JP2004188320A - Mixing apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mixing apparatus of gas and liquid capable of forming a satisfactory mixed state and an atomized state when mixing the gas and liquid, and constituting a vapor producing apparatus which is easily manufactured at low cost when being applied for the purpose of vapor production. <P>SOLUTION: The liquid to be mixed is allowed to flow into the gas to be mixed at a prescribed angle (α) to the flowing direction of the gas and is mixed with the gas. After mixing, the gas and liquid are allowed to flow to the outside through a path. Therein, the ratio (L/D) of the length L of the path to the diameter D of cross-section of the path is set to be a predetermined value. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a mixing device for mixing a gas and a liquid, and more particularly to a mixing device capable of generating a good spray state after mixing.
[0002]
[Prior art]
Conventionally, the technology of mixing gas and liquid has been used in combustion burners, etc., where fuel oil and gas such as air introduced from different systems are mixed, and jetted in a state where both are mixed from the tip. I do. The ejected fuel oil becomes fine particles in the jet, that is, atomizes and burns by ignition. If the spray state after the ejection is good, good combustion can be performed.
[0003]
On the other hand, conventionally, various devices for generating steam have been used, and those devices generally generate water vapor by heating water in a container by a fire obtained by burning fuel. . For example, as such apparatuses, there are a general boiler, an apparatus described in the following patent document, and the like.
[0004]
[Patent Document 1]
JP-A-2002-168401 (pages 2-6, FIG. 1)
[0005]
[Problems to be solved by the invention]
However, there are many points where the state and behavior of fluid when gas and liquid are mixed are not fully understood.Therefore, in the case of a conventional mixing device such as a combustion burner, the specifications such as dimensions and shapes are empirically determined. Often decided. Therefore, after mixing, a good mixing state and a spraying state cannot be generated, or it takes time to determine the specifications of the optimum mixing apparatus.
[0006]
In addition, the above-described conventional steam generator usually requires a high-pressure vessel in principle, so that the structure is complicated and the apparatus must satisfy legal standards. Therefore, installation of the steam generator was not easy, and required time and cost.
[0007]
Therefore, an object of the present invention is to provide a good and inexpensive steam generating device that can generate a good mixing state and a spray state when mixing a gas and a liquid, and when applied to the purpose of generating steam. It is to provide a gas-liquid mixing device that can be configured.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, one aspect of the present invention is to mix a liquid to be mixed by flowing a liquid to be mixed at a predetermined angle with respect to a flow direction of the gas, and after mixing. And flowing the gas and liquid out through a path in which the ratio between the length and the diameter of the cross section has a predetermined value. Therefore, according to the present invention, it is possible to reduce the thickness of the liquid film generated at the outlet of the mixing device and to reduce the spray particle diameter after jetting from the mixing device. It is possible to generate a mixed state and a spray state.
[0009]
In order to achieve the above object, another aspect of the present invention is directed to a mixing device for mixing a flowing gas and a liquid, wherein a gas nozzle for guiding the flowing gas, and a liquid nozzle for guiding the flowing liquid. The gas nozzle and the liquid nozzle are open, having a path of a circular cross section for guiding the gas and the liquid flowing from the gas nozzle and the liquid nozzle and ejecting the liquid to the outside of the mixing device, a mixing nozzle, The smaller angle (α) of the angle between the direction in which the gas flows in the gas nozzle and the direction in which the liquid flows in the liquid nozzle is not less than 50 ° and not more than 90 °; A circular cross section of a path of the mixing nozzle having a distance (L) from a position at which the flowing gas and liquid merge into a position at which the gas and liquid are jetted out of the mixing device. Proportion to the diameter (D) (L / D) is that which is characterized in that at least 1.0.
[0010]
Further, in the above-mentioned invention, a preferred embodiment is characterized in that the inflowing liquid is water, and the inflowing gas is heated to a saturation temperature of the water or higher. This makes it possible to easily generate superheated steam.
[0011]
Further objects and features of the present invention will become apparent from the embodiments of the present invention described below.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, such embodiments do not limit the technical scope of the present invention. In the drawings, the same or similar components will be described with the same reference numerals or reference symbols.
