JPH0315195Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an apparatus for chemically cleaning the inner surface of a tank, particularly a spherical tank, for storing chemical substances.

[Conventional technology]

Generally, chemical cleaning is performed to prevent rust inside a tank for storing chemical substances during tank construction or periodic inspection.In the past, the spray cleaning method, which is often used as a method for chemically cleaning tanks, Devices that sprinkle liquid while rotating, such as rotating jetters or sprinklers, are often used because they are simple and easy to install.

[Problem that the invention attempts to solve]

However, in these conventional devices, the contact angle when the spray liquid reaches the wall surface varies, and the liquid that reaches the wall surface is reflected and does not spread sufficiently, and the action is unstable. The cleaning liquid acts intermittently and the flow of cleaning liquid on the wall is not constant. Because of these two points, the cleaning action on the inner wall surface of the tank becomes unstable and a sufficiently good effect cannot be obtained, and rust remains on the wall surface or new rust occurs.

Therefore, it is difficult to completely remove the rust by spray cleaning, and there are problems in cleaning the inner wall surfaces of storage tanks, such as ethylene oxide monomer, where the presence of iron rust is inconvenient. Ta.

The present invention eliminates these conventional drawbacks and more accurately cleans the inner wall surface of the storage tank, that is, forms an even, steady, and stable falling film of cleaning liquid along the inner wall surface of the tank, and cleans the inner wall surface of the tank more accurately. The purpose is to provide an easy-to-handle and economical cleaning device that can prevent rust by blocking the oxygen contained in the gas from the inside of the tank and constantly supplying a cleaning liquid with a constant property to the inside surface of the tank. It is something.

[Means for solving problems]

The present invention is a cleaning device that performs chemical cleaning of a tank by spraying cleaning _liquid onto the inner wall surface of the tank. A rotatable shaft tube 3 is rotatably provided, and a communication support tube 4 for introducing liquid is provided which is radially connected and communicated with the rotary shaft tube 3,
An arc-shaped pipe having a branch pipe 5 ₁ and a flange 5 ₂ at the tip of the communication support pipe 4 is connected by the branch pipe 5 ₁ , and assembled in a ring shape in the tank at the connecting surface of the flange 5 ₂ . providing a ring pipe 5 which is connected and extends closely and continuously along the inner wall surface of the tank;
A tank cleaning device characterized in that a large number of nozzles 6 are provided outside the ring pipe 5 and open toward the inner wall surface of the tank, and the rotating shaft pipe 3 is connected to a drive motor 8 through a transmission mechanism 7. be.

〔Example〕

An example in which the present invention is applied to a spherical tank will be explained with reference to the drawings.The cleaning liquid injected into the spherical tank 1 forms a steady and stable falling liquid film on the inner wall surface of the tank. From the manhole 1 ₁ on the top of tank 1 to tank 1
A rotary shaft tube 3 is rotatably provided on a fixed shaft tube 2 for supplying cleaning liquid introduced into the interior, and a communication support tube 4 for guiding liquid is provided to communicate with the rotation shaft tube 3. Arc-shaped pipes each having a branch pipe 5 ₁ and a flange 5 ₂ at the tip of the pipe 4 are connected by the branch pipe 5 ₁ , and assembled and connected within the tank in an annular shape at the connecting surface of the flange 5 ₂ . , a ring pipe 5 extending in an annular shape is provided close to the inner wall surface of the upper part of the tank, a large number of nozzles 6 are provided outside the ring pipe 5 and open toward the inner wall surface of the tank, and the rotation axis pipe 3
is connected to a drive motor 8 through a transmission mechanism 7. That is, in order to form a steady and stable falling liquid film of cleaning liquid on the inner surface of the spherical tank, the liquid must be injected at a low pressure of about 0.1 Kgf/cm ² at the upper part of tank 1, close to the inner wall surface of the tank. However, in order to obtain an even falling film of cleaning liquid all around the tank, it is necessary to distribute the liquid between the rotating shaft pipe 3 located in the center of the tank and close to the inner surface of the tank. A plurality of communication support pipes 4, which serve as both pipes and communication support pipes, are arranged _radially .
5 It is connected and supported by ₁ . Further, the ring pipe 5 is composed of divided arc-shaped pipes connected at a connecting surface with a flange 5 ₂ , and is assembled in a ring shape inside the tank so that it can be deployed along the inner surface of the tank 1. It is not limited to this, but it can also be provided in multiple stages of two or more stages.

Note that the rotation shaft pipe 3 is a plurality of branch pipes 3 ₁
It is rotatably mounted on the fixed shaft tube 2 via a metal bearing 15 and a thrust bearing 11 using a pipe joint. The transmission mechanism 7 is a gear mechanism, which is meshed with a pinion ₇₁ directly connected to the motor 8, and is driven to rotate.

12 in the figure fixes the thrust bearing 11 with a tightening nut.

