JP2020058989A - Gas refining equipment and gas refining method - Google Patents

Abstract

To provide gas refining equipment which allows for reduction of total quantity of regeneration gas with simple configuration.SOLUTION: Gas refining equipment 1 is provided that comprises adsorption towers 3A, 3B, and heating devices 7 heating the adsorption towers 3A, 3B. Adsorbent layers 5, 6 in which an adsorbent for adsorbing at least one kind of removal objects are filled, are laminated inside the adsorption towers 3A, 3B. The heating devices 7 are provided in only an outer circumferential surfaces of the adsorption towers 3A, 3B corresponding to the adsorbent layer 5 in which an adsorbent having largest heat energy required for regeneration of adsorbent is filled, and a region in which the heating device 7 is not provided, is provided on at least a part of the outer circumferential surface corresponding to the adsorbent layer 5 to be heated.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gas purification device and a gas purification method.

  In the pretreatment of raw material air used for air separation, impurities such as water and carbon dioxide, nitrous oxide and hydrocarbons are removed. As a pretreatment device for removing such impurities, a gas purifying device by a temperature swing (TSA: Thermal Swing Adsorption) method, that is, a TSA device is generally used. In particular, in a TSA apparatus used as a pretreatment of raw material air, an adsorption tower is filled with two or more adsorbents, and a layer (hereinafter, also simply referred to as an adsorbent layer) composed of the respective adsorbents is used for the raw material air in the adsorption tower. The layers are stacked so as to be perpendicular to the flow direction. Specifically, in order from the side of the adsorption tower to which the raw material air is supplied, an adsorbent for removing water and then an adsorbent for removing carbon dioxide are charged, and in some cases, an adsorbent for removing nitrous oxide is further added. Fill and stack each adsorbent layer. With the TSA apparatus equipped with such an adsorption tower, a purified gas (purified air) from which the above-mentioned impurities contained in the raw material air are removed can be obtained.

  The TSA device generally has two or more adsorption towers, and while one adsorption tower adsorbs impurities to the adsorbent, the other adsorption tower regenerates the adsorbent. To regenerate the adsorbent, first, the purified gas (hereinafter also simply referred to as "heating gas") heated in the adsorption tower is supplied from the side opposite to the side to which the raw material air is supplied, and the adsorbent is filled in the adsorption tower. Each adsorbate is desorbed from the adsorbent (adsorbent layer) (hereinafter, also simply referred to as "heating step"). Then, a purified gas that is not heated (hereinafter, also simply referred to as "cooling gas") is supplied into the adsorption tower to cool the adsorbent (adsorbent layer) in the adsorption tower (hereinafter, simply referred to as "cooling step"). .

  As described above, when regenerating the adsorbent in the adsorption tower, a part (about 10 to 35% by volume) of the purified gas is used for heating and cooling the adsorbent, so that the yield of the purified gas decreases. Therefore, the TSA device is required to reduce the total amount of heating gas and cooling gas (hereinafter, also simply referred to as “regeneration gas”) used for regenerating the adsorbent.

  By the way, when a TSA device is used as a pretreatment device for air separation, 50% of the energy required to regenerate the adsorbent in the adsorption tower is desorption of adsorbed water, and 2% is adsorption. It is known that desorption of carbon dioxide and nitrous oxide is occurring and 48% is the temperature rise of the adsorbent (see Patent Document 1).

  The simplest method of reducing the total amount of regenerated gas is to raise the temperature of the heating gas supplied to the adsorption tower. However, in order to raise the temperature of the heated gas, heat resistance is required for the valve and the sealing material provided in the gas supply path, which leads to an increase in the cost of the entire apparatus.

  By the way, in the case of the pretreatment device for air separation, the heating gas flows in the adsorption tower from the adsorbent layer for removing carbon dioxide (or the adsorbent layer for removing nitrous oxide) to the adsorbent layer for removing water. . Increasing the temperature of the heating gas raises the temperature of the entire adsorbent layer, but the carbon dioxide and nitrous oxide adsorbed on the adsorbent layer for removing carbon dioxide and the adsorbent layer for removing nitrous oxide Can be desorbed at less than 100 ° C., so it is not necessary to heat these adsorbent layers to 100 ° C. or higher (see Patent Document 1).

  Patent Document 2 discloses a method of introducing heating gas into the adsorption tower from between the adsorbent layer for removing carbon dioxide and the adsorbent layer for removing water as a method for reducing such extra energy. Has been done. According to the method disclosed in Patent Document 2, there is no extra energy used for heating the adsorbent layer for removing carbon dioxide, but adsorption such as addition of a valve for introducing a heating gas from the side surface of the adsorption tower The structure of the tower needs to be changed.

  In addition, a method of supplementing the heat required for regenerating the adsorbent by a method other than heating the heated gas has been studied. For example, there is a method of supplying heat by microwave energy, installing an electric heater in the packed bed of the adsorption tower, directly energizing the adsorption tower, or flowing a heating and cooling fluid through a channel provided in the body of the adsorption tower ( See Patent Document 3). However, either method requires an auxiliary device, or the structure of the adsorption tower becomes complicated.

  On the other hand, Patent Document 4 discloses a method in which a heater is provided on the outer peripheral surface of the adsorption tower and the adsorption tower is directly heated by the heater. According to the method disclosed in Patent Document 4, it is possible to reduce the amount of heating gas used in the heating process with a simple configuration. However, no consideration has been given to the cooling process, and if it is carried out as it is, the cooling of the adsorbent in the adsorption tower is hindered and the amount of cooling gas used increases, resulting in an increase in the total amount of regenerated gas. is there.

JP, 2008-232575, A JP, 2010-210190, A JP, 2003-175311, A Sho 61-120618

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a gas purification apparatus and a gas purification method capable of reducing the total amount of regenerated gas with a simple configuration and operation.

