JPH11188223A - Opeeration control device for cooling tower of viscous fume removal device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control an operation of a cooling tower with the most suitable condition, in a viscous fume removal device and also to prevent damage and fault of a cooling water feeding means due to freezing of a water pipe line to atomizing nozzles, even in a winter season during the operation is stopped. SOLUTION: In the cooling tower provided with water feeding means 18, 19 and pressurized air feeding means 20, 21 for feeding cooling water and pressurized water to the atomizing nozzles 10... via pipe lines 15, 16 from the lower part of the tower, temperature detecting means 26, 27 are equipped in an upstream region where fume-containing gas is introduced into the cooling tower 1 and in the downstream region where the gas is fed to a filter part 2 from the cooling tower 1, and a circuit for controlling the operations of the water feeding means 18, 19 and the air feeding means 20, 21 based on the temperatures detected with the means 26, 27, is provided and water discharge means 30, 31 for discharging water in the pipe line 15 are provided. The control circuit delay an operation stop time of the air feed means 21 later than it of the water feed means 18, 19 at an operation stop time, and feed of pressurized air is programmed to be continued even after completion of feeding the cooling water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for removing sticky fumes, and more particularly to a cooling tower incorporated in the apparatus for controlling the temperature of a fume-containing gas, and more particularly to an apparatus for controlling the operation thereof. About.

[0002]

2. Description of the Related Art As an apparatus for achieving effective removal of sticky fume, the maximum effect of inertial collision is applied, and fine fume particles are enlarged and re-scattered in a filter section, and this is dispersed in a mist separation section. A sticky fume removing device (HEAF) for collecting is practically used. The removal device is particularly effective for removing sticky micro fumes such as plasticizer fumes, asphalt fumes and fumes during rubber compounding and vulcanization from a vinyl factory. Japanese Utility Model Publication No. 56-39542, Japanese Utility Model Publication No. 57-901, and Japanese Patent Publication No. 59-12330, which are related to the sticky fume removing apparatus, are documents that constitute the prior art.

[0003] The sticky fume removing device is a kind of filtering device, and when the fume-containing gas passing through the device is at a high temperature, the filter section can effectively collect organic substances in the gas. Because it is not possible, generally, a cooling tower is incorporated as a pre-process of the filter section, a fume-containing gas is passed through the cooling tower, and the cooling is performed to increase the fume collection efficiency, including gasified organic substances. I have. The above-mentioned cooling tower is provided with an appropriate number of atomizing nozzles for spraying water in the form of a mist, inside the tower, near the inlet where the fume-containing gas is usually introduced, and cooling the fume-containing gas. It is also designed to achieve good gas-liquid contact between the gas and the mist. Usually six to eight atomizing nozzles are arranged around the fume-containing gas inlet. Conventionally, in this cooling tower, sludge and the like in the fume-containing gas adhere to the cooled atomizing nozzle and solidify. There is a problem that the performance decreases over time. Therefore, the present inventor has proposed means for solving this problem as disclosed in Japanese Utility Model Laid-Open No. 3-3424.

[0004]

