WO2008050463A1

WO2008050463A1 - Volatile organic compound-containing waste gas treatment system

Info

Publication number: WO2008050463A1
Application number: PCT/JP2006/321806
Authority: WO
Inventors: Susumu Nakano; Tadaharu Kishibe; Kiyoshi Seo
Original assignee: Hitachi, Ltd.
Priority date: 2006-10-25
Filing date: 2006-10-25
Publication date: 2008-05-02
Also published as: JPWO2008050463A1; JP4702453B2

Abstract

This invention provides a volatile organic compound-containing waste gas treatment system for treating a volatile organic compound-containing gas using a gas turbine. In order to prevent damage to components of an electric generator due to attack by a volatile organic compound-containing gas, a volatile organic compound-containing waste gas concentrator is installed between the delivery side in a compressor and a combustor in a gas turbine unit. Air of which the temperature has been raised in the course of compression by adiabatic compression in the compressor is used as heat necessary for eliminating a volatile organic compound from an adsorbent in the concentrator. The volatile organic compound-containing gas is introduced from the delivery side of the compressor into the turbine system. Accordingly, the gas is not leaked into equipments which stand in a row toward an air intake side of the compressor, such as an electric generator, and thus does not damage to these equipments.

Description

Specification

Exhaust gas treatment system containing volatile organic compounds

.Technical field

The present invention relates to a volatile organic compound-containing exhaust gas treatment system, and in particular, heat emitted from a printing factory, painting factory, semi-conductor manufacturing factory, etc., containing volatile organic compounds. This relates to an exhaust gas treatment system containing volatile organic compounds that converts energy into energy such as electric power. Background Technology '.

A VOC-containing exhaust gas treatment system (VOC-containing exhaust gas decomposition / extinguishing system) that uses the heat of oxidative decomposition generated when oxidative decomposition of exhaust gas containing volatile organic compounds (hereinafter abbreviated as VOC) is used for power generation. For example, there are those disclosed in Japanese Patent Application Laid-Open No. 2000-3.6 5 2 3 (Patent Document 1) or Japanese Patent Application Laid-Open No. 2 0 0 1-7 0750 (Patent Document 2). . In these devices, the gas enriched with VOC in the exhaust gas is guided to the gas turbine system, pressurized by the compressor of the gas turbine system, and combusted with the turbine fuel in the combustor, thereby oxidizing and decomposing VOC. At the same time, the heat of decomposition generated at that time is used for power generation. Disclosure of the invention

In the processing systems described in Patent Documents 1 and 2 above, VOC concentrated gas is introduced directly from the intake side of the compressor. There is a possibility of leakage to the generator side along the generator rotor. Yes, acetic acid-based components such as ethyl acetate contained in V-rich gas may corrode the generator parts.

An object of the present invention is cis to handle V_〇 C exhaust gas by using the gas turbine, in Temu, VOC-containing exhaust gas treatment system that can prevent damage to the generator components by concentration VOC Gaz (VO C containing ^Haika;. Scan Decomposition power generation system)

In order to achieve the above object, the present invention provides a concentrator for concentrating VOC in the VOC-containing exhaust gas to compress the gas turbine device. It is configured to be installed on the machine discharge side. '

In the present invention, the VOC concentrating gas is taken into the turbine system from the compressor discharge side by installing a concentrating device on the compressor discharge side. This prevents damage such as corrosion of low-temperature parts such as generator parts. Brief description of the drawings ''

First view: A diagram showing a first embodiment of an exhaust gas treatment system containing a volatile organic compound according to the present invention.

Fig. 2: A schematic diagram of the VOC concentrator.

FIG. 3 is a diagram showing a second embodiment of the volatile organic compound-containing exhaust gas treatment system according to the present invention.

FIG. 4 is a diagram showing a third embodiment of an exhaust gas treatment system containing a volatile organic compound according to the present invention.

FIG. 5 is a diagram showing an embodiment of an exhaust gas treatment system containing a volatile organic compound combined with an absorption refrigerator.

Figure 6: Containing volatile organic compounds in combination with power generation system and absorption refrigerator The figure which shows embodiment of an exhaust gas treatment system.