[0013]
FIG. 1 is a structural diagram according to an embodiment of a mixing apparatus to which the present invention is applied. FIG. 1A shows a cross section along a flowing direction of a gas and a liquid to be mixed, and FIG. 1B shows an AA view of FIG. 1A. ing. The mixing apparatus 1 according to the present embodiment shown in FIG. 1 combines and mixes gas and liquid flowing from different systems, and ejects the mixed gas and liquid to the outside to generate a spray state. is there.
[0014]
As shown in FIG. 1, the mixing apparatus 1 includes a gas nozzle 2, a liquid nozzle 3, and a mixing nozzle 4. The gas nozzle 2 is a path having a circular cross section that takes in the gas to be mixed and guides the gas to the mixing nozzle 4, and has a gradually decreasing cross-sectional area in order to increase the flow velocity. The liquid nozzle 3 is a path having a circular cross section that takes in the liquid to be mixed and guides the liquid to the mixing nozzle 4, and opens on the wall surface of the mixing nozzle 4 as shown in FIG. Here, the liquid nozzle 3 is provided so that its direction and the direction of the gas nozzle 2 form a predetermined angle α. The angle α is an angle between the flow direction of the gas before mixing and the flow direction of the liquid, and is hereinafter referred to as a mixing angle.
[0015]
The mixing nozzle 4 is a path having a circular cross section for mixing the gas and liquid flowing from the gas nozzle 2 and the liquid nozzle 3 and ejecting the mixed gas and liquid to the outside. Here, the mixing nozzle 4 has an inner diameter D (hereinafter, referred to as a mixing nozzle diameter) of a circular cross section of the mixing nozzle 4 and a distance L (a distance from a position where the gas and the liquid of the mixing nozzle 4 merge to a position where the gas and the liquid are ejected to the outside). 1 (a), which is hereinafter referred to as “mixing distance”). In the present embodiment, the gas nozzle 2 and the mixing nozzle 4 are configured to be in the same direction.
[0016]
In the mixing apparatus 1 having such a configuration, the liquid to be mixed flows in the direction of the arrow A shown in FIG. 1A, and is mixed in the direction of the arrow B shown in FIG. Gas flows into the liquid nozzle 3 and the gas nozzle 2, and the two merge at the mixing nozzle 4. After the merging, the two flow while mixing in the mixing nozzle 4, and are ejected in the direction of arrow C shown in FIG. After the ejection, the liquid flows in an atomized state, that is, in a spray state, and flows in a pipe 5 provided following the mixing device 1. Note that a configuration in which the pipe 5 is not provided may be adopted.
[0017]
The mixing apparatus 1 according to the present embodiment having the above-described structure has the mixing angle α of 50 ° or more and 90 ° or less, and the mixing distance L and the mixing nozzle diameter D described above. It is characterized in that the ratio L / D is designed to be 1.0 or more. These characteristics are based on the results of experiments described below, and by using such specifications, it is possible to generate a good mixed state of gas and liquid and a good spray state after mixing. It becomes.
[0018]
FIG. 2 is a diagram for explaining the above experiment. FIG. 2A is a diagram showing a configuration of the mixing device 10 used in the experiment, and FIG. 2B is a diagram for explaining a phenomenon appearing in the experiment. As shown in FIG. 2A, the experiment is performed in a mixing device 10 having a configuration similar to that of the above-described mixing device 1, and the gas nozzle 20, the liquid nozzle 30, and the mixing nozzle 40 are each made of a transparent material. And the mixing state of gas and liquid was visually observed from the outside.
[0019]
The experiment was performed by mixing the gas flowing from the arrow D in FIG. 2A and the liquid flowing from the arrow E in FIG. 2A. The mixing is performed a plurality of times by changing the value of the ratio L / D of the mixing angle α, the mixing distance L, and the mixing nozzle diameter D which is considered to be given.
[0020]
FIG. 2B shows a phenomenon when gas-liquid is mixed in the experiment. The gas and liquid flowing from the gas nozzle 20 and the liquid nozzle 30, respectively, merge in the mixing nozzle 40, mix with each other, and flow in the mixing nozzle 40. The region where the gas and liquid are mixed and flowing as described above is the mixing region 50 shown in FIG.
