KR20190129277A - Apparatus for recovering heat of melthing slag - Google Patents

Abstract

According to the present invention, a device for recovering a sensible heat of a molten slag comprises: a high pressure sealed container in which saturated water is accommodated, a steam pipe through which saturated steam is discharged is formed, and an internal pressure greater than an atmospheric pressure is maintained; a slag pressure injection unit for pressurizing and injecting the molten slag so as to block an outflow of an internal pressure of the high pressure sealed container when the hot molten slag is injected into the high pressure sealed container; and a slag crushing unit for crushing the molten slag with high pressure water so as to assemble the molten slag before the molten slag is inserted into the saturated water in the high pressure sealed container. The saturated steam of 100°C or more from the saturated water is generated by the sensible heat of the molten slag.

Description

Melt slag sensible heat recovery device {APPARATUS FOR RECOVERING HEAT OF MELTHING SLAG}

The present invention relates to a molten slag sensible heat recovery device, and a molten slag sensible heat recovery device for recovering the sensible heat of the molten slag.

Various types of waste heat are generated in the metal smelting process, including the steelmaking process, and the energy cost can be reduced by recovering and reusing the energy.

In particular, in recent years, the recovery and reuse of waste heat has been attracting attention as the most feasible way to reduce CO2 emissions.

The molten slag is discharged together with molten metal in the process of smelting ore, or in the process of smelting the metal. In the steelmaking process, blast furnace slag and converter slag are generated as molten slag.

Since the molten slag exists together with the molten metal, its temperature is high and therefore the amount of heat retained is also very high.

The molten blast furnace slag and the molten converter slag have a temperature of 1500 DEG C and a heat retention amount of more than 300,000 kcal per ton.

In order to recover the slag sensible heat (holding heat), the development of technology for various devices and methods have been attempted.A technique for slag sensible heat recovery is a slag assembly and heat recovery method using a windbreak method, a rotating disk, and slag into water. The water chain cooling method of cooling is mentioned as a typical thing.

The slag granulation and heat recovery method using the air crushing method and the rotating disk is a method in which molten slag is first assembled using air or a rotating disk, and then the slag particles are cooled using air to recover heat. It can raise the temperature above 500 ℃, it can increase the utilization value for the heat of recovery, such as producing high pressure steam.

However, first, the process of assembling molten slag is required, and the slag heat must be transferred to the air by using a heat recovery device, and finally, a complicated process of producing steam using the heat transferred to the air is required. There are limitations.

Furthermore, the molten slag has a high temperature and high adhesiveness, which makes it difficult to handle. As a result of the complicated steps described above, the molten slag is a major problem not only in generating heat loss but also in securing mechanical reliability. come.

In addition, molten iron, molten iron, slag in the semi-solid state, etc. are mixed in the contents of the molten slag according to the operating conditions of the generating equipment, in this case, various mechanical problems are caused during the urea process.

On the other hand, since the granulated high-temperature slag particles are cooled using air, there has been a fundamental problem that does not satisfy the cooling rate required to reuse the particle slag as a resource such as cement raw material.

Water-cooled water chain cooling is a method currently used as a cooling process for using molten slag as a cement raw material. In this method, since the cooling medium is water, it is possible to secure a sufficient cooling rate, thereby making it easy to secure the quality of slag resources.

However, such water chain cooling has the limitation that theoretically no water or steam above 100 ° C. can be obtained because all are under atmospheric pressure.

In recovering the sensible heat of slag, the temperature of the recovery medium such as water is very important in terms of securing the use of the recovery heat and the utilization of the recovery heat.

Even when electric power is produced using recovered heat, the efficiency is lowered at low temperatures, so that the actual power generation system is difficult to construct.

As a result, the molten slag heat recovery method using air can recover heat at a high temperature, but the process for realizing it is complicated, and not only does it cause mechanical problems, but it is also difficult to secure the required cooling rate. The method has been pointed out that the slag cooling rate can be secured but the utilization value is low because the temperature of the recovered energy is low.

Japanese Unexamined Patent Publication No. 193-311214

The present invention was made to solve the above problems, and an object thereof is to provide a molten slag sensible heat recovery apparatus capable of generating saturated steam of 100 ° C. or more by sensible heat of molten slag.

