52.5-grade slag portland cement and preparation method thereof

Abstract

The invention relates to a preparation method of 52.5-grade slag portland cement by taking industrial solid wastes as a raw material, and belongs to the fields of solid waste comprehensive utilization and building materials. The invention discloses a preparation method of the 52.5-grade slag portland cement by superfine slag micro-powder with the specific surface area of not less than 600 m<2> / kgand high-grade semi-hydrated desulfurized gypsum. During preparation, the proportions of the superfine slag micro-powder and the high-grade semi-hydrated desulfurized gypsum are not less than 30% by mass, the proportion of the Portland cement (P.II) is not more than 70%, and the content of SO3 in the prepared 52.5-grade slag portland cement is not more than 4.0%. The preparation process adopts a mixing method of a machinery and airflow. The 52.5-grade slag portland cement, provided by the invention, has low hydration heat, so that the service life of the concrete is prolonged; in comparison with the other slag cement, the cement has remarkable early strength advantage, the compressive strength (MPa) is not less than 28 in 3 days, and the compressive strength is not less than 55 in 28 days, the rupture strength (MPa) is not less than 6 in 3 days, and the rupture strength is not less than 8 in 28 days. According to the invention, the slag is doped in a large amount, and zero emission ofthe slag is realized.

Description

technical field [0001] The invention belongs to the field of solid waste comprehensive utilization and building materials, and relates to a 52.5-grade steel slag portland cement and a preparation method thereof. Background technique [0002] With the development of the national economy, my country's steel production has increased year by year, and electricity consumption has also increased year by year, and the industrial solid waste (steel slag, desulfurized gypsum, etc.) discharged thereupon has also increased year by year. It is reported that the annual discharge of steel slag in my country has reached more than 80 million tons in 2011, but the utilization rate is less than or equal to 30%. How to increase the added value of the reuse of steel slag tailings and consume industrial solid waste in a large amount, and reduce the consumption of resources and energy while my country's economic development is a major issue for scientists and technicians in the field of solid was...

AI Technical Summary

Problems solved by technology

[0004] 1. The specific surface area ≥ 600m has not been seen yet 2 Relevant reports on compounding ultra-fine steel slag micropowder, high-grade semi-hydrated gypsum and 52.5 grade Portland cement into 52.5 grade steel slag portland cement

[0005] 2. There is no relevant report (by mass) that more than 30% of steel slag powder, desulfurized gypsum and general-purpose Portland cement can be compounded to make 52.5 grade steel slag Portland cement

[0007] 4. In the reported steel slag cement production process, it has not been seen that the flue gas desulfurization gypsum of coal-fired power plants is first calcined to make high-grade semi-hydrated desulfurization gypsum (β-CaSO 4 1 / 2H 2 (O≥85%), then use it as a steel slag cement component and other steel slag cement components to compound the relevant technical reports

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