JP4372977B2 - Special gas dehumidifier - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a dehumidifying device that dehumidifies special gas that needs to be blocked from contact with the outside in a completely sealed state.
[0002]
[Problems to be solved by the invention]
Special gases that need to be blocked from contact with the outside include, for example, toxic gases and those that are required to be in a deoxygenated state. Some are required to be kept in
[0003]
For example, DX gas used as an atmosphere gas when performing heat treatment of metal is a modified gas generated by incomplete combustion of a hydrocarbon gas such as LPG under low oxygen conditions. If it is contained and leaks into the atmosphere, it must be treated in a sealed state to cause carbon monoxide poisoning, and oxygen is included to prevent the metal from oxidizing during heat treatment and to reduce the metal surface. It is required that no deoxygenation is maintained and that it does not contain humidity.
[0004]
3 and 4 show a conventional DX gas generator that generates and dehumidifies the DX gas.
[0005]
3 and 4, in the production of DX gas in the conventional DX gas generator, a raw material gas such as propane gas and combustion air are supplied to the combustion furnace 1 from the air gas mixer 2, and this raw material gas is used as the combustion furnace 1. It is carried out by incomplete combustion in a low oxygen state.
[0006]
Then, the DX gas generated in the combustion furnace 1 is primarily cooled by the gas cooler 3, further defrosted and dehumidified by the refrigerator 4, and then guided to the dehumidifier 5.
[0007]
The dehumidifier 5 dehumidifies DX gas conducted from the refrigerator 4 and includes two adsorption towers 5A and 5B filled with silica-alumina-based adsorbent. By switching V2, DX gas from the refrigerator 4 is alternately conducted to the adsorption towers 5A and 5B every predetermined time (for example, 8 hours), and moisture is adsorbed by the adsorbent to dehumidify the DX gas. .
[0008]
A regeneration gas circuit C including a regeneration gas cooler 6, a circulation fan 7, and a heater 8 is connected to the switching valves V1 and V2. The regeneration gas heated by the switching of the switching valves V1 and V2 (for example, , DX gas) is conducted to the other adsorption tower of the adsorption towers 5A and 5B where the DX gas is not conducted, and the desorption of the DX gas is completed by this regeneration gas. Alternatively, moisture is desorbed from the adsorbent in 5B, and the adsorbent is regenerated.
[0009]
The moisture desorbed from the adsorbent of the adsorption tower 5A or 5B is condensed and drained by the regeneration gas being cooled by the regeneration gas cooler 6 of the regeneration gas circuit C, and the regeneration gas from which the moisture has been removed is circulated. After being sent to the heater 8 by the fan 7 and heated to a predetermined temperature in the heater 8, it is conducted to the adsorption tower 5A or 5B again.
[0010]
As described above, this DX gas generation apparatus generates DX gas with extremely low humidity and supplies it to an annealing furnace or the like that performs heat treatment of metal.
However, the conventional DX gas generator having the above-described configuration has the following problems.
[0011]
That is, for the production of DX gas, a very severe accuracy is required such that the dew point of the produced DX gas is, for example, −40 ° C. However, as described above, the conventional DX gas production apparatus has two units. A so-called continuous batch system in which the adsorption towers 5A and 5B are alternately switched at regular intervals and the adsorbent of the other adsorption tower 5A or 5B is regenerated while moisture is adsorbed by the one adsorption tower 5A or 5B. Since the dehumidification of the DX gas is performed by this, the dehumidification amount varies at the time of switching between the adsorption towers 5A and 5B, and it is difficult to always stably generate the DX gas having the required extremely low humidity. There is a problem.
[0012]
Further, when the regeneration gas is circulated in the regeneration gas circuit C, the conventional DX gas generation apparatus heats the adsorption towers 5A and 5B for desorption of moisture, and further drains the desorbed moisture. In order to repeat the heating and cooling steps of cooling, there is a problem that a very large amount of heat is required and the operating cost becomes high.
