JP2001198490A - Cyclone type oil mist removing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently separate oil mist contained in air. SOLUTION: A water spray nozzle 19 is provided in the air introducing cylinder 14 of a cyclone 1 in the direction reverse to an air flow and a water spray nozzle 20 is provided to the outer periphery of an inner cylinder 16 in the same direction as the air flow while a downward water spray nozzle 21 is provided in an outer cylinder 11. By this constitution, oil mist in air entering the introducing cylinder 14 is collected by the sprayed water from the water spray nozzle 19 to become large in diameter and the separation of oil mist in the cyclone 2 becomes easy. Wave suppressing plates 25, 26 slightly protruding from the surface L of water are provided in an outflow cylinder 13 provided to the lower end of a removing device 3 and scattering preventing plates 28, 29 are provided above the plates 25, 26 to constitute a scattering preventing deivice 24 and the lower end of the outflow cylinder 13 is sealed with the water in a lower water tank 5. By this constitution, the water mixed with oil in the outflow cylinder 13 is suppressed in its movement by the scattering preventing device 24 even if scattered by the revolving air streams of the cyclone 2 to be ready to be re-mixed with air and prevented from scattering.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an oil mist generated from cutting oil in a manufacturing process such as machining or casting,
The present invention relates to a device for introducing air containing oil mist or the like generated from a solid material of foundry sand into a cyclone to remove oil from the air.

[0002]

2. Description of the Related Art As a means for removing oil contained in air, for example, a technique disclosed in Japanese Patent Application Laid-Open No. 11-5009 is known. This technology relates to the application of the present applicant, and sprays water into the processing air while swirling the processing air containing oil mist in a cyclone, and collects oil particles into water particles by centrifugal force. Spray and adhere to the inner peripheral surface of the outer cylinder, let it flow down into the lower water tank along the inner peripheral surface, adsorb oil to the adsorbent in the lower water tank, separate water, and spray the separated water Therefore, the air sucked from the inner cylinder at the center of the cyclone is further purified by the next cyclone and returned to the chamber having the oil mist generation source. Then, the adsorbent that has adsorbed a large amount of oil is replaced with a new one.

[0003]

According to the above-mentioned prior art, the stored water that has flowed down to the lower water tank is sprayed and swirled by the swirling airflow in the cyclone to form a mist, and the air containing the mist is removed from the cyclone. It is conceivable that the oil is circulated inside or sucked into the secondary cyclone to reduce the oil removal efficiency, and there is room for improvement in that the replacement of the adsorbent requires labor and cost. An object of the present invention is to improve these points to increase oil removal efficiency and facilitate maintenance.

[0004]

Means for solving the above-mentioned problems are, as described in claim 1, a main body having an outer cylinder, a tapered cylinder, and an outflow cylinder connected from the top, and an upper part in the main body. An inner cylinder provided concentrically with the outer cylinder, an air introduction cylinder tangentially connected to the outer cylinder, a lower water tank for water sealing the outflow cylinder, and introducing air containing oil mist from the air introduction cylinder to the main body, A cyclone-type oil mist removal device that rotates inside the main body while spraying water spray on the air, sucks the air separated from the oil mist from the inner cylinder, and flows the mixed water in which the oil mist is aggregated from the outflow cylinder to the lower water tank. In the inside of the outflow cylinder, a surge suppression plate is provided that is exposed upward from a water surface position that rises during operation of the apparatus and extends in a direction crossing the stored water inside the overflow cylinder, and inside the overflow cylinder above the surge suppression plate. The outflow cylinder A small diameter anti-scattering plate is provided horizontally.

According to this means, the stored water in the outflow cylinder is
It can be prevented from being mist again and circulating in the cyclone or being sucked into the secondary cyclone.

According to a second aspect of the present invention, in the first aspect, a water spray nozzle for spraying water toward an air flow is provided in the air introduction cylinder. According to this means,
Oil particles in the air flow are trapped by water particles coming out of the water spray nozzle and become large-diameter particles.Therefore, after entering the cyclone, they are more easily captured by water particles from the internal water spray nozzle, Removal efficiency is improved.

[0007] The means of claim 3 is characterized in that, in claim 1, an inlet of an oil-water discharge pipe is arranged near the water surface of the lower water tank and communicates with the oil-water separator, and a water spray nozzle is provided near the bottom of the lower water tank. Characterized in that an inlet of a pipe for sending water to the water is disposed. According to this means, water can be reused without using an oil adsorbent.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a factory having a manufacturing process for generating an oil mist and releasing the oil mist into the indoor air. For example, a factory for performing a cutting process using a cutting oil or a casting using an oil mixed with molding sand is used. Such as factories. 2 is a primary cyclone that separates oil mist from the air first, 3 is a secondary cyclone that separates oil mist for the second time, 4 is an intake fan that sucks air from both cyclones 2, 3 and 5 is a lower water tank. A water pump 6, a circulating water purification system pump 7, an oil / water separator 8 installed outside the water circulation system connecting the lower tank 5 with the primary and secondary cyclones, and an oil recovery tank 9 are attached.

