JP2002059192A - Method of preventing adhesion of silicate-containing scale of heat exchanger and removing the scale - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system which is effectively preventing or suppressing the adhesion of scale containing silicate to the pipe wall surfaces of a heat exchanger even without using a chemical agent and is capable of effectively removing the scale once adhered to the pipe wall surfaces without requiring stopping of the heat exchanger. SOLUTION: This method of preventing the adhesion of the silicate-containing scale of the heat exchanger characterized in that tourmaline moldings consisting of many tourmaline particulates and inorganic insulators are disposed in the arbitrary positions on an upstream side of a water course for the primary cooling water (aqueous medium rising to a high temperature by coming into contact with a heat source) and/or secondary cooling water supplied to the heat exchanger and the method of removing the silicate-containing scale adhered to the inside of the heat exchanger.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for preventing silicate-containing scale from adhering to a heat exchanger and a method for removing silicate-containing scale adhering inside the heat exchanger.

[0002]

2. Description of the Related Art In many factories, particularly factories having equipment for performing processes such as mixing, reaction, and separation of substances (eg, chemical factories), heat generated in the course of manufacturing (chemical reaction) is generated. It is common practice to recover the absorbed high-temperature aqueous medium using a heat exchanger. There are various types of heat exchangers, and in each case, primary cooling water (cooling water that directly cools the heat source, which absorbs heat and becomes high temperature) or secondary cooling water passes inside It is composed of a thin pipe (tube) and a container that temporarily holds the secondary cooling water or primary cooling water supplied around the pipe.

[0003] In a general manufacturing plant, industrial water is usually used to absorb heat generated during the manufacturing process. Also,
Water used for the purpose of cooling the hot high-temperature industrial water or recovering the heat is also usually industrial water. Various metal components, inorganic substances, and organic substances are dissolved and dispersed in industrial water. Therefore, scales made of various substances are likely to adhere to the wall surface of the pipe inside the heat exchanger in which heat exchange between the primary cooling water (high-temperature water) and the secondary cooling water is performed. Above all, scales mainly composed of silicates (including silicon oxides) originating from silicon mixed in with industrial water due to contact with soil and rocks have low thermal conductivity, so their adhesion is heat exchange. The heat exchange function of the vessel is greatly reduced.

[0004] Also, once the scale mainly composed of silicate adheres to the wall surface of the pipe of the heat exchanger, it is difficult for the scale to be easily detached. It is necessary to temporarily stop the operation of the exchanger and perform a cleaning operation by a worker. However, when the operation of the heat exchanger is stopped, it is usually necessary to stop the entire production equipment to which the heat exchanger is attached, and the operation for cleaning the heat exchanger is stopped. Is a heavy burden on factory operation.

Heretofore, for the purpose of preventing the scale from adhering to the pipe wall surface of the heat exchanger or removing the scale once adhered, condensed phosphates, polyacrylic acid and salts thereof, quaternary ammonium salts, polycarboxylic acids, etc. Of various chemical agents have been developed. However, when chemical agents are added to an aqueous medium for a heat exchanger (primary cooling water or secondary cooling water), most of the aqueous medium is recycled and part of the aqueous medium is removed from the circulation system as wastewater. To be
There is a problem that the chemical agent needs to be added continuously or repeatedly, and the cost required for the addition is not small. In addition, in order to allow a part of the circulating water used for heat exchange to flow to the outside as wastewater, there is a problem that it is necessary to remove the added chemical agent.

[0006] Above all, the chemical agents that have been developed so far do not have a satisfactory effect of preventing scale adhesion or scale removal. In particular, when the temperature in summer is high, the adhesion of the scale on the pipe wall surface of the heat exchanger becomes remarkable, but a sufficient effect of preventing the adhesion of the scale cannot be obtained with the known chemical agents. It is said that washing with a strong acid such as hydrochloric acid or a strong alkali such as sodium carbonate is effective for removing scale once adhered.
The problem of wastewater treatment of washing water remains.