Fig. 7: Front view of V O C. Concentrator with seal 'structure. .

Fig. 8: Cross section taken along line AA in Fig. 7. BEST MODE FOR CARRYING OUT THE INVENTION

Example-1-"-...-,:-'.: 1...-VOC-containing exhaust gas decomposition treatment system according to the first embodiment of the present invention shown in Fig. 1 (VOC-containing exhaust gas) This will be explained based on the system diagram of the cracking power generation system.

The VOC exhaust gas decomposition treatment system 'shown in Fig. 1 consists of a gas evening bottle device, a VOC exhaust gas blower 9 and a concentrator 7. 'The gas turbine unit consists of a generator 1, a compressor 2, an evening bin 3, and a combination of them. A generator port 4 and a combustor 5. And a regenerative heat exchanger 6. Generator 1 is a generator incorporating a permanent magnet generator port. In addition, since the generator 1 is preferably arranged away from the high temperature component Yuichi 'bin 3, in this embodiment, the generator 1, the compressor 2, and the turbine 3 are arranged around jl. ing. Compressor Air 1 1 is taken into the compressor from the atmosphere through the suction fill 10. The air 11 is pressurized by the compressor 2 and introduced into the concentrating device 7 as compressor discharge air 12. In the concentrator 7, the concentrated VOC is heated and separated into the compressor discharge air 1 2. The concentrated VOC-containing compressed air 13 passes through the regenerative heat exchanger 6 and is sent to the combustor 5. The concentrated VOC-containing compressed air 13 is mixed with the fuel 14 sent to the combustor 5 and combusted in the combustor 5 and sent to the turbine 3 as combustion gas 15. In the turbine 3, the generator row 4 is rotated by the expansion of the combustion gas 15. Turbine exhaust gas 1 6 which expanded in the evening bottle 3 passes through the regenerative heat exchanger 6 and becomes exhaust 1 7 again. To the atmosphere. Here, the turbine exhaust gas 16 is regenerated in the regenerative heat exchanger 6 and heat-exchanged with the concentrated VOC-containing compressed air 13 that has passed through the concentrator 7 to raise the temperature of the concentrated VOC-containing compressed gas 13. . Further, the VOC-containing exhaust gas 18 is sent from the VOC exhaust gas generator 8 to the concentrator 7 by the VOC exhaust gas blower 9.

-Where:-Concentrator 7 has the structure shown in Fig. 2. Cylindrical VOC P 3 adsorbent filling material 40 is filled with adsorbent 41 made of activated carbon or zeolite. The concentration device 7 includes the process of adsorbing organic compounds from the exhaust gas and the process of desorbing from the adsorbent 41. In Fig. 2, the VOC-containing exhaust gas indicated by the arrow 18 passes through the adsorbent 41 in the range c_.d-a-o. The VOC-containing exhaust gas 18 is adsorbed on the adsorbent 4 1, and the VOC content is 90% or more removed by the arrow 19. The adsorbent 4 1 is heated to release VOC from the adsorbent 4 1 again. Most of the V 0 C leaves the adsorbent 4 1 at a temperature of about 1 80. The a-b-o region in the figure is the separation process region, and arrows 1 2 are compressed soot discharge air 1 2 heated by adiabatic compression in the compressor, while this passes through the rotor 4 Q In addition, the VOC adsorbed by the adsorbent 4 1 in a '-b- o is separated and mixed with the compressor discharge air 1 2 and flows out of the concentrator. In other words, the VOC adsorbed at the time of passage between c and d and a by rotating by the driving means such as Moyuichi (not shown) around the rotation axis 4 2 is between a and b. To leave and concentrate. In order to cool the adsorbent 4 1 through which the heated air has passed in order to adsorb VOC again, the cooling area b-c-o in the figure may be provided. Adsorbent cooling air 2 8 is passed through b—c—o section to cool adsorbent 4 1. The chilled adsorbent 41 again enters the VOC adsorption process. Cooling of the adsorbent 4 1 with adsorbent cooling air 2 8 is effective for shortening the cooling time. Although effective, it may be natural cooling without passing through the adsorbent cooling air 28. The exhaust 19 from which the VOC component has been removed is released into the atmosphere. ¾: Owing to the adiabatic compression action in the compressor 2, the temperature of the compressor discharge air 12 is .180-200, and is adsorbed when this air passes through the concentrator 7. Remove VOC component from material 4 1. The m-reducer that passes through the concentrator 7 and eats the VO C component that has been removed ¾ The extracted air 1_2 is introduced into the concentrated VO-.C-containing compressed-air 2 L 3 LX regenerative heat exchanger 6, and then Sent to combustor 5.

