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WO2007114589A1 - Method and apparatus for generating steam - Google Patents

Method and apparatus for generating steam Download PDF

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Publication number
WO2007114589A1
WO2007114589A1 PCT/KR2007/001547 KR2007001547W WO2007114589A1 WO 2007114589 A1 WO2007114589 A1 WO 2007114589A1 KR 2007001547 W KR2007001547 W KR 2007001547W WO 2007114589 A1 WO2007114589 A1 WO 2007114589A1
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WO
WIPO (PCT)
Prior art keywords
pressure
gas
steam
pressure container
water
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/KR2007/001547
Other languages
French (fr)
Inventor
Guk-Hyun Cho
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Unibell Co Ltd
Original Assignee
Unibell Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Unibell Co Ltd filed Critical Unibell Co Ltd
Publication of WO2007114589A1 publication Critical patent/WO2007114589A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B1/00—Methods of steam generation characterised by form of heating method
    • F22B1/28—Methods of steam generation characterised by form of heating method in boilers heated electrically
    • F22B1/287—Methods of steam generation characterised by form of heating method in boilers heated electrically with water in sprays or in films
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B1/00—Methods of steam generation characterised by form of heating method
    • F22B1/02—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers
    • F22B1/18—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines
    • F22B1/1853—Methods of steam generation characterised by form of heating method by exploitation of the heat content of hot heat carriers the heat carrier being a hot gas, e.g. waste gas such as exhaust gas of internal-combustion engines coming in direct contact with water in bulk or in sprays
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22B—METHODS OF STEAM GENERATION; STEAM BOILERS
    • F22B3/00—Other methods of steam generation; Steam boilers not provided for in other groups of this subclass
    • F22B3/08—Other methods of steam generation; Steam boilers not provided for in other groups of this subclass at critical or supercritical pressure values
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22—STEAM GENERATION
    • F22D—PREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
    • F22D5/00—Controlling water feed or water level; Automatic water feeding or water-level regulators
    • F22D5/26—Automatic feed-control systems
    • Y—GENERAL 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
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P80/00—Climate change mitigation technologies for sector-wide applications
    • Y02P80/10—Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier
    • Y02P80/15—On-site combined power, heat or cool generation or distribution, e.g. combined heat and power [CHP] supply

Definitions

  • the present invention relates to a method for generating high-pressure steam that is essential in industrial fields and an apparatus suitable for the method, and more particularly, to a method and apparatus for generating high-temperature steam, wherein the steam for use in industrial fields can be more efficiently and economically generated.
  • Such a conventional method for generating steam employs a phenomenon by which water in a liquid phase is vaporized into gaseous water vapor through phase change at about 100 0 C under the atmospheric pressure and the temperature of the gaseous water vapor is raised due to an increase in the internal energy of the gaseous water vapor when the gaseous water vapor exists under high pressure.
  • the conventional method for generating steam has a disadvantage in that a large-sized boiler should be equipped to generate water vapor, resulting in increased investment costs.
  • the conventional method for generating steam in view of safety, facilities such as a boiler that actually generate water vapor are installed at locations far away from places where the water vapor are to be actually used. Thus, a lot of utility facilities including pipe lines are required to carry the generated water vapor to the places where the water vapor are to be actually used. Therefore, the conventional method for generating steam has problems in that high maintenance costs in addition to the high investment costs are required, leading to increase of steam generation costs.
  • a conventional method for generating steam has inherent problems in that a small amount of steam is generated for input energy, a greater amount of energy is required when steam with a temperature higher than a typical temperature is needed, and it is not possible to obtain steam with an ultra-high temperature of 200 0 C or more.
  • an object of the present invention is to provide a method for efficiently generating high-temperature steam, wherein input energy is absorbed more efficiently into micro water particles to greatly improve the amount of water vapor for use in industrial fields and to further increase the temperature of the water vapor.
  • another object of the present invention is to provide an apparatus for efficiently generating high-temperature steam, wherein input energy is absorbed more efficiently into micro water particles to greatly improve the amount of water vapor for use in industrial fields and to further increase the temperature of the water vapor.
  • the present invention is directed to a method for generating high-temperature steam and an apparatus suitable for the method.
  • a method for generating high-pressure steam comprises the steps of: supplying any one gas selected from the group consisting of air, an inert gas, and compressed gases thereof into a high-pressure container, and increasing an internal temperature of the high-pressure container to place the gas in the high-pressure container under high pressure and temperature conditions; and supplying water from the outside and spraying the water in the high-pressure container when the conditions of the gas in the high-pressure container reach predetermined pressure and temperature conditions.
  • the high pressure of the gas in the high-pressure container into about 5 kgf/crf or more. Furthermore, it is desirable to convert the temperature of the gas in the high-pressure container into about 12O 0 C or more.
  • an apparatus for generating high-pressure steam comprises a gas supplier for supplying any one gas selected from the group consisting of air, an inert gas, and compressed gases thereof; a high-pressure container connected to the gas supplier and having an inlet through which the gas is supplied from the gas supplier, a body for containing the gas supplied through the inlet therein, and an outlet through which the gas is discharged from the inside to the outside of the body; a heat supply unit for supplying high-temperature heat into the high-pressure container; a water supply pump positioned outside of the high-pressure container to supply external water into the high-pressure container; and a spray nozzle for spraying water supplied from the water supply pump within the high-pressure container.
