JPS59173024A - Heat storing and heating method and apparatus of greenhouse by solar energy - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermal storage heating method and apparatus using solar heat, which is particularly suitable for heating greenhouse cultivation rooms such as agricultural greenhouses and mushroom cultivation rooms. A huge amount of petroleum is consumed in agricultural greenhouses, and as a measure to save energy, storage of solar heat underground has been put into practical use.

This involves burying a large number of vinyl chloride pipes underground, and circulating high-temperature air inside the greenhouse during the day using a blower to increase the humidity on the ground of the greenhouse, which has a large heat capacity.
The amount of heat stored in the greenhouse is extracted by circulating low-temperature air inside the greenhouse. However, with this heat storage method, the humidity inside the greenhouse becomes abnormally high at night due to condensed water inside the PVC pipes, causing condensation on plants such as tomatoes and Kirari, which can cause various diseases. Disadvantages include that the carbon dioxide concentration decreases during heat storage, and that it is hardly effective, especially in winter, in regions where the daytime temperature does not rise and there is not much difference between the temperature inside the greenhouse and the underground flow. there were. The present invention has been made in view of these circumstances, and the conventional method is to use solar heat to store heat in the underground, which has a large heat capacity, in other words, to store heat by sensible heat. On the other hand, the method of the present application uses a material that selectively absorbs moisture in the air to absorb moisture from the relatively high temperature air in the greenhouse at night and dry it appropriately, and also prevents water vapor in the moisture absorbent. The condensation heat released during condensation and the wetting heat generated when condensed water adheres to the moisture absorbent increase the air temperature and heat the greenhouse. It performs desorption and regeneration, and mainly uses latent heat, as opposed to the sensible heat used in geothermal systems. Naturally, in the method and apparatus of the present invention, sensible heat is stored in the moisture absorbent due to its heat capacity proportional to its specific heat, but the effect of this is approximately 1/6 to 1/10 of that of latent heat. , so the explanation will be omitted in the future description along with the wetting heat. Hereinafter, a detailed description will be given based on one embodiment of an apparatus for carrying out the present method.

The desiccant used in the present method is preferably a substance that can selectively absorb water (5) vapor in the air.
In this sense, synthetic materials used as molecular sieves are ideal, but on the other hand, since the purpose of the present method is to serve as an alternative to petroleum energy, expensive materials are not suitable. It is clear that it cannot be used as a hygroscopic agent in the present method and apparatus. The inventor of this application is
As a result of studying materials that have the ability to selectively absorb water and are also economical, we found natural zeolite, which has been subjected to a certain activation treatment.
It has been found that comatose soil is suitable as it satisfies these requirements, and among these, mordenite is most suitable. In addition to the above, silica gel, alumina gel, or porous materials impregnated with aqueous solutions of strongly hygroscopic substances such as calcium chloride, lithium chloride, and glycols can be used as moisture absorbing agents in the present method. Can be used. In the above,
Porous materials are those that serve as carriers for chemical substances, such as diatomaceous earth, pumice, and brick (6), and activation treatment refers to
In the range of 0, it means that the firing treatment is performed for at least 30 minutes or more, and by this treatment, the pores of the zeolite etc. are fired and the selective absorption ability of water is imparted. 150”
' Below 0, this effect can hardly be expected;
If it exceeds 000, tissue destruction occurs and absorption capacity is also lost. Sori force gel etc. is ], 50C'O ~ 25000
It is preferable to perform activation treatment at a certain point. These moisture absorbers are
Use crushed or molded pieces to an appropriate size,
Its size is determined in relation to the output of the blower, which will be described later. Only one type of moisture absorbent may be used, or
Of course, they may be used in appropriate combinations. Such a moisture absorbent 1 is filled into a heat storage chamber 2 consisting of an airtight container provided with an air inlet and outlet. The heat storage chamber 2 may be airtightly separated from the surrounding environment, and does not necessarily need to be buried underground. However, from the standpoint of effective use of the ground surface,
It is desirable to bury it underground or to cover the surrounding area with a heat insulating material or the like to prevent heat from being lost to the outside environment. In order to fully demonstrate the effects of the method and device of the present invention, at least the ceiling of the greenhouse 3, preferably the entire periphery, is made of a double structure by extending the transparent body 3C with a slight space between the outside and the outside. It is preferable to prevent air from the cultivation chamber 3b side, which contains a large amount of water vapor from the ground surface, plants, etc., from entering the heat collecting chamber 3a, which is a fraction of the heat collecting chamber 3a. When using this device to heat a cultivation room surrounded by heat insulating material, such as a mushroom cultivation room, the roof of the mushroom cultivation room should be made transparent and the attic used as a heat collection room, or the attic should be used as a heat collection room. The solar heat absorbed by the water heater is radiated by a radiator, etc., and as a result,
Air whose temperature has been increased may be used, and in this application, the term "heat collection chamber" includes cases where such secondary heated air is sent out. Intake pipes 4a and 4b are disposed and opened at the upper part of the heat collection chamber 3a and the upper part of the cultivation room 3b, respectively.