In the example shown in Fig. 1, the _P concentrator has an intake flow rate of approximately 60 Nm ³ Zmin, a VOC exhaust gas of 30 Nm Vmin, and an average VO C farming rate of 400 ppm. In 7, the VOC concentration can be increased fivefold, so the VOC concentration contained in the air sent to the combustor 5 is 200 ppm. Due to the thermal energy generated when this concentration of VOC is oxidatively decomposed in the combustor 5, the combustor 5 can reduce the originally required fuel by about 40%. Also, in the combustor 5., the combustion temperature reaches above 100000, so the VOC component is completely resolved. Further, in the heat exchanger 6, the heat recovery rate in the heat exchange is improved as the temperature of the VOC-containing compressed air 13 is lowered. When flowing directly from the compressor 2 into the regenerative heat exchanger 6 without passing through the concentrating unit 7, the air temperature is approximately the same as the discharge temperature of the compressor and has a temperature of about 200. On the other hand, if the concentrator 7 is passed, the heat energy is lost due to VOC separation in the concentrator 7, so that the air temperature at the outlet of the concentrator decreases to about 50. For this reason, in order to further improve the heat recovery efficiency in the regenerative heat exchanger 6, the efficiency of the evening bin system is also improved.

In this example, VOC is oxidatively decomposed by the combustor 5 of the evening bin device, so it can be completely decomposed, and the oxidative decomposition heat generated at that time can reduce the fuel required for turbine operation and generate power. It can be performed. In addition, VO C Is supplied from the concentrator 7 located between the compressor 2 and the regenerative heat exchanger 6 to the evening bottle apparatus, so that only the high temperature parts of the regenerative heat exchanger 6 and the combustor 5 are touched. Since it is not supplied to the low-temperature and normal-pressure areas such as the compressor 2 intake side and the generator 1, it has the effect of preventing damage to the turbine parts due to VOC, such as corrosion of parts due to leakage of the low-temperature parts.

In addition, in this patent document 2._, the heat source is required for the processing system Λ, and the concentrated air is directly introduced into the compressor of the turbine. The compressor performance decreases as the intake air temperature rises ± and the turbine output decreases. Turbine performance deteriorates because energy for heating is required and the concentrated gas is directly sucked. Furthermore, in the treatment system described in Patent Document 1, the heat source for removing VOC is obtained from the exhaust gas of the turbine, and no special heat source is required, but before the concentrated air is taken into the compressor, the air temperature is reduced by the cooling device. Is reduced. For this reason, the system needs a device to cool the compressor intake air. ',

On the other hand, in this embodiment, the compressor discharge air 12 raised in temperature by the adiabatic crushing action in the compressor 2 is used as the heat source for the heat detachment of the concentrator 7, so that No need for a heat source. In this embodiment, since the concentrating device is arranged on the compressor discharge side, the temperature of the compressor intake air is not increased by the heating source of the concentrating device.

In the embodiment shown in Fig. 1, the regenerative heat exchanger 6 was installed in the evening bin. However, even in the evening bin system without the regenerative heat exchanger 6, corrosion of low temperature parts, etc. can be prevented. The same effect is obtained that the compressor discharge air 12 can be effectively used as a heating source for the contribution of VOC to power generation and for the heat separation of the concentrator 7.

