JPS6047520B2 - Total heat exchange ventilation system - Google Patents

Description

[Detailed description of the invention] The present invention relates to a novel air total heat exchange ventilation system.

More specifically, the present invention relates to a novel total heat exchange ventilation device that consumes less energy in operating power, is easy to handle, efficiently exchanges moisture in the air, and has a heat exchange function at the same time.

Conventionally, there are methods for removing moisture (moisture) from the air and converting it into liquid, such as cooling methods, absorption methods, adsorption methods, compression methods, and mixing methods in which dry air is mixed in. Each method has been developed into a device and put into practical use. It is provided.

Among these methods, the cooling method involves bringing moist air into contact with a liquid surface or solid wall surface whose temperature is lower than its dew point, and condensing the moisture.However, the liquid temperature manipulation is indirect, and cooling side fluid cooling operation must be carried out. Therefore, the liquid wetting efficiency of this method is not necessarily high considering the amount of energy consumed by the device. The absorption method is a method in which humid air is brought into contact with a hygroscopic solid or liquid to chemically or physically absorb and remove water vapor. When performing this operation, it is necessary to perform an absorbent regeneration operation in parallel. Therefore, the device becomes large and the method is not necessarily advantageous in terms of energy. The adsorption method is a method in which humid air is brought into contact with a solid adsorbent to adsorb and separate moisture. Depending on the selection of adsorbent, it is possible to obtain a considerable amount of liquid moisture even at room temperature, but the price of the adsorbent is high. In order to continuously obtain air with a constant humidity, it is necessary to regenerate the adsorbent, similar to the absorption method, and this method is not necessarily advantageous from an energy standpoint.

The compression method is based on the principle of compressing humid air while keeping it at a constant temperature to increase the total pressure and reduce the saturated humidity of the air, but it requires a cooling operation in parallel with the compression.

Therefore, the equipment cost and power cost are large, and it is suitable only when high-pressure, low-humidity gas is required, and it is difficult to say that it is a cost-effective method for general-purpose liquid humidification. Although the above-mentioned conventional methods certainly make it possible to achieve the required liquid humidity, moisture present in the air as a gas phase can be converted into water, that is, a liquid phase, or mixed with specific compounds or physically There are some that can be captured as targets or chemically adsorbed.

That is, it is a method that involves a phase change from a gas phase to a liquid phase or solid phase. Furthermore, most of these methods require the scavenger for moisture capture to be regenerated each time. Therefore, these methods have problems in terms of the operating energy and cost of the equipment (including the scavenger) and ease of operation due to their principle or operation. .

Accordingly, there has been a desire from various perspectives for an apparatus that is inexpensive and can efficiently remove moisture from the air. On the other hand, conventionally, as a method for ventilating the air within a system (for example, indoors), methods using, for example, a siphon jet, a ventilation fan, or a duct have been widely used.

The principle is simply that polluted air is expelled and replaced with clean air, powered by wind or an electric motor that rotates a fan. Although the above-mentioned conventional methods do provide the required ventilation, they do so without regard to the interaction of the heat provided by the ventilation air and the exhaust air.

Ventilation must be carried out in a wide range of areas, from ordinary homes to hospitals, hospitals, industrial areas, factories, transportation facilities, and places with special environments. To prevent oxygen deficiency, the ventilation volume and frequency are greater than expected. For example, houses and apartments are required to have at least 17 days/person-hour of ventilation, and entertainment venues are required to have 25 to 75 days/person-hour of ventilation, with a ventilation frequency of at least 6 times/hour. When such a large volume of air is required to be ventilated, and when heating and cooling is being carried out, conventional methods of ventilation can only cool or even warm the air! This air is then wasted and wasted during ventilation. In order to compensate for these drawbacks, a cross-flow type total heat exchange ventilation device is also known in which plate-like sheets of paper folded into many corrugated shapes are stacked alternately as a moisture-permeable membrane (in particular, Japanese Publication No. 47-19990 ), but since the material is paper, the carbon monoxide in the emitted air is
It can penetrate into the introduced fresh air and reduce the ventilation effect.Furthermore, from the viewpoint of strength, the thickness is limited to about 200μ at the most, which limits the improvement of moisture permeation rate. There is.