[0021]
On the other hand, a part of the liquid flowing into the mixing nozzle 40 from the liquid nozzle 30 does not mix with the gas and adheres to the wall surface of the mixing nozzle 40 to form a liquid film. Such a liquid film is the annular liquid film 60 shown in FIG.
[0022]
As shown in FIG. 2B, the gas-liquid mixed by forming the mixing area 50 is ejected downward from the mixing nozzle 40 to form a spray state. In FIG. 2B, t is the thickness of the annular liquid film 60 at the outlet of the mixing nozzle 40 (hereinafter, referred to as the nozzle outlet liquid film thickness), and d is the particle size of the liquid after ejection ( Hereinafter, referred to as an average spray particle size). Then, when the nozzle outlet liquid film thickness t is small and the average spray particle size d is small, it is determined that the mixture state and the spray state are good. Therefore, in the experiment under each condition, the nozzle outlet liquid film thickness t and the average spray particle diameter d are measured as the experimental results.
[0023]
FIG. 3 is a diagram showing the results of an experiment performed by changing only the mixing angle α. As shown in the graph of FIG. 3, the tendency of the nozzle outlet liquid film thickness t and the average spray particle diameter d when the gas and the liquid are mixed while changing the mixing angle α is the same, and the mixing angle α becomes 50 ° or less. And rapidly worsen (see FIG. 3). That is, when the mixing angle α is 50 ° or less, the nozzle outlet liquid film thickness t sharply increases, and the average spray particle diameter d sharply increases. Therefore, from this experimental result, it is considered that the mixing angle α is an influential factor of the mixing state and the spraying state, and it is necessary to set the mixing angle α to 50 ° or more in order to generate a good mixing state and the spraying state. It is considered that there is.
[0024]
FIG. 4 is a diagram showing the results of an experiment conducted by changing only the ratio L / D of the mixing distance L and the mixing nozzle diameter D. As shown in the graph of FIG. 4, the tendency of the nozzle outlet liquid film thickness t and the average spray particle diameter d when the gas and the liquid are mixed while changing the ratio L / D are the same. When the value becomes 0 or less, the result rapidly deteriorates (see FIG. 4G). That is, when the ratio L / D is 1.0 or less, the nozzle outlet liquid film thickness t sharply increases, and the average spray particle diameter d sharply increases. Therefore, from this experimental result, it is considered that the ratio L / D is an influential factor of the mixed state and the spray state, and in order to generate a good mixed state and the spray state, the ratio L / D is 1.0 or more. It is considered necessary to do so.
[0025]
As described above, the mixing device 1 according to the present embodiment is configured such that the mixing angle α is equal to or greater than 50 ° based on the above-described experimental results, and that the ratio L of the mixing distance L and the mixing nozzle diameter D is L. Since / D is designed to be 1.0 or more, good mixing of gas and liquid is possible. Specifically, the liquid film (t) at the outlet of the mixing nozzle 4 can be made thinner, and the particle diameter (d) of the liquid after jetting can be made smaller, so that a good mixing state and a spraying state can be generated. .
[0026]
Next, a case where the present mixing apparatus 1 is applied as a steam generator will be described. FIG. 5 is a diagram showing the configuration of each device and the flow of fluid when applied as a steam generator. In the application example shown in FIG. 5, the liquid to be mixed by the mixing device 1 is hot water, and the gas to be mixed by the mixing device 1 is superheated gas. Is to be generated.
[0027]
A water tank 11 shown in FIG. 5 is a tank that stores water supplied to the mixing device 1 as the hot water, and a pump 12 is a device that supplies water from the water tank 11 to the mixing device 1. A heater is provided on the outer periphery of the hot water pipe 13 for guiding water from the pump 12 to the mixing device 1 to increase the temperature of supplied water. This facilitates evaporation of water. Note that the hot water pipe 13 may be provided with a means such as supplying hot water instead of a heater.
[0028]
The gas heater 14 shown in FIG. 5 is a device that heats the gas supplied to the mixing device 1 as the superheated gas, and the gas superheater pipe 15 further converts the gas heated by the gas heater 14 into water. This is a pipe that is heated to a temperature equal to or higher than the saturation temperature and is guided to the mixing device 1 while keeping the temperature. Accordingly, the gas superheater pipe 15 is also provided with a heater or the like for superheating and keeping heat. The type of gas used as the gas is not limited, and for example, nitrogen can be used. Further, the above-mentioned water saturation temperature or higher means, for example, 100 ° C. or higher when the pressure is atmospheric pressure.
