JPH08155252A - Improvement of regeneration efficiency in concentration type deodorizer - Google Patents

Abstract

PURPOSE: To give an enough amt. of heat being not too high temp. and to improve regeneration efficiency by partitioning a regenerating zone into a plurality of regenerating zones in the circumferential direction and making a heated air for regeneration flow in each regenerating zone. CONSTITUTION: A regenerating zone 3 is partitioned into a plurality of zones in the circumferential direction, e.g. into two zones. In addition, two partitioned regenerating zones are sealed so as to exhibit no leakage each other. Heated air for regeneration heated at a specified temp. by means of a heater 6 is continuously passed through the regenerating zone 3a adjoining to an adsorbing zone at first, and then, it is passed through the regenerating zone 3b adjoining to a cooling zone in the opposite direction to the direction of the heated air passing through the regenerating zone 3a. Temp. distribution of a honeycomb rotor in the thickness direction is uniformed thereby and improvement of regeneration efficiency is attempted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for enhancing the regeneration efficiency in a concentration type deodorizing device.

[0002]

2. Description of the Related Art Volatile organic compounds (VO
C) (hereinafter, referred to as VOC) treatment device includes combustion method, adsorption method, biological method, etc., but with respect to exhaust gas with low gas concentration and large air volume, these methods require equipment cost and operation cost. It is not often used because it becomes high. Generally, a method is adopted in which these exhaust gases are concentrated to reduce the amount of gas and the exhaust gas is burned.

A method which has been widely adopted as a method for concentrating exhaust gas having a low concentration and a large air volume has been that a VOC is once adsorbed on an adsorbent having a function of adsorbing VOC, for example, a honeycomb rotor carrying activated carbon or zeolite. It is adsorbed and desorbed with a small amount of heated air.

The mechanism of this concentration is shown in FIGS. FIG. 7 is a schematic perspective view of a concentrating type deodorizing apparatus of a conventional example, and FIG. 8 is a schematic flow diagram of a method of the conventional example. Figure 7
At the honeycomb rotor 1, which is the structure of the concentrating device
Is continuously rotated at a constant speed in the counterclockwise direction indicated by arrow A by the drive motor 5. The honeycomb rotor 1 has a V
It is divided into an adsorption zone 2 for adsorbing OC, a regeneration zone 3 for desorbing the adsorbed VOC to restore the adsorption ability of the honeycomb rotor, and a cooling zone 4 for cooling the honeycomb rotor heated in the regeneration zone. Further, each zone is provided with a seal structure (not shown) so that gas does not leak to each other.

The rotation of the honeycomb rotor portion causes the adsorption zone 2, the regeneration zone 3 and the cooling zone 4 to move continuously in this order. The target processing gas is passed through the adsorption zone in the direction indicated by the arrow B, and the VOC contained in this gas is adsorbed by the adsorbent arranged in the honeycomb rotor, becomes a clean (purified) gas, and is released to the atmosphere. To be done. The portion of the honeycomb rotor that has adsorbed the VOCs enters the regeneration zone, and in this regeneration zone, a small amount of the heating air heated by the heater 6 is passed through the portion of the honeycomb rotor, The VOCs adsorbed on the rotor are desorbed and become concentrated gas.

Since the honeycomb rotor is naturally heated when desorbing VOCs with heated air, the adsorption capacity of the adsorbent for adsorbing VOCs is greatly reduced. In order to restore the adsorption capacity, the part of the honeycomb rotor is cooled by passing atmospheric air in the next cooling zone and moves to the adsorption zone again.

Generally, the air for regeneration (desorption) and the air for cooling are used as a series of streams to recover waste heat. That is, the atmospheric air enters the cooling zone, where it receives the sensible heat accumulated in the honeycomb rotor to become warm air, enters the heater 6 as indicated by arrow C, and is required by the heater 6 for regeneration. It is heated to a certain temperature, enters the regeneration zone, and is taken out as a concentrated gas as shown by arrow D. The enriched gas containing VOCs desorbed in the regeneration zone is then processed by catalytic combustion or direct combustion methods.