Total heat exchange is the exchange of sensible heat and latent heat,
Usually latent heat occupies the majority. Considering that latent heat exchange is achieved by the movement of moisture, it cannot be said that the above-mentioned limitation in improving the rate of moisture permeation is a major drawback. Furthermore, due to the wavy shape, the heat resistance and effective surface area per unit volume are not always sufficiently large, and dirt cannot be easily removed by washing with water. In an attempt to improve this drawback, Japanese Unexamined Patent Publication No. 4
No. 8-49058, No. 48-100745 and No. 49
-1755 Unagi Publications include, for example, an example in which the passages for two types of fluids have essentially quadrilateral shapes (No. 48-49058), and examples in which the passages for two types of fluids have essentially quadrilateral shapes, and examples in which the passages for two types of fluids have an essentially quadrilateral shape, and in which the passages for two types of fluids have a thickness of 0.5 mm and are formed of plastic films, porous ceramics, paper, nonwoven fabrics, etc. 100TIrft1 diameter 3T! r
! A kraft paper vibrator (No. 48-100745) or a post-treated version thereof (No. 49-17550) is described.

However, although such attempts certainly improve the cross-flow type total heat exchange ventilation system in some respects, the vibrators used therein are made of kraft paper or the like and shaped like triangles, squares, etc., as shown in those examples. It is made into a cylindrical shape, or treated with polyhydric alcohol or deliquescent inorganic salt, and is industrially significant in terms of the uniformity of the finished cylinder and the simplicity of the manufacturing process. This is inconvenient.

As a result of intensive research to improve the drawbacks of such conventional methods, the present inventors have found that by using hollow tubes of specific dimensions made of specific organic polymers, high performance and high product uniformity can be achieved. The present invention has been achieved by making it possible to create a total heat exchange ventilation device that has excellent flexibility with respect to operating conditions and has an extremely simple manufacturing process.

That is, the present invention provides a device for bringing two types of air having different temperatures and/or humidity into contact via a hollow tubular permeable membrane to exchange temperature and/or moisture, comprising (1) the hollow tubular moisture permeable membrane; The membrane is made of a material in which a hollow tubular membrane of regenerated cellulose that can be melt-spun is impregnated with polyhydric alcohol, and (Ii) the inner diameter d and the membrane thickness of the hollow moisture permeable membrane are respectively 0.5 to 5.
0T! Un and in the range of 10 to 250μ, and (1
11) A total heat exchange ventilation device characterized in that the ratio of the effective length L to the inner diameter d of the hollow tubular moisture permeable membrane is .

The hollow tubular moisture-permeable membrane in the present invention is regenerated cellulose made from lower alkyl ether of cellulose or acetate of cellulose, and particularly preferably one made of a material in which the regenerated cellulose is impregnated with a polyhydric alcohol, particularly glycerin. It is. Conventionally, various materials have been proposed as organic polymer films for the purpose of material exchange or as materials for hollow fibers.

For example, there are many polymers such as polyester polymers, polyamide polymers, polypropylene, polystyrene, etc. Among these, those with excellent moisture permeability are regenerated cellulose polymers and polyvinyl alcohol polymers.

However, polyvinyl alcohol-based materials are inferior in melt moldability, and regenerated cellulose-based materials are preferred. Among these, regenerated cellulose obtained from cellulose acetate is particularly preferred. The specifications of the hollow tube constituting the ventilation device of the present invention satisfy the following equations, where the tube inner diameter is d, the membrane thickness is t, and the effective length is L.

In a total heat exchange type ventilation system, the efficiency of energy recovery is determined by the total heat exchange amount (i.e., sensible heat exchange amount and latent heat exchange amount).
In addition, the cost of blowing power must be considered.

In order to increase the rate of exchange of sensible heat and latent heat (that is, moisture), the film thickness t should be as thin as possible. Also, in order to increase the contact area, it is better for the inner diameter d to be as small as possible;
It is easy to understand that the smaller the value of t, the smaller the film thickness t, which further increases the exchange efficiency. However, if the inner diameter d is small, the pressure loss of the blowing air becomes large, and the vibrator is contaminated by dust contained in the exhaust and intake air, and furthermore, it becomes blocked.

Furthermore, it is extremely difficult to clean it afterwards. Furthermore, if the inner diameter is made smaller, the total heat exchange efficiency increases, but the power required for blowing the air increases, so the overall energy recovery rate decreases.

On the other hand, if the inner diameter is increased, the blowing power will be reduced, but
The effective area is smaller than the volume, and furthermore, the wall thickness must be increased to maintain the mechanical strength of the vibrator.
This results in a decrease in heat and humidity exchange efficiency. One feature of the present invention is that the hollow tube of the present invention can be manufactured continuously, and this feature is achieved for the first time by the optimal combination of material, inner diameter, and film thickness. .

Further, in the present invention, there is a relationship between the inner diameter d of the hollow tube and the effective length L of the hollow tube as follows: 100≦L/d≦700.

