JPS62212250A - Wind-granulating and heat-collecting apparatus for non-ferrous refinement molten slag - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention produces granular slag by blowing it away with a high-speed airflow ejected from a nozzle of non-ferrous smelting molten slag in an atomizing box, that is, crushing the molten slag. This relates to a non-ferrous smelting molten slag blowing and heat recovery device that recovers the heat held by the gas by heat exchange between the gas blown into the box and the flying granular slag, and in particular recovers higher temperature gas. In order to do this, the surrounding wall of the atomizing box is partially or entirely formed into an air-cooling jacket structure.

By blowing the preheated gas flowing out of the air cooling jacket into the atomization box, a higher temperature gas than before can be obtained.

Background of the Invention The amount of iron smelting slag and non-ferrous smelting slag such as copper, zinc and lead produced in Japan is enormous every year. Conventionally, these slags have been used for many purposes such as cement raw materials, landfill materials, road paving materials, and building materials after being pulverized. However, pulverizing such molten slag as it is wastes the thermal potential possessed by the molten slag, which is a serious loss from the viewpoint of energy conservation. Therefore, there is increasing interest in producing granular slag with a size and shape suitable for the above-mentioned uses while efficiently recovering the heat possessed by the molten slag.

Wind crushing technology is one of the effective methods for granulating molten slag while recovering the heat it possesses. this is,
The molten slag introduced into one end of a chamber called an atomization box or granulation chamber is blown with a high-speed air stream ejected from a nozzle located near the molten slag to granulate the slag.

The granulated slag particles diffuse and fly inside the atomizing box, fall to the bottom of the atomizing box, and are collected by a particle receiving device installed there. The wall of the atomization box has a water-cooled jacket structure or a boiler structure with water tubes lined up, so that the granular slag flying inside the box receives heat by radiation, and the granular slag in direct contact with the wall VC receives heat by heat transfer. Collect. It has also been proposed to introduce room-temperature gas into the box through a granule receiving device, raise the temperature of the gas during the rise through flying granular slag groups, and effectively utilize the high-temperature exhaust gas from the top of the box. Even in this case, the above-mentioned jacket structure or boiler structure is often used for the purpose of preventing the colliding flying slag particles from adhering to the wall surface and for the purpose of heat recovery. Someday K
However, in the conventional technology, the main method is to make the wall of the atomization box a water-cooled jacket structure or a boiler structure, and to recover heat by using the steam generated by the heat transferred there for, for example, operation of a steam turbine. It was a heat recovery method.

However, there are situations in which it is desirable to recover the heat held by the bath molten slag as a high temperature gas rather than as steam. For example, many smelters that produce molten slag are equipped with hot air furnaces, and it may be advantageous to use the exhaust gas from the atomization box as the hot air supplied to the furnace. The exhaust gas in a conventional flK is insufficient in temperature to be the high temperature gas desired in such a situation.

Purpose of the Invention In order to meet the above-mentioned demand for obtaining high-temperature gas,
The present invention aims to develop a molten slag crushing/heat recovery device that can produce gas at a higher temperature than the conventional one as atomized box exhaust gas.

Summary of the Invention When the purpose is to recover the sensible heat of molten slag as a high-temperature gas, the wall of the atomization box has a water-cooled jacket structure or a boiler structure, and the heat transferred there by KSL injection or heat transfer can be transferred to water or The conventional concept of recovery as water vapor must be rejected. The inventor of the present invention recovered the heat transferred by radiation or heat transfer with gas by adopting an air-cooled jacket structure, and then blown the heated gas into the atomization box to prevent it from flying. The idea was to collect the slag from the top of the box after contacting it with the granular slag, and as a result of tests, good results were obtained. The air-cooled jacket structure may be used around the entire perimeter wall of the atomization box, or may be used in combination with a water-cooled jacket structure or a boiler structure. In general, water cooling is required for parts of the box where flying slag particles collide violently, for example, the rear wall of the box. In this way, the amount of heat recovery is increased by the sensible heat of the heated gas obtained from the air cooling jacket, making it possible to obtain gas at a higher temperature than before.

In this way, the present invention atomizes nonferrous smelting molten slag in an atomizing box, collects the granular slag after being dispersed, and recovers the heat contained in the granular slag. fin: The entire surrounding wall of the atomization box has an air-cooling jacket structure, or
Alternatively, the surrounding wall is combined with a water-cooling jacket structure or a boiler structure, and blowing means is provided for blowing the preheated gas flowing out from the air-cooling jacket into the atomization box, and the preheated gas is blown into particles flying inside the atomization box. Provided is a non-ferrous smelting molten slag blowing and heat recovery device characterized in that a high-temperature gas outlet is provided at the top of the atomization box to recover the high-temperature gas after heat exchange with the slag.

