energy comprising: providing a liquid combined fluid stream; pressurizing the combined fluid stream; Splitting into a fluid stream and a secondary fluid stream; applying heat energy from a heat source to the primary fluid stream to evaporate; expanding the evaporated primary fluid stream to produce a first amount of useful energy; evaporating and expanding Transferring heat from the generated primary fluid stream to superheat the evaporated secondary fluid stream; expanding the evaporated second fluid stream to produce a second amount of useful energy; evaporating and expanding Mixing a primary fluid stream with the evaporated and expanded secondary fluid stream to form a combined fluid stream; transferring heat from the combined fluid stream to evaporate the secondary fluid stream; To condense into a liquid state; Providing an energy conversion method comprising Nde.

  In this embodiment, the step of transferring heat from the combined fluid stream to evaporate the secondary fluid stream also maintains the pressure of the combined fluid stream above the vapor pressure of the fluid. Further, it may be included.

  In yet another embodiment, the present invention provides an apparatus for converting heat into useful energy. The apparatus includes a coupling fluid conduit carrying a fluid stream; a pump operably attached to the coupling fluid conduit; and operatively attached to the coupling fluid conduit downstream of the pump and operatively primary. A flow separator attached to the fluid conduit and the secondary fluid conduit; a first heat exchanger operably attached to the primary fluid conduit downstream of the flow separator and operably attached to a heat source; A first expander operably attached to the primary fluid conduit downstream of the first heat exchanger; and a primary fluid conduit operably attached and operable downstream of the first expander; A second heat exchanger attached to the secondary fluid conduit; and operably attached to the secondary fluid conduit downstream of the fluid separator; and A third heat exchanger operably attached to the coupling fluid conduit; and a second expander operably attached to the secondary fluid conduit downstream of the second heat exchanger; A flow mixer attached to a fluid conduit, to the primary fluid conduit downstream of the second heat exchanger, and to a secondary fluid conduit downstream of the second expander; operably the flow mixer; A cooler attached to the coupling fluid conduit between the pumps. The third heat exchanger is disposed between the flow mixer and the cooler with respect to the combined fluid conduit, and the second heat exchanger is configured with the third heat exchanger and the second with respect to the secondary fluid conduit. Arranged between expanders.

  In yet another embodiment, the present invention provides an efficiency improvement method for improving the efficiency of a power system having an energy source and a cooling system. The efficiency improvement method transfers a first amount of thermal energy from a cooling system to a first loop of a cascading closed loop cycle system; extracts a first useful energy amount from the first loop; and a cascading closed loop cycle from the energy source. Transferring a second amount of thermal energy to a second loop of the system; extracting a second amount of useful energy from the second loop.

  In this embodiment, the efficiency improvement method transfers a third amount of thermal energy from the second loop to a third loop of a cascading closed loop cycle system; and extracts a third useful energy amount from the third loop. A step may be further included. In this embodiment, the power system may generate a fourth useful energy amount by receiving a fourth heat energy amount from the energy source. The sum of the first useful energy amount, the second useful energy amount, the third useful energy amount, and the fourth useful energy amount may be equal to at least about 30% of the fourth thermal energy amount.

  In another embodiment, the present invention provides a method for improving the efficiency of a power system having an energy source and a cooling system. The efficiency improvement method provides a working fluid; increases the pressure of the working fluid; divides the working fluid into a plurality of flows including at least a first flow and a second flow; from the cooling system to the first Transferring a first amount of thermal energy to the stream; extracting a first amount of useful energy from the first stream; transferring a second amount of thermal energy from the energy source to a second stream; Extracting an amount of energy; cooling the working fluid to a minimum pressure that is approximately equal to or less than a vapor pressure at an ambient temperature of the working fluid. Also in this embodiment, extracting the second useful energy amount from the second flow extracts a part of the second useful energy amount from the primary second flow; and extracting the second useful energy amount from the secondary second flow; 2 extracting a part of the useful energy amount. In this embodiment, the power system may be a steam power generation system.

  In yet another embodiment, the present invention provides an energy generation method. In this embodiment, the method of generating energy supplies a first working fluid; increases the pressure of the first working fluid; transfers a first amount of thermal energy from an energy source to the first working fluid; Extracting a first amount of useful energy from the first working fluid; supplying a second working fluid; increasing a pressure of the second working fluid; a plurality of the second working fluid including at least a first flow and a second flow A second thermal energy amount is transferred from the first working fluid to the first flow; a second useful energy amount is extracted from the first flow; from the energy source to the second flow Transferring a third amount of thermal energy; extracting a third amount of useful energy from the second stream; and reducing the first heat energy to a minimum pressure that is approximately equal to or less than a vapor pressure at an ambient temperature of the second working fluid. 2 cooling the working fluid. In this embodiment, the second flow includes a primary second flow and a secondary second flow, and transferring a third amount of thermal energy from the energy source to the second flow is from the energy source to the primary flow. Transferring the third thermal energy amount to two streams; transferring the third thermal energy amount from the primary second stream to the secondary second stream. Further, in this embodiment, extracting the third useful energy amount from the second flow extracts a first portion of the third useful energy amount from the primary second flow; Extracting a second portion of the third useful energy amount. In this embodiment, the first working fluid may be water.

  In yet another embodiment, the present invention provides a method for improving the efficiency of a power system having an energy source and a cooling system. The efficiency improvement method of this embodiment provides a working fluid; increases the pressure of the working fluid; divides the working fluid into a first flow, a second flow and a third flow; A first amount of thermal energy is transferred to the first stream; a first useful energy amount is extracted from the first stream; a second amount of thermal energy is transferred from the energy source to the second stream; from the second stream; Extracting a second useful energy quantity; transferring a third thermal energy quantity from the second stream to the third stream; extracting a third useful energy quantity from the third stream; steam at an ambient temperature of the working fluid; Cooling the working fluid to a minimum pressure that is approximately equal to or less than the vapor pressure. In this embodiment, the step of transferring the second amount of thermal energy from the energy source to the second stream includes transferring a first portion of the second amount of thermal energy from the energy source to the second stream in the first heat exchanger, The second heat exchanger may include transferring a second portion of the second amount of thermal energy from the energy source to the second stream. In this embodiment, extracting the first useful energy amount from the first flow also includes expanding the first flow in a first expander; and extracting the second useful energy amount from the second flow. Extracting includes expanding the second stream in a second expander; extracting a third amount of useful energy from the third stream includes expanding the third stream in a third expander. It is good as well. In this embodiment, the power system may be a steam power generation system.

  In yet another embodiment, the present invention provides a supplemental energy generator that generates supplemental energy from a power system having an energy source and a cooling system. The supplemental energy generating device of this embodiment includes a plurality of fluid conduits including at least a first fluid conduit, a second fluid conduit, and a combined fluid conduit capable of containing a working fluid therein; operating on the plurality of fluid conduits One or more pumps operably attached to pressurize the working fluid; and operably attached to the first fluid conduit to transfer a first amount of thermal energy from the cooling system to the working fluid in the first fluid conduit. A first heat exchanger that operably attaches to the first fluid conduit and extracts a first amount of useful energy from the working fluid in the first fluid conduit; operably second A second heat exchanger attached to the fluid conduit and transferring a second amount of thermal energy from the energy source to the working fluid in the second fluid conduit; operably attached to the second fluid conduit A second fluid expander for extracting a second amount of useful energy from the working fluid in the second fluid conduit; and a cooler operably attached to at least one of the plurality of fluid conduits; A cooler that reduces the pressure of the fluid to a minimum pressure that is approximately equal to or less than the vapor pressure at ambient temperature of the working fluid. The first fluid conduit and the second fluid conduit are combined at one or more junctions to form a combined fluid conduit. In this embodiment, the plurality of fluid conduits further include a third fluid conduit, and a supplemental energy generator is operably attached to the second fluid conduit and the third fluid conduit, A third heat exchanger for transferring a third amount of thermal energy from the working fluid to the working fluid in the third fluid conduit; operably attached to the third fluid conduit and in the third fluid conduit And a third fluid expander that extracts a third useful energy amount from the working fluid, and the third heat exchanger is disposed after the second fluid expander with respect to the second fluid conduit. It is good also as setting up. In this embodiment, the second heat exchanger may be two heat exchangers. In this embodiment, the power system may further receive a fourth thermal energy from the energy source to generate a fourth useful energy amount. The sum of the first useful energy amount, the second useful energy amount, the third useful energy amount, and the fourth useful energy amount may be equal to at least about 30% of the fourth thermal energy amount.

  In yet another embodiment, the present invention provides an energy conversion device that converts thermal energy into useful energy. The energy conversion device includes a primary power system and a secondary power device, the primary power system; an energy source; a primary fluid conduit that can include a primary working fluid therein; and operably attached to the primary fluid conduit. A primary fluid pump that pressurizes the primary working fluid and is operatively attached to the primary fluid conduit and transfers a first amount of thermal energy from the energy source to the primary fluid contained within the primary fluid conduit. A secondary power system comprising: an exchanger; and a primary fluid expander operably attached to the primary fluid conduit for extracting a first useful amount of energy from the primary working fluid in the primary fluid conduit. Is a secondary fluid conduit system that includes a first fluid loop, a second fluid loop, and a third fluid loop, wherein the secondary fluid conduit system can include a secondary working fluid therein A body conduit system; one or more secondary fluid pumps operatively attached to the secondary fluid conduit and pressurizing the secondary working fluid; and with respect to the primary fluid conduit, the primary fluid expander and the primary fluid pump A first heat exchanger disposed between and operatively attached to the first fluid loop and the primary fluid conduit, from the primary fluid in the primary working fluid conduit to the first fluid loop. A first heat exchanger for transferring a second amount of thermal energy to a secondary working fluid; and a second useful energy amount from the secondary working fluid in the first fluid loop operably attached to the first fluid loop; A first fluid expander for extraction; operably attached to the second fluid loop and transferring a third amount of thermal energy from the energy source in the second fluid loop to the secondary working fluid; A second heat exchanger; operably attached to the second fluid loop and extracting a third amount of useful energy from the secondary working fluid in the second fluid loop; and with respect to the second fluid loop A third heat exchanger disposed after the second fluid expander and operably attached to the second fluid loop and the third fluid loop, wherein the secondary working fluid in the second fluid loop A third heat exchanger for transferring a fourth amount of thermal energy from the second working fluid in the third fluid loop to the second working fluid; operably attached to the third fluid loop and in the second fluid loop A third fluid expander for extracting a fourth amount of useful energy from the secondary working fluid; a cooler operably attached to the secondary fluid conduit, the vapor pressure at ambient temperature of the secondary working fluid A cooler that reduces the pressure of the secondary working fluid to a minimum pressure that is approximately equal to or less than the vapor pressure. In this embodiment, the primary working fluid may be water. Also in this embodiment, the sum of the first useful energy amount, the second useful energy amount, the third useful energy amount, and the fourth useful energy amount may be equal to at least about 30% of the first thermal energy amount.