The value of L/d has the most preferable value according to the expected operating conditions, that is, the average flow rate, and these values are "
(1) 2r! 1.1SeC≦■≦4rr1, Isec 35KL/d〈700(2)47T1. ISeC<
■If ≦6m1sec 250≦L/d≦500 (3)
6TL. When ISeC<n, the range is 200<L/d<400.

In addition, if d=10rrLIm. ．． L=1.0
m,. U=2TL. In ISeC, L/d=100
Even at 0, the overall heat exchange efficiency is 0.77, which is a sufficiently high value. However, under such conditions, the pressure loss due to the hollow tube tends to be large. From the above facts, L/d is particularly preferably 350 to 400.

This is important in creating a highly flexible device. That is, when a total heat exchanger having certain specific specifications is installed at a specific location, the desired amount of heat exchange will vary depending on the season, weather, etc.

In such a case, changing the equipment each time requires a great deal of cost and effort, so it is desirable to change the operating conditions to accommodate the changes if possible. By the way, in a total heat exchange device having a hollow tubular membrane, the overall energy efficiency is affected not only by the total heat exchange amount but also by the required power.
It is clear from the overall thermal efficiency column in Table 1 that if the operating conditions are changed unnecessarily, energy loss may occur in areas where the pressure drop is large. Therefore, it is desirable that the total heat exchange amount be such that the performance can be maintained at a high level even under such changes in operating conditions.

According to the present invention, it is possible to provide such an ideal total heat exchanger.

Examples are given below to further clarify the effects of the present invention.

In this example, θ is the ventilation air volume [DIHO, ΔHO is the enthalpy difference between the exhaust air and the introduced air [KCall7Tl
], ΔH1 is the total heat exchange amount [KcalIHR], ΔH2 is the blowing power heat value conversion value [Kcall(R)], φ is the total heat exchange rate [-], P is the blowing power [KW], ΔP is the blowing power inside the hollow tube Pressure loss between inlet and outlet [WnAg], U is average wind speed in hollow space [7TI.1sec], N is number of hollow tubes [-]
, t is hollow tube membrane thickness [m], L is hollow tube effective length [m], φ
T is the overall heat exchange efficiency [-] considering the blowing power,
The following relational expression holds between each constant and variable.

[However, ηT is the volumetric efficiency of the blower, ηT=0.6
Set to 0.

] [However, E is the coefficient of performance of the refrigerator, and E = 4.0.

] Example 1 28.5% by weight of polyethylene glycol (molecular weight 40
Cellulose acetate having a degree of polymerization of 180 and containing 0) as a plasticizer was dissolved in acetone to prepare a 2% by volume acetone solution of cellulose acetate, and a film was formed on a glass plate by the Kjästeinde method.

The membrane thus obtained was diluted with an aqueous solution of caustic soda (NaOH3
．． The mixture was saponified at 80° C. for 3 minutes in O2 weight %), washed with water, impregnated with glycerin, and dried to obtain a cellulose membrane with a thickness of 108 μm.

The moisture permeability of the membrane thus obtained was determined according to JISZO2O8-1.
It was measured by the cup method according to 953 regulations. For comparison, a commercially available cross-flow laminated total heat exchange fan (Mitsubishi Electric's "LOSSNAY 21V"
-1500) used in special synthetic paper (thickness 208
μ) was also measured in the same way.

The results are shown in Figure 1. The membrane of the present invention has excellent moisture permeability.

If it is formed into a hollow tubular shape, the film thickness can be made even thinner, which shows the superiority of the present invention. Example 2 A cellulose film (thickness: 100 μm) prepared in the same manner as in Example 1 was used to measure the permeation amount of carbon monoxide and carbon dioxide gas.

The measurement method is to use two glass cups (45 mt) each having branch pipes for intake/exhaust and sampling, sandwich the film between the openings of the cups, and apply vacuum grease to the contact area between the container and the film to prevent air leakage. After that, introduce indoor air into the lower side and seal it with a silicone rubber stopper, then quickly replace the inside of the upper container with 100% carbon dioxide gas or 100% carbon monocarbide. 0.5m1
Samples were taken, and the VOl% of carbon dioxide gas or carbon monoxide was measured using gas chromatography. For comparison, a similar test was conducted on the same special synthetic paper used in Example 1.

However, sampling was performed after 2 minutes. In both cases, the gas permeation area was approximately 6 cr1.

The results are shown in the table below. From the table above, compared to the special synthetic paper, the paper of the present invention is significantly superior in its gas barrier properties against carbon dioxide and carbon monoxide, which must be discharged through ventilation.

