JP4348531B2 - Dehumidifying air conditioner - Google Patents

Description

  The present invention relates to a dehumidifying air-conditioning apparatus using a moisture adsorbent such as silica gel or zeolite, and in particular, provides an apparatus having improved overall thermal efficiency by utilizing exhaust heat of a fuel cell.

  The dehumidifying air conditioner performs dehumidification by using a moisture adsorbent, and the energy saving effect is enhanced by using exhaust heat discharged from a generator or a fuel cell.

  In addition, dehumidification can reduce indoor humidity compared to air conditioning using only refrigerator air conditioners, and it is rapidly spreading because it can improve comfort and prevent cooling disease, especially in summer. .

As much as possible, such a dehumidifying air conditioner is required to develop a device that uses exhaust heat generated by a fuel cell or the like. An example of such a technique is disclosed in Patent Document 1.
JP 2001-193966 A

  Patent Document 1 discloses that the heat discharged from all of the off-gas burner, fuel cell, and fuel reformer of the fuel cell is taken out as hot water, and this hot water is temporarily stored in a tank, which is removed from the dehumidifying rotor of the dehumidifying air conditioner. It was used to create hot air for use.

  However, although what is disclosed in Patent Document 1 effectively uses the exhaust heat exhausted by the fuel cell, the exhaust heat of the fuel cell is low in temperature and the dehumidifying air conditioner is There is a problem that it is difficult to increase efficiency.

  That is, as the power generation efficiency of the fuel cell is improved, the temperature of the exhaust heat exhausted together with the amount of heat exhausted from the fuel cell is decreasing. For this reason, exhaust heat becomes increasingly difficult to use, and Patent Document 1 does not disclose how to effectively use exhaust heat having a low temperature.

  Further, even the one described in Patent Document 1 has a problem that the exhaust heat of the fuel cell has not been effectively utilized yet and higher efficiency is desired.

  An object of the present invention is to provide a dehumidifying air conditioner that can effectively use heat discharged from a fuel cell and can increase dehumidifying efficiency even with exhaust heat from a fuel cell having a low temperature.

  In order to solve the above-described problems, the present invention provides a first heat exchanger for exchanging heat between a heat medium that is emitted from a heat exchanger for heating that generates high-temperature air to desorb a dehumidifying rotor and off-gas, and the off-gas has. The latent heat is recovered, the first hot water coil is heated with the recovered heat, the second hot water coil is heated with the recovered heat recovered from the preheating of the fuel cell or reformer, and the rotation direction of the dehumidification rotor in the desorption zone of the dehumidification rotor On the other hand, the first hot water coil and the second hot water coil are arranged in this order, and the temperature of the desorption zone is sequentially raised with respect to the rotation direction of the dehumidifying rotor.

  Since the dehumidifying air-conditioning apparatus of the present invention is configured as described above, it can recover even the latent heat of the offgas, and the thermal efficiency is extremely high. In addition, by using the exhaust heat of the entire fuel cell system including the reformer and the fuel cell in order from the lowest temperature in accordance with the rotation direction of the dehumidification rotor, the desorption effect of the dehumidification rotor can be enhanced, and thus the thermal efficiency is high A dehumidifying air conditioner can be provided.

  Furthermore, since moisture contained in the exhaust from the fuel cell system is largely removed by condensation, for example, when the fuel cell system is used for home use, the moisture in the gas discharged from the fuel cell system causes There is no condensation on the walls and no damage to the building.

  The invention according to claim 1 of the present invention includes a dehumidification rotor and a fuel cell, and exchanges heat between the off-gas emitted from the fuel cell and the heat medium exiting the first heater for heating the desorption zone of the dehumidification rotor. And a second heat exchanger for exchanging heat between the exhaust heat of the fuel cell and the heat medium exiting the second heater for heating the desorption zone of the dehumidification rotor, and the rotation of the dehumidification rotor The first heater is disposed on the upper side with respect to the direction, the second heater is disposed on the lower side, and the temperature of the desorption zone is sequentially increased with respect to the rotation direction of the dehumidification rotor, thereby reducing the temperature. However, it has the effect | action that a dehumidification rotor can be attached or detached effectively.

