JPH115009A - Oil mist removing and ventilating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the capturing efficiency of oil mist and to facilitate the equipment control for the removal of the captured oil component by separating the oil component from a waste water by an oil-water separation means in a water tank storing water containing the oil mist, which is discharged from a gas-liquid contact device. SOLUTION: At least one cylinder shaped dam 17 having lower height than the water level is provided in the water tank. A water suction pipe as a water intake port 13 of a pipe line 16 is arranged outside of the dam 17 and an oil adsorbing coagulant 18 for adsorbing and coagulating the oil component from a spray water containing the oil mist is floated and arranged on the water surface to cover the water suction pipe. The oil adsorbing coagulant 18 is hydrophobic and is a granular body formed from, for example, a hydrocarbon polymer and additives, which is packed in a cotton cloth-made or chemical fiber-made bag and formed into two pieces of semiannular mat form or film form to easily detach at the time of changing and to facilitate the maintenance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an oil mist removing and ventilating apparatus for controlling an air environment in, for example, a machine factory that generates oil mist.

[0002]

2. Description of the Related Art For example, cutting oil used for cutting and precision machining of metal materials and the like in a machining factory and a precision machine factory, and oil mist generated from a solid material of a foundry sand used in a foundry factory, as it is, impair the health of workers. Cause Also, depending on its concentration, it smokes pale or milky white, which reduces the line-of-sight distance, which is a factor that impairs work safety and product quality.
In these factories, the cutting oil has been cooled so that oil mist is less likely to be generated, and the generated oil mist has been collected and removed by a local exhaust device near the generation source. Although it could not be collected and partly adhered to walls and the like, part was released into the space and diffused throughout the manufacturing process in the factory, and the accumulated concentration was maintained.

[0003] Therefore, conventionally, as an oil mist removing and ventilating apparatus, a) a collision type demister or filter, b) an air flow which repeats expansion and contraction of air is formed to promote the coagulation of the oil mist and reduce the particle size. A mechanical trapping mechanism for increasing the trapping efficiency by increasing the adhesion, c) a scrubber widely known as a gas absorption tower, and the like are used.

[0004]

The demister of the device described in the above-mentioned conventional a) has a trapping efficiency of about 60%,
A medium-performance filter has a capture efficiency of about 99%,
Since the pressure loss increases sharply, its life is short, and it is a disposable type, it has the drawback that the fan power cost increases, it takes time for equipment management such as filter replacement, and the cost is high. However, there is a disadvantage that a high trapping efficiency cannot be expected, and the device of c) has a built-in filler, and when applied to the removal of oil mist, an oil component adheres to the filler, so that the filling of the filler is reduced. There is a drawback in that it takes time and effort to perform equipment management such as cleaning and the management cost is high, and there is a drawback in that the apparatus configuration becomes complicated and the cost increases.

The present invention solves the above-mentioned drawbacks of the oil mist removing ventilator, and can expect a high efficiency of capturing the oil mist of the indoor air, and can easily manage the equipment for removing the captured oil mist, and can reduce the facility management cost. Is also cheap,
An object of the present invention is to provide an oil mist removing and ventilating device that can be used by circulating indoor air.

[0006]

In order to solve the above-mentioned problems, the present invention is an apparatus for purifying air containing oil mist, wherein water is sprayed on air to be treated. A gas-liquid contact device provided with a nozzle for performing the operation, a water tank for storing water containing oil mist discharged from the gas-liquid contact device, an oil-water separating means provided in the water tank, and water taken from the water tank. Water circulation means for circulating through the nozzle, and forced air circulation means for guiding air containing oil mist from the room to the gas-liquid contact device and returning the air passing through the gas-liquid contact device to the room again. . The outlet of the water containing the oil mist of the gas-liquid contact device is immersed in the water of the water tank to prevent air other than the air excluding the oil component from entering. The oil-water separating means is preferably an oil adsorbing / coagulating means floating on the water surface of a water tank in terms of facility management. In the water tank, the flow of water is brought into a still water state and the oil component is collected therein. A weir having a height lower than the water level may be provided, and an intake of the water circulating means may be provided at a position passing through at least one weir from the outlet to continuously spray water in the tank from a nozzle. Desirably, furthermore, a water level sensor in the tank of the water tank, and a water supply means for introducing makeup water into the water tank when the water level sensor detects a decrease in the water level, to reduce the water level due to evaporation of spray water or the like. It is desirable to prevent it automatically. The water circulation means refers to a water circulation system downstream of the water tank and upstream of the spray nozzle in the cyclone,
In addition to the piping for conveying water, power means such as a pump and flow rate adjusting means such as a valve are used as constituent elements as necessary.