4b is connected to a blower pipe 6 via a flow path switching valve 5, and this blower pipe 6 is connected to a blower pipe 6 through a blower 7 to
It is connected to a perforated vibrator 2G that blows out the air buried inside. On the other hand, the exhaust pipe 8 that opens into the upper space in the heat storage chamber 2 branches into two branches via a flow path switching valve 9, one branch pipe 10a opens into the atmosphere, and the other branch pipe 10b, It opens into the cultivation chamber 3b. To outline the operating method of the device configured in this way, first,
Air in the heat collection chamber that has risen due to sunlight is sent into the heat storage chamber 1 by the blower 7. The temperature of the introduced air has increased due to solar heat, and the relative humidity has decreased significantly, which promotes acute evaporation of moisture from the moisture absorbent. The air in the heat collection room is supplied by the number of outside air ports installed at the bottom of the greenhouse (
It is replenished from (9) (not shown). The air that has passed through the heat storage chamber has lower humidity and higher humidity due to heat of evaporation, etc., so it is introduced into the cultivation room 3b only when necessary, and the thick branch pipe 1
It is released into the atmosphere from 0a. The hygroscopic agent whose hygroscopic ability has been regenerated in this manner can retain its hygroscopic ability for a considerable period of time by closing the on-off valves 11 and 12. Next, at night, when the temperature inside the greenhouse drops, the air inside the greenhouse contains a large amount of water vapor supplied from the soil, plants, etc.
When the relative humidity approaches 100%, condensation begins to form. By switching the flow path switching valve 5, such humid air is sent into the heat storage chamber from the intake pipe 4b.

Here, water vapor in the air is absorbed by the moisture absorbent and condensed, releasing heat of condensation. Therefore, leaving the heat storage chamber,
Since the air returning into the greenhouse from the flow path switching valve 9 and the branch pipe 10b is properly dried and the temperature has increased, a drop in temperature and condensation inside the cultivation room are prevented (10). The above-mentioned blower is usually operated in conjunction with a thermostand so that the blower operates within a set temperature range. Examples of the natural zeolite used as the adsorbent of the present application include borazite, borosodite, dianite,
Examples include soda zeolite, oxalisite, and morden zeolite. These activated natural zeolites have a selective adsorption ability for carbon dioxide gas, and this adsorption equilibrium mainly depends on temperature, so when exposed to high-temperature air during the day, Carbon dioxide gas is released into this, and at night it is adsorbed, so it also has the secondary effect of adjusting the carbon dioxide concentration within the cultivation room. As mentioned above, the present heating method is highly dependent on the hygroscopic capacity of the hygroscopic agent, in other words, on the relative concentration of air which releases moisture from the hygroscopic agent and regenerates it. As is well known, if the absolute humidity is constant, the relative humidity will drop by about half as the air temperature rises, so even on a midwinter day when the outside temperature surrounding the fPA room does not exceed zero, this When outside air is taken into the heat collection chamber, its temperature rises and its relative humidity decreases, and when this air is introduced into the heat storage chamber, moisture is desorbed and evaporated from the moisture absorbent. Therefore, in the method of the present invention, even on a midwinter day when the outside temperature during the day is around 12°C, and even in the firefly sky, the temperature in the heat collection room often rises to 10°C or more during the day. Therefore, this air regenerates the moisture absorbent, and at night it is possible to generate and utilize the corresponding heat of condensation. This point is significantly different from the geothermal method, which requires the greenhouse air temperature to be higher than the ground temperature (normally, it cannot be expected to be effective unless it is 10 to 15 degrees higher than the ground temperature). In addition to the above-mentioned features, the present invention has the ability to adjust carbon dioxide gas content and prevent condensation within the greenhouse compared to conventional geothermal systems, and the greenhouse also has the following features:
Generally, the location is changed about once every three years to prevent damage from continuous cropping, but while geothermal systems are not easy to move, in the case of the present invention, underground installation is an essential requirement. It is extremely easy to install and move, and the on-off valve 11
a.

By connecting several independent heat storage chambers 2a, 2b in parallel and isolated by 12a, 11b, 12b, etc., heat can be stored and conserved on days when conditions are good, and it can be used for days when conditions are bad. It can function as a preliminary heat storage chamber. Examples are listed below.

