JP3282196B2 - Chemical reactor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chemical reaction apparatus for allowing a chemical reaction solution and a gas component (chemical reaction gas component) chemically reacting with the reaction solution to come into gas-liquid contact to cause a chemical reaction to proceed. The present invention relates to a chemical reaction device provided with a chemical reaction gas supply device capable of mixing and supplying fine chemical reaction gas bubbles such as oxidizing gas and reducing gas to a chemical reaction liquid.

[0002]

2. Description of the Related Art
Chemical reaction gas such as oxidizing gas and reducing gas in the chemical reaction device is supplied from a large number of pores of a tubular or plate-shaped chemical reaction gas supply device buried in the liquid in the gas-liquid contact tank. Chemical reaction gas bubbles are subdivided and supplied by pressurizing and ejecting gas into the reaction solution, and chemical reaction gas bubbles are ejected and supplied from the lower part of the cylindrical container containing the chemical reaction solution, and the buoyancy causes chemical reaction. There is a method in which a gas-liquid contact reaction is performed while the reaction solution is being raised, or a method in which a chemical reaction gas is introduced into a reaction tower and the chemical reaction solution is supplied in a mist form to perform a gas-liquid contact reaction.

In a chemical reaction using a chemical reaction gas supplier having these functions, necessary adjustments are basically made according to the supply amount of the chemical reaction gas, the number of each chemical reaction gas supply, and the like. ing. However, in order to develop a high-performance chemical reaction device for energy-saving advanced chemical reactions, in particular, a large amount of fine chemical reaction gas bubbles are generated, and the amount of generated and supplied bubbles is controlled. There is a need.

[0004] That is, the above-mentioned method has the following various disadvantages. For example, in the ejection method, no matter how fine pores are provided, large bubbles having a diameter of about several mm are generated due to the surface tension of the bubbles when the bubbles are ejected from the pores. This has the disadvantage that it is impossible to generate smaller bubbles. Further, as disadvantages of such a system, there are a problem of clogging and a problem of an increase in power cost caused by long-time operation.

[0006] In a conventional chemical reaction gas supply device in a conventional chemical reaction apparatus having the above-mentioned drawbacks and problems,
Since the generation amount of the fine bubbles is small, the residence time of the bubbles in the chemical reaction solution is shortened, and an increase in the amount of the chemical reaction gas taken into the chemical reaction solution cannot be expected. Furthermore, since the diameter, generation amount, and supply amount of fine bubbles cannot be easily controlled, there has been a problem that the gas-liquid contact reaction cannot be efficiently performed.

That is, the above-described chemical reaction gas supply has the following problems. . A large amount of fine bubbles having a diameter of 1 mm or less and up to several tens of μm cannot be generated in a large amount, and the chemical reaction accompanying the gas-liquid renewal cannot be drastically accelerated. . The diameter, distribution, generation amount, and supply amount of the above-mentioned bubbles cannot be easily mechanically controlled as required. . Without the stirrer, it is not possible to create the necessary circulating flow and the stirring action in the chemical reactor. . Clogging occurs due to continuous chemical reaction gas supply, and gas-liquid contact efficiency is reduced, thereby increasing pressure loss. For this reason, long-term continuous operation and significant reduction in operating costs cannot be achieved. . The size of the apparatus including the chemical reaction gas supply device and the compressor for supplying the gas bubbles of the chemical reaction gas becomes large, and there is a restriction in installation, so that downsizing cannot be achieved. . It is difficult to perform optimal control of the chemical reaction by controlling the diameter, distribution, generation amount, etc. of the gas bubbles of the chemical reaction gas by stirring in the chemical reaction tank or adjusting the intake amount of the chemical reaction gas.

