JP2009207945A - Adsorption apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the whole size of an adsorption apparatus to compose it at low cost without reducing the size of an adsorption column, while continuously adsorbing hydrogen sulfide in treating object gas. <P>SOLUTION: The adsorption apparatus is provided with the adsorption column 1 packed with an adsorbent consisting of a porous material containing ferric hydroxide for adsorbing hydrogen sulfide in the treating object gas, and a small vessel 5 for adsorbing with a smaller capacity than the adsorption column 1, and is regeneratably composed by supplying atmospheric air to the adsorption column 1. The apparatus is composed to supply the treating object gas to the small vessel 5 while regenerating the adsorbent in the adsorption column 1, and is composed to supply atmospheric air to the adsorption column 1 while stopping the supply of the treating object gas to the small vessel 5. The packing amount of the adsorbent consisting of the porous material containing ferric hydroxide packed in the small vessel 5 is set small based on the regeneration time required for regenerating the adsorbent in the adsorption column 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention, for example, removes hydrogen sulfide contained in biogas generated from a food factory or the like, or recovers a solvent contained in exhaust gas generated from a cleaning factory or the like. The present invention relates to an adsorption processing apparatus provided with an adsorption tower filled with an adsorbent that adsorbs an object to be adsorbed and configured to be able to regenerate the adsorbent in the adsorption tower.

Conventionally, the following apparatus is known as the above-described adsorption processing apparatus.
That is, a packed tower (adsorption tower) of the same size filled with activated carbon fibers is provided in parallel, and a pipe for supplying a gas to be treated is provided at one end in the longitudinal direction of both packed towers with a supply-side open / close damper. An exhaust gas pipe having a discharge side opening / closing damper is connected to the other longitudinal end of both packed towers.

In addition, a pipe for supplying steam is connected to the connection side of the exhaust gas pipes of both packed towers via a branch steam supply pipe provided with a supply-side on-off valve, and at the other end in the longitudinal direction of both packed towers. The recovery pipe is connected via a branch recovery pipe interposing a discharge side on-off valve.
A condenser, an oil / water separation tank, a distillation tower, and the like are connected to the recovery pipe.

With the above-described configuration, the gas to be treated is supplied to only one packed tower to adsorb the solvent, and the supply of the gas to be treated to the packed tower is stopped before the activated carbon fiber breaks through. The gas to be treated is supplied to the packed tower, and then steam is supplied to the packed tower that has adsorbed the solvent, the solvent adsorbed on the adsorbent is desorbed to regenerate the adsorbent and recover the desorbed solvent. However, the solvent can be continuously recovered by repeating them alternately (see Patent Document 1).
Japanese Patent Publication No. 6-7902

  In the case of the conventional publication example as described above, if the amount of adsorbent packed in the packed tower is reduced, the time until the adsorbent breaks through is shortened, and adsorption and regeneration must be repeated frequently. However, there is a problem that the damper and the on-off valve are frequently opened and closed, and the durability thereof is lowered early, and the capacity of the packed tower is increased to increase the amount of adsorbent packed.

  However, since the large-capacity packed towers are arranged side by side, there is a disadvantage that the entire apparatus is enlarged and the installation space is increased, resulting in an increase in cost.

  The present invention has been made in view of such circumstances, and it is an object of the present invention to reduce the size and size of an adsorption treatment apparatus that adsorbs hydrogen sulfide or a solvent in a gas to be treated. In the inventions according to claims 1 and 2, the adsorption tower can be continuously adsorbed to the hydrogen sulfide in the gas to be treated, but the adsorption tower is not downsized and the entire apparatus is downsized and inexpensively configured. The invention according to claim 3 aims to be able to do so, while the adsorption treatment for hydrogen sulfide in the gas to be treated can be continuously performed, but the adsorption tower is not miniaturized and the entire apparatus is further reduced in size. The invention according to claim 4 aims to avoid a decrease in the removal efficiency of hydrogen sulfide due to an unexpected decrease in the adsorption capacity of the adsorbent in the adsorption tower. Purpose to In the invention according to claim 5, while the adsorption treatment for the solvent in the gas to be treated can be continuously performed, the adsorption tower can be reduced in size and configured at low cost without downsizing the adsorption tower. Accordingly, an object of the present invention is to make it possible to avoid a decrease in solvent removal efficiency caused by an unexpected decrease in the adsorption capacity of the adsorbent in the adsorption tower.

In order to achieve the above-described object, the invention according to claim 1
An adsorption tower filled with an adsorbent made of a porous material containing ferric hydroxide is adsorbed to adsorb hydrogen sulfide in the gas to be treated, and air containing water is supplied as a regeneration gas to the adsorbent in the adsorption tower. An adsorption processing apparatus configured to perform a regeneration process,
A small vessel for adsorption treatment having a smaller capacity than the adsorption tower is provided, and the small vessel is filled with an adsorbent for a small vessel made of a porous material containing ferric hydroxide and / or ferric oxide, A pipe for supplying a gas to be treated in a state where the adsorbent in the adsorption tower is being regenerated is connected to the small container, and the filling amount of the adsorbent for the small container is set in the adsorption tower. It is characterized in that it is set to a small amount based on the regeneration time required for regenerating the adsorbent.
The regeneration time may be a time required for at least one regeneration. In this case, the amount of adsorbent for small containers is adsorbed with hydrogen sulfide in the gas to be treated for the time required for one regeneration. Anything that can be set is possible.

(Action / Effect)
According to the configuration of the adsorption processing apparatus of the invention according to claim 1, paying attention to the fact that the time required for the regeneration process is significantly shorter than the time required for the adsorption process, the adsorbent in the adsorption tower is regenerated. During the required regeneration time, hydrogen sulfide in the gas to be treated can be adsorbed on the small container adsorbent in the small container.
Therefore, when adsorbing hydrogen sulfide in the gas to be treated, the amount of the adsorbent for the small container filled in the small container can be made smaller than the amount of the adsorbent filled in the adsorption tower. However, the adsorption tower can be reduced in size and inexpensively without reducing the size of the adsorption tower, although the adsorption treatment for hydrogen sulfide in the gas to be treated can be performed continuously.
Since the adsorbent for a small container is not regenerated, unlike the adsorbent used for the adsorption tower, the adsorbent can be selected considering only the adsorption characteristics without considering the regeneration characteristics. The adsorption amount and adsorption speed of the adsorbent for the small container up to the lifetime can be selected larger than the adsorbent used in the adsorption tower, and therefore, the size can be further reduced. From this point, it is preferable to use a porous material containing ferric oxide as an adsorbent for a small container.

