JP2011092820A - Deodorizing method for tank with residual odorous gas - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for efficiently deodorizing a tank in which odorous gas remains. <P>SOLUTION: This deodorizing method includes processes of: connecting an opening 12a of the tank 12, in which the odorous gas 11 remains and which provides the opening 12a and a valve 13 closing the opening 12a, to the upper end 21a of the duct 21 of a deodorizer 20, which provides the vertically extended duct 21 and a plurality of spray nozzles disposed in the duct along the length direction of the duct, via a pipe 45; generating fine particles of ozone-containing water by downwardly spraying the ozone-containing water from the respective spray nozzles; and deodorizing the tank inside, while leading the odorous gas 11 into the duct 21 by opening the valve 13 of the tank 12, by bringing the odorous gas going down in the duct into contact with the fine particles of ozone-containing water sprayed downwardly in the tank for oxidation decomposition. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for deodorizing the inside of a tank in which odorous gas remains.

  The tank that stores the liquid chemical is cleaned, for example, when another type of liquid chemical is stored. The tank is cleaned after the chemicals contained in the tank are extracted. However, when odorous chemicals are stored in the tank, a large amount of odorous gas may remain in the tank from which the chemicals are extracted. For this reason, when the valve provided in the opening is opened during cleaning, odorous gas remaining in the tank is released, and the odor becomes a problem.

  It is conceivable to introduce ozone gas into such a tank and decompose and deodorize odorous gas by the strong oxidizing action of ozone gas. However, it is difficult to decompose and deodorize the odorous gas in the tank in a short time unless ozone gas is uniformly diffused in the tank. Moreover, when ozone gas is introduced into the tank, odorous gas that has not been sufficiently deodorized by the introduction of ozone gas may overflow from the tank, and the odor may become a problem.

  Japanese Patent Laid-Open No. 2004-133867 has conventionally known a device that deodorizes by contacting an odorous gas and ozone gas. However, the conventional device cannot perform sufficient deodorization because the odorous gas is hardly oxidized by ozone gas. In order to solve this problem, there has been disclosed a deodorizing apparatus for bringing an odorous gas into contact with ozone water. The deodorization apparatus described in the same document is composed of a tank having an odorous gas supply pipe on the side, an exhaust pipe on the upper side, and a water-containing pipe for ozone-containing water disposed above the tank. ing. In this deodorizing device, the odorous gas flowing upward in the tank is brought into contact with ozone water flowing downward in the tank from the water spray pipe to oxidize and remove (deodorize) the odorous gas.

  Patent Document 2 discloses an ozone deodorizing apparatus including a deodorizing tower having an odorous gas introduction portion below and a discharge pipe at the top. Above the odorous gas introduction part inside the deodorizing tower, a nozzle for spraying ozone water is installed. In this deodorization apparatus, the odorous gas flowing upward from the odorous gas introduction part inside the deodorization tower toward the discharge pipe is brought into contact with fine particles of ozone water that is jetted from the nozzle and flows downward, thereby causing the odor. Deodorizing sexual gas.

JP-A-10-249141 JP 2004-66135 A

  The subject of this invention is providing the method of deodorizing efficiently the atmosphere inside the tank in which odorous gas remains.

This invention exists in the deodorizing method inside the tank with which the odorous gas which consists of the process of following (1)-(3) remains.
(1) An opening in which odorous gas remains inside and an opening of a tank having a valve closing the opening, a duct extending in the vertical direction, and an inside of the duct are arranged along the length direction. The process of connecting mutually the upper end part of the said duct of a deodorizing apparatus provided with the provided several injection nozzle through a tubular body.
(2) A step of generating fine particles of ozone-containing water by spraying ozone-containing water downward from each of the spray nozzles.
(3) Ozone which is blown downward into the inside of the duct by opening the valve of the tank and deriving the odorous gas to the duct, thereby A step of deodorizing the inside of the tank by bringing it into contact with fine particles of water to cause oxidative decomposition.

The preferable aspect of the deodorizing method of this invention is as follows.
1) The duct is provided with an extension portion that is folded back at the lower end portion and extends upward, and a plurality of injection nozzles are disposed along the length direction inside the extension portion. Ozone-containing water fine particles are generated by jetting ozone-containing water downward from the spray nozzle, and the odor proceeds upward in the extension without oxidative decomposition in the step (3). The oxidative gas is brought into contact with fine particles of ozone-containing water jetted downward into the extension portion to be oxidatively decomposed.
2) The tank is a tank of a tank container or a tank of a tank car.
3) The odorous gas is hydrogen sulfide, methyl mercaptan, methyl sulfide, methyl disulfide, formaldehyde, acetaldehyde, acrolein, propyl aldehyde, acetic acid, butyric acid, propionic acid, ammonia, methylamine, trimethylamine, or crotonaldehyde. .