Example 2 FIG. 3 is a view showing another embodiment of the present date. FIG. 3 is a system similar to the VOC-containing exhaust gas treatment system shown in FIG. 1, but the intake intake of the compressor 2 of the turbine unit is different from the system shown in FIG. In FIG. 1, all the intake air of the compressor 2 is taken from the atmosphere side. However, in the embodiment of FIG. 3, the air of the compressor 2 fles from the VOC exhaust gas generator 8 through the concentrator 7 and is discharged. Adsorbent 4_Λ in the concentrator. Since the VOC component has been removed, the exhaust gas after passing through the concentrator 7 on the intake side of the compressor 2

29 contains almost no y O C component. This air is compressed to operate the evening bottle. VOCs concentrated by the concentrator 7 are oxidatively decomposed in the combustor .5, and the fuel that the turbine system originally needs can be reduced by the energy released at that time to generate electricity. :

In this example, in addition to the effects listed in Example 1, the VOC exhaust gas storm blower 9 that supplies VOC-containing exhaust gas 18 to the concentrator unit 9 is supplied in an amount equal to the amount of intake from the compressor 2. Because it can be reduced, the power can be reduced by approximately 20%.

Example 3.

FIG. 4 shows another embodiment of the present invention. Fig. 4 shows basically the same configuration as Fig. 1. The difference is that the concentrator 7 has a cooling air supply line for cooling the adsorbent. Adsorbent cooling air blower blower 20 sucks air and blows it to concentrator 7 to cool adsorbent 41 after VOC release. The cooling air exhaust 21 after passing through the adsorbent is released into the atmosphere as it is. The cooling air blowing line in Fig. 4 can also be applied to the system configuration shown in Fig. 3.

In this embodiment, since the adsorbent 4 1 in the heated state after the VOC separation of the concentrator 7 can be cooled in a short time, the space of the concentrator 7 can be reduced, and the VOC There is an effect that the exhaust gas treatment power generation system can be downsized.

Example 4.

FIG. 5 is a view showing another embodiment of the present invention. The previous examples shown in Fig. 1, Fig. 3, Fig. 4 and Fig. 4 use VOC for power generation, but the system shown in Fig. 5 uses VOC for cold supply. It is for use. .—The VO C_ containing exhaust gas treatment system shown in FIG. 5 is composed of a gas turbine device, a VOC exhaust gas blower 9 and a concentrating device 7, and operating using the energy of the turbine exhaust gas. .2 consists of six. Turbine exhaust gas 30 passing through the regenerative heat exchanger 6 passes through the pipe 3 1 through the three-way valve 2 2 and partly passes to the concentrator 7, and the rest passes through the pipe 23 and absorbs the cooling. It is sent to the waste heat recovery machine 25, which is the heat source for the freezer 26, and exchanges heat with the refrigerant in the P refrigerating machine 26. The method of blowing the VOC-containing exhaust gas to the concentrator 7 is the same as the method shown in Fig. 4, but after the adsorbent cooling air 28 has passed through the concentrator 7, it is not released into the atmosphere as it is. Return to the turbine exhaust pipe 3 1. Since the adsorbent cooling air 28 passes through the concentrator 7 and cools the adsorbent, it is heated to about 140 at the outlet of the concentrator. The cooling air exhaust 21 after passing through the adsorbent and the evening exhaust gas 30 sent from the regenerative heat exchanger are mixed to separate the VO adsorbed on the adsorbent 4 1 of the concentrator 7. Set the temperature appropriately and send it to the separation side of the concentrator 7. The VOC-concentrated gas 27 after passing through the concentrator 7 is sent to the exhaust heat recovery device 25 of the absorption refrigerator. This VOC-containing gas is used as a fuel for replenishment in the exhaust heat recovery device 25. Until the VOCs self-ignite, use an ignition gas to assist combustion. The ignition gas 3 3 is sent from the ignition gas cylinder 3 2 to the exhaust heat recovery device 25 via the supply valve 3 4. It is ignited by a spark plug device (not shown) to generate a VOC combustion seed and maintain the oxidative decomposition reaction of VOC. The After the oxidative decomposition of VOC progresses and the temperature rises and reaches the self-decomposition temperature of VOC; the supply of ignition gas 33 is stopped. .

In this embodiment, the heat of oxidative decomposition of VO C can be used in addition, so the absorption refrigeration and the cold supply capacity of the machine can be increased. Similarly to Examples 1 to 3 above, the VOC-containing exhaust gas 18 is not introduced into the compressor intake side, but the QC-containing exhaust gas ¾ is introduced into the compressor outlet side. This has the effect of preventing damage to turbine parts due to VOO, such as corrosion of parts due to leakage to the parts. ,.

