JP2848509B2 - Suspended particulate capture device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for capturing mist-like suspended fine particles such as smoke generated from an incinerator.

[0002]

2. Description of the Related Art For capturing minute mist-like particles floating in a gas (air) such as smoke generated from an incinerator, for example, the fine particles are scattered as shown in FIG. 14 of Japanese Utility Model Application Laid-Open No. 1-69618. 2. Description of the Related Art There is known a filter and dust collecting apparatus for filtering with a filter as shown (a so-called bag filter). However, in this bag filter type filter dust collector, although the dust collection rate is high, the pressure loss is large, for example, 100 to 200 mmAq, and the particle size that can be captured is 20%.
~ 0.1μ, especially when capturing extremely small mist-like particles such as odors of 0.1μ or less, without using a large-sized electrostatic precipitator with high initial cost and running cost. There was a problem that did not become. Accordingly, a showering type washing tower (so-called jet scrubber) having a low initial cost and running cost as shown in FIG. 2 of JP-A-3-232514 is widely used.

[0003]

However, in the showering type washing tower described above, water is supplied in a shower form into a gas containing ultra-fine mist-like particles (hereinafter, simply referred to as a processing gas), and the shower is washed. There is a problem that a large amount of water is required in order to contact and capture the extremely fine mist-like particles in the processing gas with the water droplets.

Further, in a case where extremely small mist-like particles of a processing gas are brought into contact with and trapped by water supplied in a shower state, a so-called jet scrubber disclosed in Japanese Patent Application Laid-Open No. 3-232514 discloses a water jetted in a shower state. As a result, a flow is generated in the processing gas, so that the efficiency of contact with the processing gas deteriorates. In addition, when a shower water droplet is supplied into a stationary positive or normal pressure processing gas, the water droplet pushes away the processing gas and flies. In addition to the low contact efficiency between the particles and the water droplets, the water supplied in the form of a shower tends to cause a flow of the processing gas along the downward flow of the shower. Is caused to flow together with the shower, so that the fine mist-like particles in the processing gas do not come into contact with the shower water droplets satisfactorily, and the dust collection efficiency is greatly reduced. The present invention has been proposed in view of the above-described problems, and it is an object of the present invention to provide a device for capturing suspended particulates which can be made into a small-sized device, but can capture extremely small mist-like particles of a processing gas without leaving any space. It is the purpose.

[0005]

According to the present invention, there is provided a suspended particulate capturing apparatus comprising: a particulate capturing tube; a pressurizing pump for forming a pressurized fluid; and a high-pressure fluid supplied from the pressurizing pump. And a jet pump that forms a negative pressure by injecting the particles into the particle capturing tube.
A protective tube is provided concentrically with the fluid ejecting nozzle and the fluid ejecting nozzle in front of the fluid ejecting nozzle, and a pressurized fluid is ejected from the fluid ejecting nozzle into the protective tube to form a negative pressure in the protective tube, and is formed in the protective tube. A mixed jet that forms a negative pressure in the fine particle trapping tube by injecting air at the specified negative pressure to convert the fluid in the protective tube into a mixed jet flow, and injecting the mixed jet flow from the protective tube to the fine particle trapping tube. In addition to a pump, a suction chamber for taking out a negative pressure formed by the mixed jet pump is provided between the protective tube and the fine particle capturing tube to form a negative pressure forming means, and one end thereof is connected to the suction chamber. The other end of the suction tube is opened toward the gas containing the floating particles, the gas containing the floating particles is sucked into the particle capturing tube from the opening end, and the floating particles in the sucked gas are mixed with the jet stream. It was configured to contact and capture And it is characterized in and.

One of the features is that the discharge-side open end of the fine particle capturing tube is connected to a gas / liquid separator.