  In the present specification, “downward” indicating the direction in which the ozone-containing water is jetted refers to the velocity of the ozone-containing water jetted from the nozzle and is downward along the length direction of the duct or its extension. It means the direction in which the velocity component is generated, that is, it includes a diagonally downward direction (a direction inclined within a range of ± 85 degrees, preferably ± 60 degrees with respect to the length direction of the duct or its extension). .

  By carrying out the method of the present invention, the odorous gas remaining in the tank can be efficiently decomposed and deodorized.

It is a figure which shows each structural example of the deodorizing apparatus preferably used when implementing the deodorizing method inside the tank of this invention, and the tank of deodorizing object. It is a right view which expands and shows the site | part shown with the code | symbol A of the deodorizing apparatus 20 of FIG. However, the duct 21 is shown as a cross section. It is a figure which shows the structure of the apparatus which can be used especially advantageously for the production | generation of the ozone containing water supplied to the deodorizing apparatus 20 of FIG.

  First, a tank to be deodorized by the method of the present invention and an apparatus used for deodorization will be described with reference to the accompanying drawings.

  FIG. 1 is a diagram showing a configuration example of each of a deodorizing apparatus and a tank to be deodorized that are preferably used when carrying out the deodorizing method of the present invention. FIG. 2 is an enlarged right side view of the portion indicated by the symbol A of the deodorizing apparatus 20 of FIG. However, the duct 21 is shown as a cross section.

  The odorous gas 11 remains in the tank 12 to be deodorized. An opening 12 a is provided at the top of the tank 12. A valve 13 is provided in the opening 12a.

  The deodorizing apparatus 20 is provided with a tube 41 for supplying ozone-containing water. An arrow 91 written in FIG. 1 indicates the direction in which the ozone-containing water flows.

  Tubular bodies 42 and 43 extending in the vertical direction are connected to the tubular body 41 through branch pipes 51. The tube body 42 includes a plurality of branch pipes 52 (total of six in the configuration of FIG. 1) along the length direction. Similarly, the pipe body 43 includes a plurality of branch pipes 53 (a total of five in the configuration shown in FIG. 1) along the length direction thereof.

  A duct 21 extending in the vertical direction is disposed on the rear side of the tube body 42 in FIG. Then, each branch pipe 52 of the pipe body 42 is connected to a pipe body 44 extending to the inside of the duct 21 as shown in FIG. An injection nozzle 22 is provided at the tip of the tube body 44. As described above, a plurality of (6 in total, in the configuration of FIG. 1) injection nozzles 22 are arranged along the length direction of the duct 21 inside the duct 21.

  Accordingly, when ozone-containing water is supplied to the tube body 41, the ozone-containing water is provided at the tip of each tube body 44 through the branch tube 51, each branch tube 52 of the tube body 42, and each tube body 44. Injected from the injection nozzle 22 toward the inside of the duct 21. Thereby, fine particles 29 of ozone-containing water are generated inside the duct 21.

  The duct 21 includes an extension portion 31 that is folded back at the lower end portion 21b and extends upward. The extension portion 31 is disposed on the rear side of the tube body 43 in FIG. As in the case of each branch pipe 52 of the pipe body 42, each branch pipe 53 of the pipe body 43 has an injection nozzle (not shown) via a pipe body extending to the inside of the extension portion 31 of the duct 21. Is connected. As described above, a plurality of spray nozzles (five in total in the configuration of FIG. 1) are arranged along the length direction of the extension portion 31 inside the extension portion 31 of the duct 21.

  Accordingly, when ozone-containing water is supplied to the pipe body 41, the ozone-containing water passes through the branch pipe 51, each branch pipe 53 of the pipe body 43, and the pipe body extending to the inside of the extension portion 31, and this pipe body. From the spray nozzle provided at the tip of the nozzle 31, the spray is sprayed downward inside the extension portion 31. Thereby, fine particles of ozone-containing water are generated in the extension portion 31.

  The upper end 21 a of the duct 21 is connected to the opening 12 a of the tank 12 through the tube body 45. The lower end portion 21 b of the duct 21 is connected to the pump 61 via the extension portion 31 and the tube body 46.