  The present invention can be more easily interpreted with reference to the accompanying drawings.

  Developing energy sources more efficiently is of paramount importance as energy sources have been exhausted and the pollution resulting from the burning of fossil fuels continues to harm the environment. The cascading closed loop cycle of the present invention provides a closed loop power generation system that can be used as a primary power source. Along with CCLC, efficiency improvements reduce the amount of energy loss to overcome the heat of vaporization of the power generation medium, and more effectively capture heat from available heat sources and convert this heat into useful energy. Provided by. The super cascading closed loop cycle (super CCLC or super CCLC) of the present invention generates power by generating useful energy from the heat lost in the process of generating power using a steam turbine or other conventional power system. To increase efficiency, a secondary power source is provided that can be used in conjunction with conventional power systems. In super CCLC, the efficiency improvement comes from recovering energy from two waste heat sources as described in the background section of the invention. The first source is the recovery of waste heat leaving the boiler and the second source is the recovery of waste heat released during the condensation process.

  It can be shown thermodynamically that the organic Rankine cycle (ORC) can be used to convert heat energy into mechanical energy particularly well. A super CCLC system is an ORC designed to convert heat lost in the process of generating steam turbine power. US Patent Application No. 10 / 199,257, filed July 22, 2002, the contents of which are incorporated herein by reference, is a propane like fluid medium in a cascading closed loop cycle (CCLC). A method is described that utilizes an ORC cycle to generate useful power using propylene or an equivalent or similar light hydrocarbon medium. As used herein (including herein and in the claims), the term “fluid” means a material in a liquid, gaseous and / or vapor state. In general, materials described herein as “fluid” always remain in a liquid, gas, and / or vapor state, but it is understood that such fluid may solidify under some circumstances. Wax does not solidify during the operation of the invention described herein. The present invention further contemplates the use of multiple integrated CCLC systems that simultaneously recover waste heat from a steam boiler (or other heat source) and waste heat resulting from a steam condensation process (or similar process).

  Various preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

  In one embodiment, the present invention utilizes a unique configuration and method for operating a cascading closed loop cycle (CCLC) to extract additional efficiency from an energy source. Cascading closed loop cycle (CCLC) is a hermetically sealed closed loop process. As shown in FIG. 1, the CCLC 100 has a primary fluid stream A, a secondary fluid stream B, and a combined fluid stream C. The combined fluid stream C includes essentially the entire supply of power generation medium, which preferably includes a light hydrocarbon material, more preferably propylene, propane or a combination of these materials. Primary fluid stream A and secondary fluid stream B include a portion of the combined fluid stream C divided by the flow separator 104.

CCLC 100 begins with a high pressure pump 102 that raises the liquid combined fluid stream C to the required initial pressure. (Because this cycle is a closed-loop system in which the cycle is constantly recirculated, technically there is actually no “starting” point of the system, and this starting point is arbitrarily and only chosen for clarity of explanation. It was those.) in this regard, coupling fluid stream C has here certain physical properties that are correlated defined as a state C 1 (pressure, temperature and mass flow rate). State C 1, other conditions of the fluid flow at various points in the process are described in detail elsewhere herein. The combined fluid stream C is then split by the flow separator 104 into a primary fluid stream A in state A 1 and a secondary fluid stream B in state B 1 . The various states described here are approximate, and some parts of the device are tasked to have only one state, but in that state, friction, local heating or cooling, fluid motion, etc. Temperature, pressure, etc. may change.

The primary fluid stream A is sent to the primary indirect heat exchanger 106, where the primary fluid stream A is exposed to a heat source or energy source and evaporates. The heat source or energy source can be any usable heat source such as fossil fuel or hydrogen combustion, nuclear reaction, solar heat, fuel cell, geothermal energy, waste heat, etc. Further, the heat source can be residual heat resulting from other industrial operations. Non-limiting examples of such heat sources are heat from smelters, chemical processing and purification systems, drying systems, kilns and ovens, boilers, heaters, furnaces, gas turbines, and the like. The heat is transferred to the primary fluid stream is identified as Q 106. In FIG. 1, the heat source is an air stream (combustion exhaust gas) heated by burning fossil fuel, and is generally indicated by the letter H. Flue gas H flows into the primary indirect heat exchanger 106 in a state Hl, exits therefrom while H 2. The flue gas H exiting the primary indirect heat exchanger 106 may be released to the atmosphere via a flue or the like. Of course, any type of heat exchange device can be used as the primary indirect heat exchanger 106, i.e., other heat exchangers, coolers, condensers, etc. as described herein can be used. The selection of a specific heat exchange device may depend on the type of heat source used. For example, in various embodiments, the heat exchange device can be a heat exchanger that changes from air to liquid, a water tube boiler, a shell (smoke tube boiler), or the like. The selection and use of such devices is known in the prior art.

Once evaporated, the primary fluid flow A is in the state A 2. Primary fluid stream is then primary expansion turbine 108 to reach state A 3 (preferably turbo expander) to generate a first supply energy W 108 useful with inflated within. Once it is inflated, the primary fluid flow A is sent to a secondary indirect heat exchanger 110, where the primary fluid flow A is heat to the secondary fluid stream B, exits at state A 4. Heat transfer between the primary fluid flow and secondary fluid flow is identified as Q 110. Finally, the primary fluid stream A is discharged to the flow mixer 112 where it is combined with the secondary fluid stream B. Bound primary and secondary fluid flow will bind the fluid flow C of the state C 2.

The secondary indirect heat exchanger 110 uses the heat that remains in the evaporated fluid of the primary fluid stream A after the evaporated fluid of the primary fluid stream A exits the primary expansion turbine 108. Heat stream B. Secondary fluid stream B enters the state B2 secondary indirect heat exchanger 110 and exits in a state B 3. The secondary fluid stream B having state B 3 is then directed to the secondary expansion turbine 116 to generate a second useful energy supply W 116 . The secondary fluid flow changes to state B 4 as it passes through secondary expansion turbine 116. The secondary fluid stream B is then merged into the primary fluid stream A in the mixer 112 to form a combined fluid stream C as previously described. The combined fluid stream C is then directed to the tertiary indirect heat exchanger 114 where the heat of the combined fluid stream C is transferred to the secondary fluid stream B, causing the secondary fluid B to change from state B 1 to state B 2. And the combined fluid flow is changed from state C 2 to state C 3 . The heat is transferred from the coupling fluid flow into the secondary fluid stream is identified as Q 114. Coupling fluid flow C is directed to the condenser (condenser) 118 after exiting the tertiary indirect heat exchanger 114, where the coupling fluid flow C is condensed to a liquid having a condition C 4. The condenser 118 extracts the heat quantity Q 114 from the combined fluid stream C and is also absorbed by a suitable refrigerant such as water or air. Once the fluid in combined fluid stream C has been condensed and returned to a liquid state, it is directed to high pressure pump 102 to initiate a new cycle. The pump 102 requires a power quantity P 102 that pressurizes the combined fluid stream C to the required state C1.

  Primary expansion turbine 108 and secondary expansion turbine 116 may be connected in series or in parallel to an energy generator that uses speed change means to produce mechanical or electrical energy. Alternatively, one or both expansion turbines may be attached to a compressor, pump, power generator, or other device that can be used to provide additional useful energy or work. Moreover, the CCLC of FIG. 1 may be modified to include additional heat exchangers, condensers, pumps or expansion turbines within the basic idea. Pumps, flow separators, heat exchangers, expansion turbines, turboexpanders, condensers and the like, and alternative devices are known in the prior art. Moreover, techniques and devices for attaching these various devices are also known in the prior art.

The cascading closed loop cycle of the present invention is further described with respect to FIG. FIG. 2 is a Mollier diagram (ie, pressure versus entropy diagram) of the CCLC power generation cycle. In FIG. 2, the vertical axis 250 represents pressure, the horizontal axis 252 represents entropy (ie, BTU per pound), and a number of isotherms 254 along with a working fluid saturation curve 256. Desirably, the working fluid in the embodiment of FIG. 2 is propane. Also in FIG. 2, the combined fluid flow C of FIG. 1 is drawn with a double line C, the primary fluid flow A is drawn with a single line A, and the secondary fluid flow B is drawn with a broken line B. For ease of viewing, the line (s) representing the fluid flow are separated so that they can be clearly distinguished from each other at certain locations. Also for clarity, each point in FIG. 2 represents the temperature of one or more states described above with respect to FIG. 1 (e.g., state C 1 , state C 2 , state A 1 , state B 1, etc.). And symbolizes pressure. Although single points are used for ease of viewing, those skilled in the art will recognize that the various states represented by each of these points may actually be at a distance from each other. I will.