  • thermal efficiency can be maximized and productivity can be improved since steam is obtained by bringing input heat into direct contact with micro waterdrops.
  • the present invention has advantages in that since there is no need for use of a boiler with large capacity and thus fossil fuel is not used, a problem of environmental pollution can be solved and energy can be saved due to maximization of thermal efficiency.
  • Fig. 1 is a schematic view showing an apparatus for efficiently generating steam according to the present invention.
  • Fig. 2 shows a specific embodiment of the apparatus for generating steam according to the present invention.
  • Fig. 3 shows an embodiment in which the apparatuses for generating steam according to the present invention are connected to one another in parallel or in series.
  • an external gas is first supplied into a high-pressure container.
  • the gas is preferably air or inert gas, which can be maintained in a stable state even at high temperature and pressure.
  • the inert gas is nitrogen gas.
  • the high-pressure container have an inlet through which the gas is introduced, a cylindrical body capable of storing the gas therein, and an outlet through which the gas is discharged.
  • the high-pressure container is heated to heat the gas contained therein.
  • the gas stored in a sealed state within the high-pressure container receives thermal energy from the high-pressure container, the internal energy of the gas is gradually increased.
  • the high- pressure container gradually converts the internal temperature and pressure of the gas within itself.
  • the final internal temperature and pressure of the gas vary according to the temperature and pressure of an initially supplied gas, the conversion is preferably made such that the final pressure is about 5 kgf/cin 2 or more and the final temperature is about 12O 0 C or more.
  • the final pressure be about 10 kgf/cnf or more or the final temperature be about 200 0 C or more.
  • the predetermined high pressure refers to about 5 kg/cnf or more as a pressure that is increased as compared with the pressure of an initially supplied gas
  • the predetermined high temperature refers to about 12O 0 C or more as a temperature that is increased as compared with the temperature of the initially supplied gas.
  • the final pressure be about 10 kgf/c ⁇ f or more, or the final temperature be about 200 0 C or more. The reason is that as the final pressure or the final temperature of the gas within the container is higher, the quality of finally generated steam becomes better.
  • the water supplied from the outside is sprayed within the high-pressure container when the internal pressure or temperature of the high-pressure container reaches a predetermined condition.
  • the water is preferably sprayed into the high-pressure container through a spray nozzle.
  • the water sprayed through the spray nozzle is atomized into fine particles that in turn are exposed to the internal condition of the high- pressure container as they are.
  • the fine particles of the water receive high-temperature heat from the high-pressure container through entire surfaces of the particles and are instantaneously vaporized into gas molecules and rapidly expanded, so that they are converted into a high-pressure gas within the hermetic high-pressure container. Due to the expansion and conversion the fine particles of the water, the interior of the high-pressure container is instantaneously filled with water vapor of high temperature and pressure, i.e. high-quality water vapor.
  • Fig. 1 is a schematic view showing a steam-generating apparatus 100 according to the present invention.
  • the steam-generating apparatus 100 of the present invention includes a gas supplier 110 for supplying any one gas selected from the group consisting of air, an inert gas and compressed gases thereof.
  • the gas supplier 110 may be a compressor for directly compressing air and supplying the compressed air, or a high- pressure tank filled with pre-compressed air or inert gas.
  • air is suitable for low-pressure compression
  • the inert gas is suitable for high-pressure compression.
  • the inert gas is more preferable in view of safety of the apparatus.
  • Nitrogen gas is most suitably used as the inert gas.
  • the steam-generating apparatus 100 of the present invention includes a high- pressure container 120 connected to the gas supplier 110.
  • the high-pressure container 120 provides a space in which water vapor of high temperature and pressure is to be generated through heat exchange between molecules of the gas and water that are supplied into the high-pressure container.
  • the high-pressure container 120 is preferably a cylindrical container for use in industrial fields.
  • the high-pressure container 120 includes an inlet 122 through which the gas can be supplied into the high-pressure container 120 by the gas supplier 110.
  • the high-pressure container 120 further includes a body 124 defining the space in which heat exchange can be made between the molecules of the gas and water.
  • the high-pressure container includes an outlet 126 through which gases in the high-pressure container 120 are discharged to the outside.
  • the steam-generating apparatus 100 of the present invention includes a heat supply unit 130 for supplying thermal energy into the high-pressure container 120.
  • the heat supply unit 130 is preferably a heater band attached and wound on an outer surface of the body 124 and may be a pipe using a heat medium.
  • the heat supply unit 130 converts electrical energy into thermal energy so as to supply high-temperature heat to the body 124 of the high-pressure container 120.
  • the internal energy of the gas i.e., air or inert gas
  • the volume of the body 124 of the high-pressure container 120 is constant, both the pressure and temperature of the gas are naturally increased.
  • the internal condition of the high- pressure container 120 may vary depending on the pressure and temperature of the initially supplied gas, it is preferred that the final pressure be about 5 kgf/c ⁇ f or more and the final temperature be about 12O 0 C or more if the gas is supplied at a lowest pressure and temperature.