In order to achieve the above object, the invention according to claim 2
The adsorption processing apparatus according to claim 1,
The filling amount of the adsorbent for the small container is defined as the regeneration time required for regenerating the adsorbent in the adsorption tower and the number of times until sulfur accumulates in the adsorbent in the adsorption tower and cannot be regenerated. It is characterized by a small amount based on the processing time calculated by the product.

(Action / Effect)
According to the configuration of the adsorption processing apparatus of the invention according to claim 2, paying attention to the fact that the time required for the regeneration process is significantly shorter than the time required for the adsorption process, During the required regeneration time, hydrogen sulfide in the gas to be treated can be adsorbed on the small container adsorbent in the small container. And when using the adsorbent for small containers by the porous material containing ferric hydroxide or / and ferric oxide as the adsorbent for adsorbing hydrogen sulfide, hydrogen sulfide and ferric hydroxide or / And ferric oxide reacts to produce iron sulfide, and the iron sulfide reacts with moisture and oxygen in the air in the regeneration process to produce sulfur as ferric hydroxide, This sulfur accumulates in the porous material and becomes unrecyclable a specific number of times when it is regenerated. From the product of the number of times until the regeneration becomes impossible and the regeneration time for the adsorbent in the adsorption tower, the filling amount of the small container adsorbent and the size of the small container are set.
More specifically, for example, if the ratio of the time required for the adsorption process to the time required for the regeneration process in the adsorption tower is 42: 1, and the number of times until the regeneration in the adsorption tower becomes impossible is 14 times. The ratio between the lifetime and the time required for adsorption in the small container is 42: 14 × 1 = 3: 1, and the amount of adsorbent for small container to be packed in the small container is set in the adsorption tower. 1/3 of the life time of the adsorbent filled in can be determined as the design time.
Therefore, when adsorbing hydrogen sulfide in the gas to be treated, the amount of the adsorbent for the small container filled in the small container can be made smaller than the amount of the adsorbent filled in the adsorption tower. However, the adsorption tower can be reduced in size and inexpensively without reducing the size of the adsorption tower, although the adsorption treatment for hydrogen sulfide in the gas to be treated can be performed continuously.
As in the case of the invention according to claim 1, from the viewpoint of miniaturization, it is preferable to use a porous material containing ferric oxide as an adsorbent for a small container.

In order to achieve the above-described object, the invention according to claim 3
An adsorption tower filled with an adsorbent made of a porous material containing ferric hydroxide is adsorbed to adsorb hydrogen sulfide in the gas to be treated, and air containing water is supplied as a regeneration gas to the adsorbent in the adsorption tower. An adsorption processing apparatus configured to perform a regeneration process,
A small vessel for adsorption treatment having a smaller capacity than the adsorption tower is provided, and the small vessel is filled with an adsorbent for a small vessel made of a porous material containing ferric hydroxide and / or ferric oxide, A pipe for supplying the gas to be processed while the adsorbent in the adsorption tower is being regenerated, and a gas supply pipe for supplying the regeneration gas in a state in which the supply of the gas to be processed is stopped are described above. The small container adsorbent filling amount is set to a small amount based on the regeneration time required for regenerating the adsorbent in the adsorption tower.

(Action / Effect)
According to the configuration of the adsorption processing apparatus of the invention according to claim 3, paying attention to the fact that the time required for the regeneration process is significantly shorter than the time required for the adsorption process, During the required regeneration time, hydrogen sulfide in the gas to be treated can be adsorbed on the small container adsorbent in the small container. In addition, when an adsorbent for small containers made of a porous material containing ferric hydroxide or / and ferric oxide is used as an adsorbent for adsorbing hydrogen sulfide, hydrogen sulfide and ferric hydroxide are used in the adsorption treatment. Reacts to produce iron sulfide, and the iron sulfide reacts with moisture and oxygen in the air in the regeneration treatment to produce sulfur as it changes to ferric hydroxide, and this sulfur becomes a porous material. When it is accumulated and replayed, it becomes unplayable a specific number of times. Considering that this regeneration is impossible, the filling amount of the small container adsorbent and the size of the small container are set based on the regeneration time for the adsorbent in the adsorption tower.
More specifically, for example, when the ratio of the time required for the adsorption process and the time required for the regeneration process in the adsorption tower is 42: 1, the regeneration process is also performed on the small container adsorbent filled in the small container. In order to do so, it is proportional to the ratio of the time required for the adsorption process and the time required for the regeneration process. This means that the amount can be reduced to 1/42 of the filling amount. Actually, various effects occur because the filling amount of the adsorbent for the small container is reduced. It is possible to reduce the filling amount of the adsorbent for small containers filled in the container.
Therefore, when adsorbing hydrogen sulfide in the gas to be treated, the amount of the small container adsorbent filled in the small container is reduced in the adsorption tower compared to the case where the small container adsorbent in the small container is not regenerated. Compared to the amount of adsorbent packed in the chamber, the container can be made smaller, the hydrogen sulfide in the gas to be treated can be continuously adsorbed, but the adsorption tower is not downsized. In addition, the entire apparatus can be downsized and configured at low cost.
As in the case of the invention according to claim 1, from the viewpoint of miniaturization, it is preferable to use a porous material containing ferric oxide as an adsorbent for a small container.

In order to achieve the above-described object, the invention according to claim 4
In the adsorption processing apparatus according to any one of claims 1, 2, and 3,
The gas to be treated is configured to flow in series from the adsorption tower to the small container in a steady state where no regeneration treatment is performed on the adsorbent.

(Action / Effect)
According to the configuration of the adsorption treatment apparatus of the invention according to claim 4, hydrogen sulfide cannot be adsorbed by the adsorption tower due to an unexpected increase in the concentration of hydrogen sulfide in the gas to be treated, an unexpected delay in the regeneration treatment time, etc. Even when the adsorption capacity of the adsorbent in the adsorption tower is unexpectedly lowered, the hydrogen sulfide can be adsorbed by the adsorbent for small containers in the small container.
Therefore, it is possible to avoid a decrease in the removal efficiency of hydrogen sulfide due to an unexpected decrease in the adsorption capacity of the adsorbent in the adsorption tower.