The CCLC of FIG. 2 begins at point 201 (corresponding to states A 1 , B 1 , and C 1 ) for the purposes of this discussion. At this point, the combined fluid stream C is pressurized by the high pressure pump 102 and split into separate streams. States C 1 , A 1 and B 1 are almost the same, some differences are due to pump loss, friction, etc. First fluid stream A and second fluid stream B are processed along separate paths, starting at point 201. The first fluid stream A is heated to point 202 (state A2) at a substantially constant pressure by absorbing heat from the flue gas H in the primary indirect heat exchanger 106. The first fluid stream A is then expanded in the primary expansion turbine 108 until reaching point 203 (state A 3 ) along an essentially constant entropy line (not shown). Next, the first fluid stream A is radiated to the secondary fluid stream B in the secondary indirect heat exchanger 110, thereby being cooled to a point 204 (state A 4 ) under a substantially constant pressure. At this point, the primary fluid stream A is mixed with the secondary fluid stream B and once again becomes the combined fluid stream C.

The secondary fluid stream B also begins at point 201 (representing state B 1 ) and absorbs heat from the combined fluid stream C in the tertiary indirect heat exchanger 114, resulting in point 205 (state B 2 under nearly constant pressure). ) Until heated. The secondary fluid stream B is then heated to point 206 (state B 3 ) under a substantially constant pressure by absorbing heat from the primary fluid stream A in the secondary indirect heat exchanger 110. Secondary fluid stream B then expands in secondary expansion turbine 116 along an essentially constant entropy line (not shown) until point 204 (state B 4 ) is reached, at which point primary fluid flow B Mixed with stream A to form combined fluid stream C.

When the combined fluid stream C is coupled at one end, it radiates heat to the secondary fluid stream B in the third indirect heat exchanger 114 as described above, thereby cooling to the point 207 (state C3) under a substantially constant pressure. It is. The combined fluid stream C is further cooled by the condenser 118 until point 208 (state C 4 ) is reached. Again, the cooling from point 207 to point 208 occurs under a relatively constant pressure. After the combined fluid stream is cooled to a liquid state, the high pressure pump 102 pumps it to point 201 (state C 1 ) at a relatively constant temperature and a new cycle begins.

By carefully selecting and controlling various states of the fluid flow, the present invention can be used to provide very efficient power generation as compared to conventional steam power generation systems. Table 1 below provides approximations for the preferred embodiment of the various states identified in FIG. 1 and other data related to the operation of the preferred embodiment. The working fluid in Table 1 is propane. The data shown in Table 1 and elsewhere in the specification represent preferred embodiments of the invention, but these values may be changed or specified operating systems without departing from the scope and technical spirit of the invention. Or it is understood that the operating requirements may be adapted.

The efficiency of the CCLC embodiment presented in Table 1 is calculated by dividing the net power (W 108 + W 116 -P 102) by the heat entering the system from the heat source (Q 106 ). It has been found that the efficiency of the present invention far exceeds that of conventional power systems. This greater efficiency can be used to increase power output or reduce resource consumption, and the greater efficiency can be easily utilized to reduce emissions (contaminants and higher temperatures). It can be provided in two forms: reduction of both heat pollution caused by exhaust and increased resource protection. There are many other benefits of this efficiency improvement that cannot be described. However, those benefits will be readily understood by those skilled in the art. In preferred embodiments, the efficiency of CCLC is at least about 17%, more desirably at least about 20%. Moreover, as can be seen in Table 1, the efficiency in one preferred embodiment of the present invention was found to be approximately 22%. This efficiency is significantly greater than that obtained by relatively expensive and complex prior art steam power generation systems. An example of such a prior art steam power generation system is shown in FIG.

In the prior art steam system 300 of FIG. Pump 202 pressurizes the water fluid flow to state S 1. The pump 202 requires a certain amount of power P 202 to pressurize water. Pressurized water is then vaporized into steam having a condition S 2 is heated in an indirect heat exchanger 204 by flue gas 220 other conventional heat sources. Flue gas 220 enters the indirect heat exchanger 204 in the state H 1, exit at state H 2, to transmit the heat Q 204 in water fluid stream S. Vapor is then directed to the expansion turbine 206, where, being inflated up to state S 3, to produce useful energy supply W 206. Vapor is cooled in a condenser 208 or other type of cooler to a liquid with a state S 4. During this cooling process, the amount of heat Q 208 must be removed from the vapor in order to condense it into a liquid. Table 2 shows typical optimized approximations for various states and other variables of the prior art steam system 300 of FIG.

As shown in Table 2, the prior art steam cycle receives the same heat input as the CCLC described in FIGS. Both systems receive a flue gas supply of 399 ° C. (750 ° F.) and 170.3 absolute KPa (24.7 psia) as a heat source at a rate of 378,205 Kg / h (833,300 lb / h). However, the prior art steam cycle has an efficiency of 16.0% ((W 206 -P 102 ) / Q 204 ). In comparison, CCLC is 21.9% efficient, so CCLC provides an efficiency that is about 33% higher than prior art steam systems. This higher efficiency is provided despite the additional pumping energy required by CCLC systems with slightly compressible liquid propane or equivalent light hydrocarbons.

  The present invention can provide this significant efficiency increase due in part to operating using propane or other light hydrocarbons rather than water as the working fluid. Propane has been found to have the property of providing many advantages over water when used in a power generation cycle. In any power generation cycle, the working fluid (usually water) is pumped when liquid, heated and vaporized, further heated to give steam great energy and expand to obtain useful energy ( Reduced pressure), cooled, liquefied and pumped to the cycle. As noted elsewhere in the specification, the amount of energy required to change a fluid from a liquid to a gas is essentially lost without being converted to useful energy. Propane advantageously has a relatively low heat of vaporization (about 1/7 of water) and requires less energy to convert liquid propane to gaseous propane. This saves considerable energy compared to prior art steam-based power systems.

  The present invention also has other features that contribute to obtaining relatively high efficiency. For example, it has been discovered that by maintaining propane at a minimum pressure of about 1379 absolute KPa (about 200 psia), propane can actually be used in a high temperature power generation system. This pressure is the approximate pressure at which propane will condense at room temperature (ie, the vapor pressure of propane). By keeping the minimum pressure below the vapor pressure of the working fluid, the system can be operated in typical climatic conditions without requiring active cooling (i.e. refrigeration) to condense the working fluid into a liquid. it can. In practice, for a given ambient temperature, it may be sufficient to make the minimum pressure approximately the vapor pressure of the working fluid. As will be apparent to those skilled in the art, some variation in minimum pressure may be allowed to maximize the overall efficiency of the system in response to anticipated or unexpected variations in ambient temperature or for other reasons. Good. The maximum pressure of propane is also desirably adjusted. Varying the pressure of propane exiting the pump can also optimize the expansion ratio of the turboexpander with respect to the available energy from the heat source and the work required to pump the fluid to a certain pressure. Good. In a preferred embodiment, the maximum pressure of propane is from about 206.43 absolute Kpa to about 6894.76 absolute Kpa (about 300 psia to about 1000 psia), although other pressures may be used depending on the circumstances. One skilled in the art will be able to optimize the propane pressure to achieve this or other purposes.

  Another advantageous property of propane given by its lower heat of vaporization than water of propane is that propane can be heated from 37.8 ° C to 537.8 ° C (100 ° F to 53 ° C to produce more surplus energy for expansion in the turbine. It can be heated to a temperature range of 1000 ° F. (ie more heat can be recovered). In fact, propane can recover the available heat at temperatures close to standard ambient temperature, allowing CCLC to be used to generate power from a low temperature heat source. As such, the CCLC of the present invention can be used in place of a steam system or other high temperature system or in place of a low temperature ORC system.

  The high efficiency of the present invention is also partly due to the unique cascading turbine configuration in which successive turbines are operated by “cascading” the energy obtained from the heat source from one fluid stream to the next. Provided to. Furthermore, the high efficiency of the present invention is provided in part by a unique tertiary indirect heat exchanger configuration that preheats the secondary fluid stream, giving a greater efficiency increase.

  CCLC provides additional performance advantages over prior art steam systems in addition to increased efficiency. For example, the efficiency of CCLC is not adversely affected by changes in the pressure of the heat source (when the heat source is at a temperature sufficient to evaporate propane) or changes in the altitude position of the pressure. This is because the working fluid is sealed in its own environment. Of course, the heat source that operates the CCLC may be adversely affected by the altitude, leading to a corresponding decrease in power output, but the efficiency of the CCLC will remain substantially the same.

  Furthermore, the power output of the CCLC increases as the ambient temperature decreases. This is because the pressure at which condensation begins decreases again as the ambient temperature decreases. As such, when operating in a lower temperature environment, the lower limit of propane pressure can be lowered and the residual pressure of propane at the same level can be maintained. As this is done, the pressure differential of propane increases and the expansion ratio of the turboexpander can be increased using the amount of additional energy available over this wider pressure range. This advantage may also be realized by using a condensing medium that is cooler than the ambient air. For example, if cold water (eg, 4.4 ° C. (40 ° F.)) is used as a refrigerant to condense propane into a liquid, a turbo with low back pressure takes advantage of the fact that propane condenses at the corresponding low pressure. It is good also as changing a system to operate an expander. In contrast, prior art steam systems are largely independent of temperature. This feature makes it more desirable to use CCLC systems in colder climates. Although it is expected that the present invention will be efficient when used without a wide range of ambient temperature changes, the minimum pressure of propane (or other media) is less than or equal to the vapor pressure at a particular ambient temperature of the power generation facility. It may be desirable to change to Desirably, the ambient temperature is between about −45.5 ° C. and about 71.1 ° C. (about −50 ° F. to about 160 ° F.), and the minimum pressure is about 172.37 absolute KPa to about 2068.43 absolute KPa (about 25 psia to about 300 psia). It is adjustable. Of course, these range limitations are not limiting and the present invention can be easily made to have pressures below or above these ranges utilizing the specific operating conditions expected for the system. Can be changed.