〔Example〕

Temperature glass installed in Nagano type (height 7m, width 9m,
A tent made of vinyl sheets is placed on the outer wall within a height of 5m.
The heating system is separated into a heat collection room and a cultivation room by installing it at a distance of 0.5 to 1.0 m from the roof surface, and the heating system is almost the same as that shown in Figure 1. The experiment was conducted from mid-February to the following February. The moisture absorbent is a fist-sized piece of mordenite that has been calcined at a temperature of around 200% for 1 hour.
000 (13) kg is filled into the heat storage chamber, and around the heat storage chamber there is a thickness of 10
am Styrofoam encapsulated and used outdoors. On the other hand, as a control area, ha! Two vibrators with a diameter of 10 cm were installed 60 cm underground in a greenhouse with the same shape, size, and structure.
It was buried over a distance of 10 m, and air was continuously blown at a rate of 60 cubic meters per minute.On the other hand, 20 cubic meters per minute was sent to the device of the present invention, and the heat storage air was continuously blown for about 7 hours. In addition, the heat dissipation air blowing time at night for both plants starts blowing (heat dissipation) when the temperature in the cultivation guide falls below 5 o'clock, and then
The blower operation was controlled by a thermostat so that the blowing of air stopped when the temperature rose to O. As a result, during the period, the temperature in the greenhouse dropped to 200℃ in the control area, but did not drop below 600℃ in the greenhouse equipped with the device of the present invention. The amount of heat stored and the amount of heat released by the method of the present application are equal to the water vapor-activated mold, J. shown in FIG. For example, when the temperature of the moisture absorbent is (14)8oO and the equilibrium moisture content is 14o10 (point A in Figure 3)
, the moisture absorbent is regenerated with air at 33°am and 25%, the temperature of the moisture absorbent is 27oO, the equilibrium moisture content is 1o, 5% (point a)
If regeneration is stopped at , then air at 5°C and humidity 100cyo is sent to extract the heat of condensation. , A-) B → 0 → D → A'. Therefore, the length of line segment AB is ``accumulated (radiated) sensible heat is transferred to line segment AB.
The distance between and the line segment Do corresponds to the accumulated (radiated) latent heat, and the amount of heat storage and heat radiated can be estimated from the specific heat and heat of vaporization (heat of condensation) per unit scaled on the upper and right sides of Figure 3. It's easy.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram showing an embodiment of the device of the present application. FIG. 2 is an explanatory diagram showing the main parts of the device of the present application. FIG. 3 is a water vapor-active mordenite adsorption equilibrium diagram. (15) 145- JP 59-173024 (6)

Claims (1)

[Claims] (]) Natural zeolite, colloid, silica gel, alumina gel, or porous materials activated by firing in a certain temperature range, and highly hygroscopic chemicals such as calcium chloride, lithium chloride, Filling a heat storage chamber consisting of an airtight container with an air inlet/outlet with one or more moisture absorbing agents impregnated with an aqueous solution of glycols, etc., and supplying air that has become high temperature and low humidity due to solar heat into the heat storage chamber. According to
This promotes the desorption of water from the hygroscopic agent, and when heating the greenhouse is necessary, such as at night, the air with a high relative temperature inside the greenhouse is circulated through the heat storage chamber, and water vapor is selectively added to the hygroscopic agent. A solar heat storage heating method for greenhouses, etc., characterized by extracting condensed heat when water condenses. (2) The regenerative heating method according to claim 1, wherein the activation treatment is baking at a temperature in the range of 15,080 to 500°C for at least 30 minutes. 0) As a moisture absorbent, 3 in the range of 150°C to 500°C
2. The thermal storage heating method according to claim 1, which uses natural mordenite that has been calcined and treated for 0 minutes or more. (4) Air suction pipes opening into the solar heat collection room and the cultivation room are connected to a blower pipe via a flow path switching valve, and the air pipe is activated into an airtight container via a blower. Hygroscopic agents made of treated natural zeolites, colloids, silica gel, alumina gel, or porous materials impregnated with aqueous solutions of strongly hygroscopic chemicals such as calcium chloride, lithium chloride, and glycols. The exhaust pipe, which is connected to a heat storage chamber filled with one or more of the following gases and blows air to the moisture absorbent, and which has one end open inside the heat storage chamber, branches into two via a Nagarayu switching valve, and one of the branch pipes is connected to the atmosphere. A heating system for a greenhouse using solar heat, with one opening in the middle and the other opening in the cultivation room. (5) The heating device according to claim 4, wherein the heat storage chamber is covered with a heat insulating material. (6) Moisture absorbent activation treatment at 15,000 to 5,000C
5. The heating device according to claim 4, wherein the firing treatment is performed for at least 30 minutes or more in the range of .