Preparation method of superfine slag powder admixture

Abstract

The invention discloses a preparation method of a superfine slag powder admixture and relates to superfine slag powder. The preparation method of the superfine slag powder admixture can overcome disadvantages of the existing independent powder milling process. A dryer is adopted to dry slag; water content of the dried slag is controlled within 0.5-1.0%; a flap valve is arranged at a feed port of the dryer; the front part and the rear part of the dryer are sealed by labyrinth seal rings; a barrel of the dryer is provided with a thermal insulation layer; raising plates of the dryer are L-shaped and are centripetally and uniformly distributed; the number of the raising plates is 10-16 generally; a de-ironing separator is adopted to remove iron impurities from the dried slag; the slag is then fed into a ball mill for powder milling; and the superfine slag powder admixture is obtained.

Description

technical field [0001] The invention relates to a slag micropowder, in particular to a method for preparing a slag micropowder admixture for cement. Background technique [0002] Slag is a kind of industrial solid waste. It is the waste slag discharged during the blast furnace ironmaking process. The output varies with the smelting technology and the ore grade. It is generally 25% to 90% of the pig iron output. According to this, the annual output of slag in my country is estimated at About 60 million tons, slag is mainly used as cement mixing material, slag fine powder can not only produce high-quality slag cement, but also can be widely used in concrete mixing plants, construction products and concrete engineering fields, can give full play to the activity of cement and avoid over-grinding phenomenon . However, because the slag is fragile and difficult to grind, in the existing slag powder preparation process, the slag is generally processed together as a mixed material, an...

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Problems solved by technology

[0004] However, the existing separate grinding process is still difficult to meet the standard requirements such as activity index, because there are the following main shortcomings in the control of equipment and process conditions:

[0005] 1. The form of lifting plates inside the dryer is single, the layout is unreasonable, and the number is small, so a wind tunnel is formed, and it is difficult to form a uniform material curtain

[0006] 2. There is no ventilation device in the drying storage tank; this cannot effectively reduce the temperature of the slag, and the slag is not easy to grind, which affects the activity index of the slag powder

[0007] 3. The moisture content in the mill is high, which will easily lead to frequent full grinding and dull grinding, which will affect the processing quality (such as the activity of the finished product)

[0008] 4. The barrel of the dryer has no heat insulation, and the heat loss is large, which affects the drying effect of the dryer, thus affecting the activity of the finished product

[0009] 5. The traditional ball mill is not equipped with a spiral activation liner, so that the material flow rate is too fast, the grinding time is short, the specific surface area is difficult to reach more than 400, and the quality is unstable

Moreover, the grating grate at the discharge port is wider, and it is easy to leak larger broken forgings.

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