JP2010121799A - Furnace-wall structure of plant device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a furnace-wall structure of a plant device capable of easily separating extraneous matters attached to an inner wall surface of the plant device when an operation is stopped for periodic inspection and the like. <P>SOLUTION: In this furnace wall structure of the plant device in which the extraneous matters such as ash, fly ash and clinker attach to the inner wall surface comprising a metallic wall of the plant device, the inner wall surface is coated in advance with a coating agent chemically changeable to a state separatable from a boundary to the metallic wall by moistening the inner wall surface comprising the metallic wall of the plane device with the water, and then the water is applied to the extraneous matters attached to the coating film formed of the coating agent, thus the extraneous matters can be separated from the inner wall surface of the plant device. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a furnace wall structure of plant equipment, and more particularly to a furnace wall structure of plant equipment configured to be able to peel off deposits such as ash, fly ash, and clinker attached to an inner wall surface made of a metal wall of plant equipment. Is.

  In plant equipment such as a thermal power plant and a waste incineration plant, deposits such as ash, fly ash, and clinker adhere to the wall surface of the plant equipment during operation. For example, in a thermal power plant, a coal-fired boiler is often used to generate high-temperature and high-pressure steam. Combustion ash coming out of the boiler consists of fly ash and clinker ash. Solidified, drained and crushed into granules. Although both are discarded, since most of the components are silica and alumina, they have recently been increasingly used as raw materials for fly ash cement.

  The above clinker ash (hereinafter referred to as clinker) is attached to the furnace wall 1 at the top of the furnace and the element portion 23 such as a main steam pipe and a reheater pipe during operation in the coal fired boiler 20 shown in FIG. (Reference numeral 15 in FIG. 3). For this reason, at the time of regular inspection, it is necessary to remove the clinker 15 that has become attached and solidified and enlarged before putting an inspection worker inside the coal-fired boiler 20.

  The most common method for removing the clinker ash described above is a method of performing soot blow using the soot blower 21. The soot blower 21 is generally a device that blows high-pressure steam onto the surface of the boiler water pipe during operation of the boiler, and blows off deposits on the surface of the boiler water pipe by the fluid force. Further, removal by water discharge from the viewing window 22 and removal by a deslagger are also known.

Furthermore, when removing ash, clinker, etc. that have been used in the past, workers should enter the boiler and use tools to strip off ash, clinker, etc., apply shot blasting, and wash with water. However, since it is necessary to lie down in the narrow gap between the boiler water tube group in the vertical direction and to perform the work and to protect against exposure to dioxins, it is a heavy burden on the workers. It was over.
Therefore, the above-described conventional removal method has a problem in safety, and the clinker 15 cannot be sufficiently removed or takes a long time. It has become.

  As a prior art of such a clinker removal method, for example, Patent Document 1 (Japanese Patent Application Laid-Open No. 2004-202485) discloses ash, fly ash, and the like attached to plant equipment such as waste incineration, power generation, iron making, chemicals, and petroleum. Or the cleaning method of the plant equipment provided with the pre-processing process which wets deposits, such as a clinker, and the removal process which removes the said deposits moistened from the said plant equipment is disclosed. Further, the removal step is removal by blasting a polishing material on the deposit, removal by a jet that sprays water on the deposit, removal by manual operation using a keren rod, a vibration tool, an impact tool, vacuum, or the like. At least one of them is used.

JP 2004-202485 A

However, the method shown in Patent Document 1 wets the deposit with water before removing the deposit adhering when it is burned in a refuse combustion furnace, and removes the deposit with reduced adhesion by wetting. It is also necessary to have a step of removing it even if it is moistened to reduce the adhesive force.
Since the operation is stopped at the time of regular inspection of plant equipment, it is desirable to start operation as soon as possible in order to make a profit, and it is necessary to remove the clinker as soon as possible to shorten the regular inspection period even one day. ing.

  Therefore, in view of the problems of the prior art, the present invention provides a furnace wall structure for plant equipment that can easily peel off deposits adhering to the inner wall surface of the plant equipment when operation is stopped during regular inspections. The task is to do.