  Then, by opening the valve 13 provided in the tank 12, the odorous gas 11 remaining in the tank 12 can be led out to the duct 21 through the pipe body 45. The odorous gas 11 can be led out to the duct 21 by opening the valve 13 when the internal pressure of the tank 12 is high. At this time, the pump 61 can be operated to assist the odorous gas 11 being led out. When the internal pressure of the tank 12 is low, the odorous gas 11 is derived mainly using the pump 61. When the odorous gas 11 is derived, it is preferable to open a valve (not shown) provided in another opening provided in the tank 12.

  Next, the deodorizing method of the present invention will be described.

The method for deodorizing the inside of a tank according to the present invention comprises performing the following steps (1) to (3) in this order.
(1) In the inside of the opening part 12a of the tank 12 provided with the valve | bulb 13 which has obstruct | occluded the opening part 12a and the opening part 12a which the odorous gas 11 remains inside, the duct 21 extended in an up-down direction, and the inside of the duct 21 The process of connecting the upper end part 21a of the duct 21 of the deodorizing apparatus 20 provided with the some injection nozzle 22 arrange | positioned along the length direction mutually via the pipe body 45. FIG.
(2) A step of generating fine particles 29 of ozone-containing water by jetting ozone-containing water downward from each of the jet nozzles 22.
(3) While the valve 13 of the tank 12 is opened and the odorous gas 11 is led out to the duct 21, the odorous gas traveling downward in the duct 21 is thereby moved downward into the duct 21. A step of deodorizing the inside of the tank 12 by bringing it into contact with fine particles 29 of ozone-containing water sprayed toward the surface to cause oxidative decomposition.

  In the deodorizing method of the present invention, the fine particles 29 of ozone-containing water traveling downward in the duct 21 are generated in each of the plurality of injection nozzles 22 disposed along the length direction in the duct 21. In the duct 21, the direction in which the odorous gas travels (the direction indicated by the arrow 92a) and the direction in which the ozone-containing water fine particles 29 travel (the direction indicated by the arrow 92b) are the same (downward in the figure). The main feature is that it is set in the direction of the side. The above-mentioned “directions identical to each other” means that each of the odorous gas and the fine particles of ozone-containing water has a downward velocity component along the length direction of the duct 21.

  The odorous gas remains at a high concentration in the tank from which the odorous liquid chemical is extracted. Therefore, it is necessary to deodorize the tank in which the odorous gas remains efficiently (in a short time) and without releasing the odorous gas to the outside.

  When the ozone-containing water particles are brought into contact with the odorous gas inside the duct 21, if the direction in which the odorous gas advances and the direction in which the ozone-containing water particles advance are set to be opposite to each other, the odor Although the reactive gas and the fine particles of ozone-containing water are sufficiently mixed, it is difficult to efficiently oxidize and decompose the odorous gas because the contact time between the two is short.

  In the deodorizing method of the present invention, the direction in which the odorous gas advances and the direction in which the fine particles 29 of the ozone-containing water advance are set in the same direction inside the duct 21. For this reason, fine particles of ozone-containing water can be brought into contact with the odorous gas for a long time.

  On the other hand, as the odorous gas advances downward in the duct 21, the oxidative decomposition of the odorous gas proceeds by contact with the fine particles of the ozone-containing water. And if the deodorizing apparatus 20 is a structure provided with an injection nozzle only in one place of the up-down direction inside the duct 21, ozone contained in the fine particles of ozone-containing water is consumed as the oxidative decomposition proceeds. The amount of ozone necessary for the oxidative decomposition of the odorous gas is insufficient below the duct 21. Since the deodorizing apparatus 20 used in the method of the present invention includes a plurality of injection nozzles 22 along the length direction inside the duct 21, the ozone-containing water is injected from each of the injection nozzles 22, thereby the duct 21. A sufficient amount of ozone can be supplied to the lower part of the surface.

  For the above reasons, by carrying out the deodorizing method of the present invention, it is possible to efficiently oxidize and decompose even when a large amount of odorous gas remains in the tank.

  The deodorizing method of the present invention can efficiently deodorize the inside of the tank in which the odorous gas remains without extracting the odorous gas directly to the outside of the tank.

  It is preferable that the number of injection nozzles disposed along the length direction of the duct 21 is in the range of 2 to 20 (particularly 3 to 10).