[0013]
Such a problem is not limited to the DX gas dehumidifier as described above, but also applies to a dehumidifier that performs dehumidification of other special gases that require sealing and require extremely low humidity.
[0014]
This invention is made in order to solve the problem which the conventional dehumidification apparatus which dehumidifies as mentioned above has.
That is, an object of the present invention is to provide a dehumidifying apparatus that can always perform dehumidification stably and at low operating cost when performing dehumidification of special gas that requires hermeticity.
[0015]
[Means for Solving the Problems]
A special gas dehumidifying device according to a first aspect of the present invention is a special gas dehumidifying device that requires processing in a sealed state in order to achieve the above object, and includes a special gas flow path through which the special gas is circulated. The desorption side regeneration gas passage and the cooling side regeneration gas passage through which the regeneration gas is circulated are formed, and are rotated around the axis and have an adsorbent inside. The filled desiccant rotor blocks the special gas flow channel, the desorption-side regeneration gas flow channel, and the cooling-side regeneration gas flow channel, and the filled adsorbent rotates from the special gas flow channel as it rotates. A desorption side regeneration gas channel and a cooling side regeneration channel are arranged so as to sequentially pass through the respective channels, and a special gas supply member for supplying a special gas to the special gas channel is connected to the desorption side. Regenerative gas flow path A heating member that heats the regeneration gas that circulates in the regeneration gas circulation channel is connected to the upstream side of the sicant rotor, and circulates in the regeneration gas circulation channel downstream of the desiccant rotor of the cooling side regeneration gas channel. A cooling member that cools the regeneration gas and a velocity energy addition member that adds velocity energy to the regeneration gas are connected.
[0016]
In the special gas dehumidifier according to the first aspect of the present invention, the desiccant rotor is rotated about its axis, and the adsorbent filled is removed from the special gas flow path to the desorption side regeneration gas flow path and the cooling side regeneration flow path. Special gas such as DX gas to be dehumidified is supplied from the special gas supply member into the special gas flow passage while the gas passes through the flow passages in order, and the regenerative gas passes through the regenerative gas circulation flow passage. It is circulated by applying velocity energy by the velocity energy adding member.
[0017]
As a result, when the special gas flowing through the special gas flow path passes through the portion located so as to block the special gas flow path of the desiccant rotor, it is contained in the special gas by the adsorbent in the desiccant rotor. Moisture is adsorbed and the special gas is dehumidified.
[0018]
The portion of the desiccant rotor filled with the adsorbent that adsorbs the moisture contained in the special gas in the special gas flow path is sequentially desorbed to constitute the regeneration gas circulation flow path as the desiccant rotor rotates. It moves into the side regeneration gas channel.
[0019]
Then, the regeneration gas heated by the heating member passes through a portion located in the desorption side regeneration gas flow channel so as to block the desorption side regeneration gas flow channel of the desiccant rotor. Moisture adsorbed on the adsorbent is desorbed.
[0020]
Next, the portion of the desiccant rotor filled with the adsorbent from which moisture has been desorbed in the desorption side regeneration gas flow path sequentially forms the regeneration gas circulation flow path as the desiccant rotor rotates. Move into the gas flow path.
[0021]
Moisture desorbed from the adsorbent of the desiccant rotor flows along with the regeneration gas in the regeneration gas circulation flow path, flows into the cooling member, and is cooled and condensed by the cooling member to be removed from the regeneration gas.
[0022]
The regeneration gas that has been cooled by the cooling member and from which moisture has been removed passes through a portion of the cooling-side regeneration gas channel that is positioned to block the cooling-side regeneration gas channel of the desiccant rotor.
[0023]
As a result, the adsorbent heated by the high-temperature regeneration gas is cooled in the desorption side regeneration gas flow path of the desiccant rotor, and the temperature of the regeneration gas rises due to the heat of the adsorbent.
