JPH0686946B2 - Air conditioner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Objects of the invention In a factory having equipment that generates high heat, workers are greatly distressed in the summer. In the past, glue was applied to improve ventilation in the factory, but this was not sufficient from the viewpoint of protecting the health of workers. Therefore, in recent years, generally, the entire factory is often cooled. However, in a factory having a device that generates a large amount of heat, such as an electric furnace, the cooling load is very large, and the investment and operating costs of the cooling device are a heavy burden.

An object of the present invention is to reduce the refrigeration load of a cooling device in a factory having a large amount of equipment that generates high heat.

Conventional technology and its problems When cooling a factory that has heat-generating equipment, if the amount of heat generated is not so large, it may be possible to use a general cooling method in which the entire amount of air in the factory is circulated through a cooling device using a refrigerator. Many. However, in factories that have equipment that generates a large amount of heat, this cooling method requires a large refrigeration system, which increases investment and operating costs.

That is, in a factory that generates a large amount of heat, the air near the upper ceiling of the factory space becomes extremely hot, so the air cooled by the refrigerator is forcibly sent from the outside to the floor surface at the lower part of the factory. The amount of high-temperature air that is equivalent to the amount of air drifted to the lower part of the factory is discharged from the vicinity of the ceiling to the outside.

In this method, air equivalent to the amount of air released is taken in from the outside, cooled by a refrigerator and sent to the lower space of the factory, but in summer, the outside air taken in has a high temperature and humidity, and if cooled, it is inevitable. Since the dehumidification is performed, the latent heat load used for the dehumidification is much larger than the sensible heat load, which imposes a heavy burden on the refrigerator.

Means for Solving the Problems The present invention, in a factory having equipment that generates a large amount and high heat, circulates the entire amount of air in the factory through a cooling device without taking in outside air, and is drawn from near the upper ceiling of the factory. The hot air is first cooled by the outside air through the air-to-air heat exchanger, then secondly cooled by the refrigerator and sent to the vicinity of the lower floor surface in the factory, thus reducing the refrigeration load. It is a thing. That is, without introducing a large refrigeration load to dehumidifying latent heat as in the case of introducing outside air and cooling it with a refrigerator and sending it into the factory, in the case of full circulation of factory air, the total amount of heat generated in the factory is The refrigerator can be much smaller than the absorption method by the refrigerator.

Examples Hereinafter, examples will be described in detail.

The attached drawing is a conceptual diagram of the embodiment.

In the attached drawings, 1 is a vertical cross section of a factory building, which is simply shown as a rectangle. Reference numeral 2 denotes a device that generates heat, and is depicted as four rectangles of the same shape for simplicity. Reference numeral 3 denotes a plurality of air suction ports provided near the ceiling of the upper part of the building, which sucks the air in the upper part of the building as indicated by an arrow 4 and collectively introduces it into the heat exchanger 6 by the duct 5. Since the devices 2 each generate a large amount of heat, the air in the vicinity thereof is heated and gradually rises as shown by an arrow 7 to gather near the ceiling.
Since the air inlet 3 near the ceiling sucks in the heated air, the air entering the heat exchanger 6 from the duct 5 has a high temperature, for example, about 60 °. The heat exchanger 6 heat-exchanges the high-temperature air with the outside air (usually about 30 to 35 ° C. in summer) to about 40 ° C., and passes it as circulating air through the duct 8. The outside air is sucked in by the duct 9 and exchanges heat with the hot circulating air in the heat exchanger 6, and the temperature becomes, for example, around 50 ° C. and the blower.
It is discharged to the outside at 10.

The circulating air passing through the duct 8 as indicated by the arrow 11 is the air cooler 12.
It is cooled through the blower 13
Is sucked into. The cold air exiting the blower 13 passes through the side wall duct or the underfloor duct 14 of the factory and blows out from the ventilation opening 15 on the lower side wall or floor as shown by the arrow 16, and floats in the lower part of the factory. Since workers are standing on the factory floor, they can touch the floating cold air and feel comfortable. The cold air thus floats in the lower part of the factory, but when it touches a device that generates heat, the temperature rises rapidly and rises as shown by arrow 7 toward the ceiling. The air cooler 12 is a refrigerant-to-air heat exchanger that cools the circulating air by the refrigerator 17.

In this way, the hot air rising near the factory ceiling is first cooled to some extent by the outside air, then secondly cooled by the air cooler by the refrigerator and sent to the lower part of the factory for circulation. The power of the refrigerator is surely reduced as compared with the method of only cooling by the refrigerator without primary cooling. In addition, the method of introducing outside air, cooling it and sending it to the lower part of the factory, and discharging hot air in an amount equivalent to the introduced air from the vicinity of the ceiling to the outside is inevitably dehumidified if it is cooled, and its latent heat Therefore, the required power of the refrigerator becomes larger than that of the method according to the present invention. In this respect, the method of the present invention is extremely effective.