  The CCLC of the present invention still offers other advantages. For example, the CCLC system of the present invention can be built at the same cost as or lower than the cost of a conventional steam power generation system. This is because propane can be expanded by using a relatively inexpensive turbo expander rather than an expensive steam turbine. However, in the unlikely event that CCLC construction costs exceed that of conventional power systems, the higher efficiency of CCLC also recaptures any excess manufacturing costs due to lower operating costs and / or higher power output. Can do. Typical turboexpanders that may be used with the present invention are GE Power Systems, ABB Alstom, Atlas Copco, Mafi Trench, GHH Borsig Including those commercially available from (GHH-Borsig). These turbo expanders may be of any design, and in one embodiment, the turbo expander is a centrifugal type expander.

CCLC also provides a number of operational benefits. Conventional steam systems require periodic cleaning and chemical treatment to prevent or reduce scale buildup caused by minerals in the water. The steam system can be operated such that the steam is at a vacuum (low pressure) compared to the atmosphere, in which case air and other contaminants are allowed to enter the system, reducing efficiency. In a typical steam system, water must be drained to remove contaminants and replaced at regular intervals to maintain the system. This results in a large consumption of valuable water resources. In contrast, CCLC systems are sealed for relatively pure propane and require little cleaning or maintenance. Furthermore, CCLC CCLC is steam system (i.e., the state temperature of S 3) than the low waste heat discharge temperature (i.e., the state temperature of C 3) operating at, this is by natural water sources such as lakes and rivers Can be cooled and the generation of thermal contamination is minimized. CCLC also operates globally above atmospheric pressure, eliminating the possibility of contaminants entering the system and eliminating the need to consume water resources to maintain the system. CCLCs also operate in the same pressure range as conventional systems and can be made using conventional construction techniques and piping techniques.

  In another embodiment, the present invention can be used in connection with other heat sources in conventional steam systems. In this embodiment, the present invention includes a super cascading closed loop cycle (super CCLC) that converts waste heat into usable power. In one embodiment, this super CCLC system converts waste heat from boiler exhaust and waste heat from the condensation process into useful output as long as the temperature of these heat sources is high enough to evaporate propane. Purify power in cascading expansion turbines using propane or equivalent light hydrocarbon media. The present invention comprises one or more indirect heat exchangers, expansion turbines, flow mixers, condensing units, pumps, and flow separators that operate in conjunction with steam boilers and steam turbines. If the steam turbine is a vacuum design, the steam turbine is desirably modified to operate as a back pressure steam turbine with a back pressure controlled to about 172.4 absolute KPa (about 25 absolute psi), and the vacuum condensing system is Modified, eliminated or bypassed. Instead of a vacuum condenser to absorb the heat of vapor evaporation when the steam condenses into water, a heat exchanger that vaporizes propane will be installed.

  Air exhaust from the steam boiler is directed to an air propane (transfers heat from air to propane) heat exchanger, and exhaust from the steam turbine is directed to a steam propane (transfers heat from steam to propane) condenser . Waste heat exiting the steam boiler evaporates the pressurized propane using one or more pumps. The heat from the steam turbine exhaust evaporates the pressurized liquid propane stream using one or more pumps. The pressurized liquid propane stream evaporates in a plurality of indirect heat exchangers and expands in a plurality of turboexpanders. The exhaust heat from the turboexpander can be used to recover additional heat using a heat exchanger that transfers heat from propane to propane. These turbo expanders can be connected in series or in parallel to a plurality of power generators such as a generator, a pump, or a compressor using a transmission means. Power generation devices such as generators and devices used to attach these devices to turbo expanders, turbines, etc. are well known in the art.

  One embodiment of a super CCLC system is schematically illustrated in FIG. The super CCLC system 400 of FIG. 4 includes a vapor loop indicated by a double line and indicated by the letter S, and a multi-loop CCLC system indicated by a single line and indicated by the letters A through E. Although the super CCLC 400 of FIG. 4 is shown operating with respect to the steam loop, the super CCLC configuration of the present invention may also be operated with other types of power generation systems and heat sources. Indeed, various embodiments of super CCLC can be adapted to generate power from waste heat generated by various devices or systems including the heat sources described above or other heat sources. Moreover, the super-CCLC (or CCLC) embodiments of the present invention may be made to have a variety of different sizes and can provide significant power generation for the equipment. It may be large or may be made compact to act as a portable generator or to provide motive and / or auxiliary power to cars, trucks, trains, ships, aircraft, etc.

Operation of the steam loop of FIG. 4, the water pump 402 is started when the pressurized water flow S in state S 1. The water pump 402 requires a certain amount of power P 402 to pressurize the water stream S. The pressurized water stream S is a heat source in the boiler 404, such as flue gas (designated by the letter H), which enters the boiler in state H 1 and from there exits in state H 2 to state S 1 It is heated to a state S 2 from. The heat absorbed by the water stream S is designated here as Q 404 . The water stream S (which is superheated steam in state S 2 ) is then directed to the steam turbine 406 where the water stream S expands to state S 3 and generates a useful energy amount W 406 in the process. The water vapor S is then passed through a primary indirect heat exchanger 408 where heat Q 408 is transferred to the first loop stream C of the CCLC portion of the super CCLC system 400 (as described below). Desirably, heat transfer from the water stream S in the primary indirect heat exchanger 408 causes the water stream S to partially or completely condense from the gas phase (state S 3 ) to the liquid state S 4 . However, less heat transfer may be used. A supplemental condenser (not shown) can be provided after the primary indirect heat exchanger 408, and the water stream S can be further cooled to condense it more fully into a liquid. At this point, the water stream S is returned to the water pump 402 and a new cycle begins.

In one embodiment of the invention, the steam loop may be provided with a bypass system that allows it to be operated as a conventional steam power system. This is desirable, for example, when it is necessary to update, change or repair the CCLC portion of the system. In such an embodiment, one or more bypass valves 434 are provided to redirect the water stream through the condenser 408 'rather than the primary indirect heat exchanger 408, and then cycle toward the water pump 402. Can start again. In such an embodiment, the condenser 408 ′ extracts heat Q 408 ′ from the water and puts it in state S 4 ′ . As can be understood by one skilled in the art, of course, the route of the water stream S can be completely changed using other valves (not shown). This bypass route can also be used during the initial start of CCLC.

  The multi-loop CCLC portion of the super CCLC system 400 includes three loops emanating from the main combined fluid stream A or multiple combined streams. In a preferred embodiment, the working fluid comprising the fluid stream is propane or another light hydrocarbon. The main coupled fluid stream A is divided into a secondary coupled fluid stream B and a first loop stream C. The secondary combined fluid stream B is further divided into a second loop stream D and a third loop stream E. Useful energy is extracted from each of the first, second, and third loop streams (C, D, and E), and these streams recombine to form the main combined fluid stream A and begin a new process. . It is preferable to mix the loop flow fluids when they are combined, but the loop flows (or various flows of other embodiments of the invention) may instead always be isolated from each other. It will be appreciated that a separate pump is required for each fluid stream. The process by which the first, second and third loop flows produce useful energy is described in detail below.

The first loop stream C begins at state C1, and at that point, preferably the first loop stream C is liquid. The first loop stream C is compressed to state C 2 by the first high pressure pump 414. This pumping process requires the input of some work P4l4 . The first loop stream C is then directed to the first indirect heat exchanger 408 where it absorbs the amount of energy Q 408 and becomes steam in state C3. The first loop stream C then enters the first turboexpander 416, where it expands to state C4, driving the turboexpander 416 to produce useful energy W416 . The expanded first loop stream C is then mixed into the second and third loop streams (D, E) in a mixer 418. The second and third loop streams are each at the end of each cycle, as will be described below, where they form a main combined fluid stream A. As can be seen from FIG. 4, the first loop stream C receives mainly heat from the waste heat Q 408 from the steam loop S. This heat is usually lost completely without doing any useful work, but in super CCLC it is partially converted to useful energy, thus improving the efficiency of the unmodified system.

In the embodiment of FIG. 4, the secondary combined fluid stream B is pressurized from state B 1 to state B 2 by a second high pressure pump 420. This process requires the input of some work P 420 . After being pressurized, the secondary combined fluid stream B is divided into a second loop stream D and a third loop stream E by the second flow separator 422. Using the configuration shown, a single pump can be used to pressurize both the second and third loop streams. In other embodiments, the second and third loop streams may be pressurized separately, or before the first, second and third loop streams are divided into respective loop streams, the first, The second and third loop streams may be pressurized by a single pump or a set of pumps. Of course, other pump configurations may be used. Ideally, the pump configuration is selected to minimize the amount of work required to pump the fluid and reduce the total cost of the system. The pump configuration may be based on factors such as the required flow rate of the flow, the pump efficiency of various capacity pumps, and the cost of various capacity pumps. The pump configuration may be affected by the required pressure of the various loop flows (the flow having the same or similar required pressure pressurized by the same pump or a set of pumps). One skilled in the art will be able to perform this optimization for various embodiments of the present invention without undue experimentation.

Second loop flow D is desirably coming out from the flow separator 422 as the pressurized fluid starts with state D 1. As shown in FIG. 4, the second loop stream D is heated by the flue gas H (or other heat source) exiting the steam loop boiler 404. As previously noted, in prior art systems, the energy contained in the flue gas is usually lost without receiving virtually any benefit from the flue gas. However, in super CCLC, heat is transferred from the flue gas H to the second loop stream D using one or more heat exchangers. In the embodiment of FIG. 4, two heat exchangers are used. The second loop flow D is preheated in the first indirect heat exchanger 428, where it changes from state D 1 to the state D 2 because it absorbs the heat quantity Q 428 from the flue gas H. This heat transfer cools the state H 4 flue gas H from the condition H 3. The second loop flow D is further heated by the combustion exhaust gas H in the third indirect heat exchanger 430 where it exits in a state D 3 receives the heat Q 430. This heat exchanger change cools the combustion exhaust gas H from the state H 3 to the state H 2 . The second loop stream D is then directed to the second turboexpander 432 where it expands to state D 4 to produce useful energy W 432 . The expanded second loop stream D passes through the fourth indirect heat exchanger 424 where it transfers heat to the third loop stream E and is cooled from state D 4 to state D 5 . Finally, the second loop stream D is mixed in the flow mixer 418 with the first and third loop streams (C and E).

