JP2000310433A - Ice storage air conditioning system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air conditioning system utilizing a low temperature heat source in the ice storage utilizing mid night power or the like as heat source for air conditioning and also achieve a miniaturization of an ice storage tank based on a high temperature difference, an elimination of drain piping and a higher heat efficiency. SOLUTION: This system is constituted of a heat pump 2 having a refrigerating capacity, an ice heat accumulation tank, outside air treating air conditioning equipment 3, a fan coil unit 4, piping and a duct for connecting the components and a pump fan for circulating a heat medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ice storage air conditioning system. It is more advantageous to use a lower blow air conditioning system for air conditioning, that is, a stratified air conditioning system.

[0002]

2. Description of the Related Art Various heat source devices have been used as heat sources for air conditioning. The combination of an electric refrigerator and a boiler is followed by a cold / hot water generator using gas fuel, an air heat source heat pump, etc.

[0003] Usually, these heat source devices generate the temperature required by the air conditioner and directly use the temperature. However, heat is stored for the purpose of reducing the installation capacity of the heat source device and operating the heat source device with high efficiency. It became so.

[0004] There are various systems for this heat storage, but the heat storage system mainly uses water. In recent years, an ice heat storage method that uses the latent heat of melting of ice by making this water ice has come to be used.

[0005] A comparison of the heat storage capacity of the heat storage tank between the water heat storage method and the ice heat storage method generally shows that when used in cooling, the upper limit of the use temperature is 15 ° C or less, and in the case of water heat storage, it is 8K.
It is about cal / kg. On the other hand, in the case of ice heat storage, the latent heat of melting of ice at 0 ° C is 80 Kcal / kg and sensible heat up to 15 ° C is added, so 95K
cal / kg, and the tank volume ratio is about 1:12. In the case of ice heat storage, it is necessary to consider the ice filling rate, so this varies depending on the filling rate. However, even if the ice filling rate is 40%, the tank volume becomes about 1/6 of that of water heat storage.

Regarding the stratified air conditioning system, the present inventor has already described the "low air blowing and upper suction air conditioning method" (Japanese Patent Application Laid-Open No. Hei 6-272890), the "lower air blowing air conditioning system by introducing fresh air" (Japanese Patent Application Laid-Open No. 7-225034), Mixed type lower blow air conditioner having dehumidifying function "(JP-A-7-225034),
An application has been filed as "Improvement of lower air conditioner and design and operation method of air conditioner" (Japanese Patent Application Laid-Open No. 9-14689).

The characteristics of a stratified air conditioner, that is, a lower blow air conditioner and an upper air blow air conditioner, exert their power in comfort and energy saving.

[0008]

The use of heat in ice heat storage is the same as in the case of using directly from a conventional refrigerator or in the case of using water heat storage, and particularly, the low temperature of 0 ° C. is not utilized. In other words, it is a waste of energy.

[0009] The volume of the heat storage tank is reduced by using the latent heat of melting of ice.
It is the same as when using water heat storage in ° C. If it can be used up to a high temperature exceeding 15 ° C, the volume can be further reduced.

[0010]

SUMMARY OF THE INVENTION According to the present invention, an air conditioner in an air conditioner is taken in for ventilation, the outside air is not mixed with the return air from the room, but is exclusively processed by an outside air processing air conditioner, and introduced directly into the room. An air-conditioning system that processes humidity and a temperature that cannot be processed by an air conditioner (usually a fan coil unit: FCU) dedicated to temperature processing is combined with an ice heat storage system.

A combination of an outside air processing air conditioner and a temperature processing air conditioner has already been filed for a patent application entitled "Improvement of Lower Blow Air Conditioner and Air Conditioning Design / Operating Method" (JP-A-9-14)
689), which is more advantageous when used.

[0012]

[Action] In the ice storage air conditioning system, antifreeze cooled by a refrigerator capable of producing ice is sent to an ice storage tank to store ice heat, and the antifreeze from the ice storage tank is sent to an outside air processing air conditioner (outside air conditioner) to remove outside air. It cools and dehumidifies and sends it to a fan coil unit (FCU) installed indoors to adjust the room temperature. (In heating, a refrigerator becomes a boiler, cooling becomes heating, and dehumidification becomes humidification.)

