JPS587121B2 - Equipment that generates high pressure steam from molten slag - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for generating high-pressure steam from high-temperature molten slag discharged from a blast furnace or the like.

Conventionally, the molten slag discharged from the melting furnace was either cooled by water and then dumped, or the heat of the slag was transferred to gas and the heat was recovered in a normal boiler.

In the former case, a large amount of heat contained in the molten slag is dissipated into the atmosphere, which is extremely important from an energy saving perspective, and in the latter case, the thermal energy contained in the molten slag can be recovered. First, because it relies on the procedure of slag -> gas -> boiler, it has the disadvantage of being inefficient and requiring a huge heat transfer surface.

The present invention was invented in view of the current situation, and aims to provide a small and efficient steam generator that recovers heat from molten slag in the form of high-pressure steam. The present invention is characterized in that the heat possessed by molten slag is recovered in three stages: superheated steam, saturated steam, and preheating of feed water.

Next, one embodiment of the present invention will be described with reference to the drawings.

1 is the boiler body. It has a hopper shape, and a small diameter water preheating casing 12 is connected to the lower end.

A superheated steam casing 10 is provided in the upper part of the boiler body 1, and the superheated steam casing 10 penetrates through the upper body 1 and opens above the boiler water 20 in the body 1.The upper end of the casing 10 is supplied with molten slag in the form of particles. For example, a hopper 4 for introducing molten slag and a rotary feeder 6 connected to the hopper 4 are attached.

The feeder 6 consists of a drum rotatably mounted within the casing 5, and a recess is bored in the outer periphery of the drum so that it can rotate counterclockwise.

In addition, the boiler body 1 includes boiler water 20 inside the boiler body.
A saturated steam take-off pipe 25 that opens upward and a superheated steam take-off pipe 24 that penetrates the boiler body 1 and opens into the superheated steam casing 10 are provided.

In the figure, the superheated steam outlet 24 and the saturated steam outlet pipe 25 are shown concentrically, but the present invention is not limited to this, and each may be provided independently.

A screw 13 for adjusting slag discharge is provided inside the water supply preheating casing 12, and a slag discharge rotating rotor 15 is rotatably mounted on the lower end of the screw 13.

Reference numeral 17 denotes a water supply pipe, which opens at the lower end of the water supply preheating casing 12 via a water supply control valve 18, and a branch pipe 23 thereof.
is opened into the steam superheating casing 10 via the water injection control valve 22 for superheating temperature adjustment. In the figure, 14 is the rotor 1.
A rotor casing 5 is rotatably mounted, 16 is a recess formed in the rotor 15, and 11 is a dispersion plate.

Next, the operation of this device will be explained.

When slag is injected into the hopper 4 in a fluid state 2, the slag accumulates in the hopper 4 in the state shown by 3, and is gradually poured into the recess T of the feeder 6 from below the hopper 4 in small quantities.
It is filled as it rotates.

As the feeder 6 rotates, the slag 8 filled in the recess T passes through the steam superheated casing 10 and becomes granular slag 9.
and falls into the boiler body 1.

Water is injected into the boiler body 1 to the level shown at 27, and the slag 9 that has fallen into the boiler body 1 directly contacts the surrounding boiler water 21' and transfers heat to the water, causing the water to rise. Upon boiling, the slag itself solidifies.

The solidified slag 9 further continues to fall within the boiler main body 1, comes into contact with the distribution plate 11, and is widely dispersed within the boiler main body 1.

Then, it falls into the water supply preheating casing 12 and heats the water 20 injected there, and finally the screw 1
3, it is sent to the rotor 15, sequentially filled into the recesses 16 of the rotor 15, and discharged to the outside of the casing 12 as the rotor 15 rotates.

A portion of the water supplied from the water supply pipe 17 is preheated with slag in the preheating casing 12 and rises toward the boiler body 1, where it comes into direct contact with the high-temperature slag. This becomes saturated steam 21, which is regulated by a valve 26 and taken out through a pipe 25.

Further, another part of the feed water is supplied into the superheated steam casing 10 through the branch pipe 23, where it comes into contact with the extremely high temperature slag and becomes superheated steam 21', while a part of the saturated steam 21 21A The superheated steam also enters the superheated steam casing 10 and comes into contact with the high temperature slag to become superheated steam 21', and both are taken out from the superheated steam extraction pipe 24.

The saturated steam 21 and the superheated steam 21' may be used separately outside the system, or the mixed steam 21' may be used separately as shown in the figure.
It can also be used as 1'.

In this way, in this device, molten extremely high-temperature slag is first brought into direct contact with feed water to turn it into superheated steam, and through this heat exchange, the solidified slag rises from below inside the boiler body. The feed water is made to fall opposite to the incoming feed water to turn the feed water into saturated steam, and a portion of this saturated steam is brought into contact with high temperature slag to obtain superheated steam.

Furthermore, since the slag is taken out from the casing after the feed water supplied to the boiler body 1 is preheated in the feed water preheating casing, the heat of the molten slag discharged from the blast furnace is recovered in the form of steam. That will happen.

As mentioned above, this device has good efficiency because the heat possessed by the slag is recovered in each of the three stages of superheated steam generation, saturated steam generation, and feed water preheating. Despite its small size, it can recover a large amount of heat.

Further, since the slag is discharged from the casing in the form of granular solids, subsequent handling becomes extremely easy.

[Brief explanation of drawings]

The figure shows one embodiment of the invention. 1...boiler body, 4...hopper, 6
... Rotating feeder, 10 ... Superheated steam casing, 12 ... Water supply preheating casing, 15 ... Slag discharge rotating rotor, 17 ...
... Water supply pipe, 21 ... Branch pipe, 24 ...
...Superheated steam takeoff pipe, 25...Saturated steam takeoff pipe.

Claims (1)

[Claims] 1 Consists of a boiler body with a small-diameter feedwater preheating casing extending downwards, and a superheated steam casing that penetrates through the top of the boiler body and opens above the boiler water in the boiler body, and converts molten slag into particles. A device for supplying the superheated steam into the boiler main body via the superheated steam casing is provided on the superheated steam casing, and a saturated steam extraction pipe opens above the boiler water in the boiler main body, and a saturated steam extraction pipe that penetrates the boiler main body and supplies the superheated steam to the boiler main body. Superheated steam take-off pipes opening in the steam casing are provided, water supply pipes are provided leading to the feedwater preheating casing and the superheated steam casing, and a rotor for discharging granular slag that has fallen into the feedwater preheating casing is connected to the feedwater preheating casing. A device for generating high-pressure steam from molten slag, characterized by being installed at the lower end of a casing.