Third loop stream E exits from flow separator 422 in state E1. The third loop stream E passes through the fourth indirect heat exchanger 424 where it absorbs the heat quantity Q 424 from the second loop stream D. The heat exchange Utsuwa換do it by evaporating the third loop flow E to state E 2. Once evaporated, the third loop stream E is directed to the third turboexpander 426 where it expands to state E3 to produce useful energy W426. Finally, the third loop stream E is mixed with the first and second loop streams (C and D) by the flow mixer 418.

As shown in FIG. 4, the first, second, and third loop flows (C, D, and E) are combined in their respective states (states C 4 , D5, and E 3 ) to form a primary combined fluid flow A. Form. Primary coupling fluid flow A is homogenized as the state A 1. The primary combined fluid stream A is passed through the condenser 410 to release the quantity of heat Q 410 to a suitable refrigerant and change to state A 2 . State A 2 is a liquid state desirably facilitates pump pressure. Primary coupling fluid flow A is cooled by the condenser 410, and secondary coupling fluid flow B is the state B 1, it is divided into a first loop flow C is the state C 1. From here, the process begins anew. As previously noted, a variety of different pump configurations may be used with the present invention, and other flow separators may be used to supply flow to these different pump configurations.

  One or more turbo expanders 416, 426, 432 and steam turbine 406 may be connected in series or in parallel to a plurality of power generators such as a compressor using a generator, pump or speed changing means. Power generation devices such as generators and devices used to attach them to turbo expanders, turbines, etc. are well known in the art.

The super CCLC process will now be described in detail with reference to FIGS. 5 and 6 are Mollier diagrams of the vapor part and CCLC part of the super CCLC, respectively. In FIG. 5, the vertical axis 550 represents pressure, the horizontal axis 552 represents entropy, and a number of isotherms 554 are shown along with a water saturation curve 556. Similarly, in FIG. 6, the vertical axis 650 represents pressure, the horizontal axis 652 represents entropy, and a number of isotherms 654 are shown along with the propane saturation curve 656. In FIG. 5, the water flow S of FIG. In FIG. 6, the primary coupled fluid flow A in FIG. 4 is drawn as a triple line A, the secondary coupled fluid flow B is drawn as a double broken line B, the first loop flow C is drawn as a solid line C, and the second loop flow D is drawn. The broken line D is drawn, and the third loop flow E is drawn as a broken line E. In order to make the drawing easy to see, a plurality of lines representing a fluid flow are separated from each other at a certain position so that they can be distinguished. Again for the sake of clarity, the temperature and pressure of each of the points (points) one or more conditions described above with respect to FIG. 4 in FIG. 5 and 6 (e.g., state A1, the state B 1, etc.) Represent symbolically. A single point may be used in these figures to make the figures easier to see, but those skilled in the art will recognize that the various states represented by each point are actually spaced apart. You can understand.

The super CCLC of FIG. 4 begins at point 501 (corresponding to states A 1 , B 1 , and C 1 ) for the purposes of this discussion, at which point water stream S is transferred to state S by water pump 402. Pressurized to 1 . The water stream S is heated to the point 502 (state S 2 ) under a substantially constant pressure by absorbing the heat Q 404 from the combustion exhaust gas H in the boiler 404. From here, the water stream S is expanded within the steam turbine 406 along a line of essentially constant entropy (not shown) to a point 503 (state S 3 ) to produce useful energy W 406 . The water stream S is then cooled to point 504 (state S 4 ) under a relatively constant pressure, during which time the water stream condenses from the gas phase to the liquid state. During this cooling step, the entropy of the water stream S is reduced by transferring entropy (heat) from the water stream S to the first loop stream of the CCLC portion of the system, as shown in FIG. Once cooled, water pump 402 pressurizes water stream S to point 501 (state S 1 ) at a relatively constant temperature and a new cycle begins. The steam cycle shown in FIG. 5 is similar to the steam cycle of a conventional steam power system, except that the medium that extracts the heat Q408 from the water stream S during cooling from point 503 to point 504 is mainly different.

The CCLC portion of the super-CCLC begins for this discussion at point 601 (corresponding to states A 2 , B 1 and C 1 ), at which point the primary coupled fluid flow A is initially a secondary coupled fluid. Divided into stream B and first loop stream C. All these fluid streams are in a liquid state. The first high pressure pump 414 pressurizes the first loop flow C to point 602 (state C 2 ) at a relatively constant temperature. The first loop stream C then evaporates by being heated at a substantially constant pressure to point 603 (state C3) by absorbing heat Q 408 from the first indirect heat exchanger 408. Once the first loop stream C evaporates, it expands along the constant entropy line (not shown) to a point 604 (state C 4 ) within the turbo expander 416 to generate useful energy W 4l6 . From point 604, the first loop stream C is mixed with other loop streams to form a primary coupled fluid stream A at point 605 (state A 1 ).

Meanwhile, the second high pressure pump 420 compresses the secondary combined fluid stream B to point 606 (corresponding to states B 2 , D 1 , and E 1 ) at a relatively constant temperature. At this point 606, the secondary coupled fluid stream B is split into a second loop stream D and a third loop stream E in states D1 and E1, respectively. From here, the second and third loop flows (D and E) are processed along separate paths. The second loop stream D is first heated to point 607 (state D2) by the flue gas H under almost constant pressure in the second indirect heat exchanger 428. The second loop stream D is then heated again by the flue gas H in the third indirect heat exchanger 430, again under substantially constant pressure, until it becomes steam at point 608 (state D 3 ). . The second loop stream D is then inflated along an essentially constant entropy line (not shown) until it reaches point 609 (state D 4 ) in the second turboexpander and is useful. Energy W 432 is generated. As can be seen from FIG. 6, at point 609, the second loop flow D still contains a relatively large amount of internal energy, as indicated by its relatively high entropy value. This energy is released into the third loop stream E in the fourth indirect heat exchanger 424, which cools the second loop stream D to point 610 (state D 5 ) under a relatively constant pressure. From here, the second loop flow D is mixed with other loop flows to form a primary coupled fluid flow A at point 605 (state A 1 ).

The third loop flow E starts at point 606 and is heated by the second loop flow D in the fourth indirect heat exchanger 424 under almost constant pressure until reaching point 611 (state E2). At point 611, the state of the third loop flow E is steam. From here, the third loop stream E is expanded along an essentially constant entropy line (not shown) in the third turbo expander 426 to produce useful energy W 426 . The third loop stream E exits the third turboexpander 426 at point 612 (state E 3 ) and is then mixed with the other loop streams to form the primary fluid stream A at point 605 (state A 1 ). .

After the three loop streams are combined to form the primary fluid stream A at point 605 (state A 1 ), the primary fluid stream A is relatively constant until it is completely liquefied at point 601 (state A2). And cooled in the condenser 410 under the pressure of At this point 601, the process begins anew.

By carefully selecting and controlling various states of the fluid flow, the present invention is intended to increase the efficiency of any prior art power system (including nuclear power systems, steam power systems and other power systems) or its deformation systems. Can be used. Table 3 provides approximate values for preferred embodiments of the various states identified in FIGS. 4-6 along with other data related to the operation of the embodiments. The working fluid in this embodiment is propane. These values, like the data given in Table 1, may vary substantially for specific operating conditions or requirements or other reasons, and such changes are within the scope of the invention.

The efficiency of the super-CCLC embodiment represented in Table 3 is that net power (W 406 + W 416 + W 426 + W 432 -P 402 -P 414 -P 420 ) entered the steam system from the heat source (Q 404 ). Calculated by dividing by the amount of heat. In preferred embodiments, the efficiency of super CCLC is at least about 25%, more desirably 30%. Moreover, as shown in Table 3, the efficiency of one preferred embodiment is about 33.5%, which is about 100 for that system if operated as a normal steam power generation system. % Increase. The addition of the CCLC portion to the steam system may in some cases reduce the power generated by the steam turbine 406, but this power loss is overcome by the additional power generated by the turbo expanders 416, 426 and 432. The Also, when changing or designing a steam system to the inventive super CCLC system, it is preferable to operate the steam portion of the system as a back pressure system (ie, the water stream has a positive pressure at the outlet of the steam turbine) and It is desirable to operate at a back pressure of at least 172.4 KPa (about 25 absolute psi). This back pressure ensures significant heat is transferred to the first loop cycle C of the CCLC portion of the system and provides significant power generation by the first turboexpander to help improve overall efficiency.

  The present invention is not limited to the embodiments presented above. Within the scope and spirit of the invention, the present invention can be modified to include additional heat exchangers, condensers, pumps, turboexpanders, mixers or flow separators. Alternatively, pumps, compressors, generators, etc. can be connected and driven using alternative configurations. A person skilled in the art may change or replace various devices described in this specification without departing from the scope and technical idea of the invention, and increase the number of devices. You will understand that it is good to reduce or reduce. The data provided for the preferred embodiments is also not intended to limit the invention and is shown in the values shown for these variables in the attached tables and in the accompanying drawings, as will be readily understood by those skilled in the art. Their relative relationships may be changed for a variety of reasons to accommodate various operating conditions, operating requirements, and the like. The preferred embodiments described in the specification are merely exemplary and are not intended to limit the scope of the invention in any way, which is limited by the scope of the appended claims. It is.

1 is a schematic diagram of an embodiment of a cascading closed loop cycle (CCLC) power generation system of the present invention. FIG. It is a Mollier diagram of the power generation cycle of CCLC of FIG. 1 is a schematic diagram of a typical prior art steam power generation system. FIG. 1 is a schematic diagram of an embodiment of the best cascading closed loop cycle (super CCLC) power generation system of the present invention. FIG. FIG. 5 is a Mollier diagram of the power generation cycle of the vapor portion of the super CCLC of FIG. 4. FIG. 5 is a Mollier diagram of a power generation cycle of a CCLC portion of the super CCLC of FIG. 4.