Without using a chemical agent, a magnetic field and an electromagnetic field generator are arranged around a channel for supplying water to a boiler or the like, and a magnetic field and an electromagnetic field are applied to water containing silicate ions passing through the channel. A method for preventing the generation of rust and / or scale in a water channel is disclosed in JP-A-2-227.
No. 193. However, according to the data reported in this publication, the occurrence of scale has been confirmed only inside the boiler. In addition, when employing this method, it is necessary to purchase an expensive magnetic field and electromagnetic field generator and attach it around the water channel, which is efficient when used at a factory site where a large amount of industrial water is required. I can't say that.

[0008] Japanese Patent Application Laid-Open No. 11-319886 also discloses that calcium carbonate, calcium silicate,
In order to prevent the adhesion of scales such as silica, ceramics obtained by crushing, molding and sintering natural stone containing alumina as a main component and containing oxides such as iron, magnesium, calcium, sodium and potassium A method is disclosed in which a sintered body is brought into contact with water supplied to a boiler. However, according to this publication, it is not clear which specific ceramic sintered body is effective, and no specific data indicating that the ceramic sintered body is effective for adhering scale is described.

Heretofore, techniques for purifying or activating water such as tap water using tourmaline (tourmaline) have been developed. It has long been known that tourmaline has a self-polarizing effect and is useful for purification treatment of tap water or the like by generating hydroxyl ions when placed in contact with water. However, in the state of the rough tourmaline, the purification action is not sufficient, so that the rough tourmaline is usually used in the form of fine particles by grinding. In addition, by separating each of the finely divided tourmaline particles with an insulating material, self-polarization is generated independently in each tourmaline particle, and water purification of the tourmaline particles per weight or volume is performed. Some measures have been taken to enhance the effect. As the improvement of such tourmaline fine particles for water treatment, the following inventions have been proposed so far.

Japanese Patent Publication No. 2710768 (Japanese Unexamined Patent Publication No.
Japanese Patent Application Publication No. 110468) discloses a molded product in which tourmaline fine particles are dispersed in a glass matrix and is suitable for water purification treatment. Tokuhei 7-3898
No. 7 discloses a tourmaline granule obtained by electrically insulating and solidifying between tourmaline fine powders and a water surface activation device using the same.

Japanese Patent Application Laid-Open No. H11-165167 discloses a porous tourmaline-containing molded article formed from an alumina powder and a tourmaline powder.

Japanese Patent Application Laid-Open No. Hei 9-157000 discloses that tourmaline fine powder, ceramic powder,
Then, tourmaline ceramics obtained by sintering a mixture of silver into pellets are disclosed.

Japanese Patent Application Laid-Open No. H11-89906 discloses a ceramic for a bathroom, in which hot spring component powder, tourmaline fine powder, glass powder and other binder powder are mixed and sintered to form a porous body.

Japanese Patent Application Laid-Open No. 10-17378 discloses a porous tourmaline molded product obtained by sintering a mixture of fine tourmaline powder and fine powder of polyethylene or polypropylene. Japanese Patent Application Laid-Open No. 11-322469 discloses a porous material obtained by kneading a tourmaline particle as a main raw material, a porous fine particle (zeolite) as an auxiliary raw material, an adhesive and a plastic raw material, and firing at a low temperature of about 800 ° C. A tourmaline ceramic material is disclosed.

Japanese Patent Application Laid-Open No. 11-192479 discloses an invention for improving the efficiency of water recycling by packing raw tourmaline or molded tourmaline into a column provided in a water supply system. Japanese Patent Application Laid-Open No. Hei 10-314752 discloses that a material such as raw stone of tourmaline or molded body of tourmaline powder, which generates hydroxyl ions upon contact with water, is contained in a porous container such as a wire net and has a bottom in a water storage tank. A system for standing still in water to prevent the decay of water and the generation of odor is disclosed.

The water purifying action of tourmaline described in the above-mentioned patent-related publication is not particularly limited, but is used for purifying water having a substantially high purity such as tap water. No specific study has been made on the purification effect of industrial water, which is far less clean.

[0017]

SUMMARY OF THE INVENTION The present invention can effectively prevent or suppress the adhesion of scale containing silicate to the pipe wall inside a heat exchanger without using a chemical agent. It is another object of the present invention to develop a scale adhesion prevention / removal system capable of effectively removing scale once attached to the pipe wall surface without having to stop the heat exchanger.