By the way, in the above-mentioned adhesive fume removing apparatus, the cooling water and the pressurized air are sprayed in order to make the water for cooling into a mist and to continuously spray it into the cooling tower. Means and apparatus for feeding the forming nozzle will normally be provided. Then, it is necessary to determine the optimal conditions for the operation and operation of those means and the apparatus from the viewpoint of appropriately cooling the fume-containing gas and obtaining high fume collection efficiency. For example, if an excessive amount of cooling water is supplied into the cooling tower, the cost of the subsequent operation is considerably increased, the amount of waste water discharged from the mist separator is increased, and the processing burden is also increased. . However, such a study has not been reported in any of the prior art documents. Further, the means and apparatus for continuously supplying the cooling water and the pressurized air to the atomizing nozzle will be constituted by, for example, a water supply pump and a water supply tank, a pressurized air source, and a switching valve. The problem here is that due to the structure of the cooling tower, two pipes (a water pipe and an air pipe) connecting the water supply pump and the pressurized air source to, for example, 6 to 8 atomizing nozzles are formed. In that the cooling water and pressurized air must be introduced from a water supply pump and a pressurized air source on the side of the cooling tower, through the lower part of the cooling tower, and into the atomizing nozzle inside the tower. is there. Cooling towers are usually
Being installed at or slightly above ground level, the two conduits will have a complex branching and piping configuration that is guided with a very gentle ascending slope. Therefore, after the operation of the sticky fume removing device (cooling tower) is completed, that is, after the water supply pump is stopped, the cooling water is supplied into the water pipe between the water supply pump / tank and the appropriate number of atomizing nozzles. There is a structural disadvantage that it is likely to remain. In summer, there is no serious problem, but in winter, the water pipe may be broken or damaged due to freezing of cooling water. As a method of preventing freezing of the water pipe between the water supply means and the atomizing nozzle, a method of first covering the circumference of the water pipe with a heat insulating material such as styrene foam can be considered. However, this method is not only expensive, but also because the construction of the water line between the water supply means and the atomizing nozzle is quite complicated, the coating of the heat insulating material is a very cumbersome task, and in particular, it is already installed. In a cooling tower, it is difficult to completely cover the heat insulating material, and furthermore, the operation involves a great deal of difficulty, so that the above method cannot be adopted immediately.

The present invention has been made in view of such circumstances, and an object thereof is to control the operation of a cooling tower of a sticky fume removing apparatus under optimum conditions. An object of the present invention is to provide an operation control device for a cooling tower in which the cooling water supply means is not damaged or broken due to freezing of a water pipe to an atomizing nozzle even in winter when operation is stopped.

[0006]

Means for Solving the Problems The present inventor has made intensive studies to solve the above-mentioned problems. As a result, the fume-containing gas is introduced into the cooling tower by using a temperature detecting means such as a thermometer or a temperature sensor. It is installed in the upstream area and the downstream area fed to the filter section from the cooling tower, and based on the temperature detected by these means, the operation of the water supply pump and the air supply means is started, and the detected temperature It has been found that if the supply of cooling water to the atomizing nozzle is controlled such that the temperature of the cooling tower is maintained at a constant temperature, the operation of the cooling tower can be controlled under optimum conditions. Further, as a result of intensive research, the present inventor has found that when the operation of the cooling tower is terminated, the operation of the supply means of the pressurized air is stopped with a delay of some time from the stoppage of the operation of the water supply pump. From the time of stop, only pressurized air is supplied to the inside of the atomizing nozzle, and due to the increased pressure of the air in the atomizing nozzle, the pressurized air flows from the atomizing nozzle into the cooling water pipeline. As a result, the present inventors have found that water remaining in the cooling water pipe becomes backflow water and is returned to a water supply tank or the like, thereby completing the present invention.

