JPH03288515A - Rotary type gas treatment apparatus - Google Patents

Abstract

PURPOSE:To eliminate the accumulation of a hardly desorbable substance on a rotary body by making the average pore size of the constitutional fine activated carbon of the pre-stage rotary body positioned on the upstream side in the duct of gas to be treated larger than that of the constitutional fine activated carbon of the post-stage rotary body on the downstream side. CONSTITUTION:A plurality of rotary bodies 1, 2 composed of fine activated carbon being a main constitutional material and permeable to gas in the direction of the rotary axis P thereof are provided. Adsorbing regions A1, A2 permitting gas G to be treated to pass and desorbing regions B1, B2 permitting regeneration gas H to pass are provided in the rotary regions of the rotary bodies 1, 2. The adsorbing regions A1, A2 are arranged to a series of the gas ducts GF of the gas to be treated in the duct direction thereof and the desorbing regions B1, B2 are arranged to regeneration gas ducts HF1, HF2. The average pore size of the constitutional fine activated carbon of the predetermined stage rotary body 1 positioned on the upstream side in the gas ducts GF of the gas to be treated is made larger than that of the constitutional fine activated carbon of the post-stage rotary body 2 positioned on the downstream side. As a result, a hardly desorbable substance is not accumulated on the rotary bodies and properly removed from the gas to be treated.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a plurality of rotating bodies that are mainly composed of fine activated carbon and that can be ventilated in the direction of the axis of rotation, and the rotation range of each of the rotating bodies is an adsorption region through which the waste to be treated passes and a desorption region through which the regeneration gas passes; the adsorption regions of each of the rotating bodies are arranged in a series of to-be-treated gas air paths in the direction of the air paths; The desorption area on the surface of the rotating body is arranged in the regeneration gas air path, so that the gas to be treated can be continuously processed by repeating adsorption and desorption by rotation across the adsorption area and the desorption area on the surface of the rotating body. The present invention relates to a rotary gas treatment device.

[Conventional technology]

Conventionally, in the above-mentioned rotary gas treatment apparatus, fine activated carbon constituting the surfaces of a plurality of rotating bodies has been used that has the same average pore diameter.

[Problem to be solved by the invention]

However, if the molecular diameter of the adsorbed substance in the gas to be treated (for example, the solvent contained in the exhaust gas of a paint booth) is average, and the average pore diameter of the constituent fine activated carbon matches that average molecular diameter, then Even with the conventional configuration described above, adsorption and desorption are performed appropriately in each of the rotating bodies. Desorbable substances that easily become large in diameter and are not easily desorbed after adsorption because they have too strong an affinity for activated carbon or become physically trapped in the pores (e.g., high-boiling solvents) In the case of a gas to be treated that contains even a small amount of adsorbed substances (polymerizable substances, polymerizable substances, etc.) with the above-mentioned average molecular diameter, the desorption-adsorbable substances are not desorbed in the desorption area and accumulate on the rotating body after being adsorbed in the adsorption area. As a result, the efficiency of adsorption and desorption is reduced and the life of the rotating body is significantly shortened, which also poses the problem of increased maintenance costs.

An object of the present invention is to solve the above-mentioned problems by rationally configuring a plurality of rotating bodies in which each adsorption region is arranged in a series of gas channels to be treated in the direction of the channels.

[Means to solve the problem]

The first characteristic configuration of the rotary gas treatment apparatus according to the present invention is as follows:
A plurality of rotating bodies whose main constituent material is fine activated carbon and which can be ventilated in the direction of the rotation axis are provided, and an adsorption area through which the gas to be treated passes and a regenerating gas pass through the rotation area on the surface of the rotating bodies. a desorption area, and the adsorption area on the surface of the rotating body is arranged in a series of gas air passages in the direction of the air passage,
In the configuration in which the desorption area on the surface of the rotating body is arranged in the regeneration gas air path, the fine activated carbon constituting the pre-stage rotating body located on the upstream side in the to-be-treated gas air path of the rotating body is located on the downstream side. The second stage rotating body is made to have a larger average pore diameter than the fine activated carbon, and its functions and effects are as follows.