Further, in order to achieve the above-described object, the invention according to claim 5
An adsorption processing apparatus provided with an adsorption tower filled with an adsorbent that adsorbs a solvent in a gas to be treated, and configured to perform regeneration by supplying superheated steam to the adsorbent in the adsorption tower,
A small vessel for adsorption treatment having a smaller capacity than the adsorption tower is provided, and a pipe for supplying a gas to be treated in a state in which regeneration treatment is performed on the adsorbent in the adsorption tower is connected to the small vessel. A steam branch supply pipe for supplying superheated steam in a state where supply of the gas to be treated is stopped to the small container, and the filling amount of the small container adsorbent to be filled in the small container It is characterized in that it is set to a small amount based on the regeneration time required for regenerating the adsorbent in the tower.

(Action / Effect)
According to the configuration of the adsorption processing apparatus of the invention according to claim 5, paying attention to the fact that the time required for the regeneration process is shorter than the time required for the adsorption process, the regeneration required when the adsorbent in the adsorption tower is regenerated. A small container that fills the small container based on the regeneration time for the adsorbent in the adsorption tower so that the adsorbent for the small container in the small container can adsorb the solvent in the gas to be treated during the time. Set the adsorbent filling amount and small container size.
More specifically, for example, the ratio of the time required for the adsorption process to the time required for the regeneration process in the adsorption tower is 5: 1, and the regeneration process is also performed on the small container adsorbent filled in the small container. In addition, in proportion to the ratio of the time required for the adsorption process and the time required for the regeneration process, the amount of adsorbent packed in the adsorption tower is calculated in terms of the amount of adsorbent packed in the small container. It can be made 1/5 of that.
Therefore, when adsorbing the solvent in the gas to be treated, the amount of the adsorbent for small containers filled in the small container can be made smaller than the amount of the adsorbent filled in the adsorption tower, and the small container Although it is possible to reduce the size and continuously perform the adsorption treatment on the solvent in the gas to be treated, the adsorption tower can be constructed at a low cost by downsizing the entire apparatus without downsizing.

In order to achieve the above-described object, the invention according to claim 6
The adsorption processing apparatus according to claim 5, wherein
The gas to be treated is configured to flow in series from the adsorption tower to the small container in a steady state where no regeneration treatment is performed on the adsorbent.

(Action / Effect)
According to the configuration of the adsorption treatment apparatus of the invention according to claim 6, the adsorption tower cannot be adsorbed by the adsorption tower due to an unexpected increase in the concentration of the solvent in the gas to be treated or an unexpected delay in the regeneration treatment time. Even if the adsorbing capacity of the adsorbent in the container is unexpectedly lowered, the solvent can be adsorbed by the adsorbent for the small container in the small container.
Therefore, it is possible to avoid a decrease in the solvent removal efficiency due to an unexpected decrease in the adsorption capacity of the adsorbent in the adsorption tower.

As can be seen from the above description, according to the configuration of the adsorption processing apparatus of the invention according to claim 1, paying attention to the fact that the time required for the regeneration process is significantly shorter than the time required for the adsorption process, The hydrogen sulfide in the gas to be treated can be adsorbed to the small container adsorbent in the small container during the regeneration time required for regenerating the adsorbent.
Therefore, when adsorbing hydrogen sulfide in the gas to be treated, the amount of the adsorbent for the small container filled in the small container can be made smaller than the amount of the adsorbent filled in the adsorption tower. However, the adsorption tower can be reduced in size and inexpensively without reducing the size of the adsorption tower, although the adsorption treatment for hydrogen sulfide in the gas to be treated can be performed continuously.
Since the adsorbent for a small container is not regenerated, unlike the adsorbent used for the adsorption tower, the adsorbent can be selected considering only the adsorption characteristics without considering the regeneration characteristics. The adsorption amount and adsorption speed of the adsorbent for the small container up to the lifetime can be selected larger than the adsorbent used in the adsorption tower, and therefore, the size can be further reduced. From this point, it is preferable to use a porous material containing ferric oxide as an adsorbent for a small container.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an overall schematic configuration diagram showing an embodiment 1 of an adsorption treatment apparatus according to the present invention, in which a gas to be treated having a first on-off valve V1 disposed below an adsorption tower 1 filled with an adsorbent. A supply pipe 2 is connected. A processing gas discharge pipe 3 having a second opening / closing valve V2 is connected to the upper side of the adsorption tower 1.

  A to-be-processed gas branch supply pipe 4 having a third on-off valve V3 interposed therein is connected to the upstream side of the first on-off valve V1 of the to-be-processed gas supply pipe 2. The small container 5 filled with the small container adsorbent is connected to the lower side. A processing gas branch discharge pipe 6 is connected across the upper side of the small container 5 and the downstream side of the second opening / closing valve V2 of the processing gas discharge pipe 3.

  Outside air that supplies outside air as a regeneration gas through a filter 7, a blower 8, and a fifth on-off valve V 5 at a location between the first on-off valve V 1 and the adsorption tower 1 of the gas supply pipe 2 to be treated. A supply pipe 9 is connected. In addition, an outside air discharge pipe 10 for discharging outside air after the regeneration process is connected to a portion of the processing gas discharge pipe 3 between the adsorption tower 1 and the second on-off valve V2, and a sixth gas is connected to the outside air discharge pipe 10. The on-off valve V6 is connected.

  As a regeneration gas supply pipe over a portion between the blower 8 and the fifth on-off valve V5 of the outside air supply pipe 9 and a portion between the third on-off valve V3 of the treated gas branch supply pipe 4 and the small container 5. The outside air branch supply pipe 11 is connected, and the outside air branch supply pipe 11 is connected to the seventh on-off valve V7. Further, an outside air branch discharge pipe 12 having an eighth on-off valve V8 interposed therein is connected to a portion of the processing gas branch discharge pipe 6 between the small container 5 and the fourth on-off valve V4.