[0008]

The present inventors have intensively studied to solve the above-mentioned problems of the prior art, and as a result, have been able to easily supply fine chemical reaction gas bubbles to a chemical reaction solution. A chemical reaction device equipped with a chemical reaction gas supply was developed. That is, the present invention is a chemical reaction device as described below. In the first invention, a porous chemical reaction liquid transfer pipe is exposed in a chemical reaction gas atmosphere and a head difference is set.
And a suction-type chemical reaction gas supply device, which is arranged in the chemical reaction gas supply pipe. and a chemical reaction apparatus characterized by comprising a suction type reaction gas supplying device formed by placement provided water head difference, the third invention is formed by arranged with a water head difference chemistry A chemical reaction device comprising a suction-type chemical reaction gas supply device provided with a porous chemical reaction gas supply tube inside a liquid transfer tube. A fourth invention is the chemical reaction device according to any one of the first to third inventions, wherein the communication hole of the porous tube is an irregular communication hole. The chemical reaction device according to any one of the first to fourth inventions, wherein the chemical reaction liquid transfer pipe and / or the porous chemical reaction gas supply pipe is a porous ceramic pipe.

In a sixth aspect of the present invention, the porous chemical reaction liquid transfer pipe and / or the porous chemical reaction gas supply pipe is a porous metal pipe. A seventh aspect of the present invention is the chemical reaction device according to the first aspect, wherein the communication hole of the porous chemical reaction liquid transfer pipe and / or the porous chemical reaction gas supply pipe has a hole diameter of 500 μm or less. An eighth aspect of the present invention is the chemical reaction apparatus according to any one of the sixth to sixth aspects, wherein a tubular or enclosure-shaped chemical reaction gas supply chamber is provided around the porous chemical reaction solution supply pipe. The chemical reaction device according to any one of the first, second, and fourth to seventh inventions, characterized in that: Then, in the above invention, a porous chemical reaction gas supply pipe or /
And the porous chemical reaction liquid transfer pipe may be of a vertical type, a horizontal type, or an oblique type, and a porous chemical reaction liquid transfer pipe or / and a porous chemical reaction gas supply pipe may be provided. It is good also as a siphon arrangement.

[0010] Further, the porous chemical reaction gas supply pipe and / or the porous chemical reaction liquid transfer pipe may be a horizontal or oblique type retraction pipe. It is preferable to dispose a porous tube at the maximum negative pressure or minimum positive pressure generation site of the type or obliquely placed retraction tube. and again,
It is also preferable that the vertical porous chemical reaction liquid transfer pipe is a gradually expanding pipe. In this case, a porous pipe is provided at the maximum negative pressure generation site above the vertical chemical expansion liquid transfer pipe. What is provided is preferred.

[Action]

In the above invention, first, in the suction / supply of an external chemical reaction gas using an irregular porous tube made of ceramics, the suction system utilizing the head difference is considerably more than the ejection system. A small pressure loss results.
This is the surface area of the outer peripheral wall surface of the tube, the presence of pipe wall thickness, always than the surface area of the inner peripheral wall surface is due to be larger, thus, the water head difference of the present invention using a porous tube
According to the suction system utilizing the method, the generation efficiency of the reactant gas bubbles in the chemical reaction solution is remarkably improved. Second
In addition, in the conventional jetting method, even if the diameter of the pores of an irregular porous tube made of ceramics or the like is reduced to about μm, the diameter of bubbles generated therefrom is increased to about several mm on average. However, according to the suction-type chemical reaction gas supplier utilizing the head difference according to the present invention, the average diameter of the generated bubbles is several tens.
The size can be reduced to 0 μm to several tens μm. Therefore, the contact area between the chemical reaction liquid and the gas bubbles of the chemical reaction gas can be increased to about 10 to 100 times that of the conventional method, and the residence time of the bubbles can be increased to 10 to 100 times. The amount of chemical reaction gas taken into can be dramatically increased.

Third, by controlling the pressure of the chemical reaction gas fed into the chemical reaction liquid transfer tube of the porous tube, the amount of air bubbles sucked can be adjusted without changing the flow rate of the chemical reaction liquid. . This bubble generation amount (suction amount)
, It is possible to achieve high efficiency of the chemical reaction. Fourth, the pressure energy required for sucking the chemical reaction gas from the porous tube only needs to exceed the pressure loss head of the porous tube, and extremely small pressure energy is sufficient. Usually, a head difference of about 50 cm is sufficient. Fifth, as the external chemical reaction gas is uniformly sucked near the inner wall of the porous tube, a flow is formed perpendicular to the wall toward the center of the tube. This flow acts in the direction in which the substance to be attached to the inner wall is peeled off, and as a result, the formation of clogging of the porous tube is less likely to occur. Even if clogging occurs, so-called "backwashing" can be performed by adding a method of reversing the pressure difference between the inside and outside of the porous tube for recovery.