[0029]
Further, the mixing device 1 to which the hot water and the superheated gas are supplied has the above-described configuration, and the steam pipe 16 guides the mixed fluid into superheated steam, and guides the steam to a steam supply destination. It should be noted that the device configuration before and after the mixing device 1 described above is merely an example, and other configurations are possible.
[0030]
In the steam generator according to the application example described above, water (arrow h in FIG. 5) from the water tank 11 is superheated by the hot water pipe 13 to become hot water (for example, at 80 ° C.) and supplied to the mixing device 1. (Arrow n in FIG. 5). On the other hand, the gas (arrow リ in FIG. 5) is superheated by the gas heater 14 and the gas superheating pipe 15 to be supplied as superheated gas to the mixing device 1 (arrow の in FIG. 5). Then, the hot water and the superheated gas are mixed in the mixing device 1, and a good mixing state and a spray state are generated as described above, so that the hot water evaporates rapidly and becomes superheated steam in the steam pipe 16 (FIG. 5). Arrow ヲ). The generated superheated steam is provided to the supply destination (arrow W in FIG. 5).
[0031]
As described above, by applying the mixing device 1 according to the present invention as a steam generating device, good mixing of gas and liquid is possible, so that good steam can be easily generated. Further, the structure is simpler than that of a conventional steam generator, and the device can be provided at low cost.
[0032]
The protection scope of the present invention is not limited to the above embodiments, but extends to the inventions described in the claims and their equivalents.
[0033]
【The invention's effect】
As described above, according to the present invention, in the gas and liquid mixing device, the thickness of the liquid film at the outlet thereof can be reduced, and the spray particle diameter after jetting from the mixing device can be reduced. It is possible to produce good mixing and spraying conditions. In addition, by applying the mixing device according to the present invention as a steam generating device, good mixing of gas and liquid is possible, so that good steam can be easily generated.
[Brief description of the drawings]
FIG. 1 is a structural diagram according to an embodiment of a mixing apparatus to which the present invention is applied.
FIG. 2 is a diagram for explaining an experiment of gas-liquid mixing.
FIG. 3 is a diagram showing the results of an experiment performed by changing only the mixing angle α.
FIG. 4 is a diagram showing the results of an experiment performed by changing only the ratio L / D of the mixing distance L and the mixing nozzle diameter D.
FIG. 5 is a diagram showing a configuration of each device and a flow of fluid when applied as a steam generator.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Mixing device 2 Gas nozzle 3 Liquid nozzle 4 Mixing nozzle 5 Pipe 10 Mixing device 11 Water tank 12 Pump 13 Hot water pipe 14 Gas heater 15 Gas superheating pipe 16 Steam pipe 20 Gas nozzle 30 Liquid nozzle 40 Mixing nozzle 50 Mixing area 60 Annular Liquid film α Mixing angle D Mixing nozzle diameter L Mixing distance d Average spray particle size t Nozzle outlet liquid film thickness

Claims (2)

A mixing device for mixing the incoming gas and liquid,
A gas nozzle for introducing the flowing gas,
A liquid nozzle for introducing the flowing liquid,
The gas nozzle and the liquid nozzle are open, having a path of a circular cross section for guiding the gas and the liquid flowing from the gas nozzle and the liquid nozzle and ejecting the mixture to the outside of the mixing device, including a mixing nozzle,
A smaller angle (α) among angles formed by a flowing direction of the gas in the gas nozzle and a flowing direction of the liquid in the liquid nozzle is 50 ° or more and 90 ° or less,
The diameter (L) of the circular cross-section of the path of the mixing nozzle, which is a distance (L) from a position where the flowing gas and liquid merge in the mixing nozzle to a position where the gas and liquid are jetted out of the mixing device. A mixing device, wherein the ratio (L / D) to D) is 1.0 or more. In claim 1,
The incoming liquid is water;
The mixing device, wherein the flowing gas is heated to a temperature higher than a saturation temperature of the water.

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