JPH09208274A - Water granular for molten slag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a water granular for molten slag capable of obtaining a clean and stabilized granulated slag reduced in the deposition of heavy metals on the surface. SOLUTION: The molten slag discharged from the slag outlet 2 of a melting furnace 1 is water-granulated by this device. A water tank 11, a scraper conveyor 21 set in the water tank 11 and a water sprinkler 21 above the draining part 14 of the conveyor 21 are provided, and the water B stored in the tank 11 is filtered, regulated to >=pH7 and supplied to the sprinkler 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water granulation device for molten slag. Municipal waste, sewage treatment sludge, industrial waste, etc.
Various wastes are melted directly in a melting furnace or after being incinerated in order to reduce the volume and stabilize them. When such waste material is melt-processed in a melting furnace, molten slag is produced, and the molten slag is discharged from a slag discharge port provided on the furnace wall of the melting furnace. Since the molten slag discharged from the slag discharge port cannot be handled as it is, it is generally granulated into water granulated slag. The granulated slag is either landfilled or used as a civil engineering building material, etc. In any case, the granulated slag is required to have little adhesion of heavy metals. TECHNICAL FIELD The present invention relates to a water granulation device for molten slag capable of obtaining a water granulated slag with less adherence of heavy metals.

[0002]

2. Description of the Related Art Conventionally, as a water granulating device for molten slag, one having a water tank installed facing the slag discharge port and an endless or screw type scraping conveyor equipped in the water tank has been used. ing. This water granulation device stores water in a water tank, drops molten slag discharged from the slag discharge port into the stored water to water granulate, and then scrapes the water granulated slag from the water tank by a scraping conveyor. . In this case, in order to improve water granulation efficiency, a nozzle is attached between the slag discharge port and the water tank, and water is jetted from the nozzle to the molten slag that is in the process of falling. However, according to such a conventional slag water granulating device, heavy metals are easily attached to the water granulated slag discharged from the water granulated water tank due to heavy metals in the water granulated water contaminated by the water granulation of the molten slag. There is a drawback that. Heavy metals adhering to the surface of the granulated slag are not stabilized and easily eluted, which may hinder the effective use of the granulated slag.

[0003]

The problem to be solved by the present invention is that heavy metals are easily attached to the water granulation slag obtained by the conventional water granulation device.

[0004]

DISCLOSURE OF THE INVENTION The present invention, however, is an apparatus for water granulating molten slag discharged from a slag discharge port of a melting furnace, which comprises a water tank, a scraping conveyor provided in the water tank, and A water slag granulating device, characterized in that a water sprinkler is provided above the water draining part of the scraping conveyor, and the filtered water of the stored water in the water tank adjusted to PH7 or higher is supplied to the water sprinkler. Pertain.

In the present invention, the water tank is installed under the slag discharge port of the melting furnace. This aquarium is formed into a generally inverted trapezoidal shape when viewed from the front, and therefore has an inclined surface that is continuous with the bottom surface. The inclined surface serves as a scraping surface when the granulated slag in the water tank is scraped out of the water tank by the scraping conveyor. The upper part of the scraping surface above the stored water in the water tank serves as a draining part of the scraping conveyor. In this scraping conveyor, a plurality of scrapers are usually mounted on a pair of endless chains at predetermined intervals, and the scrapers rotate inside and outside the water tank while sliding on the bottom surface and the scraping surface of the water tank. A screw type conveyor may be used as the scraping conveyor. The screw installed along the scraping surface rotates. When the screw is provided, there is almost no bottom surface of the water tank. In the present invention, a water sprinkler is provided on the upper surface of the draining section of the scraping conveyor as described above, and the washing water is sprinkled on the granulated slag rising from the draining section.

