JP2002048473A - Heating equipment using steam - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide heating equipment using steam that is capable of increasing the drying and firing speeds of an object by enhancing the heating efficiency of the object and manufacturing a product of stable quality and is economical with satisfactory working efficiency. SOLUTION: In heating equipment 10 that is provided in either one of the drying line of metal plates or wires, the drying line after painting and an oven or baking furnace in a color painting line and heat-treats the surface of an object 11 by exposing the surface of the object 11 to be heated to high- temperature gas, the high-temperature gas is heated to 200 to 900 deg.C, and the high-temperature gas comprises superheated steam containing 30 to 100 vol.% of moisture converted into a gas so as to enhance the heating efficiency of the object 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in a drying line for a metal plate or wire, a drying line after painting, a drying line for wood, paper, cloth, plastic, ceramics, or an oven or baking oven in a color painting line. The present invention relates to a heating facility using steam (for example, a drying facility, a baking facility, and a baking facility).

[0002]

2. Description of the Related Art Conventionally, a drying line for a metal plate or a wire rod,
Combustion gases (eg, those generated in factories) may be used as the heating medium for drying lines after painting, drying lines for wood, paper, cloth, plastic, and ceramics, or ovens or baking ovens for color painting lines. ) Or air heated by a heat exchanger and air heated by a heater. In general, drying is faster when using a gas that does not contain moisture than when using a gas that contains moisture.
Moreover, it is known that the dry state is also good. For this reason, the combustion gas (about 10 to 20 vol%) generated in the factory containing a large amount of water is rarely used for heating (drying or firing) the object while keeping the water-containing state. By using the combustion gas as a heat source to exchange heat with air, or by heating the air with another heat source and mixing the air with the combustion gas, the moisture in the combustion gas is reduced (moisture 5v).
ol% or less), the combustion gas is used. As described above, under the present circumstances, dry air with as little moisture as possible is produced, and this dry air is often used as a heat source for drying or firing (including baking) the surface of the object.

[0003]

However, when the surface of an object is heated using the above-mentioned combustion gas or dry air, there are the following problems. (1) Since the drying and baking speed of the object is low, the object cannot be processed in a short time, which is not economical. (2) Since it is not possible to recycle only the combustion gas and perform closed-circuit operation (circulation circuit) of the combustion gas, a large amount of heating heat of the combustion gas is required, which is not economical. (3) By using dry air, for example, the solvent contained in the color paint is volatilized, so that a large amount of heat is required to incinerate the volatilized solvent and the like, which is not economical. (4) The use of dry air may cause the surface of the object to be hardened, which may reduce the yield of products. (5) Exposing the object to dry air in the air may oxidize the object, which may result in a decrease in product yield. The present invention has been made in view of such circumstances, it is possible to increase the drying and firing rate of the object by increasing the heating efficiency of the object, and it is possible to produce a product of stable quality, An object of the present invention is to provide a heating facility using steam which is economical and has good working efficiency.

[0004]

According to the first aspect of the present invention, there is provided a heating apparatus using steam, which is a drying line for a metal plate or a wire, a drying line after coating, a color coating line oven or a baking furnace. By exposing the surface of the object to be heated to a high-temperature gas,
In the heating equipment for heating the surface of the object, the high-temperature gas is heated to 200 to 900 ° C., and the high-temperature gas is composed of superheated steam containing 30 to 100 vol% in terms of water, and the heating efficiency of the object Enhance. Note that the oven and the baking furnace are used for performing baking coating in which a color paint is firmly adhered to a steel plate or the like. As a result, the frequency of collision of the moisture contained in the high-temperature gas with the target object increases, and more components having wettability increase, so that the heating time of the target object can be reduced. Become. In addition, radiant heat (gas radiation) can be generated from the target object under the influence of moisture contained in the high-temperature gas. A heating facility using water vapor according to the second aspect of the present invention is provided in a drying line of any one of wood, paper, cloth, plastic, and ceramics, and exposes a surface of an object to be heated to a high-temperature gas. By that
In the heating equipment for heating the surface of the object, the high-temperature gas is heated to 200 to 900 ° C., and the high-temperature gas is composed of superheated steam containing 30 to 100 vol% in terms of water, and the heating efficiency of the object Enhance. This allows
The frequency of collision of the moisture contained in the high-temperature gas with the object increases, and the amount of wettable components increases, so that the heating time of the object can be reduced. In addition, radiant heat (gas radiation) can be generated from the target object under the influence of moisture contained in the high-temperature gas.