[0007]

First, a fluid such as water is pressurized by a pressurizing pump, and the pressurized fluid is jetted from a fluid jet nozzle toward a protective tube. When the high-pressure fluid injected into the protection tube flies in a granular form and spreads completely in the protection tube, a negative pressure is formed on the fluid ejection nozzle side of the protection tube. The outside air is sucked into the protection tube by this negative pressure, and the high-pressure fluid flowing through the protection tube is converted into an air-mixed jet and is linearly injected into the particle capturing tube.
When a plurality of mixed jets injected into the particle capturing tube fly in a granular form, a negative pressure is generated between the particles of the flying fluid and the surrounding gas to be stationary due to the velocity difference of Bernoulli's theorem At the same time, the front part of the fluid particles flying in the fine particle trap tube compresses and flows air.

Then, when the fluid particles form a negative pressure around the fluid particles, the fluid particles fly through the particle capturing tube while compressing the air at the front portion thereof, and when the particles are fully spread in the particle capturing tube, The negative pressures around the particles are fused together, and the combined negative pressure and the combined compressed air at the front surface of the particles combine to produce a discharge-side open end of the particle capturing tube. Acting like a continuous piston acting toward the part, a high pressure and a large amount of negative pressure are formed near the fluid ejection nozzle of the particle capturing tube. At this time, the momentum of the jet stream tends to attenuate due to the contact resistance between the mixed jet stream and the inside of the fine particle trapping tube, and the air or the processing gas contained in the mixed jet stream acts as a cushion to force the jet stream. Therefore, a strong negative pressure can be formed in the fine particle trapping tube.

When the negative pressures formed around the particles of the fluid fuse with each other and the compressed air in the front part of the particles is united, the negative pressure and the compressed air are adjacent to each other. Since the high-speed fluid is rapidly spread by acting on the flying particles, the distance from the fluid ejection nozzle to a position where the fluid is fully spread in the particle capturing tube is reduced. The processing gas is sucked into the suction chamber from the suction pipe while being metered by the flow rate adjusting means by the negative pressure thus formed. Here, when the processing gas is squeezed by the flow rate adjusting means, the squeezed processing gas is slowly sucked little by little, and the speed difference from the high-speed fluid ejected from the fluid ejection nozzle increases. According to Bernoulli's theorem, a negative pressure on the peripheral surface of the fluid to be transported is also strongly generated.

At this time, the flow rate adjusting means for metering the processing gas sucked from the suction pipe into the suction chamber of the fine particle capturing pipe is provided with a negative pressure generated in the fine particle capturing pipe and the fine particles contained in the processing gas. The flow rate is set in accordance with the properties of, for example, the particle size and the presence or absence of a solid lump. That is, for example, when the negative pressure generated in the particle capturing tube is weak, the suction amount of the processing gas is reduced to ensure that the processing gas comes into contact with the jet stream in the particle capturing tube, and that the gas generated in the particle capturing tube is reduced. If the negative pressure is high, the suction capacity of the processing gas is increased to improve the processing capacity.

[0011] As described above, the processing gas sucked into the suction chamber by the negative pressure formed by the high-pressure fluid linearly injected into the fine particle capturing tube is the peripheral surface of the jet stream having the strongest negative pressure. Since all of the processing gas comes into contact with the jet stream immediately before the high-pressure fluid reaches the extrusion side downstream from the position where the high-pressure fluid is fully spread in the particle capturing tube, the fine particles are captured by the jet stream, The jet stream capturing the fine particles and the processing gas are sent to the discharge-side opening end of the fine particle capturing tube as a unitary unit. Also,
In the case where the discharge-side open end of the particle capturing tube is connected to the gas / liquid separator, the jet stream gas and liquid discharged from the discharge-side open end are separated, and the liquid is again pumped by the pressurizing pump. It can be returned to the fluid being pressurized.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a device for capturing suspended particles according to the present invention. FIG. 1 is a partially cutaway front view showing a schematic configuration of a suspended particulate trapping device attached to an incinerator, and FIG. 2 is a plan view thereof. In the drawing, reference numeral 1 indicates the entire device. The incinerator 2 is divided into a combustion section 4 and a flue section 5 which communicate with each other at an upper portion by a partition wall 3 which rises an inner chamber of the furnace from a bottom 2a. The crater of the combustion burner 7 faces the lower part of the roaster 6.