Although not shown, a monitoring window for monitoring the color change of the adsorbent is provided at an upper portion of the adsorption tower 1 so that it can be determined whether the adsorbent needs to be regenerated from the color change of the adsorbent. ing.
That is, the adsorbent is formed by coating the surface of the porous material with ferric hydroxide and reacts with hydrogen sulfide as follows.
2Fe (OH) ₃ + 3H ₂ S = 2Fe ₂ S ₃ + 6H ₂ O
That is, ferric hydroxide reacts with hydrogen sulfide to generate iron sulfide, and the generated iron sulfide changes the color from orange to black, and the timing of regeneration is determined by the progress of the color change. It has become.
Regeneration is performed by passing outside air that is moisture-containing air, and is based on the following reaction.
Fe ₂ S ₃ + 3 / 2O ₂ + 3H ₂ O = 2Fe (OH) ₃ + 3S
Since sulfur is accumulated in the adsorbent as the adsorption process is repeated, the life is reached by performing regeneration a specific number of times, for example, 14 times, and requires replacement.
As a configuration for determining whether or not the adsorbent needs to be regenerated, various configurations such as sampling the gas to be processed after the adsorption process from a predetermined upper level in the adsorption tower 1 can be adopted. The same applies to Example 2, Example 3, Example 4, and Example 5 described later.

  With the above configuration, a biogas containing hydrogen sulfide generated from a food factory or the like is supplied to the adsorption tower 1 as a gas to be treated, and an adsorbing step for adsorbing hydrogen sulfide to the adsorbent, and outside air as a regeneration gas to the adsorbent The process is switched to a regeneration process that passes through, and will be described next.

Adsorption step As shown in FIG. 1A, the first and second on-off valves V1, V2 are opened, and the third, fourth, fifth, and sixth on-off valves V3, V4, V5, V6. The gas to be treated is supplied only to the adsorption tower 1, and hydrogen sulfide is adsorbed on the adsorbent. The seventh and eighth on-off valves V7 and V8 are opened only when the small container adsorbent in the small container 5 is regenerated, and the blower 8 is driven to supply the outside air only to the small container 5. After the regeneration of the small container adsorbent in the small container 5 is completed, the drive of the blower 8 is stopped and the seventh and eighth on-off valves V7 and V8 are closed.

Regeneration step After regeneration is necessary, as shown in FIG. 1B, the first and second on-off valves V1, V7, V8 are closed with the seventh and eighth on-off valves V7, V8 closed. While closing V2, the third, fourth, fifth and sixth on-off valves V3, V4, V5 and V6 are opened, the gas to be treated is supplied only to the small container 5, and the hydrogen sulfide adsorption process is continued. On the other hand, the blower 8 is driven to supply outside air only to the adsorption tower 1 to regenerate the adsorbent in the adsorption tower 1.

Next, a calculation example when the apparatus according to the first embodiment is used will be described.
As the gas to be treated, a mixture of nitrogen sulfide and hydrogen sulfide (molecular weight 34) at a concentration of 1000 ppm in the absence of moisture (temperature 25 ° C.) is used, and the flow rate is 1 m ³ N / h under the condition of the ambient temperature 25 ° C. A case was assumed in which the gas was supplied to the adsorption tower 1 at 0 ° C. and 1 atm conversion flow rate and reduced to the 1 ppm level. The regeneration air (outside air) was set to a temperature of 25 ° C. and a humidity of 60%.
The adsorption tower 1 and the small container 5 are each made of stainless steel, each filled with an adsorbent (packing density 800 kg / m ³ ) coated with ferric hydroxide on the surface of the porous material, and loaded with hydrogen sulfide Was 1.516 g / h.

The total adsorption amount of hydrogen sulfide until the end of life in the adsorption tower 1 becomes impossible to regenerate is 50% by weight, and the average amount that can be adsorbed in one adsorption process is 3.85% by weight. The number of times is 13 and the number of times that regeneration is possible, that is, the number of times until sulfur accumulates in the adsorbent in the adsorption tower 1 and becomes impossible to regenerate is 12 (13-1) times.
The time for one adsorption treatment is 300 hours, the adsorption amount in one adsorption treatment is 0.455 kg (≈1.516 g × 300 ÷ 1000), and the adsorbent filling amount in the adsorption tower 1 is 11.83 kg (≈ 0.455 ÷ 3.85 × 100), and the regeneration time required for regenerating the adsorbent in the adsorption tower 1 in the regeneration process and the small container adsorbent in the small container 5 in the adsorption process was 10 hours.

From the above configuration, the calculated filling amount of the small container adsorbent in the small container 5 specified based on the regeneration time is 0.39 kg (≈11.83 × 10 ÷ 300).
The actual filling amount of the adsorbent for the small container in the small container 5 is preferably increased from the calculated value.
This is because the influence of the adsorption zone increases due to the small packing amount, and the average value of the adsorption amount that can be adsorbed in one adsorption step is smaller than the packing value in the adsorption tower 1.
In order to reduce the influence of the adsorption zone when the amount of adsorbent is changed with the condition of the gas to be treated being fixed and the outlet concentration changes, depending on the hydrogen sulfide concentration of the gas to be treated When a certain amount of contact time (time for the gas to be processed to pass through the packed bed of the small container adsorbent) is required and the amount of the small container adsorbent filled in the small container 5 is determined, It is preferable to add an adsorbent for a small container in an amount corresponding to the contact time to the filling amount.
Further, the small container 5 filled with the adsorbent for the small container 5 multiplied by 1 to 1.5 times as a safety factor is used for the small container in the actual small container 5. The filling amount of the adsorbent may be used. In this embodiment, the contact time is assumed to be 5 seconds, and the amount of small container adsorbent added to the calculated filling amount is defined as the filling amount in the small container 5. The calculation method is shown below.
The amount of adsorbent for small containers corresponding to a contact time of 5 seconds is = 1 m ³ N / h * (298 ° C./273° C.) * (5 seconds / 3600 seconds) * 800 kg / m ³ = 1.21 kg
The amount of the small container adsorbent to be actually filled in the small container 5 is = 1.21 kg + 0.39 kg (the above-mentioned calculated filling amount) = 1.60 kg.
It becomes.
Accordingly, the capacity of the small container 5 can be set to 1 / 7.4 (≈1.60 / 11.83) of the capacity of the adsorption tower 1, and it was estimated that the size can be greatly reduced.