Here, in the heating equipment using steam according to the first and second aspects of the present invention, it is preferable that the water contained in the high-temperature gas is circulated. This makes it possible to reuse water without discharging it. Further, in the heating equipment using steam according to the first and second aspects of the present invention, it is preferable that the circulating system is provided with a removing means for removing foreign matter generated during drying. This makes it possible to remove foreign matter from the water contained in the high-temperature gas, so that it is possible to recover the solvent and the like generated from the target during drying, which has been incinerated until now.

That is, as described above, the point of the first and second aspects of the invention is that, when the object is heated (dried or fired), a certain temperature (reversal point temperature), contrary to the conventional concept. The above description is based on the fact that the higher the moisture content in the gas, the faster the drying rate and baking rate (higher drying efficiency and baking efficiency). Theoretically, the rate of temperature rise of the target object and the moisture and solvent in the target object becomes faster due to the increase in the thermal conductivity due to the increase in the amount of heat transferred and the increase in the momentum, and the use of the radiant heat by the gas radiation. Drying and baking (baking) time. The high-temperature gas containing water vapor has gas radiation, but there is almost no gas radiation even when the temperature of air containing no water vapor is high. This is because the amount of gas radiation increases as the amount of water vapor in the high-temperature gas increases.

[0007] In addition, by colliding a gas containing no oxygen (not zero but basically containing no oxygen) in the gas, such as superheated steam, the oxidation of the object can be reduced.
In other words, the first and second inventions are applied to a drying line for a metal plate or wire, a drying line after coating, a drying line for wood, paper, cloth, plastic, ceramics, or an oven or baking furnace for a color coating line. The heat medium of the heating equipment using the provided steam has a reversal point temperature (a temperature at which the evaporation rate of moisture is higher in superheated steam than in dry air, and the temperature is close to 200 ° C.). ,
The problem described above can be improved by using a high-temperature gas containing 30 to 100 vol% of water as gas.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the accompanying drawings to provide an understanding of the present invention. Here, FIG. 1 is a configuration diagram of a heating facility using steam according to the first embodiment of the present invention, and FIG. 2 is a configuration diagram of a heating facility using steam according to the second embodiment of the present invention. It is.

As shown in FIG. 1, a heating equipment 10 using steam according to a first embodiment of the present invention is provided with a drying apparatus arranged downstream of a production line (not shown) of a metal plate or wire rod. It is provided (installed) in one of a line (not shown), a drying line after painting (not shown), an oven (not shown) of a color painting line, and a baking furnace (not shown). The heating equipment 10 can be provided (installed) in any one of drying lines (not shown) of wood, paper, cloth, plastic, and ceramics. This heating equipment 10
Is the surface of the steel plate 11, which is an example of the object to be dried,
It has a function to heat-treat the surface of the steel plate 11 by exposing it to a high-humidity high-temperature gas. The heating equipment 10
The high temperature gas used for is heated to 200-900 ° C,
Moreover, this high-temperature gas converts moisture to gas,
It is made of superheated steam containing 30 to 100 vol% at the same pressure (for example, in a standard state), thereby increasing the heating efficiency of the steel sheet 11, that is, the drying efficiency or the firing (including baking) efficiency. The details will be described below.

The heating equipment 10 includes a steel sheet provided upstream of the heating equipment 10 for drying a steel sheet 11 manufactured in a predetermined shape (for example, a plate shape or a rectangular shape in plan view) on a manufacturing line. 11 to a carry-out port 13 of the steel plate 11 provided on the downstream side of the heating equipment 10.
A roller conveyor 15 having a plurality of rollers 14 is provided as an example of a transport unit capable of transporting the image. Inside the upper and lower inner walls 16 and 17 of the heating equipment 10, a steel plate 1
1 to allow the surface to be exposed to superheated steam,
A nozzle storage section 19 having a plurality of nozzles 18 for blowing out superheated steam (high-moisture gas) carried from a factory via a pipe (not shown) is provided vertically and in parallel along the roller conveyor 15. I have. Since the nozzle storage section 19 is divided into a plurality of sections (three sections in this embodiment) in the conveying direction of the roller conveyor 15, the temperature and the moisture of the superheated steam are adjusted for each nozzle storage section 19. Can be performed. Further, the plurality of rollers 14 provided on the roller conveyor 15 are made of a material that can withstand the temperature of the superheated steam filled in the heating equipment 10 and the use environment, for example, stainless steel.