In the embodiment of the present invention, the diameter of the annular part of the ring pipe 5 is 5.500 mm, the diameter of this part of the pipe is 80 mm, and the connection with the center part is to connect three connecting support pipes 4 at equal angles of 120 degrees. The diameter of this communication support pipe 4 was 100 mm. Fixed side shaft tube 2 and rotating side shaft tube 3 in the center
Both had a diameter of 150 mm and were fixed to the manhole ₁₁ at the top of the spherical tank 1. The rotational speed of the ring was approximately 1/3 to 1/5 rpm, and the distance from the nozzle surface of the ring pipe 5 to the inner wall of the tank was 150 to 200 mm, and the gear was driven by a motor 8 with a speed reducer. Since the inside of the spherical tank is hot and humid at approximately 70°C, the motor 8 was housed in a sealed case, and cooling air was supplied and exhausted from the outside to provide cooling and moisture protection. In addition,
The installation pitch of the injection nozzle 6 provided in the annular part is approximately
It was 200mm.

In this case, the cleaning liquid has a hydraulic pressure range of 0.05 to 0.2 Kgf/cm ² and a pressure range of 1.8 to 3.6 m ^{3 /} cm at the horizontal plane in the center of the tank.
When the liquid is supplied in the liquid flow range of m/h, the thickness of the liquid film near the cleaning liquid injection part is approximately 1.6 to 2 mm, and the thickness of the liquid film is uniform and steady at the maximum diameter part of the center of the spherical tank to approximately 0.5 to 0.7 mm. A consistent and stable falling film of cleaning solution was obtained.

A small amount of the cleaning liquid containing ammonium citrate is stored at the bottom of the spherical tank 1, and is set so as to be circulated to the manhole ₁₁ through a piping 9 including a pump (not shown). The cleaning liquid is sprayed onto the inner wall surface of the tank from the spray nozzle 6 of the ring pipe 3 which rotates through the pipe 7.

It is preferable that a flow meter and a pressure gauge be provided in the piping 9 to be used as a detection unit capable of adjusting the flow rate and pressure range as described above. As the adjustment means, known means such as valve adjustment, pump adjustment, and other adjustment means are selected and used.

Furthermore, in order to enhance the cleaning effect, the cleaning liquid is heated, and this heating is performed by a method such as electric heating or injection of superheated steam.

Although the transmission mechanism 7 and the motor 8 are arranged inside the tank to rotate the rotation shaft tube 3, they can also be arranged outside the tank.

[Effect of idea]

This invention is based on the manhole 1 located at the top of tank _1.
A rotary shaft pipe 3 is rotatably provided to a fixed shaft pipe 2 for supplying cleaning liquid introduced into the tank 1 from the tank 1, and a connecting support pipe 4 for introducing liquid is connected to the rotary shaft pipe 3. A ring pipe 5 that follows an annular shape is provided close to the inner wall surface of the upper part of the tank, and a large number of nozzles 6 that open toward the inner wall surface of the tank are provided on the outside of the ring pipe 5, and the rotation axis pipe 3 is transmitted. By communicating with the drive motor 8 through the mechanism 7, the spray nozzle that flows down the cleaning liquid from the upper part of the spherical tank to form an even, steady, and stable liquid film over the entire circumference of the inner wall of the tank is accurately aligned along the inner surface of the tank. Moreover, since the ring tube can be rotated under stable conditions using the connecting support tube, it is easy to operate, does not require large driving force, and the cleaning effect can be significantly improved. Safe chemical cleaning can be performed without increasing the size of the cleaning equipment. This is possible and can greatly reduce the economic burden.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which FIG. 1 is a longitudinal sectional view, FIG. 2 is a plan view, and FIG. 3 is a partially enlarged cutaway side view. 1...tank, 1 ₁ ...manhole, 2...fixed axis pipe, 3...rotating axis pipe, 3 ₁ ...branch pipe, 4...
...Connection support pipe, 5...Ring pipe, 5 ₁ ...Branch pipe,
6... Injection nozzle, 7... Transmission mechanism, 8... Drive motor, 9... Connection pipe, 11... Thrust bearing,
12... Tightening nut.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a cleaning device that performs chemical cleaning of a tank by spraying cleaning liquid onto the inner wall surface of the tank, a cleaning liquid supply that is introduced into the tank 1 from a manhole ₁₁ located at the top of the tank 1. A rotary shaft tube 3 is rotatably provided in a fixed shaft tube 2 for use, and a communication support tube 4 for introducing liquid is provided which is radially connected and communicated with the rotation shaft tube 3. Arc-shaped pipes each having a branch pipe 5 ₁ and a flange 5 ₂ at their tips are connected by the branch pipe 5 ₁ , and assembled and connected within the tank in an annular manner at the connection surface of the flange 5 ₂ , and the tank A ring pipe 5 is provided that runs closely and continuously along the inner wall surface, and a large number of nozzles 6 that open toward the inner wall surface of the tank are provided on the outside of the ring pipe 5. A tank cleaning device characterized by contacting 8. (2) The rotating shaft pipe 3 is a hollow shaft, and is connected to the communication support pipe 4 by protruding a plurality of branch pipes 3 ₁ , and the pipe is a pipe to which the cleaning liquid is fed under pressure by a pump. Fixed shaft tube 2 detachably connected to 9
A cleaning device according to claim 1, which is connected to a utility model.