WO1999023422A1

WO1999023422A1 - Heating system utilizing a turbo-machine for self-sustained operation

Info

Publication number: WO1999023422A1
Application number: PCT/US1998/023319
Authority: WO
Inventors: Edward M. Halimi; William E. Woollenweber
Original assignee: Turbodyne Systems, Inc.
Priority date: 1997-11-03
Filing date: 1998-11-02
Publication date: 1999-05-14
Also published as: AU1299299A

Abstract

Methods and systems for a self-sustaining heating system (10) using the energy of the hot exhaust gas of a fuel after its combustion in a burner assembly (12). The energy in the products of combustion power a turbo-machine (20) mounted on a shaft having a centrifugal air compressor (28) that delivers a flow of air to the burner for sustaining combustion of the fuel. An electric motor-generator (32) is coupled to the shaft of the turbo-machine for the purpose of starting the turbo-machine (20) and bringing it up to speed for operation in a self-sustained mode. When the system has reached self-sustaining operation, excess energy in the exhaust gas can be converted to electric energy by changing the motor-generator (32) to act as a generator through the use of appropriate electronic controls. This electric power can be used for powering other electrical devices in the heating system, and for recharging the battery used for starting the heating system. The system (10) can be self-sustaining and requires no connections to an outside power source for normal operation.

Description

HEATING SYSTEM UTILIZING A TURBO-MACHINE FOR SELF-SUSTAINED OPERATION

Field of the Invention

This invention relates to heating systems and, more particularly, to fuel burning heating systems for heating fluids, such as air or water, and circulating the heated fluid through a system of heat exchangers.

Background of the Invention

Commercially available heating systems commonly comprise an outer shell or casing wherein a burner assembly is located for maintaining combustion. Generally, a liquid or gaseous fuel is supplied to the burner assembly where it is ignited and burned. In these commercially available systems heat generated by the combustion process is transferred to a liquid media or air through a heat exchanger, and the heated media is then circulated through piping or ductwork to an area where the ambient temperature needs to be raised.

In hot water heating systems, radiators are located in rooms or enclosures where the hot water transfers heat to the surrounding atmosphere until the desired air temperature is reached. Hot air systems usually utilize a motor-driven fan to circulate heated air through the areas to be heated. Both hot water and hot air systems require electric motors to run circulation pumps in the case of hot water systems and to run a fan or blower in the case of hot air systems. There are other electrical needs in complete systems, such as supplying current to a fuel pump, powering the ignition means for lighting the burner, and supplying power to operate various valves and monitoring devices.

Using two types of energy sources to heat a desired area significantly raises the costs associated with these types of heating systems and wastes valuable resources. Summary of the Invention

The present invention sets forth a heating system that can operate, once started, without the use of an outside source of electric energy, such as that supplied from a commercial energy grid. The invention utilizes the energy in the by-products of combustion to power a turbo-machine that is mounted on a shaft having a centrifugal air compressor that delivers a flow of air to the burner for sustaining combustion of the fuel. The turbo-machine described herein is similar in principle to a turbocharger commonly used to supercharge internal combustion engines.

An electric motor-generator is coupled to the shaft of the turbo-machine for the purpose of starting the turbo-machine and bringing it up in speed for operation in a self-sustained mode. Power to operate the electric motor used for starting the turbo-machine can be supplied from separate source of electric energy, such as a conventional battery or set of batteries. In addition, the heating system may be provided with means for generating auxiliary power, such as thermo-electric modules or photo-electric cells, connected with the heating system to generate additional power for the electrical components of the heating system.

When the turbo-machine and motor-generator have reached a self-sustaining speed, excess energy in the exhaust gas can be converted to electric energy by changing the motor-generator to act as a generator through the use of an appropriate electronic control. The electric power generated can be used for powering other electrical devices in the heating system, and for recharging a battery used for starting the heating system. In this manner, the system can be self-sustaining and require no connections to an outside power source for normal operation. An emergency connection can be provided so that, if the battery-generator system were to become inoperative, the system can be operated from commercially available electric power.

Brief Description of the Drawings FIG. 1 is a diagrammatic illustration of a self-sustained heating system having liquid as a heat conveying medium.

FIG. 2 is a diagrammatic illustration of a self-sustained heating system which uses air as a heat conveying medium. FIG. 3 schematically illustrates a self-sustaining heating system with means for providing auxiliary power to the heating system.

