JPS5880463A - Absorption type air-cooling system - 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 an absorption cooling system that utilizes the effect of an adsorbent such as zeolite absorbing a refrigerant such as water or ammonia, and an object of the present invention is to operate the cooling cycle efficiently.

In recent years, the absorption cooling cycle has been reconsidered as the simplest and most efficient method.
Many refrigeration and air conditioning systems are used that utilize the absorption of water vapor by solids or liquids and release at high temperatures, as well as those that utilize the dissolution of water vapor in lithium bromide.

However, common adsorbents containing silica gel
As shown in the figure, the amount of adsorption at low temperatures is proportional to the partial pressure of water vapor, but at high temperatures it is almost constant with respect to changes in the partial pressure of water vapor. Therefore, the difference between the amount of adsorption at low temperature and low partial pressure and the amount of adsorption at high temperature and high partial pressure is small, and this is the reason why the cooling efficiency of conventional refrigeration systems using silica gel adsorbents is low. Although absorption cooling systems that utilize solar heat have been gaining popularity in recent years, they have had the problem of extremely low efficiency under adverse conditions such as low radiant temperature due to heat from the sun and high condensation temperature due to air-cooled condensers. .

Therefore, in order to eliminate these drawbacks, zeolite etc.
As shown in the figure, adsorbents that use adsorbents whose adsorption crosstalk exhibits a nearly constant amount of water adsorption with respect to changes in water vapor pressure are attracting attention.

For example, what is shown in Japanese Patent Publication No. 53-129333 is as shown in FIG.
5 is based on solar heat utilization, and 31・-1 As shown in Figure 2, there is a storage body 16 filled with an adsorbent such as zeolite, and a condenser that condenses refrigerant such as water vapor desorbed and released by solar heat. 17, an evaporator 19 having an expansion valve 18 for expanding the condensed refrigerant, and a confinement space 2o, each of which is designed to prevent the refrigerant from flowing backwards. It is connected by a line equipped with a check valve (21°22.231) at an appropriate location.

To explain the operating mechanism for obtaining the cooling effect, the storage body 1
When 6 absorbs solar heat, the refrigerant such as water vapor adsorbed to the adsorbent such as zeolite filled inside is desorbed.

At this time, the pressure increases as the temperature inside the storage body 16 rises, and when the pressure rises to a certain value, the check valve 21 opens, and the desorbed refrigerant is introduced into the condenser 17. Ru.

Here, the refrigerant is condensed by an air cooling fan 24 or water cooling, and the liquid refrigerant expands through an expansion valve 18 installed near the inlet of the evaporator 19 and becomes gaseous, thereby cooling the evaporator 19. . The evaporated gaseous refrigerant passes through the check valve 22 and enters the confined space 2o. At night, when the storage body 16 is cooled and the partial pressure decreases, the check valve 23 opens and the refrigerant enters the storage body 16. This series of cooling cycles is used for air conditioning or refrigeration.

However, in the absorption cooling system configured in this way, the refrigerant desorbed from the storage body 16 is condensed in the condenser 1 and is directly evaporated in the evaporator 19, so the balance between the amount of condensation and the amount of evaporation must be adjusted. is very difficult. That is, when the amount of refrigerant desorbed from the storage body 16 is small, such as on a cloudy day, the temperature of the refrigerant passing through the condenser 17 decreases, and the partial pressure in the conduit from the condenser 17 to the expansion valve 18 decreases. This has the disadvantage that the difference in partial pressure within the evaporator 19 located behind the expansion valve 18 becomes small, and the effect of expanding the refrigerant in the expansion valve 18 is reduced. However, in a method in which the refrigerant is desorbed by forcibly heating the storage body 16 using heating such as gas heating, the temperature of the refrigerant desorbed from the adsorbent is high and the amount of desorption increases. For this reason, it may be necessary to increase the condensing capacity by increasing the size of the condenser 17, or it may be necessary to increase the condensing capacity by making the condenser 17 larger.
In order to evaporate the refrigerant with relatively high humidity and temperature, the evaporator 19
However, this method had the drawback that it required some effort to increase the evaporation capacity of the evaporation capacity, which led to an increase in costs due to the larger size of the equipment.