  • the steam-generating apparatus 100 of the present invention includes a water supply pump 140 for supplying water from the outside of the high-pressure container 120 into the high-pressure container 120.
  • the water supply pump 140 is preferably a water pump or a water booster capable of supplying water at high pressure.
  • the reason is that the gas supplied into the high-pressure container 120 is under a high-temperature and pressure condition, and thus, water should be supplied into the high-pressure container 120 at a pressure higher than the internal pressure of the high-pressure container 120.
  • the water is preferably purified water or industrial water.
  • the water supplied from the outside is used as a material for generating steam within the high-pressure container 120. As the internal pressure of the high-pressure container 120 is higher, the internal temperature of the high-pressure container 120 is increased.
  • the steam-generating apparatus 100 of the present invention includes a spray nozzle 150 for spraying the water supplied from the water supply pump 140 into the high- pressure container 120.
  • the spray nozzle 150 is to spray the water, which is supplied from the water supply pump 140, in the form of fine waterdrops within the high-pressure container 120.
  • the fine waterdrops sprayed from the spray nozzle 150 are in an environment of high temperature and pressure as soon as the fine waterdrops are sprayed from the spray nozzle 150.
  • the environment of high temperature and pressure is formed by the gas (air or inert gas) that has received the high-temperature heat within the high- pressure container 120.
  • the fine waterdrops absorb high-temperature thermal energy through all surfaces of the fine waterdrops in the environment of high temperature and pressure. Therefore, the internal energy of the fine waterdrops sprayed from the spray nozzle 150 is increased instantaneously and rapidly, and the volumes of the waterdrops are rapidly expanded while being converted into gas molecules or water vapors. Accordingly, the high-pressure container 120 generates a large amount of steam within a very short period of time. Since the volume of the steam is instantaneously increased, steam of ultrahigh pressure is generated within a limited space, and at the same time, steam of ultra-high temperature is also generated.
  • FIG. 2 more specifically shows a steam-generating apparatus 100 as the preferred embodiment of the present invention.
  • a cylinder with a length of 1200 mm and a volume of 40 liters is selected.
  • a heater band as a heat supply unit 130 is installed on an outer surface of the cylinder.
  • a gas-supplying pipe 10 is connected to a lower side of the high-pressure container 120, and a high-pressure tank as a gas supplier, which is filled with compressed air, is connected to the gas-supplying pipe 10.
  • a compressed air valve 12 capable of controlling the amount of the compressed air to be supplied is installed on the gas- supplying pipe 10, and a check valve 14 for preventing a backflow of steam contained in the cylinder is installed on the gas-supplying pipe 10.
  • a water supply pipe 20 for supplying water from the outside into the cylinder is connected to an upper portion of the cylinder, and a water booster as a water supply pump 140 is installed on the water supply pipe 20. Furthermore, a water valve 22 capable of controlling the amount of water to be supplied is installed on the water supply pipe 20, and a check valve 24 for preventing a backflow of water due to steam contained in the cylinder is installed on the water supply pipe 20.
  • a steam discharge pipe 30 for discharging steam generated in the cylinder to the outside is installed on at the upper portion of the cylinder, and a steam valve 32 capable of controlling the amount of steam to be discharged is installed on the steam discharge pipe 30. Further, a temperature-measuring sensor 166 capable of measuring the internal temperature of a gas within the cylinder and a pressure-measuring sensor 168 capable of measuring the internal pressure of the gas within the cylinder are installed on the cylinder.
  • the valve 12 is opened to supply compressed air of 5 kgf/cnf into the cylinder.
  • water is compressed to a pressure of 250 kgf/cnf by the water booster and then sprayed in the cylinder by opening the water valve 22.
  • the internal pressure of the cylinder starts to rise as the water is sprayed, and it takes about 30 seconds for the oressure of steam to reach 30 kgf/c ⁇ f.
  • the temperature of steam within the cylinder tends to be slightly lowered when the water is sprayed and water vapor is generated.
  • the temperature of steam within the cylinder tends to be increased again while the supply of the water by the water booster is interrupted for a moment and the spraying of the water is stopped. For instance, if the pressure of the steam within the cylinder is lowered to 28 kgf/cin 2 , the pressure of the steam within the cylinder is increased to 34 kgf/ ⁇ if or more and the temperature of the steam is increased to 300 0 C or more during a waiting time of about 10 seconds after closing the water valve 22. In order to use the steam generated within the cylinder, the steam is discharged until the internal pressure of the cylinder is lowered to 10 kgf/c ⁇ f by opening the steam valve 32. At this time, the internal temperature of the cylinder is lowered from 300 0 C to
  • the cylinder can generate a large amount of high-temperature steam by repeating the aforementioned processes.
  • a case where a high-pressure inert gas is used will be described as follows.
  • the aforementioned cylinder is used as a high-pressure container 120, a heater band as a heat supply unit 130 is installed on an outer wall of the cylinder, and nitrogen gas is used as the inert gas.