More specifically, the operation control device for a cooling tower according to the present invention is a tower incorporated in a sticky fume removing device, in which a cooling water atomizing nozzle is provided around an inlet of a fume-containing gas. A cooling tower provided with a water supply means and an air supply means which are connected to the atomizing nozzle by pipes so as to supply cooling water and pressurized air to the atomizing nozzle from below the cooling tower. An apparatus for controlling operation, comprising two temperature detecting means provided in an upstream area where fume-containing gas is introduced into the cooling tower and a downstream area where the fume-containing gas is fed from the cooling tower to the filter section. A control circuit connected to the two temperature detecting means, wherein when the adhesive fume removing device is operated, when the temperature detected by the upstream temperature detecting means exceeds a predetermined temperature, the water supply means and the air supply The operation of the means is started, and thereafter, the supply of cooling water to the atomizing nozzle is controlled so that the temperature detected by the temperature detection means in the downstream region is maintained at a constant temperature, and the operation is terminated. An operation control circuit programmed to delay the stop of the operation of the air supply means for some time longer than that of the water supply means, and to continue the supply of the pressurized air after the end of the supply of the cooling water; Further, there is provided a water discharging means connected to a water pipe connecting the water supply means and the atomizing nozzle for discharging residual water in the cooling water pipe.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The adhesive fume removing apparatus used in the present invention has a fume-containing gas containing a cooling tower, a filter section, a blower, and a mist separation tower (mist separator).
Are arranged in this order. The filter unit uses the inertial collision effect to convert the sticky fume microparticles, which are mostly 1 micron or less, into large particles and re-scatter. Filters include
A non-woven mat in which single fibers are randomly distributed, as disclosed in the above publication, is used. The filter is periodically replaced by an exchange mechanism such as a conveyor. The blower uses the large suction force to force the sticky fume-containing gas introduced into the cooling tower to pass through the flow path of the device at a high speed, enabling high-speed filtration with the above-mentioned filter, thereby achieving an inertial collision effect. Can be optimized. The mist separation tower has a demister therein to collect large fumes re-scattered from the filter. A drain tank is preferably provided for collecting collected fumes, and a silencer is preferably provided for silencing. The cooling tower is inside it (usually at the bottom of the tower)
In addition, an appropriate number of cooling water atomizers, usually cylindrical devices, are arranged around the fume-containing gas inlet. The atomizing device is provided with an atomizing nozzle attached to the tip thereof, and a cooling water pipe and a pressurized air pipe connected to the atomizing nozzle, respectively, in the cylindrical apparatus main body. A mist is blown out to cool the fume-containing gas and make gas-liquid contact.
The atomizing nozzle generally includes a nozzle chamber to which both cooling water and pressurized air can be supplied, and a plurality of nozzle holes that communicate with the outside air. According to the present invention, only the pressurized air is used in the nozzle chamber. When the air is supplied to the nozzle, the pressure of the air in the nozzle chamber increases, and the atomization nozzle having a structure in which pressurized air can flow from the atomization nozzle into the cooling water pipe due to the increase in the pressure can be applied. The cooling water piping in each atomizer passes under the cooling tower and is collected into one pipe, led out to the lower side of the cooling tower, and finally supplied with water supply means (water supply pump and (Including a water supply tank). In addition, the piping of the pressurized air in each atomizing device passes under the cooling tower, and is integrated into one pipe, led out to the lower side of the cooling tower, and finally pressurized air. And a pipe connection with a supply means (supply source). An electromagnetic switching valve for performing a switching operation of the air supply is usually connected to the pressurized air supply pipe. As the pressurized air supply means, an air compressor can be used instead of the pressurized air pipe in the factory.