[0024]
In this way, the adsorbent filled in the desiccant rotor is regenerated by adsorbing moisture in the special gas flow path and then sequentially passing through the desorption side regenerative gas flow path and the cooling side regenerative gas flow path. Again, the special gas is dehumidified by being moved into the special gas flow path.
[0025]
As described above, the regeneration gas heated by the heat of the adsorbent in the cooling side regeneration gas passage is circulated in the regeneration gas circulation passage and further heated by the heating member. The adsorbent of the desiccant rotor is desorbed inside.
[0026]
As described above, according to the first aspect of the present invention, the adsorbent flows from the special gas channel to the desorption side regeneration gas channel and the cooling side regeneration channel in the order of rotation around the axis of the desiccant rotor. By sequentially passing through the inside, dehumidification of the special gas and regeneration of the adsorbent that has dehumidified this special gas are performed continuously without the need to switch equipment, so the dehumidification of the special gas is always stable. Can be done.
[0027]
Furthermore, the regeneration gas cooled by the cooling member passes through the portion filled with the adsorbent after desorption of the desiccant rotor and is heated by the heating member to desorb the adsorbent. The adsorbent heated at the time of desorption can be efficiently cooled, and the regenerated gas that has been cooled is warmed by the heat of the adsorbent. It is possible to reduce the amount of heat in the heating member required to raise the temperature up to the temperature required for desorption of the adsorbent, thereby reducing the operating cost.
[0028]
In order to achieve the above object, a dehumidifying device for special gas according to a second aspect of the invention includes, in addition to the configuration of the first aspect, a special gas passage between the special gas passage and the regeneration gas circulation passage. A gas inflow path for inflowing gas from the regeneration gas circulation flow path side and a gas outflow path for outflowing gas from the regeneration gas circulation flow path to the special gas flow path side are connected via open / close valves, respectively. .
[0029]
According to the special gas dehumidifier of the second aspect of the present invention, when the dehumidifier starts operation, the open / close valve is opened, and the special gas flow path and the regeneration gas circulation flow path are formed by the gas inflow path and the gas outflow path. The special gas flowing in the special gas flow path flows into the regeneration gas circulation flow path through the gas inflow path, and was in the regeneration gas circulation flow path due to the pressure of the special gas flowing in. Gas is discharged to the special gas flow path through the gas outflow path.
[0030]
As a result, the gas in the regeneration gas circulation channel can be completely replaced with the special gas, and the special gas can be used as the regeneration gas. Therefore, when dehumidifying, the special gas to be dehumidified is passed through the desiccant rotor. Thus, it is possible to prevent the mixing of other gas components.
[0031]
In order to achieve the above object, a dehumidifying device for special gas according to a third invention includes, in addition to the configuration of the first invention, in the desorption side regeneration gas flow path and the cooling side regeneration gas flow path of the desiccant rotor. It is characterized in that the areas of the respective portions that are located and through which the regeneration gas passes are set to be substantially equal to each other.
[0032]
According to the special gas dehumidifying device of the third aspect of the present invention, the regeneration gas having a constant air flow circulating in the regeneration gas circulation passage is introduced into the desorption side regeneration gas passage and the cooling side regeneration gas passage of the desiccant rotor. By setting the areas of these portions to be substantially equal to each other when passing through the respective portions that are positioned, the passage speeds thereof are substantially equal to each other, and thereby, in the regeneration gas circulation channel. Since the fluctuation of the flow rate of the regeneration gas flowing through can be reduced, desorption from the adsorbent and regeneration of the adsorbent can be performed stably.
[0033]
In order to achieve the above object, a dehumidifying device for special gas according to a fourth invention is characterized in that, in addition to the configuration of the first invention, the special gas supply member is a combustion furnace that generates DX gas. Yes.
[0034]
According to the special gas dehumidifying apparatus of the fourth aspect of the present invention, it is possible to dehumidify DX gas, which needs to be dehumidified in a completely sealed state by blocking contact with the atmosphere, in a stable state and at a low operating cost. I can do it.
