JPS6240326A - Manufacture of binder - Google Patents

Abstract

PURPOSE:To manufacture inexpensive sintering binder, by making blast furnace granulated slag, ferronickel slag, steel making slag rapidly cooling treated from molten state and stimulating agent such as CaSO4.2H2O, CaO, Ca(OH)2. CONSTITUTION:Sintering binder is composed of blast furnace granulated slag, ferronickel slag, steel making slag rapidly cooling treated from molten state, and stimulating agent composed of at least >=one kind among CaSO4.2H2O, CaO, Ca(OH)2, CaCl2, NaOH, Na2CO3, is inexpensive and superior in effect for sintered product. Sometimes, modifier composed of a least >=one kind among rock or mineral or the weathered material of silicate quantity, slag, glass scrap, molding sand waste, coal ash, waste brick, red mud, volcano eruptions, blast furnace slag, desiliconization slag, iron oxide is added to the steel making slag during the molten state to react then, then the slag is rapidly cooled and used, or cement can also be used instead of this.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a binder used in producing sintered ore which is charged into a blast furnace.

<Prior art> The currently used sintering method involves mixing iron ore powder of approximately 10 mm or less with coke and an appropriate amount of limestone powder, charging the mixture into a sintering pallet, and then igniting the coke in the surface layer. In this method, coke is combusted while air is sucked downward, and the ore powder is sintered using the combustion heat.

As described above, since sintering progresses through the combustion of coke, the degree of permeability of the sintered layer, which determines the degree of air supply to the sintered layer, is an important operational factor. In order to improve this air permeability, a number of measures have been taken, such as improving granulation conditions and extending granulation time, but the binder used is also a major factor. Binders conventionally used in this type of sintering are quicklime and quick-setting cement components.

<Problems to be Solved by the Invention> Although the quicklime and quick-setting cement components used as the sintering binder described above are effective, they are expensive, resulting in a problem of high costs.

The present inventor previously made an invention using steelmaking slag as an inexpensive binder for sintering, and also made an invention using ferronickel slag and IS slag in Japanese Patent Application No. 1984-84148. Although the blast furnace water slag is used as an admixture for blast furnace cement, it has not yet been completely digested, and effective utilization is desired.

<Means for Solving the Problems> The present invention attempts to use inexpensive blast furnace water slag and ferronickel slag in place of quicklime and quick-setting cement, which have been conventionally used as binders for sintering. The gist is blast furnace water slag, ferronyl slag, and steelmaking slag CaSO4.21120, which is rapidly cooled from a molten state. Cab
, Ca(Off)2. CaCl2. Na0)1
．． This is a sintering binder consisting of a mixed powder with a stimulant consisting of at least one type of Na2CO3, and while the N steel slag used in this case is in a molten state, silicate rocks or minerals or their weathered products, calamic , glass scraps, foundry waste sand 1 coal ash, waste bricks, red mud, volcanic ejecta,
It may be used in the form of a product that is rapidly cooled after adding a modifying material consisting of at least one of blast furnace slag, desiliconization slag, and m-ferric iron and causing a melting reaction.Furthermore, cement may be used instead of steelmaking slag. There are some things.

Adding modifying materials such as silicate rocks to molten steelmaking slag in this way improves the mineral composition of steelmaking slag.
From α′ to β-2CaO・5i02 main body, 2CaO-3
Mainly composed of i02~2CaO・MgO・2SiO2 to eliminate collapse-expansion properties, reduce melting point and viscosity to make handling easier, and improve quenching rate during quenching to sharpen a large amount of glass. The method of addition is not particularly limited, and an appropriate method is adopted depending on the work process or the situation at the work site.

<Examples and effects> The present invention will be described in detail below with reference to Examples.

Chemical analysis values of the samples used in this example are shown in Table 1 below.

In addition, quicklime, slaked lime, NaOH, Na2CO3, Ca
Reagent grade was used for C1□, etc., and commercially available Portland cement was used as the cement. Furthermore, a commercially available blast furnace water slag was used.

The reforming reduction stage slag and reforming converter slag in Table 1 above refer to the reduction stage slag and converter slag, respectively.
This is slag to which about 10% by weight of the above-mentioned modifier is added.

Blast furnace water slag, ferronyl slag, steelmaking water slag, stimulant (C
After adding ab, Ca(Off)2), it was ground in a test ball mill to a Blaine value of 3100 ± 50 Cffl”/g.
Or blast furnace water slag, fu, o2 full slag stimulant (Cab,
After adding Ca(O)I)2), grind it to a Blaine value of 3100±50Cm2/g with a test ball mill, add commercially available Portland cement, or mix Cab in the stimulant.
Na0HCaC12, Na2 other than Ca(011)2
When adding CO, etc., dissolve it in kneading water and use it.
Table 2 shows the results of adding the mixture to water, kneading it, putting it in a plastic bag, and examining the hardening status.

Next, Table 4 shows the results of sintering using the binder of the present invention under the mixing ratio and conditions shown in Table 3. In this Table 4, "Test NaJ" is the test number shown in Table 2 above.
is the same as

For comparison, Table 4 also shows the results when quicklime was used as a binder and when no binder was used as a conventional example. In addition, the amount of binder was 1ffi amount % in both the case of the present invention and the case of the conventional example.

Table 3 Table 4 As is clear from Table 4 above, the sintered products using the binder of the present invention are superior to those without the binder in both productivity9 yield and strength. It can be seen that there is no inferiority compared to the case of using quicklime.

<Effects of the Invention> As described above, according to the present invention, inexpensive blast furnace water slag,
By using ferroninol slag, steelmaking slag, cement, and a small amount of stimulant, it can be used as a sintering binder that can replace expensive quicklime and quick-setting cement.
In that case, the effect on the sintered product is equivalent to that of conventional expensive quicklime. Furthermore, it is beneficial from the perspective of recycling blast furnace slag and steelmaking slag, which are byproducts of the steel industry. Also the first
As shown in the table, ferronisol slag contains a large amount of MgO, and since this MgO also has a desulfurization effect, it also has the effect of improving the quality of the sintered product.

Claims (3)

[Claims] (1) Blast furnace water slag, ferronickel slag, steelmaking slag that has been rapidly cooled from the molten state, and CaSO_4・2H_
2O, CaOCa(OH)_2, CaCl_2, NaO
A method for producing a sintering binder comprising a mixed powder with a stimulant consisting of at least one of H, Na_2CO_3. (2) Blast furnace water slag, ferronickel slag, molten steelmaking slag, silicate rocks or minerals or their weathered products, karami, glass scraps, foundry waste sand, coal ash, waste bricks, red mud, volcanic ejecta. , blast furnace slag, desiliconization slag, and iron oxide, a product obtained by adding a modifying material consisting of at least one of iron oxide, causing a melting reaction, and then quenching, and CaSO_4
・2H_2O, CaO, Ca(OH)_2・CaCl_
2. A method for producing a sintering binder comprising a mixed powder with a stimulant consisting of at least one of NaOH and Na_2CO_3. (3) Blast furnace water slag, ferronickel slag, cement, CaSO_4・2H_2O, CaO, Ca(OH)
_2, a method for producing a sintering binder comprising a mixed powder with a stimulant consisting of at least one of CaCl_2, NaOH, and Na_2CO_3.