[0011] Here, the water contained in the superheated steam is cooled by being used for drying the steel sheet 11 to become a liquid, and is turned into a gas by being heated by a heating device (not shown) or the like. Therefore, by installing a pipe (not shown) from a portion for collecting water cooled for use in drying the steel plate 11 to a portion for heating the collected water, and providing a system for circulating water, Water contained in the superheated steam can be recycled. At this time, in the system that circulates water,
It is preferable to provide a filter as an example of a removing unit for removing foreign substances (for example, gas and oil, etc.) generated during drying, a device for separating water and oil, and the like. Thereby, even when the collected water is used repeatedly, there is no possibility that foreign matter adheres to the surface of the steel plate 11.

Here, the reason why the temperature of the high-temperature gas and the moisture converted into the gas are limited to the above numerical ranges will be described. First, the lower limit value of the temperature was set to 200 ° C. in consideration of the fact that the steel sheet 11 can be efficiently dried in a state where the gas contains gasified water (steam). On the other hand, the reason why the upper limit value is set to 900 ° C. is because the economical efficiency of heat energy required for heating the gas, the saturated state of the effect of drying the steel sheet 11 and the like are taken into consideration. Note that comparing the case where the gas contains moisture and the case where the gas does not contain moisture, the heating temperature of the gas is 200
In the vicinity of ° C., no significant difference in drying effect is observed. Therefore, the temperature is preferably 250 to 700 ° C. in consideration of the temperature at which the gas can contain water, the drying efficiency can be improved as compared with the case where the gas does not contain moisture, and the economical efficiency, and the like. It is preferable that

[0013] The gaseous moisture is the gaseous steel 1
Considering that the surface of the steel plate 11 can be dried efficiently by colliding with the surface of the steel sheet 1, the water that can generate radiant heat from the target object under the influence of the water contained in the gas is used. Considering this, the lower limit was set to 30 vol%. On the other hand, the reason why the upper limit value is set to 100 vol% is that the effect of drying appears more largely due to an increase in gasified moisture. By using superheated steam as the high-temperature gas, it is possible to dry the steel sheet 11 in a shorter time. Here, in order to dry the steel sheet 11 more efficiently, the moisture of the high-temperature gas is
It is preferably 0 to 100 vol%, more preferably 50 to 100 vol%.

Next, a drying method for drying the steel sheet 11 using the heating equipment 10 using steam according to the first embodiment of the present invention will be described with reference to FIG.
First, the steel plate 11 manufactured on the manufacturing line and having a wet surface is stacked on the rollers 14 of the roller conveyor 15 of the heating equipment 10. Roller 14 of roller conveyor 15
The steel plate 11 loaded on the upper side is conveyed in the direction of the carry-out port 13 by driving the rollers 14 of the roller conveyor 15 by, for example, a motor (not shown). On the other hand, the inside of the heating equipment 10 is provided with a predetermined temperature (for example, 200 to 900)
° C), and predetermined moisture (for example, 30 to
100 vol%) adjusted high temperature gas is blown out,
Hot gas is full.

Therefore, the rollers 14 of the roller conveyor 15
The steel plate 11 loaded on the upper side is loaded into the entrance 12 of the heating equipment 10.
From the heating equipment 10 and exposed to a high-temperature gas filled inside the heating equipment 10 for a certain time (for example, about 1 to 100 minutes). Thereby, the frequency of collision of the moisture contained in the high-temperature gas with the steel sheet 11 and becoming gas increases, so that the drying time of the steel sheet 11 can be reduced. In addition, radiant heat (gas radiation) can be generated from the target object under the influence of moisture contained in the high-temperature gas.
Therefore, the steel sheet 11 can be economically dried without using a large amount of heat for drying the steel sheet 11. Then, the steel plate 11 dried inside the heating equipment 10 is carried out from the carry-out port 13 of the heating equipment 10.