FIG. 2 is an overall schematic configuration diagram showing a second embodiment of the adsorption processing apparatus according to the present invention. The differences from the first embodiment are as follows.
That is, in the processing gas discharge pipe 3, the position between the connection point with the outside air discharge pipe 10 and the second on-off valve V 2, and the third on-off valve V 3 and the outside air branch supply in the processing gas branch supply pipe 4. A serially-treated gas supply pipe 21 is connected to a place between the pipe 11 and the connection place.
In the processing gas discharge pipe 3, a ninth on-off valve V <b> 9 is interposed at a position between the connection position with the outside air discharge pipe 10 and the connection position with the serial processing gas supply pipe 21. Further, in the gas branch supply pipe 4 to be processed, the tenth on-off valve V10 is interposed at a position between the connection point with the serial gas supply pipe 21 and the connection point with the outside air branch supply pipe 11. Yes. Other configurations are the same as those of the first embodiment, and the same reference numerals are given, and descriptions thereof are omitted.

  With the above-described configuration, a biogas containing hydrogen sulfide generated from a food factory or the like is supplied in series to the adsorption tower 1 and the small container 5 as a gas to be treated, and the hydrogen sulfide is adsorbed to the adsorbent and the small container adsorbent. The process can be switched between an adsorption tower regeneration process in which outside air as regeneration gas is passed through the adsorbent in the adsorption tower 1 and a small container regeneration process in which outside air as regeneration gas is passed through the adsorbent for small containers in the small container 5. This will be explained next.

Adsorption process As shown in FIG. 2A, the first, ninth, tenth and fourth on-off valves V1, V9, V10, V4 are opened, and the second, third, fifth, sixth are opened. The seventh and eighth on-off valves V2, V3, V5, V6, V7, and V8 are closed, and the gas to be treated is supplied in series from the adsorption tower 1 to the small vessel 5 to sulfidize the adsorbent and the small vessel adsorbent. Adsorb hydrogen.
According to this configuration, even if hydrogen sulfide is not adsorbed to the adsorbent in the adsorption tower 1 unexpectedly, the hydrogen sulfide flowing through the adsorption tower 1 can be adsorbed by the small container adsorbent in the small container 5.

Adsorption tower regeneration step After regeneration of the adsorbent in the adsorption tower 1 is required, as shown in FIG. 2B, the third, tenth, fourth, fifth and sixth on-off valves V3, V10, V4, V5 and V6 are opened, the first, ninth, second, seventh and eighth V1, V9, V2, V7 and V8 are closed, and the gas to be treated is supplied only to the small container 5. Then, while continuing the adsorption treatment of hydrogen sulfide, the blower 8 is driven to supply the outside air only to the adsorption tower 1 to regenerate the adsorbent in the adsorption tower 1.

Small container regeneration step After the regeneration of the adsorbent in the adsorption tower 1 is completed, as shown in FIG. 2 (c), the first, ninth, second, seventh and eighth V1, V9, V2, V7, V8 are opened, the third, tenth, fourth, fifth and sixth on-off valves V3, V10, V4, V5, V6 are closed, and the gas to be treated is supplied only to the adsorption tower 1, While the hydrogen sulfide is being adsorbed, the blower 8 is driven to supply outside air only to the small container 5, and the small container adsorbent in the small container 5 is regenerated. After the regeneration for the small container adsorbent in the small container 5 is completed, the process returns to the adsorption step of supplying the gas to be treated to the adsorption tower 1 and the small container 5 in series.

FIG. 3 is an overall schematic configuration diagram showing the third embodiment of the adsorption processing apparatus according to the present invention. The differences from the first embodiment are as follows.
That is, in the first embodiment, the outside air branch supply pipe 11, the seventh on-off valve V7, the outside air branch discharge pipe 12 and the eighth on-off valve V8 are eliminated, and the regeneration process for the small container adsorbent in the small container 5 is performed. Is configured to not. Other configurations are the same as those of the first embodiment, and the same reference numerals are given, and descriptions thereof are omitted.

  With the above configuration, a biogas containing hydrogen sulfide generated from a food factory or the like is supplied to the adsorption tower 1 as a gas to be treated, and an adsorbing step for adsorbing hydrogen sulfide to the adsorbent, and outside air as a regeneration gas to the adsorbent The process is switched to a regeneration process that passes through, and will be described next.

Adsorption process As shown in FIG. 3A, the first and second on-off valves V1, V2 are opened, and the third, fourth, fifth, and sixth on-off valves V3, V4, V5, V6. The gas to be treated is supplied only to the adsorption tower 1, and hydrogen sulfide is adsorbed on the adsorbent.
-Regeneration process After regeneration is required, the first and second on-off valves V1, V2 are closed and the third, fourth, fifth, and sixth are closed as shown in FIG. The on-off valves V3, V4, V5, and V6 are opened, the gas to be treated is supplied only to the small container 5, and the hydrogen sulfide adsorption process is continued. On the other hand, the blower 8 is driven to supply outside air only to the adsorption tower 1 to regenerate the adsorbent in the adsorption tower 1.

Next, a calculation example when the apparatus according to the third embodiment is used will be described.
As the gas to be treated, a mixture of nitrogen sulfide and hydrogen sulfide (molecular weight 34) at a concentration of 500 ppm in the absence of moisture (temperature 25 ° C.) is used, and the flow rate is 1 m ³ N / h under the condition of the atmospheric temperature 25 ° C. A case was assumed in which the gas was supplied to the adsorption tower 1 at 0 ° C. and 1 atm conversion flow rate and reduced to the 1 ppm level. The regeneration air (outside air) was set to a temperature of 25 ° C. and a humidity of 60%.
The adsorption tower 1 and the small container 5 are each made of stainless steel and filled with an adsorbent in which the surface of the porous material is coated with ferric hydroxide, and the load of hydrogen sulfide is 0.757 g / h. It was.

The total adsorption amount of hydrogen sulfide until the end of life in the adsorption tower 1 becomes impossible to regenerate is 50% by weight, and the average amount that can be adsorbed in one adsorption step is 3.85% by weight. The number of times is 13, and the number of times that regeneration is possible, that is, the number of times until sulfur accumulates in the adsorbent in the adsorption tower 1 and becomes impossible to regenerate is 12 (13-1) times.
The time for one adsorption treatment is 500 h, the adsorption amount in one adsorption treatment is 0.379 kg (≈0.757 g × 500 ÷ 1000), and the adsorbent filling amount in the adsorption tower 1 is 9.85 kg (≈ 0.379 ÷ 3.85 × 100), and the regeneration time required for regenerating the adsorbent in the adsorption tower 1 in the regeneration process was 10 hours.