Example 3 From cellulose acetate chips with a degree of polymerization of 180 containing 28.5% by weight of polyethylene glycol (molecular weight 400) as a plasticizer,
A hollow vibrator was manufactured using the method disclosed in Publication No. 2, saponified in a 3% by weight aqueous solution of caustic soda at 80°C for 3 minutes, washed with water, and dissolved in a 4% by weight aqueous glycerin solution.
By passing it for a minute and impregnating it with glycerin, the film thickness is 75μ and the average inner diameter is 0.5mm. , 1.0Tn1TL and 1.5? Three types of regenerated cellulose hollow tubular membranes were prepared.

Using an acrylic tube with an inner diameter of 100Tr0fL, if the inner diameter of the hollow tube is 0.5, 12,000 pieces, if the inner diameter is 1.0WL, 3000 pieces, and the inner diameter is 1.5T0! 1300 for L
Fill them uniformly so that the hollow tube bundle occupies approximately 30% of the cross section of the acrylic cylinder, and fill the tubes with effective lengths of 0.25rr1, 0.5m1 and 1.0m, respectively.
A module was created.

The ends of the hollow tubes were sealed with urethane resin. Examples of the structure of the prototype module are shown in FIGS. 2 and 3. Room temperature 26℃
In the center of room A, which has a floor area of 60 i and a volume of 180 d, the temperature and humidity are adjusted to a relative humidity of 55%, the room is surrounded by an insulated wall, and the temperature is 30 d.
℃, relative humidity controlled at 80℃ internal volume approx. 2
A constant temperature and humidity chamber B of 0 d was provided, and heat and humidity exchange between air A and air B was performed using the above module.

Temperature was measured with a thermocouple, humidity was measured with an Earthman ventilation hygrometer for each room A and B, and an AY-2 type sensitive hygrometer (Ace) for each air discharged from the module.
(manufactured by Scientific Corporation). The flow rate of each air was controlled by a valve so that the flow rate was the same, and was measured by a rotameter.

Measure the pressure drop between the inlet and outlet of the hollow tubular membrane. The theoretical power required for air blowing was calculated based on the flow resistance of the empty tubular membrane.

The results are shown in Tables 1 to 3.

Example 4 Same as Example 3, average inner diameter 5T0n, film thickness 220
A hollow tubular membrane of μ was prepared, and 120 membranes were similarly filled into an acrylic cylinder with an inner diameter of 100 mm, and the effective length was 0.5 Tn. , 1m
and 27n modules were created.

A performance test of the module was conducted in the same manner as in Example 3.

The results are shown in Table 4. As explained in detail above, the device of the present invention can be used for swinging, which consumes less power and energy.
The device also has extremely excellent features such as being smaller in size than conventional humidity control devices when comparing the same efficiency, generating extremely little noise, being easy to operate, and being highly safe.

Therefore, it is natural that the device can be used in many fields where conventional devices are used, and by taking advantage of these characteristics, it can be used advantageously in various fields. For example, it is useful as a dehumidified air supply device for small household use, hospitals, schools, buildings, transportation facilities, experiments, industry, and even equipment that uses compressed air. In addition, since the total heat exchange ventilation device of the present invention has an efficient ventilation function in addition to the above-mentioned total heat exchange function, it can be used in fields where conventional ventilation devices are used, and in other fields as well. The features of this device are that it can supply clean air with no or a small temperature difference from the air A to be ventilated, that is, that ventilation without heat shock is possible, and that the materials that make up the device are Because it is a polymeric material, it is light in weight, has excellent chemical and heat resistance, and dirt can be removed by washing, and the need for repair is very low. Furthermore, it is useful as a ventilation device for hospitals, schools, buildings, transportation facilities, experiments, and industrial use.

[Brief explanation of drawings]

FIG. 1 is a graph showing the results of Example 1. FIGS. 2 and 3 are a schematic diagram and a sectional view of the experimental apparatus used in Examples 2, 3, and 4. 1, 2, 3, and 4 are air inlets and outlets, 5 is 1 oil, 6 is a hollow tubular moisture permeable membrane, and 7 is a container.

Claims (1)

[Claims] 1 A device that allows two types of air with different temperatures and/or humidity to come into contact via a hollow tubular moisture-permeable membrane to exchange temperature and/or moisture, wherein (i) the hollow tubular moisture-permeable membrane is capable of melt spinning. (ii) the inner diameter d and thickness of the hollow tubular moisture-permeable membrane are in the range of 0.5 to 5.0 mm and 10 to 250 μ, respectively; and (iii) the ratio of the effective length L to the inner diameter d of the hollow tubular moisture permeable membrane is L/d=100 to 7.
A total heat exchange ventilation device characterized in that: 00.