[0008]

In the concentration phenomenon by the adsorbent, the adsorption is an exothermic phenomenon, and the regeneration (desorption) is caused.
Is an endothermic phenomenon. Therefore, the amount of heat required for regeneration is V
The amount of heat for desorption of OC and the amount of heat for heating the honeycomb rotor are required. However, the temperature of the heated air for regeneration is restricted by the heat-resistant temperature of the equipment (particularly the sealing material), and is also restricted by the deterioration of the gas components at high temperatures and the adverse effect on the adsorbent due to the polymerization reaction. Receive. Therefore, the minimum required temperature is desirable. At the same time, of course, the amount of regenerated heating air is naturally limited in terms of the concentration ratio. Therefore, a sufficient amount of heat necessary to completely regenerate the honeycomb rotor that has adsorbed gas components must be given under the above-mentioned constraint conditions, and effective regeneration by this limited amount of heat is required. .

Generally, the concentration ratio of the concentration type deodorizing device is 5
~ 15 times. Further, this concentration ratio is determined by the conditions of the target processing gas and the like. At the same time, if the concentration of the processing gas changes, the concentration of the concentrated gas also changes in proportion to the concentration of the processing gas. That is, one of the processing gas amount
The air determined to be / 5 to 1/15 is introduced into the cooling zone, and the honeycomb rotor heated in the regeneration zone is cooled in this cooling zone. After that, this is further heated to a predetermined temperature by the heater 6 and enters the regeneration zone, and the VOC adsorbed on the honeycomb rotor is desorbed to become a concentrated gas.

When the concentration ratio becomes high, the amount of heating air for regeneration becomes small, so that a sufficient amount of heat cannot be obtained and complete regeneration cannot be performed. That is, if a sufficient amount of heat is not applied, the regeneration is near the surface where the regenerated heated air is introduced, the regeneration on the downstream side is insufficient, and the adsorption function of the honeycomb rotor is not sufficiently restored. Moreover, if the temperature of the regenerated heating air is too high,
There is also a risk of deterioration of the components of the processing gas, polymerization, etc., which is not preferable for the honeycomb rotor and is also restricted by the heat resistant temperature of the apparatus.

In FIG. 8, reference numeral 8 is a reproducing fan, and reference numeral 9 is an air volume adjusting damper.

Therefore, an object of the present invention is to provide the heating air for regeneration so as to have a substantially uniform temperature distribution in the thickness direction in the regeneration zone of the honeycomb rotor,
It is an object of the present invention to provide a method for enhancing the regeneration efficiency in a concentration type deodorizing device configured to give a sufficient amount of heat without being too hot.

[0013]

To achieve the above object, the present invention provides a method for enhancing regeneration efficiency in a concentration type deodorizing apparatus having a honeycomb rotor divided into an adsorption zone, a regeneration zone and a cooling zone. The zone is divided into a plurality of regeneration zones in the circumferential direction, and heated regeneration air is flown into each regeneration zone.

[0014]

EXAMPLES Next, examples of the present invention will be described.

Example 1 FIG. 1 is a schematic flow chart of Example 1 of the method of the present invention. In each of the following examples including the first example, members having the same functions and configurations as the members used in the conventional example are designated by the same reference numerals.

In FIG. 1, the reproduction zone 3 is divided into a plurality of zones in the circumferential direction. For example, in this embodiment,
It is divided into two. The reproduction zones divided into two are sealed so that there is no leak between them. For convenience of explanation, one of the divided regeneration zones adjacent to the adsorption zone is labeled with 3a, and the other adjacent to the cooling zone is labeled with 3b. In the first embodiment, the regeneration heating air heated to a predetermined temperature by the heater 6 is continuously passed through the regeneration zone 3a adjacent to the adsorption zone first, and then the regeneration zone 3a. It is passed through the regeneration zone 3b adjacent to the cooling zone in the opposite direction of the heated air. As a result, the temperature distribution in the thickness direction of the honeycomb rotor is made uniform, and the regeneration efficiency is improved.