In order to solve the above problems, the present invention has the following configurations.
[1] A gas purification device for obtaining a purified gas in which the removal target is removed from a raw material gas containing one or more removal targets by a temperature swing adsorption method,
One or more adsorption towers having a first air supply / exhaust port provided at the bottom of the tower and a second air supply / exhaust port provided at the top of the tower;
A heating device for heating the adsorption tower while covering the outer peripheral surface of the adsorption tower,
An adsorbent layer filled with an adsorbent that adsorbs at least one of the objects to be removed is provided inside the adsorption tower in a direction connecting the first air supply / exhaust port and the second air supply / exhaust port. These are stacked,
The heat energy required for the regeneration of the adsorbent corresponds to the adsorbent layer filled with the largest adsorbent, with the heating device provided only on the outer peripheral surface of the adsorption tower,
A gas purifying device, wherein a region where the heating device is not provided is provided in at least a part of the outer peripheral surface corresponding to the adsorbent layer to be heated.
[2] A region where the heating device is not provided is provided on a side that is a secondary side of the adsorbent layer when the adsorbent is regenerated in a direction connecting the first air supply / exhaust port and the second air supply / exhaust port. The gas purification apparatus according to [1], which is provided.
[3] The gas purifier according to [1] or [2], wherein the region where the heating device is not provided is provided over the entire outer circumferential surface in the circumferential direction.
[4] To cover 15 to 50% of the outer peripheral surface of the adsorption tower corresponding to the adsorbent layer to be heated in the direction connecting the first air supply / exhaust port and the second air supply / exhaust port. The gas purification device according to [3], wherein the heating device is provided.
[5] The gas purification device according to any one of [1] to [4], wherein two or more of the adsorbent layers are laminated inside the adsorption tower.
[6] Any one of [1] to [5], wherein the adsorbent layer that has the largest thermal energy required to regenerate the adsorbent is an adsorbent layer filled with an adsorbent that adsorbs water. The gas purification device according to one item.
[7] The gas purification device according to any one of [1] to [6], wherein the gas purification device is a pretreatment device for air separation.
[8] A gas purification method using the gas purification apparatus according to any one of [1] to [7],
When regenerating the adsorbent in the adsorption tower,
After heating a part of the purified gas, introduced into the adsorption tower, a heating step of heating the adsorbent in the adsorption tower to desorb the removal object from the adsorbent,
Introduced into the adsorption tower without heating a part of the purified gas, and performing a cooling step of cooling the adsorbent heated in the heating step,
A gas purification method, wherein a heating device is operated in the heating step.
[9] The gas purification method according to [8], wherein the heating device is operated only for a required time from the start of the heating step.

The gas purification apparatus and gas purification method of the present invention can reduce the total amount of regenerated gas with a simple configuration and operation.
Further, the gas purification device and the gas purification method of the present invention are particularly useful as a pretreatment device and a pretreatment method for air separation.

It is a schematic diagram which shows the structure of the gas purification apparatus which is one Embodiment to which this invention is applied.

The meanings of the following terms in the present specification are as follows.
The “refined gas” means a gas obtained by removing an object to be removed from the raw material gas by one or more adsorbents filled in the adsorption tower.
The “adsorbent layer” means a layer made of an adsorbent packed in the adsorption tower.
“Regeneration” of the adsorbent means returning the adsorbent on which the removal target is adsorbed to a state in which the removal target can be adsorbed again.
The "regeneration step" of the adsorbent is a step of heating the adsorbent filled in the adsorption tower to desorb the adsorbed adsorbate (object to be removed) (heating step) and the adsorbent in the adsorption tower. Means a general term of a step of cooling (cooling step).
The “heating gas” means a gas supplied into the adsorption tower in the heating step, that is, a heated purified gas.
The "cooling gas" means a gas supplied into the adsorption tower in the cooling step, that is, a purified gas which is not heated.
"Regeneration gas" means the gas supplied into the adsorption tower to regenerate the adsorbent in the adsorption tower, that is, the heating gas and the cooling gas.
The “exhaust gas” means a regenerated gas used for regenerating the adsorbent and means a gas discharged from the adsorption tower.

  Hereinafter, a configuration of a gas purification apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings, together with a gas purification method using the same. In the drawings used in the following description, in order to make the features easy to understand, there are cases where features are enlarged for convenience, and it is not always the case that the dimensional ratios of the components are the same as the actual ones. Absent.

<Gas purifier>
First, the configuration of a gas purifying apparatus according to an embodiment of the present invention will be described.
FIG. 1 is a schematic diagram showing an example of the configuration of a gas purifying apparatus that is an embodiment to which the present invention is applied. As shown in FIG. 1, the gas purification apparatus 1 of the present embodiment includes a compressor 2, two adsorption towers 3A and 3B, a heater 4, a heater (heating device) 7, a supply line L1, a depressurization line L2, The exhaust gas line L3, the recovery line L4, the charging line L5, the regeneration (cooling) gas line L6, and the heating line L7 are roughly configured.

  The gas purification apparatus 1 of the present embodiment is a gas purification apparatus for obtaining a purified gas by removing a removal target object from a source gas containing a removal target object by a temperature swing adsorption (hereinafter, simply referred to as “TSA”) method. Is. In the gas purification device 1, one of the two adsorption towers 3A and 3B is performing the adsorption step, while the other is performing the regeneration step, so that the purified gas is continuously obtained.

  The raw material gas is not particularly limited. The raw material gas is, for example, air containing at least one selected from the group consisting of water (water), nitrogen, nitrous oxide and carbon dioxide as an object to be removed; selected from the group consisting of carbon dioxide, water, nitrogen and air. Methane gas containing at least one kind as a removal target; hydrogen containing at least one selected from the group consisting of water, carbon dioxide, nitrogen and air as a removal target. In the gas purification device 1 of the present embodiment, an excellent effect is exhibited when the raw material gas containing water is used as the object to be removed.

  The compressor 2 is a device that compresses (pressurizes) the raw material gas and supplies it to the adsorption towers 3A and 3B via the supply line L1. The compressor 2 is not particularly limited as long as it can compress the raw material gas. As the compressor 2, a commercially available pressurizing pump such as a scroll compressor can be used.

  The adsorption towers 3A and 3B are hollow cylindrical members and have basically the same configuration. A first air supply / exhaust port 3a is provided at the bottom of the adsorption towers 3A, 3B, and lower side pipes 8a, 8b are connected thereto. A first air supply / exhaust port 3b is provided at the top of the adsorption towers 3A, 3B, and upper side pipes 9a, 9b are connected thereto.

  In the gas purification apparatus 1 of the present embodiment, of the adsorption towers 3A and 3B, in the adsorption tower in the adsorption step, the raw material gas is introduced into the adsorption tower from the first supply / exhaust port 3a, and the purified gas is supplied in the second supply / exhaust. It is discharged from the port 3b to the outside of the adsorption tower. That is, in the adsorption process, the first air supply / exhaust port 3a serves as a gas introduction port, and the second air supply / exhaust port 3b serves as a gas exhaust port. In the adsorption tower in the regeneration step of the adsorption towers 3A and 3B, the regenerated gas is introduced into the adsorption tower through the second air supply / exhaust port 3b, and the exhaust gas is discharged from the first air supply / exhaust port 3a to the outside of the adsorption tower. It That is, in the regeneration process, the second air supply / exhaust port 3b serves as a gas introduction port, and the first air supply / exhaust port 3a serves as a gas exhaust port.

  The material of the adsorption towers 3A and 3B is not particularly limited. From the viewpoint of pressure resistance and workability, it is preferable to use carbon steel, stainless steel or the like as the material of the adsorption towers 3A and 3B, and among these, stainless steel is more preferable. Since the adsorption towers 3A and 3B have the same form as described above, the following description will be made only for the adsorption tower 3A.