Then, the combustion part side wall 2 on the upper part of the roastle 6
An incineration material inlet 8 is opened at b, and an ash scraping opening 9 is opened at the combustion part side wall 4a at the lower part of the roaster 6. Further, a chimney 10 and a suction pipe 12 for supplying smoke to a suspended particulate capturing device 11 described later are connected to the upper wall 2c of the flue section 5, and a sediment scraping-out port 13 is provided on the flue section side wall 2d. is there. The suspended particulate capturing device 11 includes a substantially rectangular parallelepiped storage tank 15 that stores water 14 and has an open upper end.
It is provided with a pressure pump 17 for taking out the water 14 from the water suction port 16 and pressurizing the same, and negative pressure forming means 18 for injecting the water pressurized by the pressure pump 17 to form a negative pressure. I have.

The negative pressure forming means 18 includes a pressurizing pump 17
Nozzle 19 for linearly ejecting the high-pressure water supplied from the nozzle is attached to a protection tube 21 provided at one end of the fine particle capturing tube 20, and the inside of the protection tube 21 is jetted from the fluid ejection nozzle 19 by a jet stream. An intake hole 22 for sucking outside air with a negative pressure generated in the air is erected in the protection tube 21, and the outside air sucked from the suction hole 22 is mixed with a jet flow in the protection tube 21 to form a mixed air jet flow. The mixture jet stream injected linearly from the protection tube 21 is
When the inside of the jet pump M. is fully expanded, a large negative pressure is formed in the suction chamber 23 formed in the vicinity of the fluid ejection nozzle 19 of the fine particle capturing tube 20. J. P.

The suction chamber 23 has an end portion 12a of the suction pipe 12 provided on the upper wall 2c of the flue section 5.
The suction pipe 12 has a flow control means 24 for controlling the flow of smoke (gas) containing fine particles at an intermediate portion thereof.
Is provided. The flow rate adjusting means 24 is formed of an on-off valve whose opening area is manually adjusted. The flow rate adjusting means 24 adjusts the back pressure of the high-pressure fluid ejected from the fluid ejection nozzle 19 to spread the high-pressure fluid. It also works to adjust the position. Further, the discharge port 20 a of the fine particle capturing tube 20 is connected to a gas / liquid separation device 25 disposed above the storage tank 15. The gas / liquid separation device 25 includes a swirl chamber 26 formed in a closed cylindrical shape and an exhaust pipe 27 provided at a central portion of a canopy 26a. It is connected tangentially upward. A demister 28 is attached to the upper end opening of the exhaust pipe 27.

The operation of the apparatus for trapping suspended particles 1 configured as described above will now be described. First, when the pressure pump 17 is operated, the water 1 stored in the storage tank 15 from the water suction port 16 is discharged.
4 is pressurized by a pressurizing pump 17 and supplied to a fluid ejection nozzle 19. The high-pressure water supplied to the fluid ejection nozzle 19 is
The fluid is sprayed from the fluid spray nozzle 19 into the protection tube 21 as a jet stream. When the injected jet flow spreads in the protection tube 21, a negative pressure is generated in a portion of the protection tube 21 near the fluid ejection nozzle 19, and the negative pressure sucks the outside air from the intake hole 22 and the jet in the protection tube 21. The stream becomes a mixed jet stream. When the air-jet stream thus formed is injected into the fine particle capturing tube 20 and spreads completely in the fine particle capturing tube 20, a continuous piston working in the fine particle capturing tube 20 toward the end of the discharge port 20a side is formed. (The portion indicated by the dashed line P in the figure) acts to generate a large negative pressure in the suction chamber 23.