As the washing water sprinkled from the upper part of the draining section of the scraping conveyor of the water tank, the water stored in the water tank adjusted to PH7 or higher is used. With normal water,
This is because the amount of wastewater to be treated increases as a result. On the other hand, even if the stored water is contaminated with heavy metals due to the water granulation of the molten slag, most of the heavy metals in the stored water are in the form of particles if the pH of the stored water is 7 or more. Since it exists, heavy metals can be removed by filtering the stored water, so the filtered water contains almost no heavy metals and can be used as washing water, in which case the amount of wastewater to be treated does not increase. Is.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an overall vertical cross-sectional view illustrating a water granulator according to the present invention in relation to a melting furnace. In FIG. 1, various kinds of waste such as municipal solid waste, sewage treatment sludge, and industrial waste are reduced in volume and stabilized in an arc type melting furnace 1, and thus molten slag is produced directly or after incineration. The generated molten slag is discharged from the slag discharge port 2 formed in the furnace wall of the melting furnace 1.

A water tank 11 is installed below the slag discharge port 2 of the melting furnace. The water tank 11 is formed in a substantially inverted trapezoidal shape when viewed from the front, and therefore has an inclined surface continuous with the bottom surface 12, and this inclined surface removes the water granulated slag A in the water tank 11 by the scraping conveyor 21 described later.
It becomes the scraping surface 13 when scraping from the surface. An upper part of the scraping surface 13 above the stored water B in the water tank 11 serves as a draining part 14 of the scraping conveyor 21.

The water tank 11 has an endless scraping conveyor 21.
Is equipped. On the scraping conveyor 21, a plurality of scrapers are mounted on a pair of endless chains (not shown) at predetermined intervals, and the scrapers are attached to the bottom surface 1 of the water tank 11.
While sliding on the 2 and the scraping surface 13, the water tank 11 rotates inside and outside. The granulated slag A is scraped up by the scraper. A sprinkler 22 is provided above the scraping surface 13.

An intake pipe 31 is connected to the water tank 11, and a filter 33, for example, a pleco type filter is connected to the intake pipe 31 via a pump 32.
Is connected to the sprinkler plug 22 via a water supply pipe 34. Even if the stored water B is contaminated due to the water granulation of the molten slag, if the PH of the stored water B is 7 or more, most of the heavy metals in the stored water B exist in the form of particles. B is supplied to a filter 33 through a water pipe 31 and a pump 32, and heavy metals present in the form of particles in the stored water B are removed by filtering with the filter 33, and purified filtered water is supplied. Supply to the sprinkler 22 via a pipe 34. Aquarium 1
The water granulated slag A in 1 is scraped up along the scraping surface 13 by the scraping conveyor 21, washed with the above-mentioned purified filtered water sprayed from the sprinkler 22 in the draining section 14, and adheres to the surface thereof. Heavy metals are removed.

Although an arc type melting furnace is used as the melting furnace in FIG. 1, the melting furnace may be of any type such as plasma arc furnace, resistance furnace, induction furnace, shaft furnace, burner melting furnace and the like. In addition, although the pleco type is illustrated as the filter in FIG. 1, the filter may be a sand filter type, a cartridge filter type, or the like.

[0012]

As is apparent from the above, the present invention described above has an effect that it is possible to obtain a clean and stabilized granulated slag in which heavy metals are less attached to the surface.

[Brief description of drawings]

FIG. 1 is an overall vertical cross-sectional view illustrating a water granulation device according to the present invention in relation to a melting furnace.

[Explanation of symbols]

1 ... Melting furnace, 2 ... Slag discharge port, 11 ... Water tank, 12 ... Bottom surface, 13 ... Scraping surface, 14 ...
・ Drainer, 21 ... Scraping conveyor, 22 ...
Sprinkler, 31 ... Intake pipe, 32 ... Bomb, 33 ...
..Filters, 34 ... Water supply pipes, A ... Granulated slag,
B ... Reserved water

Claims (1)

[Claims] 1. An apparatus for water-splitting molten slag discharged from a slag discharge port of a melting furnace, comprising a water tank, a scraping conveyor provided in the water tank, and a water sprinkler on an upper part of a draining portion of the scraping conveyor. And a water granulation device for molten slag, wherein filtered water of the stored water in the water tank adjusted to PH7 or higher is supplied to the sprinkler.