  The tower height (height in the axial direction) of the adsorption towers 3A and 3B is not particularly limited, and can be appropriately selected depending on the processing amount of the raw material gas, the required amount of the purified gas, and the like. The tower height of the adsorption towers 3A and 3B can be in the range of 1000 to 6000 mm, and preferably in the range of 2000 to 4000 mm.

  Inside the adsorption tower 3A, a first adsorbent layer (adsorbent layer) 5 filled with a first adsorbent (adsorbent) and a second adsorbent layer (adsorbent) filled with a second adsorbent ( And an adsorbent layer) 6 are laminated and provided. Specifically, the stacking direction of the first adsorbent layer 5 and the second adsorbent layer 6 is provided so as to connect the first air supply / exhaust port 3a and the second air supply / exhaust port 3b. In other words, the thickness directions of the first and second adsorbent layers 5 and 6 are the same as the direction connecting the first air supply / exhaust port 3a and the second air supply / exhaust port 3b. The adsorbent layer 5 and the second adsorbent layer 6 are laminated.

  The thickness (filling height) of the first and second adsorbent layers 5 and 6 is not particularly limited, and depends on the concentration of the object to be removed in the atmosphere in the adsorption tower 3A and the temperature of the atmosphere. It can be appropriately selected. As a result, the adsorption tower 3A can surely adsorb and remove the removal object contained in the raw material gas by the first and second adsorbent layers 5 and 6.

Specifically, the thickness per layer (for example, the thickness H _{5 of} the first adsorbent layer ₅ ) can be in the range of 100 to 2000 mm, and preferably in the range of 300 to 800 mm.
Further, the total filling height (that is, the total thickness of the first adsorbent layer 5 and the second adsorbent layer 6) H of the adsorbent layer can be in the range of 200 to 4000 mm, and the range of 600 to 1600 mm. It is preferable that
Further, the ratio of the total filling height H of the adsorbent layer to the tower height of the adsorption towers 3A and 3B can be in the range of 5 to 70%, preferably in the range of 20 to 50%.

  The materials of the first and second adsorbents are not particularly limited, and can be appropriately selected according to the object to be removed contained in the source gas. As materials for the first and second adsorbents, activated alumina is used for removing water in the air, NaX zeolite is used for removing carbon dioxide in methane gas, and nitrogen is used for removing nitrogen in hydrogen. Can select LiX zeolite respectively.

  The combination of the first and second adsorbents is not particularly limited and can be appropriately selected according to the type of the removal target contained in the source gas.

  In particular, when the gas purification device 1 of this embodiment is used as a pretreatment device for air separation, it is necessary to remove water and carbon dioxide as impurities in the raw material air. Therefore, it is preferable to select activated alumina and NaX zeolite as the material of the adsorbent. Further, as described above, in the gas purification device 1 of the present embodiment, the first air supply / exhaust port 3a serves as the gas inlet port and the second air supply / exhaust port 3b serves as the gas outlet port in the adsorption process. Therefore, in the adsorption tower 3A, activated alumina is used as the first adsorbent constituting the first adsorbent layer 5 provided on the first air supply / exhaust port 3a side, and the first adsorbent provided on the second air supply / exhaust port 3b side is used. It is more preferable to use NaX zeolite as the second adsorbent forming the two-adsorbent layer 6.

  The heaters 7 are provided so as to cover a part of the outer peripheral surfaces of the adsorption towers 3A and 3B in order to heat the adsorption towers 3A and 3B. As will be described later, while the heater 7 is operated in a part of the heating step in the regeneration step, the adsorbent filled inside is heated through the wall surface forming the outer peripheral surface of the adsorption towers 3A and 3B. be able to. Since the heaters 7 are provided in the adsorption towers 3A and 3B in the same manner, the following description will be given only for the adsorption tower 3A side.

  The heater 7 is provided only on a portion of the outer peripheral surface of the adsorption tower 3A, which corresponds to the adsorbent layer filled with the adsorbent having the largest thermal energy required to regenerate the adsorbent. For example, in a configuration in which the first adsorbent layer 5 for removing water and the second adsorbent layer 6 for removing carbon dioxide are stacked in the adsorption tower 3A, the first adsorbent for adsorbing water is filled. The formed first adsorbent layer 5 corresponds to the adsorbent layer to be heated. Therefore, as shown in FIG. 1, the heater 7 is provided only on the portion corresponding to the first adsorbent layer 5 on the outer peripheral surface of the adsorption tower 3A, and on the portion corresponding to the second adsorbent layer 6 only. Not provided.

  By the way, since the heating heater 7 that directly heats the adsorption tower 3A has its own heat capacity, the portion where the heating heater 7 is provided keeps the adsorption tower 3A warm. Therefore, if the heater 7 is installed on the outer peripheral surface of the adsorption tower 3A, which corresponds to the second adsorbent layer 6 filled with the second adsorbent that requires almost no energy to regenerate the adsorbent, cooling in the regeneration process is performed. In the process, it rather becomes a factor that hinders the cooling of the adsorbent in the adsorption tower 3A. Therefore, the heater 7 is installed only on the portion corresponding to the first adsorbent layer 5 on the outer peripheral surface of the adsorption tower 3A.

  In the gas purification apparatus 1 of the present embodiment, the heater 7 is installed only on the outer peripheral surface of the adsorption tower 3A corresponding to the adsorbent layer to be heated, and the adsorbent layer to be heated is At least a part of the outer peripheral surface of the corresponding adsorption tower 3A is provided with a region where the heater 7 is not provided.

  As a result, when the adsorption tower 3A is in the regeneration step, in the heating step, the heater 7 directly heats the adsorption tower 3A to supply the heat quantity necessary for heating the filled adsorbent (particularly, the first adsorbent). In the cooling step, the cooling of the adsorbent filled in the adsorption tower 3A is not hindered. Therefore, in the regeneration process of the adsorption tower 3A, it is possible to reduce the amount of heating gas used in the heating process and also reduce the amount of cooling gas used in the cooling process. As a result, the total amount of regenerated gas can be reduced.

  The position of the region where the heating heater 7 is not provided is not particularly limited, but from the viewpoint of effectively utilizing the heat energy by the heating heater 7 without discharging it, the first supply / exhaust port 3a and the second supply / exhaust port 3b of the adsorption tower 3A are used. It is preferably provided on the side that is the secondary side of the adsorbent layer to be heated when the adsorbent is regenerated in the direction of connecting with.