Claims (74)

  1. Supplying a working fluid;
    Increasing the pressure of the working fluid;
    Dividing the working fluid into a plurality of flows including at least a first flow and a second flow;
    Transferring a first amount of thermal energy from an energy source to the first stream and then transferring a second amount of thermal energy from the first stream to the second stream;
    Extracting a first amount of useful thermal energy from the first stream;
    Extracting a second amount of useful thermal energy from said stream 2;
    Combining the first stream and the second stream;
    Reducing the first and second flows to a minimum pressure that is approximately equal to or less than the vapor pressure at ambient temperature of the working fluid;
    An energy generation method comprising:
  2. 2. The energy generating method according to claim 1, wherein the working fluid is selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof.
  3.    2. The energy generating method of claim 1, wherein the minimum pressure is from about 172.37 absolute KPa to about 2068.43 absolute kPa (about 25 psia to about 300 psia).
  4.   The energy generation method of claim 1, wherein the ambient temperature is about -45.5 ° C to about 71.1 ° C (about -50 ° F to about 160 ° F).
  5.   2. The energy generation method of claim 1, wherein the energy source is selected from the group consisting of fossil fuel energy, nuclear energy, solar energy, geothermal energy, waste heat, hydrogen and combinations thereof.
  6. The method of generating energy of claim 1, wherein transferring a second amount of thermal energy from the first stream to the second stream comprises:
    Transferring a first portion of the second amount of thermal energy from the first stream to the second stream before the first stream and the second stream merge;
    Transferring the second portion of the second amount of thermal energy from the first stream to the second stream after the first stream and the second stream merge;
    An energy generation method comprising:
  7.   7. The energy generation method according to claim 6, wherein after extracting a first useful thermal energy amount from the first flow, the first portion of the second thermal energy amount is transferred from the first flow to the second flow. A method of generating energy that performs.
  8.   2. The energy generating method of claim 1 wherein the sum of the first useful thermal energy amount and the second useful thermal energy amount is equal to at least about 20% of the first thermal energy amount.
  9.   2. The method of generating energy of claim 1, wherein increasing the pressure of the working fluid increases the pressure of the working fluid from about 2068.43 absolute KPa to about 6894.76 absolute KPa (about 300 psia to about 1000 psia). An energy generation method including:
  10. A plurality of fluid conduits including at least a first fluid conduit, a second fluid conduit, and a combined fluid conduit that can contain a working fluid therein;
    A pump operably attached to the plurality of fluid conduits to pressurize the working fluid;
    Energy sources;
    A first heat exchanger operatively attached to the first fluid conduit and transferring a first amount of thermal energy from the energy source to the working fluid in the first fluid conduit;
    Operatively mounted downstream of the first heat exchanger with respect to the first fluid conduit and attached to the first fluid conduit and the second fluid conduit and from the working fluid in the first fluid conduit to the second A second heat exchanger for transferring a second amount of thermal energy to the working fluid in a fluid conduit;
    A first fluid expander operably attached to the first fluid conduit and extracting a first amount of useful thermal energy from the working fluid into the first fluid conduit;
    A second fluid expander operatively attached to the second fluid conduit and extracting a second amount of useful thermal energy from the working fluid in the second fluid conduit;
    Cooling operably attached to at least one of the plurality of fluid conduits to reduce the working fluid pressure to a minimum pressure that is approximately equal to or less than the vapor pressure at ambient temperature of the working fluid. With a vessel;
    An energy generating device comprising:
    The energy generating device, wherein the first fluid conduit and the second fluid conduit are coupled at a junction to form the coupled fluid conduit.
  11.   11. The energy generator of claim 10, wherein the working fluid is selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof.
  12.   11. The energy generator of claim 10, wherein the minimum pressure is from about 172.37 absolute KPa to about 2068.43 absolute kPa (about 25 psia to about 300 psia).
  13.   12. The energy generator of claim 10, wherein the ambient temperature is about −45.5 ° C. to about 71.1 ° C. (about −50 ° F. to about 160 ° F.).
  14.   11. The apparatus of claim 10, wherein the energy source is selected from the group consisting of fossil fuel burners, nuclear reactors, solar collectors, geothermal sources, waste heat sources, hydrogen, and combinations thereof.
  15. The energy generation device according to claim 10, wherein the second heat exchanger includes:
    A first portion of the second amount of thermal energy is disposed between the first fluid expander and the junction and is operatively attached to the first fluid conduit and the second fluid conduit with respect to the first fluid conduit. A primary second heat exchanger that transfers from the working fluid in the first fluid conduit to the working fluid in the second fluid conduit;
    Operatively disposed between the junction and the pump with respect to the coupling fluid conduit and operatively attached to the second fluid conduit and the coupling fluid conduit, and a second portion of the second amount of thermal energy within the coupling fluid conduit A secondary heat exchanger for transferring from the working fluid to the working fluid in the second fluid conduit;
    An energy generating device comprising.
  16.   16. The energy generating device of claim 15, wherein the second heat exchanger is disposed after the first fluid expander with respect to the first fluid conduit.
  17.   The energy generator of claim 10, wherein the sum of the first useful energy amount and the second useful energy amount is equal to at least about 20% of the first thermal energy amount.
  18.   11. The energy generator of claim 10, wherein the pump pressurizes the working fluid to about 2068.43 absolute KPa to about 6894.76 absolute KPa (about 300 psia to about 1000 psia).
  19. An energy conversion method that converts heat into useful energy:
    Providing a liquid coupled fluid stream;
    Pressurizing the combined fluid stream;
    Dividing the combined fluid stream into a primary fluid stream and a secondary fluid stream;
    Applying thermal energy to the primary fluid stream from a heat source to evaporate;
    Inflating the evaporated primary fluid stream to produce a first amount of useful energy;
    Transferring heat from the evaporated and expanded primary fluid stream to superheat the evaporated secondary fluid stream;
    Expanding the evaporated second fluid stream to produce a second amount of useful energy;
    Mixing the evaporated and expanded primary fluid stream with the evaporated and expanded secondary fluid stream to form a combined fluid stream;
    Transferring heat from the combined fluid stream to evaporate the secondary fluid stream;
    Condensing and liquefying the combined fluid stream;
    An energy conversion method comprising:
  20.   20. The energy conversion method of claim 19, wherein the fluid is selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof.
  21.   20. The energy conversion method of claim 19, wherein transferring heat from the combined fluid stream to evaporate the secondary fluid stream maintains the pressure of the combined fluid stream above the vapor pressure of the fluid. An energy conversion method further comprising:
  22. An energy conversion device that converts heat into useful energy:
    A combined fluid conduit carrying a fluid stream;
    A pump operably attached to the combined fluid conduit;
    A flow separator operatively attached to the combined fluid conduit downstream of the pump and operably attached to the primary fluid conduit and the secondary fluid conduit;
    A first heat exchanger operatively attached to the primary fluid conduit downstream of the flow separator and operably attached to a heat source;
    A first expander operatively attached to the primary fluid conduit downstream of the first heat exchanger;
    A second heat exchanger operatively attached to the primary fluid conduit downstream of the first expander and operably attached to the secondary fluid conduit;
    A third heat exchanger operatively attached to the secondary fluid conduit downstream of the fluid separator and operably attached to the combined fluid conduit;
    A second expander operatively attached to the secondary fluid conduit downstream of the second heat exchanger;
    A flow mixer operatively attached to the coupling fluid conduit, to the primary fluid conduit downstream of the second heat exchanger, and to a secondary fluid conduit downstream of the second expander;
    A cooler operably attached to the combined fluid conduit between the flow mixer and the pump;
    The third heat exchanger is disposed between the flow mixer and the cooler with respect to the combined fluid conduit, and the second heat exchanger is the third heat exchange with respect to the secondary fluid conduit. An energy conversion device disposed between the container and the second expander.
  23.   The energy conversion device of claim 22, wherein the fluid stream is selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof.
  24. 23. The energy conversion device of claim 22, wherein the energy source is selected from the group consisting of fossil fuel burners, nuclear reactors, solar collectors, geothermal sources, waste heat sources, hydrogen and combinations thereof.
  25. An efficiency improvement method for improving the efficiency of a power system having an energy source and a cooling system comprising:
    Transferring a first amount of thermal energy from the cooling system to a first loop of a cascading closed loop cycle system;
    Extracting a first useful energy amount from the first loop;
    Transferring a second amount of thermal energy from said energy source to a second loop of a cascading closed loop cycle system;
    Extracting a second useful energy amount from the second loop;
    An efficiency improvement method comprising:
  26.   26. The efficiency improvement method of claim 25, wherein the cascading closed loop cycle system includes a working fluid selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof.
  27. The method of improving efficiency of claim 25,
    Transferring a third amount of thermal energy from the second loop to a third loop of a cascading closed loop cycle system;
    Extracting a third amount of useful energy from the third loop;
    Further improving efficiency.
  28.   28. The efficiency improving method according to claim 27, wherein the power system receives a fourth amount of thermal energy from the energy source to generate a fourth useful energy amount, and the first useful energy amount, the second useful energy amount, The efficiency improving method, wherein a sum of the third useful energy amount and the fourth useful energy amount is equal to at least about 30% of the fourth thermal energy amount.
  29. An efficiency improvement method for improving the efficiency of a power system having an energy source and a cooling system comprising:
    Supplying a working fluid;
    Increasing the pressure of the working fluid;
    Dividing the working fluid into a plurality of flows including at least a first flow and a second flow;
    Transferring a first amount of thermal energy from the cooling system to the first stream;
    Extracting a first amount of useful energy from the first stream;
    Transferring a second amount of thermal energy from the energy source to a second stream;
    Extracting a second amount of useful energy from the second stream;
    Cooling the working fluid to a minimum pressure that is approximately equal to or less than the vapor pressure at ambient temperature of the working fluid;
    An efficiency improvement method comprising:
  30. 30. The method of improving efficiency of claim 29, wherein the second stream comprises a primary second stream and a secondary second stream,
    Transferring a second amount of thermal energy from the energy source to the second stream,
    Transferring the second amount of thermal energy from the energy source to a primary second stream;
    Transferring a portion of the second amount of thermal energy from the primary second stream to the secondary second stream;
    Including efficiency improvement methods.
  31. The efficiency improvement method of claim 30, wherein extracting a second useful energy amount from the second flow comprises:
    Extracting a portion of the second useful energy amount from the primary second stream;
    Extracting a portion of the second useful energy amount from the secondary second stream;
    Including efficiency improvement methods.
  32.   30. The efficiency improving method of claim 29, wherein the working fluid is selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof.
  33.   30. The efficiency improving method of claim 29, wherein the minimum pressure is from about 172.37 absolute KPa to about 2068.43 absolute kPa (about 25 psia to about 300 psia).
  34.   30. The method of claim 29, wherein the ambient temperature is about -45.5 [deg.] C to about 71.1 [deg.] C (about -50 [deg.] F to about 160 [deg.] F).
  35.   30. The efficiency improvement method of claim 29, wherein the energy source is selected from the group consisting of fossil fuel energy, nuclear energy, solar energy, geothermal energy, waste heat, hydrogen, and combinations thereof.
  36.   30. The efficiency improvement method of claim 29, wherein the power system is a steam power generation system.
  37.   30. The method of improving efficiency of claim 29, wherein increasing the pressure of the working fluid comprises pressurizing the working fluid to about 2068.43 absolute KPa to about 6894.76 absolute KPa (about 300 psia to about 1000 psia). Including efficiency improvement methods.
  38. An energy generation method for generating energy comprising:
    Supplying a first working fluid;
    Increasing the pressure of the first working fluid;
    Transferring a first amount of thermal energy from an energy source to the first working fluid;
    Extracting a first useful energy amount from the first working fluid;
    Supplying a second working fluid;
    Increasing the pressure of the second working fluid;
    Dividing the second working fluid into a plurality of fluid streams including at least a first stream and a second stream;
    Transferring a second amount of thermal energy from the first working fluid to the first stream;
    Extracting a second amount of useful energy from the first stream;
    Transferring a third amount of thermal energy from the energy source to the second stream;