The present invention eliminates the above-mentioned conventional drawbacks, increases the operating efficiency of a cooling system, and provides a smooth operating cycle. An embodiment of the present invention will be described below as a fourth embodiment.
This will be explained based on the diagram.

1 indicates the entire cooling system, 2 indicates zeolite, water, etc.
A storage tank with a built-in adsorbent whose crosstalk such as adsorption of refrigerants such as fluorocarbon gas is less dependent on pressure and more dependent on temperature; 3 is a condenser that condenses the refrigerant; 4 is a condensed refrigerant that has become liquid. A storage refrigerant tank 5 is an evaporator that evaporates refrigerant, and is a main element of the cooling system 1. The refrigerant tank 4 is installed above the evaporator 6, and each element is connected with piping using steel pipes or the like.

In addition, on the inlet side of the condenser 3, there is a refrigerant condensation amount adjusting valve 6.
A refrigerant evaporation amount adjusting valve 7 is interposed on the outlet side of the refrigerant tank 4. 8 is a refrigerant adsorption adjustment valve 8 provided on the inlet side of the storage tank 2;
The pressure inside this pipe near 1 has been reduced by evacuation or the like.

Next, the operating status of this cooling system 1 will be explained.

First, the condensation amount adjustment valve 6 is opened, the evaporation amount adjustment valve 7 and the adsorption amount adjustment valve 8 are closed, and the storage tank 2 is opened.
ignite the gas cooking device 9 provided to heat the
Alternatively, as shown in the figure, heating can be done using solar heat.

As a result, the adsorbent inside the storage tank 2 that has already adsorbed the refrigerant is heated and the refrigerant is desorbed again. Next, this refrigerant passes through the condenser 3 and becomes condensed liquid refrigerant, which is stored in the refrigerant tank 4. When a predetermined amount of liquid refrigerant has accumulated, the condensation amount adjustment valve 6 is closed and the gas cooking device 9 is turned off.
Although not shown in the figure, a conventional cooling device such as air cooling or water cooling provided in the storage tank 2 is operated to cool the adsorbent contained in the storage tank 2. Next, the adsorption amount adjustment valve 8 is opened, and the evaporation amount adjustment valve 7 is adjusted according to the capacity of the evaporator 5 to transport the refrigerant to the evaporator 5. The evaporator 5 is usually installed in the indoor unit 7) of the air conditioner.
,,-7, and is discharged into the room as cold air by a blower fan 10 or the like.

The following is the basic operation of the cooling system of the present invention. For example, if we consider the case where water is used as the refrigerant and 100 zeolite is built into the storage tank 2, as shown in Fig. 2, the temperature is 26℃, rsvanH
Zeolite adsorbs 269 water at y, 20011:
Assuming that the zeolite was heated to 200 trm Hf at 10°C, the amount MD of moisture desorbed from the 10oKP zeolite is calculated by the following formula.

That is, approximately 201j of water is desorbed, condensed by the condenser 3, and stored in the refrigerant tank 4.

Now, 20 ml of moromi is ideally 1 oo without heat loss in each part.
If we consider the case of evaporation in a % evaporator, water′

Since the latent heat of vaporization of is 580 Kcan, 20X580=
This means that it has a cooling capacity of 11,600Kca12.

Generally, 1 horsepower air conditioner is 1800KcaI! ,/hr
However, in reality, the amount of zeolite to be filled is determined according to the purpose by calculating the adsorption efficiency of zeolite and heat loss in each part, and the amount of zeolite to be filled is determined based on the structure and materials to minimize heat loss. Needless to say, consideration must be given to reduce the amount of damage.

Therefore, the absorption cooling system of the above embodiment has the following effects.