[0009] The primary cyclone 2 is an outer cylinder 1 in order from the top.
1, a vertical main body 10 including a tapered tube 12 and an outflow tube 13. An air introduction tube 14 is connected to the outer tube 11 in a tangential direction. 1
The inner cylinder 16 is installed concentrically over the upper part of the second 2, the air introduction cylinder 14 is connected to the factory 1 by a ventilation duct 17, and the inner cylinder 16 is connected to the secondary cyclone 3 by an air supply duct 18. I have.

As shown in FIG. 2, a plurality of water spray nozzles 19 are installed in the air introducing cylinder 14 so as to face the air flow of the processing air entering from the ventilation duct 17. As shown in FIG. 3, water spray nozzles 20 are provided in multiple stages, which spray in the same direction as the airflow swirling direction indicated by the arrow, and spray the inner surface of the main body 10 along the inner surface as shown in FIG. 4. The water spray nozzle 21 is installed downward, and the water in the lower water tank 5 is supplied to each water spray nozzle by the water pump 6 and the pipes 22 and 23.

The water spray nozzle 19 in the air introduction cylinder 14
Is for increasing the diameter of the oil mist before introducing the air discharged from the factory into the main body portion 10. As shown in FIG. 2, the oil mist particles m in the processing air are The water S sprayed from the water spray nozzle 19 collides with the water particles of the spray S and is trapped, becomes mist particles M having a diameter larger than the oil mist particles m, flows into the main body 10, and is provided around the inner cylinder 16. The diameter of the spray water droplets from the spray nozzle 20 further increases the diameter of the water droplets, and the water particles are more likely to be caught. The water particles collide with the inner surface of the tapered cylinder 10 with a large inertial force and are easily caught and flow down.

The water spray nozzle 21 makes large-diameter water droplets including oil mist adhering to the inner wall of the main body 10 flow down into a thin water film, but catches the oil mist still in the airflow by downward spraying. Thus, the inner surface can flow down. Therefore, by providing the water spray nozzle 19, the small diameter oil mist particles m
The oil mist removal efficiency of the entire removal device is improved as compared with the case where the oil mist is contained. The average water particle diameter of the spray from each water spray nozzle is 130 μm for the nozzle 19, 600 μm for the nozzle 20, and 600 μm for the nozzle 21.

By the way, since the inside of the cyclone is under negative pressure,
There is a concern that the stored water containing oil mist may re-spray, but the present inventors have solved the problem by the following means. That is, as shown in FIG. 5, in the outflow cylinder 13, there is provided a scattering prevention device 24 composed of anti-ripening plates 25, 26 and scattering prevention plates 28, 29. Among them, the ripple suppression plate 25
Are installed in a cross shape in the radial direction, and
Is installed in a square shape inscribed in the outflow tube 13,
It is fixed at a height slightly projecting upward from an inland surface L rising by a negative pressure in the main body portion 14. These ripple suppression plates 2
5 and 26 are provided in a direction crossing the swirling flow of the stored water at right angles and obliquely, thereby preventing the water in the outflow tube 13 from waving and suppressing mist formation.

Two scattering prevention plates 28 and 29 are fixed substantially parallel to the surface of the water at the intersection of the surge suppression plates 25, that is, at the column 27 standing at the center of the outflow cylinder 13. When the mist scatters, it collides with them to prevent the mist from rising further. Cyclone 2 processing air volume 100 m ³ / min, inner diameter D of outflow cylinder 13 = 550 m
m, height H = 9 from the outer water surface L0 to the upper end of the outflow cylinder 13
In the case of 50 mm, the lower anti-scattering plate 28 is provided at a position of h1 = 40 mm from the inner water surface L, and the upper anti-scattering plate 29 is located above the lower anti-scattering plate 28 by h2. Is given by h2 = (4
/ 9) H, and the diameter d of each scattering prevention plate is about d = (9/11) D with respect to the inner diameter D of the outflow tube 13.

FIG. 6 shows the effect of removing the oil mist of the cyclone provided with the scattering prevention device 24 shown in FIG. 5 in comparison with a conventional cyclone not provided with the scattering prevention device 24. Prevention device 24
The one provided with has a removal efficiency of 32.8%, which is more than twice the efficiency of 15.6% of the conventional structure.

The secondary cyclone 3 includes the primary cyclone 2
Is discharged by an air supply duct 18 to separate the remaining oil, flow it to the lower water tank 5 by a pipe 30, and return purified air to the factory 1 by a return duct 31. The oil in the stored water returned to the lower water tank 5 gradually separates from the water with a specific gravity difference, floats on the water surface, is sucked together with the water by a circulating water purification system pump 7 from an inlet of a pipe 32 arranged near the water surface, and is separated by an oil-water separator. The oil is sent to the lower tank 5 via a pipe 33 and the oil is sent to an oil recovery tank 9 via a pipe 34.

