High magnesium slag doped cement

Abstract

The invention discloses high magnesium slag doped cement. The raw materials of the cement comprise the following main minerals in percentage by weight: 65-82% of limestone, 1-20% of magnesium slag, 5.5-9.4% of sandstone and 4-8% of coal gangue, wherein the magnesium slag comprises the following main chemical components: less than or equal to 55% and greater than or equal to 50% of CaO, greater than or equal to 20% and less than or equal to 30% of SiO2, greater than or equal to 8% and less than or equal to 12% of MgO, greater than or equal to 4% and less than or equal to 6% of Fe2O3, and greater than 0% and less than or equal to 2% of Al2O3. The cement is prepared by sequentially passing blended raw materials through a raw material drying mill, a raw material homogenizing silo, a decomposing furnace and a rotary kiln, blending the prepared clinker with coal ash, desulfurization gypsum and slag, and feeding the above materials into a cement mill. As high as 20% of magnesium slag is doped into the high magnesium slag doped cement, so that not only is the service life of a limestone mine prolonged, but also industrial wastes such as greatly piled magnesium slag are effectively utilized, the burnability of the clinker is also improved, the content of f-CaO in the clinker is reduced, and the national standard is met.

Description

technical field [0001] The invention relates to a building material, in particular to a cement with high magnesium slag content. Background technique [0002] Cement is an indispensable engineering basic material in construction projects. With the acceleration of my country's industrialization and urban-rural integration, the demand for cement will increase for a long period of time. It is estimated that around 2015, my country's cement demand will reach 1.9-2.3 billion tons, and the consumption of limestone, the main raw material, will reach 1.16-1.41 billion tons. In addition, limestone is also consumed in metallurgical solvents, building stones, pharmaceutical and chemical production, etc. In the long run, it will pose a threat to the reserves of limestone in our country. Therefore, our country encourages enterprises to use industrial waste slag (such as: smelting slag, coal gangue, fly ash, etc.) 2 、Al 2 o 3 and Fe 2 o 3 , and these ingredients are necessary for cem...

AI Technical Summary

Problems solved by technology

[0004] (1) Magnesium slag itself is powdery, and after water quenching, the moisture entering the factory is about 15%. After entering the mill, the output of the raw material mill will be slightly reduced due to the high comprehensive moisture of the material

[0005] (2) During the process of feeding and transferring magnesium slag, it is easy to adhere to the belt conveying equipment, resulting in poor feeding and blockage

[0006] (3) The proportion of magnesium slag replacing limestone is not high, most of which are less than 12%, and there is no obvious improvement in the situation of massive accumulation of magnesium slag waste and urgent limestone reserves

[0007] (4) When calcining clinker with magnesium slag, it is easy to have adverse effects such as rings and balls in the rotary kiln

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