Hereinafter, embodiments of the dehumidifying air-conditioning apparatus of the present invention will be described in detail with reference to the drawings. 1-3 shows Example 1 of the dehumidification air-conditioning apparatus of this invention. FIG. 3 is a side sectional view of Embodiment 1 of the dehumidifying air conditioner of the present invention. In FIG. 3, reference numeral 1 denotes a cabinet, which is largely divided into two parts in the vertical direction, in which the dehumidifying rotor 2 and the sensible heat exchange rotor 3 are accommodated.
The dehumidifying rotor 2 is formed by forming ceramic paper or the like into a honeycomb (honeycomb) shape and synthesizing silica gel there. The sensible heat exchange rotor 3 is an aluminum sheet formed in a honeycomb shape. And the dehumidification rotor 2 and the sensible heat exchange rotor 3 are each rotationally driven by a geared motor (not shown).
Reference numerals 4 and 5 denote blowers, and the blower 4 sends outside air OA to the adsorption zone 6 of the dehumidifying rotor 2. The blower 5 discharges air from the desorption zone 7 of the dehumidifying rotor 2 to the atmosphere as exhaust EA.

  A sprayer 8 sprays water onto the sensible heat exchange rotor 3. Reference numerals 9 to 11 denote hot water coils, which are provided in the desorption zone 7 and are attached to the hot water coil 9, the hot water coil 10, and the hot water coil 11 in order from the top in the rotational direction of the dehumidifying rotor 2. Here, the hot water coils 9 to 11 are generally commercially available, and are composed of pipes such as copper and heat radiating fins made of an aluminum sheet.

  Referring to FIG. 1, reference numeral 12 denotes a fuel cell unit, which includes, for example, a reformer 13 that takes out hydrogen by reforming natural gas (LNG) or liquefied petroleum gas (LPG), a fuel cell 14, an offgas burner 15, and the like. Become. Many of these fuel cell units 12 have already been proposed and are well known, so detailed description thereof will be omitted.

  The fuel cell unit 12 is provided with first to third heat exchangers 16 to 18 for recovering exhaust heat from the reformer 13, the fuel cell 14, and the offgas / burner 15. A third heat exchanger 18 that recovers the exhaust heat of the offgas burner 15 is provided at the exhaust port 19 of the offgas burner 15.

  The hot water coil 9 is connected to the first heat exchanger 16, the hot water coil 10 is connected to the second heat exchanger 17, and the hot water coil 12 is connected to the third heat exchanger 18.

  The configuration of the first embodiment of the dehumidifying air conditioner of the present invention is as described above, and the operation thereof will be described below. First, the preheat burner (not shown) of the reformer 13 of the fuel cell unit 12 is ignited and the operation of the reformer 13 is started.

  As a result, hydrogen can be extracted from LNG or LPG, and the fuel cell 14 starts to operate. Here, when warm water is supplied from the boiler 20 to the second heat exchanger 17 and preheated, the operation start of the fuel cell 14 is accelerated.

  The fuel cell 14 operates and generates electricity from hydrogen, but the hydrogen not consumed by the fuel cell 14 is burned by the off-gas burner 15. At the same time, carbon monoxide generated in the reformer 13 is also burned and becomes harmless carbon dioxide, which is discharged from the exhaust port 19 of the off-gas burner 15 to the atmosphere.

Next, the outside air OA is sent to the adsorption zone 6 of the dehumidifying rotor 2 by the blower 4. The outside air becomes dry air in the adsorption zone 6 and the temperature rises due to heat of adsorption.
The dry air whose temperature has risen is deprived of heat while passing through the sensible heat exchange rotor 3, and the temperature is lowered to become comfortable low-temperature dry air and sent to the room (not shown) as the supply air SA.
The return air RA from the room passes around the nebulizer 8. At this time, the sprayer 8 sprays water and lowers the temperature of the return air RA by the heat of vaporization of water. Since dry air is sent to the room, the humidity of the return air RA is low and the temperature is sufficiently lowered by vaporization of water.
The return air RA whose temperature has decreased passes through the sensible heat exchange rotor 3, lowers the temperature of the sensible heat exchange rotor 3, and the temperature of the return air RA increases. The raised return air RA reaches the hot water coils 9 to 11.
FIG. 1 is a top view of the first embodiment, and as can be seen from FIG. 11 is attached.

  The return air RA that has reached the hot water coils 9 to 11 rises in temperature by passing through the hot water coils 9 to 11. The hot water coil 9 is supplied with hot water whose temperature has been raised by a third heat exchanger 18 that exchanges heat with the gas exiting from the exhaust port 19 of the off-gas burner 15.

  The gas exiting the exhaust port 19 of the off-gas burner 15 contains a lot of moisture, and the temperature between the hot water coil 9 and the third heat exchanger 18 is set so that the temperature of the third heat exchanger 18 is lower than the dew point of the off-gas. Ensure sufficient amount of hot water circulation. As a result, moisture in the off-gas is condensed in the third heat exchanger 18. That is, the hot water passing through the third heat exchanger 18 is heated by the latent heat of the gas exiting from the exhaust port 19 of the offgas burner 15.