Example 5

FIG. 6 is a diagram showing another embodiment of the present invention. Fig. 6 shows a system that uses both VOC shown in Fig. 4 for power generation and VOC shown in Fig. 5 as a system that uses the absorption chiller 26 for generating cold heat. The In this embodiment, a large amount of exhaust gas containing V O C can be treated, and there is an effect that the heat of oxidation decomposition of V O C can be converted into both power generation and cold generation. In Fig. 6, the same effect can be obtained by using the power generation system shown in Fig. 1 or Fig. 3.

Example 6

In Examples 1 to 5, a concentration apparatus having the structure shown in FIGS. 7 and 8 may be used. This concentrator separates the VOC exhaust gas from the concentrated VOC-containing air, so it needs to be sealed against the VOC concentration, and the enrichment air uses the compressor discharge air, so it has a higher pressure than the VOC exhaust gas. Therefore, a seal structure against pressure is also required. Fig. 7 shows a cross section in a direction perpendicular to the concentrator. In the embodiment of FIG. 7, the circular cross section is divided into eight equal parts, and each divided region is surrounded by an outer frame 10 1, an inner frame 1 0 2, and a radial partition frame 1 0 3. The VOC adsorbent 41 is contained in this. Now, the divided areas are numbered 1 1 0, 1 1 1 and so on from the upper right. The direction of rotation is the direction of arrows 104. The divided area 11 1 is an area through which the compressor discharge air 1 2 passes, and the air that has passed through this area sends concentrated V 0 C to the combustor 5 of the gas evening bottle. Regions 1 1 3 to 1 1 7 are regions where V C exhaust gas 18 passes through the V OC exhaust gas and the V OC adsorbent weeding region. Regions 1 1 0 and 1 1 2 are regions that are not in contact with either the VOC-containing exhaust gas 18 or the compressor discharge air 1 2. Lines 10 5 indicated by broken lines in the radial direction are protruding labyrinth seals installed on both end faces of the concentrator cylinder. FIG. 8 is a cross-sectional view taken along the line A_A of FIG. Protrusion 1 0 5 is provided on the end plate 1 0 6 of the concentration device to seal the regions 1 1 1 and 1 1 7 or 1 1 1 and 1 1 3. ,

The method of rotating the VOC adsorbent filling port overnight can be either continuous or intermittent. 'In the case of continuous rotation, there is an advantage that the amount of air supplied to the combustor 5 and the VOC concentration are constant in relation to the rotation, but the low-pressure low-temperature VOC exhaust gas and the high-pressure high-temperature compressor discharge air 1 In order to seal 2 during rotation, the interval between the projections 10 5 must be such that the end face of the radial partition frame 1 0 3 is in contact with the projection 1 0 5 during rotation.

The rotation by intermittent operation is fixed at the position shown in FIG. 8 when the rotor is stationary, that is, the position where the compressor discharge pipe 10 7 and the radial partition frame 10 3 match. After a certain period of time, the VOC adsorbent filling row 40 rotates quickly and the next divided area is fixed. In this intermittent operation, as shown in FIG. 8, the projections 105 are densely arranged on the end plate 106 side of the concentrating device facing the end face of the radial partition frame 103. Both low-pressure and low-temperature VOC-containing exhaust gas 1 8 and high-pressure and high-temperature compressor discharge air 1 2 have a sealing effect. Demonstrated. However, because of intermittent operation, before and after low speed rotation, fuel; t

The amount of air supplied to 5 and the V O C concentration fluctuate slightly. In the case of intermittent operation, the VOC adsorbent-filled rotor 40 is not limited to a cylinder but may be a cylinder with a regular polygonal cross section.

The concentrator having the structure shown in FIGS. 7 and 8, the area ratio _ V shed C © concentrate that passes the compressor unloading Φ gas 1 ² and VO .C exhaust gas - 5 times -. In Do Ru. In FIG. 7, the adsorbent cooling air 28 may be passed through the divided areas 1 1 3. In this case, the concentration is quadrupled.