[0018]

According to the study of the present inventor, a tourmaline molded body formed by dispersing and binding tourmaline particles with an inorganic insulator is used to convert industrial water containing a large amount of a silicon component into a heat exchanger. When used as an aqueous medium (primary cooling water) or when such industrial water is used as secondary cooling water for a heat exchanger, any position upstream from the heat exchanger of the industrial water is used. When placed in constant contact with industrial water, scales containing silicate do not easily adhere to the pipe wall of the heat exchanger (inside or outside the pipe), and once on the pipe wall. It has been found that detachment of the scale containing the attached silicate can also be promoted.

Accordingly, the present invention provides a method of forming a plurality of tourmaline fine particles and an inorganic insulator at an arbitrary position upstream of a primary cooling water (high-temperature water) and / or secondary cooling water supplied to a heat exchanger. A method for preventing adhesion of a silicate-containing scale of a heat exchanger, comprising arranging a tourmaline molded body and making contact with water passing through the water channel or water stored in the water channel. The present invention also relates to a method in which a large number of tourmaline fine particles and an inorganic insulator are provided at an arbitrary position on the upstream side of a channel of primary cooling water and / or secondary cooling water supplied to a heat exchanger to which a silicate-containing scale is attached. There is also a method for removing a silicate-containing scale of a heat exchanger, which comprises arranging a tourmaline molded body and bringing the tourmaline molded body into contact with water passing through the water channel or water stored in the water channel.

In the method for preventing and removing scale from the heat exchanger according to the present invention, the tourmaline molded product is filled with a flexible bag-like container having an opening ratio of 50% or more (especially 70% or more) (preferably a flexible bag-like container). , And non-conductive), and it is preferable to arrange it suspended on the upstream side of the heat exchanger. However, if the primary cooling water and / or the secondary cooling water forms a circulating system, the heat exchanger is located on the upstream side at any position in the water channel of the circulating system. As a result, there is no limitation on the position where the molded body is arranged. However, in this case as well, it is preferable that the tourmaline molded body is accommodated in a bag-like container (preferably, flexible and non-conductive) and is suspended.

The bag-like container is preferably composed of a bag made of a non-conductive synthetic fiber net and a metal ring having a function of retaining the shape. Preferably, a suspension string is provided. And it is preferable that all of the side surface, the top surface, and the bottom surface of the bag-like container are in a net shape.

The tourmaline molded article used in the method for preventing or removing the silicate-containing scale of the heat exchanger according to the present invention is characterized in that a large number of tourmaline fine particles have inorganic insulating fine particles interposed between the tourmaline fine particles, It is desirable that the inorganic insulator fine particles are fixed to each other in a point-adhesion state in the presence of the inorganic adhesive component to be aggregated to form a spherical spherical body, which is a spherical spherical body.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION There is no particular limitation on the tourmaline molded product used in the method for preventing and removing the silicate-containing scale of the heat exchanger of the present invention.
Many tourmaline fine particles, many inorganic insulator fine particles,
Mixing an inorganic adhesive that melts within a temperature range of 600 to 950 ° C. in an amount of 1 to 10% of the total weight of the tourmaline fine particles and the inorganic insulating fine particles; Forming a lump while applying the organic adhesive aqueous solution;
By heating to about 950 ° C., the inorganic adhesive is melted or reacted while substantially maintaining the shapes of the tourmaline fine particles and the inorganic insulating fine particles, and then manufactured by utilizing a method including a step of cooling. The above-mentioned porous spherical tourmaline molded article is desirable.

Preferred embodiments of the above-mentioned tourmaline molded body are described below. (1) The average particle size ratio between the tourmaline fine particles and the inorganic insulating fine particles is in the range of 0.2 to 5 for the former and 1 for the latter. (2) The average particle size ratio of the tourmaline fine particles to the inorganic insulating fine particles is in the range of 0.5 to 2 for the former and 1 for the former. (3) The diameter of the tourmaline fine particles is in the range of 1 to 50 μm. (4) The diameter of the tourmaline fine particles is in the range of 3 to 30 μm.