  • the nitrogen gas is supplied into the cylinder at a pressure of 18 kgf/cin 2 by using a compressor as a gas supplier 110, and the temperature of the cylinder is increased to about 37O 0 C through heating. In this state, the internal pressure of the cylinder is increased to about 21 kgf/cnf. At this time, water is sprayed through a spray nozzle 150.
  • Water vapor is immediately generated within the cylinder, and the pressure of the cylinder is increased accordingly. Since the internal pressure of the cylinder is maintained in a high-pressure condition, the water should be supplied at a pressure higher than the internal pressure of the cylinder.
  • a water booster is used as a water supply pump 140, and the water is sprayed at a constant pressure after the water is compressed and then stored in a storage container 142.
  • a spraying time of about 70 seconds elapses, the pressure of a mixture of the nitrogen gas and the water vapor is increased to 30 kgf/cin 2 .
  • a large amount of steam can be efficiently generated by connecting a plurality of high-pressure containers 120 to one another.
  • Fig. 3 exemplarily shows five high-pressure containers 120 connected to one another as a further embodiment of the present invention. This embodiment prevents a phenomenon by which if only one high-pressure container 120 is used and steam generated in the high-pressure container 120 is completely discharged, steam cannot be supplied instantaneously while steam is generated again in a subsequent process.
  • This embodiment employs the high-pressure containers 120 each of which is substantially identical with the high-pressure container of the previous embodiment, except particularly limited details described below:
  • the high-pressure containers 120 are arranged such that upper and lower portions of the high-pressure containers are connected in parallel to each other, and pairs of the high-pressure containers 120 are connected to each other in series as a whole.
  • a heater band as a heat supply unit 130 is installed on an outer surface of each of the high-pressure containers 120, a water supply pipe 20 is installed on an upper portion of each of the high-pressure containers 120, and a spray nozzle 150 is connected to an end of the water supply pipe.
  • the spray nozzle 150 is deeply installed along a central axis of the high-pressure container 120 so as to be heated in the high-pressure container, so that the water can be preheated to a certain extent in a process of supplying the water into the spray nozzle from the outside and spraying the water.
  • the levels of the pipes are adjusted by forming the pipes in a "U" shape such that the pipes are bent toward intermediate portions of the cylinders.
  • This is to use a pressure difference between a preceding high-pressure container 120 and a subsequent high-pressure container 120 connected thereto. That is, when a lead time for generating steam within the high-pressure containers 120 is prolonged, a pressure interference effect due to the varying levels of the pipes allows a desired pressure to be maintained in a preceding high-pressure container 120 even though steam is discharged through an outlet, thereby continuously generating and supplying steam.
  • Steam of high temperature and pressure obtained according to the present invention can be widely used as various kinds of heat media in industrial fields.
  • the high-temperature and high-pressure of steam can be produced by simple facilities.
  • steam of high temperature and pressure can be more sufficiently obtained by spraying water under conditions where the internal temperatures and pressures of the high-pressure containers are maintained at high temperature and pressure.

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Abstract

The present invention relates to a method for generating high-pressure steam that is essential in industrial fields and an apparatus suitable for the method. A method for generating high-pressure steam according to the present invention comprises the steps of: compressing an external gas into a high-pressure gas and supplying the high-pressure gas into a high-pressure container, and increasing an internal temperature of the high-pressure container to establish certain pressure and temperature conditions within the high-pressure container; and supplying water from the outside to the high-pressure container and spraying the water within the high-pressure container when internal conditions of the high-pressure container reach predetermined pressure and temperature conditions, thereby generating steam. According to the present invention, it is possible to more efficiently and economically generate steam for use in industrial fields.

Description

METHOD AND APPARATUS FOR GENERATING STEAM
Technical Field
The present invention relates to a method for generating high-pressure steam that is essential in industrial fields and an apparatus suitable for the method, and more particularly, to a method and apparatus for generating high-temperature steam, wherein the steam for use in industrial fields can be more efficiently and economically generated.
Background Art
In order to obtain steam of high temperature and pressure in industrial fields, industrial water is generally heated in a boiler at high temperature and pressure to generate the steam of high temperature and pressure. It has been found that steam ordinarily obtained by means of such a conventional method has a temperature of about 14O0C and is maintained at a pressure of about 12kgf/citf , whereas better-quality steam required depending on industrial fields has a temperature of about 18O0C and is maintained at a pressure of about 15kgf/cin2.
Such a conventional method for generating steam employs a phenomenon by which water in a liquid phase is vaporized into gaseous water vapor through phase change at about 1000C under the atmospheric pressure and the temperature of the gaseous water vapor is raised due to an increase in the internal energy of the gaseous water vapor when the gaseous water vapor exists under high pressure.
However, since water in a liquid phase is heated as it is by using a boiler in such a conventional method for generating steam, a large amount of heat should be applied from the outside to the water so as to vaporize the water in the boiler. This means that the entire water contained in the boiler should be heated to be vaporized and resulting water vapor should be further heated to a desired temperature in order to generate steam. Therefore, the conventional method for generating steam has disadvantages in that an excessive amount of energy should be input and the amount of generated steam is small for the amount of input energy.