  Here, the direction connecting the first air supply / exhaust port 3a and the second air supply / exhaust port 3b of the adsorption tower 3A is the flow direction of gas in the adsorption tower 3A. In the present embodiment, when the adsorbent is regenerated, the second air supply / exhaust port 3b serves as a gas inlet port and the first air supply / exhaust port 3a serves as a gas exhaust port, and thus serves as a secondary side of the adsorbent layer to be heated. The side is the side of the first air supply / exhaust port 3a. Specifically, as shown in FIG. 1, it is preferable to provide a region where the heater 7 is not provided on the side of the first air supply / exhaust port 3a of the first adsorbent layer 5 to be heated.

  By the way, during the regeneration process of the adsorption tower 3A, the regeneration gas introduced into the adsorption tower 3A is directed from the upper part to the lower part of the adsorption tower 3A, that is, from the upper side to the lower side of the first adsorbent layer 5 to be heated. Flowing. Therefore, for example, even if the lower side of the first adsorbent layer 5 is heated by the heater 7, the excess heat is discharged to the outside of the adsorption tower 3A due to the gas flow, and is not effectively used for regeneration of the adsorbent. This is the same even if the entire area of the outer peripheral surface of the adsorption tower 3A corresponding to the first adsorbent layer 5 is covered with the heater 7. On the other hand, when the upper side of the first adsorbent layer 5 is heated by the heater 7 as in the present embodiment, the generated excess heat moves by heat transfer due to the gas flow, so the first adsorbent layer 5 It is effectively used to regenerate the lower first adsorbent.

  In addition, from the viewpoint of cooling efficiency of the adsorbent in the cooling step, the region where the heater 7 is not provided is preferably provided over the entire circumferential direction of the outer peripheral surface of the adsorption tower 3A.

Further, the ratio (also referred to as a coverage rate) of the area where the heater 7 is provided to the entire portion of the outer peripheral surface of the adsorption tower 3A corresponding to the first adsorbent layer 5 is not particularly limited. The amount of heat required to heat the agent (particularly, the first adsorbent) and the cooling efficiency of the adsorbent can be considered and appropriately selected. Here, the ratio (coverage) of the area where the heater 7 is provided is, as shown in FIG. 1, in the direction connecting the first supply / exhaust port 3a and the second supply / exhaust port 3b (axial direction of the adsorption tower 3A). , of the outer peripheral surface of the adsorption tower 3A, the height of the region in which the total height of the portion corresponding to the first adsorbent layer 5 (i.e., the thickness of the first adsorbent layer 5) against H _5, provided heater 7 It is calculated from the ratio of h.

  The ratio (coverage) of the region where the heater 7 is provided is preferably 15 to 50%, more preferably 25 to 45%. By setting the above preferable range, the excess heat generated by the heating by the heating heater 7 can be effectively used, and the power density of the heating heater 7 in the axial direction of the adsorption tower 3A does not become too high, and the heating heater The life of No. 7 does not become extremely short.

  The type of the heater 7 is not particularly limited as long as it can cover a part of the outer peripheral surface of the adsorption tower 3A and heat the adsorption tower 3A. As such a heater 7, a band heater, a silicon rubber heater, a mantle heater, or the like can be used, and of these, the band heater is preferably used. Further, as the heating heater 7, two or more heaters may be used at the same time, or any two or more of the above-mentioned groups may be used in combination.

  The supply line L1 is a gas distribution path provided for supplying the raw material gas containing the removal target to the adsorption towers 3A and 3B. A first end of the supply line L1 is connected to the compressor 2, and a second end of the supply line L1 is branched into a first supply branch line La1 and a second supply branch line Lb1.

  The first and second supply branch lines La1 and Lb1 are connected to the lower pipes 8a and 8b, respectively. Valves Va1 and Vb1 are provided in the first and second supply branch lines La1 and Lb1, respectively.

  The recovery line L4 is a gas flow provided to recover the purified gas from the adsorption towers 3A and 3B. The recovery line L4 has a first end branched into a first recovery branch line La4 and a second recovery branch line Lb4, and a second end connected to a storage container (not shown). The first and second recovery branch lines La4, Lb4 are connected to the upper side pipes 9a, 9b, respectively. Valves Va4 and Vb4 are provided in the first and second recovery branch lines La4 and Lb4, respectively.

  The depressurization line L2 is a gas distribution path provided for lowering the pressure in the adsorption towers 3A and 3B and performing a process called depressurization. In the depressurization step, after the object to be removed is adsorbed by the adsorbent in the adsorption towers 3A and 3B, the object to be removed is desorbed from the surface of the adsorbent by lowering the pressure in the adsorption towers 3A and 3B. .

  The depressurization line L2 has a first end branched into a first depressurization branch line La2 and a second depressurization branch line Lb2, and the second end is an open end. The first and second depressurizing branch lines La2, Lb2 are connected to the lower side pipes 8a, 8b, respectively. Valves Va2 and Vb2 are provided in the first and second depressurizing branch lines La2 and Lb2, respectively.

  The regeneration gas line L6 is a gas distribution path provided for supplying a part of the purified gas as regeneration gas to the adsorption tower to be regenerated. The regeneration gas line L6 has a first end branched to a first regeneration gas branch line La6 and a second regeneration gas branch line Lb6 at a branch point r, and a second end to a recovery line L4. It is connected. The first and second regeneration gas branch lines La6 and Lb6 are connected to the upper pipes 9a and 9b, respectively. Valves Va6 and Vb6 are provided in the first and second regeneration gas branch lines La6 and Lb6, respectively. A valve V7 is provided in the regeneration gas line L6 between the connection point p and the connection point q.

  The heating line L7 is a gas flow path provided for heating the regeneration gas. The heating line L7 has a first end connected to the regeneration gas line L6 at a connection point p and a second end connected to the regeneration gas line L6 at a connection point q. The heating line L7 is provided with the heater 4 and the valve V8 between the connection point p and the connection point q.

  The heater 4 is not particularly limited as long as it can heat the purified gas flowing through the heating line L7 to a required temperature. As the heater 4, a flange heater, a plug heater or the like can be used, and of these, the flange heater is preferably used.

  The exhaust gas line L3 is a gas distribution path provided to convey the exhaust gas discharged from the adsorption towers 3A and 3B. The exhaust gas line L3 has a first end portion branched into a first exhaust gas branch line La3 and a second exhaust gas branch line Lb3, and a second end portion is an open end. The first and second exhaust gas branch lines La3, Lb3 are connected to the lower side pipes 8a, 8b, respectively. Valves Va3 and Vb3 are provided in the first and second exhaust gas branch lines La3 and Lb3, respectively.

  The charging line L5 is a gas flow path provided for increasing the pressure in the adsorption towers 3A and 3B and performing a process called charging. In the charging step, the pressure in the adsorption towers 3A, 3B is increased to a level suitable for purifying the raw material gas after the object to be removed is desorbed from the adsorbent in the adsorption towers 3A, 3B.

