GB2158222A - Heated chambers for growing plants - Google Patents

Heated chambers for growing plants Download PDF

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Publication number
GB2158222A
GB2158222A GB08411479A GB8411479A GB2158222A GB 2158222 A GB2158222 A GB 2158222A GB 08411479 A GB08411479 A GB 08411479A GB 8411479 A GB8411479 A GB 8411479A GB 2158222 A GB2158222 A GB 2158222A
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GB
United Kingdom
Prior art keywords
chamber
air
heat
outside
pressure
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.)
Granted
Application number
GB08411479A
Other versions
GB2158222B (en
GB8411479D0 (en
Inventor
Nobuyoshi Kuboyama
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.)
Individual
Original Assignee
Individual
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 Individual filed Critical Individual
Priority to GB08411479A priority Critical patent/GB2158222B/en
Priority to DE19843416617 priority patent/DE3416617A1/en
Priority to FR8407564A priority patent/FR2564575A1/en
Publication of GB8411479D0 publication Critical patent/GB8411479D0/en
Publication of GB2158222A publication Critical patent/GB2158222A/en
Application granted granted Critical
Publication of GB2158222B publication Critical patent/GB2158222B/en
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24D—DOMESTIC- OR SPACE-HEATING SYSTEMS, e.g. CENTRAL HEATING SYSTEMS; DOMESTIC HOT-WATER SUPPLY SYSTEMS; ELEMENTS OR COMPONENTS THEREFOR
    • F24D5/00—Hot-air central heating systems; Exhaust gas central heating systems
    • F24D5/02—Hot-air central heating systems; Exhaust gas central heating systems operating with discharge of hot air into the space or area to be heated
    • F24D5/04—Hot-air central heating systems; Exhaust gas central heating systems operating with discharge of hot air into the space or area to be heated with return of the air or the air-heater
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F11/00—Control or safety arrangements
    • F24F11/70—Control systems characterised by their outputs; Constructional details thereof
    • F24F11/72—Control systems characterised by their outputs; Constructional details thereof for controlling the supply of treated air, e.g. its pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F24—HEATING; RANGES; VENTILATING
    • F24F—AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING
    • F24F12/00—Use of energy recovery systems in air conditioning, ventilation or screening
    • F24F12/001—Use of energy recovery systems in air conditioning, ventilation or screening with heat-exchange between supplied and exhausted air
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B23/00—Heating arrangements
    • F26B23/001—Heating arrangements using waste heat
    • F26B23/002—Heating arrangements using waste heat recovered from dryer exhaust gases
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F26—DRYING
    • F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
    • F26B5/00—Drying solid materials or objects by processes not involving the application of heat
    • F26B5/04—Drying solid materials or objects by processes not involving the application of heat by evaporation or sublimation of moisture under reduced pressure, e.g. in a vacuum
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F28—HEAT EXCHANGE IN GENERAL
    • F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
    • F28D21/00—Heat-exchange apparatus not covered by any of the groups F28D1/00 - F28D20/00
    • F28D21/0001—Recuperative heat exchangers
    • F28D21/0014—Recuperative heat exchangers the heat being recuperated from waste air or from vapors
    • 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
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
    • Y02B30/56—Heat recovery units
    • 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
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Molecular Biology (AREA)
  • Sustainable Development (AREA)
  • Drying Of Solid Materials (AREA)

Abstract

The airtight chamber 1 contains a heater 17 and a pump 12 withdraws air from the chamber via a heat exchanger A and a valve 11 to reduce the pressure in the chamber. Outlet passages 4 in the heat exchanger are provided with fins 5 and outside air is supplied to the chamber via a valve 9, the air being heated in the heat exchanger to reduce energy losses in the system. Temperature, pressure and humidity sensors 18, 19, 21 are provided in the chamber and supply signals to a controller 20. By opening a valve 16 in an intake pipe 15 the chamber may be rapidly cooled. Heating at reduced pressure assists drying of the articles such as flowers, fruit or vegetables in the chamber. <IMAGE>