Detailed Description of the Invention

As shown in FIG. 1, one heating system 10 of the invention using a liquid, such as water for a heat conveying medium includes a first means 12 for burning a fuel and generating heat, a second means 14 for conveying the hot exhaust from the first means 12, a third means 16 for transferring heat from the hot exhaust conveyed thereto by the second means 14 to a liquid heat conveying medium, a fourth means 18, such as a liquid pump, for circulating the heat conveying medium in a loop including the third means 16 and a further heat transfer means 17, such as a radiator, for transfer of heat from the heat conveying liquid to atmosphere, and a fifth means 20 such as a turbo-machine connected with the second means 14 and receiving and extracting energy from the hot exhaust gas for use in operation of the heating system.

In the heating system 10 the first means 12 for burning fuel and generating heat comprises a burner 12, a fuel supply 24 and a fuel pump 22. The second means 14 is connected with the fifth means 20, which comprises turbo-machine 20, more specifically, the second means 14 is connected with a turbine 26 of the turbo-machine and delivers the hot exhaust gas to the turbine inlet. The second means 14 also connects the outlet of the turbine 26 with the third means 16, which is a heat exchanger for transferring a portion of the heat from the burner exhaust gas to a heat conveying liquid. The heat exchanger 16 may be connected by the second means 14 with the burner 12 in series, as shown in FIG. 1, or in parallel with said turbo- machine 20 (not shown). The heat conveying liquid is circulated in the heating system 10 through the heat exchanger 16 and the further heat transfer means 17 by the fourth means 18, which comprises a circulating pump 18 and a electric motor 38. The fifth means, e.g., turbo-machine 20, which is connected with the burner 12 by the second conduit means 14, comprises a turbine 26 and a compressor 28 connected by a shaft 30.

In continuous operation of the system 10, the turbine 26 of said turbo-machine 20 receives the exhausting by-products of the burning fuel from the burner 12 through second conduit means 14. The energy of the exhausting by-products of the burning fuel causes the turbine 26 to rotate. The turbine 26 is connected to a rotating shaft 30 at one end, and the other end of the rotating shaft 30 drives the compressor 28. The compressor inlet is in communication with the atmosphere, and as the turbine 26 rotates, the compressor 28 also rotates thereby causing air to be drawn from the atmosphere into the air inlet of the compressor 28. The air is compressed by the compressor 28 and is then directed from output of the compressor 28 to the burner 12 for use in combustion of the fuel.

As depicted in FIG. 1, a motor-generator 32 is also connected with the rotating shaft 30 of the turbo-machine 20. The motor-generator 32 is controlled by a controller 34 which receives inputs from a temperature control means 36 for monitoring and controlling temperature, such as a thermostat. During initial start up of the heating system 10 in response to a signal from the temperature control means 36, the motor-generator 32 is operated by the controller 34 as a motor. The controller 34 energizes the motor-generator 32 from a source of electrical energy 39, such as a battery, which drives the rotating shaft 30 of turbo-machine 20 so it provides combustion air to support burning of the fuel in the burner 12.

The motor-generator 32 continues to supply rotational energy to the turbo- machine 20 until a turbo-machine speed signal indicates to the controller 34 that the heating system 10 can operate in a self-sustained mode. The heating system 10 is then able to run self-sustained from the energy available in the hot exhaust gas delivered from the burner 12 to the input of the turbine 26 of said turbo-machine 20. When the energy delivered from the exhaust gas to the turbo-machine 20 is high enough, as determined from the turbo-machine speed, the controller 34 will control operation of the motor-generator 32 to operate as a generator and will deliver electrical energy from the motor-generator 32 through the controller 34 to other components of the heating system 10 and to recharge the electrical energy source 39.

The controller 34 can deliver power from the motor-generator 32 to operate, for example, a motor 38 for the pump 18 that circulates the heat conveying liquid, an ignition means 40 for igniting fuel in the burner 12, a fuel pump 22 where a liquid fuel such as oil is delivered from an oil source 24, or a gas control valve in place of the fuel pump 22 where a gaseous fuel, such as natural gas or propane, is used as fuel. The heat conveying medium is preferably a fluid, such as water or air, that is capable of absorbing heat in a heat exchanger and conveyance to transfer its absorbed heat to an area or space to be heated. Conventional heating systems frequently use air and water to transfer heat from the combustion by-products (e.g., hot exhaust gas) of a burning fuel to living and working spaces.