A refrigerant tank 4 is interposed between the condenser 3 and the evaporator 5, and the refrigerant condensed in the condenser 3 is temporarily stored in the refrigerant tank 4, and the refrigerant according to the required amount is supplied to the evaporation amount adjusting pulp. It can be retrieved via. Therefore, there is no need to make complicated balance adjustments between the amount of condensation and the amount of evaporation of the refrigerant, and the sizes, capacities, etc. of the condenser, refrigerant tank, and evaporator can be selected relatively easily and independently.

By providing the refrigerant tank 4, it is possible to
For example, it is possible to store the refrigerant necessary for -day), and there is no need to set and operate the adsorption/desorption operation mechanism at the same time.

C. The temperature of the refrigerant stored in the refrigerant tank 4 decreases due to heat radiation, etc., and the partial pressure in the piping from the refrigerant tank 4 to the evaporator 5 junction + PT, l and the internal pressure in the piping from the evaporator 6 to the storage tank 2. Partial pressure IP, 2] is approximately equal to 1"T-e=P
Even if it becomes e-z', since the refrigerant tank 4 is located above the evaporator 5, the refrigerant can be sent to the evaporator 6 using the weight of the refrigerant without using the partial pressure difference. , the refrigerant evaporates easily.

That is, the position of the lowest end of the refrigerant tank 4 is hl from the floor surface.
, assuming that the top end of the evaporator is at a height of h2 from the floor surface, hl>h2, and the potential energy when a certain minute amount of refrigerant mq is at each point mentioned above is mghl.
, mgh2.

Now, when the evaporation amount adjusting pulp 7 is opened, the difference mg (hl - h2) in the potential energy between the two is converted into the kinetic energy of a very small amount mq of refrigerant, as if the above PT-e
(!: ``It works as if there is a pressure difference between e and z, and the refrigerant evaporates smoothly in the evaporator 5.

As is clear from the above description, the absorption cooling system of the present invention includes a storage tank containing an adsorbent such as zeolite, a refrigerant tank that condenses and stores the refrigerant desorbed by heating the adsorbent, and a refrigerant tank that stores the refrigerant after condensing it. The refrigerant tank is located above the evaporator, and the refrigerant condensed by the condenser is stored in the refrigerant tank, and then the refrigerant according to the required amount is pumped into a controlled pulp, etc. Since the refrigerant can be transported to the evaporator through adjustment, there is no need to balance the condensed and evaporated amounts of the refrigerant with a complicated mechanism, unlike when there is no refrigerant tank. The size, capacity, etc. of each can be selected relatively easily and independently.

Also, by appropriately considering the storage capacity of the refrigerant, it is possible to store the refrigerant required for a certain period of time (for example, - days), so there is no need to set up a mechanism that can perform adsorption and desorption operations at the same time. , economical.

Furthermore, since the refrigerant tank is located above the evaporator, the temperature of the refrigerant stored in the refrigerant tank decreases, and the pressure in the piping from the refrigerant tank to the evaporator increases. Even if the partial pressure in the pipe leading to the storage tank is approximately the same value, the refrigerant can be easily evaporated in the evaporator, and smooth cooling operation is possible.

[Brief explanation of the drawing]

Figure 1 is an adsorption isothermal diagram of silica gel used in a conventional absorption cooling system, Figure 2 is an adsorption isotherm diagram of zeolite that can be used in the absorption cooling system of the present invention, and Figure 3 is a conventional absorption isotherm diagram. System diagram of an absorption cooling system showing an example, Part 4
The figure is a system diagram of an absorption cooling system showing one embodiment of the present invention. 2...Storage tank, 3...Condenser%4
... Refrigerant tank, 6 ... Evaporator 0 Name of agent Patent attorney Toshio Nakao and 1 other person 1st
Figure 2 7° oride each: *lr: #ty'ThX) - Atmospheric pressure 3
4 Cypress and moxibustion employment Figure 3 Figure 4

Claims (1)

[Claims] A storage tank containing a built-in adsorbent such as zeolite, a condenser that condenses refrigerant such as fluorocarbon gas and water vapor desorbed by heating this adsorbent, a refrigerant tank that stores the condensed refrigerant, and evaporates the refrigerant. An absorption cooling system comprising: an evaporator for evaporation; the refrigerant tank is installed above the evaporator.