Description

SPECIFICATION Heat-treating process and apparatus utilizing reduction of air pressure within a chamber This invention relates to a heat-treating process and apparatus of the kind utilizing reduction of air pressure within a chamber.
The origin of this invention is based on Japanese Unexamined Patent Publication 57-144869 (Japanese Patent Application 56-29953 filed by the present Applicant), in which air within an airtight chamber is heated by reducing the air pressure in the chamber by a suction means such as a vacuum pump and by use of a heat source such as a heater.
More specifically, by establishing a difference between the air pressure inside the chamber and the normal air pressure thereoutside while actuating an automatic valve, wet articles disposed in the airtight chamber may be heated and dried effectively. This technique may also be applied for growing plants such as flowers, vegetables, fruit, etc.
In practice, by programming in advance the air pressure reducing condition, heating temperature and heating time in view of the kind, quantity, size and water-containing state of the articles to be treated, the heating operation most suitable for respective articles to be treated may be carried out in continuous drive. Accordingly, this process may be applied to various drying and heating applications or for expediting growth of plants.
However, according to one aspect of this known process, the thermal energy of hot air within the chamber is discharged wastefully to the outside of the chamber, while cold outside air is introduced into the chamber by way of an air introducing pipe. As a result, when the hot air discharge function by way of the suction means and the cold outside air introducing function by way of the outer air introducing pipe are carried out simultaneously, the disadvantage is incurred, particularly in the winter season, that the temperature in the chamber is decreased rapidly, whereby the efficiency of the heating and drying operation is considerably reduced.
In particular, wet articles such as medical plants, marine plants, flowers, etc. may be discoloured or be caused to deteriorate in quality under the aforedescribed heating and drying operation. Furthermore, when expediting growth of plants, it becomes difficult to maintain the thermal energy in the chamber constantly. From this point of view, it is necessary to control the introduction of outside air accurately.
A further disadvantage of the known process is that additional energy cost is incurred due to the energy loss.
In accordance with the present invention there is provided a heat-treating process and apparatus utilizing reduction of air pressure within a chamber, in which cold outside air introduced into the chamber from the outside thereof is pre-heated using heated air from within the chamber by means of a heatexchange means disposed in or communicating with the airtight chamber, whereby the articles incorporated in the chamber may be heat-treated or dried effectively with no energy loss.
In accordance with one aspect of the invention there is provided a heat-treating process comprising: forcibly suctioning air from within an airtight chamber and maintaining the pressure differential between the air pressure within the chamber and the normal air pressure outside the chamber at a predetermined level; heating the air within the chamber to a predetermined temperature by a heat source disposed therewithin; discharging vapourized water from within the chamber; and heat-exchanging cold outside air introduced into the chamber from the outside thereof with thermal energy of heated air being discharged from the chamber.
In accordance with a second aspect of the invention, there is provided a heat-treating apparatus comprising: a chamber of airtight structure having a door; a plurality of discharge passages communicating with the chamber; a heat-exchange means in which is integrally incorporated an outside air introducing passage communicating with the chamber and containing a first control valve; a suction means connected to the plurality of discharge passages and having a second control valve, and a controller means for controlling the suction means and the first and second control valves.
The invention will now be further described, by way of example, with reference to the accompanying drawing, which is a sectional view of a preferred example of a heat-treating apparatus according to this invention.
Numeral 1 denotes an airtight chamber having a door 2. The airtight chamber 1 is shielded by two external walls, between which is preferably incorporated a heat insulating material. Numeral 3 denotes a discharge passage disposed along the outside or inside (not illustrated) of the chamber. The discharge passage 3 comprises a large number of conduits 4 disposed in parallel with each other.
Each conduit 4 is of a small calibre and is provided with a large number of heat-exchange fins 5. Numeral 6 denotes an outer air introducing passage formed concentrically in a tubular form along the outside of the discharge passage 3. Like the discharge passage 3, the outer air introducing passage 6 is provided with an opening 6a which communi cates with the chamber 1. The outer air introducing passage 6 is provided with a large number of stages or baffles 7 so that the outer air can be introduced in a zigzag form.
Thus, a heat-exchange means A is obtained.
Numeral 8 denotes an outer air introducing pipe which communicates with the outer air introducing passage 6. The outer air introducing pipe is provided with a control valve 9 which may be actuated automatically or manually. Numeral 10 denotes a discharge pipe which communicates with the discharge passages. The discharge pipe 10 is connected to a suction means 12, such as a suction motor, by way of a control valve 11 which may be actuated automatically or manually. Accordingly, the air within the chamber 1 may be suctioned to outlets 3b from inlets 3a of the discharge pipe 10 by actuating the suction means 12, and finally discharged into the outer air by way of the discharge pipe 10.