In addition, energization of all of the electrical systems contained in the heating system 10 can be supplemented from the electrical source 39 by controller 34 for a short period of time if necessary. The power supply 39 used to start the heating system 10 can consist of at least one battery, with an optional emergency means for connecting the heating system 10 to a commercial power grid in the case of emergency or low battery charge. Finally, the motor-generator 32 may also be used to recharge the batteries when excess power is available.

Thus, the invention described herein can be applied to heating systems using various kinds of fuel and, in the case of natural gas supplied from a commercial system under pressure, the fuel pump and tank shown in FIG. 1 would not be necessary. The efficiency of the gas-fired self-sustaining heating system would be higher than an oil-fired system since power from the heating system is not needed to supply gas as it is needed to drive the oil pump of an oil-fired system. As indicated above, the heat exchanger 16 transfers a portion of the heat of the exhaust gas from the burner 12 to a heat conveying liquid for subsequent transfer to atmosphere. In preferred embodiments of the invention, after passing through heat exchanger 16 the exhausting by-products of the burning fuel may be directed through a second heat exchanger 42 which is connected with the output of said compressor 28, thereby preheating the combustion air from compressor 28 prior to its entry into the burner 12. In addition, a third heat exchanger 44 may also be connected with the exhausting by-products of the burning fuel for preheating the liquid fuel prior to its entry into burner 12. Thus, the system 10 provides an effective use of the heat of the exhausting by-products of the burning fuel before the exhaust exits the system to the atmosphere, and the invention contributes to the overall efficiency of the heating system 10. The heating system shown in FIG. 1 is a liquid based heating system 10 that can use, for example, water as the heat conveying medium to transfer heat from the exhausting by-products of the burning fuel to a space to be heated. In such systems, after being heated in heat exchanger 16, the heat conveying liquid is directed to at least one radiator means 46 for dissipating the heat within said heat conveying fluid to the area or space to be heated.

The invention can also be embodied in a system using air as the heat conveying medium. FIG. 2 illustrates such an air based heating system 50 utilizing a turbo-machine for self-sustaining operation. In this embodiment of the invention where air is used as the heat conveying fluid instead of water, the second means 16 is an air heat exchanger, and the hot exhaust gas from burner 12 passes through heat exchanger 16 and heats air that is subsequently circulated through an area or space to be heated. The heated air is circulated through the heating system 50 to the space 37 to be heated by a blower 52 which is driven by the electric motor 41. An air filter 54 may also be inserted in the heating air's circulation path to remove particulates from the air before entering the heat exchanger 16. Since air is used as the heat conveying medium instead of water, radiator means are no longer necessary because the hot air can be directly circulated to the area 37 to be heated. The system 50 can be started in the same fashion as system 10 by a control 34 in response to a signal from a thermostat 36 in the space to be heated. The control 34 can energize a motor-generator 32 to drive the turbo-machine 20 on start up, and the turbo- machine's compressor 28 can deliver combustion air to the burner 12. In addition, the motor-generator 32 can drive a fuel pump 22 to deliver fuel for combustion to the burner 12. When the burner 12 is providing exhaust gas with sufficient energy to drive the turbo-machine turbine 26, the control 34 can switch the motor-generator 32 to operate as a generator and can deliver the motor-generator output electrical energy to recharge battery 39 and/ or to drive the blower motor 41.

The system 80 of FIG. 3 includes, in addition to a battery 39, means for providing auxiliary power 60 to help keep the batteries charged and provide extra energy to the heating system. The means for providing additional auxiliary power 60 can be connected with the controller 34, but may also be connected with any individual electrical component of the system. The means for providing auxiliary power 60 can be an electrical generation source, such as, for example, a thermoelectric module that receives heat from the burner exhaust gas or photo-electric cells. In preferred systems thermo-electric modules may be attached in heat transfer relationship to a component of the system that becomes heated from the burner exhaust gas.

While the invention has been described in its currently best known mode and embodiments, other modes and embodiments of the invention will be apparent to those skilled in the art and the invention is limited only by the scope of the claims that follow.

Claims

We Claim;

1. A heating system, comprising: first means for burning a fuel and generating heat therefrom; second means connected with said first means for exhausting by- products of the burning of said first means; third means for transferring a portion of the heat from the exhausting by-products of said first means to a heat conveying fluid; fourth means for circulating said heat conveying fluid for subsequent transfer of heat from said heat conveying fluid to a space to be heated; and fifth means, comprising a turbine in communication with said second means for extracting energy from the exhausting by-products of said first means and for operating said first means and said fourth means.