An operation control device for a cooling tower according to the present invention comprises two temperature detecting means, an operation control circuit connected to these means, and a water discharging means for discharging residual water in a cooling water pipe. Is provided. One of the temperature detecting means is provided in an upstream area where the fume-containing gas is introduced into the cooling tower, and the other of the temperature detecting means is the cooled fume-containing gas is fed from the cooling tower to the filter section. Downstream, more preferably in a basin immediately before the filter. The temperature detecting means includes a thermometer, a temperature sensor, and the like, and has a function of transmitting detected temperature information to the operation control circuit by an electric signal. The operation control circuit is connected to the water supply means (water supply pump) and the air supply means (electromagnetic switching valve for pressurized air), and performs at least the following operations when the adhesive fume removing device is operated. Is a control circuit programmed in advance. The detailed configuration of this control circuit is arbitrary. An output signal is sent to the water supply means and the air supply means when the temperature detected by the temperature detection means in the upstream region exceeds a predetermined temperature, for example, 55 ° C., for the first time at the beginning of the operation of the present apparatus. , Start driving them. After the start of the operation, the supply of the cooling water to the atomizing nozzle is controlled so that the temperature detected by the temperature detecting means in the downstream region is maintained at a constant temperature, for example, 50 ° C. ± 3 ° C. That is, when the detected temperature exceeds the upper limit temperature, the operation of the water supply means is restarted or the operating state is raised, and when the detected temperature falls below the lower limit temperature, the operation of the water supply means is stopped. Generally, sequence control or the like is employed. At the end of the operation of the present apparatus, for example, by a timer control, for some time than when the operation of the water supply means is stopped,
Normally, the operation of the air supply means is stopped with a delay of about 3 to 10 seconds (that is, the electromagnetic switching valve of the pressurized air is closed), and the supply of the pressurized air is continued even after the supply of the cooling water is completed. The water discharge means is suitable for discharging, for example, residual water in the water pipe to the water pipe (cooling water pipe) connecting the water supply means and the atomizing nozzle to the outside or returning the water to the water supply tank. Connected in configuration. The water discharge means generally comprises a combination of a discharge pipe and an on-off valve. For example, when the cooling water is conveyed from the water supply tank to the atomization nozzle via the water supply pump, the discharge pipe branches off from the pipe between the water supply pump and the atomization nozzle and is guided into the water supply tank. That is, a circulation system including a water supply pump and a water supply tank is formed, and provided in a mode that constitutes a part of the circulation system.The on-off valve is provided in the circulation system, for example, in a pipe from the water supply pump to the atomizing nozzle. Alternatively, it is connected to a discharge pipe branched from the pipe. The on-off valve may be a valve having a function of controlling the amount of water supplied from the water supply means to the atomizing nozzle. Further, in the apparatus of the present invention, when the operation control circuit performs the above operation, the water discharge means is also operated at the same time, that is, the on-off valve is opened. Therefore, when the operation of the water supply means is stopped, only the pressurized air is supplied to the inside of the atomizing nozzle from that time, and the pressurized air is supplied from the atomizing nozzle by the increased pressure of the air in the atomizing nozzle. Of the cooling water, and the water remaining in the cooling water is returned as backflow water.
Then, the water is discharged out of the discharge pipe of the water discharge means, for example, or collected in a water supply tank.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the adhesive fume removing device comprises a cooling tower 1, a filter section 2, a blower fan 3 and a mist separator 4, and the adhesive fume-containing gas introduced by the operation of the blower fan 3. Passes through each element at a high speed in a flow indicated by an arrow f. During the passage of the fume-containing gas, in the cooling tower 1, when the fume-containing gas is at a high temperature, the atomizing device 5.
・ More cooling water is sprayed in mist. The ejection of the mist and the gas-liquid contact promote liquefaction and aggregation of the organic substance in the fume-containing gas. The cooling tower 1 incorporates an operation unit including the operation control device of the embodiment, as described below. In the filter section 2, when the fume-containing gas passes through the filter 6, the fume microparticles (including the liquefied and aggregated organic substance) in the gas become larger particles and re-scatter. The filter 6 is made of a single-fiber non-woven mat, and is provided with an exchange mechanism 7 such as a conveyor so that the used filter 6 can be sequentially exchanged for a new filter 6. Further, in the mist separator 4, the re-scattered fume particles are collected and removed. A drain tank 8 is provided for collecting the collected fume, and a silencer 9 is provided for silencing.