(5) The weight ratio between the tourmaline fine particles and the inorganic insulating fine particles is in the range of 0.2 to 5 for the former and 1 for the latter. (6) The inorganic insulating fine particles are clayey fine particles. (7) The particle diameter of the inorganic insulating fine particles is in the range of 1 to 50 μm. (8) The particle diameter of the inorganic insulating fine particles is in the range of 3 to 30 μm. (9) An inorganic adhesive component is a vitreous material that melts in the range of 600 to 950 ° C., or a reaction product or decomposition product thereof. (10) The compressive strength of the tourmaline molded product is 15 kg or more (especially 20 kg or more, the average value of the compressive strength of each spherical tourmaline molded product). (11) The average diameter of the tourmaline spherical molded body is 2 to 15 m
m, preferably 4 to 15 mm, especially 4 to 10 mm.

FIG. 1 shows the above-mentioned spherical tourmaline lump 1
FIG. 2 shows a conceptual diagram of the internal structure of a 0. FIG. 1 shows a part of the internal structure of the spherical tourmaline molded body in an enlarged state. In FIG. 1, the circular portion 11 with hatching is
1 shows a cross section of tourmaline fine particles. A plurality of adjacent tourmaline fine particles 11 are spatially separated from each other by inorganic insulating fine particles 12. The tourmaline fine particles 11 and the inorganic insulating fine particles 12 are joined to each other by an inorganic adhesive component 13 such as a vitreous material fixed around the contact point or a close point. Therefore, the surface of the tourmaline fine particles 11 on which the inorganic adhesive component 13 is not disposed is exposed toward the pores. Accordingly, each of the tourmaline fine particles 11 self-polarizes inside thereof and reacts with water, water vapor, or the like in contact with the exposed surface to generate active ions such as hydroxyl ions.

There are no particular limitations on the tourmaline fine particles that can be used in the production of the above-mentioned spherical tourmaline molded body, as long as they are porous tourmaline molded bodies containing tourmaline fine particles and an inorganic insulator. That is, tourmaline fine particles which can be used for the production of the above-mentioned spherical tourmaline molded product by pulverizing a natural mineral known as tourmaline or tourmaline and performing a classification operation to adjust the particle size to an appropriate particle size if desired. Can be obtained. However, the fine particles of tourmaline used for producing the above-mentioned spherical tourmaline molded body preferably have a particle size (meaning an average particle size in the present specification) in the range of 1 to 50 μm, and more preferably in the range of 3 to 30 μm. It is particularly preferable that the thickness be in the range of 5 to 20 μm.

As the inorganic insulating fine particles, for example,
Inorganic insulator particles such as various clay particles, kaolin, alumina particles, titanium dioxide particles, and talc can be used. The inorganic insulator fine particles to be used do not melt in the firing step at the time of agglomeration after mixing with the tourmaline fine particles, and it is necessary to substantially maintain their own shape. However, its melting point (melting temperature) is generally 700 ° C. or higher, preferably 900 ° C. or higher, and particularly preferably 1000 ° C. or higher.

In order for the inorganic insulating fine particles to realize effective insulation between the adjacent tourmaline fine particles and to maintain the ratio of the exposed surface of the tourmaline fine particles at a suitable level, the particle size of the tourmaline fine particles is required. The ratio of the particle diameter of the inorganic insulating fine particles to the former is preferably in the range of 0.2 to 5 for the former 1, and more preferably in the range of 0.5 to 2 for the former 1. In particular, the former is preferably 0.8 to 1.2 with respect to the former 1.
Is preferably within the range. Therefore, the particle diameter of the inorganic insulator fine particles is preferably in the range of 1 to 50 μm, more preferably in the range of 3 to 30 μm, and particularly preferably in the range of 5 to 20 μm.

The inorganic insulating fine particles are preferably used in an amount of 0.2 to 5 parts by weight, more preferably 0.5 to 2 parts by weight, based on 1 part by weight of the tourmaline fine particles. Preferably, it is used in an amount in the range of 0.7 to 1.5 parts by weight.