  The charging line L5 has a first end branched into a first charging branch line La5 and a second charging branch line Lb5, and a second end connected to the recovery line L4. . The first and second charging branch lines La5, Lb5 are connected to the upper pipes 9a, 9b, respectively. Valves Va5 and Vb5 are provided in the first and second charging branch lines La5 and Lb5, respectively.

  As described above, the gas purification device 1 of the present embodiment has the first adsorbent layer 5 filled with the first adsorbent for removing water and the carbon dioxide removal inside the adsorption towers 3A and 3B. Second adsorbent layer 6 filled with the second adsorbent is laminated in the axial direction of the adsorption towers 3A and 3B, and the first adsorbent layer filled with the first adsorbent that adsorbs water The heaters 7 are provided only on the outer peripheral surfaces of the adsorption towers 3A, 3B corresponding to No. 5, and at least a part of the outer peripheral surfaces of the adsorption towers 3A, 3b corresponding to the first adsorbent layer 5 to be heated. In this structure, a region where the heater 7 is not provided is provided. As a result, in the regeneration process of the adsorption towers 3A and 3B, in the heating process, the heat amount required for heating the adsorbent (in particular, the first adsorbent) charged by directly heating the adsorption towers 3A and 3B by the heater 7 is provided. While being supplied, the cooling process does not hinder the cooling of the adsorbent filled in the adsorption towers 3A and 3B. Therefore, in the regeneration process of the adsorption towers 3A and 3B, it is possible to reduce the amount of heating gas used in the heating process and also reduce the amount of cooling gas used in the cooling process. As a result, according to the gas purification device 1 of the present embodiment, the total amount of regenerated gas can be reduced with a simple configuration.

  Further, according to the gas purification device 1 of the present embodiment, the heater 7 is provided on the first supply / exhaust port 3a side (downstream side of the gas flow in the adsorption towers 3A and 3B) of the first adsorbent layer 5 to be heated. In order to provide a region where no gas is provided, the upper side of the first adsorbent layer 5, which is the upstream side of the gas flow, is heated by the heater 7. It can be effectively used to regenerate the adsorbent.

  Further, according to the gas purifying apparatus 1 of the present embodiment, since the ratio (coverage) of the region where the heater 7 is provided is 15 to 50%, it is possible to effectively use the surplus heat generated by the heating by the heater 7. In addition, the life of the heater 7 can be extended.

  Further, according to the gas purification apparatus 1 of the present embodiment, when used as a pretreatment apparatus for air separation and continuously supplying purified air while reducing the total amount of regenerated gas when removing water from the raw material gas, Especially useful.

<Gas purification method>
Next, an example of the gas purification method of this embodiment using the gas purification apparatus 1 described above will be described. The gas purification method of the present embodiment will be described below by taking as an example a case where purified air obtained by removing water and carbon dioxide as raw material to be removed is obtained from raw air.

  In the following description, in the gas purification apparatus 1, the gas purification method is applied in a state where the regeneration of the adsorbent in the adsorption tower 3A is completed and the purification of the raw material air is completed in the adsorption tower 3B, and the gas is purified in the adsorption tower 3A. An example will be described in which the adsorbent in the adsorption tower 3B is regenerated while the purification (adsorption of the removal target) is performed.

(Adsorption tower 3A: purification step, adsorption tower 3B: depressurization step)
First, all the valves shown in FIG. 1 are closed. Then, the valve Va1, the valve Va4, and the valve Vb2 are opened. In this state, the raw material air compressed from the compressor 2 is supplied to the adsorption tower 3A so that the first adsorbent layer 5 in the adsorption tower 3A adsorbs water and the second adsorbent 6 adsorbs carbon dioxide, respectively. The dried purified air is recovered via the recovery branch line La4 and the recovery line L4.

  In the adsorption tower 3B, when the valve Vb2 is opened, the pressure in the adsorption tower 3B drops to near atmospheric pressure. As a result, a part of the water and carbon dioxide adsorbed by the first and second adsorbents in the adsorption tower 3B is moved to the second depressurization branch line Lb2 and the depressurization line L2 together with the gas in the adsorption tower 3B. Discharge via. Note that the heater 7 is not operated in this step.

In the refining step, the amount of the raw material gas supplied to the adsorption tower 3A is not particularly limited, but may be, for example, 1000 to 50000 Nm ³ / h. The time for which the valve Va1, the valve Va4, and the valve Vb2 are kept open is not particularly limited, but may be, for example, 2 to 20 minutes.

(Adsorption tower 3A: purification step, adsorption tower 3B: heating step 1)
Next, the valve Vb2 is closed while the valves Va1 and Va4 are open. Then, the valve Vb3, the valve Vb6, and the valve V8 are opened. In this state, the raw material air is supplied to the adsorption tower 3A, and while recovering the purified air, a part of the purified air is introduced as a regeneration gas into the heating line L7 via the regeneration gas line L6. Further, the operation of the heater 7 is started. The dry air in the heating line L7 is heated by the heater 4 and is supplied to the adsorption tower 3B as heating gas via the second regeneration gas branch line Lb6 and the like. Moreover, only the upper side of the outer peripheral surface of the adsorption tower 3B corresponding to the first adsorbent layer 5 is heated by the heater 7.

  As a result, the temperature inside the adsorption tower 3B rises, the carbon dioxide adsorbed by the second adsorbent and the water adsorbed by the first adsorbent are desorbed, and the air having a high water content and carbon dioxide concentration becomes exhaust gas. Is discharged from the adsorption tower 3B. The heat generated by the heater 7 is consumed for desorption of water in the upper portion of the first adsorbent layer 5. The exhaust gas is discharged outside the system via the second exhaust gas branch line Lb3 and the exhaust gas line L3.

  Here, the time for maintaining the valve Va1, the valve Va4, the valve Vb3, the valve Vb6, and the valve V8 in the open state is not particularly limited, but may be, for example, 30 to 180 minutes.

The heater 7 is operated only during the heating process.
The heating time by the heater 7 is not particularly limited, but it is preferable to set the necessary minimum heating time so as not to hinder the cooling in the adsorption tower 3B in the subsequent cooling step.

  By the way, if the flow velocity of the regeneration gas (heating gas and cooling gas) introduced into the adsorption tower 3B is constant, the speed at which heat moves by heat transfer is constant. Further, the length from the heater 7 installed in the portion corresponding to the upper end side of the first adsorbent layer 5 to the lower end of the first adsorbent layer 5 is the upper end of the second adsorbent layer 6 to the first adsorbent layer 5. Since it is shorter than the length to the lower end of 5, the heat given by the heated regeneration gas (heating gas) may be shorter than the time to move to the lower end of the first adsorbent layer 5.

Therefore, it is preferable that the heater 7 is operated only for a required time from the start of the heating process.
The heating time (operating time) of the heating heater 7 is as follows: “operating time of heating heater 7 = heating gas supply time (regeneration gas heating time) × (vertical length h of heating heater 7 / total adsorbent layer) Is more preferable.