Melting slag sensible heat recovery apparatus according to an embodiment of the present invention to achieve the above object, the high-pressure airtight container is a saturated water accommodating, the steam pipe is discharged to the saturated steam is formed, the internal pressure is maintained above atmospheric pressure; A slag pressurizing injection unit which pressurizes and injects the molten slag so as to block the outflow of the internal pressure of the high pressure sealed container when the hot melt slag is injected into the high pressure sealed container; And a slag crushing unit for crushing the molten slag with high pressure water to granulate the molten slag before the molten slag is introduced into the saturated water in the high-pressure sealed container, from the saturated water by the sensible heat of the molten slag. The saturated steam is generated at 100 ° C. or higher.

Here, the slag pressure injection unit, may be installed in the slag inlet formed on one side of the high pressure sealed container, a screw feeder for injecting the molten slag into the high pressure sealed container while rotating.

In addition, the slag crushing unit, the slag bed disposed above the saturated water in the high pressure sealed container so as to pass through the molten slag injected by the slag pressure injection unit to the saturated water side; And a high pressure water line connected to the high pressure water pump outside the high pressure sealed container and extending into the high pressure sealed container to inject the high pressure water to the molten slag on the slag support.

In addition, a condenser is installed in the steam pipe, and the condenser is heat-exchanged with the saturated steam to make a high temperature water of 100 ° C. or more, and the hot water pipe passes through the saturated steam of the saturated water of the high pressure sealed container. A condensate tube connected to the high pressure water line may be formed to be recycled.

In addition, to control the pressure in the high pressure sealed container to cope with the pressure increase due to the boiling phenomenon generated in the high pressure sealed container, to remove the non-condensable gas generated in the high pressure sealed container, the high pressure sealed container Safety pipes fitted with safety valves may be installed.

Further, a slurry discharge pipe equipped with a slurry pump may be installed at the lower portion of the high pressure sealed container so as to discharge the slurry including the crushed slag crushed by the slag crushing unit and precipitated in the saturated water.

The molten slag sensible heat recovery apparatus according to the present invention has a stable and rigid sealed structure in which the high pressure is maintained to satisfy the high pressure condition larger than atmospheric pressure, thereby raising the temperature of the saturated water by raising the saturation pressure, The sensible heat has the effect of generating saturated steam of 100 ° C or more.

In addition, the present invention is composed of a slag pressure injection unit for injecting the molten slag into the high pressure sealed container while pressurizing the molten slag, so that the internal pressure of the high pressure sealed container does not drop when injecting the molten slag into the high pressure sealed container, and further the high temperature molten slag It has the advantage of injecting smoothly and continuously.

In addition, the present invention is composed of a slag crushing unit for assembling a high-temperature, high-adhesion molten slag using high pressure water, so that the production of process steam together with the granulation of molten slag is easily implemented without a complicated step. Accordingly, it is possible to secure mechanical reliability while suppressing heat loss as much as possible, and have an advantage of securing a fast cooling rate required to recycle crushed slag (particle slag) into a resource such as cement raw material.

1 is a view schematically showing a molten slag sensible heat recovery apparatus according to the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail. In the reference numerals to the components of each drawing, it is noted that the same reference numerals are assigned to the same components as much as possible even though they are displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

1 is a view schematically showing a molten slag sensible heat recovery apparatus according to the present invention.

Referring to the drawings, the molten slag sensible heat recovery apparatus according to the present invention includes a high pressure sealed container 100, the slag pressure injection unit 200, and the slag crushing unit 300.

Here, the high pressure airtight container 100 has a structure in which saturated water 21 is accommodated, a steam pipe 101 through which saturated steam is discharged is formed, and an internal pressure of atmospheric pressure or higher is maintained. At this time, the internal pressure of the high-pressure airtight container 100 is formed by the slag pressurization injection unit 200 to be described later by the hot molten slag continuously to be formed above atmospheric pressure, that is, high pressure, and further separate high-pressure forming member ( It may be formed by a high pressure).

That is, the high-pressure airtight container 100 has a sealed structure that can satisfy a high pressure condition larger than the atmospheric pressure so that the pressure above the atmospheric pressure can be maintained to generate saturated steam of 100 ° C. or higher therein.

Specifically, the high pressure airtight container 100 is formed to maintain the saturation pressure corresponding to the temperature of the saturated water 21 in which the internal pressure is integrated in the lower portion, the higher the temperature of the saturated water 21, the value of use of the recovery heat. As it is high, it has a stable and solid sealing structure in which high pressure can be maintained so that a high pressure condition larger than atmospheric pressure is satisfied to increase the temperature of the saturated water 21.

At this time, the high pressure airtight container 100, even if the slag pressure injection unit 200, the high pressure water line 320, and the slurry discharge pipe 700, which will be described later, including the steam pipe 101 is formed, the interior of the high pressure conditions described above It has a solid and stable sealing structure that can be achieved, and the specific shape structure is not limited by the present invention.