Consequently, the air pressure within the chamber 1 is reduced. The level of air pressure reduction may be controlled by regulating the suction force of the suction means 1 2 while considering the heat-treating degree of articles within the chamber. Generally speaking, the difference between the reduced air pressure within the chamber 1 and then normal air pressure thereoutside may be slight.
Numeral 1 3 is a drain pipe disposed at an end of the discharge pipe 10. In operation of the process, the vapourized water content within the chamber 1 is passed through the discharge passages 3 and discharged outside the chamber 1, the water content (extracted liquid) cooled and condensed by the heatexchange means A can be discharged outside the chamber 1 by actuating the valve 14.
Numeral 1 5 denotes an air intake pipe directly communicating with the chamber 1.
When cooling the interior of the chamber 1 rapidly, outer air may be introduced into the chamber by opening automatically or manually a valve 1 6 disposed in the air intake pipe 1 5. It is optional for there to be one or more such air intake pipes 1 5. Numeral 1 7 denotes a heat source, such as an infrared heater, an oil heater or the like, disposed in the chamber 1. Numeral 18 denotes a temperature detecting element and numeral 1 9 denotes a pressure detecting element, both of which are disposed in the chamber 1 and connected to a controller 20. The controller can be integrally formed or mounted with the chamber 1 or be separated therefrom.By operation of the controller 20, a difference between the air pressure in the chamber 1 and the external atmospheric pressure may be established. Numeral 21 denotes a humidity detecting element disposed in the chamber 1. Numeral 22 denotes an indicating/operating section having various measuring meters, timers, switches and programme meters. The suction means 12 and the control valves 9, 11 are also connected electrically to the controller 20.
The operation of the abovedescribed heattreating apparatus according to this invention will now be described.
First of all, a desired heating and drying programme is preset by the controller 20 and actuated. Subsequently, the heat source 1 7 and suction means 1 2 are actuated and the air pressure within the chamber 1 reaches a desired reduced level. Thus, air in the chamber 1 is forcibly removed by the suction means and discharged by way of the discharge passages 3 and the discharge pipe 10.
In the meantime, the air temperature in the chamber 1 is raised rapidly by the heat source 1 7.
The degree of air pressure reduction in the chamber 1 is selectably controllable by regulating the suction force of the suction means 1 2. When the pressure has been reduced to a suitably preset level, the suction means 1 2 is deactuated and the control valve 11 is closed, whereby the air pressure within the chamber is established at a preferred reduced level.
By providing the heat-treatment at a reduced air pressure within the chamber 1, the articles therewithin are heat-treated or dried effectively.
When the degree of air pressure reduction within the chamber 1 becomes less than a preset level, the suction means 1 2 is again actuated and the control valve 1 2 is opened, whereby the air pressure reducing operation is repeated.
By opening the control valve 9 of the pipe 8 which communicates with the outer air introducing passage 6, cooled outside air is introduced into the passage 6 via the pipe 8, and flows in a zigzag path along the large number of stages or baffles 7, passes between the large number of heat-exchange fins and is finally passed into the chamber 1 by way of the inlet 6a. In this case, the cool outside air is effectively heat-exchanged with the heated air passing through the discharge passages 3 by means of the heat-exchange means.
Thus, the heat energy within the chamber is not discharged wastefully outside the chamber but is used to heat incoming air, whereby to avoid the heated air in the chamber being cooled by incoming cold outside air.
The quantity of the air heated by the heatexchange process and introduced by the outer air introducing passage 6 is depressurized at a balanced level by suitably adjusting the opening degree of the control valve 9 and actuating the suction means 1 2 continuously. Accordingly, the vapourized water content of the chamber 1 can be discharged immediately.
Using the present technique, in the case that the operation of the suction means and the opening/closing operation of the control valve are carried out mutually and the outer air is introduced intermittently, the cold outer air is of course heat-exchanged effectively with the heated air within the chamber, and heated thereby. At the same time, in the case that the control valve is open, the suction means is actuated continuously and the air discharge and outer air introduction are carried out simultaneously while maintaining a reduced air pressure within the chamber at a balanced level, the aforesaid heat-exchange process may be conducted.
Accordingly, the air temperature of the chamber is prevented from being reduced by the cold outside air, in that heat energy within the chamber is employed effectively without any heat loss and the heat-treating (heating, drying or the like) time can be shortened considerably. As a result, the present invention may attain a large energy-saving effect.
According to another aspect of this invention, since the temperature drop in the chamber is prevented, the quality of the dried articles is excellent. Thus, articles placed within the chamber may be heat-treated in a high quality manner. From this point of view, this invention is very effective for expediting the growth of medical plants, marine plants, vegetables, fruit, flowers and other plants.

