JPS591227B2 - Method and device for producing spherical expanded slag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for producing light spherical slag with few surface pores using blast furnace slag as a raw material.

Conventionally, blast furnace slag has the property of expanding when the sulfides in the slag are oxidized when cooled, and many people in various places have conducted research to utilize this property to create expanded slag. However, the problem of not leaving many pores at the interface and making it spherical has not been solved, and the reality is that this has remained the case to this day.

Originally, blast furnace slag was made into spherical expanded slag with few surface pores because the S contained in the slag oxidized and expanded in the atmosphere during cooling as described above. The method of obtaining it comes down to problems with cooling and dispersion techniques.

As a result of reviewing the prior art from this perspective, the present invention found that the main causes (inability to obtain a spherical expanded slag with few surface pores) are the control of slag temperature, viscosity, slag flow rate, flow shape control, and I learned that there were problems with the control of water volume and the method of dispersing water over long distances.

The present invention solves the above-mentioned problems and relates to a method and apparatus for manufacturing spherical expanded slag with few surface pores. The blast furnace slag flows into the upper opening of the curved gutter, which has multiple water holes in the side wall, and is forcibly dispersed into the atmosphere at the lower opening of the curved gutter, which is open to the atmosphere. A method for producing a spherical expanded slag characterized by: vertically inserting a curved gutter having a plurality of water flow holes through the circumferential side wall in a water tank, and an upper opening of the curved gutter. The lower part communicates with a horizontal gutter protruding from the blast furnace slag receiving hopper adjacent to the water tank, while the lower opening is open to the atmosphere, and the lower opening of the curved gutter is connected to the horizontal gutter. This is an apparatus for manufacturing spherical expanded slag, characterized in that a blower for scattering blast furnace slag is installed in the slag.

Embodiments of the present invention shown in the drawings will be described below.

In the drawing, 1 is a slag ladle, 2 is a slag receiving hopper, 3 is an outlet of the hopper, 4 is an outflow adjustment damper provided at the outlet, and 5 is a fitting for the outlet following the outlet. The larger horizontal gutter, 6, is the flow rate installed near the tip of this horizontal gutter (
7 is a curved gutter having a plurality of water flow holes 8, 9 is an upper opening, 10 is a lower opening, 11 is a water tank, 12 is a steam cylinder, 13 is a water supply pipe, 14 is a centrifugal blower,
15 is a centrifugal blower, 16 is an unloading conveyor, 17 is a drain, 18 is a scattering chamber, 19 is a ventilation device, 20 is a hole for fixing a flow rate (thickness) adjustment plate, 21 is an insertion pin, 22 is a caster,
23 indicates slag.

With the above configuration, the receiving and discharging hopper 2 for adjusting the flow rate, flow velocity, flow shape, etc. of the flowing slag, such as the slag ladle, is provided close to the slag ladle, etc., and the outlet 3 of this hopper is provided. An outflow adjustment damper 4 is provided to adjust the flow rate, flow velocity, flow shape, etc. of the slag flowing out from the hopper 2.

Further, following the hopper outlet 3, a horizontal gutter 5 with a larger inner fitting than the outlet is provided in order to moderate the flow velocity of the slag flowing out from the hopper and make the flow rate thinner, and a twill-shaped groove is provided at the tip of this horizontal gutter. Flow rate (thickness) that adjusts the thickness of the flow into the curved gutter 7
An adjustment plate 6 is provided.

As described above, the molten slag flowing down from the slag pot etc. is adjusted to a constant flow rate, flow rate, and flow shape, and flows into the twilled curved gutter 7, and is heated to a predetermined temperature by the method described later while flowing down the gutter. It is something that is cooled.

The diameter of this gutter is preferably the same as the slag flow shape, and if the thickness of the slag flowing down is small, it is sufficient to make only a part of the vertical shape vertical, as shown in Figure 5. When the amount of molten slag is large, it is preferable to have a bend as shown in FIG. 1, since the front and back sides of the slag can be cooled evenly.

Further, a plurality of water holes 8 are provided in this curved gutter.

This water hole expands the heat content of the slag at (near) the time it flows into the gutter to the maximum at the time it flows out from the gutter, but at the same time as dispersion, surface tension acts to the minimum level necessary to form a spherical shape. It is provided so that the necessary amount of water flows in order to maintain the abominable heat content (hereinafter referred to as the minimum abominable heat content).

In addition, it is preferable to make the water flow holes as small as possible and to increase the number of holes.Furthermore, the diameter of the gutter should be increased as it goes downward, and the size of the water tank should be determined based on the required water volume and required flow rate (depending on the slag falling flow rate). It is preferable to decide in relation to (make them equal).

The minimum amount of heat content can be determined by, for example, setting the heat content of the inflowing slag in advance from the actual temperature and specific heat, determining the amount of water required to make this heat content the minimum amount of heat content, and then determining the amount of water that actually flows into the slag. If the heat content of the slag is different from the set heat content, you can adjust the flow rate of the slag by operating the flow rate (thickness) adjustment plate 6 to keep it almost constant without changing the water volume. It is something.

It goes without saying that the amount of water required to achieve the minimum amount of heat content must be set after determining the actual amount of steam generated, the temperature of the water before and after use, the amount of heat dissipated in the flow down the gutter, etc. do not have.