  The heating temperature of the purified air by the heater 4 is not particularly limited, but may be 120 to 170 ° C., for example.

  Further, the heating temperature by the heater 7 is not particularly limited, but it is preferable to set it to the minimum necessary heating temperature that does not hinder the cooling of the adsorption tower 3B in the subsequent cooling step. The heating temperature by the heater 7 can be appropriately selected according to the thermal energy required to regenerate the adsorbent to be heated. For example, when heating the first adsorbent that adsorbs water, the heating temperature by the heater 7 is preferably 90 to 110 ° C, and more preferably 100 ° C.

(Adsorption tower 3A: purification step, adsorption tower 3B: heating step 2)
Next, the operation of the heater 7 is stopped. At this time, the raw material air is supplied to the adsorption tower 3A with the valves Va1, Va4, Vb3, Vb6, and V8 open, and the purified air is recovered while a part of the purified air is used as a regeneration gas. It is introduced into the heating line L7 via the line L6. The dry air in the heating line L7 is heated by the heater 4 and supplied to the adsorption tower 3B via the second regeneration gas branch line Lb6 and the like.

  Subsequently, the temperature in the adsorption tower 3B rises, the carbon dioxide adsorbed by the second adsorbent and the water adsorbed by the first adsorbent are desorbed, and the air having a high water content and carbon dioxide concentration becomes exhaust gas. Is discharged from the adsorption tower 3B. Although the heater 7 is stopped, the excess heat sent downward by the regeneration gas is consumed for desorption of water in the lower part of the first filler layer 5. The exhaust gas is discharged outside the system via the second exhaust gas branch line Lb3 and the exhaust gas line L3.

(Adsorption tower 3A: purification step, adsorption tower 3B: cooling step)
Next, the valve V8 is closed and the valve V7 is opened while the valves Va1, Va4, Vb3, and Vb6 are open. In this state, the raw material air is supplied to the adsorption tower 3A, and a part of the purified air is introduced into the regeneration gas line L6 as a regeneration gas (cooling gas) while recovering the dried purified air.

  The purified air in the regeneration gas line L6 is supplied as a cooling gas to the adsorption tower 3B via the valve V7. The purified air cools the inside of the adsorption tower 3B, and the temperature inside the adsorption tower 3B becomes low. The heat generated by the heater 7 is consumed for desorption of water in the first filler layer 5, and thus does not hinder the cooling of the inside of the adsorption tower 3B.

  Here, the time for maintaining the valve Va1, the valve Va4, the valve Vb3, the valve Vb6, and the valve V7 in the open state is not particularly limited, but may be, for example, 60 to 240 minutes.

(Adsorption tower 3A: purification step, adsorption tower 3B: charging step)
Next, the valve Vb3, the valve Vb6, and the valve V7 are closed while the valve Va1 and the valve Va4 are opened, and the valve Vb5 is opened. In this state, the raw material gas is supplied to the adsorption tower 3A, and a part of the purified air is introduced into the charging line L5 as a charging gas while collecting the dried purified air.

  The purified air in the charging line L5 is supplied to the adsorption tower 3B via the second charging branch line Lb5 and the like. As a result, the pressure in the adsorption tower 3B rises to a level suitable for purifying the raw material air.

  Here, the pressure of the adsorption tower 3B after the charging step is not particularly limited, but may be, for example, 300 to 1000 kPaG. In addition, the time for maintaining the valve Va1, the valve Va4, and the valve Vb5 in the open state is not particularly limited, but may be, for example, 10 to 60 minutes.

  The regeneration of the adsorbent in the adsorption tower 3B is completed through the depressurizing step, the heating step 1, the heating step 2, the cooling step, and the filling step in the adsorption tower 3B described in the above order. Next, in the gas purification method of the present embodiment, the valve Va1 and the valve Va4 are closed, and the valves Vb1 and Vb4 are opened to purify the raw material gas in the adsorption tower 3B (purification step), and the adsorbent in the adsorption tower 3A. May be regenerated (regeneration step). In this way, by repeating the purification process and the regeneration process between the adsorption tower 3A and the adsorption tower 3B, the raw material air can be continuously purified.

  As described above, in the gas purification method of the present embodiment, since the gas purification apparatus 1 described above is used, in the regeneration step of the adsorption tower (adsorbent), the heating heater 7 is operated only for a required time from the start of the heating step. The total amount of regenerated gas can be reduced by a simple operation such as operation.

  Although some embodiments of the present invention have been described above, the present invention is not limited to these particular embodiments. Further, the present invention may have additions, omissions, substitutions, and other modifications of the configuration within the scope of the gist of the present invention described in the claims.

  For example, in the gas purification device 1 of the above-described embodiment, the configuration in which the two adsorbent layers are stacked in the adsorption towers 3A and 3B has been described as an example, but the present invention is not limited thereto. The adsorbent layer in the adsorption tower may be a single layer (one layer) or may have a structure in which three or more layers are laminated.

  Further, in the gas purification device 1 of the above-described embodiment, the heater 7 is described as an example in which the heater 7 is fixed to the adsorption towers 3A and 3B, but the present invention is not limited to this. For example, the heater 7 may be provided so as to be movable with respect to the outer peripheral surfaces of the adsorption towers 3A and 3B, or may be removable. That is, on the outer peripheral surface of the adsorption tower 3A, the position and the area covered by the heater 7 may be appropriately changed.

  Further, the gas purification device 1 of the above-described embodiment has a configuration including two adsorption towers, but the present invention is not limited to this, and the number may be one or three or more.

  Hereinafter, the effect of the present invention will be specifically described with reference to test examples and comparative examples. The present invention is not limited to the following test examples and comparative examples.

<Test Example 1>
As shown in FIG. 1, the first adsorbent layer 5 in which the first adsorbent for removing water in the air is filled in the adsorption towers 3A and 3B and the second adsorbent for removing carbon dioxide in the air are provided. The filled second adsorbent layer 6 is laminated, and the heater 7 wound around only the portion corresponding to the upper end side of the first adsorbent layer 5 among the outer peripheral surfaces of the adsorption towers 3A and 3B. The two-column TSA apparatus 1 having the above-mentioned components and adsorbing and removing water and carbon dioxide in the raw material air was used.