For reference, when the recovered thermal energy is generally used as a general process steam required in the factory, the temperature of the saturated water 21 or the saturated steam should be about 190 ° C. In this case, the pressure inside the high pressure sealed container 100 is used. Should be maintained at a saturation pressure of 12.8 atm (absolute pressure). At this time, in the present invention, the temperature of the saturated water 21 is at least 100 ° C or more, and the upper limit is not limited.

The slag pressurized injection unit 200 pressurizes the molten slag 11 to block the internal pressure leakage of the high pressure sealed container 100 when the molten slag 11 of the high pressure is injected into the high pressure sealed container 100. Configured to inject.

When the slag pressure injection unit 200 injects the molten slag 11 into the high pressure sealed container 100, the high pressure sealed container pressurizes the molten slag 11 so that the internal pressure of the high pressure sealed container 100 does not fall. It is preferable to take a structure that can be injected into the 100, and further smoothly and continuously inject the hot molten slag (11).

As an example, the slag pressure injection unit 200 may be provided with a screw feeder (210).

The screw feeder 210 is installed in the slag inlet (100a) formed on one side of the high pressure sealed container 100, and injects the molten slag 11 into the high pressure sealed container 100 while rotating.

That is, the screw feeder 210 is axially rotated and melted in the state where the molten slag 11 is filled in the screw groove formed in the screw shape while maintaining the structure of blocking the slag inlet 100a formed in the high pressure airtight container 100. The slag 11 is pushed into the high pressure airtight container 100.

Of course, at this time, the screw shape of the screw feeder 210 has a structure in which the number of screw rotations is as high as possible, even if the amount of the molten slag 11 injected into the high pressure sealed container 100 is reduced, the high pressure sealed container 100 It is desirable to have a structure that prevents the internal pressure of the maximal decrease.

As such, the slag pressurized injection unit 200 allows the molten slag 11 to be cooled in a state in which the molten slag 11 is pressurized to a pressure higher than atmospheric pressure inside the high pressure sealed container 100, thereby increasing the temperature of a recovery medium such as water vapor. It can be made higher than 100 ℃.

That is, the slag pressurized injection unit 200 to maintain the inside of the high-pressure sealed container 100 above atmospheric pressure, so as to generate saturated steam of 100 ° C or more from saturated water 21 by the sensible heat of the molten slag 11. can do.

Meanwhile, the slag crushing unit 300 is crushed with the high pressure water 22 to assemble the molten slag 11 before the molten slag 11 is introduced into the saturated water 21 in the high pressure sealed container 100. Is configured to.

In detail, the slag crushing unit 300 may include a slag support 310 and a high pressure water line 320.

Here, the slag support 310 is a saturated water 21 in the high pressure airtight container 100 so that the molten slag 11 injected by the slag pressure injection unit 200 passes while falling toward the saturated water 21 side. ) Is placed on the upper side.

In addition, the high pressure water line 320 is connected to the high pressure water pump 330 outside the high pressure sealing vessel 100 and extends into the high pressure sealing vessel 100 to the molten slag 11 on the slag support 310. High pressure water 22 is injected.

In this way, the slag crushing unit 300 is a high temperature and sticky molten slag 11 is granulated by using the high-pressure water 22, the process steam used in the factory together with the granulation of the molten slag 11 Since the generation of is simply implemented without complex steps, it is possible to ensure mechanical reliability while minimizing heat loss.

Furthermore, the slag crushing unit 300 can secure a fast cooling rate required to recycle the crushed slag 12 (particle slag) to resources such as cement raw materials.

On the other hand, in the present invention, the condenser 400 is installed in the steam pipe 101 of the high pressure airtight container 100.

The condenser 400 is heat-exchanged with saturated steam to penetrate the hot water pipe 500 to make hot water of 100 ° C. or higher, and recycle the saturated water liquefied into saturated water 21 of the high pressure airtight container 100. The condensate pipe 410 connected to the high pressure water line 320 may be formed.

In addition, the present invention may be installed a safety tube 600, the safety valve 610 is mounted on the high-pressure airtight container (100).

The safety tube 600 serves to control the pressure in the high pressure airtight container 100 to cope with the pressure increase due to the boiling phenomenon generated in the high pressure airtight container 100, and the high pressure airtight container 100. Removes non-condensable gases from water vapor.

Furthermore, in the present invention, a slurry discharge pipe 700 equipped with a slurry pump 710 may be installed at a lower portion of the high pressure airtight container 100.