Example 2 FIG. 2 is a schematic flow chart of Example 2 of the method of the present invention. As is apparent from FIG. 2, Example 2 is the same as Example 1 except that the order in which the heating air for regeneration is passed through the divided regeneration zones is different. That is, the heating air for regeneration is first passed through the regeneration zone 3b adjacent to the cooling zone and then the regeneration zone 3b.
The regeneration zone 3a adjacent to the adsorption zone is passed in the direction opposite to the direction of the heated air passing through b. As a result, similar to Example 1, the temperature distribution in the thickness direction of the honeycomb rotor is made uniform, and the regeneration efficiency is improved.

(Embodiment 3) FIG. 3 is a schematic flow chart of Embodiment 3 of the method of the present invention. Example 3 is carried out in that, when the heating air for regeneration is introduced into the regeneration zone divided into two, the flow path for guiding the heating air to the regeneration zone is branched, and the air volume adjustment damper is provided in each branch passage. Different from Examples 1 and 2. That is, as is apparent from FIG. 3, two flow paths from the heater 6 to the regeneration zones 3a, 3b are provided by branching, and the air flow rate adjusting dampers 10B, 10A are provided in the branch paths.
Is provided, and the amount of heated air introduced into the regeneration zones 3a, 3b is adjusted by the respective air volume adjustment dampers 10B, 10A. The heated air discharged from each of the regeneration zones 3a and 3b is merged again, and the total air volume is adjusted by the air volume adjustment damper 9 via the fan 8. As a result, the temperature distribution in the thickness direction of the honeycomb rotor is made more uniform, and the regeneration efficiency is further improved.

(Embodiment 4) FIG. 4 is a schematic flow chart of Embodiment 4 of the method of the present invention. Example 4 is carried out in that when the heating air for regeneration is introduced into the regeneration zone divided into two, the flow path for guiding the heating air to the regeneration zone is branched and the air flow rate adjustment damper is provided in each branch passage. Same as Example 3, but the direction in which the heating air for regeneration is passed through the divided regeneration zones is different. That is, in the third embodiment, the heated air passes through the regeneration zone 3a in the direction opposite to the process gas passage direction (indicated by the arrow B), and passes through the regeneration zone 3b in the same direction as the process gas passage direction. However, in the fourth embodiment, conversely, the heated air is passed through the regeneration zone 3a in the same direction as the passage direction of the processing gas, and the regeneration zone 3b is opposite to the passage direction of the processing gas. Be passed through. As a result, as in the case of Example 3, the temperature distribution in the thickness direction of the honeycomb rotor is made more uniform, and the regeneration efficiency is further improved.

Next, in order to confirm the effect of the present invention, the conventional example and the present invention will be compared and examined. In the conventional concentration method (FIGS. 7 and 8), since the amount of heating air for regeneration is determined by the concentration ratio, a sufficient amount of heat cannot be obtained especially when the concentration ratio becomes high, and the VOC adsorbed honeycomb rotor is completely removed. It is not regenerated, and as a result, the adsorption efficiency is naturally lowered. For example, when the temperature of the heating air for regeneration is 160 ° C. and the concentration ratio increases, the amount of heating air for regeneration decreases and the outlet temperature of the regeneration zone decreases to about 40 ° C. Depending on the physical properties of the VOC, when the temperature of the regenerated air is 60 ° C or less, the desorption phenomenon is not expected so much, and the VOC remains without being desorbed on the downstream side of the regeneration zone of the honeycomb rotor. Loss of functionality.

FIG. 5 is a schematic diagram for explaining the adsorption capacity. FIG. 5a shows an adsorption, regeneration and cooling cycle with a sufficiently regenerated adsorption capacity, and FIG. 5b shows an adsorption, regeneration and cooling cycle with insufficient regeneration. In the case of FIG. 5a, the adsorption capacity has a margin and the adsorption efficiency is high. In the case of FIG. 5b, the regeneration efficiency is low and the adsorption capacity is insufficient,
Naturally, the adsorption efficiency becomes low. In particular, when a breakthrough region (d) is formed, the efficiency is extremely reduced. In FIG. 5, reference numeral (a) indicates the thickness of the honeycomb rotor, reference numeral (b) indicates the margin area of the honeycomb rotor, and reference numeral (c) indicates the effective thickness of the honeycomb rotor. Further, in FIG. 5, the hatched portion indicates the VOC adsorption area.