(Operating conditions)
・ Adsorption towers 3A, 3B: φ1m x height 1m
・ First adsorbent: Activated alumina (300 mm)
・ Second adsorbent: Zeolite (300mm)
・ Heating heater: The portion corresponding to the upper half of the first adsorbent layer 5 (height 15
Wrap around 0-300mm position)
(Vertical length: 150 mm)
・ Heating heater replacement cycle: 5 years ・ Compressed air volume: 2000 Nm ³ / h
・ Compressed air pressure: 400 kPa (g)
・ Total amount of regenerated gas: 260 Nm ³ / h
・ Regeneration gas heating temperature: 150 ℃
・ Heating temperature of heater: 100 ℃
・ Cycle time: 240min
・ Adsorption: 240 min
・ Playback: 240min
・ Depressurization 10min
・ Heating 100min
(Adsorption tower heater heating 25 min) *
・ Cooling 105min
・ Charging 25min
* Operating time = Regeneration gas heating time x (Heating heater vertical direction length h / Total height of all adsorbent layers H)
= 100 x (150/600)
= 25 min

(Operating procedure)
The TSA device 1 was operated in the following procedure.
(1) Tower A: adsorption, Tower B: depressurization, heater: stopped (10 min)
Va1, Va4 and Vb2 are opened, raw material compressed air 2000 Nm ³ / h supplied from the compressor 2 is introduced from Va1 into the A tower (adsorption tower 3A), and the first layer (first adsorbent layer 5) is supplied with moisture. CO ₂ was adsorbed on the second layer (second adsorbent layer 6) to take out purified air from Va4. At the same time, the tower B was depressurized from Vb2 and depressurized to near atmospheric pressure. In this process, the heater 7 was not operated.

(2) Tower A: adsorption, Tower B: gas heating, adsorption tower heater: heating (25 min)
Va1, Va4, Vb3, Vb6, V8 are opened, raw material compressed air 2000 Nm ³ / h supplied from the compressor 2 is introduced from Va1 to the A tower, moisture and CO ₂ are adsorbed, and purified air is taken out from Va4. . At the same time, in order to desorb the water adsorbed in the first layer of the B tower and the CO ₂ adsorbed in the second layer, 260 Nm ³ / h of purified air heated to 150 ° C. was applied from V8, Vb6 to the B tower. While flowing, it was heated to 100 ° C. by the heater 7.

(3) Tower A: adsorption, Tower B: gas heating, adsorption tower heater: stopped (75 min)
Va1, Va4, Vb3, Vb6, V8 are opened, raw material compressed air 2000 Nm ³ / h supplied from the compressor 2 is introduced from Va1 to the A tower, moisture and CO ₂ are adsorbed, and purified air is taken out from Va4. . At the same time, in order to desorb the water adsorbed in the first layer of the B tower and the CO ₂ adsorbed in the second layer, 260 Nm ³ / h of purified air heated to 150 ° C. was applied from V8, Vb6 to the B tower. Shed The heater 7 was stopped.

(4) Tower A: adsorption, Tower B: gas cooling, adsorption tower heater: stopped (75 min)
Va1, Va4, Vb3, Vb6, V7 are opened, raw material compressed air 2000 Nm ³ / h supplied from the compressor 2 is introduced from Va1 to the A tower, water and CO ₂ are adsorbed, and purified air is taken out from Va4. . At the same time, purified air of 260 Nm ³ / h was used as a regeneration gas, and the adsorbent was cooled by flowing it from V7 and Vb6 to the B tower, and then discharged from Vb3.

(5) Tower A: adsorption, Tower B: charging, adsorption tower heater: stopped (25 min)
Va1, Va4 and Vb5 were opened, and 2000 Nm ³ / h of raw material compressed air supplied from the compressor 2 was introduced from Va1 into the A tower to adsorb moisture and CO ₂ and take out purified air from Va4. At the same time, a part of the purified air was introduced from Vb5 to charge the B tower to 400 kPa (g). In this process, the heater 7 was not operated.

After that, the A tower and the B tower were exchanged and the operation was continued.
By operating under the operating conditions shown in Test Example 1, it was possible to continuously obtain purified air from which water and CO ₂ were removed for supplying to the cryogenic separation process.
Further, in Test Example 1, the total amount of regenerated gas could be reduced by 26% as compared with the case where the TSA device 1 was operated without using the heater 7 (Comparative Example 1 described later).

<Test Example 2>
The TSA device 1 was operated in the same procedure as in Test Example 1 except that the ratio (coverage ratio) of the region where the heater 7 was provided was 10%.

(Operating conditions)
・ Adsorption towers 3A, 3B: φ1m x height 1m
・ First adsorbent: Activated alumina (300 mm)
・ Second adsorbent: Zeolite (300mm)
-Heating heater: a portion corresponding to 10% from the upper end of the first adsorbent layer 5
Wrap around (height 270-300mm position)
(Vertical length: 30 mm)
・ Heating heater replacement cycle: 0.5 years ・ Compressed air volume: 2000 Nm ³ / h
・ Compressed air pressure: 400 kPa (g)
・ Total amount of regenerated gas: 260 Nm ³ / h
・ Regeneration gas heating temperature: 150 ℃
・ Heating temperature of heater: 100 ℃
・ Cycle time: 240min
・ Adsorption: 240 min
・ Playback: 240min
・ Depressurization 10min
・ Heating 100min
(Adsorption tower heater heating 25 min)
・ Cooling 105min
・ Charging 25min

In Test Example 2, the same effect of reducing the amount of regenerated gas as in Test Example 1 was obtained.
However, since the electric power density of the heating heater 7 was increased, the life was remarkably shortened to 0.5 years, and the replacement frequency of the heating heater 7 was increased.

<Test Example 3>
The TSA device 1 was operated in the same procedure as in Test Example 1 except that the heater 7 was operated during the heating process.

(Operating conditions)
・ Adsorption towers 3A, 3B: φ1m x height 1m
・ First adsorbent: Activated alumina (300 mm)
・ Second adsorbent: Zeolite (300mm)
・ Heating heater: The portion corresponding to the upper half of the first adsorbent layer 5 (height 15
Wrap around 0-300mm position)
(Vertical length: 150 mm)
・ Heating heater replacement cycle: 5 years ・ Compressed air volume: 2000 Nm ³ / h
・ Compressed air pressure: 400 kPa (g)
・ Total amount of regenerated gas: 320 Nm ³ / h
・ Regeneration gas heating temperature: 150 ℃
・ Heating temperature of heater: 100 ℃
・ Cycle time: 240min
・ Adsorption: 240 min
・ Playback: 240min
・ Depressurization 10min
・ Heating 100min
(Adsorption tower heater heating 100 min)
・ Cooling 105min
・ Charging 25min

In Test Example 3, the total amount of regenerated gas could be reduced by 9% as compared with the case where the TSA apparatus 1 was operated without using the heater 7 (Comparative Example 1 described later).
In Test Example 3, similar to Test Example 1, the effect of reducing the regeneration gas was obtained. However, since the heater 7 was operated during the heating step, the effect of inhibiting the cooling of the adsorbent in the adsorption tower also appeared in the cooling step at the same time, so the effect of reducing the regenerated gas as in Test Example 1 was not obtained. It was

<Comparative Example 1>
The TSA device 1 was operated in the same procedure as in Test Example 1 except that the heater 7 was not used.