In addition, in this specification W, the boiler structure refers to one in which the wall of the atomization box itself is arranged in a water tube pattern, or one in which water tubes are arranged in a staggered pattern in front of the nuclide to prevent slag from sticking. Wrapping up things made up of
summarize. Regarding the former, there are two types: a structure in which water tubes are welded together, and a structure in which fins of a finned water tube are welded together. The latter consists of multiple rows of water pipes arranged in a staggered pattern in front of the wall (which may be in contact with the wall or may be spaced apart from it), and the welded parts between the water pipes and the fins or between the fins. By eliminating this, the problem of refusion of flying slag particles is solved.

Therefore, in the present invention 8A, the following structure can be adopted for the atomization box surrounding wall: (a) The entire surrounding wall has an air-cooled jacket structure (b) Air-cooled jacket + water-cooled jacket structure High-temperature gas in the present invention is a general term for gases with a temperature higher than room temperature, including hot air. Depending on the application, it can produce extremely high temperature gas, or it can efficiently produce large quantities of relatively low temperature hot air. By widening the area of the air cooling jacket, it is possible to increase the recovery rate of hot air.

DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows an atomization box 1 in a molten slag crushing and heat recovery apparatus. For example, in the case of non-ferrous smelting slag, molten slag at a temperature of 1200-1300'C is introduced through the downflow trough 3 at the front end wall 201C of the box 1. As shown in FIG. 3, an atomizing nozzle 5 for atomizing molten slag is provided in the lower part of the gutter 3. The granular slag, which is granulated by the gas jet, which is generally high-pressure air, ejected from the nozzle, flies inside the atomization box in the axial direction of the nozzle, and gradually solidifies as it flows toward the bottom of the atomization box. Fall. A particle receiving device is installed at the bottom of the atomization box. The granule receiving device is shown here as having a structure in which four wind boxes 7 each having an inclined perforated plate or wire mesh 6 on the upper surface are arranged side by side, and a chute 9 is installed adjacent to each wind box to drop the granular slag. Any structure can be used as long as it can efficiently transport the granular slag that is generated and deposited out of the box. As shown in FIG. 2, the 5Vc atomizing box has a lower part shaped like an inverted cone, and the falling granular slag is deposited on a perforated plate. The gas ejected through the perforated plate, which will be described later, prevents the granular slag deposited there from fusing together, fluidizes it, and promotes its migration toward the shoe 9. The slag particles falling from the chute 9 are conveyed by a suitable conveying device, for example a vibrating conveyor, and, if necessary, after recovering their residual heat, are recovered as pulverized slag. The ground slag thus obtained is fine with an average particle size of about 11,111.

On the other hand, in order to recover heat from the air-crushed slag, conventionally the walls of the atomized box have a water-cooled jacket structure or a boiler structure with an array of water pipes, and the heat inside the box is recovered as high-temperature water or steam. However, this is disadvantageous for producing high-temperature gas, which is the object of the present invention. Therefore, according to the present invention, at least a portion of the surrounding wall of the atomization box is configured as an air cooling jacket 12, as shown in FIG.

A room temperature gas, such as air, is introduced into the air cooling jacket 12 through an inlet 14, here located in the box ceiling. The air cooling jacket is attached to the wall surrounding the box, i.e. the ceiling,
It may be formed on both end walls and the entire side walls, or the parts such as the rear end wall 21 of the box where the flying slag hits hard may have a water-cooled jacket or boiler structure, and the rest may have an air-cooled jacket structure. In any case, the introduced ambient temperature gas flows through the air-cooled jacket passage to the outlet 16, during which time the temperature increases. The preheated gas flows into a blowing means which blows it inside the atomization box. In this specific example, the blowing means is configured as the above-mentioned wind box 7, but
Alternatively, an appropriate gas inlet may be installed at or near the bottom of the box.

Alternatively, it may be blown into the box via a blower. After that, the gas passes through a perforated plate installed on the top surface of the wind box, fluidizes the granular slag deposited there, and after exchanging heat with them, comes into contact with the granular slag flying inside the box, Finally, it flows out through the outlet 18 provided on the upper wall of the atomization box. In order to avoid entrainment of granular slag, the discharge port 18 is preferably provided on the upper wall of the atomization box, and closer to the front end wall 20 or the rear end wall 21 of the atomization box.