[0013] Sixth, although requiring compressed air supply device, such as a conventional compressor or blower, water according to the present invention
Since it is a suction type using a head difference , such a device can be unnecessary. In addition, the porous chemical reaction liquid supply pipe can be easily unitized. By attaching joints to both ends of the transfer tube, or. By attaching a porous chemical reaction liquid supply pipe through a transparent plastic chemical reaction gas supply enclosure and attaching and sealing the contact between the through hole of the enclosure and the transfer pipe, the unit Body can be made. And the above. In the unit body, if the inner porous tube is made of ceramic, in particular, if the outer casing is made of a material having high mechanical strength such as plastic or metal, it can function as a reinforcing member, Breakage of the porous ceramic tube can be prevented. As a material for the porous tube,
In addition to a porous ceramic, a porous material such as a porous metal and a porous plastic can be used as appropriate. In any case, the pores of the porous portion need to be communicating holes.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below with reference to the drawings. Fig. 1 utilizes the head difference according to the present invention
1 is a schematic overall configuration diagram of a flue gas desulfurization device provided with a suction-type chemical reaction gas supply device. Exhaust gas emitted from thermal power plants and the like contains sulfurous acid gas, and if it is released into the outside air as it is, it will cause acid rain to fall. The removal apparatus is generally shown in a schematic configuration diagram as shown in FIG. 1, that is, firstly, flue gas from a thermal power plant or the like is introduced into an absorption tower device 20, where it is brought into contact with lime slurry. Due to the contact, the sulfurous acid gas reacts with the lime to generate and absorb calcium sulfite, which is further oxidized in the oxidizing device 21 to change into stable and useful gypsum. The above chemical reaction process formula is as follows. _{SO 2 + CaCO 3 = CaSO 3} + CO 2 to apply (absorption _{step) CaSO 3 + 1 / 2O 2} + 2H 2 O = CaSO 4 · 2H 2 O ( oxidation step) In this example apparatus to the oxidation step. That is, calcium sulfite (CaS) derived from the absorption tower 20
The O ₃ ) -containing fluid (chemical reaction liquid) is introduced into the absorption liquid storage layer 11 shown in FIG. 2, and from there through the chemical reaction liquid transfer pipe 4 to the suction type chemical reaction gas supply device 30 below. ,
Oxidize. In the suction-type chemical reaction gas supply device 30 utilizing the head difference shown in FIG. 2, the chemical reaction liquid (CaSO ₃ -containing liquid) transferred in the porous tube 1 contains fine particles from the pores of the porous tube 1. By oxidizing by sucking / supplying air (oxygen), calcium sulfite becomes gypsum in the porous tube 1, and gypsum (CaSO ₄ .2H ₂ O) passes through the fine-bubble-mixed chemical reaction liquid transfer tube 4 ′. It is taken out of the system. FIG.
In the figure, 1 is a porous tube made of ceramics, 2 is a chemical reaction gas (air) supply tube made of acrylic resin, 2 'is a flange, 3 is a chemical reaction gas inlet, and 4 is a chemical reaction solution (a solution containing calcium sulfite). The transfer tube, 4 'is a chemical reaction liquid transfer tube containing fine bubbles, 4 "is a flange, 5 is a fastener (bolt and nut), and 6 is a packing. Since a suction-type chemical reaction gas supply device consisting of a porous tube using a head difference is used , first, a large amount of pressure loss energy is not required unlike the conventional method using a vent tube, and the porous tube is not used. Due to the method of sucking the chemical reaction gas into the water through the gas, very small diameter bubbles are generated instead of the large diameter bubbles as in the case of the vent pipe, so the contact surface area between the bubbles and the chemical reaction solution But Large, and the incorporation efficiency into the liquid chemical reactant gas is greatly improved, and that may implement the chemical reaction with high efficiency.