(Operating conditions)
・ Adsorption towers 3A, 3B: φ1m x height 1m
・ First adsorbent: Activated alumina (300 mm)
・ Second adsorbent: Zeolite (300mm)
・ Heating heater: None
・ Compressed air volume: 2000 Nm ³ / h
・ Compressed air pressure: 400 kPa (g)
・ Total amount of regenerated gas: 350 Nm ³ / h
・ Regeneration gas heating temperature: 150 ℃
・ Heating temperature of the heater:-℃
・ Cycle time: 240min
・ Adsorption: 240 min
・ Playback: 240min
・ Depressurization 10min
・ Heating 100min
(Adsorption tower heater heating 0 min)
・ Cooling 105min
・ Charging 25min

  In Comparative Example 1, since the TSA device 1 was operated without using the heater 7, the effect of reducing the amount of regenerated gas as in Test Example 1 was not obtained.

<Comparative example 2>
The TSA device 1 was operated in the same procedure as in Test Example 1 except that the heater 7 was provided on the entire side surface of the adsorption tower, under the same operating conditions as in Test Example 1.

(Operating conditions)
・ Adsorption towers 3A, 3B: φ1m x height 1m
・ First adsorbent: Activated alumina (300 mm)
・ Second adsorbent: Zeolite (300mm)
・ Heating heater: The entire side of the adsorption tower
(Vertical length: 600 mm)
・ Heating heater replacement cycle: 5 years ・ Compressed air volume: 2000 Nm ³ / h
・ Compressed air pressure: 400 kPa (g)
・ Total amount of regenerated gas: 370 Nm ³ / h
・ Regeneration gas heating temperature: 150 ℃
・ Heating temperature of heater: 100 ℃
・ Cycle time: 240min
・ Adsorption: 240 min
・ Playback: 240min
・ Depressurization 10min
・ Heating 100min
(Adsorption tower heater heating 25 min)
・ Cooling 105min
・ Charging 25min

In Comparative Example 2, as compared with Comparative Example 1, the total amount of regenerated gas increased by 5%.
In Comparative Example 2, since the heating heater 7 covered the entire side surface of the adsorption tower, the cooling of the adsorbent in the adsorption tower was hindered in the cooling step.

<Comparative example 3>
The TSA device 1 was operated in the same procedure as in Test Example 1 except that the ratio (coverage) of the region where the heater 7 was provided was 100%.

(Operating conditions)
・ Adsorption towers 3A, 3B: φ1m x height 1m
・ First adsorbent: Activated alumina (300 mm)
・ Second adsorbent: Zeolite (300mm)
-Heating heater: a portion corresponding to the entire first adsorbent layer 5
(Vertical length: 300 mm)
・ Heating heater replacement cycle: 5 years ・ Compressed air volume: 2000 Nm ³ / h
・ Compressed air pressure: 400 kPa (g)
・ Total amount of regenerated gas: 280 Nm ³ / h
・ Regeneration gas heating temperature: 150 ℃
・ Heating temperature of heater: 100 ℃
・ Cycle time: 240min
・ Adsorption: 240 min
・ Playback: 240min
・ Depressurization 10min
・ Heating 100min
(Adsorption tower heater heating 25 min)
・ Cooling 105min
・ Charging 25min

  In Comparative Example 3, by covering the side surface portion of the adsorption tower corresponding to the entire first adsorbent layer 5, the cooling of the adsorbent in the adsorption tower was hindered in the cooling step.

  DESCRIPTION OF SYMBOLS 1 ... Gas purification apparatus, 2 ... Compressor, 3A, 3B ... Adsorption tower, 4 ... Heater, 5 ... 1st adsorbent layer (adsorbent layer), 6 ... 2nd adsorbent layer (adsorbent layer), 7 ... Heating heater (heating device), L1 ... Supply line, L2 ... Depressurization line, L3 ... Exhaust gas line, L4 ... Recovery line, L5 ... Charging line, L6 ... Regeneration gas line, L7 ... Heating line, Va1 to Va6 Vb1 to Vb6, V7, V8 ... Valves

Claims (9)

A gas purification apparatus for obtaining a purified gas in which the object to be removed is removed from a raw material gas containing one or more objects to be removed by a temperature swing adsorption method,
One or more adsorption towers having a first air supply / exhaust port provided at the bottom of the tower and a second air supply / exhaust port provided at the top of the tower;
A heating device for heating the adsorption tower while covering the outer peripheral surface of the adsorption tower,
An adsorbent layer filled with an adsorbent that adsorbs at least one of the objects to be removed is provided inside the adsorption tower in a direction connecting the first air supply / exhaust port and the second air supply / exhaust port. These are stacked,
The heat energy required for the regeneration of the adsorbent corresponds to the adsorbent layer filled with the largest adsorbent, with the heating device provided only on the outer peripheral surface of the adsorption tower,
A gas purifying device, wherein a region where the heating device is not provided is provided in at least a part of the outer peripheral surface corresponding to the adsorbent layer to be heated.   A region in which the heating device is not provided is provided on a side that is a secondary side of the adsorbent layer when the adsorbent is regenerated in a direction connecting the first air supply / exhaust port and the second air supply / exhaust port. Item 1. The gas purifier according to Item 1.   The gas purifying apparatus according to claim 1, wherein the region where the heating device is not provided is provided over the entire circumferential direction of the outer peripheral surface.   Of the outer peripheral surface of the adsorption tower corresponding to the adsorbent layer to be heated, the heating device covers 15 to 50% in the direction connecting the first air supply / exhaust port and the second air supply / exhaust port. The gas purification apparatus according to claim 3, wherein the gas purification apparatus is provided.   The gas purification apparatus according to claim 1, wherein two or more of the adsorbent layers are stacked inside the adsorption tower.   6. The adsorbent layer according to claim 1, wherein the adsorbent layer having the largest thermal energy required for regeneration of the adsorbent is an adsorbent layer filled with an adsorbent that adsorbs water. Gas purifier.   The gas purification device according to claim 1, wherein the gas purification device is a pretreatment device for air separation. A gas purification method using the gas purification apparatus according to claim 1.
When regenerating the adsorbent in the adsorption tower,
After heating a part of the purified gas, introduced into the adsorption tower, a heating step of heating the adsorbent in the adsorption tower to desorb the removal object from the adsorbent,
Introduced into the adsorption tower without heating a part of the purified gas, and performing a cooling step of cooling the adsorbent heated in the heating step,
A gas purification method, wherein a heating device is operated in the heating step.   The gas purification method according to claim 8, wherein the heating device is operated only for a required time from the start of the heating step.

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