The negative pressure generated in the suction chamber 23 is applied to the suction pipe 12.
And acts on the flue chamber 5 of the incinerator 2. On the other hand, the incinerated material is put on the rostral 6 of the incinerator 2 while the negative pressure forming means 18 is operated as described above, and is ignited and burned by the combustion burner 7. Then, particularly in the early stage of combustion, smoke containing tar, moisture, and fine particles of harmful components is generated due to incomplete combustion or the like. Tar and moisture generated in the flue section 5 and smoke containing fine particles of harmful components are applied to the negative pressure forming means 1 acting here.
While the flow rate is adjusted by the flow rate adjusting means 24 by the negative pressure of 8, the liquid is introduced into the suction chamber 23 via the suction pipe 12 and is sucked into the jet stream of the fine particle capturing pipe 20 to be captured as well as fine particles. The mist of odors, which are invisible particles, is trapped in the jet stream, and then tar, moisture, fine particles of harmful components and the like in the smoke are successively captured in the jet stream. When the smoke in the flue section 5 is squeezed by the flow rate adjusting means 24, the smoke is slowly reduced little by little.
Therefore, the velocity difference from the high-speed fluid ejected from the fluid ejection nozzle 19 becomes large, and a negative pressure on the peripheral surface of the fluid to be fed by the Bernoulli's theorem is also strongly generated. Conversely, when the flue section 5 is opened by the flow control means 24, a large amount of smoke can be processed.

Here, the action in the fine particle capturing tube 20 in which the fine particles are captured by the jet stream will be described in more detail.
The mixture jet jet injected from 1 into the fine particle capturing tube 20 flies at a considerably high speed in the form of countless large and small water droplets.
In this way, a pressure drop due to the speed difference is generated around the water droplet flying at a high speed by Bernoulli's principle, and the countless drop of the pressure is collected by the above P portion of the particle capturing tube 20 into a particle capturing tube. It appears as a large negative pressure formed at 20. Therefore, the smoke sucked into the suction chamber 23 by the negative pressure is sucked and contacted by the flying water droplets, so that tar, moisture, and fine particles of harmful components in the smoke are surely adsorbed and captured by the flying water droplets. It is done.

Since a negative pressure is generated in the fine particle trapping tube 20 by such an action, the flow control of the flow control valve 24 provided in the middle of the suction pipe 12 is performed by the flow control valve 2.
When the flow rate is set to a large value by opening the nozzle 4, the back pressure against the mixed jet flow becomes low, so that the flying distance of the mixed jet flow becomes long and the whole apparatus becomes large. The air jet flow is also likely to decrease,
Conversely, when the flow rate of the flow rate adjusting means 24 is reduced, the trapping efficiency of the fine particles is reduced accordingly, and the setting is made in consideration of the above. Thus, the air-jet stream capturing the fine particles of tar, moisture, and harmful components in the smoke flows into the fine particle capturing tube 20.
Flows into the gas / liquid separation device 25 from the discharge port 20a of the circulating chamber 26, and when circling in the swirling chamber 26, gas and liquid are separated by a centrifugal action due to a difference in specific gravity. The gas component flows down to 15 and is discharged outside from the exhaust pipe 27 through the demister 28.

Further, solid lump such as soot contained in the liquid component flowing down to the storage tank 15 along the side wall 26b of the swirling chamber 26 precipitates in the storage tank 15, and as shown in FIG. The vertical partition wall 29 can prevent the pressurizing pump 17 from sucking the solid lump even when the flowing liquid is used for the water pressurized by the pressurizing pump 17. is there. In order to convert the jet stream jetted from the fluid jet nozzle 19 into a mixed jet stream in the protective tube 21, outside air is sucked from the intake hole 22.
As shown in (2), when the smoke is sucked from the flue chamber 5 through the metering valve 30, the trapping efficiency of the suspended particulates can be further improved. Further, in the above embodiment, the suspended particulate capturing device is attached to the incinerator,
It is needless to say that the present invention is not limited to such a material, and can be applied to dust treatment and harmful gas adsorption treatment.