    Extracting a third amount of useful energy from the second stream;
    Cooling the second working fluid to a minimum pressure that is approximately equal to or less than a vapor pressure at an ambient temperature of the second working fluid;
    An energy generation method comprising:
  39. 39. The energy generation method of claim 38, wherein the second flow includes a primary second flow and a secondary second flow,
    Transferring a third amount of thermal energy from the energy source to the second stream,
    Transferring the third amount of thermal energy from the energy source to the primary second stream;
    Transferring a portion of the third amount of thermal energy from the primary second stream to the secondary second stream;
    An energy generation method including:
  40. 40. The energy generating method of claim 39, wherein extracting a third useful energy amount from the second flow comprises:
    Extracting a first portion of the third useful energy amount from the primary second stream;
    Extracting a second portion of the third useful energy amount from the secondary second stream;
    An energy generation method including:
  41.   39. The energy generating method according to claim 38, wherein the first working fluid is water.
  42.   40. The energy generating method of claim 38, wherein the second working fluid is selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof.
  43.   40. The method of generating energy of claim 38, wherein the minimum pressure is from about 172.37 absolute KPa to about 2068.43 absolute kPa (about 25 psia to about 300 psia).
  44.   40. The method of claim 38, wherein the ambient temperature is about -45.5 [deg.] C to about 71.1 [deg.] C (about -50 [deg.] F to about 160 [deg.] F).
  45.   40. The energy generation method of claim 38, wherein the energy source is selected from the group consisting of fossil fuel energy, nuclear energy, solar energy, geothermal energy, waste heat, and combinations thereof.
  46. An efficiency improvement method for improving the efficiency of a power system having an energy source and a cooling system comprising:
    Supplying a working fluid;
    Increasing the pressure of the working fluid;
    Dividing the working fluid into a first flow, a second flow and a third flow;
    Transferring a first amount of thermal energy from the cooling system to the first stream;
    Extracting a first amount of useful energy from the first stream;
    Transferring a second amount of thermal energy from the energy source to the second stream;
    Extracting a second amount of useful energy from the second stream;
    Transferring a third amount of thermal energy from the second stream to the third stream;
    Extracting a third amount of useful energy from the third stream;
    Cooling the working fluid to a minimum pressure that is approximately equal to or less than the vapor pressure at ambient temperature of the working fluid;
    An efficiency improvement method comprising:
  47. The efficiency improving method of claim 46, comprising:
    Transferring a second amount of thermal energy from the energy source to the second stream,
    Transferring a first portion of the second amount of thermal energy from the energy source to the second stream in a first heat exchanger;
    Transferring a second portion of the second amount of thermal energy from the energy source to the second stream in a second heat exchanger;
    Including efficiency improvement methods.
  48. The efficiency improving method of claim 46, comprising:
    Extracting a first amount of useful energy from the first stream includes expanding the first stream in a first expander;
    Extracting the second amount of useful energy from the second stream includes expanding the second stream in a second expander;
    Extracting a third amount of useful energy from the third stream expands the third stream in a third expander;
    Including efficiency improvement methods.
  49.   47. The efficiency improving method according to claim 46, wherein the working fluid is selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof.
  50.   47. The efficiency improving method of claim 46, wherein the minimum pressure is from about 172.37 absolute KPa to about 2068.43 absolute kPa (about 25 psia to about 300 psia).
  51.   47. The efficiency improving method according to claim 46, wherein the ambient temperature is about −45.5 ° C. to about 71.1 ° C. (about −50 ° F. to about 160 ° F.).
  52.   47. The efficiency improving method of claim 46, wherein the energy source is selected from the group consisting of fossil fuel energy, nuclear energy, solar energy, geothermal energy, waste heat, hydrogen and combinations thereof.
  53.   47. The efficiency improving method according to claim 46, wherein the power system is a steam power generation system.
  54. A supplemental energy generating device for generating supplemental energy from a power system having an energy source and a cooling system comprising:
    A plurality of fluid conduits including at least a first fluid conduit, a second fluid conduit, and a combined fluid conduit that can contain a working fluid therein;
    One or more pumps operatively attached to the plurality of fluid conduits and pressurizing the working fluid;
    A first heat exchanger operatively attached to the first fluid conduit and transferring a first amount of thermal energy from the cooling system to the working fluid in the first fluid conduit;
    A first fluid expander operably attached to the first fluid conduit and extracting a first amount of useful energy from the working fluid in the first fluid conduit;
    A second heat exchanger operatively attached to the second fluid conduit and transferring a second amount of thermal energy from the energy source to the working fluid in the second fluid conduit;
    A second fluid expander operatively attached to the second fluid conduit and extracting a second amount of useful energy from the working fluid in the second fluid conduit;
    A cooler movably attached to at least one of the plurality of fluid conduits, wherein the pressure of the fluid is reduced to a minimum pressure that is approximately equal to or less than the vapor pressure at an ambient temperature of the working fluid; A cooler to reduce;
    And wherein the first fluid conduit and the second fluid conduit are joined at one or more junctions to form a combined fluid conduit.
  55. 55. The supplemental energy generating device of claim 54, wherein the plurality of fluid conduits further includes a third fluid conduit,
    Third heat operatively attached to the second fluid conduit and the third fluid conduit to transfer a third amount of thermal energy from the working fluid in the second fluid conduit to the working fluid in the third fluid conduit. With an exchange;
    A third fluid expander operably attached to the third fluid conduit and extracting a third amount of useful energy from the working fluid in the third fluid conduit;
    And wherein the third heat exchanger is disposed after the second fluid expander with respect to the second fluid conduit.
  56.   55. The supplemental energy generating device of claim 54, wherein the second heat exchanger includes two or more heat exchangers.
  57.   55. The supplemental energy generator of claim 54, wherein the working fluid is selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof.
  58.   55. The supplemental energy generator of claim 54, wherein the minimum pressure is from about 172.37 absolute KPa to about 2068.43 absolute KPa (about 25 psia to about 300 psia).
  59.   55. The supplemental energy generator of claim 54, wherein the ambient temperature is about −45.5 ° C. to 71.1 ° C. (about 50 ° F. to about 160 ° F.).
  60.   55. The supplemental energy generator of claim 54, wherein the energy source is selected from the group consisting of fossil fuel burners, nuclear reactors, solar collectors, geothermal sources, waste heat sources, hydrogen and combinations thereof. .
  61.   55. The supplemental energy generator of claim 54, wherein the power system receives a fourth thermal energy from the energy source to generate a fourth useful energy amount, the first useful energy amount and the second useful energy amount. And a sum of the third useful energy amount and the fourth useful energy amount equal to at least about 30% of the fourth thermal energy amount.
  62. An energy conversion device that converts thermal energy to useful energy:
    Comprising a primary power system and a secondary power system;
    The primary power system is:
    Energy sources;
    A primary fluid conduit that may contain a primary working fluid therein;
    A primary liquid pump operatively attached to the primary fluid conduit and pressurizing the working fluid;
    A primary fluid heat exchanger operatively attached to the primary fluid conduit and transferring a first amount of thermal energy from an energy source to the primary fluid in the primary fluid conduit;
    A primary fluid expander operably attached to the primary fluid conduit and extracting a first amount of useful energy from the primary working fluid in the primary fluid conduit;
    And comprising
    The secondary power system is
    A secondary fluid conduit system including a first fluid loop, a second fluid loop, and a third fluid loop that may contain a secondary working fluid therein;
    One or more secondary fluid pumps operatively attached to the secondary fluid conduit system and pressurizing the secondary working fluid;
    A first heat exchanger disposed between the primary fluid expander and the primary fluid pump with respect to the primary fluid conduit and operatively attached to the first fluid loop and the primary fluid conduit, the primary operation A first heat exchanger for transferring a second amount of thermal energy from the primary fluid in a fluid conduit to the secondary working fluid in the first fluid loop;
    A first fluid expander operatively attached to the first fluid loop for extracting a second amount of useful energy from the secondary working fluid in the first fluid loop;
    A second heat exchanger operatively attached to the second fluid loop and transferring a third amount of thermal energy from the energy source in the second fluid loop to the secondary working fluid;
    A second fluid expander operably attached to the second fluid loop and extracting a third amount of useful energy from the secondary working fluid in the second fluid loop;
    A third heat exchanger disposed after the second fluid expander with respect to the second fluid loop and operably attached to the second fluid loop and the third fluid loop, the second fluid loop being in the second fluid loop; A third heat exchanger for transferring a fourth amount of thermal energy from the secondary working fluid of the second fluid to the secondary working fluid in the third fluid loop;
    A third fluid expander operatively attached to the third fluid loop for extracting a fourth amount of useful energy from the secondary working fluid in the second fluid loop;
    A cooler operably attached to the secondary fluid conduit, wherein the pressure of the secondary working fluid is reduced to a minimum pressure that is approximately equal to or less than the vapor pressure at ambient temperature of the secondary working fluid. A cooler to reduce;
    An energy conversion device comprising:
  63.   64. The energy conversion device of claim 62, wherein the primary working fluid is water.
  64.   64. The energy conversion device of claim 62, wherein the secondary working fluid is selected from the group consisting of propane, propylene, light hydrocarbons, and combinations thereof.
  65.   64. The energy conversion device of claim 62, wherein the minimum pressure is about 172.37 absolute KPa to about 2068.43 absolute KPa (about 25 psia to about 300 psia).
  66.   64. The energy conversion device of claim 62, wherein the ambient temperature is about −45.5 ° C. to 71.1 ° C. (about 50 ° F. to about 160 ° F.).
  67.   63. The energy conversion device of claim 62, wherein the energy source is selected from the group consisting of fossil fuel burners, nuclear reactors, solar collectors, geothermal sources, waste heat sources, hydrogen and combinations thereof.
  68.   63. The energy conversion device according to claim 62, wherein a sum of the first useful energy amount, the second useful energy amount, the third useful energy amount, and the fourth useful energy amount is the first thermal energy amount. An energy conversion device equal to at least about 30%.
  69.   64. The energy conversion device of claim 62, wherein the one or more secondary fluid pumps pressurize the secondary working fluid to about 2068.43 absolute KPa to about 6894.76 absolute KPa (about 300 psia to about 1000 psia). .
  70. A method of converting heat into useful energy based on a cascading closed loop cycle (CCLC), which includes the following steps:
    A) supplying a propane primary liquid stream to a primary indirect heat exchanger and evaporating said propane primary liquid stream using thermal energy obtained from a heat source;
    B) Expanding the evaporated propane primary stream in a primary expansion turbine to create useful energy;
    C) directing the evaporated propane primary stream exiting the primary expansion turbine to a secondary indirect heat exchanger;
    D) superheat the evaporated propane secondary stream in a secondary indirect heat exchanger;
    E) expanding the superheated propane secondary stream in a secondary expansion turbine to create useful energy;
    F) directing the evaporated propane primary stream exiting the secondary indirect heat exchanger to a flow mixer;
    G) directing the evaporated propane secondary stream exiting the secondary expansion turbine to the flow mixer;
    H) combining the evaporated propane primary and secondary streams in the flow mixer;
    I) directing the evaporated propane combined stream to a tertiary indirect heat exchanger to evaporate the liquid propane secondary stream;
    J) directing the evaporated propane combined stream to a condenser to cool and liquefy;
    K) directing the combined stream of liquid propane exiting the condenser to a pump;
    L) pressurizing the liquid propane combined stream in the pump;
    M) separating the pressurized combined stream of liquid propane discharged from the pump into a primary propane stream and a secondary propane stream in the flow separator;
    N) directing the liquid propane primary stream to step A to evaporate the pressurized liquid propane primary stream;
    O) Lead the liquid propane secondary stream to step I to evaporate the pressurized liquid propane secondary stream.
  71.   71. The energy conversion method of claim 70, wherein the ORC medium is propylene.
  72.   71. The energy conversion method of claim 70, wherein the ORC medium is a light hydrocarbon.
  73.   71. The energy conversion method of claim 70, wherein the ORC medium is a mixture of light hydrocarbons.
  74.   The energy conversion method according to claim 70, wherein the discharge pressure of the expansion turbine is controlled to maintain the discharge pressure of the third indirect heat exchanger so as to exceed the vapor pressure of the ORC medium.
JP2005505522A 2002-07-22 2003-07-18 Cascading closed-loop cycle power generation Granted JP2005533972A (en)