[0035]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments that are considered to be most suitable for the present invention will be described in detail below with reference to the drawings.
[0036]
FIG. 1 is a connection configuration diagram illustrating an example of an embodiment of a special gas dehumidifying device according to the present invention, and FIG. 2 is a perspective view illustrating a duct configuration of the dehumidifying device in the same example.
In the following description, DX gas will be described as an example of the special gas to be dehumidified.
[0037]
1 and 2, the dehumidifying device has a desiccant rotor 10 filled with silica-alumina-based adsorbent and rotated around its axis by a driving device (not shown). As shown in FIG. It is installed in a duct D divided into roads DA, DB, and DC.
[0038]
Then, the flow path DA of the duct D is opposed to a portion (hereinafter, this portion is referred to as an adsorption zone) 10A having a lower central angle of 180 ° of the desiccant rotor 10, and this adsorption zone 10A will be described later. The DX gas flowing in the flow path DA passes through.
[0039]
In the rotational direction x of the desiccant rotor 10, the flow path DB of the duct D is opposed to a portion (hereinafter referred to as a desorption zone) 10B having a central angle of 90 ° downstream of the adsorption zone 10A, and this desorption zone 10B. As will be described later, the heated regeneration gas flowing in the flow path DB passes therethrough.
[0040]
Further, in the rotational direction x of the desiccant rotor 10, the flow path of the duct D passes through a portion 10 C having a central angle of 90 ° downstream (upstream of the adsorption zone 10 A) of the desorption zone 10 B (hereinafter referred to as a purge zone). The DC faces each other, and the cooled regeneration gas flowing in the flow path DC passes through the purge zone 10C as will be described later.
[0041]
Here, between the respective flow paths DA, DB, and DC of the duct D, the DX gas and the regeneration gas flowing through these are sealed to each other so as not to leak into the other flow paths.
[0042]
The flow path DA of the duct D constitutes a DX gas flow path L1, and a combustion furnace 11 that generates DX gas is connected to the upstream side of the duct D via a precooler 12 and a damper 13, and a heat treatment of metal is performed on the downstream side. The DX gas generated in the combustion furnace 11 and cooled to a predetermined temperature by the precooler 12 circulates in the flow path DA of the duct D and passes through the adsorption zone 10A of the desiccant rotor 10. After that, it is supplied to an annealing furnace or the like.
[0043]
The flow paths DB and DC of the duct D communicate with each other on the upstream side and the downstream side, and form a regeneration gas circulation passage L2 with the desiccant rotor 10 interposed therebetween.
[0044]
The regeneration gas circulation passage L2 formed by the flow paths DB and DC is provided with a heater 14 between the upstream side of the desorption zone 10B of the desiccant rotor 10 and the downstream side of the purge zone 10C. A cooler 15 and a blower 16 are installed between the downstream side of 10B and the upstream side of the purge zone 10C.
[0045]
Further, the connection between the precooler 12 and the damper 13 in the DX gas flow passage L1 and the blower 16 in the regeneration gas circulation passage L2 and the desiccant rotor 10 are connected by a connection flow path L3, and the open / close valve V10 is connected to the connection flow path L3. Are connected downstream of the desiccant rotor 10 in the DX gas flow path L1 and between the heater 14 and the desiccant rotor 10 in the regeneration gas circulation flow path L2 through a connection flow path L4. An open / close valve V11 is connected to the.
[0046]
Both the DX gas flow passage L1 and the regeneration gas circulation flow passage L2 are sealed from the outside.
[0047]
Next, the operation of the dehumidifier will be described.
[0048]
DX gas is generated by incomplete combustion of a raw material gas such as propane gas in a low oxygen state in the combustion furnace 11.
The DX gas is cooled to a predetermined temperature in the precooler 12, and then passes through the flow path DA that constitutes a part of the DX gas flow path L1, and the desiccant rotor 10 that rotates about the axis in the duct D Conduction is conducted to the adsorption zone 10A.