Moreover, although a large amount of energy is supplied into the boiler in the conventional method, most of the supplied energy continuously vaporizes water contained in the boiler to generate water vapor, so that it is not possible to further raise the temperature of the generated water vapor. Thus, there are disadvantages in that the temperature of the generated water vapor is limited to about 18O0C and it is not possible to obtain water vapor of a temperature higher than 18O0C.
In addition, the conventional method for generating steam has a disadvantage in that a large-sized boiler should be equipped to generate water vapor, resulting in increased investment costs.
Furthermore, according to the conventional method for generating steam, in view of safety, facilities such as a boiler that actually generate water vapor are installed at locations far away from places where the water vapor are to be actually used. Thus, a lot of utility facilities including pipe lines are required to carry the generated water vapor to the places where the water vapor are to be actually used. Therefore, the conventional method for generating steam has problems in that high maintenance costs in addition to the high investment costs are required, leading to increase of steam generation costs.
Disclosure of Invention Technical Problem
As described above, a conventional method for generating steam has inherent problems in that a small amount of steam is generated for input energy, a greater amount of energy is required when steam with a temperature higher than a typical temperature is needed, and it is not possible to obtain steam with an ultra-high temperature of 2000C or more.
Accordingly, an object of the present invention is to provide a method for efficiently generating high-temperature steam, wherein input energy is absorbed more efficiently into micro water particles to greatly improve the amount of water vapor for use in industrial fields and to further increase the temperature of the water vapor. Moreover, another object of the present invention is to provide an apparatus for efficiently generating high-temperature steam, wherein input energy is absorbed more efficiently into micro water particles to greatly improve the amount of water vapor for use in industrial fields and to further increase the temperature of the water vapor.
Technical Solution
The present invention is directed to a method for generating high-temperature steam and an apparatus suitable for the method.
A method for generating high-pressure steam according to the present invention comprises the steps of: supplying any one gas selected from the group consisting of air, an inert gas, and compressed gases thereof into a high-pressure container, and increasing an internal temperature of the high-pressure container to place the gas in the high-pressure container under high pressure and temperature conditions; and supplying water from the outside and spraying the water in the high-pressure container when the conditions of the gas in the high-pressure container reach predetermined pressure and temperature conditions.
In the present invention, it is desirable to convert the high pressure of the gas in the high-pressure container into about 5 kgf/crf or more. Furthermore, it is desirable to convert the temperature of the gas in the high-pressure container into about 12O0C or more.
Further, an apparatus for generating high-pressure steam according to the present invention comprises a gas supplier for supplying any one gas selected from the group consisting of air, an inert gas, and compressed gases thereof; a high-pressure container connected to the gas supplier and having an inlet through which the gas is supplied from the gas supplier, a body for containing the gas supplied through the inlet therein, and an outlet through which the gas is discharged from the inside to the outside of the body; a heat supply unit for supplying high-temperature heat into the high-pressure container; a water supply pump positioned outside of the high-pressure container to supply external water into the high-pressure container; and a spray nozzle for spraying water supplied from the water supply pump within the high-pressure container.
Advantageous Effects Upon use of the apparatus for generating steam according to the present invention, there is an advantage in that steam in a wide temperature range can be obtained.
In addition, upon use of the apparatus for generating steam according to the present invention, there is an advantage in that steam with an ultra-high temperature (e.g., 2000C or more) that has not been obtainable by means of a conventional method.
Furthermore, upon use of the apparatus for generating steam according to the present invention, facility costs can be greatly reduced since there is no need for use of a boiler with large capacity.
Moreover, upon use of the apparatus for generating steam according to the present invention, thermal efficiency can be maximized and productivity can be improved since steam is obtained by bringing input heat into direct contact with micro waterdrops.
Further, the present invention has advantages in that since there is no need for use of a boiler with large capacity and thus fossil fuel is not used, a problem of environmental pollution can be solved and energy can be saved due to maximization of thermal efficiency.
Brief Description of Drawings
Fig. 1 is a schematic view showing an apparatus for efficiently generating steam according to the present invention.
Fig. 2 shows a specific embodiment of the apparatus for generating steam according to the present invention.
Fig. 3 shows an embodiment in which the apparatuses for generating steam according to the present invention are connected to one another in parallel or in series.
Best Mode Hereinafter, the present invention will be described in greater detail as follows.
In a method for generating high-temperature steam according to the present invention, an external gas is first supplied into a high-pressure container. The gas is preferably air or inert gas, which can be maintained in a stable state even at high temperature and pressure. Most preferably, the inert gas is nitrogen gas. Furthermore, it is preferred that the high-pressure container have an inlet through which the gas is introduced, a cylindrical body capable of storing the gas therein, and an outlet through which the gas is discharged.