From the above configuration, the calculation filling of the adsorbent for the small container in the small container 5 set based on the processing time (12 × 10 h) calculated from the product of the regeneration time and the number of times until the regeneration becomes impossible. The amount is 2.36 kg (≈9.85 × 12 × 10 ÷ 500).
In Example 3, the contact time for reducing the influence of the adsorption band was 4 seconds. 0.97 kg of the small container adsorbent corresponding to this contact time was added to the calculated filling amount, so that the actual filling amount into the small container 5 was 3.33 kg (= 2.36 kg + 0.97 kg).
Accordingly, the capacity of the small container 5 can be set to 1 / 3.0 (≈3.33 / 9.85) of the capacity of the adsorption tower 1, and it is estimated that the size can be greatly reduced.

FIG. 4 is an overall schematic configuration diagram illustrating an adsorption processing apparatus according to a fourth embodiment of the present invention. The differences from the second embodiment are as follows.
That is, in the second embodiment, the outside air branch supply pipe 11, the seventh on-off valve V7, the outside air branch discharge pipe 12 and the eighth on-off valve V8 are eliminated, and the regeneration process for the small container adsorbent in the small container 5 is performed. Is configured to not. Other configurations are the same as those of the second embodiment, and the same reference numerals are given and description thereof is omitted.

  With the above configuration, an adsorption step of supplying biosulfur containing hydrogen sulfide generated from a food factory or the like to the adsorption tower 1 as a gas to be treated, and adsorbing hydrogen sulfide to the adsorbent and the adsorbent for small containers, and the adsorbent Switching to a regeneration process through which outside air as regeneration gas is passed will be described next.

Adsorption process As shown in FIG. 4A, the first, ninth, tenth and fourth on-off valves V1, V9, V10, V4 are opened and the second, third, fifth and sixth are opened. The on-off valves V2, V3, V5, and V6 are closed, and the gas to be treated is supplied in series from the adsorption tower 1 to the small container 5 to adsorb hydrogen sulfide on the adsorbent and the small container adsorbent.
According to this configuration, even if hydrogen sulfide is not adsorbed to the adsorbent in the adsorption tower 1 unexpectedly, the hydrogen sulfide flowing through the adsorption tower 1 can be adsorbed by the small container adsorbent in the small container 5.

-Regeneration process After regeneration of the adsorbent in the adsorption tower 1 becomes necessary, as shown in FIG. 4B, the third, tenth, fourth, fifth and sixth on-off valves V3, V10, V4, V5, and V6 are opened, the first, ninth, and second on-off valves V1, V9, and V2 are closed, the gas to be processed is supplied only to the small container 5, and the hydrogen sulfide adsorption process is continued. However, the blower 8 is driven to supply outside air only to the adsorption tower 1 to regenerate the adsorbent in the adsorption tower 1.

In Example 5 of the adsorption processing apparatus according to the present invention, the small container 5 was filled with an adsorbent made of a porous material containing ferric oxide as an adsorbent for the small container.
The reaction formula of ferric oxide and hydrogen sulfide is as follows.
Fe ₂ O ₃ + 3H ₂ S = Fe ₂ S ₃ + 3H ₂ O
That is, ferric oxide reacts with hydrogen sulfide to produce iron sulfide. Other configurations are the same as those of the third embodiment.

Next, a calculation example of the fifth embodiment will be shown.
The gas to be treated is a biogas obtained from a biogas plant, the average concentration of hydrogen sulfide (molecular weight 34) in the biogas is 1500 ppm, and the flow rate of the gas to be treated is 6 liter / h (25 ° C., 1 Pressure converted to atmospheric pressure). The load of hydrogen sulfide under this condition is 0.0125 g / h.

The adsorption tower 1 is made of stainless steel, and the adsorption tower 1 is filled with 188 g of a granular adsorbent (Sulfur Bind: manufactured by Sanix) made of a porous material containing ferric hydroxide. The amount of adsorption that can be adsorbed in one adsorption process of this adsorbent is 3.3% by weight, and the number of times of regeneration after one adsorption process is 14, that is, the number of adsorption processes that can be performed is 15 times. The cumulative amount of adsorption of hydrogen sulfide until the end of its life cannot be regenerated is about 50% by weight (≈3.3% by weight × 15). The time required for reproduction is 10 hours.
The time of one adsorption treatment under the above conditions (the time for the adsorption amount to be 3.3% by weight) is 496 h (≈ [188 × 0.033] ÷ 0.0125).

The small container 5 is also made of stainless steel, and the small container 5 is filled with a commercially-available adsorbent for a small container made of a porous material containing ferric oxide and having an adsorption amount of about 20% by weight until the end of its life. To do. This is much larger than the adsorption amount of the adsorbent of the adsorption tower 1 of 3.3% by weight. However, it is smaller than the integrated adsorption amount (about 50% by weight) of the adsorbent in the adsorption tower 1. The shape of the adsorbent for a small container was a cylindrical pellet having a diameter of 10 mm, and an averaged length of about 6 mm was used.
The life required of the small container 5 filled with the small container adsorbent is determined based on the performance of the adsorbent filled in the adsorption tower 1. That is, the processing time 140h [(15-1) × 10h] calculated from the product of the reproduction time and the number of times until reproduction becomes impossible corresponds to this.
The filling amount of the small container adsorbent in the small container 5 that satisfies the treatment time was found to be about 69.74 g by the following experiment. From this result, the ratio of the filling amount of the adsorbent for the small container and the filling amount of the adsorbent in the adsorption tower 1 is 69.74: 188, which can be reduced to about 1/2. It became clear that it would be possible.