Further, in the above embodiment, one fluid ejection nozzle 19 is provided toward the protection tube 21.
As shown in FIG. 4, it is conceivable to provide a plurality of fluid ejection nozzles 19 and a plurality of protection tubes 21 corresponding thereto.
In this case, the plurality of high-pressure fluids injected into the fine particle capturing tube 20 generate a negative pressure due to a speed difference between the surrounding fluid and a gas to be stopped, and a plurality of high-pressure fluids due to the viscosity of the negative pressure and air. The high-pressure fluid gradually spreads while maintaining the surrounding negative pressure, and the negative pressures formed by a plurality of adjacent high-pressure fluids fuse together, so that the plurality of high-pressure fluids fill the space 20 for capturing fine particles. It will be in a spread state. Then, this jet flow acts like a continuous piston P acting toward the discharge port (discharge-side opening end) 20 a of the particle capturing tube 20, and the vicinity of the fluid injection nozzle 19 of the particle capturing tube 20. A strong negative pressure is formed by fusing together negative pressures formed by a plurality of high-pressure fluids.

When the negative pressures formed around the plurality of high-pressure fluids are united by fusing together, the fused negative pressures act on the high-pressure fluid, and the high-pressure fluid is more rapidly expanded. As a result, the distance from the fluid ejection nozzle to the integration of the negative pressures into one unit is further reduced. Then, the processing gas sucked into the suction chamber by this negative pressure is sucked to the peripheral portion of the jet stream having the strongest negative pressure, so that all of the processing gas immediately comes into contact with the jet stream and a plurality of high-pressure jet streams are formed. Before the fluid reaches the extrusion side downstream from the position where it has fully spread in the particle capturing tube, the particles are captured by the jet stream, and then the multiple jet streams capturing the particles and the processing gas are united together It is extruded to the discharge-side open end 20a of the particle capturing tube 20, and is fed.

Accordingly, while maintaining a sufficient particle capturing ability, the distance from the fluid injection nozzle to the integration of the negative pressures and the negative pressures is shortened to shorten the length of the particle capturing tube 20 and the apparatus is constructed. There is also the advantage that it can be compacted. In addition, in the above embodiment, the fluid ejection nozzle 1
The high-pressure water is injected from the nozzle 9 to form an air-jet mixture with the protective tube 21. As shown in FIG. Needless to say, high-pressure water may be directly injected from the fluid injection nozzle 19 to the particle capturing tube 20. Further, as shown in FIG. 5, in the present invention, it is needless to say that the gas / liquid separation device 25 is not essential and can be omitted. Although illustration is omitted, the flow rate adjusting means 24 may be an automatic opening / closing valve that detects the negative pressure of the suction chamber 23 and changes the opening degree instead of a manual opening / closing valve, or may be formed with a fixed orifice. Of course you can.

[0024]

As described above, the apparatus for trapping suspended particles according to the present invention, when the mixed jet stream formed by the protective tube is jetted into the particle capturing tube and flies in the form of particles,
The particles of the flying fluid form a negative pressure around the particles, and in the front part of the particles of the fluid, they fly through the particle capturing tube while compressing the air, which spreads completely inside the particle capturing tube, and the negative pressure around the particles At the same time, the combined negative pressure and the combined compressed air at the front part of the particles combine to act as a continuous piston. A large amount of negative pressure is generated near the fluid ejection nozzle at a high pressure.

When the negative pressures formed around the particles of the fluid fuse with each other and the compressed air in the front part of the particles is united, the negative pressure and the compressed air are adjacent to each other. Since the high-speed fluid rapidly spreads by acting on the flying particles, the high-speed fluid is ejected from a plurality of fluid ejection nozzles, so that the fluid from the fluid ejection nozzle is fully spread in the fine particle capturing tube. The distance to the position is greatly reduced.

Further, while the negative pressure formed in the fine particle trapping tube is measured by the flow rate adjusting means, the processing gas sucked into the fine particle trapping tube via the suction tube and the suction chamber becomes the jet flow having the strongest negative pressure. All of the processing gas immediately comes into contact with the jet stream, and the fine particles form a jet stream before the mixed jet stream reaches the extrusion side downstream from the position where the mixed gas jet fully spreads in the fine particle capturing tube. The plurality of jet streams that have been trapped and trapped the fine particles and the processing gas are sent to the discharge-side open end of the fine particle trapping tube in a united manner.
Therefore, for example, water that forms a jet stream can also be used effectively, and the apparatus can be made smaller and used as compared with a conventional showering type washing tower in which water droplets push away the processing gas and fly. There is an advantage that the amount of water can be greatly reduced, and the initial cost and running cost can also be significantly reduced.