[For production]

In other words, even if the fine activated carbon constituting the first-stage rotor is adsorbed in the adsorption region, even if the molecular diameter is larger than the average molecular diameter of the adsorbed substance, or if the molecular diameter has increased due to alteration, etc., the fine activated carbon can be adsorbed. The average pore diameter is relatively large so that it can be easily desorbed in the desorption zone, and this allows the front-stage rotating body to desorb a relatively small amount of the gas contained in the gas to be treated together with the adsorbed substance having the above-mentioned average molecular diameter. With a dedicated rotating body for adhering substances, adsorption and desorption in the first stage rotary body properly removes the detachable substances from the gas to be treated without accumulating them on the rotating body, and the adsorption and desorption substances are removed from the gas to be removed and attached to the second stage rotary body. Prevent the outflow of sexual homogeneity.

On the other hand, by making the fine activated carbon that constitutes the pre-stage rotor to have a relatively large average pore diameter suitable for the detachable and adsorbable substances, the adsorption and removal efficiency of the pre-stage rotor for adsorbed substances with the above-mentioned average molecular diameter decreases. Alternatively, the fine activated carbon constituting the latter rotating body can be adjusted to match the average molecular size of the adsorbed substance (i.e.,
By making the average pore diameter relatively small, the gap between the pore and the adsorbed substance that enters the pore is relatively small, and the adsorption effect is high. By desorption, adsorbed substances with an average molecular size are efficiently removed from the gas to be treated.

In this latter-stage rotary body, since the separable and adsorbable substances have already been removed from the gas to be treated by adsorption and desorption in the upstream front-stage rotary body, accumulation of the separable and adsorbable substances is avoided.
Furthermore, since the difficult-to-desorb substances do not become an obstacle in adsorbing substances with an average molecular diameter, the separation and collection efficiency for adsorbed substances with an average molecular diameter is improved.

〔Effect of the invention〕

As a result of the above, according to the first characteristic configuration of the present invention, a relatively small amount of desorbable substances contained in the gas to be treated together with the adsorbed substance having an average molecular diameter are not desorbed after being adsorbed and are not desorbed at each rotation. Accumulation on the body can be effectively avoided, the lifespan of each rotating body can be extended compared to the conventional one, and maintenance costs can thereby be reduced to a large extent.

Moreover, the separable and adsorbable substances contained in the gas to be treated, which conventionally were only accumulated on the rotating body but could not be properly separated and collected, can be continuously and appropriately separated and collected by adsorption and desorption by the rotation of the preceding rotating body. This also makes it possible to maintain a high separation and collection efficiency of the downstream rotor for adsorbed substances with an average molecular diameter, thereby improving the processing performance and versatility of this type of rotary gas treatment equipment. I was able to improve it.

[Second to fourth characteristic configurations of the present invention] The second characteristic configuration of the rotary gas treatment apparatus according to the present invention is as follows:
The average pore diameter of the fine activated carbon constituting the first-stage rotary body is 1.
It is more than 1 times and less than 35A.If this second characteristic configuration is adopted, experimental results show that paint solvent is included as an adsorbed substance with an average molecular diameter, and compared as a detachable and adsorbable substance. In the treatment of exhaust gas from a paint booth that contains a small amount of high-boiling point solvent, ketones that undergo oxidative decomposition and deterioration in quality, polymerizable substances, etc., the effect of the above-mentioned first characteristic configuration can be brought out significantly.

Specifically, in the treatment of exhaust gas from a paint booth, in order to efficiently adsorb and desorb the adsorbed substances with the above-mentioned average molecular diameter, the average pore diameter of the fine activated carbon constituting the latter rotating body must be 1.
It is desirable that the number of people be within the range of about 4 people to 23λ.

This is because if the average pore diameter is too small, the affinity between the activated carbon and the adsorbed substance will be strong and the desorption performance will be reduced, and if the average pore diameter is too large, the affinity between the activated carbon and the adsorbed substance will be weakened. This is due to reasons such as a decrease in adsorption properties, and both of these cases cause a decrease in processing performance.