In the method for generating high-temperature steam according to the present invention, the high-pressure container is heated to heat the gas contained therein. As the gas stored in a sealed state within the high-pressure container receives thermal energy from the high-pressure container, the internal energy of the gas is gradually increased. The high- pressure container gradually converts the internal temperature and pressure of the gas within itself. Although the final internal temperature and pressure of the gas vary according to the temperature and pressure of an initially supplied gas, the conversion is preferably made such that the final pressure is about 5 kgf/cin2 or more and the final temperature is about 12O0C or more. However, in order to generate high-quality steam, it is preferred that the final pressure be about 10 kgf/cnf or more or the final temperature be about 2000C or more. As the final pressure or final temperature of the gas within the high- pressure container is higher, the quality of finally generated steam becomes better. In the method for generating high-temperature steam according to the present invention, water is supplied into the high-pressure container from the outside when an internal condition of the gas reaches a predetermined high pressure or temperature. In the present invention, the predetermined high pressure refers to about 5 kg/cnf or more as a pressure that is increased as compared with the pressure of an initially supplied gas, and the predetermined high temperature refers to about 12O0C or more as a temperature that is increased as compared with the temperature of the initially supplied gas. However, in order to generate high-quality steam, it is preferred that the final pressure be about 10 kgf/cπf or more, or the final temperature be about 2000C or more. The reason is that as the final pressure or the final temperature of the gas within the container is higher, the quality of finally generated steam becomes better.
In the method for generating high-temperature steam according to the present invention, the water supplied from the outside is sprayed within the high-pressure container when the internal pressure or temperature of the high-pressure container reaches a predetermined condition. The water is preferably sprayed into the high-pressure container through a spray nozzle. At this time, the water sprayed through the spray nozzle is atomized into fine particles that in turn are exposed to the internal condition of the high- pressure container as they are. The fine particles of the water receive high-temperature heat from the high-pressure container through entire surfaces of the particles and are instantaneously vaporized into gas molecules and rapidly expanded, so that they are converted into a high-pressure gas within the hermetic high-pressure container. Due to the expansion and conversion the fine particles of the water, the interior of the high-pressure container is instantaneously filled with water vapor of high temperature and pressure, i.e. high-quality water vapor.
Hereinafter, the present invention will be described in greater detail in connection with specific embodiments.
The method for generating high-temperature steam according to the present invention can be described in a more specific and detailed manner through an apparatus for generating steam 100 explained below. However, it will be apparent that the accompanying drawings are only to specifically illustrate embodiments of the present invention and the technical spirit of the present invention is not limited thereto.
Fig. 1 is a schematic view showing a steam-generating apparatus 100 according to the present invention.
The steam-generating apparatus 100 of the present invention includes a gas supplier 110 for supplying any one gas selected from the group consisting of air, an inert gas and compressed gases thereof. In the present invention, the gas supplier 110 may be a compressor for directly compressing air and supplying the compressed air, or a high- pressure tank filled with pre-compressed air or inert gas. In the present invention, among gases to be supplied by the gas supplier 110, air is suitable for low-pressure compression, whereas the inert gas is suitable for high-pressure compression. In case of high-pressure compression, the inert gas is more preferable in view of safety of the apparatus. Nitrogen gas is most suitably used as the inert gas.
The steam-generating apparatus 100 of the present invention includes a high- pressure container 120 connected to the gas supplier 110. The high-pressure container 120 provides a space in which water vapor of high temperature and pressure is to be generated through heat exchange between molecules of the gas and water that are supplied into the high-pressure container. The high-pressure container 120 is preferably a cylindrical container for use in industrial fields. The high-pressure container 120 includes an inlet 122 through which the gas can be supplied into the high-pressure container 120 by the gas supplier 110. The high-pressure container 120 further includes a body 124 defining the space in which heat exchange can be made between the molecules of the gas and water. In addition, the high-pressure container includes an outlet 126 through which gases in the high-pressure container 120 are discharged to the outside.
The steam-generating apparatus 100 of the present invention includes a heat supply unit 130 for supplying thermal energy into the high-pressure container 120. The heat supply unit 130 is preferably a heater band attached and wound on an outer surface of the body 124 and may be a pipe using a heat medium. The heat supply unit 130 converts electrical energy into thermal energy so as to supply high-temperature heat to the body 124 of the high-pressure container 120. When the high-temperature heat is transferred to the high-pressure container 120 by the heat supply unit 130, the internal energy of the gas (i.e., air or inert gas) within the high-pressure container 120 is increased. Since the volume of the body 124 of the high-pressure container 120 is constant, both the pressure and temperature of the gas are naturally increased. Although the internal condition of the high- pressure container 120 may vary depending on the pressure and temperature of the initially supplied gas, it is preferred that the final pressure be about 5 kgf/cπf or more and the final temperature be about 12O0C or more if the gas is supplied at a lowest pressure and temperature.
The steam-generating apparatus 100 of the present invention includes a water supply pump 140 for supplying water from the outside of the high-pressure container 120 into the high-pressure container 120. The water supply pump 140 is preferably a water pump or a water booster capable of supplying water at high pressure. The reason is that the gas supplied into the high-pressure container 120 is under a high-temperature and pressure condition, and thus, water should be supplied into the high-pressure container 120 at a pressure higher than the internal pressure of the high-pressure container 120. The water is preferably purified water or industrial water. The water supplied from the outside is used as a material for generating steam within the high-pressure container 120. As the internal pressure of the high-pressure container 120 is higher, the internal temperature of the high-pressure container 120 is increased. Further, as the internal temperature of the high-pressure container 120 is higher, sufficient thermal energy can be supplied to the water supplied from the outside. Therefore, it is possible to generate high-quality steam. The steam-generating apparatus 100 of the present invention includes a spray nozzle 150 for spraying the water supplied from the water supply pump 140 into the high- pressure container 120. The spray nozzle 150 is to spray the water, which is supplied from the water supply pump 140, in the form of fine waterdrops within the high-pressure container 120. The fine waterdrops sprayed from the spray nozzle 150 are in an environment of high temperature and pressure as soon as the fine waterdrops are sprayed from the spray nozzle 150. The environment of high temperature and pressure is formed by the gas (air or inert gas) that has received the high-temperature heat within the high- pressure container 120.