According to the structure of the first aspect of the present invention, in the oil mist removing and ventilating apparatus for improving the indoor air environment, the water tank for storing the water containing the oil mist discharged from the gas-liquid contact device is provided. The oil component is separated from the wastewater by the oil / water separation means, which makes it easy to manage the equipment for removing oil mist and circulates and reuses the water in the tank from which oil mist has been removed to the gas-liquid contact device, making it economical. It is.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of an oil mist removing and ventilating apparatus according to the present invention will be described with reference to the drawings.

In the drawings, reference numeral 1 denotes a chamber in which a manufacturing process (not shown) for generating oil mist is performed in, for example, a machine factory, reference numeral 2 denotes a cyclone, and reference numeral 3 denotes a heat source device such as a heat pump. The cyclone 1 has an air inlet 4
a has a discharge port 4b at a lower part, and an outer cylinder 4 having a lower part formed in a funnel shape, a lower part being disposed in the outer cylinder 4, having a lower end opening into the outer cylinder 4, and an upper part forming an exhaust port 5a. Exhaust pipe 5,
The exhaust pipe 5 includes a plurality of spray nozzles 6 arranged close to the outer periphery of the exhaust pipe 5 and a plurality of spray nozzles 7 arranged almost uniformly in the vicinity of the outer cylinder 4. The air inlet 4a of the cyclone 2 is connected to the chamber 1 by a duct 8a, and the exhaust port 5a is connected to the chamber 1 by a duct 8b via a secondary cyclone 9 or a demister and a suction fan 10. Cyclone 2 and secondary cyclone 9
Or an air pipe or duct 8b between the cyclone 2 and the secondary cyclone 9 or the demister, and a pipe or duct 8 between the secondary cyclone 9 or the demister and the chamber 1
b is sufficiently insulated.

The outlet 4b of the cyclone 2 and the outlet of the secondary cyclone 9 or the demister are immersed in the water 12 in the water tank 11, and the plurality of spray nozzles 6 and 7 serve as water circulating means, and the water intake 13 is provided in the tank. Immersed in water 12 and pump 14
And an adjustment valve 15 are connected to a pipe 16 which is connected by an intervention. Although not shown, the pipe 16 is introduced into the cyclone 2 and is wound along the inner wall of the outer cylinder 4 and the outer wall of the exhaust pipe 5 or extends downward from above to be connected to the plurality of spray nozzles 6 and 7. You.

As shown in FIG. 2, the spray nozzle 6 is arranged in the same tangential direction as the airflow swirling direction of the air introduced into the cyclone 2 (indicated by an arrow). As shown in FIG.
As shown in FIG. 2A, they are distributed over the entire circumference of the inner wall surface in such a direction as to form a thin water film on the inner wall of the outer cylinder 4.

As shown in FIG. 4, the water tank 11 is provided with at least one cylindrical weir 17 having a height lower than the water surface. This is because the tank water 12 discharged from the cyclone 2 is kept in a still water state, and the water and oil mist are mixed violently on the inside, while the oil component and water are separated on the outside, and the water is uniformly distributed upward. In order to suspend the oil component and prevent the water pipe 13 from sucking dust and the like, the inside of the cyclone is negative pressure by the fan 10 during operation and the water level in the outlet 4b is higher than the water level of the water tank 11 during operation. When the operation is stopped, the water tank 11 in the discharge port 4b is
This is for preventing the water above the water surface from dropping and spreading over the entire water tank 11. Outside the weir 17, for example, a water intake pipe 13 </ b> A as the water intake 13 of the pipe 16 is arranged, and the oil component is adsorbed from the spray water containing oil mist and solidified on the water surface so as to cover the water intake pipe 13 </ b> A. An oil adsorbent / coagulant 18 is suspended and arranged.
The water absorption pipe 13A is provided on the bottom of the water tank 11 outside the weir 17 and has a cylindrical structure having a large number of punching holes. By having a large number of small holes, the total suction surface area is large. As a result, the suction speed can be suppressed to a low level, the oil droplets are prevented from being sucked, and the state of oil-water separation can be reliably maintained. The oil adsorbent / coagulant 18 is hydrophobic and capable of adsorbing and coagulating oil of about 5 times its own weight. For example, granules made of a hydrocarbon polymer and additives (for example, a trademark of HAZ-MAT, USA) This is, for example, two semi-annular mats or membranes formed by filling a cloth bag made of cotton cloth or chemical fiber, and is formed into two semi-annular rings. It is easy to remove when replacing and maintenance is easy.

