Dense granule magnesia-calcia material and preparation method thereof

Abstract

The invention relates to a dense granule magnesia-calcia material and a preparation method thereof. According to the technical scheme, lightly burnt dolomite is hydrated, filtered and dried and then magnesium-calcium hydroxide powder is obtained; the magnesium-calcium hydroxide powder and an additive are prepared in the mass ratio being 1:(0.002-0.05), subjected to wet grinding, filtered, dried and ground; the magnesium-calcium hydroxide mixture powder obtained through grinding is put into granulation equipment, water accounting for 8-30wt% of the magnesium-calcium hydroxide mixture powder is added under the condition of 1,000-3,000 rpm, and when granules are formed, the granulation equipment is adjusted to run at the speed of 500-1,000 rpm and is stopped after all the magnesium-calcium hydroxide mixture powder is made into magnesium-calcium hydroxide granules; the magnesium-calcium hydroxide granules are put into a heating furnace and kept at the temperature of 1,400-1,800 DEG C for 1-5 h, nitrogen or argon is introduced at the speed of 0.5-5 l / min until the temperature reaches 35-70 DEG C, and the dense granule magnesia-calcia material is obtained. According to the dense granule magnesia-calcia material, the process is simple, the cost is low and the energy consumption is low; the prepared dense granule magnesia-calcia material can be used at a high temperature and has stable high-temperature performance and good hydration resistance.

Description

technical field [0001] The invention belongs to the technical field of refractory materials and high-temperature ceramics. In particular, it relates to a dense granular magnesium-calcium material and a preparation method thereof. Background technique [0002] Magnesium-calcium materials have been successfully used in the metallurgical industry in the last century, and have played a positive role in the technological progress of the metallurgical industry. However, because the products are prone to hydration, their use is subject to certain restrictions. After the 1960s, basic steelmaking converters were rapidly promoted all over the world, and magnesium-calcium materials as basic refractory materials were paid attention to, which led to rapid development. In terms of the production of magnesia-calcium raw materials, it has developed from one-step calcination in a single coke shaft kiln to two-step calcined dolomite clinker, artificially synthesized calcined dolomite clinker...

AI Technical Summary

Problems solved by technology

[0004] It can be seen that the preparation method of the existing magnesium-calcium particles not only has high cost and energy consumption, but also has complex processes

The key is that in the existing technical route, the sintered layer on the surface of the magnesium-calcium body after high-temperature treatment is severely damaged during the crushing process, and a new surface is exposed after the crushing, resulting in the extremely easy hydration of the magnesium-calcium particles. It has brought great difficulties to the reserve of magnesium-calcium raw materials and the production of calcium oxide-based materials