The gas is heated mainly by radiant heat from inside the box while passing through the air cooling jacket 12, and then heated through direct heat exchange with the granular shot while rising inside the box. The high-temperature gas obtained in this way is used for hot stoves and other purposes.

When designing an atomization box, the length and width of the box are determined by taking into consideration the flight distance and width of granular slag during slag crushing, but generally speaking, the box length and width are determined by reducing the installation cost of the atomization box. In order to keep the internal atmosphere as high as possible, boxes are often made smaller. In such a case, the end wall of the box opposite to the side where the nozzle is provided, that is, the rear end wall of the box and both side walls near it, are bombarded by flying slag particles. Slag grains with a temperature of 900°C or higher tend to stick to the walls unless they are water-cooled. Under such circumstances, the box walls are constructed with water-cooled jackets or boiler structures, and the remaining box walls are constructed with air-cooled jackets. Structure. However, if it is permissible to make the box large enough to prevent slag particles from hitting the rear end wall of the box and both side walls near it, the entire surrounding wall of the box may have an air cooling jacket structure.

The inlet for introducing room temperature gas into the air cooling jacket is shown here as one on the ceiling, but it is possible to provide multiple inlets,
For example, gas may be introduced into the end wall and side wall 51C1. The amount of gas fed to each inlet can also be varied depending on the cooling requirements.

A suitable baffle plate can be provided inside the air cooling jacket to adjust the gas path length. It is also possible to divide the box wall into several sections depending on the cooling requirements, and to vary the gas path length for each section.

As described above, in the present invention, the entire surrounding wall of the atomization box may have an air-cooled jacket structure, or the air-cooled jacket+water-cooled jacket structure may be an air-cooled jacket+boiler structure. Boiler structure binding
As shown in Figure 4(a), the wall of the atomization box itself can be constructed by arranging water pipes, or as shown in Figure 4(b), multiple rows of torpedoes are arranged in a staggered pattern in front of the wrinkled wall. It may be configured as follows. The latter is effective in preventing refusion of slag particles since there is no weld seam.

Effects of the invention: When recovering heat from non-ferrous smelting molten slag, gas at a higher temperature than before can be recovered, which provides great benefits for situations that require high-temperature gas. In particular, one of the great advantages of the present invention is that the hot air recovery rate can be increased.

EXAMPLE An air cooling jacket with an inner area of tsm was installed on the ceiling and side walls of an atomized box having the form shown in the drawings. Steel heavy blast furnace slag at 1200℃ (L7~t
1 to 9/cII? It was crushed by G's atomized air. air cooling jacket) K is 15 Nm”7 for air at a temperature of 25°C.
I injected it at a flow rate of 1 minute. The exhaust gas temperature when not using the air cooling jacket was 400°C, but when using preheated air with the air cooling jacket, the exhaust gas temperature was 70 to 15°C.
Increased by 0°C.

4 Brief Description of the Drawings Figure 1 is a schematic diagram of the atomization box, and Figure 2 is a schematic diagram of the atomization box.
The figure is a schematic sectional view taken along the line XX in FIG. 1. FIG. 3 is an explanatory diagram showing a situation in which slag flowing down from a downflow gutter is crushed by air jets from an atomizing nozzle. Fourth (
Figures a) and (b) show examples of boiler constructions.

1: Atomize box 3: Gutter 5: Atomize nozzle 6: Porous inclined plate 7: Wind box 9: Shoot 12: Air cooling jacket 14.16: Entrance, exit 18: Discharge port 20.21: Front end wall, rear end wall Figure 3

Claims (1)

[Claims] 1) A molten slag blow crushing and heat recovery device that crushes non-ferrous smelting molten slag in an atomizing box, recovers the granular slag after being dispersed, and recovers the heat contained in the granular slag. In this case, the entire surrounding wall of the atomizing box has an air-cooled jacket structure, or the surrounding wall has a combination of an air-cooling jacket structure and a water-cooling jacket structure or a boiler structure, and the preheated gas flowing out from the air-cooling jacket is transferred to the atomizing box. A blowing means is provided for blowing the preheated gas into the atomizing box, and a high temperature gas outlet is provided at the top of the atomizing box to recover the preheated gas as a high temperature gas after exchanging heat with the granular slag flying within the atomizing box. Wind crushing and heat recovery equipment for non-ferrous smelting molten slag. 2) The device according to claim 1, wherein the boiler structure is constructed by arranging water tubes on the atomization box wall itself or by arranging water tubes in a staggered pattern in front of the wall.