JPH02172533A - Method for treating minerals - Google Patents

Abstract

PURPOSE:To efficiently separate objects to be recovered which have been vaporized and minerals not to be recovered which are not vaporized by heating minerals to be treated in a combustion furnace to vaporize objects to be recovered, causing said objects to flow downward and further causing them to flow upward. CONSTITUTION:By burning fuels with oxygen or oxygen-enriched air, temperature within a combustion furnace 8 is raised up to a vaporizing or decomposing temperature or higher of objects to be recovered in minerals 1b to be treated. Particles of the minerals 1b are introduced into the combustion furnace 8 so that the objects to be recovered are vaporized and caused to flow downward together with combustion gas and then are caused to flow upward, whereby components 5 on the particles of the minerals 1b which have not been vaporized are caused to flow downward, while components 6 having been vaporized are caused to flow upward. As a result, separation of vaporized objects to be recovered from minerals not to be recovered which are not vaporized can be effected efficiently. Further, since a high-temperature combustion furnace can be employed in place of the conventional large-capacity power-consuming electric furnace, energy unit cost can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a method for processing minerals in which a substance to be recovered in the mineral is vaporized and separated.

C. Conventional technology] Conventionally, when separating minerals by melting and vaporizing them, the separation process was performed by melting and vaporizing the minerals in a large-capacity power-consuming electric furnace (arc furnace, plasma furnace, etc.). There is.

[Problem to be solved by the invention]

Conventional technology uses large-capacity arc furnaces, plasma jet furnaces, etc. to melt and vaporize target minerals using electrical energy, which uses a large amount of electricity and consumes a large amount of electrical energy. Operational energy costs are high due to high energy unit prices.

In addition, because the furnace walls had a fireproof and insulated structure (no cooling), the furnace components were eroded, requiring periodic equipment repairs.

The present invention aims to provide a method for processing minerals that solves the drawbacks of the above-mentioned conventional techniques.

[Means to solve the problem]

The mineral processing method of the present invention involves burning fuel with oxygen or oxygen-enriched air to raise the temperature inside the combustion furnace to a temperature higher than the vaporization or decomposition temperature of the target material in the mineral to be treated, and then disposing the fuel in the combustion furnace. The target mineral powder is introduced, the target mineral is vaporized, and it is lowered together with the combustion gas, and then reversed and raised. The components that do not vaporize in the target mineral powder move downward, and the vaporized components move upward. To separate.

[Effect]

In the present invention, by burning fuel with oxygen or oxygen-enriched air, the temperature inside the combustion furnace is set to a high temperature at which the recovered substances in the minerals to be treated are vaporized or decomposed, and the minerals to be treated are transferred into the combustion furnace. By introducing the granular material, the portion to be recovered in the mineral to be treated is vaporized or decomposed and gasified.

By descending the thus treated powder, its products, and combustion gas, components that do not vaporize are captured on the combustion furnace wall, and by reversing this and raising it, the vaporization in the powder and granule is reduced. The non-volatile components and the vaporized components are completely separated, and the material to be recovered is taken out upward as a gas.
In addition, components that do not vaporize are separated downward.

In addition, the thermal efficiency can be improved by using the exhaust heat of the combustion gas taken out with the recovered materials, and if the combustion furnace wall is cooled, the molten portion of the processed minerals will be transferred to the furnace wall side. A solidified phase is formed to prevent melting of the furnace wall.

〔Example〕

A first embodiment of the present invention will be described with reference to FIG.

In this example, fine coal ash (fly ash) is the mineral to be treated, and 5i02 contained in the coal ash is used as the other component A! It relates to a method of separating from zos and the like.

The combustion furnace consists of a water or steam cooling wall 2 and a furnace wall with a refractory material 3 on the inner surface, and contains coal ash (fly ash) with an average particle size of 32-lb as the mineral to be treated, and propane gas as the fuel. ．． Alternatively, the combustion chamber 8 includes a burner 7 that blows out oxygen-enriched air 1a, and a flue 9 and a slag tap 10 through which the gas in the combustion chamber 8 reverses and rises. Burner 7 above
is eccentrically opened in the upper part of the combustion chamber 8 and generates a swirling flow 11 that descends into the combustion chamber 8.

Propane gas, which is the fuel input from burner 7, is 0.
A temperature field of 2.300°C or higher is formed, which is higher than the boiling point of Sing, which is the substance to be recovered in the above-mentioned coal ash lb, which is the mineral to be treated, at 2,230°C. Coal ash 1b with an average particle size of 32 mm, which is the mineral to be treated, is put into the combustion chamber 8, and SiO□, which is the mineral to be recovered, is vaporized (decomposed) in the descending swirling flow field in the combustion chamber 8.
However, Affi, which is a mineral that is not subject to recovery, is 0. etc. are melted. The molten AlzCh molten mineral 4 is captured by the furnace wall, and the molten mineral particles are collided with the wall and captured in the flue 9 which reverses and ascends, and the recovered object 5i02 separated in this way is vaporized. Minerals contained in the mineral-containing combustion gas 6 and not to be recovered are discharged from the slag tap 10 as molten minerals 5.

In this way, in this example, 5iO1 of fume can be separated from coal ash (flyansh).

Furthermore, the combustion chamber 8 has a water or steam cooling wall,
The molten slag such as AltCh forms a solidified phase on the furnace wall, and it is possible to prevent the refractory material 3 from being damaged. Also, 5i02
It is also possible to recover the exhaust heat of the combustion gas taken out with the gas.

In the above embodiment, propane gas was used as the fuel, but blast furnace exhaust gas containing methane, coal, or even liquid fuel can be used.

Furthermore, although 32-mm powder was used as the mineral to be treated in the above embodiments, it may be a 32-mm powder with a grain size of about 1 mm, if necessary.

A second embodiment of the present invention will be described with reference to FIG.

In this embodiment, a pressure swing detachable type oxygen production device 22 is used.
08 produced from air at a concentration of 80-90%
The temperature of oxygen-enriched air 21 is raised by a heat recovery device 23, which will be described later, and is supplied together with fuel 25 to a combustion furnace 24 having a structure similar to that of the first embodiment. On the other hand, coal ash (fly ash) 26 in the exhaust gas of the boiler 30 is collected in the air dust collector 31 and supplied to the combustion furnace 24, where it is mixed with 5IO2 gas and Alto3 etc. as in the first embodiment. Molten slag is separated. The mixture of combustion gas and 5iOz gas discharged upward from the combustion furnace 24 is collected in a collection device 32 to collect SiOx gas, and a silica fume 27 is obtained. The gas exiting the 1lli collector 32 is introduced into the heat recovery device 23 to heat the oxygen-enriched air 21, and then returned to the exhaust gas system of the boiler 30. Further, the molten slag 2B taken out from the combustion furnace 24 is separately processed to produce a high alumina product.

In this embodiment, the temperature inside the combustion furnace 24 is raised to 2,600°C by preheating the oxygen-enriched air with the heat recovery device 23.
As a result, the evaporation and vaporization of 5 iOz becomes even better.

In this embodiment, it goes without saying that Ol may be used instead of oxygen-enriched air.

(Effects of the Invention) The present invention heats the minerals to be treated in a combustion furnace to vaporize the objects to be recovered, and then lowers and then reverses the upward movement of the minerals. and efficiency (can be separated).

In addition, the present invention can apply a high-temperature combustion furnace that uses fuel and O1 or oxygen-enriched air in place of the conventional large-capacity power-consuming electric furnace, so that the unit energy cost can be reduced. Further, by employing a furnace wall having a water or steam cooling structure, it is possible to achieve effects such as eliminating the need for periodic repairs of the furnace.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a first embodiment of the invention, and FIG. 2 is an explanatory diagram showing a second embodiment of the invention. 1a - fuel and oxygen or oxygen-enriched air, lb - minerals to be treated, 2 - water or steam cooling wall, 3 - refractory material, 4.5 - molten minerals, 6 - vaporized/mineral-containing combustion gas, 7 - burner, 8- combustion chamber,
9-flue, 10.-slag tap, 21-oxygen enriched air, 22
- Pressure swing detachable oxygen production device, 23 - Heat recovery device, 24 - Combustion furnace, 25 - Fuel, 26
-Coal ash, 27--Silica hum, 28-tll
Suslag agent Patent attorney Sakama Akigai 2 people

Claims (1)

[Claims] Fuel is combusted with oxygen or oxygen-enriched air to make the temperature inside the combustion furnace equal to or higher than the vaporization or decomposition temperature of the recovered substance in the mineral to be treated, and the granular material of the mineral to be treated is introduced into the combustion furnace. A mineral characterized in that the material to be recovered is vaporized and lowered together with the combustion gas, and then reversed and raised, so that the components that do not vaporize in the granular material of the mineral to be treated are separated downward, and the vaporized components are separated upward. processing method.