<Experiment to determine the filling amount of adsorbent for small containers>
An experiment for determining the filling amount of the adsorbent for a small container was performed as follows.
As the gas to be treated for the experiment, a simulated biogas was used for easy testing. The composition ratio of methane and carbon dioxide in the simulated biogas was in a general range of 70% by volume of methane and 30% by volume of carbon dioxide, and the hydrogen sulfide concentration was 1500 ppm, the same as above. The flow rate and temperature of the gas to be treated were also set to 6 liter / h (25 ° C., 1 atm equivalent flow rate) as described above.
For 3 levels of adsorbents 50g, 60g and 70g for small containers in the small container 5, the gas to be treated for the experiment is processed, and the breakthrough time (until the outlet concentration of the small container 5 rises to about 20ppm) Time). The results were 71h, 102h, and 141h, respectively, and the filling amount necessary to obtain the above-mentioned life 140h was approximately 69,74 g [-≈60 + 10 × 38/39] from proportional calculation.
The adsorbent for small containers made of the porous material containing ferric oxide described above may be used in the adsorption processing apparatus of Example 4 above.

As the adsorbent for small containers made of a porous material containing ferric oxide used in Example 5, the powders of ferric oxide, calcium oxide, and silica sand are mixed and extruded into a pellet shape. Alternatively, a powder obtained by mixing ferric oxide powder and clay and extruding into a pellet may be used. In addition, a naturally produced ocher may be extruded into a pellet.
The present invention is based on the porous material containing the mixture of ferric hydroxide and ferric oxide in the small container 5 in the above-mentioned Example 1, Example 2, Example 3, Example 4 and Example 5. It may be filled with an adsorbent for a small container.

FIG. 5 is an overall schematic configuration diagram showing the sixth embodiment of the adsorption processing apparatus according to the present invention. The differences from the first embodiment are as follows.
Adsorbing and recovering the solvent from the gas to be treated containing the solvent, the adsorbent filled in the adsorption tower 1 and the adsorbent for the small container filled in the small container 5 are granular activated carbon for solvent recovery, A configuration in which superheated steam for regeneration is supplied instead of the filter 7, the blower 8, the fifth, sixth, seventh and eighth on-off valves V5, V6, V7, V8, the outside air supply pipe 9 and the outside air branch discharge pipe 12. Is provided.

  That is, a steam supply pipe 31 for supplying superheated steam is connected to a portion of the processing gas discharge pipe 3 between the adsorption tower 1 and the second on-off valve V2, and the eleventh on-off valve V11 is connected to the steam supply pipe 31. Is connected. In addition, the twelfth on-off valve V12 extends over a location upstream of the eleventh on-off valve V11 of the steam supply pipe 31 and a portion between the small container 5 and the fourth on-off valve V4 of the processing gas discharge pipe 6. A steam branch supply pipe 32 is connected as a regeneration gas supply pipe interposed.

  A solvent recovery pipe 33 having a thirteenth on-off valve V13 interposed is connected to a portion of the gas supply pipe 2 between the first on-off valve V1 and the adsorption tower 1, and a condenser 34 is connected to the solvent recovery pipe 33. And a solvent recovery tank 35 are connected in that order. Further, the solvent branch extends over a portion between the thirteenth on-off valve V13 of the solvent recovery pipe 33 and the condenser 34 and a portion between the third on-off valve V3 of the treated gas branch supply pipe 4 and the small container 5. A recovery pipe 36 is connected, and a fourteenth on-off valve V14 is connected to the solvent branch recovery pipe 36. The solvent recovery tank 35 is provided with a diffusion port 37 for uncondensed gas generated at the initial stage of the regeneration process. Other configurations are the same as those of the first embodiment, and the same reference numerals are given, and descriptions thereof are omitted.

  With the above configuration, a gas containing a solvent generated from a cleaning factory or the like is supplied to the adsorption tower 1 as a gas to be treated, an adsorption process for adsorbing the solvent to the adsorbent, and superheated steam as a regeneration gas is supplied to the adsorbent. Thus, the process can be switched to a regeneration process for desorbing the solvent.

Adsorption process As shown in FIG. 5A, the first and second on-off valves V1, V2 are opened, and the third, fourth, eleventh and thirteenth on-off valves V3, V4, V11, V13 are opened. The gas to be treated is supplied only to the adsorption tower 1, and the adsorbent is made to adsorb the solvent. The twelfth and fourteenth on-off valves V12 and V14 are opened only when the adsorbent for the small container in the small container 5 is regenerated, and superheated steam is supplied only to the small container 5. After the regeneration for the small container adsorbent in the small container 5 is completed, the twelfth and fourteenth on-off valves V12 and V14 are closed.

Regeneration step After regeneration is necessary, as shown in FIG. 5B, the first and second on-off valves V1, V1 and V14 are closed with the twelfth and fourteenth on-off valves V12 and V14 closed. While V2 is closed, the third, fourth, eleventh and thirteenth on-off valves V3, V4, V11, V13 are opened, the gas to be treated is supplied only to the small container 5, and the solvent adsorption process is continued. On the other hand, superheated steam is supplied only to the adsorption tower 1 to regenerate the adsorbent in the adsorption tower 1.

Next, an example of calculation when the apparatus according to the sixth embodiment is used will be described.
The gas to be treated is assumed to be a mixture of nitrogen gas and octamethylcyclotetrasiloxane (molecular weight 297) at a concentration of 20 ppm in the absence of moisture (temperature 25 ° C.). ³ N / h (0 ° C., 1 atm equivalent flow rate) is supplied to the adsorption tower 1, and the time average concentration of octamethylcyclotetrasiloxane at the outlet of the adsorption tower 1 and the small vessel 5 is about 0.5 ppm (removal rate is 97 .5%) was assumed. As the regeneration air (superheated steam), one having a temperature of 220 ° C. was supplied at a flow rate of 0.06 kg / h.
The adsorption tower 1 and the small container 5 were each made of stainless steel and assumed to be filled with granular activated carbon at a packing density of 410 kg / m ³ . The filling amount of the adsorbent into the adsorption tower 1 was 0.25 kg, and the filling amount of the small vessel adsorbent into the small container 5 was 0.05 kg.