The water level of the water 12 in the water tank 11 is detected by a water level detector 19a. The water level controller 19 connects one end to a water supply source (not shown) and the other end to a conduit 20 opening to the water tank 11. The intervening three-way valve 21 is configured to be maintained at a predetermined level by controlling it.

The heat source equipment, for example, the heat pump 3
1 heats or cools the water 12 in the water tank 11 by the heat exchanger 3a placed in the water in the water tank. The amount of heating or cooling is determined by the three-way inserted into the pipe 22 to the heat exchanger 3a. It can be changed by controlling the amount of water by controlling the valve 23 or the output capacity of the heat pump body. In the example shown,
The temperature of the air returned from the cyclone 2 to the room via the secondary cyclone 9 or the demister and the suction type fan 10 is detected by the temperature sensor 24a inserted in the duct 8b, and the three-way valve 23 is controlled by the temperature controller 24. The water 12 in the tank is controlled to a predetermined temperature.

In the ventilator, the oil component of the spray water discharged from the cyclone 2 is removed by using the oil adsorbing / coagulant 18, but an oil filter may be provided in the pipe line, or Various oil-water separation means can be used, such as diluting with city water after discarding a part, or separating oil components from wastewater vaporized.

In FIG. 1, reference numeral 15a denotes a pressure gauge provided in a pipe 16. When this pressure gauge is used, the adjusting valve 15 is replaced with an electric two-way valve, and when the pressure gauge 15a detects an increase in pressure, the electric two-way valve is used. Even if the opening degree of the valve is increased and the opening degree is fully opened, if the pressure is still higher than the set pressure, a controller (not shown) for increasing the capacity of the pump 14 and operating the pump 14 is provided.

Next, the operation of the oil mist removing and ventilating apparatus will be described.

The air containing oil mist generated in the chamber 1 is introduced into the cyclone 2 from the air inlet 4a via the duct 8a by the suction fan 10, and swirls in the outer cylinder 4. Spraying of water by the spray nozzles 6 arranged in the same direction as the air flow swirling direction of the air (indicated by the arrow) and tangentially does not hinder the swirling flow of the air and further actively promotes the spraying. The fine water droplets caused by the spray not only capture the oil mist, but also move the oil mist to the inner wall of the outer cylinder 4 more. The oil mist adhering to the inner wall and the water droplets containing the oil mist flow down by spraying water with the spray nozzle 7 and flowing down a continuous thin water film formed on the inner wall surface of the outer cylinder 4. Is efficiently removed from the cyclone 2. The spray water containing the oil mist discharged from the outlet 4b of the cyclone 2 is stored in the water tank 11, and the oil mist is
Absorbed and coagulated by oil adsorbent / coagulant 18 and water 12 in tank
And separated. The temperature of the water 12 in the tank is determined by a temperature sensor 24 inserted in the duct 8b.
The temperature is controlled to a predetermined temperature by controlling the three-way valve 23 inserted in the pipe 22 of the heat pump 3 by the temperature controller 24 which is detected by a. The water 12 in the tank controlled to a predetermined temperature in the water tank is sucked by the pump 14 from the water inlet 13, i.e., the water supply pipe 13 </ b> A, is sprayed from the spray nozzles 6 and 7, and is circulated. Thus, the air from which the oil mist has been removed is adjusted to a predetermined temperature by the spray water, and the air is discharged from the exhaust port 5a to the air pipe or duct 8 by the suction type pump 10.
b, discharged into the room via the secondary cyclone 9 or demister and the air pipe or duct 8b. The adjustment valve 15
Is adjusted to adjust the circulating water amount, or a pressure gauge 15a is provided in the pipe 16 as shown in the figure, the adjustment valve 15 is an electric two-way valve, and the nozzle water supply pressure is measured by the pressure gauge 15a. By automatically adjusting the opening of the electric two-way valve so that it can be maintained, the amount of water to be sprayed and the amount of processing air [the amount of processing air (the amount of air introduced into the cyclone and the amount of air supplied to the chamber) can be changed by the swirling flow. It is desirable that the thickness be constant for stable formation. ] Can be adjusted to adjust the oil mist removal efficiency. The pressure gauge 15 described above
a, a means constituted by an electric two-way valve, a controller and the like constitutes means for avoiding a situation in which the set water amount is not discharged from the spray nozzles 6 and 7 due to clogging of the spray nozzles 6 and 7 or a strainer (not shown). To do
If a pressure increase is detected while the pump 14 is operating at a constant flow rate, a signal is sent to a controller (not shown) to increase the opening of the electric two-way valve and to set the pressure even when the electric two-way valve is fully opened. If higher, the pump 14 is operated with increased capacity.