Further, a flow control means is provided between the open end of the suction pipe and the suction chamber, and by controlling the flow control means, the back pressure against the jet flow flowing through the fine particle capturing pipe is adjusted. And a strong negative pressure can be formed, but the position where the jet stream spreads is set as close to the fluid injection nozzle as possible to shorten the particle trapping tube, thereby reducing the size of the entire device There is also the advantage that it can be done.

In addition, since the processing gas is sucked into the suction chamber while being metered by the flow rate adjusting means by the negative pressure formed near the fluid injection nozzle of the fine particle trapping tube, the shower gas is sucked like a showering type washing tower. The processing gas sucked into the suction chamber is sucked into the jet flow, and the extremely small Since the contact between the mist-like particles and the jet stream is favorably performed, there is an advantage that the dust collection efficiency can be greatly improved.

In the case where the discharge-side open end of the fine particle trapping tube is connected to the gas / liquid separator, the jet stream gas and liquid discharged from the discharge-side open end are separated and discharged. In the case where the fluid is returned to the place where the fluid is pressurized by the pressurizing pump again, the fluid pressurized by the pressurizing pump, for example, water can be circulated and used. This has the advantage that the running cost can be further reduced.

In addition, since the negative pressure forming means is constituted by a mixed type jet pump for forming a negative pressure by injecting the mixed jet stream into the fine particle capturing pipe, it is included in the mixed jet stream. The air and / or the processing gas acts as a cushion between the mixture jet stream and the inside of the particulate trapping tube in which it flows, preventing the jet flow from damping and providing a strong negative pressure to the particulate trapping tube. Can be formed. Thus, since a large amount of processing gas can be supplied to the suction chamber for processing by opening the flow rate adjusting means, there is an advantage that the processing capacity can be further improved.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view showing a schematic configuration of a suspended particulate capturing device attached to an incinerator.

FIG. 2 is a plan view showing a schematic configuration of a suspended particulate capturing device attached to an incinerator.

FIG. 3 is a vertical sectional side view showing a modified example of the negative pressure forming means.

FIG. 4 is a vertical sectional side view showing a modified example of the air-mixing type jet pump portion of the negative pressure forming means.

FIG. 5 is a vertical sectional side view showing another modified example of the negative pressure forming means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Suspended fine particle capturing device 12 ... Suction pipe 17 ... Pressurizing pump 19 ... Fluid injection nozzle 20 ... Fine particle capturing pipe 21 ... Pipe (protection pipe) 23 ... Suction chamber 24: Flow control means 25: Gas / liquid separator J. P ・ ・ ・ Jet pump

Claims (2)

(57) [Claims] A jet pump for jetting a high-pressure fluid supplied from the pressurizing pump to the microparticle capturing tube to form a negative pressure, the jet pump comprising: The pump is provided with a fluid injection nozzle and a protection tube in front of the fluid injection nozzle concentrically with the fluid injection nozzle, and injects a pressurized fluid from the fluid injection nozzle into the protection tube to form a negative pressure in the protection tube. Air is sucked by the negative pressure formed in the tube to convert the fluid in the protective tube into a mixed jet stream, and the mixed jet stream is jetted from the protective tube to the fine particle capturing tube to form a negative pressure in the fine particle capturing tube. A suction chamber is provided between the protective tube and the fine particle capturing tube, and a suction chamber for taking out the negative pressure formed by the air-jet pump is formed between the protective tube and the particle capturing tube. Float the other end of the suction pipe connected to An opening is made toward the gas containing the particles, the gas containing the suspended particles is sucked into the particle capturing tube from the opening end, and the suspended particles in the sucked gas are brought into contact with the mixed jet stream to be trapped. An apparatus for capturing suspended particulates, comprising: 2. The apparatus for trapping suspended particles according to claim 1, wherein the discharge-side open end of the particle trapping tube is connected to a gas-liquid separator.