As shown in FIGS. 2 and 3, the cooling tower 1 is provided with six cylindrical atomizers 5... Symmetrically around the gas inlet 11 at the lower part of the tower. The symbols in FIG. 3 or the respective locations of the atomizing devices 5 and the water or air pipes corresponding to the respective atomizing devices 5 are shown. Each of the atomizing devices 5 has its lower part protruding from the lower surface of the cooling tower 1 and the atomizing nozzle 10 at the tip.
Are installed at an angle so as to face the gas inlet 11 (see FIG. 2). In the atomizing device 5, the water pipe 12 and the air pipe 13 are connected to the atomizing nozzle 10 at the tip through the inside of the device body 14 from the base at the lower end. On the other hand, the cooling water hose 15 and the air hose 16 connected to these pipes 12 and 13 pass under the cooling tower 1 and are integrated into one pipe as shown in FIGS. And finally connected to the operating unit 17 respectively. The operation unit 17 includes a water supply pump 18 and a water supply tank 19, as shown in FIGS.
There is provided a discharge pipe 30 which is branched from the pipe toward the atomization device 5 and is guided to the water supply tank 19, and one circulation system is formed. The operating unit 17 is provided with a pipe 20 from a supply source of pressurized air. The cooling water hose 15 is connected to the water circulation system,
The air hose 16 is connected to the pressurized air pipe 20 together with the electromagnetic switching valve 21. The discharge pipe 30 is provided with a control valve 31 for adjusting the amount of water supplied from the water supply pump 18 to the atomizing device 5 (atomizing nozzle 10). That is, when the control valve 31 is slightly opened,
The amount of water supplied to the atomizing nozzle 10 decreases, and conversely, if the control valve 31 is operated to be slightly closed, the amount of water supplied to the atomizing nozzle 10 increases. That is, if the amount of water supplied to the atomizing nozzle 10 is reduced, the cooling of the fume-containing gas is weakened.
As the water supply to the furnace increases, the cooling of the fume-containing gas increases. In order to adjust the amount of water supplied to the atomizing nozzles 10,..., The water supply pump 18 itself may be controlled by an inverter. When the control valve 31 is completely opened, the residual water in the cooling water pipes 12 and 15 flows backward from the atomizing nozzle 10 toward the water supply pump 18 and enters the water supply tank 19 via the discharge pipe 30. It has a configuration that can be transported back. In short, in the present embodiment, in order to discharge the water remaining in the cooling water pipes 12 and 15 connecting each of the atomizing nozzles 10 of the six atomizing devices 5 and the water supply pump 18, a discharge pipe 30 is provided. A water discharging means including a combination of the control valves 31 is provided. The atomizing nozzle 10 is
As shown in FIG. 5, the nozzle body 22 is screwed onto the nozzle base 23, the cap 24 with the fine hole is placed thereon, and the cap 24 is attached to the nozzle body 2 by the retainer ring 25.
2 and a water passage in the center of the nozzle and an air passage around it, so that when cooling water and pressurized air are supplied to those passages, Flows into the nozzle chamber together, and is subsequently ejected from a plurality of nozzle holes, whereby water is atomized and sprayed into the cooling tower 1.

In this embodiment, as shown in FIG.
One temperature detecting means (temperature sensor) 26 is provided in an upstream region where the fume-containing gas is introduced into the cooling tower 1, and another temperature detecting means 27 is used for cooling the fume-containing gas from the cooling tower 1. The filter is provided in a downstream area fed to the filter unit 2, that is, in a basin immediately before the filter 6. Each of the temperature detecting means 26 and 27 outputs the detected temperature information in the form of an electric signal. Therefore, the output signal is sent to the operation control circuit in the operation unit 17.

The operation unit 17 includes a water supply pump 18, a water supply tank 19, a pressurized air pipe 20, and the like, but also a circuit (not shown) for controlling the operation of these water supply means and air supply means, ie, an operation. A control circuit is provided. This operation control circuit is electrically connected to the water supply pump 18 and the electromagnetic switching valve 21 for pressurized air, respectively. The operation control circuit is programmed in advance to perform at least the following operations when the adhesive fume removing device is operated. When the temperature detected by the temperature detection means 26 in the upstream region exceeds, for example, 55 ° C. for the first time at the beginning of the operation of the present apparatus, an operation start signal is output, and the water supply pump 18 and the electromagnetic switching valve are output. Send to 21. This allows
At the same time as the operation of the pump 18 is started, the switching valve 21 is opened, and the cooling water and the pressurized air are supplied to each of the atomizing nozzles 10 of the six atomizing devices 5. Is discharged, and the fume-containing gas flowing out from the gas inlet 11 is cooled and gas-liquid contact is made. Thereafter, the supply of the cooling water to the atomizing nozzle 10 is controlled so that the temperature detected by the temperature detecting means 27 in the downstream region is maintained at a constant temperature of, for example, 50 ° C. ± 3 ° C. That is, when the detected temperature exceeds the upper limit temperature,
When the operation of the water supply pump 18 is restarted or its operating conditions are increased, while the detected temperature falls below the lower limit temperature, the operation of the water supply pump 18 is stopped (at the same time, the electromagnetic switching valve 21 is closed, Stop supplying pressurized air.) Therefore, at the end of the operation of the present apparatus, the operation of the water supply pump 18 is first stopped according to the timer control, and then,
The electromagnetic switching valve 21 is closed with a delay of about 4 seconds from the stop time, and the supply of pressurized air is stopped. Therefore, the supply of the pressurized air to the six atomizing nozzles 10 continues even after the supply of the cooling water is stopped for about 4 seconds. In the present apparatus, when the operation control circuit performs this operation, the control valve 31 is completely opened at the same time.