Furthermore, if the average pore diameter of the fine activated carbon constituting the first-stage rotary body is 1.1 times or more the average pore diameter of the fine activated carbon constituting the second-stage rotary body, the desorption performance of the detachable substance in the first-stage rotary body will be lower than that of the second-stage rotary body. Significant improvement compared to rotating bodies.

However, if the average pore diameter of the pre-stage rotor is larger than 35 pores, the specific surface area of activated carbon will be small due to the nature of activated carbon, resulting in a decrease in adsorption capacity and further a decrease in adsorption efficiency for the above-mentioned detachable substances. It may happen.

Here, the average pore diameter refers to a value used in boat fishing, for example, a value calculated from the specific surface area and pore volume determined by the B, E, T method using N2 gas.

In addition, in the case of a molded body such as a cam structure made of the fine activated carbon and other substances, the average pore diameter of the molded body obtained by measuring the specific surface area and pore volume of the molded body is the same as that of the molded body. The average pore diameter value of the fine activated carbon used in

A third characteristic configuration of the rotary gas treatment apparatus of the present invention resides in that the rotational speed of the first stage rotary body is made smaller than the rotational speed of the second stage rotary body, and if this third characteristic configuration is adopted, By making the adsorption time in the adsorption zone and the desorption time in the desorption zone of the front-stage rotor longer than those of the rear-stage rotor, the amount of the adsorbed substance is smaller than that of the average molecular diameter, and the adsorption efficiency is low. In addition, it is possible to improve the adsorption and desorption efficiency of the front-stage rotor for detachable substances that inherently have low desorption efficiency, and as a result, the average pore diameter of the fine activated carbon that constitutes the front-stage rotor is relatively smaller than that of the rear-stage rotor. Coupled with the effect of the first characteristic configuration that makes the particle size larger, it is possible to further improve the desorption efficiency of the pre-stage rotating body for the desorbable substances partially contained in the gas to be treated together with the adsorbed substance having an average molecular diameter. .

A fourth characteristic configuration of the rotary gas treatment apparatus according to the present invention is as follows:
The first stage rotating body is made to have a thickness smaller in the direction of the axis of rotation than the second stage rotating body, and detachment and adhesion substances such as high boiling point solvents can be easily adsorbed and the adsorption zone can be short. If the amount of the detachable and adsorbable substance is small compared to the adsorbed substance of average molecular size, the thickness of the rotating body can be made smaller because it will not become saturated in the rotating body even if the thickness of the preceding stage rotating body is small. Based on the above, this fourth
By adopting this characteristic configuration, it is possible to reduce the temperature drop of the regeneration gas from the regeneration gas inlet to the outlet in the desorption zone of the front-stage rotor compared to that of the rear-stage rotor, and to reduce the temperature drop of the regeneration gas from the regeneration gas inlet to the outlet in the desorption zone of the front-stage rotor. The desorption of the detachable substance, which is inherently difficult to desorb compared to the substance, at the front rotor can be promoted by maintaining the high temperature of the regeneration gas by shrinking during the temperature drop as described above,
As a result, in conjunction with the effect of the first characteristic configuration described above, and also in conjunction with the effect of the third characteristic configuration when the third characteristic configuration described above is adopted, the separable adhesion substance in the preceding stage rotating body is desorption efficiency can be further improved.

In addition, by reducing the thickness of the front-stage rotor in the direction of the rotational axis, that is, in the direction in which the gas to be treated and the regeneration gas pass, the pressure loss in the air path for the gas to be treated and the regeneration gas can be reduced for the entire device. Therefore, fan power can be saved.

〔Example〕

Figures 1 and 2 show a rotary gas treatment device that uses exhaust gas from a painting booth as a gas to be treated, and separates and collects paint solvents, etc. contained in this exhaust gas to purify the exhaust gas as a gas to be treated. /S with fibrous fine activated carbon as the main constituent material
It consists of two disc-shaped rotating bodies (1) and (2) that have a nicum structure and can ventilate in the direction of the rotational axis (P), and these rotating bodies (1)
) and (2) are arranged concentrically within the casing (3) at appropriate intervals.