[0049]
At this time, at the start of operation of the dehumidifier, the open / close valves V10 and V11 are opened, and a part of the DX gas flowing in the DX gas flow path L1 flows into the regeneration gas circulation flow path L2 through the connection flow path L3. Due to the pressure, the gas in the regeneration gas circulation passage L2 is discharged into the DX gas passage L1 through the connection passage L4.
[0050]
Then, after a predetermined time has passed in this state, the gas in the regeneration gas circulation passage L2 is completely replaced by the DX gas introduced from the DX gas passage L1, and then the open / close valves V10 and V11 are closed. The regeneration gas circulation passage L2 is sealed.
[0051]
At this time, the DX gas flowing out through the DX gas flow passage L1 has not yet been completely dehumidified, and other gases existing in the regeneration gas circulation flow passage L2 are mixed. Because it is, it is discarded.
[0052]
The DX gas introduced into the regeneration gas circulation passage L2 is used as a regeneration gas not containing oxygen.
[0053]
As described above, when the preparatory operation is completed, the dehumidifying device regenerates the adsorbent filled in the desiccant rotor 10 with the regeneration gas (DX gas) that circulates in the regeneration gas circulation passage L2. Dehumidify the gas.
[0054]
That is, the DX gas generated in the combustion furnace 11 and cooled to a predetermined temperature by the precooler 12 passes through the adsorption zone 10A of the desiccant rotor 10 when flowing in the flow path DA, and is included in the DX gas at this time. The moisture is removed by being adsorbed by the adsorbent in the desiccant rotor 10.
[0055]
The portion of the desiccant rotor 10 located in the adsorption zone 10A sequentially moves to the desorption zone 10B as the desiccant rotor 10 rotates.
[0056]
The desorption zone 10B is adsorbed in the adsorption zone 10A from the adsorbent of the desiccant rotor 10 by passing through the regeneration gas circulation passage L2 by the blower 16 and the regeneration gas heated to a predetermined temperature by the heater 14. Moisture is desorbed.
[0057]
The moisture desorbed from the adsorbent of the desiccant rotor 10 in the desorption zone 10B is condensed and removed by cooling the regeneration gas containing the moisture by the cooler 15.
[0058]
The regeneration gas from which moisture has been removed after passing through the cooler 15 is further given velocity energy by the blower 16 and passes through the purge zone 10C of the desiccant rotor 10, and is then heated by the heater 14 and again desiccant. The adsorbent is regenerated by passing through the desorption zone 10B of the rotor 10 and desorbing moisture from the adsorbent.
[0059]
Thus, the adsorbent filled in the desiccant rotor 10 passes through the adsorbing zone 10A-desorption zone 10B-purge zone 10C-adsorption zone 10A in this order as the desiccant rotor 10 rotates. Then, moisture is adsorbed and desorbed, and DX gas is dehumidified while repeating regeneration.
[0060]
Here, the purge zone 10C is provided for cooling the adsorbent in the desiccant rotor 10 heated by the regeneration gas in the desorption zone 10B before being transferred to the adsorption zone 10A.
[0061]
That is, the adsorbent in the desiccant rotor 10 is heated by the regeneration gas heated by the heater 14 in the desorption zone 10B to evaporate the adsorbed moisture. If the adsorbent is moved to, the adsorbent is not able to sufficiently adsorb moisture immediately after moving to the adsorption zone 10A because of its high temperature.
[0062]
For this reason, by providing the purge zone 10C, the adsorbent heated in the desorption zone 10B is moved to the adsorption zone 10A after its temperature is lowered to a predetermined temperature. Stable moisture adsorption can be performed in the entire region.