The slurry discharge pipe 700 may be a slurry discharge pipe 700 equipped with a slurry pump 710 in the lower portion of the high pressure airtight container 100 to discharge the slurry (13).

At this time, the slurry 13 is crushed by the slag crushing unit 300 as a suspension includes crushed slag 12 precipitated in the saturated water (21).

As such, the crushed slurry 13 included in the slurry 13 discharged through the slurry discharge pipe 700 may be recycled into resources such as cement raw materials.

As a result, the molten slag sensitized heat recovery apparatus according to the present invention has a stable and rigid sealed structure in which the high pressure is maintained such that the inside of the molten slag is maintained at a pressure higher than atmospheric pressure, thereby raising the saturation pressure to raise the temperature of the saturated water 21. As a result, saturated steam of the molten slag 11 can generate saturated steam of 100 ° C or more.

In addition, the present invention is composed of a slag pressure injection unit 200 for injecting the molten slag 11 into the high pressure sealed container 100 while pressing the molten slag 11, the high pressure sealed when the molten slag 11 is injected into the high pressure sealed container 100 The internal pressure of the container 100 does not fall, and the hot molten slag 11 may be smoothly and continuously injected.

In addition, the present invention is composed of a slag crushing unit 300 for granulating the high-temperature and high-adhesion molten slag 11 using the high-pressure water 22, the process steam together with the granulation of the molten slag 11 Since the formation of is simply implemented without complicated steps, it is possible to secure mechanical reliability while suppressing heat loss as much as possible, and to recycle the crushed slag 12 (particle slag) into resources such as cement raw materials. Fast cooling speed can be achieved.

As described above, although the present invention has been described by way of limited embodiments and drawings, the present invention is not limited thereto and is intended by those skilled in the art to which the present invention pertains. Of course, various modifications and variations are possible within the scope of equivalents of the claims to be described.

11: molten slag 12: crushed slag
13: slurry
21: saturated water 22: high pressure water
100: high pressure airtight container 100a: slag inlet
101: steam pipe 200: slag pressure injection unit
210: screw feeder 300: slag crushing unit
310: slag support 320: high pressure water line
330: high pressure water pump 400: condenser
410: condensate water pipe 500: high temperature water pipe
600: safety tube 610: safety valve
700: slurry discharge pipe 710: slurry pump

Claims (6)

A high pressure hermetically sealed container in which saturated water is accommodated and a steam pipe through which saturated steam is discharged is formed, and an internal pressure of atmospheric pressure or higher is maintained;
A slag pressurizing injection unit for pressurizing and injecting the molten slag so as to block the outflow of the internal pressure of the high pressure sealed container when the hot melt slag is injected into the high pressure sealed container; And
And a slag crushing unit for crushing the molten slag with high pressure water to assemble the molten slag before the molten slag is introduced into the saturated water in the high pressure sealed container.
Melting slag sensible heat recovery device for generating the saturated steam of 100 ℃ or more from the saturated water by the sensible heat of the molten slag.
The method of claim 1,
The slag pressure injection unit,
A screw feeder installed at a slag inlet formed at one side of the high pressure airtight container and injecting the molten slag into the high pressure airtight container while rotating;
Melting slag sensible heat recovery device having a.
The method of claim 1,
The slag crushing unit,
A slag support disposed above the saturated water in the high pressure sealed container such that the molten slag injected by the slag pressurization injection unit falls while falling toward the saturated water side; And
A high pressure water line connected to a high pressure water pump outside the high pressure sealing container and extending into the high pressure sealing container to spray high pressure water onto the molten slag on the slag support;
Melting slag sensible heat recovery device characterized in that it comprises a.
The method of claim 3,
The steam pipe is installed with a condenser,
The condenser,
The hot water pipe is penetrated to exchange heat with the saturated steam to make hot water of 100 ° C. or more, and the condensed water pipe is connected to the high pressure water line to recycle the saturated water into the saturated water of the high pressure sealed container. Melt slag sensible heat recovery device.
The method of claim 1,
A safety valve is provided in the high pressure airtight container to control the pressure in the high pressure airtight container and to remove the non-condensable gas generated in the high pressure airtight container in order to cope with a pressure increase due to the boiling phenomenon generated in the high pressure airtight container. Melting slag sensible heat recovery device characterized in that the safety pipe is installed.
The method of claim 1,
Melt slag sensible heat recovery device characterized in that the slurry discharge pipe equipped with a slurry pump is installed in the lower portion of the high pressure sealed container to discharge the slurry containing the crushed slag crushed by the slag crushing unit precipitated in the saturated water.

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