The casing (3) allows the gas to be treated (G) to flow in from the - end in the direction in which the rotating bodies are arranged side by side (i.e., in the direction of the rotation axes (P) of the rotating bodies (1) and (2)). Gas (G
) for both rotating bodies (1), (2) the same specific phase portion (A1) in each rotation range, (A2) for both rotating bodies (1).
), (2), a series of gas flow paths (GF) are formed in which the gas to be treated passes through the gas in sequence, is processed, and is then discharged from the other end.

Also, inside the casing (3) are both rotating bodies (1) and (2
) Other same phase portions (B+) in each rotation range.

At (B2), high-temperature regeneration gas () is applied to each rotating body (1) and (2).
I) regeneration gas air path (HF, ), (HF
2) is a partition form.

That is, in the rotation range of each rotating body (1), (2), the specific portion (AI) allows the gas to be processed (G) to pass through.

(A2) is an adsorption area, and the other parts (B1) and (B2) above which pass the regeneration gas (H) are desorption areas,
As a result, as the two rotating bodies (1) and (2) rotate, the adsorbed substances in the gas to be treated (G) (i.e., contained in the exhaust gas from the coating booth) are absorbed in the adsorption areas (A1) and (A2). (painting solvent, etc.) is adsorbed onto the fine activated carbon constituting the rotating bodies (1) and (2), and the adsorbed substance is absorbed into the rotating bodies (1) and the adsorbed substances in the desorption zones (B1) and (B2).
By repeating the desorption from the fine activated carbon in (2) into the high temperature regeneration gas (H), the gas to be treated (G) is
Paint solvents, etc. are continuously separated and collected from the exhaust gas.

In addition, the attachment and detachment areas (B1) and (B2) of each rotating body (1) and (2)
), the regeneration gas air paths (HF, ), (2) desorption area (B, ), (B2
) between them, there is an intermediate heater (4
) is provided.

Furthermore, the regeneration gas (H) that has sequentially passed through both desorption zones (Bl) and (B2) is then sent to a combustion device, where the desorption substances such as solvents in the regeneration gas (H) are incinerated. Process.

To configure both rotating bodies (1) and (2), these rotating bodies (
Among 1) and (2), the fine activated carbon constituting the first rotary body (1) located upstream in the gas flow path (GF') to be treated is the same as the fine activated carbon constituting the second rotary body (2) located downstream. The average pore diameter (d) is larger than that of the average pore diameter (d), and specifically, along with general solvents that are the main adsorbed substances with an average molecular size, Alternatively, desorbable substances whose molecular diameters tend to increase due to deterioration during the adsorption/desorption process and are difficult to desorb after adsorption (e.g., some high-boiling point solvents, ketones that deteriorate through oxidative decomposition, etc.) In this example, the gas to be treated (G) is exhaust gas from a painting booth, which contains a small amount of polymerizable substances (polymerizable substances, etc.). Use a material that is within the range of humans and is suitable for adsorption and desorption (especially desorption) of the above-mentioned separable and adsorbable substances, and on the other hand, as the constituent fine activated carbon of the latter rotating body (2), the average pore diameter (d2) is 14 A material with an average molecular diameter of 1 to 23 people and suitable for adsorption and desorption of a general solvent as the main adsorbed substance is used.

That is, by applying fine activated carbon having the above average pore diameter (di) to the constituent fine activated carbon of the pre-stage rotating body (1), the detachable and adsorbable substances are adsorbed and remain undesorbed.
This prevents the accumulation on the front rotating body (
1) is used as a rotating body exclusively for the detachable and adsorbable substances contained in the gas to be treated (G) together with the main adsorbed substance having an average molecular diameter. The detachable and adhesion substances are appropriately removed from the gas to be treated (G), and thereby the accumulation of the detachment and adhesion substances on the subsequent rotating body (2) is avoided.