In present invention, the fine waterdrops absorb high-temperature thermal energy through all surfaces of the fine waterdrops in the environment of high temperature and pressure. Therefore, the internal energy of the fine waterdrops sprayed from the spray nozzle 150 is increased instantaneously and rapidly, and the volumes of the waterdrops are rapidly expanded while being converted into gas molecules or water vapors. Accordingly, the high-pressure container 120 generates a large amount of steam within a very short period of time. Since the volume of the steam is instantaneously increased, steam of ultrahigh pressure is generated within a limited space, and at the same time, steam of ultra-high temperature is also generated.
A preferred embodiment of the present invention will be described in greater detail as follows. Fig. 2 more specifically shows a steam-generating apparatus 100 as the preferred embodiment of the present invention.
As a high-pressure container 120 used in the steam-generating apparatus 100 of the present invention, a cylinder with a length of 1200 mm and a volume of 40 liters is selected. A heater band as a heat supply unit 130 is installed on an outer surface of the cylinder. A gas-supplying pipe 10 is connected to a lower side of the high-pressure container 120, and a high-pressure tank as a gas supplier, which is filled with compressed air, is connected to the gas-supplying pipe 10. A compressed air valve 12 capable of controlling the amount of the compressed air to be supplied is installed on the gas- supplying pipe 10, and a check valve 14 for preventing a backflow of steam contained in the cylinder is installed on the gas-supplying pipe 10.
Meanwhile, a water supply pipe 20 for supplying water from the outside into the cylinder is connected to an upper portion of the cylinder, and a water booster as a water supply pump 140 is installed on the water supply pipe 20. Furthermore, a water valve 22 capable of controlling the amount of water to be supplied is installed on the water supply pipe 20, and a check valve 24 for preventing a backflow of water due to steam contained in the cylinder is installed on the water supply pipe 20. A steam discharge pipe 30 for discharging steam generated in the cylinder to the outside is installed on at the upper portion of the cylinder, and a steam valve 32 capable of controlling the amount of steam to be discharged is installed on the steam discharge pipe 30. Further, a temperature-measuring sensor 166 capable of measuring the internal temperature of a gas within the cylinder and a pressure-measuring sensor 168 capable of measuring the internal pressure of the gas within the cylinder are installed on the cylinder.
In such a configuration, the valve 12 is opened to supply compressed air of 5 kgf/cnf into the cylinder. In a process of supplying power to the heater band to increase the temperature of air within the cylinder to 3000C, water is compressed to a pressure of 250 kgf/cnf by the water booster and then sprayed in the cylinder by opening the water valve 22. At this time, the internal pressure of the cylinder starts to rise as the water is sprayed, and it takes about 30 seconds for the oressure of steam to reach 30 kgf/cπf. The temperature of steam within the cylinder tends to be slightly lowered when the water is sprayed and water vapor is generated. However, the temperature of steam within the cylinder tends to be increased again while the supply of the water by the water booster is interrupted for a moment and the spraying of the water is stopped. For instance, if the pressure of the steam within the cylinder is lowered to 28 kgf/cin2, the pressure of the steam within the cylinder is increased to 34 kgf/αif or more and the temperature of the steam is increased to 3000C or more during a waiting time of about 10 seconds after closing the water valve 22. In order to use the steam generated within the cylinder, the steam is discharged until the internal pressure of the cylinder is lowered to 10 kgf/cπf by opening the steam valve 32. At this time, the internal temperature of the cylinder is lowered from 3000C to
22O0C. Then, the steam valve 32 is closed to stop the discharge of the steam. The internal temperature of the cylinder starts to rise again.
The cylinder can generate a large amount of high-temperature steam by repeating the aforementioned processes.
As another embodiment of the present invention, a case where a high-pressure inert gas is used will be described as follows. The aforementioned cylinder is used as a high-pressure container 120, a heater band as a heat supply unit 130 is installed on an outer wall of the cylinder, and nitrogen gas is used as the inert gas. The nitrogen gas is supplied into the cylinder at a pressure of 18 kgf/cin2 by using a compressor as a gas supplier 110, and the temperature of the cylinder is increased to about 37O0C through heating. In this state, the internal pressure of the cylinder is increased to about 21 kgf/cnf. At this time, water is sprayed through a spray nozzle 150. Water vapor is immediately generated within the cylinder, and the pressure of the cylinder is increased accordingly. Since the internal pressure of the cylinder is maintained in a high-pressure condition, the water should be supplied at a pressure higher than the internal pressure of the cylinder. In order to constantly maintain the pressure of the supplied water and to spray the supplied water uniformly, a water booster is used as a water supply pump 140, and the water is sprayed at a constant pressure after the water is compressed and then stored in a storage container 142. When a spraying time of about 70 seconds elapses, the pressure of a mixture of the nitrogen gas and the water vapor is increased to 30 kgf/cin2. Furthermore, as a further embodiment of the present invention, a large amount of steam can be efficiently generated by connecting a plurality of high-pressure containers 120 to one another.