2. The heating system of claim 1 wherein the heat conveying fluid is water.

3. The heating system of claim 1 wherein the heat conveying fluid is air.

4. The heating system of claim 1 wherein the turbine is part of a turbo- machine including a compressor, and the compressor supplies combustion air to the first means.

5. The heating system of claim 1 wherein said turbine is connected to and drives a motor-generator and said motor-generator operates the fourth means.

6. The heating system of claim 1 further comprising sixth means for providing power to at least one of said system means.

7. The heating system of claim 6 wherein said sixth means comprises a motor-generator connected to said fifth means and a battery to drive said motor- generator and fifth means.

8. The heating system of claim 6 wherein said sixth means comprises a battery and auxiliary power means.

9. The heating system of claim 8 wherein said auxiliary power means comprises a thermo-electric module.

10. The heating system of claim 8 wherein said auxiliary power means comprises a photo-electric cell.

11. In a heating system including a fuel pump, a fuel burner, a burner exhaust, a heat exchanger for heating a fluid, and means for circulating the heating fluid, the improvement comprising turbine means driven from the burner exhaust for operating at least one of the fuel pump, fuel burner, and means for circulating the heating fluid.

12. The improvement of claim 11 wherein the heating fluid is liquid and the means for circulating the heating fluid is a liquid pump.

13. The improvement of claim 11 wherein the heating fluid is air and the means for circulating the heating fluid is an air blower.

14. The improvement of claim 11 wherein the turbine means drives a compressor for supplying combustion air to the fuel burner.

15. The improvement of claim 11 wherein the heating system includes an electric battery, and the turbine means is connected with a motor-generator that is connected with the electric battery and is driven by the motor-generator to start operation of the heating system.

16. The improvement of claim 15 wherein the turbine means drives the motor-generator and the motor-generator recharges the electric battery while the heating system is in operation.

17. The improvement of claim 11 further comprising means for providing power to start said heating system.

18. The improvement of claim 17 wherein said means for providing power comprises an electric battery.

19. The improvement of claim 18 wherein said means for providing power further comprises an auxiliary power means.

20. The improvement of claim 19 wherein said auxiliary power means comprises one or more thermo-electric modules.

21. The improvement of claim 19 wherein said auxiliary power means comprises one or more photo-electric cells.

22. A method of operating a heating system comprising delivering a flow of combustible fuel and air to a fuel burner; burning a mixture of fuel and air and generating a flow of hot gas; extracting a portion of the energy from the flow of hot gas in a rotating turbine wheel as kinetic energy; circulating a heat conducting medium; transferring a portion of the heat from the flow of hot gas to the circulating heat conducting medium for subsequent transfer to an area to be heated; and using the kinetic energy in delivering the flow of combustible fuel and air and in circulating the heat conducting medium.

23. The method of claim 22 including the further step of converting the kinetic energy extracted from the flow of hot gas by the rotating turbine wheel into electrical energy.

24. The method of claim 23 including the further step of using the electrical energy in circulating the heat conducting medium.

25. The method of claim 23 including the further step of storing the electrical energy, and using the electrical energy to start operation of the heating system.

26. The method of claim 22 including the further step of extracting a further portion of the energy of the hot gas and preheating the air flowing to the fuel burner.

27. The method of claim 22 including the further step of extracting a further portion of the energy from the hot gas and preheating the fuel flowing to the fuel burner.

28. The method of claim 22 including the further step of generating electrical energy in operation of the heating system.

29. The method of claim 28 wherein the electrical energy is generated by a thermo-electric module from heat generated in burning the mixture of fuel and air.

30. The method of claim 22 including the further step of generating electrical energy by a battery and a photo-electric cell. AMENDED CLAIMS

[recei \ ed by the International Bureau on 17 March 1999 ( 17 03 99). original claims 1 , 1 1 and 22 amended . new claims 31 -34 added . remaining claims unchanged (5 pages)] 1 A self-sustainable heating system, comprising- first means for burning a fuel and generating heat therefrom; second means connected with said first means for exhausting byproducts of the burning of said first means; third means for transferring a portion of the heat from the exnausting by-products of said first means to a heat conveying fluid; fourth means for circulating said heat conveying fluid for subsequent transfer of heat from said heat conveying fluid to a space to be heated; and fifth means, comprising a turbine in communication with said second means for extracting energy from the exhausting by-products of said first means and for operating said first means and said fourth means.