In short, in the present embodiment, in addition to the water discharging means 30 and 31, two temperature detecting means 26 and 27 are provided.
And an operation control device comprising an operation control circuit for performing a program operation based on temperature information from these means. Thus, by such operation control, the device of the present embodiment was able to improve very good fume collection performance. In the present apparatus, when the operation control circuit performs the above operation, the control valve 31 is completely opened at the same time. Therefore, when the operation of the water supply pump 18 is stopped, only the pressurized air is supplied to the inside of each atomizing nozzle 10 from that time, and the air is increased by the increased pressure of the air in the atomizing nozzle 10. Water pipe 1 from 10
2 and into the cooling water hose 15, whereby
The water remaining in these cooling water pipes is returned as backflow water, and is recovered from the discharge pipe 30 to the water supply tank 19. Therefore, in this device, the cooling water is maintained at 6 even after the operation is completed.
Does not remain in the water line between the individual atomizing nozzles 10 and the water supply pump 18, that is, in the water pipe 12 and the cooling water hose 15. Therefore, there is no danger of the water pipe being damaged or broken due to freezing of the residual water.

[0016]

As described above, according to the cooling tower operation control device of the present invention, the operation of the cooling tower of the sticky fume removing device can be controlled under optimum conditions.
Even in the winter season when the operation of this apparatus is stopped, there is obtained an effect that the cooling water supply means is not damaged or broken due to freezing of the water pipe to the atomizing nozzle.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a sticky fume removing device in which an operation control device according to an embodiment of the present invention is incorporated.

FIG. 2 is a view showing the vicinity of a lower portion of a cooling tower in the adhesive fume removing apparatus of FIG.

FIG. 3 is a view showing a piping configuration of a cooling water pipe and a pressurized air pipe in the cooling tower shown in FIG. 2;

4 is a diagram showing the operation control device of the cooling tower shown in FIG. 2 in more detail.

FIG. 5 is an enlarged sectional view showing the inside of the atomizing nozzle shown in FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cooling tower 2 Filter part 3 Blower fan 4 Mist separator 5 Atomizer 10 Atomizing nozzle 12 Water pipe 13 Air pipe 15 Cooling water hose 16 Air hose 17 Operating unit 18 Water supply pump 19 Water supply tank 20 Pressurized air pipe 21 Electromagnetic switching valve 26 temperature detecting means 27 temperature detecting means 30 discharge pipe 31 control valve

Claims (1)

[Claims] 1. A cooling tower having a cooling water atomizing nozzle provided around an inlet of a fume-containing gas therein, wherein the cooling water and pressurized air are supplied to the tower incorporated in the sticky fume removing device. A device for controlling the operation of a water supply means and an air supply means which are respectively connected to the atomizing nozzle by a pipe so as to supply the atomizing nozzle from below the cooling tower, wherein the fume-containing gas is supplied to the cooling tower. Two temperature detecting means provided respectively in an upstream area introduced into the inside and a downstream area fed from the cooling tower to the filter section, and a control circuit connected to the two temperature detecting means,
During operation of the adhesive fume removal device, when the temperature detected by the temperature detection means in the upstream region exceeds a predetermined temperature,
The operation of the water supply means and the air supply means is started, and thereafter, the supply of the cooling water to the atomizing nozzle is controlled so that the temperature detected by the temperature detection means in the downstream region is maintained at a constant temperature. And, at the end of operation, the operation of the air supply means is programmed to be delayed for some time longer than that of the water supply means so that the supply of pressurized air is continued even after the supply of cooling water is completed. An operation control circuit, and a water discharging means connected to a water pipe connecting the water supply means and the atomizing nozzle, for discharging residual water in the cooling water pipe. , Cooling tower operation control device.