In the external air conditioner of the ice thermal storage air conditioning system, the air which has been cooled and dehumidified is supplied directly to the room using the air supply duct during cooling. Although the FCU processes temperatures that cannot be processed, the drain piping of the FCU can be omitted because there is no need for dehumidification.

The air conditioner using the lower blow air conditioner is also called a stratified air conditioner because the temperature distribution in the room is improved. The air that has been cooled and dehumidified at the time of cooling by an external controller is supplied to the outside air dedicated flow path of the lower blow-out FCU in the room using the air supply duct, and is supplied from the lower blow-out port together with the FCU operation. Of course, the drain piping can be omitted.

[0015] For cooling and dehumidification of the external air conditioner, the lower the heat source, the more advantageous the effect and the size of the heat exchanger of the air conditioner can be reduced.

Since the lower blowout FCU is a blowout in the living area, the blown air directly hits the resident. Therefore, the blowing temperature must be higher than that of the conventional method so as not to be uncomfortable because the blowing temperature is too low. A high temperature may be used as a heat source. Rather, if a low temperature is supplied, inconveniences such as dew condensation and further dehumidification or unpleasantness occur.

[0017] Therefore, the external controller uses the low temperature of the ice heat storage to further increase the temperature of the heat medium and blow it out to the lower chamber FC
By using it as a U heat source, effective use of energy and miniaturization of the heat storage tank are achieved.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiment will be described with reference to the most advantageous lower blow air conditioning system, that is, a stratified air conditioner system. FIG. 1 shows a stratified air conditioner system utilizing ice heat storage. 1 is an ice storage tank,
2 is an air heat source heat pump, 3 is an outside air processing air conditioner (outside air conditioner), 4 is a lower blow fan coil unit (FC)
U) and 5 are antifreeze-water heat exchangers (secondary heat exchangers).

These devices are appropriately connected by pipes and ducts. Each pipe is provided with a pump for circulating a heat medium. Reference numeral 6 denotes a heat source pump, 7 denotes a pump for an external conditioner, and 8 denotes a pump for FCU (secondary pump).

Each pipe is provided with a control valve. 9 is a three-way valve for controlling the heat source supplied to the external controller, and 10 is a three-way valve for controlling the temperature of the heat medium supplied to the FCU. Reference numeral 11 denotes a two-way valve for controlling the room temperature.

Each control valve is operated by a signal from a thermostat or a humidystat to control the heat medium. 12
Is a thermostat for detecting the temperature of supply outside air attached to the duct for supplying outside air, 13 is a thermostat for detecting the temperature of the heat medium supplied to the FCU, 14 is a thermostat for detecting room temperature, and 15 is a humidystat for detecting indoor humidity. .

The ice heat storage tank 1 has a heat exchanger 16 for generating ice therein, and water serving as ice is stored in the tank. Heat exchanger
16 has an air heat source heat pump 2 and an air conditioner 3,
There is an antifreeze circulating in the secondary heat exchanger 5. Brine is generally used as the antifreeze.

The air heat source heat pump 2 includes a compressor 17, a condenser 18, an evaporator 19, a refrigerant switching four-way valve 20, a throttle device (expansion valve) 21, a refrigerant pipe connecting them, and auxiliary machines. Of course, the air heat source heat pump 2 used here
Has the ability to produce ice. The illustrated arrows indicate the circulation of the refrigerant during ice formation.

The external air conditioner 3 comprises necessary equipment (omitted) such as an air brine heat exchanger (air conditioning coil) 22, an external air intake 23, an air supply fan 24, and other filters.

FCU4 is an air-cold water heat exchanger (coil)
It comprises necessary equipment (omitted), such as 25, outlet 26, inlet 27, and other fans, and is installed on the floor 28. Further, the FCU has a structure in which the outside air supplied from the outside air supply duct 29 from the outside conditioner and the room air are mixed and supplied to the room through the outlet 26 through the dedicated flow path.