In the adsorption process, the gas to be treated was allowed to flow to the adsorption tower 1 continuously for 48 hours, and the treatment gas was diffused into the atmosphere. After adsorption for 48 hours in the adsorption process, the process shifted to the regeneration process, and superheated steam was passed through the adsorption tower 1 for 2 hours. The desorbed octamethylcyclotetrasiloxane is cooled together with water vapor by a condenser 34 and collected in a solvent recovery tank 35 as a liquid. Thereafter, the supply of superheated water vapor is stopped and outside air is supplied for 30 minutes to cool the adsorbent to room temperature. Then, the regeneration step of the adsorption tower 1 is completed.
For the small container 5, the gas to be treated is supplied for a time during which the adsorption tower 1 is in the regeneration process, and the octamethylcyclotetrasiloxane is adsorbed on the small container adsorbent in the small container 5. The regeneration time was 1 hour, and after the regeneration, it was left to cool naturally.

  As for the capacity of the small container 5, the regeneration time required for regenerating the adsorbent in the adsorption tower 1 in the regeneration step is 2.5 hours including the cooling time. From the comparison with the continuous adsorption time (48 hours), the filling amount of the adsorbent for the small container can be reduced to 1 / 19.2 (2.5 / 48) of the adsorbent of the adsorption tower 1. In consideration of various effects resulting from the decrease in the filling amount, the value was set to 1/5 based on the regeneration time.

  In Example 6 above, as the adsorbent and the adsorbent for the small container, fibrous activated carbon, or both granular activated carbon and fibrous activated carbon may be used.

  The adsorption treatment apparatus of Example 1, Example 2, Example 3, Example 4 and Example 5 is from a biogas plant using anaerobic digester, biogas generated from sewage, livestock, and industrial waste. Treatment of hydrogen sulfide contained in biogas such as biogas-producing urine treatment plant, final disposal site where anaerobic gas is generated from landfill waste, and urban sewage treatment plant where biogas is generated from digestion tank It can be applied to various cases, for example, when processing hydrogen sulfide generated from dead cattle at a BSE countermeasure plant.

  The present invention pays attention to the fact that the regeneration time is significantly shorter than the adsorption treatment time in the adsorption tower 1, and in the case where the small container adsorbent filled in the small container 5 is not regenerated, The adsorbing tower is not limited to the one in which the packed amount is set to an amount sufficient to adsorb hydrogen sulfide for the time required for the adsorption tower 1 to reach the end of its life. It may be set to an amount sufficient to adsorb hydrogen sulfide for a shorter time than 1 reaches the life.

It is a whole schematic block diagram which shows Example 1 of the adsorption processing apparatus which concerns on this invention. It is a whole schematic block diagram which shows Example 2 of the adsorption processing apparatus which concerns on this invention. It is a whole schematic block diagram which shows Example 3 of the adsorption processing apparatus which concerns on this invention. It is a whole schematic block diagram which shows Example 4 of the adsorption processing apparatus which concerns on this invention. It is a whole schematic block diagram which shows Example 6 of the adsorption processing apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Adsorption tower 2 ... Process gas supply pipe 4 ... Process gas branch supply pipe (pipe)
5 ... Small container 9 ... Outside air supply pipe 11 ... Outside air branch supply pipe (regenerative gas supply pipe)
21 ... Process gas supply pipe for series 31 ... Steam supply pipe 32 ... Steam branch supply pipe (regeneration gas supply pipe)

Claims (6)

An adsorption tower filled with an adsorbent made of a porous material containing ferric hydroxide is adsorbed to adsorb hydrogen sulfide in the gas to be treated, and air containing water is supplied as a regeneration gas to the adsorbent in the adsorption tower. An adsorption processing apparatus configured to perform a regeneration process,
A small vessel for adsorption treatment having a smaller capacity than the adsorption tower is provided, and the small vessel is filled with an adsorbent for a small vessel made of a porous material containing ferric hydroxide and / or ferric oxide, A pipe for supplying a gas to be treated in a state where the adsorbent in the adsorption tower is being regenerated is connected to the small container, and the filling amount of the adsorbent for the small container is set in the adsorption tower. An adsorption processing apparatus characterized in that the adsorbent is set to a small amount based on a regeneration time required for regenerating the adsorbent. The adsorption processing apparatus according to claim 1,
The filling amount of the adsorbent for the small container is defined as the regeneration time required for regenerating the adsorbent in the adsorption tower and the number of times until sulfur accumulates in the adsorbent in the adsorption tower and cannot be regenerated. An adsorption processing apparatus characterized in that a small amount is set based on a processing time calculated by a product. An adsorption tower filled with an adsorbent made of a porous material containing ferric hydroxide is adsorbed to adsorb hydrogen sulfide in the gas to be treated, and air containing water is supplied as a regeneration gas to the adsorbent in the adsorption tower. An adsorption processing apparatus configured to perform a regeneration process,
A small vessel for adsorption treatment having a smaller capacity than the adsorption tower is provided, and the small vessel is filled with an adsorbent for a small vessel made of a porous material containing ferric hydroxide and / or ferric oxide, A pipe for supplying the gas to be processed while the adsorbent in the adsorption tower is being regenerated, and a gas supply pipe for supplying the regeneration gas in a state in which the supply of the gas to be processed is stopped are described above. An adsorption processing apparatus, wherein the adsorption processing apparatus is connected to a container and the filling amount of the adsorbent for the small container is set to a small amount based on a regeneration time required for regenerating the adsorbent in the adsorption tower. In the adsorption processing apparatus according to any one of claims 1, 2, and 3,
An adsorption treatment apparatus configured to flow a gas to be treated in series from an adsorption tower to a small container in a steady state where no regeneration treatment is performed on the adsorbent. An adsorption processing apparatus provided with an adsorption tower filled with an adsorbent that adsorbs a solvent in a gas to be treated, and configured to perform regeneration by supplying superheated steam to the adsorbent in the adsorption tower,
A small vessel for adsorption treatment having a smaller capacity than the adsorption tower is provided, and a pipe for supplying a gas to be treated in a state in which regeneration treatment is performed on the adsorbent in the adsorption tower is connected to the small vessel. A steam branch supply pipe for supplying superheated steam in a state where supply of the gas to be treated is stopped to the small container, and the filling amount of the small container adsorbent to be filled in the small container An adsorption processing apparatus characterized in that a small amount is set based on a regeneration time required when the adsorbent in the tower is regenerated. The adsorption processing apparatus according to claim 5, wherein
An adsorption treatment apparatus configured to flow a gas to be treated in series from an adsorption tower to a small container in a steady state where no regeneration treatment is performed on the adsorbent.

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