Claims

2 Scope of request

1. It has a compressor that sucks air and pressurizes, and an adsorbent that adsorbs a volatile organic compound from a gas containing a volatile organic compound, and introduces the pressurized air discharged from the compressor, A concentrator that heats and desorbs the adsorbed volatile organic compound from the adsorbent; and a combustor that injects fuel into the pressurized air containing the volatile organic compound passing through the concentrator and burns it. An exhaust gas treatment system containing a volatile organic compound, characterized in that it has an evening bin that operates by expansion of combustion gas generated by the combustor.

2. A compressor that boosts air by taking in air, a combustor that injects fuel into the boosted air discharged from the compressor, and burns, and operates by expansion of combustion gas generated by the combustion A turbine that generates power by rotating the turbine, the compressor, the turbine, and the generator are arranged on one axis, and the compressor is arranged between the turbine and the generator. In a gas turbine apparatus, a gas containing a volatile organic compound is introduced to adsorb the volatile organic compound, and a heated gas is introduced so that the adsorbed volatile organic compound is separated into the heated gas. And a pressurized air discharge side of the compressor is connected to a heated gas introduction side of the concentrated device, and a pressurized air inflow side of the combustor is connected to a heated gas discharge side of the concentrator. The A gas turbine device that is characterized.

3. A gas having a volatile organic compound is introduced into a concentrating device having an adsorbent, the volatile organic compound is adsorbed, heated by pressurized air discharged from a compressor that takes in the air and pressurizes, The volatile organic compound is desorbed from the concentrator, and the desorbed volatile organic compound flows into the combustor together with the pressurized air, and is oxidatively decomposed in the combustor. Compound processing method.

4. The volatile property according to claim 1, wherein a regenerative heat exchanger for exchanging heat between the exhaust gas of the turbine and the pressurized air containing the sporadic organic compound is disposed upstream of the combustor. Organic compound-containing exhaust gas treatment system.

5—In claim 1, the air that is evacuated by the compressor—the air after passing the gas containing the volatile organic compound through the adsorbent of the concentrator—is defined as: An exhaust gas treatment system containing a spontaneous organic compound.

6. The volatile composition according to claim 1, wherein after the volatile organic compound is removed by heating, the temperature of the adsorbent is lowered by blowing cooling air to the adsorbent. Organic compound-containing exhaust gas treatment system.

7. A compressor that boosts the air pressure by sucking air, a combustor that injects fuel into the boosted air discharged from the compressor, and operates by expansion of combustion gas generated by the combustor. A turbine, a generator that generates electric power by rotating the bin, and an adsorbent that adsorbs a volatile organic compound from a gas containing a volatile organic compound, A concentrating device that heats and separates the adsorbed volatile organic compound from the adsorbent, and an exhaust gas that is discharged from the evening bottle to collect exhaust heat. Exhaust gas whose content of volatile organic compounds has been increased by heating and desorbing is introduced as a fuel for remedy, and an exhaust heat recovery device that oxidizes and decomposes the volatile organic compounds by combustion, Cold Volatile organic compound-containing exhaust gas treatment system characterized by having an absorption refrigerating machine operated by.

8. The concentration device according to claim 7, wherein the concentrating device lowers the temperature of the adsorbent by blowing cooling air to the adsorbent after the volatile organic compound is heated and separated. Four

The volatile organic compound-containing exhaust gas treatment system is characterized in that the cooling air after cooling is mixed with the exhaust gas from the bottle in the evening and supplied to the concentrating device as a heat release gas of the compression device.

,

9. The concentration device according to claim 1, wherein the concentrating device has a cylindrical main body filled with the adsorbent, and the main body rotates about the cylindrical axis as a rotation axis, so that the adsorption is preliminarily provided. A volatile organic compound that absorbs and desorbs volatile organic compounds by alternately passing through the range where volatile organic compounds are absorbed by heat. The main body has a plurality of regions partitioned by a main body outer frame, a main body frame, and a plurality of radial partition frames along the rotation direction, and on both end surfaces of the cylindrical main body, Volatile organic compound concentrating device provided with an end plate having a sealing structure that separates the region for adsorbing the volatile organic compound from the region for heat-releasing the volatile organic compound. Organic compound-containing exhaust gas treatment system. '