For adsorbed substances (general solvents) with average molecular diameters that are not adsorbed and captured by the first rotary body (1) and reach the second rotary body (2), the average molecular size suitable for adsorption and desorption is determined. The latter rotating body (2) made of fine activated carbon having a pore diameter (d2) efficiently removes it from the gas to be treated (G) by adsorption and desorption, and as a result, the rotating body as a whole is caused by the accumulation of detachable substances. This makes it possible to efficiently separate and collect adsorbed substances (general solvents) and detachable and adhesion substances having average molecular diameters while effectively avoiding the decrease in lifespan of (1) and (2).

The rotation axis (la) of the front stage rotor (1) and the rear stage rotor (2)
) are independent rotation axes so that both rotating bodies (1) and (2) can be rotated at mutually different rotational speeds (v1) and (v2), and both rotating bodies In the rotational drives of (1) and (2), the rotational speed (■1) of the first-stage rotary body (1) is set to be smaller than the rotational speed (v2) of the second-stage rotary body (2) (Vl<V2) ( Practically speaking, it is within the range of v,/v2=0.3 to 0.7).

That is, with the above rotational speed setting, the front rotating body (1)
Adsorption time in the adsorption area (A1) and desorption area (B1)
The attachment/detachment time of each of the parts is made longer than that of the latter rotating body (2),
This improves the adsorption/desorption efficiency of the pre-stage rotating body (1) for the detachable substances which are smaller in quantity and have lower adsorption efficiency than adsorbed substances of average molecular size, and which also inherently have lower desorption efficiency. That's how it is.

When configuring both rotating bodies (1) and (2), the front rotating body (1) should be placed closer to the rotational axis (P) than the latter rotating body (2).
) with a small thickness (2+<22) (practically within the range of 11/l!2=0.3 to 0.7)
As a result, the temperature drop during the period from the inlet to the outlet of the regeneration gas (H) in the desorption zone (B+) in the first stage rotor (1) is made smaller than that in the second stage rotor (2). By maintaining the gas (H) at high temperature until the exit of the desorption zone,
This is to further promote the desorption of detachable and adsorbable substances, which are inherently difficult to desorb compared to adsorbed substances of average molecular size, on the upstream rotating body (1).

It should be noted that adsorbing substances such as high boiling point solvents are easily adsorbed and the adsorption zone is short, and the amount of adsorbing substances such as high boiling point solvents is small compared to the adsorbed substance with an average molecular diameter, so Even if the thickness (11) of (1) is small, it will not become saturated in the rotating body within the adsorption time of one rotation, and will be almost completely collected in the first stage rotating body (1), and will be collected in the second stage rotating body (2). There will be no leakage.

Similarly, in this example, for the purpose of further improving the desorption efficiency of the separable adsorbable substance in the pre-rotating body (1), regeneration gas (H ) is set to a higher temperature (t2) than the temperature (t2) of the regeneration gas (H) supplied to the desorption zone (B2) of the subsequent rotating body (2) (for example, t2 for t = 150 °C). =13
0°C).

[Another example]

Next, other embodiments of the present invention will be listed.

(a) Structure of the rotating bodies (1) and (2) The fine activated carbon is not limited to a fibrous form, but may be a granular form.

(b) Rotating shaft core (P) with fine activated carbon as the main component
To configure the rotating bodies (1) and (2) that can be ventilated in the direction,
A formation structure other than forming fine activated carbon into a honeycomb structure may be adopted.

(C) The number of rotating bodies (1) and (2) may be three or more, and in that case, the number of rotating bodies on the upstream side in the series of gas flow paths (GF) to be treated is determined. It may be determined as appropriate whether to use the front-stage rotary body (1) for adsorbing and desorbing detachable substances.

(d) Adsorption area (AI) of each rotating body (1), (2)
, (A2) are arranged side by side in the air path direction, the specific formation structure of a series of gas air paths (GF) to be processed can be modified in various ways.

(e) Each rotating body (1), (2) each desorption area (B1),
Regeneration gas air path (H
FI).

(HF2) may be formed as a series of air paths as in the above embodiment, but may be independent air paths as shown in FIG. 3, and these regenerating gas air paths (HFI),
The specific formation structure of (HF2) can also be changed in various ways.