In the figure, reference numeral 35 denotes a water supply valve, which is controlled by a water level gauge 36 and a water level controller 37, and controls the outer water level L0 of the lower water tank 5. Reference numeral 38 denotes a heat source device provided with a heat pump for controlling the temperature of the circulating air. The heat source device 38 is connected to a heat exchanger 39 and a three-way valve 40 for controlling the flow of a heat medium.
, The temperature of the air passing through the ventilation duct 31 is measured, and the three-way valve 40 is adjusted by the temperature controller 42 to control the temperature to a required temperature.

As described above, the oil mist particles in the air flowing into the cyclone 2 from the factory 1
The particles sprayed from 9, 20, 21 increase the particle diameter while being collected one after another, flow down into the outflow tube 13, and enter the lower water tank 5. With the provision of the splash prevention device 24, the stored water in which the oil is mixed with the water is prevented from being turned into water droplets or mist again by the swirling airflow inside the outflow tube 13 and being rolled up. It can be sent to the secondary cyclone via the inner cylinder 16. Further, since the water stored in the lower water tank 5 is treated without using the oil adsorbent used in the above-described conventional technique in the lower water tank 5, the time and cost for replacing the oil adsorbent can be reduced, and the oil can be reduced. Separation equipment can be maintained outside the system.

In the above-described embodiment, the water jetting direction of the water spray nozzle 19 in the air introducing cylinder 14 is oblique to the air flow or follows the air flow in addition to the direction facing the air flow. It may be a direction. Note that, depending on the operating conditions of the cyclone, one of the ripple suppression plates 25, 26 may be omitted, or one of the scattering prevention plates 28, 29 may be omitted, or the number of plates may be increased or decreased.

[0020]

As is apparent from the above description, according to the first aspect of the present invention, the water containing the oil flowing into the outflow cylinder in the cyclone type oil mist removing device is waved by the ripple preventing plate of the scattering prevention device. Is prevented from being scattered in the air by the scattering prevention plate,
The effect that the oil mist removal efficiency is remarkably improved as compared with the one that does not include the scattering prevention device is provided. Moreover, the ripple suppression plate is only slightly exposed to the airflow from the inland water surface,
Since the scattering prevention plates are horizontal, there is an advantage that almost no hindrance of the airflow is hindered and no energy is lost.

According to the second aspect of the present invention, the oil mist particles in the processing air in the inlet pipe are trapped by the water particles of the spray coming out of the water spray nozzle and become larger particles than the oil mist particles. Since the gas flows into the main body, it is easy to catch the fuel by spraying the inside of the main body and the inner peripheral surface of the main body, thereby improving the oil mist removal efficiency.

According to the means of claim 3, there is an advantage that the oil and water are separated without using an adsorbent, so that handling is easy.

[Brief description of the drawings]

FIG. 1 is a layout diagram of each element showing an embodiment of the present invention.

FIG. 2 is an explanatory view of an operation inside an air introducing cylinder.

FIG. 3 is a cross-sectional view of the inner cylinder.

FIG. 4 is a longitudinal sectional view of an outer cylinder.

FIGS. 5A and 5B show an outflow cylinder, wherein FIG.

FIG. 6 is a graph showing the effect of the scattering prevention device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Factory 2 Primary cyclone 3 Secondary cyclone 4 Intake fan 5 Lower water tank 6 Oil-water separator 10 Main body 11 Outer cylinder 13 Outflow cylinder 14 Air introduction cylinder 16 Inner cylinder 19, 20, 21 Water spray nozzle 24 Splash prevention device 25, 26 Rippling suppression plate 28, 29 Shatter prevention plate

Continued on the front page F-term (reference) 4D032 AA05 AC03 AC07 AC08 BA05 BB18 4D053 AA01 AB01 BA01 BB02 BC01 BD04 CA18 CB11 CD27 CD30 CE05 CG01

Claims (3)

[Claims] 1. A main body having an outer cylinder, a tapered cylinder, and an outflow cylinder connected to each other from an upper part, an inner cylinder provided concentrically at an upper part in the main body, and an air introduction cylinder tangentially connected to the outer cylinder. A lower water tank for water-sealing the outflow cylinder is provided, air containing oil mist is introduced into the main body from the air introduction cylinder, and the air is swirled in the main body while spraying water onto the air to separate the air from which the oil mist is separated. In a cyclone type oil mist removal device which sucks the oil mist from the inner cylinder and causes the mixed water in which the oil mist is aggregated to flow out of the outflow cylinder to the lower water tank, the cyclone type oil mist is exposed inside the outflow cylinder from the water surface position which rises when the device is operated and flows out. Provide a ripple suppression plate that extends in the direction across the stored water inside the cylinder,
A cyclone type oil mist removing device, wherein a scattering prevention plate having a smaller diameter than the outflow tube is provided horizontally above the surge suppression plate inside the outflow tube. 2. The cyclone type oil mist removing device according to claim 1, wherein a water spray nozzle for spraying water toward an air flow is provided in the air introducing cylinder. 3. An oil-water separator according to claim 1, wherein an inlet of an oil-water discharge pipe is arranged near the water surface of the lower water tank to communicate with the oil-water separator, and water is sent to the water spray nozzle near the bottom of the lower water tank. A cyclone-type oil mist removing device, wherein an inlet of a pipe is arranged.