  In the deodorizing method of the present invention, as shown in FIG. 1, the duct 21 is provided with an extension portion 31 that is folded back at the lower end portion 21 b and extends upward, and the extension portion 31 also extends along the length direction. A plurality of injection nozzles are provided, and ozone-containing water fine particles are generated by injecting ozone-containing water downward from the respective injection nozzles of the extension, and the step (3), that is, the duct Ozone-containing water fine particles jetted downward in the extension portion 31 with odorous gas that progresses upward in the extension portion 31 without being oxidatively decomposed in the deodorizing step inside 21 It is preferable to make it oxidatively decompose by contacting with the.

  When the fine particles of ozone-containing water are brought into contact with the odorous gas inside the extension portion 31 of the duct 21, the direction in which the odorous gas advances (93a) and the direction in which the fine particles of ozone-containing water advance (arrow 93b) are opposite to each other. The orientation is set. Note that the term “opposite directions” means that the odorous gas has an upward velocity component along the length direction of the extension, and the ozone-containing water fine particles have a downward velocity component. Means that

  With such a setting, even if a minute amount of odorous gas remains after the deodorizing step inside the duct 21, the odorous gas is finely divided into ozone-containing water in the extension portion 31. And oxidative decomposition, and further deodorization of odorous gas is realized.

  The number of spray nozzles disposed along the length direction of the extension 31 is preferably in the range of 2 to 20 (particularly 3 to 10).

  In addition, examples of tanks to be deodorized by the deodorizing method of the present invention include tanks of tank containers or tanks of tank cars. These tanks are frequently subjected to replacement of liquid chemicals in the tanks and cleaning of the tanks for that purpose. Odorous liquid chemicals are transported by these tanks, and after the odorous liquid chemicals are extracted from the tanks for replacement of the chemicals inside the tanks, odorous gas remains by the method of the present invention. Deodorize the inside of the tank. As a result, the deodorization inside the tank is completed in a short time without releasing the odorous gas to the outside. For this reason, the cleaning of the inside of the tank performed next can be started promptly in a good environment without odor. Therefore, the transport efficiency of liquid chemicals by these tanks (tank operation rate) is improved.

  In the deodorizing method of the present invention, the odorous gas remaining inside the tank is hydrogen sulfide, methyl mercaptan, methyl sulfide, methyl disulfide, formaldehyde, acetaldehyde, acrolein, propyl aldehyde, acetic acid, butyric acid, propionic acid, ammonia, methylamine. , Trimethylamine, or crotonaldehyde gas can be used particularly advantageously.

  In addition, the valves 32 and 33 provided at the lower ends of the pipes 42 and 43 of the deodorizing apparatus 20 in FIG. 1 respectively discharge the air contained therein when introducing ozone-containing water into the pipes. Used for. By checking the internal pressure of each of these tubes 42, 43 with each of the pressure gauges 62, 63, the amount of ozone-containing water supplied to the tube 41 is increased or decreased to be injected from each of the injection nozzles. The amount of ozone-containing water can be adjusted to a predetermined amount.

  Further, the ozone-containing water sprayed into the duct 21 and its extension 31 flows into the bottom of the extension 31 as drainage after being used for deodorizing odorous gas. A tube body 47 having a transparent tube 47 a at the center is provided below the outer surface of the extension portion 31. The upper and lower ends of the tube body 47 are open inside the extension portion 31. For this reason, when the amount of drainage in the extension portion 31 increases, the drainage flows into the transparent tube 47 a of the tube body 47. Therefore, by observing the liquid level of the drainage from the outside of the transparent tube 47a, it is possible to confirm an increase in the amount of drainage inside the extension portion 31. When the amount of drainage increases inside the extension 31, drainage is extracted by opening the valve 34 connected to the bottom of the extension 31 via the tube 46.

  On the other hand, a mesh body 28 for preventing discharge of fine particles of ozone-containing water to the outside is provided above the extension portion 31 of the duct 21. The net body 28 has a function of capturing fine particles of ozone-containing water that travels upward in the extension portion 31 by riding on the flow of the odorous gas and drops it as water droplets from the central portion thereof.

  FIG. 3 is a diagram showing a configuration of an apparatus (ozone-containing water generating apparatus) that can be used particularly advantageously for generating ozone-containing water supplied to the tube body 41 of the deodorizing apparatus 20 of FIG.