(f) Various gases such as air can be used as the regeneration gas (H), but in particular, it is necessary to prevent the releasable substances from becoming more difficult to detach due to oxidation and deterioration in the former rotating body (1). In order to improve the desorption efficiency of the separable and adsorbable substances in the front stage rotor (1), regeneration gas (H
) may be applied with an inert gas.

(g) In order to promote the desorption of the separable and adsorbable substance in the first stage rotary body (1), the amount of regeneration gas supplied to the first stage rotary body (1) is made larger than the amount of regeneration gas supplied to the second stage rotary body (2). Also good.

(h) Assuming that the fine activated carbon constituting the first-stage rotary body (1) has a larger average pore diameter than the fine activated carbon constituting the second-stage rotary body (2), the first-stage and second-stage rotary bodies (1), (2)
) The specific average pore diameter of each of the constituent fine activated carbons may be appropriately determined depending on the separable and adsorbable substance to be adsorbed and desorbed and the adsorbed substance having an average molecular diameter.

(i) The rotational speed (■1) of the front-stage rotor (1) and the rotational speed (v2) of the rear-stage rotor (2) are different from each other and when they are the same speed. In either case, it may be determined as appropriate in consideration of adsorption/desorption efficiency, etc.

(j) Thickness of the front rotor (1) in the rotation axis (P) direction (
11) and the thickness (12) of the rear rotating body (2) in the direction of the rotation axis (P), when they are different from each other,
In any case where the thickness is the same, the thickness may be appropriately determined in consideration of adsorption/desorption efficiency, air path pressure loss, etc.

(k) The present invention is not limited to exhaust from a paint booth;
It can be applied to processing various gases in various fields.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of drawings]

1 and 2 show an embodiment of the present invention, with FIG. 1 being a perspective view showing a schematic configuration of the device, and FIG. 2 being a longitudinal sectional view. FIG. 3 is a longitudinal sectional view showing another embodiment of the present invention. (1)...First-stage rotating body, (2)... Second-stage rotating body, (A1), (A2)...Adsorption area, (
B1), (B2)...Desorption area, (GF)...
...To-be-processed gas air path, (HF1), (HF2)・mountain...Regeneration gas air path, (G)......To-be-processed gas, (
H)...Regeneration gas, (d)...Average pore diameter, (v)...Rotation speed, (f)...
・Thickness, (P)...Rotation axis center.

Claims (1)

[Claims] 1. The main constituent material is fine activated carbon, and the rotation axis (P)
A plurality of rotating bodies (1) and (2) that can be ventilated in the direction are provided,
Adsorption areas (A_1) and (A_2) through which the gas to be treated (G) passes through the rotation areas of the rotating bodies (1) and (2), respectively.
and desorption zone (B_1), (B
_2), and the adsorption areas (A_1) and (A_2) of the rotating bodies (1) and (2) are arranged in a series of gas flow paths (GF) in the direction of the air flow path, and Rotating body(
1), (2) the respective desorption areas (B_1), (B_2)
is arranged in the regenerating gas air passages (HF_1) and (HF_2), the rotary gas processing apparatus comprising: the to-be-processed gas air passage (
GF), the rotation in which the fine activated carbon that constitutes the first-stage rotary body (1) located on the upstream side has a larger average pore diameter (d) than the fine activated carbon that constitutes the second-stage rotary body (2) located on the downstream side. type gas processing equipment. 2. The average pore diameter (d_1) of the fine activated carbon constituting the first-stage rotary body (1) is 1.1 times or more the average pore diameter (d_2) of the fine activated carbon constituting the second-stage rotary body (2), The rotary gas treatment apparatus according to claim 1, wherein the thickness is 35 Å or less. 3. The rotary gas processing apparatus according to claim 1 or 2, wherein the rotational speed (v_1) of the first-stage rotary body (1) is smaller than the rotational speed (v_2) of the second-stage rotary body (2). 4. The rotary gas treatment according to claim 1, 2 or 3, wherein the first stage rotary body (1) has a thickness (l) smaller in the rotation axis (P) direction than the second stage rotary body (2). Device.