Claims (5)

1. A heat-treating process comprising: forcibly suctioning air from within an airtight chamber and maintaining the pressure differential between the air pressure within the chamber and the normal air pressure outside the chamber at a predetermined level; heating the air within the chamber to a predetermined temperature by a heat source disposed therewithin; discharging vapourized water from within the chamber; and heat-exchanging cold outside air introduced into the chamber from the outside thereof with thermal energy of heated air being discharged from the chamber.
2. A heat-treating process substantially as hereinbefore described with reference to the accompanying drawing.
3. A heat-treating apparatus comprising: a chamber of airtight structure having a door; a plurality of discharge passages communicating with the chamber; a heat-exchange means in which is integrally incorporated an outside air introducing passage communicating with the chamber and containing a first control valve; a suction means connected to the plurality of discharge passages and having a second control valve, and a controller means for controlling the suction means and the first and second control valves.
4. A heat-treating apparatus comprising an air-tight chamber for receiving articles to be heat treated, a suction means connected by a plurality of discharge passages to the interior of the chamber for selectively removing air from the chamber and thereby reducing the pressure therein relative to the outside atmospheric pressure, a heater in the chamber for heating the air therewithin, and one or more air intake passages for enabling outside air to be introduced into the chamber, the intake passages and discharge passages being interconnected in a heat-exchanging manner whereby the colder outside air is pre-heated before entering the chamber by means of the relatively hot air extracted from the chamber by the suction means.
5. A heat-treating apparatus constructed and adapted to operate substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.
GB08411479A 1984-05-04 1984-05-04 Heated chambers for growing plants Expired GB2158222B (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
GB08411479A GB2158222B (en) 1984-05-04 1984-05-04 Heated chambers for growing plants
DE19843416617 DE3416617A1 (en) 1984-05-04 1984-05-05 METHOD FOR HEAT TREATMENT AND DEVICE THEREFOR
FR8407564A FR2564575A1 (en) 1984-05-04 1984-05-16 METHOD AND DEVICE FOR THERMAL TREATMENT BY REDUCING REGULATING AIR PRESSURE IN A CHAMBER

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB08411479A GB2158222B (en) 1984-05-04 1984-05-04 Heated chambers for growing plants

Publications (3)

Publication Number Publication Date
GB8411479D0 GB8411479D0 (en) 1984-06-13
GB2158222A true GB2158222A (en) 1985-11-06
GB2158222B GB2158222B (en) 1987-11-18

Family

ID=10560501

Family Applications (1)

Application Number Title Priority Date Filing Date
GB08411479A Expired GB2158222B (en) 1984-05-04 1984-05-04 Heated chambers for growing plants

Country Status (3)

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DE (1) DE3416617A1 (en)
FR (1) FR2564575A1 (en)
GB (1) GB2158222B (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000040910A1 (en) * 1999-01-05 2000-07-13 Universal Preservation Technologies, Inc. Vacuum control system for foam drying apparatus
GB2560016A (en) * 2017-02-27 2018-08-29 Roche Sean Method and apparatus for obtaining usable water
WO2019143254A1 (en) * 2018-01-16 2019-07-25 Waister As Modular system and process of drying solids and liquid-solid mixtures

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB746433A (en) * 1953-04-09 1956-03-14 Hjorth & Co Ab Improvements in or relating to ventilation systems for shelters
GB1072092A (en) * 1963-05-20 1967-06-14 Exxon Research Engineering Co Atmospheric conditioning process and apparatus

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1553117A (en) * 1967-12-01 1969-01-10
US4169321A (en) * 1976-06-16 1979-10-02 Airtech Systems, Inc. Waste heat recycling system
DE2939902A1 (en) * 1979-10-02 1981-04-09 Jagri Maschinen- Und Apparatebau Gmbh, 4423 Gescher Yarn-drying plant with optimal energy utilisation - from use of heat exchanger and partial recirculation of exhaust gas
US4319408A (en) * 1980-07-10 1982-03-16 Nobuyoshi Kuboyama Heating process and its apparatus in reducing air pressure within a chamber at a balanced level
NO154934C (en) * 1981-02-19 1987-01-14 Nobuyoshi Kuboyama HEATING INSTALLATION FOR A GAS FORM MEDIUM, SPECIFICALLY DRYING SYSTEM.
JPS58224269A (en) * 1982-06-23 1983-12-26 Nobuyoshi Kuboyama Method of pressure reduced equilibrium heating and apparatus thereof

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB746433A (en) * 1953-04-09 1956-03-14 Hjorth & Co Ab Improvements in or relating to ventilation systems for shelters
GB1072092A (en) * 1963-05-20 1967-06-14 Exxon Research Engineering Co Atmospheric conditioning process and apparatus

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2000040910A1 (en) * 1999-01-05 2000-07-13 Universal Preservation Technologies, Inc. Vacuum control system for foam drying apparatus
GB2560016A (en) * 2017-02-27 2018-08-29 Roche Sean Method and apparatus for obtaining usable water
WO2019143254A1 (en) * 2018-01-16 2019-07-25 Waister As Modular system and process of drying solids and liquid-solid mixtures

Also Published As

Publication number Publication date
FR2564575A1 (en) 1985-11-22
GB2158222B (en) 1987-11-18
DE3416617A1 (en) 1985-11-07
GB8411479D0 (en) 1984-06-13

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PCNP Patent ceased through non-payment of renewal fee

Effective date: 19920504