The relationship between the pore diameter of the pores of the porous tube and the diameter of the generated fine bubbles is as shown in FIG. 7 as a result of the experiment.
That is, the distribution of the diameter of the generated microbubbles is about three times the distribution of the pore diameter of the porous tube. However, the measurement conditions in FIG. 7 are that the outer diameter of the porous tube is 13.5 mm and the inner diameter is 7 m.
m, the length is 120 mm, the average pore diameter is 22 μm,
The amount of flowing water in the chemical reaction liquid transfer pipe is 1.10 1 / sec.
It is. As a result of another measurement experiment, it was found that the diameter of the generated fine bubbles was about 2 to 4 times the average pore diameter of the porous tube.
In the vertical-type chemical reaction gas supply device, each member is easily disassembled and thus easy to assemble. The outer diameter of the ceramic porous tube 1 is the narrowest part of the acrylic resin chemical reaction gas supply tube 2. By keeping it almost the same as the inside diameter,
Both can be slid and inserted freely, which facilitates assembly and disassembly. In this configuration, the chemical reaction gas supply pipe 2 is supported as if sandwiching the porous pipe 1, and is advantageous because it also acts as a reinforcing member for reinforcing a fragile porous pipe such as a ceramic pipe. The vertical-type chemical reaction gas supply device of this configuration may be turned sideways to form a horizontal type, but in this case, the downstream side is located downstream of the hydraulic gradient line formed by the upstream and downstream pressure difference. Should be in a low state.

If a reducing tube is used, it can be used as it is as a horizontal type. Figure 3 shows the head difference
1 is a schematic cross-sectional view of one embodiment of a horizontal type chemical reaction gas supply device arranged in a horizontal position. In the figure, 1 is a porous pipe made of ceramics, 2 is a chemical reaction gas supply pipe made of acrylic resin, 2 'is a flange, 3 is a chemical reaction gas inlet, 4 is a downstream chemical reaction liquid transfer pipe, 4' is 4 is a flange, 5 is a fastener (bolt or nut), 6 is a packing, and 7 is a reducing tube which is also an upstream chemical reaction liquid transfer tube. When the chemical reaction liquid flows through the upstream constriction pipe 7 in the direction of the arrow, the negative pressure is maximized on the rear inner wall surface of the constriction pipe 7, and the chemical reaction from the chemical reaction gas inlet is performed in one part of the porous pipe. The gas passes through the porous tube wall and is supplied to the inside of the chemical reaction liquid as fine bubbles, and the narrowing angle of the retraction tube 7 is usually preferably about 10 to 30 degrees.

FIG. 4 is a conceptual diagram in which the present chemical reaction gas supplier is placed laterally and arranged in a siphon, and the chemical reaction gas is sucked from the porous tube as fine bubbles into the chemical reaction liquid. In the figure, reference numeral 30 denotes a chemical reaction gas supply according to the present invention,
Is a chemical reaction liquid transfer pipe, 11 is a chemical reaction liquid storage tank, 12 is a chemical reaction tank, HL is a hydrodynamic gradient line, and H is a head difference. In the figure, when the chemical reaction liquid is introduced from the storage tank 11 through the chemical reaction liquid transfer pipe 4 into the chemical reaction gas supply device 30, the outside air becomes fine bubbles due to the head difference H and the hydraulic gradient line HL. It is sucked and supplied into the chemical reaction liquid, and is supplied to the chemical reaction tank 12 arranged at a lower position through the chemical reaction liquid transfer pipe 4 ′ containing fine bubbles.

FIG. 5 is a schematic sectional view of another embodiment of a vertical type chemical reaction gas supply device utilizing a head difference . In the figure, the porous tube 1 is a gradually expanding tube, and the porous tube 1 is attached to the expanded portion. According to this example system,
Since the diameter of the lower portion of the chemical reaction liquid transfer tube is larger than that of the upper portion, the suction force at the expanded portion of the porous tube is further enhanced. In the figure, when the chemical reaction liquid drops from the upper chemical reaction liquid storage tank 11 and enters the gradually expanding pipe 8, the negative pressure increases on the inner wall surface of the porous pipe 1 of the gradually expanding pipe 8, and the chemical reaction gas is increased. The chemical reaction gas from the inlet passes through the porous tube 1 wall and is supplied as fine bubbles to the flowing chemical reaction liquid inside.