Next, a heating apparatus 20 using steam according to a second embodiment of the present invention will be described with reference to FIG. 2. However, except for the changed parts, the heating apparatus 20 according to the first embodiment of the present invention will be described. Since it is the same as the heating equipment 10 using steam, the same members are denoted by the same reference numerals and detailed description thereof will be omitted. As shown in FIG. 2, the heating equipment 20 using steam according to the second embodiment of the present invention includes a drying line (not shown) disposed downstream of a metal plate or wire rod production line (not shown). No), a drying line after painting (not shown), an oven (not shown) in a color painting line, or a baking furnace (not shown). In addition, this heating equipment 20
Can be provided (installed) in a drying line (not shown) of any one of wood, paper, cloth, plastic, and ceramics. The heating equipment 20 includes steel plates 21, 22, 23, and 24, which are examples of an object to be dried.
(Since the materials of the steel plates are the same and only the shape is different,
A function of heating the surface of the steel sheet 21 by exposing the surface of the steel sheet 21 to a high-temperature gas (superheated steam) having a high moisture content is provided. In addition, this heating equipment 2
The high-temperature gas used at 0 is heated to 200 to 900 ° C., and the high-temperature gas converts moisture into a gas, and is 30 to 100 vol% at the same temperature and pressure (for example, in a standard state).
The heating efficiency of the steel plate 21, that is, the drying efficiency or the sintering (including baking) efficiency is increased.

The heating equipment 20 includes a steel plate provided upstream of the heating equipment 20 for drying a steel sheet 21 manufactured in a predetermined shape (for example, a plate shape or a rectangular shape in plan view) on a manufacturing line. 21 to a carry-out port 13 of a steel plate 21 provided downstream of the heating equipment 20.
Is provided with a net-type conveyor 26 having a net 25 (for example, a wire net or the like) as an example of a conveying means capable of conveying the sheet. The net-type conveyor 26 is provided with a plurality of rollers 27 that support and transport the net 25 to such an extent that the net 25 does not become loose even when the steel plate 21 is stacked on the net 25. The net 25 and the rollers 27 are made of a material that can withstand the temperature of the high-temperature gas filled inside the heating equipment 20 and the use environment, for example, stainless steel. Thereby, even if the object is a small object, if the object can be loaded on the net 25 of the net-type conveyor 26, the object can be conveyed on the net-type conveyor 26 without dropping the object from the net 25, It becomes possible to dry the surface of the object inside the heating equipment 20.

As described above, the present invention has been described with reference to the first and second embodiments. However, the present invention is not limited to the configuration described in the above embodiment, and claims And other embodiments and modifications that can be considered within the scope of the matters described in the range. For example,
In the first and second embodiments, the case where water is contained in the high-temperature gas has been described. However, other components capable of generating radiant heat from the object, for example, carbon dioxide (CO ₂ ) May be contained in the hot gas. As a result, more radiant heat can be generated from the target object. Therefore, the steel sheet can be economically dried without using a large amount of heat for drying the steel sheet.

Further, in the first and second embodiments, the temperature and moisture of the superheated steam blown out from the nozzles of the respective nozzle storage sections provided inside the upper and lower inner walls of the heating equipment are determined. The case where the temperature and the predetermined moisture are adjusted and the inside of the heating equipment is filled is shown. However, the temperature and moisture of the superheated steam are changed from the upstream side to the downstream side of the heating equipment, and each space is filled with the superheated steam adjusted to the predetermined temperature and the predetermined moisture to efficiently dry the steel sheet. It can also be done economically. Accordingly, the steel sheet can be more economically dried without using a large amount of heat for drying the steel sheet carried into the heating equipment.