In the present invention, under the limited regeneration conditions, the temperature distribution in the thickness direction of the honeycomb rotor in the regeneration zone is made uniform, and the honeycomb rotor in the adsorption zone is always maintained in the state shown in FIG. 5a. It is what

FIG. 6 is a graph showing the temperature distribution in the thickness direction of the honeycomb rotor in the regeneration zone depending on the regeneration method. In the figure, the broken line shows the ideal temperature distribution. That is, it is ideal that the temperature distribution has substantially the same height in the thickness direction. FIG. 6a shows a temperature distribution according to the conventional reproducing method as shown in FIGS. 7 and 8, FIG. 6b shows a temperature distribution in the first and second embodiments of FIGS. 1 and 2, and FIG.
The temperature distribution in Examples 3 and 4 of FIG. 3 and FIG. 4 is shown. In the case of FIG. 6a, the temperature difference between both ends of the honeycomb rotor is large, and regeneration efficiency cannot be expected on the downstream side where the temperature is low.
Further, the temperature on the upstream side inevitably becomes high, which is not preferable for the above reason. In the case of FIG. 6b, the temperature distribution is considerably improved compared to the conventional method. In the case of FIG. 6c, the temperature distribution is further improved and is close to the ideal temperature distribution.

[0024]

As described above, according to the present invention,
A method for increasing the regeneration efficiency in a concentrating deodorizing device configured to provide a sufficient amount of heat without excessively high temperature by supplying heating air for regeneration so that a temperature distribution in the regeneration zone of a honeycomb rotor is substantially uniform in the thickness direction. Is obtained.

[Brief description of drawings]

FIG. 1 is a schematic flow chart of Example 1 of the method of the present invention.

FIG. 2 is a schematic flow chart of Example 2 of the method of the present invention.

FIG. 3 is a schematic flow chart of Example 3 of the method of the present invention.

FIG. 4 is a schematic flow chart of Example 4 of the method of the present invention.

FIG. 5 is a schematic diagram for explaining adsorption capacity.

FIG. 6 is a graph showing the temperature distribution in the thickness direction of the honeycomb rotor in the regeneration zone depending on the regeneration method.

FIG. 7 is a schematic perspective view of a conventional concentrated deodorizing device.

FIG. 8 is a schematic flow chart of a conventional method.

[Explanation of symbols]

 1 Honeycomb rotor 2 Adsorption zone 3 Regeneration zone, 3a, 3b Divided regeneration zone 4 Cooling zone 6 Heating heater 8 Regeneration fan 9 Air volume adjustment damper 10A, 10B Air volume adjustment damper

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location B01D 53/34 ZAB

Claims (7)

[Claims] 1. A method for enhancing regeneration efficiency in a concentration type deodorizing device having a honeycomb rotor divided into an adsorption zone, a regeneration zone and a cooling zone, wherein the regeneration zone is divided into a plurality of regeneration zones in a circumferential direction. A method comprising flowing heated air for regeneration into a regeneration zone. 2. The method according to claim 1, wherein the reproduction zone is divided into two parts. 3. The method according to claim 2, wherein the heating air for regeneration is caused to flow in one direction with respect to one divided regeneration zone, and the heating air for regeneration is caused to flow in the opposite direction with respect to another regeneration zone. A method characterized by the following. 4. The method according to claim 3, wherein the heating air for regeneration flowing in a certain direction with respect to the regeneration zone is subsequently flowed to another regeneration zone. 5. The method according to claim 1, wherein the heating air for regeneration is branched, and the branched heating air for regeneration is flown to each regeneration zone. 6. The method according to claim 5, wherein an air flow rate adjustment damper is provided in each branch path for branching the heating air for regeneration.
A method comprising adjusting the amount of heating air for regeneration flowing in each branch. 7. The method according to claim 5, wherein when the branched heating air for regeneration is caused to flow through the respective regeneration zones, it flows in directions opposite to each other with respect to the respective regeneration zones.