The secondary heat exchanger 5 exchanges heat with water as a heat medium circulating between the brine whose temperature has increased after passing through the external conditioner 3 and the FCU 4. Water as a heat medium is supplied by an FCU pump (2
Next pump) 8 circulates

The ice heat storage operation will be described. The air heat source heat pump 2 and the heat source pump 6 are both operated.

When the air heat source heat pump 2 is in operation, the refrigerant is circulated by the compressor 17 in the direction of the arrow. The heat is radiated by the condenser 18 to liquefy. The pressure is reduced and cooled by the expansion valve 21. The evaporator 19 exchanges heat with the brine to evaporate and return to the compressor 17 again. This circulation is repeated.

The brine cooled by the evaporator 19 of the air heat source heat pump 2 enters the ice generating heat exchanger 16 inside the ice heat storage tank 1 by the heat source pump 6 and exchanges heat with water in the tank to remove ice. Generate. The direction of the brine flow is the direction of arrow 30. Generally, brine temperature is -3 ° C to -10 ° C
Degree is used.

The air-conditioning operation will be described. At this time, the ice is melted and released in the ice storage tank. In FIG. 1, the devices other than the air heat source heat pump 2 and the heat source pump 6 are both in operation.

The heat source side, that is, brine and water are circulated by the external conditioner pump 7 and the FCU pump (secondary pump) 8. At this time, a heat exchanger for ice formation inside the ice heat storage tank 1
The 16 brines flow in the direction of arrow 31.

The brine discharged from the ice storage tank 1 exchanges heat with the external conditioner 3 and further circulates through the secondary heat exchanger 5 to the ice generating heat exchanger 16 inside the ice storage tank 1.

The temperature of the brine heat-exchanged by the external conditioner 3 rises to about 13 ° C. at the external conditioner pump 7 and further rises to about 18 ° C. at the outlet of the secondary heat exchanger 5.

In the circulation on the side of the FCU 4, that is, in the water circulation by the secondary pump 8, since a relatively high temperature is favorable in view of the blowing temperature of the FCU 4, the heat source water is controlled and supplied to 15 ° C. to 17 ° C. This temperature setting is performed by operating the three-way valve 10 according to a signal from the thermostat 13 for detecting the temperature of the heat medium. The heat is exchanged by the FCU 4 to circulate to 20 ° C to 22 ° C.

In FIG. 2, the secondary heat exchanger 5 is omitted and FC
A bleed-in system in which water is circulated on the U4 side, that is, water circulation by the secondary pump 8, is directly connected to a pipeline of a brine system. In comparison with the method using the secondary heat exchanger 5, the brine temperature reaching the ice generating heat exchanger 16 inside the ice heat storage tank 1 is 20 ° C., which is the temperature after heat exchange in the FCU 4.
Since the temperature is 22 ° C., it is excellent in terms of effective use of the ice thermal storage tank 1. However, caution is required because the brine reaches the coil 25 of the FCU 4.

The outlet air temperature of the external conditioner 3 is set at about 16 to 17 ° C. in consideration of the indoor humidity. This is controlled by a supply outside air temperature detection thermostat 12. The indoor humidity is monitored by the humidy stat 15, and when the humidity increases, the outlet temperature is lowered to enhance dehumidification.
The supplied outside air is mixed with the room air in the room FCU 4 and blown out at a temperature approaching room temperature.

In the FCU 4, the heat source water is controlled by the two-way valve 11 in accordance with the signal from the room temperature detecting thermostat 14, and the room temperature is maintained.

The FCU 4 draws room air from the upper suction port 27 and exchanges heat with the suction coil 25 to blow it out from the lower outlet port 26. By blowing out slowly along the floor 28, a uniform temperature distribution is realized in a plane and a comfortable environment is realized.

Although the cooling operation has been described, the heating operation can be easily realized in the heating operation by switching the four-way valve of the heat source heat pump so that the illustrated condenser 18 functions as an evaporator and the evaporator 19 functions as a condenser. However, the ice heat storage tank 1 becomes a hot water heat storage tank and uses only sensible heat. The heat storage capacity decreases.