In the production of the above-mentioned spherical tourmaline molded body, in order to realize strong bonding by point contact between the fine particles of tourmaline and the fine particles of the inorganic insulator, 600 to 500 parts are required.
It is preferable to use an inorganic adhesive such as a vitreous powder (eg, powdered silicate binder) that melts in a temperature range of 950 ° C. In addition, when a large amount of the inorganic adhesive is used, the amount attached to the surface of the tourmaline fine particles increases, and the exposed surface area of the tourmaline fine particles decreases.
1 of the total weight of tourmaline fine particles and inorganic insulator fine particles
It is preferable to use an amount in the range of 10% to 10% (particularly, 2% to 8%). And, for the tourmaline fine particles, the inorganic adhesive is 0.5 to 5% by weight (particularly, 1 to 4% by weight).
Is preferably used.

At the time of producing the above-mentioned spherical tourmaline molded body, first, a large number of tourmaline fine particles, a large number of inorganic insulating fine particles, and a particulate inorganic adhesive are mixed in a dry state, and then the tumbling molding is performed. Using a granulation device such as a granulation device (eg, a bread-type granulator), a spherical mass is formed while applying the aqueous organic adhesive solution to the resulting mixture, for example, in the form of a mist. In this granulation step, the inorganic adhesive particles are mainly localized around the junction or close point between the tourmaline fine particles and the inorganic insulating fine particles. If necessary, tourmaline fine particles, inorganic insulating fine particles, or inorganic adhesive particles may be replenished in the step of forming the massive compact.

The aqueous organic adhesive solution used in the above-mentioned mass production step is self-supporting, and is capable of maintaining the mass form until the inorganic adhesive is fixed by melting after the start of the subsequent firing step. Aqueous solution of an adhesive for molding, for example, CMC (carboxymethylcellulose)
And a 5 to 10% by weight aqueous solution. It is preferable that the massive compact has a spherical shape with an average diameter of 2 to 15 mm.

The bulk compact obtained in the above step is then placed in a heating furnace, and usually at a temperature of 600 to 950 ° C. (preferably 700 to 950) for about 3 to 15 hours.
° C), and then fired for about 30 minutes to 2 hours, while substantially maintaining the shape of the molded body of tourmaline fine particles and inorganic insulating fine particles, and mainly of tourmaline fine particles and inorganic insulating fine particles. The inorganic adhesive localized around the proximity point is melted or reacted. The calcined lump compact is then cooled in heating, taken out of the heating furnace, and cooled to room temperature to obtain a target spherical tourmaline compact (preferably having an average diameter of 2 to 15 mm).

In carrying out the method for preventing and / or removing the silicate-containing scale of the heat exchanger according to the present invention, a flexible non-conductive synthetic fiber net 21 as shown in FIG. A bag-shaped porous container formed from a metal ring 22 for maintaining the shape (a side, a bottom, and a top are both open, and the opening ratio is 50% or more, particularly 70%
%, And as shown in FIG. 3, the secondary cooling water is supplied to a heat exchanger 31 connected to a heat generating source 30 such as a chemical reaction device via a primary cooling water channel. Inside a reservoir (or water storage tank) 32 provided in a water channel connected by a water circulation system for supplying
It is preferable that the string is attached to the container and suspended in a bridge-like passage 33 bridged above the reservoir 32 so as to be suspended.

The heat exchanger is not particularly limited, but may be a tubular heat exchanger such as a coiled tube type, an open liquid film type, a double tube type or a multi-tube type, and a plate type, a jacket type or a spiral type plate. Type heat exchangers are commonly used. The pipe portion of the heat exchanger is usually made of iron, but may be made of another metal material such as stainless steel or copper.

As shown in FIG. 3, the bag-shaped porous container 23 filled with the tourmaline molded body is provided with a tank for storing industrial water or a flash tower (cooling) for circulating industrial water. In the interior of the tower 34, etc., likewise suspended inside them, or at the bottom,
It can also be placed in a state where it is kept from leaking. In particular, the tourmaline molded body container 23 disposed in a suspended state in a reservoir or a water storage tank, etc., sways due to movement of water and changes its position, so that contact between newly flowing water and the tourmaline molded body increases, Further, it is possible to effectively prevent solid contaminants such as sludge and algae, which are likely to be generated in ordinary industrial water, from adhering to and depositing on the tourmaline molded body surface.