In the ventilator, the temperature of the water in the tank is adjusted and the secondary cyclone is used. However, the temperature may not be adjusted and the secondary cyclone may not be used. Further, a demister can be used instead of the cyclone.

[0020]

According to the present invention, it is possible to obtain a high efficiency of capturing the oil mist of the indoor air, and it is easy to manage the equipment for removing the captured oil component, and the equipment management cost is low.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an example of an oil mist removing and ventilating apparatus according to the present invention.

FIGS. 2A and 2B are a cut-away plan view of a cyclone discharge pipe and a spray nozzle, and a cut-away side view of a main part of the cyclone.

FIG. 3 is a sectional side view of an outer cylinder and a spray nozzle of a cyclone.

FIGS. 4A and 4B are a cross-sectional view and a plan view of a water tank.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Room 2 ... Cyclone 3 ... Heat pump 4 ... Outer cylinder 5 ... Exhaust pipe 6 ... Injection nozzle 7 ... Injection nozzle 8a, 8b ... Duct 10 ... Fan 11 ... Water tank 12 ... Tank water 14 ... Pump 15 ... Adjustment valve 16 ... Pipe 17 ... Weir 18 ... Oil absorption /
Coagulant 19: Water level controller 24: Temperature controller

Claims (7)

[Claims] 1. A device for purifying air containing oil mist, comprising: a gas-liquid contact device having a nozzle for spraying water to air to be treated; and a water containing oil mist discharged from the gas-liquid contact device. , An oil-water separator provided in the water tank, a water circulating means for circulating water taken from the water tank to the nozzle, and introducing air containing oil mist from a room to a gas-liquid contact device and A ventilator for removing oil mist, comprising: forced air circulation means for returning air that has passed through the gas-liquid contact device back to the room. 2. The oil / water separating means is oil absorbing / coagulating means floating on the surface of the water tank.
The described oil mist removal ventilator. 3. The oil mist removing and ventilating device according to claim 1, wherein the water tank is provided with a weir having a height lower than the water surface inside the water tank. 4. The discharge port of the gas-liquid contact device is immersed in water of a water tank, and the water intake port of the water circulation means is provided at a position passing through at least one weir from the discharge port. The described oil mist removal ventilator. 5. A tank according to claim 1, further comprising a water level sensor for detecting the water level in the water tank, and a water supply means for introducing makeup water into the water tank when the water level sensor detects a decrease in the water level. The ventilation device for removing oil mist according to any one of the above. 6. The oil mist removing and ventilating apparatus according to claim 1, further comprising a temperature adjusting means for adjusting the temperature of the water in the water tank. 7. The gas-liquid contact device according to claim 1, wherein the gas-liquid contact device is a cyclone that catches the oil mist with fine water droplets by spraying water with a nozzle on a swirling flow of air containing the oil mist. Oil mist removal ventilator.