TW201429920A - Carbonless alumina-magnesia unburned brick - Google Patents

Abstract

A carbonless alumina-magnesia unburned brick comprises, based on 100 wt% of the total weight, 15-35 wt% of brown corundum, 55-75 wt% of white corundum, 2-5 wt% of magnesite, 1-3 wt% of silica sand, 0.5-1.5 wt% of waste pulp powder, and 1-3 wt% of magnesium chloride. This invention, by using brown corundum and white corundum as the main ingredients, with the addition of some magnesite and silica sand and using magnesium chloride and waste pulp powder as binders, produces brick blanks containing alumina-magnesia spinel. In addition, it does not require large working machines for mixing and possesses excellent anti-corrosion capability, and the preheating time is short, thereby saving the operation time for manufacturing and steelmaking.

Description

Carbon-free aluminum-magnesium without burning brick

The invention relates to a non-burned brick, in particular to a carbon-free aluminum-magnesium unfired brick.

In order to extend the service life of steelmaking operations, the existing steel drum linings used in existing steel plants are usually made of high-aluminum cement combined with aluminum-magnesium castables. The high alumina cement combined with the aluminum-magnesium castable is a brown fused alumina containing 25% by weight, a white corundum of 65.7% by weight, and a weight percentage of 6%, based on 100% by weight of the high alumina cement combined with the aluminum-magnesium castable. The magnesite, 0.3% by weight of cerium oxide sand, 3% by weight of high alumina cement, and 0.03% by weight of dispersant.

However, when high-aluminum cement combined with aluminum-magnesium castables are cast into lining, it is necessary to use large-scale construction equipment (such as mixing with a mixer) and the time required for curing after pouring, and the water content of the castable after the pouring is completed. More, so it should be combined with long-term preheating, used to remove water to avoid flaking of the lining, so as not to affect the service life of the steel drum, and the high-aluminum cement combined with the aluminum-magnesium castable lining in the refining electrical In steel, due to the composition of high-aluminum cement, the speed at which the lining is eroded will be intensified, and the service life of the lining will be greatly reduced (from 180 to 160 furnaces). In addition, high aluminum water Mud combined with aluminum-magnesium castables often requires investment in large-scale construction equipment and preheating equipment with better preheating effect, so that the steelmaking operation can be carried out smoothly, but the cost of manufacturing and maintenance is also increased.

Accordingly, it is an object of the present invention to provide a carbon-free aluminum-magnesium non-fired brick that reduces preheating time and does not require large construction equipment.

Therefore, the carbon-free aluminum-magnesium non-fired brick of the present invention comprises: the composition comprises 100% by weight of the total weight percent, brown corundum of 15% to 35% by weight, and 55% to 75% by weight of white corundum, The percentage by weight is from 2% to 5% by weight of magnesia, from 1% to 3% by weight of cerium oxide sand, from 0.5% to 1.5% by weight of waste pulp powder, and from 1% to 3% by weight of magnesium chloride.

The utility model has the advantages that: the brown corundum and the white corundum are used as the substrate, a little magnesia and cerium oxide sand are added, and the magnesium chloride and the waste pulp powder are combined as a binder to produce a brick embryo with aluminum magnesium spinel, and no It requires the agitation of large construction machines and has excellent anti-erosion function, and the preheating time is short, saving the working time on manufacturing and steel making.

A preferred embodiment of the carbon-free aluminum-magnesium non-fired brick of the present invention comprises: the composition comprises 100% by weight of the total weight percent, and the weight percentage is 15% to 35% of brown fused alumina, and the weight percentage is 55% to 75. % white just Jade, 2% to 5% by weight of magnesia, 1% to 3% by weight of cerium oxide sand, 0.5% to 1.5% by weight of waste paper pulp, and 1% to 3% by weight Magnesium chloride.

Specifically, in the preferred embodiment, the average particle diameter of the brown corundum is 5 mm to 15 mm, the average particle diameter of the white corundum is not more than 5 mm, the average particle diameter of the magnesia is not more than 0.3 mm, and the average of the cerium oxide sand The particle size is less than 0.075 mm.

