JPS5934418B2 - Granulation and heat recovery equipment for metallurgical slag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a granulation and heat recovery apparatus for metallurgical slag generated in an ore refining process.

Conventionally, the metallurgical slag produced during the ore refining process is granulated using a granulation device called the slag method, and is effectively used for construction materials, etc. However, in terms of heat recovery from the metallurgical slag, It is in a state of no action. In other words, the metallurgical slag produced during the ore refining process is high in temperature and in large quantities, and the thermal energy carried away is enormous, but the reality is that all of it is wasted.

By the way, according to calculations, the amount of heat that metallurgical slag has is 12
If the temperature between 00℃ and 80℃ is about 300KcaVk, and the amount of metallurgical slag discharged from one blast furnace is 3000 tons/day, then 300×3000×103■9×108Kcal/
It becomes a day.

This shows how much heat is wasted. For the above reasons, various studies have been conducted regarding heat recovery.

One idea is to spray water onto the metallurgical molten slag to granulate it and at the same time recover the heat as steam, but there is a problem in that it is extremely difficult to extract the generated steam. This invention granulates metallurgical slag and at the same time
The purpose is to effectively recover the retained heat as steam. An embodiment of the present invention will be described below based on the drawings.

In FIG. 1, 1 is a furnace body, and one longitudinal end of the furnace body 1 has an input port 2 for metallurgical molten slag, and the other end has a discharge port 3.
are provided for each. Reference numeral 4 denotes a vibrating conveyor disposed directly below the input port 2, and between the vibrating conveyor 4 and the discharge port 3, five stirring blades 5 for metallurgical molten slag are disposed in front and rear stages in multiple stages.

Reference numeral 6 denotes a water-steam conversion passage that snakes through the upper part of the furnace body 1, and both ends of the passage 6 are connected to a load 9 such as a steam turbine via circulation piping T and 8. Piping 7
A pump 10 and a heat exchanger 11 are interposed therein.

Reference numeral 12 denotes a cold air-hot air conversion tower body connected to the outlet 3 of the furnace body 1, and both upper and lower ends of the tower body 12 are connected to circulation piping 1.
It is connected to the heat exchanger 11 via pipes 3 and 14, and a proar 15 is interposed in one of the pipes 13.

Reference numeral 16 denotes a metallurgical molten slag discharge port provided at the center of the lower part of the cold air/hot air conversion tower body 12, and around the discharge port 16, a plurality of branch pipes 17 are connected to the pipe 13 on the proar 15 side. is connected.

18 is a conveyor placed directly below the discharge port 16.

Further, in FIG. 2, reference numeral 19 indicates a driving device connected to one end of the rotating shaft 20 of each stirring blade 5. , 21 is a water supply pipe provided between the other ends of each rotating shaft 20 via a rotary joint 22,
During operation, water A is sequentially passed into the inside of each stirring blade 5 to cool it.

In the above configuration, the metallurgical slag is introduced onto the vibrating conveyor 4 from the inlet 2 of the furnace body 1, and is transferred to the stirring blade 5 side by the inclination and vibration of the vibrating conveyor 4.

Is each stirring blade 5 a driving device? At 19, the conveyor is driven in the direction of arrow B in FIG. 1 to sequentially transport the metallurgical molten slag from the vibrating conveyor 4 toward the discharge port 3 while stirring it. The water sent to the water-to-steam conversion passage 6 by the pump 10 absorbs the radiant heat of the metallurgical slag passing through the furnace body 1, increases its temperature, and becomes high-temperature steam.

This steam is supplied to a load 9 through a pipe 8, where it consumes thermal energy, condenses again, and is circulated through a pipe 7 to a water-steam conversion passage 6. The metallurgical slag transferred through the furnace body 1 is in a complete liquid phase when it is introduced from the inlet 2, but as it is stirred as described above, its radiant heat is removed, resulting in a final liquid phase. The particles are granulated and transported out of the furnace body 1 from the discharge port 3, that is, introduced into the cold air to hot air conversion tower body 12. The metallurgical molten slag introduced into the tower body 12 for converting cold air to hot air falls through the discharge port 16 onto the conveyor 18, and is conveyed by the conveyor 18 to a predetermined location.

The proa 15 connects each branch pipe 17 to a tower body 1 for converting cold air to hot air.
Air is blown into the tower body 12, and the metallurgical molten slag falling in the tower body 12 is further cooled by cold air flowing in a counterflow. Is the above cold air metallurgical? It absorbs the sensible heat of the slag and becomes hot air.

The water then flows to the heat exchanger 11, heats the piping 7, preheats the water flowing into the water-steam conversion passage 6, promotes the heat recovery effect as steam, and passes through the piping 13 to the proa 15. It is circulated. metallurgy? The temperature of the molten slag is about 1250°C when it is introduced into the furnace body 1, and from about 1200'C to 1200°C in the stirring zone.
000℃, and the tower body 1 for converting cold air to hot air
2, the temperature drops to about 80°C. When the temperature of the metallurgical slag is 900° C. or lower, the radiant heat absorption effect decreases. Therefore, the inflow water is finally preheated by blowing air as described above, but in that case, the metallurgical slag is thrown into the cold air-hot air conversion tower body 12 as granules,
Highly efficient preheating is expected due to the large heat dissipation surface area that comes into contact with the cold air. The metallurgical slag has a considerable adhesive force at around 1250°C, but since it is thrown onto the vibrating conveyor 4 at around 1250°C, it is quickly transferred to the stirring zone.

As mentioned above, according to this invention, metallurgy? While granulating the slag, the retained heat can be effectively recovered as steam.

Moreover, since the metallurgical molten slag is agitated as a means of granulation, the surface of the molten slag is constantly exposed to high temperatures. Heat recovery rate is high. Moreover, since the metallurgical slag is granulated by stirring from the liquid phase, it can be granulated with relatively small power. Furthermore, since the water-steam conversion passage is heated by radiation heat transfer, there is no difficulty in extracting the steam.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line A--A in FIG. 1. 1... Furnace body, 2... Inlet, 3... Outlet, 4...
... Vibration conveyor, 5... Stirring blade, 6... Water-steam conversion passage 9... Load, 10... Pump, 11...
・Heat exchanger, 12... Tower body for converting cold air to hot air, 15.
...Proa.

Claims (1)

[Claims] 1. A filter body into which the metallurgical molten slag is introduced, a plurality of front and rear stirring blades that transport the introduced metallurgical molten slag as granules out of the filter body while stirring it, and a filter body that absorbs the radiant heat of the metallurgical molten slag in the filter body. A metallurgical slag granulation and heat recovery device equipped with a water-steam conversion passage.