In order to solve such a problem, in the furnace wall structure of the plant equipment formed by deposits such as ash, fly ash, clinker, etc. on the inner wall surface consisting of the metal wall of the plant equipment,
Coating the inner wall surface with a coating agent that chemically changes to a state where the inner wall surface comprising the metal wall of the plant equipment is peeled off from the boundary of the metal wall by wetting with water, and then coating with the coating agent The adhering matter adhering to the top is discharged, and the adhering matter is configured to be peelable from the inner wall surface of the plant equipment.

  According to this invention, the inner wall surface consisting of the metal wall of the plant equipment is preliminarily applied with a coating agent that chemically changes to a state where it can be peeled off from the boundary of the metal wall by wetting with water. Thus, the deposit can be peeled off from the inner wall surface of the plant equipment simply by discharging water to the deposit adhered to the coating film by the coating agent, and the deposit removal efficiency is increased. And since a deposit | attachment peels easily from the boundary of a metal wall, possibility that a deposit | attachment will fall naturally also increases.

Moreover, the coating agent applied to the inner wall surface of the plant equipment is a metal oxide, which changes to a hydroxide by reaction with water.
As described above, when a metal oxide is used as a coating agent, and the metal oxide is converted into a hydroxide by reaction with water, the coating agent applied to the furnace wall of the plant equipment is wetted with water. Since the volume change due to or the strength of the hydroxide itself is not strong, the adhesion strength is lowered, and the deposits are easily peeled off.

In addition, the coating agent is a powder solidified body formed by being sprayed on a metal wall in a state of being mixed with a vaporized liquid.
According to this invention, the coating agent which is a granular solidified body is sprayed on the inner wall surface which consists of a metal wall of plant equipment in the state mixed with the vaporization liquid which has volatility. Thereby, the said vaporization liquid vaporizes on the said inner wall surface, a coating agent adheres to the inner wall surface, and a film is formed. As described above, since the adhesion strength of the coating film is reduced by being wet with water as described above, the coating film can be easily peeled off even if the deposit is adhered.

Furthermore, the coating agent is characterized by containing calcium oxide or magnesium oxide powder. By using a coating agent containing calcium oxide or magnesium oxide powder as a coating agent at the site where deposits adhere and solidify, the coating film is thermally stable at high temperatures and reacts with water at low temperatures. It turns into a hydroxide. Therefore, the deposits can be easily peeled off by draining the deposits after stopping the operation of the plant equipment for regular inspection.
Note that both calcium oxide and magnesium oxide are inexpensive and are preferably used as the coating agent described above. Magnesium oxide in particular has good coatability and has better peelability since its adhesion strength is weaker than calcium oxide.

According to the present invention, the inner wall surface made of the metal wall of the plant equipment is preliminarily coated with a coating agent that chemically changes to a state where it can be peeled off from the boundary of the metal wall by wetting with water. Since the deposit can be easily peeled off from the inner wall surface of the plant equipment simply by discharging water to the deposit adhered to the coating film by the coating agent, the deposit removal efficiency is increased. And since a deposit | attachment peels easily from the boundary of a metal wall, possibility that a deposit | attachment will fall naturally also increases.
Therefore, it is possible to provide a furnace wall structure for plant equipment that is configured so that deposits attached to the inner wall surface of the plant equipment can be easily peeled off when the operation is stopped by regular inspection or the like.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.
Here, the furnace wall structure of the plant equipment in the embodiment of the present invention is applied to plant equipment such as power generation, waste incineration, iron making, chemical, petroleum, etc., and wall surfaces of boilers, main steam pipes, reheater pipes, piping, etc. In particular, it is formed at a site where deposits such as adhering ash, fly ash, or clinker adhering to adhering are adhered and solidified.

FIG. 1 is a cross-sectional configuration diagram of a spray gun according to an embodiment of the present invention.
A spray gun 3 shown in FIG. 1 applies an application agent, and a main body 12 and a container 4 are integrally formed, and a passage 10 through which compressed air is communicated is formed inside the main body 12 and an application. And an outlet 13 for spraying the agent.