The molten slag that has flowed into the curved gutter as described above flows down while being sprayed with the required amount of water from the plurality of inlet holes 8 provided at regular intervals, leaving a minimum amount of heat content in the lower part. The particles reach the opening 10, are dispersed into particles in the air by the centrifugal blower 14 installed below, solidify into a spherical shape due to surface tension, and then ride the 16 delivery belts and are transported to a predetermined location. It is something.

In this case, the important thing is that if the time that the scattered particles remain in the air is short, the time for surface tension to act is also short, making it difficult to form a spherical shape and causing re-fusion. The idea is to set the angle of the air so that it stays in the air for a long time.

This angle can be obtained by adjusting the lower limit to the horizontal direction and the upper limit to the direction of 21 degrees to the horizontal, that is, by adjusting the range between the upper limit and the lower limit, but it will vary depending on the size of the scattering chamber, how the scattering chamber is installed, the position, etc. .

As described above, according to the method of the present invention, a gutter for flowing down blast furnace slag in a water tank is inserted vertically, and the gutter is curved, and the circumferential side wall of the gutter is Since many water holes are installed through the blast furnace, the blast furnace slag flowing down can be cooled evenly throughout, making it possible to create a light, spherical expanded slag with few surface pores.

In addition, the device of the present invention can efficiently produce the above-mentioned expanded slag.
And it can be done safely.

Examples will be described below.

Example The raw material used in this example was blast furnace slag having the following composition.

This blast furnace slag is collected using a device having roughly the same structure as shown in Figure 1, except that the diameter of the outlet of the slag receiving hopper is 150% x 1.
00%, by using the outflow adjustment damper 4, the diameter of the outflow port is 50% x 60%, and the horizontal gutter 5 connected to this is 600% long and 250% wide, however, casters are not installed in this horizontal gutter. At the same time as coating, a convex part is provided so that the slag spreads while stopping and flows slowly.The actual flow rate of the slag is approximately 200%, and the flow rate (thickness) adjustment plate 6 is adjusted to a flow rate thickness of 15%. The diameter of the inlet of gutter 7 is 250% x 100%,
250% x 125~2 from around 300% or less from the inlet
Gradually expand to 00%.

The length is approximately 1250%, the bending angle is 40° to the horizontal, the injection angle is 20° to the horizontal, the cross-sectional diameter of the water outlet hole 8 and the number of holes are 13% in the upper row. Middle row 7% 26 pieces, lower row 5% 26 pieces, temperature of water used is 21℃, amount of water used is slag temperature 1350℃ (heat content 367cm/IKg) 0.7 per ton
The centrifugal blower has an air volume of 600 rr under conditions of 93 m3 and a slag flow rate of approximately 30 tons/h? /min, pressure 250% Ag was used.

The slag produced under this condition is an almost spherical expanded slag with low surface porosity, and the particle size is 0.5 to 2.5% with a particle size of 15% or more.
4%, 15% or less, 5% or more is 10.2-16.3%, 5
% or less, 81 to 89 inches, absolute dry specific gravity 1.45 to 1.6, capacity 0.75 to 0.80 for coarse aggregate (15% to 5%), and 1 for fine aggregate (5% or less). .0 to 1.09, and the performance rate was 50 or higher, and the number of unexpanded slags and incompletely expanded slags of spherical shape was negligible.

As described above, according to the present invention, a spherical expanded slag that is light and has few surface pores can be obtained, so that it can be used as a lightweight aggregate for concrete slabs, structural concrete aggregates for high-rise buildings, and other insulating materials. It can be effectively used for roadbed materials, etc.

[Brief explanation of the drawing]

Fig. 1 is a plan view of the device of the present invention, Fig. 2 is a sectional view taken along line A-A in Fig. 1, Fig. 3 is an enlarged plan view of the horizontal gutter portion, and Fig. 4 is a horizontal gutter and a curved gutter. Partial cutaway explanatory diagram of the part, No. 5
The figure is a partially cutaway explanatory diagram when a part of the curved gutter is made vertical. In the figure, 1... slag pot, 2... slag receiving hopper. 3...Hopper outlet, 4...Outflow adjustment damper, 5...Horizontal gutter, 6...
Flow rate (thickness) adjustment plate, 7... Curved gutter, 8...
...Water hole, 9...Top opening, 10...
... lower opening, 11 ... water tank, 12 ...
...Steam cylinder, 13...Water supply pipe, 14...
... Centrifugal blower, 15 ... Centrifugal blower, 1
6... Carrying out conveyor, 17... Drain pipe, 18... Scattering room, 19... Ventilation device.

Claims (1)

[Scope of Claims] 1. Blast furnace slag flows into the upper opening of a curved gutter that is vertically inserted into a water tank and has a plurality of water flow holes through the circumferential side wall, and is released to the atmosphere. A method for producing spherical expanded slag, characterized in that the blast furnace slag is forcibly scattered into the atmosphere at a lower opening of a curved gutter. 2 A curved gutter with a plurality of water holes penetrating the circumferential wall is vertically inserted into the water tank, and the upper opening of the curved gutter is connected to the blast furnace slag receiver installed adjacent to the water tank. It communicates with a horizontal gutter that protrudes from the hopper, while the lower opening is open to the atmosphere, and a blower for scattering blast furnace slag is installed near the lower opening of the curved gutter. An apparatus for manufacturing spherical expanded slag, which is characterized by: