JP5037142B2 - Multiphase mist spraying system - Google Patents

Description

  The present invention relates to a multi-phase mist spraying system for spraying mist containing bubbles.

In recent years, water in which ozone bubbles are mixed has been sprayed for sterilization and deodorization inside kitchens and food factories. And the spray of water mixed with ozone bubbles is performed using an ejector, and ozone gas is sucked and mixed as bubbles at the negative pressure generated in the middle of the water flow from the nozzle to the diffuser. Sprayed as mist mixed with ozone bubbles.
On the other hand, spraying of high-pressure water mixed with ozone has also been proposed, in which high-pressure water and ozone-containing air are sent to the nozzle, and a plurality of spray streams of high-pressure water are sprayed independently from the nozzle, and a plurality of strips outside the nozzle are sprayed. The spray flow is merged. Also, the ozone-containing air is sucked by the negative pressure generated at the confluence of the high-pressure water spray flow and mixed with the spray flow combined with the high-pressure water, and then sprayed onto the object for cleaning or sterilization (for example, patents) Reference 1).

Japanese Patent Laid-Open No. 2004-283964

  However, there is a problem that simply spraying water in which ozone bubbles are mixed may cause the reaction rate to change due to the humidity of the spraying space and the ozone concentration may be excessive.

  An object of the present invention is to provide a multiphase mist spraying system that controls the concentration of gas in a spraying space to an appropriate value without wetting an object in the spraying space.

  A multi-phase mist spraying system according to the present invention includes a microbubble generating device that generates gaseous microbubbles in a liquid, a first pressurized water supply device that pressurizes the liquid in which the microbubbles are mixed, and a first device that pressurizes the liquid. 2 pressure water supply device, calculation of liquid spray amount based on relative temperature, calculation of second water supply amount based on gas concentration, and first water supply amount obtained by subtracting second water supply amount from liquid spray amount And the control of the first pressurized water supply device according to the first water supply amount and the control of the second pressurized water supply device according to the second water supply amount to control the supply of pressurized water to the spray nozzle. And a spraying device for spraying the supplied pressurized water as a fine particle mist by a one-fluid system.

The effect of the multi-phase mist spraying system according to the present invention is that spraying is performed independently of the concentration of gas and the vapor pressure of the liquid in the space for spraying fine particle mist mixed with gas microbubbles and fine particle mist containing only liquid. The gas concentration and the vapor pressure of the liquid can be controlled independently, and the risk of excessive gas concentration is eliminated.
Further, when a liquid pressurized to high pressure is sprayed, the particle diameter of the mist becomes fine and it takes a short time to evaporate, so that the walls and objects in the room are not wetted.

  The mixed-phase mist spraying system according to the present invention is a mixed-phase mist comprising a liquid phase and a gas-phase mixed phase in which bubbles (hereinafter referred to as bubbles and bubbles having a diameter of 50 μm or less) are mixed in droplets. And a liquid phase mist of only the liquid phase. In particular, the sprayed mixed phase mist and liquid phase mist are fine particle mists having a Sauter particle size of 30 μm or less, and the transpiration rate is fast, so that the surroundings are not wetted by the spraying of the mixed phase mist and liquid phase mist. . The liquid phase and the gas phase according to the present invention can be appropriately selected depending on the application, but in the following description, the liquid phase is composed of water and the gas phase is composed of ozone gas or oxygen gas. .

Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a multiphase mist spraying system according to Embodiment 1 of the present invention. FIG. 2 is a block diagram showing the configuration of the pressurized water supply apparatus according to Embodiment 1 of the present invention. FIG. 3 is a functional block diagram of the control apparatus according to Embodiment 1 of the present invention. FIG. 4 is a sectional view taken along the central axis of the spray nozzle according to the first embodiment of the present invention. FIG. 5 is a diagram showing the measurement result of the particle size distribution of the sprayed mixed phase mist. FIG. 6 is a timing chart of mist spraying.

The mixed phase mist spraying system according to Embodiment 1 of the present invention includes ozone water in which the gas phase is composed of ozone gas and the liquid phase is water, and the mixed phase mist in which ozone gas is mixed as microbubbles and the liquid phase mist of only water are sprayed. Mist spray system. And this ozone water mist spraying system is utilized as a system which sterilizes and deodorizes.
As shown in FIG. 1, an ozone water mist spraying system 1 according to Embodiment 1 is disposed on a ceiling 3 of a room 2 that forms a space that contains an ozone gas in a predetermined amount and is controlled in an atmosphere having a predetermined humidity. Sprayed nozzle 4, pressurized water distribution pipe 5 that distributes pressurized water supplied to the spray nozzle 4, pressurized water supply apparatus 6 that supplies pressurized water via the pressurized water distribution pipe 5, and pressurized water supply apparatus that measures the ozone gas concentration in the space 6 is provided with an ozone gas sensor 8 for transmitting to the temperature sensor 6 and a temperature / humidity sensor 9 for measuring the humidity of the space and transmitting it to the pressurized water supply device 6.
The pressurized water supply device 6 includes an ozone gas generator 11 that generates ozone gas, a water tank 12 that stores water mixed with microbubbles of ozone gas, a microbubble generator 13 that generates microbubbles of ozone gas in the water in the water tank 12, and a microbubble. The first pressurized water supply device 14 that pressurizes and feeds water mixed with water, the second pressurized water feed device 15 that pressurizes and feeds water, and the control device 16 that controls the pressurized water supply device 6 are provided.

The ozone gas generator 11 is a general device that generates ozone gas by using electric discharge.
The microbubble generator 13 is a general high-speed swirling flow type microbubble generator, but is controlled to generate microbubbles having a diameter of 50 μm or less.

  The first pressurized water feeder 14 and the second pressurized water feeder 15 have the same configuration, and the first pressurized water feeder 14 will be described. As shown in FIG. 2, the first pressurized water supply device 14 opens and closes a flow path for draining water in the high pressure pump 40, a main valve 41 disposed on the downstream side of the high pressure pump 40, and the main water distribution pipe 42. A drain valve 43 and a selection valve 44 for selecting supply of pressurized water to the pressurized water distribution pipe 5 are configured.

The main valve 41 and the selection valve 44 are communicated with each other through the main water distribution pipe 42, and the drain valve 43 is communicated with the main water distribution pipe 42 through a drain pipe 46 branched from the middle of the main water distribution pipe 42. The main water pipe 42, the drain pipe 46, and the pressurized water pipe 5 are each made of stainless steel. The high pressure pump 40 and the main valve 41 are communicated with each other by a rubber blade hose 47 to smooth the pulsation generated by the positive displacement high pressure pump 40.
Further, in order to remove dust contained in the pressurized water, a 20 μm square opening filter (not shown) is interposed at the outlet of the high-pressure pump 40.
In addition, after pressurizing with the high-pressure pump 40, it may store in a high-pressure storage container etc., and you may send water to the pressurized water distribution pipe 5. FIG.

  As shown in FIG. 3, the control device 16 is measured by a liquid spray amount calculation means 50 that calculates the spray amount of water based on the dry bulb temperature and the wet bulb temperature measured by the temperature and humidity sensor 9 and the ozone gas sensor 8. Gas spray amount calculation means 51 for calculating the spray amount of ozone gas based on the ozone gas concentration, first water supply amount calculation means 52 for calculating the first water supply amount to be supplied from the first pressurized water supply device 14 from the spray amount of ozone gas, water The second water supply amount calculating means 53 for calculating the second water supply amount obtained by subtracting the first water supply amount from the spray amount of the first water supply, the first pressurized water supply device 14 and the second additional water supply according to the first water supply amount and the second water supply amount. The spray sequence control means 54 for controlling the pressure water supply device 15 and the air diagram database 55 in which the wet air diagram is stored are provided. The control device 16 is composed of a CPU, a RAM, a ROM, and a computer having an interface circuit.

The liquid spray amount calculating means 50 calculates the relative humidity RH (%) based on the wet air diagram from the dry bulb temperature DT (° C.) and the wet bulb temperature WT (° C.) input from the temperature / humidity sensor 9.
Next, the liquid spray amount calculation means 50 sets the water spray amount to zero when the relative humidity RH is greater than or equal to a predetermined value, and conversely when the relative humidity RH is less than the predetermined value, the relative humidity RH (%). Based on the above, the amount of water spray is calculated.

The gas spray amount calculation means 51 calculates the spray amount of ozone gas based on the ozone gas concentration input from the ozone gas sensor 8.
The first water supply amount calculation means 52 calculates the first water supply amount according to the spray amount of ozone gas.
The second water supply amount calculating means 53 calculates the second water supply amount by subtracting the first water supply amount from the water spray amount.
For example, if the spray amount of ozone gas is A gram, and the mixing rate of ozone gas into microbubble water is γ, A / γ gram of water per unit time is sent from the first pressurized water supply device 14, and the spray amount of water is Assuming B grams, (B−A / γ) grams of water is fed from the second pressurized water feeder 15.
Further, assuming that the spray amount of ozone gas is zero gram, B gram of water is supplied from the second pressurized water supply device 15.

  As shown in FIG. 4, the spray nozzle 4 has a substantially cylindrical housing 20. Then, along the central axis of the cylindrical housing 20, a two-stage cylindrical pressurized water receiving cavity 21 in which the upstream diameter that receives the pressurized water supplied from the pressurized water distribution pipe 5 is larger than the downstream diameter, pressure-sensitive reverse The stop valve 22 is housed, and the valve housing cavity 24 and the piece 25 which are larger in diameter than the downstream side of the pressurized water receiving cavity 21 and whose outer edge is partitioned by the rib 23 protruding in the central axis direction are housed. , A jet generating cavity 28 composed of a columnar cavity 26 having the same diameter as the upstream side of the pressurized water receiving cavity 21 and a funnel-shaped cavity 27 connected to the cavity 26, and connected to the tip of the funnel-shaped cavity 27. An orifice 29 is provided continuously.

A pressure-sensitive check valve 22 that opens and closes an opening 21 a on the downstream side of the pressurized water receiving cavity 21 is inserted into the valve housing cavity 24.
When the pressure-sensitive check valve 22 abuts the opening 21 a on the downstream side of the pressurized water receiving cavity 21, a blocking ball 30 that blocks the flow of pressurized water, and one end abuts the blocking ball 30, and a predetermined spring pressure is applied to the blocking ball 30. The other end of the spring 31 is fixed to the rib 23. The spring constant of the spring 31 is set so that the predetermined spring pressure separates the blocking ball 30 and the opening 21a of the pressurized water receiving cavity 21 when the water pressure in the pressurized water receiving cavity 21 reaches 1 MPa. If the predetermined spring pressure is set low, it takes a long time to reach a high pressure when separated and water droplets having a large diameter are sprayed. Further, if the predetermined spring pressure is close to the spray water pressure, the blocking ball 30 cannot be sufficiently separated from the opening 21a, so that the amount of water is restricted. For this reason, the predetermined spring pressure is preferably 0.4 to 1.5 MPa.

  Further, in the jet generation cavity 28, the pressurized water is ejected as a swirling jet, and a piece 25 for colliding with the inner surface of the funnel-shaped cavity 27 is in contact with the inner surface of the cylindrical cavity 26, and the direction of the central axis of the spray nozzle 4 Move while sliding. A spiral groove 32 is dug in the side surface of the piece 25, and a swirl flow path for swirling and ejecting pressurized water is formed by the groove 32 and the inner surface of the cylindrical cavity 26.

  A pressure transducer (model PVD-100ka, measurement range 0 to 10 MPa) 17 attached from the pressurized water distribution pipe 5 is attached to measure the water pressure applied to the pressurized water receiving cavity 21 of the spray nozzle 4. , That is the spray water pressure. Normally, the relationship between the spray water pressure and the output water pressure of the high-pressure pump 40 is obtained in advance, and the spray water pressure is managed by managing the output water pressure of the high-pressure pump 40. A Bourdon tube pressure gauge or the like may be used for measuring the water pressure.

Next, a procedure for spraying pressurized water in the spray nozzle 4 will be described.
When pressurized water is poured into the pressurized water receiving cavity 21 and the water pressure reaches a predetermined value, the blocking ball 30 is pushed and the pressurized water flows into the valve housing cavity 24.
Then, pressurized water pushes one end face of the piece 25 from the hole 23 a formed at the center of the rib 23, and the piece 25 is moved along the central axis of the spray nozzle 4 toward the funnel-shaped cavity 27. The pressurized water passes through the groove 32 while being swirled, and is jetted from the end of the groove 32.
This jet collides with the inner surface of the funnel-shaped cavity 27 to become a collision jet and is sprayed from the orifice 29 as a mist.

Next, the sprayed mist will be described. The mist in this invention means the water droplet of a small diameter. The average particle diameter of the mist is the average body area particle diameter (referred to as the Sauter average diameter) measured by the laser diffraction method at a location 50 mm away from the tip of the orifice 29 on the central axis of the spray nozzle 4. In the laser diffraction method, a laser diffraction particle size measuring device (manufactured by Malvern Instruments, Master Size-S type, used laser: He-Ne laser) was measured in the same manner five times, and the average value was the average particle size of mist. It is used as.
When the spraying water pressure was 5 MPa from the spray nozzle 4 used in the first embodiment, the Sauter average particle size was 20 μm as shown in FIG. In addition, if the spray water pressure is low, the average particle diameter of the mist increases, and if the spray water pressure is high, the average particle diameter of the mist decreases and the spray flow rate increases, but if it is too high, a large shock wave is added to the piping, It is not preferable for safety. For these reasons, the spray water pressure is preferably between 2 MPa and 10 MPa. Furthermore, the spray water pressure is preferably between 5 MPa and 10 MPa so that the Sauter average particle size is 20 μm or less.

  The average particle size of the mist is measured using a laser diffraction particle size measuring device, but may be measured using a Doppler phase particle size measuring device or the like. At this time, since the average particle size varies depending on the type of measuring instrument, it is necessary to measure and compare mist sprayed under the same conditions. For example, the 90% volume particle size of the mist sprayed when the spray water pressure is 5 MPa from the spray nozzle 4 was 60 μm, and the 10% volume particle size was 3 μm.

Next, a sequence for supplying pressurized water from the first pressurized water supply apparatus 14 will be described with reference to FIG. In addition, the sequence which supplies pressurized water from the 2nd pressurized water supply apparatus 15 is the same as that of FIG. 6, and abbreviate | omits description.
The spray sequence control means 54 first opens the main valve 41. At the same time, the drain valve 43 is opened.
Next, the spray sequence control means 54 turns on the high-pressure pump 40 and supplies pressurized water from the blade hose 47 to the main water distribution pipe 42. As a result, the air remaining in the main water distribution pipe 42 is pushed out together with the water from the drain valve 43, and a uniform water pressure is applied in the main water distribution pipe 42.
Next, the spray sequence control means 54 closes the drain valve 43. Thereby, the water pressure in the main water distribution pipe 42 reaches a desired water pressure, for example, 6 MPa.
Next, the spray sequence control means 54 opens the selection valve 44 connected to the spray nozzle 4, and pressurized water is supplied to the spray nozzle 4 via the pressurized water distribution pipe 5. At this time, the water pressure applied by being injected into the pressurized water receiving cavity 21 reaches approximately 0 MPa to 6 MPa in 4 seconds. When the water pressure becomes 1 MPa or more in this way, the pressure-sensitive check valve 22 of the spray nozzle 4 is opened and mist spraying is started.

Conversely, when mist spraying is terminated, the spray sequence control means 54 opens the drain valve 43 to reduce the water pressure in the main water distribution pipe 42. Then, since the water pressure in the pressurized water receiving cavity 21 is reduced to 1 MPa or less, the pressure sensitive check valve 22 is closed and the mist spraying is finished.
Then, after about 3 seconds from the opening of the drain valve 43, the high-pressure pump 40 is turned off and the selection valve 44 is closed. Thereafter, the main valve 41 and the drain valve 43 are closed.

Thus, after the water pressure in the main distribution pipe 42 is once stabilized to a desired value, the pressure of the pressurized water supplied to the spray nozzle 4 is changed from 0 MPa to 6 MPa in a few seconds by supplying water to the pressurized water distribution pipe 5. Can change. And since the pressure sensitive check valve 22 is suddenly opened and the spraying time can be shortened when the water pressure is low, most of the mist having a large particle size seen when spraying when the water pressure is low. It is not sprayed.
Further, when the drain valve 43 is opened, the water pressure in the main water distribution pipe 42 is suddenly lowered, the pressure sensitive check valve 22 is suddenly closed, and the spraying time in a low water pressure state can be shortened. The mist having a large particle size seen when sprayed at a low water pressure is hardly sprayed.

  Next, ozone gas microbubbles mixed in the sprayed mist will be described. Since the microbubbles of ozone gas mixed into the water in the water tank 12 have a diameter of 50 μm or less, the microbubbles of ozone gas mixed into the water in the pressurized water distribution pipe 5 have water pressurized to 6 MPa. The diameter is 13 μm or less. On the other hand, since the sprayed mist has an average particle diameter of 20 μm, ozone gas microbubbles are included in the mist and diffuse together with the mist. Then, ozone gas is released as the mist evaporates.

  If the water pressure is 2 MPa, the diameter of the microbubbles is reduced to 18 μm or less, and the average particle diameter of the sprayed mist is about 30 μm as shown in FIG. In addition, microbubbles of ozone gas are contained in the mist and diffuse together with the mist.

Such an ozone water mist spraying system 1 sprays the amount of ozone gas sprayed from the first pressurized water supply device 14 as a mixed phase mist, and the amount of sprayed water for maintaining the humidity at a predetermined value is sufficient. If not, the remaining water spray amount is fed from the second pressurized water feeding device 15, so that the humidity can be maintained at a predetermined value and the ozone gas concentration can be prevented from becoming excessive.
In addition, after ozone gas is microbubbles with a diameter of 50 μm or less and mixed in water, water is pressurized to a high pressure of 2 MPa or more and sprayed with mist while reducing the diameter of the microbubbles. It is possible to spray mist with bubbles mixed.
Moreover, since water is pressurized and sprayed at a high pressure of 2 MPa or more, the average particle diameter of the mist is 30 μm or less, the transpiration rate is fast, and the walls and objects in the room are not wetted.
In addition, since the microbubbles of ozone gas having a diameter of 50 μm or less are mixed in the water in the water tank 12, the microbubbles float for a long time even in water at atmospheric pressure, and the concentration of ozone gas contained in the sprayed water is reduced. Can be increased. For this reason, ozone gas can be diffused in space with a small amount of water.

Embodiment 2. FIG.
FIG. 7 is a configuration diagram of a multiphase mist spraying system according to Embodiment 2 of the present invention. FIG. 8 is a functional block diagram of a control device according to Embodiment 2 of the present invention.
The mixed-phase mist spraying system according to Embodiment 2 of the present invention sprays a mixed-phase mist in which the gas phase is composed of oxygen gas and the liquid phase is water, and oxygen gas is mixed as microbubbles, and a liquid-phase mist containing only water. It is an oxygen water mist spraying system. The oxygen water mist spraying system is utilized as a system that provides a room with a high-concentration oxygen atmosphere for fatigue recovery or relaxation.
As shown in FIG. 7, the oxygen water mist spray system 7 according to the second embodiment includes an oxygen gas generator 35 and an ozone gas sensor 8 instead of the ozone water mist spray system 1 and the ozone gas generator 11 according to the first embodiment. Instead of the oxygen gas sensor 36 and the control device 16, the control device 16B is different and the other parts are the same.

The oxygen gas generator 35 is a general device that separates and supplies oxygen gas from the air using an adsorbent that preferentially adsorbs nitrogen gas. Note that oxygen gas may be generated by any method as long as oxygen gas can be supplied.
The oxygen gas sensor 36 is a general sensor that measures the oxygen gas concentration in the atmosphere and transmits it to the control device 16B.
As shown in FIG. 8, the control device 16B according to the second embodiment is different from the control device 16 according to the first embodiment in that the gas spray amount calculating means 51B and the first water supply amount calculating means 52B are the same except for the above. Therefore, the same reference numerals are attached to the same parts, and the description is omitted.
The gas spray amount calculating means 51B calculates the spray amount of oxygen gas based on the oxygen concentration measured by the oxygen gas sensor 36.
The first water supply amount calculation unit 52B calculates the first water supply amount according to the spray amount of the oxygen gas.

Such an oxygen water mist spraying system 7 sprays the spray amount of oxygen gas from the first pressurized water supply device 14 as a mixed phase mist, and the spray amount of water for maintaining the humidity at a predetermined value is only the mixed phase mist. If not enough, the remaining spray amount of water is fed from the second pressurized water feeding device 15, so that the humidity can be maintained at a predetermined value and the oxygen gas concentration can be prevented from becoming excessive.
In addition, oxygen gas is microbubbles having a diameter of 50 μm or less and mixed in water, and then water is pressurized to a high pressure of 2 MPa or more and sprayed with mist while reducing the diameter of the microbubbles. It is possible to spray the mist with the microbubbles mixed.
Moreover, since water is pressurized and sprayed at a high pressure of 2 MPa or more, the average particle diameter of the mist is 30 μm or less, the transpiration rate is fast, and the walls and objects in the room are not wetted.
In addition, since the microbubbles of oxygen gas having a diameter of 50 μm or less are mixed in the water in the water tank 12, the microbubbles float for a long time even in water at atmospheric pressure, and the oxygen gas contained in the sprayed water The concentration can be increased. For this reason, oxygen gas can be diffused in space with a small amount of water.

  Here, spraying the mist containing the bubble is described, but the bubble is not necessarily contained in the mist. For example, when the bubble diameter is 30 μm and the mist diameter is 30 μm, the bubbles are not encapsulated in the mist but are released together with the mist spray, so that oxygen can be efficiently supplied into the space.

It is a block diagram of the mixed phase mist spraying system concerning Embodiment 1 of this invention. It is a block diagram which shows the structure of the pressurized water supply apparatus concerning Embodiment 1 of this invention. It is a functional block diagram of the control apparatus concerning Embodiment 1 of this invention. It is sectional drawing along the central axis of the spray nozzle concerning Embodiment 1 of this invention. It is a figure which shows the measurement result of the particle size distribution of the sprayed mixed phase mist. It is a timing chart of mist spraying. It is a block diagram of the mixed phase mist spraying system concerning Embodiment 2 of this invention. It is a functional block diagram of the control apparatus concerning Embodiment 2 of this invention.

Explanation of symbols

  1 Ozone water mist spray system, 2 rooms, 3 ceiling, 4 spray nozzles, 5 pressurized water distribution pipe, 6 pressurized water supply device, 7 oxygen water mist spray system, 8 ozone gas sensor, 9 temperature / humidity sensor, 11 ozone gas generator, 12 water tank , 13 Microbubble generator, 14 First pressurized water feeder, 15 Second pressurized water feeder, 16, 16B Control device, 17 Pressure transducer, 20 Housing, 21 Cavity, 21a Opening, 22 Pressure sensitive check valve, 23 rib, 23a hole, 24 valve housing cavity, 25 pieces, 26, 27 cavity, 28 jet generating cavity, 29 orifice, 30 blocking ball, 31 spring, 32 groove, 35 oxygen gas generator, 36 oxygen gas sensor, 40 high pressure pump , 41 Main valve, 42 Main water pipe, 43 Drain valve, 44 Select valve, 46 Drain pipe, 47 Scan, 50 liquid spray amount calculating means, 51, 51b gas spraying amount calculating means, 52, 52b first water supply amount calculating means, 53 second water supply amount calculation means, 54 a spray sequence control means, 55 psychrometric chart database.

Claims (3)

A microbubble generator for generating gaseous microbubbles in the liquid;
A first pressurized water supply device that pressurizes the liquid in which the microbubbles are mixed;
A second pressurized water supply device for pressurizing the liquid;
The calculation of the liquid spray amount based on the relative temperature, the calculation of the second water supply amount based on the gas concentration , and the calculation of the first water supply amount obtained by subtracting the second water supply amount from the liquid spray amount, A control device for controlling the supply of pressurized water to the spray nozzle by the control of the first pressurized water supply device according to one water supply amount and the control of the second pressurized water supply device according to the second water supply amount ;
A spraying device for spraying the pressurized water sent as fine particle mist in a one-fluid system;
A multi-phase mist spraying system comprising: 2. The mixed phase mist spraying system according to claim 1, wherein the pressurized water to the spray nozzle has a spray water pressure of 2 MPa to 10 MPa . 3. The mixed phase mist spraying system according to claim 1 , wherein the fine particle mist has an average particle size of 30 μm or less which does not wet a wall or an object in a space to be sprayed.

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