The advantages will be described below by numerical calculation of the embodiment.

The factory building is 50m wide, 100m long and 7m high. And the cooling load is assumed to be as follows.

Building load 50,000 Kcal / hr Lighting load 50,000 Kcal / hr Equipment waste heat load 860,000 Kcal / hr (1,000 KW) Total 960,000 Kcal / hr Factory air is circulated 3 times for 1 hour, and the flow rate is calculated to be 50 m × 100m × 7m = 35,000m ³ 35,000m ³ × 3 times / hour = 105,000m ³ / hour. If the average specific heat of air per cubic rice is 0.26 Kcal / m ³ · ℃ between 25 ℃ and 60 ℃, the temperature rise Δt of the air in the factory is Δt = 960,000 Kcal / hour ÷ (0.26 Kcal / m ³・ ℃ × 105,000m ³ / hour) = 35 ℃. If the temperature at which the circulating air enters the factory is set to 25 ° C, the temperature of the air heated in the factory and accumulated near the ceiling will be 25 + 35 = 60 ° C. Assuming that the outside air temperature is 33 ° C., 60 ° C. air drawn out from the vicinity of the ceiling is heat-exchanged with the outside air by the heat exchanger 6, so that the temperature can be cooled from 60 ° C. to 40 ° C. 40
The air of ℃ is cooled to 25 ℃ by the air cooler 12 by the refrigerator 17, and the air is circulated by blowing it into the lower part of the factory as described above. Then, the amount of heat removed by the refrigerator 17 is (40-25). ^{℃ × 0.26Kcal / m 3 · ℃} × 105,000m 3 · ℃ × 105,0
00m ³ / hour = 410,000Kcal / hour. Refrigerator capacity is 410,000 Kcal / hr ÷ 3,000 Kcal / hr. KW = 13
It is 7KW. Total heat without primary cooling by outside air
If 960,000 Kcal / hour is removed by the refrigerator, the refrigerator capacity is 960,000 Kcal / hour ÷ 3,000 / hour KW = 320KW. Will be enough.

Also, the case where outside air is taken in, cooled in a refrigerator, brought to 25 ° C, blown into the lower part of the factory, and a high-temperature air of an amount equivalent to that amount is discharged from the vicinity of the ceiling to the outside is calculated as follows.

Assuming that the air temperature near the ceiling is also 60 ° C and that it is released to the outside world, the amount is 10% as in the case of circulation.
It is 5,000 m ³ / hour. Therefore, the outside air taken in is also 10
It is 5,000 m ³ / hour. If the outside air has a temperature of 33 ° C and a humidity of 72% and the refrigerating capacity required for cooling it to 25 ° C, 90% is calculated, the enthalpy of air at 33 ° C, 72% is 22 Kcal / Ka. 25 ° C., 90% air enthalpy 17Kcal / Ka (22-17) Kcal / Kg × 105,000m 3 / hour × 1.1Kg / m ³ = 578,000Kcal / hr 578,000Kcal / hr ÷ 3,000 kcal / hr · KW = 193KW Becomes On the other hand, in the case of the present invention, 137KW / 193KW = 0.71, that is, 71% of capacity is sufficient.

As is clear from the above explanation, in an apparatus for cooling a factory that has a large amount of equipment such as an electric furnace, the high temperature air that rises and stays near the upper ceiling of the factory building is drawn out to an air-to-air heat exchanger. Put it in and cool it by the outside air,
Next, secondary cooling is performed by an air cooler with a refrigerator and returned to the lower part of the factory. In this way, if the factory air is completely circulated and two-stage cooling is performed with the outside air and the refrigerator, it is possible to use The same degree of cooling effect can be exhibited in a refrigerator with a small power, and the present invention brings a great effect to the field.

[Brief description of drawings]

The attached drawing is a conceptual diagram of an embodiment of the present invention. 1 ... longitudinal section of factory building, 2 ... heat-generating equipment, 3 ... air inlet, 5 ... duct, 6 ... air-to-air heat exchanger,
8 ... Duct, 9 ... Outside air intake duct, 10 ... Blower, 12 ... Air cooler for cooling circulating air by refrigerator, 13 ... Blower, 14 ... Duct, 15 ... Air outlet, 17 ...... Refrigerator, 4,7,11,16 …… Arrows showing air flow.

Claims (1)

[Claims] 1. In an apparatus for cooling a factory having an electric furnace or other equipment that generates a large amount of heat, high temperature air that rises and stays near the upper ceiling of the factory building is drawn out and put into an air-to-air heat exchanger to open air. It is characterized in that primary cooling is performed by the following, and then secondary cooling is performed by an air cooler using a refrigerator and returned to the lower part of the factory, and thus the factory air is completely circulated and two-stage cooling is performed by the outside air and the refrigerator. Air conditioner.