In the first and second embodiments, a roller conveyor having a plurality of rollers and a net-type conveyor having a net are used as the means for transporting the steel sheet, respectively. The results are shown for the case where the drying was performed. However, depending on the size and shape of the steel plate to be dried, a steel plate is hung on a hanging member provided on the rail member by using a ceiling-mounted transfer device having a rail member, and the hanging member is moved. Thus, the surface of the steel sheet can be dried by exposing the surface of the steel sheet to superheated steam. In the first embodiment, the superheated steam is filled in the heating equipment to dry the surface of the steel sheet. However, it is also possible to spray superheated steam on the surface of the steel sheet if it is possible to dry the steel sheet whose surface is wet. Thereby, it is considered that the wettability of the superheated steam to the surface of the steel sheet is enhanced, and the surface of the steel sheet can be more efficiently dried. Further, in the first embodiment, the steel sheet is heated using a transfer means inside the heating equipment filled with the superheated steam adjusted to the predetermined temperature and the predetermined moisture by using the transfer means. The case where the surface of the steel sheet is dried by being exposed to steam for a certain time is shown. However, it is preferable to change the time for exposing the surface of the steel sheet to the superheated steam depending on the shape and thickness of the steel sheet, and this time can be adjusted by changing the transfer speed of the transfer means.

[0021]

According to the first aspect and the third aspect dependent thereon,
In the heating equipment using steam described in 4, the frequency of collision of the water contained in the high-temperature gas with the target is increased, and more components having wettability are increased. Heating time can be shortened.
In addition, it is possible to generate radiant heat from the target object under the influence of moisture contained in the high-temperature gas. As a result, it becomes possible to use the combustion gas without reducing the moisture that has become gas from the combustion gas as in the related art, thereby improving the workability. Also, with the generation of radiant heat,
Since the rise in the temperature of the surface layer of the object can be promoted, the object can be dried in a short time. Therefore, the object can be economically dried without using a large amount of heat for drying the object. In the heating equipment using water vapor according to claim 2 and subordinate claims 3 and 4, the frequency of collision of the water contained in the high-temperature gas with the object becomes high, and the object becomes wet. Since the number of components having properties increases, the heating time of the object can be reduced. Further, it becomes possible to generate radiant heat from the target object under the influence of moisture contained in the high-temperature gas. Thereby, the rise of the temperature of the surface layer of the object can be promoted with the generation of the radiant heat, so that the object can be dried in a short time. Therefore, the object can be economically dried without using a large amount of heat for drying the object.

In particular, in the heating equipment using steam according to the third aspect, it is possible to reuse water without discharging water. Therefore, it becomes possible to include water in the hot gas without replenishing a large amount of water,
The economy is good. In the heating equipment using steam according to the fourth aspect, it is possible to remove foreign substances from the water contained in the gas, so that it is possible to recover the solvent and the like generated from the object during drying, which has been incinerated until now. Becomes Therefore, the amount of heat required for incineration is not required, and the recovered solvent and the like can be reused, so that economy is improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a heating facility using steam according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a heating facility using steam according to a second embodiment of the present invention.

[Explanation of symbols]

10: heating equipment, 11: steel plate (object), 12: carry-in, 13: carry-out, 14: roller, 15: roller conveyor (conveying means), 16: upper inner wall, 17: lower inner wall, 1
8: Nozzle, 19: Nozzle storage unit, 20: Heating equipment, 2
1 to 24: steel plate (object), 25: net, 26: net type conveyor (conveying means), 27: roller

Claims (4)

[Claims] 1. A method for exposing a surface of an object to be heated, which is provided in one of a drying line for a metal plate or a wire, a drying line after coating, an oven or a baking furnace for a color coating line, to a hot gas. In the heating equipment for heating the surface of the object, the high-temperature gas is 200 to 90.
A heating equipment using steam, wherein the heating equipment is heated to 0 ° C., and the high-temperature gas is composed of superheated steam containing water in an amount of 30 to 100 vol% in terms of gas, thereby improving the heating efficiency of the object. 2. A heating device provided in a drying line of any one of wood, paper, cloth, plastic and ceramics, wherein the surface of the object to be heated is exposed to a high-temperature gas to heat-treat the surface of the object. In the equipment, the hot gas is 2
Heating using steam, wherein the high-temperature gas is composed of superheated steam containing water in an amount of 30 to 100 vol% in terms of gas, and the heating efficiency of the object is enhanced. Facility. 3. The heating equipment using steam according to claim 1, wherein the water contained in the high-temperature gas is circulated. 4. The heating equipment using steam according to claim 3, wherein the circulating system is provided with a removing means for removing foreign matter generated during drying.