2. The heating system of claim 1 wherein the heat conveying fluid is water.

3. The heating system of claim 1 wherein the heat conveying fluid is air.

4 The heating system of claim 1 wherein the turbine is part of a turbo- machine including a compressor, and the compressor supplies combustion air to the first means

5. The heating system of claim 1 wherein said turbine is connected to and drives a motor-generator and said motor-generator operates the fourth means

7 The heating system of claim 6 wherein said sixth means comprises a motor-generator connected to said fifth means and a battery to drive said motor- generator and fifth means.

1 1 . In a space heating system including a fuel pump, a fuel burner, a burner exhaust, a heat exchanger for heating a fluid, and means for circulating the heating fluid, the improvement comprising means for self-sustainable operation of the space heating system including turbine means driven from the burner exhaust for operating the fuel pump, fuel burner, and means for circulating the heating fluid.

12. The improvement of claim 1 1 wherein the heating fluid is liquid and the means for circulating the heating fluid is a liquid pump.

13. The improvement of claim 1 1 wherein the heating fluid is air and the means for circulating the heating fluid is an air blower.

14. The improvement of claim 1 1 wherein the turbine means drives a compressor for supplying combustion air to the fuel burner.

1 5. The improvement of claim 1 1 wherein the heating system includes an electric battery, and the turbine means is connected with a motor-generator that is connected with the electric battery and is driven by the motor-generator to start operation of the heating system.

1 6. The improvement of claim 1 5 wherein the turbine means drives the motor-generator and the motor-generator recharges the electric battery while the heating system is in operation.

17. The improvement of claim 1 1 further comprising means for providing power to start said heating system.

1 8. The improvement of claim 1 7 wherein said means for providing power comprises an electric battery.

19. The improvement of claim 1 8 wherein said means for providing power further comprises an auxiliary power means.

20. The improvement of claim 1 9 wherein said auxiliary power means comprises one or more thermo-electric modules.

21 . The improvement of claim 1 9 wherein said auxiliary power means comprises one or more photo-electric cells.

22. A method of self-sustained operation of a heating system comprising delivering a flow of combustible fuel and air to a fuel burner; burning a mixture of fuel and air and generating a flow of hot gas; extracting a portion of the energy from the flow of hot gas in a rotating turbine wheel as kinetic energy; circulating a heat conducting medium through a space to be heated; transferring a portion of the heat from the flow of hot gas to the circulating heat conducting medium for subsequent transfer to the space to be heated; and using the kinetic energy in delivering the flow of combustible fuel and air and in circulating the heat conducting medium.

31 . A self-sustainable space heating system, comprising: first means for burning a fuel and generating heat therefrom; second means connected with said first means for exhausting byproducts of the burning of said first means; third means for transferring a portion of the heat from the exhausting by-products of said first means to a heat conveying fluid; fourth means for circulating said heat conveying fiuid for subsequent transfer of heat from said heat conveying fluid to a space to be heated; fifth means, comprising a turbine in communication with said second means, for extracting energy from the exhausting by-products of said first means and for operating said first means and said fourth means; and sixth means, comprising a thermo-electric module, for providing power to at least one of said other system means.

32. A self-sustainable space heating system, comprising: first means for burning a fuel and generating heat therefrom; second means connected with said first means for exhausting byproducts of the burning of said first means; third means for transferring a portion of the heat from the exhausting by-products of said first means to a conveying fluid; fourth means for circulating said heat conveying fluid for subsequent transfer of heat from said heat conveying fluid to a space to be heated; fifth means, comprising a turbine in communication with said second means, for extracting energy from the exhausting by-products of said first means and for operating said first means and said fourth means; and sixth means, comprising photo-electric means, for providing power to at least one of said other system means.

33. In a heating system including a fuel pump, a fuel burner, a burner exhaust, a heat exchanger for heating a fluid, and means for circulating the heating fluid, the improvement comprising turbine means driven from the burner exhaust for operating at least one of the fuel pump, fuel burner, and means for circulating the heating fluid, and auxiliary power means comprising one or more thermo-electric modules.

34. In a heating system including a fuel pump, a fuel burner, a burner exhaust, a heat exchanger for heating a fluid, and means for circulating the heating fluid, the improvement comprising turbine means driven from the burner exhaust for operating at least one of the fuel pump, fuel burner, and means for circulating the heating fluid, and auxiliary power means comprising one or more photo-electric modules.