The coating agent in this embodiment contains calcium oxide or magnesium oxide powder, and when applied to the furnace wall with the spray gun 3, a suspension mixed with a vaporized liquid is used. The coating agent is preferably calcium oxide or magnesium oxide because it is inexpensive, but strontium oxide or barium oxide can also be used. The vaporized liquid is preferably an alcohol having excellent volatility, and ethanol or propanol is particularly preferable from the viewpoints of volatility and handleability.
The particle size of the coating agent, the type of alcohol and the blending ratio, etc. are not limited as long as the concentration can be sprayed and can be applied to the site after spraying, but the powder in the suspension in which the coating agent and alcohol are mixed settles. In order to avoid this, the particle size is preferably 50 μm or less.

In FIG. 1, the suspension 4 of the coating agent and alcohol is supplied to the container 4, and the stirring blade 7 is rotated by the stirring motor 8 to stir the suspension 5 in the container 4 so that the powder as the coating agent does not settle. The
The suspension 5 to be agitated is adjusted by the compressed air introduced into the passage 10 from the air compressor 9 through the pipe 11 by adjusting the outflow amount from the container 4 by the valve body 6 provided between the container 4 and the main body 12. It is carried and sprayed from the outlet 13 toward the furnace wall. The sprayed portion is particularly preferably a portion where clinker is supposed to adhere, but may be sprayed on the entire furnace wall.

The sprayed coating agent vaporizes alcohol and is coated on the furnace wall as shown in FIG. FIG. 2 is a schematic cross-sectional view showing a coating state of the coating agent on the furnace wall and a clinker adhesion state.
As shown in FIG. 2, the coating agent applied to the furnace wall 1 forms a film 2. The coating 2 made of this coating agent is thermally stable at a high temperature. The thickness of the coating 2 is preferably about several tens of microns that does not peel at high temperatures.

When the coating 2 is formed on the furnace wall 1 and the plant equipment is operated, the clinker 15 is formed on the coating 2 as shown in FIG. The clinker 15 formed in this way can be easily separated from the boundary of the furnace wall 1 made of a metal wall by discharging water to a place where the clinker 15 is formed after stopping the operation of the plant equipment such as at the time of regular inspection. The coating 2 that chemically changes to a certain state can be easily peeled off.
The clinker that has become easy to peel off can be removed by natural fall, it can be removed by a soot blower, deslagger or water discharge, and it is removed from the furnace wall by applying impact or vibration using a tool. It is also possible.

  According to the present invention, when the operation is stopped at the time of regular inspection or the like, it can be configured so that the deposits attached to the inner wall surface of the plant equipment can be easily peeled off, so power generation, waste incineration, iron making, chemicals, petroleum This is useful when the plant equipment is applied to the furnace wall structure.

It is a section lineblock diagram of a spray gun in an embodiment of the present invention. It is a schematic sectional drawing which shows the application condition of the coating agent in a furnace wall, and the adhesion condition of a clinker. It is explanatory drawing which shows the condition of the clinker adhering to the furnace wall of the conventional coal burning boiler, and the method of removing the clinker.

Explanation of symbols

1 Furnace wall 2 Coating 3 Spray gun 4 Container 5 Emulsion 7 Stirring blade 15 Clinker

Claims (4)

In the furnace wall structure of plant equipment formed by deposits of ash, fly ash, clinker, etc. on the inner wall surface consisting of the metal wall of the plant equipment,
Coating the inner wall surface with a coating agent that chemically changes to a state where the inner wall surface comprising the metal wall of the plant equipment is peeled off from the boundary of the metal wall by wetting with water, and then coating with the coating agent A furnace wall structure for plant equipment, characterized in that water is discharged to the deposit attached on the top so that the deposit is peelable from the inner wall surface of the plant equipment.   The furnace wall structure for plant equipment according to claim 1, wherein the coating agent applied to the inner wall surface of the plant equipment is a metal oxide and changes into a hydroxide by reaction with water.   The furnace wall structure for plant equipment according to claim 2, wherein the coating agent is a powder solidified body formed by being sprayed on a metal wall in a state of being mixed with a vaporized liquid.   The furnace wall structure for plant equipment according to claim 3, wherein the coating agent contains calcium oxide or magnesium oxide powder.

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