Method for preparing high-ferric Alite-calcium barium sulphoaluminate cement by using red mud and barium mud

Abstract

The invention discloses a method for preparing high-ferric Alite-calcium barium sulphoaluminate cement by using red mud and barium mud. The mineral phases are as follows in percentage by weight: 5-8% of C(4-x)BxA3S, 15-19% of C2S, 30-45% of C3S, 25-45% of C4AF and 4-8% of C3A; the raw materials are as follows in percentage by weight: 10-20% of clay, 8-30% of red mud, 55-65% of limestones, 3-5% of gypsum, 0.3-0.5% of barium mud, 0-2% of bauxite and 0.4-1% of fluorite. The method comprises the following steps: crushing and homogenizing the raw materials and drying and polishing; preparing a round cake-shaped test sample which is 5cm in radius and 2cm in thickness, and calcining and cooling; and (6) crushing, and doping 8-12% of gypsum or dihydrate gypsum based on the total mass of the material, wherein the grinding fineness is 350m<2>/kg-450m<2>/kg or residue on sieve is 5% by a 200mesh sieve. The high-ferric Alite-calcium barium sulphoaluminate cement disclosed by the invention has the characteristics of low sintering temperature and small volume shrinkage, low cost and durability and the like as high-ferric or high-ferric aluminum industrial wastes and barium-containing industrial waste residues are used as raw materials.

Description

technical field [0001] The invention belongs to the technical field of cement preparation, in particular to the preparation of barium calcium sulfoaluminate mineral (CBA) by using red mud and barium mud as raw materials. ), Alite (C 3 S) and tetracalcium aluminoferrite (C 4 AF) Mineral-composite high-iron Alite-barium calcium sulfoaluminate cement. Background technique [0002] The degree of social development is increasing day by day, and the requirements for my country's infrastructure construction and engineering quality are constantly improving. The disadvantages and shortcomings of traditional Portland cement are becoming more and more obvious, mainly reflected in the consumption of a large amount of high-quality limestone resources, high firing temperature, and coal resources. The loss is huge, bringing the greenhouse gas CO 2 and harmful gas SO x , NO x Emissions increased sharply, which aggravated the environmental load, and the design content of tricalcium sili...

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Problems solved by technology

Previous scholars have studied that the content of iron phase in traditional Portland cement accounts for 8% to 12%, mainly playing the role of flux in the firing process of cement, improving the burnability of raw materials, and whether there is a good effect on iron phase. There are doubts about the gelling property, but with the emergence of ferro-aluminate cement and high-iron cement with excellent performance and energy saving, its firing temperature is generally around 1300°C, which is about 150°C lower than that of traditional Portland cement, and higher than that of traditional Portland cement. Iron-phase minerals with low enthalpy of formation are the dominant minerals in cement varieties, and more and more attention has been paid to them. Barium calcium sulfoaluminate mineral is a rapid hardening and early strength mineral developed by Chang Jun and other scholars in recent years. It has certain micro-expansion characteristics, and the firing temperature is about 1350°C. The present invention uses C 4 AF and CBA Composite, introduced into the Portland cement cement system, reducing the content of tricalcium silicate, so that the mineral phase formation temperature in the gelling system is formed at about 1300 ° C, saving energy, reducing costs, and solving the problem of traditional silicate The disadvantages of high pollution, high energy consumption, and shrinkage and cracking of cement in the late stage of hydration in the cement industry. Since barium calcium sulfoaluminate is an early-strength mineral, compensation due to C 4 AF content replaces early strength mineral C 3 The content of S leads to the disadvantage of low early strength of cement. At the same time, the production of high-iron Alite-barium calcium sulfoaluminate cement can use ferrite with much lower alumina content, industrial waste slag containing high-iron or high-iron-aluminum and barium-containing The industrial waste residue has a wider source of raw materials, which further reduces the cost and provides an effective way for the treatment of industrial waste residue

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