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US10/199,257 US6857268B2 (en) 2002-07-22 2002-07-22 Cascading closed loop cycle (CCLC)
US10/377,114 US7096665B2 (en) 2002-07-22 2003-03-03 Cascading closed loop cycle power generation
PCT/US2003/022399 WO2004009965A1 (en) 2002-07-22 2003-07-18 Cascading closed loop cycle power generation

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JP2005533972A true JP2005533972A (en) 2005-11-10

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011069370A (en) * 2009-09-28 2011-04-07 General Electric Co <Ge> Double reheating rankine cycle system and method for the same
WO2011119650A3 (en) * 2010-03-23 2012-01-12 Echogen Power Systems, Llc Heat engines with cascade cycles
JP2012527395A (en) * 2009-05-22 2012-11-08 サソール テクノロジー(プロプライエタリー)リミテッド Process for co-production of syngas and electricity
WO2013059687A1 (en) * 2011-10-21 2013-04-25 Echogen Power Systems, Llc Heat engine and heat to electricity systems and methods with working fluid mass management control
US9284855B2 (en) 2010-11-29 2016-03-15 Echogen Power Systems, Llc Parallel cycle heat engines
US9638065B2 (en) 2013-01-28 2017-05-02 Echogen Power Systems, Llc Methods for reducing wear on components of a heat engine system at startup
US9752460B2 (en) 2013-01-28 2017-09-05 Echogen Power Systems, Llc Process for controlling a power turbine throttle valve during a supercritical carbon dioxide rankine cycle
US9863282B2 (en) 2009-09-17 2018-01-09 Echogen Power System, LLC Automated mass management control

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7100380B2 (en) * 2004-02-03 2006-09-05 United Technologies Corporation Organic rankine cycle fluid
US8046999B2 (en) 2007-10-12 2011-11-01 Doty Scientific, Inc. High-temperature dual-source organic Rankine cycle with gas separations
US20140000261A1 (en) * 2012-06-29 2014-01-02 General Electric Company Triple expansion waste heat recovery system and method
EP3353387A1 (en) * 2014-09-19 2018-08-01 Ect Power AB A multistage evaporation organic rankine cycle
KR101947877B1 (en) 2016-11-24 2019-02-13 두산중공업 주식회사 Supercritical CO2 generation system for parallel recuperative type

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4003205A (en) * 1974-08-09 1977-01-18 Hitachi, Ltd. Method and apparatus for operating a steam turbine plant having feed water heaters
JPH03271507A (en) * 1990-03-22 1991-12-03 Toshiba Corp Compound generation plant
US6422017B1 (en) * 1998-09-03 2002-07-23 Ashraf Maurice Bassily Reheat regenerative rankine cycle

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5664414A (en) * 1995-08-31 1997-09-09 Ormat Industries Ltd. Method of and apparatus for generating power
US5953918A (en) * 1998-02-05 1999-09-21 Exergy, Inc. Method and apparatus of converting heat to useful energy
US6195997B1 (en) * 1999-04-15 2001-03-06 Lewis Monroe Power Inc. Energy conversion system
FR2879234B1 (en) * 2004-12-13 2010-06-18 Gerard Murat Refrigerating fluid thermodynamic machine with continuous circulation

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4003205A (en) * 1974-08-09 1977-01-18 Hitachi, Ltd. Method and apparatus for operating a steam turbine plant having feed water heaters
JPH03271507A (en) * 1990-03-22 1991-12-03 Toshiba Corp Compound generation plant
US6422017B1 (en) * 1998-09-03 2002-07-23 Ashraf Maurice Bassily Reheat regenerative rankine cycle

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2012527395A (en) * 2009-05-22 2012-11-08 サソール テクノロジー(プロプライエタリー)リミテッド Process for co-production of syngas and electricity
US9021814B2 (en) 2009-05-22 2015-05-05 Sasol Technology (Proprietary) Limited Process for co-producing synthesis gas and power
US9863282B2 (en) 2009-09-17 2018-01-09 Echogen Power System, LLC Automated mass management control
JP2011069370A (en) * 2009-09-28 2011-04-07 General Electric Co <Ge> Double reheating rankine cycle system and method for the same
WO2011119650A3 (en) * 2010-03-23 2012-01-12 Echogen Power Systems, Llc Heat engines with cascade cycles
US9284855B2 (en) 2010-11-29 2016-03-15 Echogen Power Systems, Llc Parallel cycle heat engines
WO2013059687A1 (en) * 2011-10-21 2013-04-25 Echogen Power Systems, Llc Heat engine and heat to electricity systems and methods with working fluid mass management control
US9638065B2 (en) 2013-01-28 2017-05-02 Echogen Power Systems, Llc Methods for reducing wear on components of a heat engine system at startup
US9752460B2 (en) 2013-01-28 2017-09-05 Echogen Power Systems, Llc Process for controlling a power turbine throttle valve during a supercritical carbon dioxide rankine cycle

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WO2004009965A1 (en) 2004-01-29
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EP1546512A4 (en) 2007-11-14
AU2003252000B2 (en) 2009-04-23
IL166382D0 (en) 2006-01-16
KR20050056941A (en) 2005-06-16
AU2003252000C1 (en) 2009-10-29
CA2493155A1 (en) 2004-01-29
AU2003252000A1 (en) 2004-02-09

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