JPH0460058B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for producing a raw material used in glass production from blast furnace slag. [Prior Art] Conventionally, it has been known to use blast furnace slag as a raw material for glass, and for example, there are the following methods. 1 A method in which the molten slag discharged from the furnace is poured into a pit, etc., where it is naturally cooled and solidified, and at this time, the impurities are allowed to settle, and only the upper slag with fewer impurities is taken out and crushed, and then passed through a magnetic separator to remove the iron content ( Special Publication No. 52-21003). 2 A method of injecting water into molten slag and using it as granulated slag, or removing iron by magnetic separation. 3 A method in which the molten slag discharged from the blast furnace is passed through a molten iron separation tank installed in the middle of the slag gutter, where the iron content is separated and the slag still in a molten state is pulverized (Japanese Patent Application Laid-Open No. 54-124013 issue). etc. [Problems to be Solved by the Invention] However, the conventional method as described above has the following drawbacks. For example, in method 1), since the blast furnace slag is naturally slowly cooled slag, sufficient crushing operations are required to obtain a constant particle size, which consumes excessive crushing energy and also When blast furnace slag is used as iron, the iron content, which is considered extremely harmful, is not sufficiently removed by sedimentation, and the solidified slag still contains Fe ₂ O ₃ on average.
It contains about 1.5% of iron, and even if iron is removed by magnetic separation, the content is only reduced to about 0.8%, so it cannot be said to be satisfactory as a raw material for glass. In addition, method 2) does not require pulverization, but as it is, it contains a large amount of molten iron, and iron removal by magnetic separation cannot sufficiently remove the iron. moreover,
Slag usually contains about 4 ppm of corundum (Al ₂ O ₃ ), a refractory used in blast furnaces, which cannot be removed by magnetic separation. Therefore, when used as a raw material for glass, corundum has a high melting point (melting point
(2015℃), it is not completely melted and exists in the form of small particles, causing defects in the glass. In addition, in method 3), even though the corundum of the refractory in the blast furnace settles and is separated with iron in the process of separating molten iron, the slag passes through the refractory troughs until the next process to form granulated slag. Because it is carried
Corundum, which is a refractory mixed here, remains in the granulated slag, and is not preferable as a raw material for glass as described above. The present invention solves these conventional problems and provides a method for obtaining an excellent glass raw material from blast furnace slag by reliably removing not only iron and other heavy metals but also corundum. [Means for Solving the Problems] That is, the present invention injects pressure water into molten blast furnace slag to form granulated slag, and then applies gravity beneficiation to eliminate iron and other harmful impurities as raw materials for glass. This is a method for producing glass raw material from blast furnace slag, which is characterized by removing high melting point compounds. In the present invention, the specific gravity beneficiation means include dry type,
Any type of wet type gravity beneficiation equipment can be applied. Furthermore, if necessary, a step of performing magnetic separation may be added before or after application of the specific gravity separation means, and in this case, iron content can be removed even more reliably. The present invention will be further clarified with reference to Examples below. Example 1 Pressure water was injected into the molten slag flow falling from the blast furnace slag to refine the particles and rapidly cool the resulting granulated slag, which was then classified by approximately 20 meters. Specific gravity separation was performed using a Sogyosha model MH-551). The beneficiation conditions are as follows. Wind speed: 0.7 to 1.3 m/sec Frequency: 600 rpm Amplitude: 5 mm Front-to-back angle: 4° Right-to-left angle: 1.5° The sample flows in the direction of the arrow as shown in Figure 1 and is collected at the bottom, containing substances harmful to glass raw materials such as iron minerals and corundum. is recovered as T, and that which can be used as glass raw material is recovered as C. The Fe ₂ O ₃ grade and amount of corundum of the recovered glass raw material C were as shown in Table 1. From this result, the effect of reducing Fe ₂ O ₃ and removing corundum was confirmed. In addition, since the amount of corundum has a specific gravity of 4.0 to 4.1 g/cm ³ , two types of heavy liquids (specific gravity 3.23 g/cm ³ and 4.5 g/cm ³ ) are used.
It was determined by separating. Example 2 The strength of the magnetic field was
After performing magnetic beneficiation at 5000 Gauss, gravity beneficiation was performed using a dry gravity separator under the same conditions as in Example 1. The results are shown in Table-1. Example 3 After classifying granulated slag with 20 meshes, Example 1
Gravity beneficiation is carried out using a dry type gravity separator under the same conditions as
The obtained material was further subjected to magnetic beneficiation with a magnetic field strength of 5000 Gauss. The results are shown in Table-1. Comparative Example 1 Approximately 20 tons of molten slag was poured into an approximately 7 m ³ pit with a depth of 1.2 m x 1.2 m x 1.4 m, and was naturally cooled and solidified for 8 days. After solidification, the upper layer up to about 1 m below the surface layer was excavated, crushed using a crusher, and iron content was removed using a magnetic separator with a magnetic field strength of 5000 Gauss. The results are shown in Table-1. Comparative Example 2 Water was injected into molten slag to obtain granulated slag, and then iron was removed using a magnetic separator with a magnetic field strength of 5000 Gauss. The results are shown in Table-1. Comparative Example 3 Molten slag was remelted at approximately 1500℃ in a 200ml crucible, then taken out of the furnace and tilted using the tilting method.
Only the upper layer of the molten slag was pulverized and recovered. The results are shown in Table-1.

【table】

〔Effect of the invention〕

As described above, according to the method of the present invention, it is possible to efficiently remove iron as a glass raw material from blast furnace slag, as well as harmful contents, especially corundum, which could not be removed conventionally, from blast furnace slag. Above all, it is extremely beneficial.

[Brief explanation of the drawing]

The drawing is an explanatory diagram showing an overview of dry specific gravity beneficiation.

Claims (1)

[Claims] 1. After injecting pressurized water into molten blast furnace slag to form granulated slag, a specific gravity beneficiation method is applied to remove high melting point compounds, which are harmful impurities as other glass raw materials, along with iron. A method for producing glass raw material from blast furnace slag, which comprises removing blast furnace slag. 2. The method according to claim 1, wherein a magnetic separation operation is performed before or after the gravity beneficiation treatment.