  The third heat exchanger 18 may be provided with a drain pan (not shown) that receives condensed water. And the absolute humidity of the gas released into the atmosphere through the third heat exchanger 18 becomes low. The hot water heated by the third heat exchanger 18 flows into the hot water coil 9 and heats the air passing there.

  Moreover, the warm water which passed the 2nd heat exchanger 17 which cools the fuel cell 14 flows into the warm water coil 10, and this also heats the air which passes here. Similarly, the hot water that has passed through the first heat exchanger 16 that cools the reformer 13 flows into the hot water coil 11, which also heats the air that passes through it.

  Here, the temperature relationship of the hot water coils 9 to 11 is as follows: hot water coil 9 <warm water coil 10 <warm water coil 11. As a result, a temperature distribution in the desorption zone 7 is created.

FIG. 1 also shows a graph showing the temperature distribution of air entering the dehumidifying rotor 2 at the left end. The horizontal axis of this graph represents temperature, and the temperature increases toward the right. The vertical axis of this graph corresponds to the position on the dehumidification rotor 2.
As shown in the graph of FIG. 1, the rotation direction of the dehumidification rotor 2 is the direction of the block arrow in FIG. 1. The dehumidifying rotor 2 contains a lot of moisture when entering the desorption zone 7, and desorption proceeds even at a low temperature.

Then, the humidity gradually decreases in the desorption zone 7, but the temperature of the air used for desorption gradually increases. As a result, the portion of the dehumidifying rotor 2 that is easily desorbed is desorbed at a low temperature, and the portion that is difficult to desorb is desorbed at a high temperature, so that desorption proceeds even with a small amount of energy.
Thus, the efficiency of the fuel cell unit 12 is improved, and the exhaust heat can be used effectively even if the exhaust heat exhausted decreases. In addition, although the dimension of the hot water coils 9-11 is not demonstrated in the above Example, about the hot water coil 11 in the lower side of the rotation direction of the dehumidification rotor 2, it is good to set it as a dimension in which temperature becomes high especially. That is, when the temperature of the hot water flowing through the hot water coil 11 is high and the flow rate is small, the dimensions are made smaller than those of the other hot water coils 9 and 10 so that the temperature of the air passing through the hot water coil 11 is as high as possible.

  In the above embodiment, the off-gas burner 15 is shown. However, the off-gas burner 15 is not necessary depending on the fuel cell unit 12, and in this case, the first gas gas is discharged from the fuel cell unit to take out the latent heat of the atmosphere. A heat exchanger should be installed.

  The present invention provides a dehumidifying air conditioner that can effectively use the heat discharged from a fuel cell and can increase the dehumidifying efficiency even with the exhaust heat of a fuel cell having a low temperature.

It is a systematic diagram which shows the Example of the dehumidification air conditioning apparatus of this invention. It is a perspective view which shows the Example principal part of the dehumidification air conditioning apparatus of this invention. It is sectional drawing which shows the Example of the dehumidification air conditioning apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Cabinet 2 Dehumidification rotor 3 Sensible heat exchange rotor 4 Blower 5 Blower 6 Adsorption zone 7 Desorption zone 8 Sprayer 9 Hot water coil 10 Hot water coil 11 Hot water coil 12 Hot water coil 12 Fuel cell unit 13 Reformer 14 Fuel cell 15 Off-gas burner 16 heat exchanger 17 heat exchanger 18 heat exchanger 19 exhaust port 20 boiler

Claims (3)

A dehumidification rotor and a fuel cell are provided, and a first heat exchanger is provided for exchanging heat between the off gas emitted from the fuel cell and the heat medium emitted from the first heater for heating the desorption zone of the dehumidification rotor, and further the fuel cell A second heat exchanger for exchanging heat between the exhaust heat of the dehumidification rotor and the heat medium exiting the second heater for heating the desorption zone of the dehumidification rotor is provided, and the first heater is located on the upper side with respect to the rotation direction of the dehumidification rotor And a second heater on the lower side so that the temperature of the desorption zone is sequentially increased with respect to the rotation direction of the dehumidifying rotor , and hot water is supplied to the second heat exchanger at the start of operation of the fuel cell. A dehumidifying air conditioner provided with a boiler that supplies the fuel cell so as to preheat the fuel cell .

The dehumidifying air-conditioning apparatus according to claim 1, wherein the temperature of the first heat exchanger is set to be equal to or lower than a dew point of off-gas emitted from the fuel cell. The dehumidifying air conditioner according to claim 1, further comprising a boiler for supplying hot water for preheating the fuel cell.

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