In the case where solid contaminants such as sludge and algae accumulate on the surface of the tourmaline molded article in the tourmaline molded article container due to long-term use, a cleaning operation such as grasping the container string and rocking the container is performed. By doing
Solid contaminants can be easily removed.

[0039]

EXAMPLES Example 1 Production of Spherical Tourmaline Molded Article
Tourmaline fine powder (made in China, purity: about 100%, 325
50 parts by weight of mesh pass, average particle diameter: about 7 μm, 45 parts by weight of clay powder (dry powder of Frogome clay, 325 mesh pass, average particle diameter: about 7 μm), and sodium silicate powder (low-temperature sintered vitreous) Forming binder) 5 parts by weight,
This mixture was placed in a bread granulator and subjected to rotary granulation. At the time of this rotary granulation, carboxymethylcellulose (CM
C) Aqueous solution (Cellogen WSC (commercial product), concentration: about 7
%) Was appropriately sprayed on the granules to obtain granules.

Next, the obtained granulated product was placed in a heating furnace, heated to 700 ° C. over 8 hours, and then heated and fired at the same temperature for 1.5 hours. The mixture was allowed to cool for 8 hours. And take it out of the heating furnace,
A spherical tourmaline molded body was obtained. The resulting tourmaline molded body is agglomerated by a large number of tourmaline fine particles, the clay powder being interposed between the tourmaline fine particles, and the tourmaline fine particles and the clay powder being fixed to each other in a point contact state by vitreous material. And a porous spherical body (average particle size: 6 mm). In addition, the compressive strength of the obtained porous spherical body (compressive strength of one spherical body (measurement method: a porous spherical body is sandwiched between two steel plates) is pressed at a speed of 1 mm / min. (Measured weight when the body was broken) was about 35 kg.

[Example 2—Confirmation of Scale Removal Inside Scale of Heat Exchanger and Effect of Preventing Scale Adhesion by Tourmaline Molded Body] Secondary heat exchanger attached to a chemical reaction device of a chemical factory for removing reaction heat Although the cooling water was provided in the circulation system water channel, the ordinary polyphosphate-based scale inhibitor was added to the factory water, and a large amount of silicate was added to the pipe wall inside the heat exchanger of the circulation system. The circulatory system to which the contained scale was attached was evaluated.

The spherical tourmaline molded article produced in Example 1 was filled in a synthetic fiber net bag-like container having the structure shown in FIG. 2, and a water channel was formed in the heat exchanger 31 as shown in FIG. It was hung in a reservoir 32 connected via an intermediary, and was also moored at the bottom of the flash tower 34. And
Factory water was continuously passed through the pipe as before, and the operation of the heat exchanger was continued. After one month, the internal state of the heat exchanger was examined, and it was found that most of the silicate-containing scale had been removed.

After confirming the above condition, the continuous operation was further performed for one month. After the lapse of time, the condition inside the heat exchanger was examined. As a result, no increase in the attached amount of the silicate-containing scale was observed. Examination of the state of the spherical tourmaline molded article in the tourmaline molded article container revealed no destruction and little adhesion of solid contaminants such as sludge and algae to the surface of the tourmaline molded article.

[0044]

According to the present invention, a porous tourmaline molded article containing a large number of tourmaline fine particles and an inorganic insulator is provided.
In a heat exchange system using an aqueous medium as a heat exchange medium provided for removing or recovering heat generated in a chemical reaction device such as a chemical factory, high-temperature primary cooling water or the high-temperature primary cooling water is used. By contacting the cooled water or the secondary cooling water supplied to the heat exchanger, it is possible to efficiently remove the silicate-containing scale adhering to the inside of the heat exchanger. Even after the removal, new adhesion of scale can be effectively prevented.

[Brief description of the drawings]

FIG. 1 is a diagram schematically showing an internal structure of a spherical tourmaline molded body that is advantageously used in a method of preventing adhesion and / or removing a silicate-containing scale of a heat exchanger of the present invention.