  The ozone-containing water generating device 70 in FIG. 3 includes a container 72 having a pipe 71 connected to supply water (for example, tap water) as a raw material for ozone-containing water to the top. The pipe body 73 provided in the container 72 is connected to the side surface of the container 72 with both ends thereof spaced apart from each other. The pipe body 73 is provided with a pump 74. The pipe body 73 is branched into two branch pipes 73a and 73b on the way. The branch pipe 73a is provided with a valve 75, and the branch pipe 73b is provided with an injector 76 and a pressure gauge 77. An ozone gas generator 79 is connected to the injector 76 via a tube 78. The ozone gas generator 79 is connected to an oxygen cylinder 81 containing oxygen as a raw material for ozone gas via a tube 80. By adjusting the opening amount of the valve 75 of the branch pipe 73a, the pressure of water flowing inside the branch pipe 73b can be increased or decreased, and the amount of ozone gas dissolved in the water can be adjusted.

  By operating the pump 74 of the ozone-containing water generating apparatus 70, the water inside the container 72 is extracted from one end of the pipe body 73 and flows into the container 72 again from the other end. At the same time, the ozone gas generator 79 is operated to generate ozone gas in the ozone gas generator 79 using the oxygen gas stored in the oxygen cylinder 81 as a raw material. This ozone gas is injected into the water flowing through the branch pipe 73b by the injector 76 and dissolved. The water in which the ozone gas is dissolved flows into the container 72, and the concentration of ozone gas in the water inside the container 72 gradually increases.

  And the water (ozone containing water) which the ozone gas produced | generated inside the container 72 melt | dissolved is supplied to the pipe body 41 of the deodorizing apparatus of FIG. Note that the pipe 83 provided in the container 72 is configured to remove the ozone-containing water for cleaning from the container 72 when the inside of the tank (FIG. 1: 12) where deodorization is completed is further washed with ozone-containing water. Used to extract.

  Instead of the ozone-containing water generating device 70 of FIG. 3, a known ozone-containing water generating device can also be used.

DESCRIPTION OF SYMBOLS 11 Odorous gas 12 Tank 12a Opening part 13 Valve 20 Deodorizing apparatus 21 Duct 21a Upper end part of duct 21b Lower end part of duct 22 Injection nozzle 28 Net body 29 Fine particle of ozone containing water 31 Duct extension part 32, 33, 34 Valve 41 , 42, 43, 44, 45, 46, 47 Tube 47a Transparent tube 51, 52, 53 Branch tube 61 Pump 62, 63 Pressure gauge 70 Ozone-containing water generator 71 Tube 72 Container 73 Tube 73a, 73b Branch tube 74 Pump 75 Valve 76 Injector 77 Pressure gauge 78 Tubing 79 Ozone gas generator 80 Tubing 81 Oxygen cylinder 82 Pump 83 Tubing 91 Arrows 92a and 93a indicating the direction in which the ozone-containing water flows 92b 93b Arrow indicating the direction in which fine particles of ozone-containing water travel

Claims (4)

Deodorization method inside the tank where odorous gas consisting of the following steps remains:
(1) An opening in which odorous gas remains and an opening of a tank provided with a valve closing the opening, a duct extending in the vertical direction, and the inside of the duct along the length direction Connecting the upper ends of the ducts of a deodorizing apparatus having a plurality of spray nozzles arranged in a line to each other through a pipe;
(2) a step of generating fine particles of ozone-containing water by injecting ozone-containing water downward from each of the injection nozzles; and (3) while opening a valve of the tank and deriving odorous gas to the duct. Thus, the inside of the tank is deodorized by bringing the odorous gas traveling downward in the duct into contact with fine particles of ozone-containing water jetted downward in the duct to oxidize and decompose. Process.   The duct includes an extension portion that is folded back at the lower end portion and extends upward, and a plurality of injection nozzles are disposed along the length direction inside the extension portion. Ozone-containing water fine particles are generated by jetting ozone-containing water downward from the nozzle, and the odor proceeds upward in the extension without oxidative decomposition in the step (3). The method according to claim 1, wherein the oxidative gas is brought into contact with fine particles of ozone-containing water jetted downward into the extension and is oxidatively decomposed.   The method according to claim 1, wherein the tank is a tank of a tank container or a tank of a tank truck.   The odorous gas is a gas of hydrogen sulfide, methyl mercaptan, methyl sulfide, methyl disulfide, formaldehyde, acetaldehyde, acrolein, propyl aldehyde, acetic acid, butyric acid, propionic acid, ammonia, methylamine, trimethylamine, or crotonaldehyde. The method according to 1.

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