[0040]

The ice storage air conditioning system of the present invention is an air conditioning system that uses a heating medium, which separates the introduction of outside air for ventilation essential for a modern building forming a closed space and the temperature control of the room, for each temperature stage. It has a synergistic effect by combining the characteristics of ice heat storage, which can significantly reduce the size of the heat storage tank using latent heat of melting.

In the conventional air conditioning, a cold source having a cold water temperature of about 5 to 7 ° C. is required for dehumidification by cooling. If only the temperature is to be lowered, a temperature of about the well water (around 15 ° C) is sufficient. In refrigerators and heat pumps, the higher the evaporating temperature, the higher the coefficient of performance and energy saving. The use of ice heat storage solely for heat storage exerts an effect by effectively utilizing the low energy of ice, which is disadvantageous in energy compared with the conventional method.

When the features of the ice storage air conditioning system are summarized, the following effects can be expected. 1) Since the low temperature taken out of ice is used for the outside air treatment for ventilation, it is effective for cooling and dehumidification, particularly for dehumidification. 2) The heat source whose temperature has increased due to the outside air treatment can be used for temperature control of the FCU system that controls room temperature. 3) The heat source has a high temperature difference due to the stepwise use, and the heat storage tank can be further reduced in size. 4) In an FCU system having a relatively high temperature, heat loss from piping is reduced, so that heat insulation can be simplified. 5) The drain pipe of the FCU can be omitted. 6) It is possible to prevent a freezing accident of a heat exchanger (secondary heat exchanger) that produces heat source water of an FCU system that exchanges heat with a heat source whose temperature has increased due to outside air treatment.

[Brief description of the drawings]

FIG. 1 is a diagram of an ice thermal storage air conditioning system.

FIG. 2 is a diagram of an ice thermal storage air conditioning system using bleed-in.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Ice heat storage tank 2 Air heat source heat pump 3 Outside air processing air conditioner (outside air conditioner) 4 Lower blow fan coil unit (FCU) 5 Antifreeze liquid-water heat exchanger (secondary heat exchanger) 6 Heat source pump 7 Outside air conditioner Pump 8 FCU pump (secondary pump) 9 Three-way valve (for controlling heat source supplied to external controller) 10 Three-way valve (for controlling temperature of heat medium supplied to FCU) 11 Two-way valve (for controlling room temperature) Reference Signs List 12 Thermostat (for detecting supply outside air temperature) 13 Thermostat (for detecting temperature of heat medium supplied to FCU) 14 Thermostat (for detecting room temperature) 15 Humidistat (for detecting indoor humidity) 16 Heat exchanger for ice generation 17 Compression Machine 18 Condenser 19 Evaporator 20 Refrigerant switching 4-way valve 21 Throttle device (expansion valve) 22 Air brine heat exchanger (Air conditioning coil) 23 Outside air intake 24 Supply air § down 25 air over the cold water heat exchanger (coil) 26 outlet 27 the suction opening 28 floor 29 outside air supply duct 30 brine flow direction arrow (when the heat storage) 31 brine flow direction arrow (heat radiation)

Claims (3)

[Claims] An ice freezing heat exchanger provided in an ice heat storage tank, wherein an antifreeze cooled to 0 ° C. or lower is circulated by a heat source pump using a refrigerator capable of generating ice during ice heat storage.
The ice is generated by passing the ice through an air conditioner 16, and at the time of air conditioning, the antifreeze liquid is cooled by passing through an ice-generation heat exchanger 16 provided in the ice heat storage tank 1 using the external conditioner pump 7.
The ice is characterized in that heat is exchanged with the outside air through the heat exchanger 22 of the outside air conditioner 3, the heat medium of the FCU system is further cooled through the heat exchanger 5, and reaches the heat exchanger 16 for generating ice in the ice storage tank. Heat storage air conditioning system. 2. An ice storage air conditioning system according to claim 1, wherein the heat exchanger 5 is omitted and a bleed-in system is adopted. 3. The FCU according to claim 1 or 2,
An ice storage air-conditioning system characterized by using a lower blow fan coil unit for the system FCU.