The main components contained in brown fused alumina, white corundum, magnesia, and cerium oxide are further described below. The composition of the brown corundum has more than 95% of aluminum oxide (Al ₂ O ₃ ), and the total weight percentage of white corundum is 100%, and the composition of the white corundum is 100% by weight of the total weight of the brown corundum. It has 98% or more of aluminum oxide (Al ₂ O ₃ ). The composition of the magnesia has 95% or more of magnesium oxide (MgO) based on 100% by weight of the total weight of the magnesia. The composition of the cerium oxide sand has 98% or more of cerium oxide sand (SiO ₂ ) based on 100% by weight of the total weight of cerium oxide sand.

Table 1 below is a comparison of the experimental examples in this example with the conventional aluminum-magnesium castables in combination with high alumina cement.

The preferred formulation of the carbon-free aluminum-magnesium non-fired brick of the present invention is shown in Table 1. Of course, Table 1 lists only one of the formulation parameters of the preferred embodiment, and is not limited to the parameters in Table 1. Moreover, after testing, the carbon-free aluminum-magnesium non-fired brick prepared by the above preferred formulation has excellent physical properties: body density (g/cm ³ ) is not less than 3.2; surface porosity (%) is not more than 14.0; room temperature The crushing strength (MPa) is not less than 20.0.

It can be seen from Table 2 below that in the refining of electric steel, the average service life of the lining made of the carbon-free aluminum-magnesium non-fired brick of the present invention is higher than that of the existing high-aluminum cement combined with the aluminum-magnesium castable, and since The carbon aluminum-magnesium non-fired brick has less water content, so it is obviously superior to the existing high-aluminum cement combined with aluminum-magnesium castable in the preheating time, and does not need to be used for health maintenance in manufacturing, so it is relatively more cost-effective to manufacture. At the same time, magnesium chloride and waste paper pulp powder can be used as a binder to produce aluminum-magnesium spinel, which has excellent function for resisting slag erosion, so that in the environment of slag, slag penetrates into the permeation layer of the carbon-free aluminum-magnesium unfired brick. It is 1mm, which is good for restraining the structural thermal shock spalling. At the same time, the erosion index is about one-tenth of that of high-alumina cement combined with aluminum-magnesium castable, which makes the embodiment improve in service life and time.

In summary, compared with the existing high-aluminum cement combined with aluminum-magnesium castable formulation, the present invention produces a preheating time of about one-third with a new formula, does not require large construction equipment, has a long service life, and does not need to be carried out. The health-free carbon-free aluminum-magnesium does not burn bricks, so the cost in manufacturing and furnace repair operations can be reduced, so that the object of the present invention can be achieved.

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the patent application scope and patent specification content of the present invention, All remain within the scope of the invention patent.

Claims (3)

A carbon-free aluminum-magnesium unfired brick comprising: a composition comprising 100% to 35% by weight of a total of 100% by weight of brown fused alumina, 55% to 75% by weight of white fused alumina, by weight It is 2% to 5% magnesia, 1% to 3% by weight of cerium oxide sand, 0.5% to 1.5% by weight of waste paper pulp, and 1% to 3% by weight of magnesium chloride. The carbon-free aluminum-magnesium non-fired brick according to claim 1, wherein the average particle diameter of the brown corundum is 5 mm to 15 mm, the average particle diameter of the white corundum is not more than 5 mm, and the average particle diameter of the magnesia is not more than 0.3 mm, and oxidation is performed. The average particle size of the cerium is less than 0.075 mm. The carbon-free aluminum-magnesia non-fired brick according to claim 1 or 2, wherein the total weight percentage is 100%, the weight percentage is 25% brown fused alumina, the weight percentage is 66.5% white corundum, and the weight percentage is 3.5% magnesia, 1.5% by weight cerium oxide sand, 1% by weight waste paper pulp powder, and 2% by weight magnesium chloride.