FIG. 2 is a container of a spherical tourmaline molded article (flexible non-conductive synthetic fiber mesh) which is advantageously used in the method for preventing and / or removing the silicate-containing scale of the heat exchanger of the present invention. FIG. 2 is a perspective view (a spherical tourmaline molded body is housed) of a bag-like porous container composed of a metal ring and a metal ring.

FIG. 3 is a view of a container for accommodating the spherical tourmaline molded body of FIG. 2 arranged in a circulation system of industrial water for heat exchange circulated and supplied to a heat exchanger so that the tourmaline molded body is brought into contact with water. It is a schematic diagram which shows a state.

[Description of Signs] 10 Spherical tourmaline molded body 11 Tourmaline fine particles 12 Inorganic insulating fine particles 13 Inorganic adhesive component 21 Non-conductive synthetic fiber net 22 Metal ring 23 Flexible bag-like porous container 24 Container string 30 Heat generation Source 31 Heat exchanger 32 Reservoir for circulating water (secondary cooling water) 33 Bridge-like passage 34 Flash (cooling) tower

Claims (10)

[Claims] 1. The primary cooling water supplied to a heat exchanger and / or
Alternatively, a tourmaline molded body composed of a large number of tourmaline fine particles and an inorganic insulator is disposed at an arbitrary position on the upstream side of the water channel of the secondary cooling water, and water passing through the water channel or water stored in the water channel is disposed. A method for preventing silicate-containing scale from adhering to a heat exchanger. 2. A tourmaline molded body is accommodated in a flexible non-conductive bag-like container having an opening ratio of 50% or more, and the bag-like container is located on the upstream side of a primary cooling water and / or secondary cooling water channel. The method for preventing adhesion of a silicate-containing scale according to claim 1, wherein the method is arranged by suspending the silicate. 3. The bag-shaped container according to claim 2, wherein the bag-shaped container comprises a bag made of a non-conductive synthetic fiber net and a metal ring having a function of retaining the shape. Method for preventing adhesion of silicate-containing scale. 4. The bag-shaped container according to claim 2, wherein all of the side, top and bottom surfaces are net-shaped.
3. The method for preventing adhesion of a silicate-containing scale according to the above. 5. The tourmaline molded article is obtained by forming a large number of tourmaline fine particles with inorganic insulating fine particles interposed between the tourmaline fine particles, and forming the tourmaline fine particles and the inorganic insulating fine particles in a point-adhered state in the presence of the inorganic adhesive component. The silicate-containing scale according to any one of claims 1 to 4, wherein the silicate-containing scale is a spherical tourmaline lumps which are clumped together to form a porous sphere. How to prevent adhesion. 6. A method in which a number of tourmaline fine particles and an inorganic insulator are provided at an arbitrary position upstream of a primary cooling water and / or a secondary cooling water supplied to a heat exchanger to which a silicate-containing scale is attached. A method for removing a silicate-containing scale of a heat exchanger, comprising arranging a tourmaline molded body and contacting it with water passing through the water channel or water stored in the water channel. 7. A tourmaline molded body is accommodated in a flexible non-conductive bag-like container having an opening ratio of 50% or more, and the container is suspended upstream of a channel of primary cooling water and / or secondary cooling water. 7. The method for removing silicate-containing scale according to claim 6, wherein: 8. The bag-shaped container according to claim 7, wherein the bag-shaped container comprises a bag made of a non-conductive synthetic fiber net and a metal ring having a function of retaining the shape. Method for removing silicate-containing scale. 9. The bag-shaped container according to claim 7, wherein all of the side, top and bottom surfaces are net-shaped.
3. The method for removing a silicate-containing scale according to item 1. 10. The tourmaline molded article is obtained by forming a large number of tourmaline fine particles with inorganic insulating fine particles interposed between the tourmaline fine particles, and forming the tourmaline fine particles and the inorganic insulating fine particles in a point-adhered state in the presence of the inorganic adhesive component. The method for removing a silicate-containing scale according to any one of claims 6 to 9, wherein the spherical tourmaline mass is formed into a porous spherical body by being agglomerated by being fixed to each other.