FIG. 6 is a schematic sectional view of another embodiment of a vertical type chemical reaction gas supply device utilizing a head difference . In this figure, a cylindrical chemical reaction gas supply device 9 having a porous tube 1 is provided inside a chemical reaction liquid supply tube 4. According to the present example system, the chemical reaction gas passes through the chemical reaction liquid transfer pipe 4, passes through the air guide pipe 10 connected to the chemical reaction gas supply device 9, and forms fine bubbles from the outer wall surface of the porous pipe 1. Then, it is sucked and supplied into the chemical reaction solution. The present invention can be applied not only to the flue gas desulfurization apparatus of the above chemical reaction example, but also to any other apparatus of a chemical reaction gas supply system by gas / liquid contact. For example, the present invention can be applied to an oxidation process apparatus for producing phenol and acetone by oxidizing cumene (isopropylbenzene). Further, the present invention is applicable to various enzyme reactions, for example, an alcohol fermentation apparatus using carbohydrate and yeast as raw materials.

As described above, in the present invention, the head difference is utilized.
Having adopted suction system by use porous tube, by sucking a chemical reaction gases from ceramics porous tube, a few 10μm several 100μm chemical reaction liquid flow pipe
It is possible to generate fine gas bubbles having a uniform diameter and uniform distribution, and to control the amount of the gas bubbles. In adjusting the generated bubbles, the amount of bubbles can be increased by increasing the negative pressure in the chemical reaction liquid transfer pipe or by increasing the air pressure in the chemical reaction gas supply pipe. This can be achieved by reducing the diameter of the communication hole of the porous tube.

[0021]

As has been described in detail in the embodiments and the like, according to the present invention, many excellent functions and effects as described below are exhibited. (1). ADVANTAGE OF THE INVENTION According to the chemical reaction gas supply apparatus which concerns on this invention, the pressure loss becomes considerably smaller than the conventional chemical reaction gas supply apparatus of the ejection type, and the reaction gas bubble generation efficiency in a chemical reaction liquid improves remarkably. (2). In the conventional jetting method, even if the diameter of the pores of an irregular porous tube made of ceramics or the like was reduced to about μm, the diameter of bubbles generated therefrom was on average about several mm,
According to the suction-type chemical reaction gas supplier according to the present invention, the average diameter of the generated bubbles can be reduced from several hundred μm to several tens μm. Therefore, the contact area between the chemical reaction solution and bubbles such as oxidizing gas can be extremely increased, and the residence time of the bubbles in the chemical reaction solution can be significantly increased. The amount of chemical reaction solution taken in can be dramatically increased. (3). By controlling the pressure of the chemical reaction gas sent to the chemical reaction liquid transfer pipe in the porous tube, the amount of air bubbles sucked can be adjusted without changing the flow rate of the chemical reaction liquid, and the amount of generated bubbles can be controlled. By,
High efficiency of chemical reaction can be achieved. (4). The pressure energy required for the suction of the chemical reaction gas from the porous tube only needs to be higher than the pressure loss head of the porous tube, and a very small pressure energy is sufficient, and energy saving operation is possible. (5). As the external chemical reaction gas is uniformly sucked near the inner wall of the porous tube, a gas-liquid flow is formed perpendicular to the wall toward the center of the tube. It acts in the direction of peeling off deposits and the like that are to adhere to the surface. As a result, clogging of the porous tube is less likely to occur. (6). There is no need for a compressed gas supply device such as a compressor or a blower as in the conventional system, and it is sufficient to simply secure the head difference. (7). The porous chemical reaction solution supply pipe section is easily unitized. For example, the porous chemical reaction solution supply pipe is attached to a transparent plastic reaction gas supply casing by penetrating the porous chemical reaction liquid supply pipe, and the through hole of the casing is provided. The unit body can be manufactured by bonding and sealing the contact part between the part and the transfer pipe. When the inner porous tube is made of ceramics in particular, if the outer casing is made of a material having high mechanical strength such as plastic or metal, it can function as a reinforcing member. The ceramic tube can be prevented from being damaged.