Fig. 3 exemplarily shows five high-pressure containers 120 connected to one another as a further embodiment of the present invention. This embodiment prevents a phenomenon by which if only one high-pressure container 120 is used and steam generated in the high-pressure container 120 is completely discharged, steam cannot be supplied instantaneously while steam is generated again in a subsequent process.
This embodiment employs the high-pressure containers 120 each of which is substantially identical with the high-pressure container of the previous embodiment, except particularly limited details described below: The high-pressure containers 120 are arranged such that upper and lower portions of the high-pressure containers are connected in parallel to each other, and pairs of the high-pressure containers 120 are connected to each other in series as a whole.
Moreover, in this embodiment, a heater band as a heat supply unit 130 is installed on an outer surface of each of the high-pressure containers 120, a water supply pipe 20 is installed on an upper portion of each of the high-pressure containers 120, and a spray nozzle 150 is connected to an end of the water supply pipe. The spray nozzle 150 is deeply installed along a central axis of the high-pressure container 120 so as to be heated in the high-pressure container, so that the water can be preheated to a certain extent in a process of supplying the water into the spray nozzle from the outside and spraying the water.
Furthermore, when the high-pressure containers 120 are connected to one another in this embodiment, the levels of the pipes are adjusted by forming the pipes in a "U" shape such that the pipes are bent toward intermediate portions of the cylinders. This is to use a pressure difference between a preceding high-pressure container 120 and a subsequent high-pressure container 120 connected thereto. That is, when a lead time for generating steam within the high-pressure containers 120 is prolonged, a pressure interference effect due to the varying levels of the pipes allows a desired pressure to be maintained in a preceding high-pressure container 120 even though steam is discharged through an outlet, thereby continuously generating and supplying steam. In this case, it is desirable to install a steam valve 32 for discharging steam only at a last high-pressure container 120.
Industrial Applicability
Steam of high temperature and pressure obtained according to the present invention can be widely used as various kinds of heat media in industrial fields. According to the present invention, the high-temperature and high-pressure of steam can be produced by simple facilities. Generally, steam of high temperature and pressure can be more sufficiently obtained by spraying water under conditions where the internal temperatures and pressures of the high-pressure containers are maintained at high temperature and pressure.
Although the method and apparatus for generating steam according to the present invention have been described in detail above, the descriptions merely illustrate the most preferred embodiments of the present invention and the present invention is not limited thereto. The scope of the present invention is defined by the appended claims. Further, it will be apparent that those skilled in the art can make various changes and modifications from the descriptions of the specification and the changes and modifications fall within the scope of the present invention.

Claims

1. A method for generating high-pressure steam, comprising the steps of: supplying a gas into a high-pressure container (120), and increasing an internal temperature of the gas within the high-pressure container (120) so that the gas is under predetermined pressure and temperature conditions; and supplying water from the outside and spraying the water in the high-pressure container (120) when the conditions of the gas in the high-pressure container (120) reach predetermined pressure and temperature conditions.
2. The method as claimed in claim 1, wherein the predetermined pressure and temperature conditions are an internal pressure of the high-pressure container of 5 kgf/cπf or more and an internal temperature of the high-pressure container of 12O0C or more.
3. The method as claimed in claim 1, wherein the predetermined pressure and temperature conditions are an internal pressure of the high-pressure container of 5 kgf/cπf or more and an internal temperature of the high-pressure container of 12O0C or more.
4. An apparatus for generating high-pressure steam, comprising: a gas supplier (110) for supplying any one gas selected from the group consisting of air, an inert gas and compressed gases thereof; a high-pressure container (120) connected to the gas supplier (110) and having an inlet through which the gas is supplied from the gas supplier, a body for containing the gas supplied through the inlet therein, and an outlet through which the gas is discharged from the inside to the outside of the body; a heat supply unit (130) for supplying high-temperature heat into the high-pressure container; a water supply pump (140) positioned outside of the high-pressure container to supply external water into the high-pressure container; and a spray nozzle (150) for spraying water supplied from the water supply pump within the high-pressure container.
5. The apparatus as claimed in claim 4, wherein the high-pressure containers (120) are arranged such that upper and lower portions of the high-pressure containers are connected in parallel to each other, and pairs of the high-pressure containers are connected to each other in series as a whole.
PCT/KR2007/001547 2006-04-03 2007-03-30 Method and apparatus for generating steam Ceased WO2007114589A1 (en)

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KR20180047993A (en) * 2016-11-02 2018-05-10 선문대학교 산학협력단 Steam generator with plural heaters
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EP4320382A4 (en) * 2022-06-06 2024-07-17 Limited Liability Company "G-Mak" FOG GENERATOR FOR A SECURITY SYSTEM

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