[0063]
The dehumidifying device is configured such that the regeneration gas cooled by the cooler 15 is heated by the heater 14 after passing through the purge zone 10C of the desiccant rotor 10 and is conducted to the desorption zone 10B. When the generated regeneration gas passes through the purge zone 10C, it is warmed by the high-temperature adsorbent, so that the heating amount of the regeneration gas in the heater 14 can be reduced by the amount warmed in the purge zone 10C. It has a high thermal efficiency.
[0064]
On the other hand, since the adsorbent that passes through the purge zone 10C of the desiccant rotor 10 is cooled by the cooled regeneration gas that passes through the purge zone 10C, the adsorbent is surely brought to a temperature at which moisture can be adsorbed in the adsorption zone 10A. It will be cooled.
[0065]
Further, the central angle of the purge zone 10C is 90 degrees which is the same as that of the desorption zone 10B, and the flow rate of the regeneration gas circulating in the regeneration gas circulation passage L2 is constant, so that the purge zone 10C passes through the purge zone 10C. The flow rate of the regeneration gas is the same as that when passing through the desorption zone 10B.
[0066]
As a result, the speed fluctuation of the regeneration gas in the regeneration gas circulation passage L2 is reduced, and the regeneration gas can be smoothly circulated in the regeneration gas circulation passage L2.
[Brief description of the drawings]
FIG. 1 is a configuration diagram schematically showing an example in an embodiment of the present invention.
FIG. 2 is a schematic diagram for explaining the arrangement of a desiccant rotor in the same example.
FIG. 3 is a connection configuration diagram showing a conventional example.
FIG. 4 is a plan view showing the arrangement of the conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Desiccant rotor 10A ... Adsorption zone 10B ... Desorption zone 10C ... Purge zone 11 ... Combustion furnace (special gas supply member)
14: Heater (heating member)
15 ... Cooler (cooling member)
16 ... Blower (speed energy addition member)
D ... Duct DA ... Flow path (Special gas flow path)
DB ... flow path (desorption side regeneration gas flow path)
DC ... flow path (cooling side regeneration gas flow path)
L1 ... DX gas flow path (special gas flow path)
L2 ... regeneration gas circulation flow path L3 ... connection flow path (gas inflow path)
L4: Connection flow path (gas outflow path)
V10, V11 ... Open / close valve

Claims (4)

A special gas dehumidifier that requires processing in a sealed state,
The desorption side regeneration gas passage and the cooling side regeneration gas passage through which the special gas is circulated and the closed regeneration gas circulation passage and the regeneration gas are circulated are formed,
A desiccant rotor rotated about its axis and filled with an adsorbent inside blocks and fills each of the special gas channel, the desorption side regeneration gas channel, and the cooling side regeneration gas channel. As the adsorbent rotates, the adsorbent is arranged so as to pass through the respective flow passages in the order of the special gas flow passage, the desorption side regeneration gas passage, and the cooling side regeneration passage,
A special gas supply member for supplying special gas to the special gas flow path is connected,
A heating member for heating the regeneration gas circulating in the regeneration gas circulation channel is connected to the upstream side of the desiccant rotor of the desorption side regeneration gas channel,
A cooling member that cools the regeneration gas that circulates in the regeneration gas circulation channel and a velocity energy addition member that adds velocity energy to the regeneration gas are connected to the downstream side of the desiccant rotor of the cooling side regeneration gas channel.
A special gas dehumidifier. Between the special gas channel and the regeneration gas circulation channel, a gas inflow channel for allowing gas to flow from the special gas channel to the regeneration gas circulation channel side and a gas from the regeneration gas circulation channel to the special gas channel side The dehumidifying device for special gas according to claim 1, wherein the gas outflow paths are connected to each other via an open / close valve. 2. The area of each portion of the desiccant rotor that is located in the desorption side regeneration gas passage and the cooling side regeneration gas passage and through which the regeneration gas passes is set to be substantially equal to each other. Special gas dehumidifier. The dehumidifying device for special gas according to claim 1, wherein the special gas supply member is a combustion furnace that generates DX gas.

Images