[Brief description of the drawings]

FIG. 1 is an explanatory view of the overall configuration of a chemical reaction device provided with a suction-type chemical reaction gas supplier utilizing a head difference according to the present invention.

FIG. 2 is a schematic cross-sectional view of one embodiment of a vertical type chemical reaction gas supply device utilizing a head difference of a chemical reaction device.

FIG. 3 is a schematic cross-sectional view of one embodiment of a horizontal-type chemical reaction gas supply device provided with a head difference .

FIG. 4 is a conceptual diagram in which a chemical reaction gas supply device is placed laterally and arranged in a siphon, and a chemical reaction gas is sucked as fine bubbles into a chemical reaction liquid from a porous tube.

FIG. 5 is a schematic cross-sectional view of another embodiment of a vertical chemical reaction gas supply device utilizing a head difference .

FIG. 6 is a schematic cross-sectional view of another embodiment of a vertical type chemical reaction gas supply device using a head difference .

FIG. 7 is a graph showing the relationship between the pore diameter of the pores of the porous tube and the diameter of the generated fine bubbles.

[Explanation of symbols]

1: Porous pipe made of ceramics, 2: Chemical reaction gas supply pipe made of acrylic resin, 2 ': Flange, 3: Chemical reaction gas inlet, 4: Chemical reaction liquid transfer pipe, 4': Chemical reaction mixed with fine bubbles Liquid transfer pipe, 4 ″ flange, 5: fastening tool (bolt, nut), 6: packing, 7: retraction pipe, 8: regression pipe 9: cylindrical chemical reaction gas supply, 10: air guide pipe, 11 :
Chemical reaction solution storage tank, 12: chemical reaction tank, 20: absorption tower,
21: Oxidizer, 30: Chemical reaction gas supplier, 56: Suction type chemical reaction gas supplier, HL: Hydrodynamic gradient line, H: Head difference

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-4528 (JP, A) JP-A-55-1808 (JP, A) JP-A-63-137742 (JP, A) JP-A-51- 124858 (JP, A) JP-A-54-153368 (JP, A) JP-A-56-17625 (JP, A) JP-A-2-207828 (JP, A) Full-scale application 49-79647 (JP, U) 55-122896 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01J 10/00-10/02 B01J 19/00-19/32 B01D 53/34 B01F 1 / 00-5/26 C02F 3/14-3/26

Claims (8)

(57) [Claims] 1. A porous chemical reaction liquid flow tube is exposed to the chemical reaction gas in the atmosphere, and becomes comprise Do <br/> Ru suction type reaction gas supplier arranged to provide a water head difference A chemical reaction device characterized by the above-mentioned. 2. A chemical, wherein the chemical reaction gas supply pipe porous chemistry liquid flow tube middle side of, with a suction-type reaction gas supplying device formed by placement provided water head difference Reactor. 3. A suction-type chemical reaction gas supply device provided with a porous chemical reaction gas supply pipe disposed inside a chemical reaction liquid transfer pipe provided with a head difference. And a chemical reaction device. 4. A chemical reaction apparatus according to any one of claims 1 to 3, wherein the pores of the porous tube is irregular passage. 5. The chemical reaction according to claim 1, wherein the porous chemical reaction liquid transfer pipe and / or the porous chemical reaction gas supply pipe is a porous ceramic pipe. apparatus. 6. The chemical reaction apparatus according to claim 1, wherein the porous chemical reaction liquid transfer pipe and / or the porous chemical reaction gas supply pipe are porous metal pipes. . 7. The communicating hole of the porous chemical reaction liquid transfer pipe and / or the porous chemical reaction gas supply pipe has a diameter of 500 μm.
The chemical reaction device according to any one of claims 1 to 6, wherein: 8. A chemical reaction gas supply chamber in the form of a tube or a housing is provided around a porous chemical reaction liquid supply pipe. The chemical reaction device according to claim 1.