Recycling method for calcium-free chromium slag sintered building block

Abstract

The invention discloses a recycling method for a calcium-free chromium slag sintered building block. The recycling method is characterized by comprising the following steps of: preparing calcium-free chromium slag and coke powder in a mass percent of (85%-95%:(10%-15%) into mixed materials; uniformly mixing the mixed materials in a primary mixer and adding water to moisten the mixed materials, wherein the mixture of the mixed materials is controlled to 12%-14%; adding the moistened mixed materials to a secondary mixer for pelletizing, wherein the rotation speed of the mixer is 16-18 revolutions / min, and the pelletizing time is 4 minutes to 5 minutes; distributing the obtained pelletized mixed materials to a sintering cup by a material distributor, wherein the material layer is parallel to the cup port, and the thickness of the material layer is 500mm-650mm; and igniting the mixed materials, wherein the ignition temperature is 900 DEG C to 1000 DEG C, and the ignition time is 2.5 minutes to 3.5 minutes. The sintering and air-drafting negative pressure is 9500 Pa to 10000 Pa, the hexavalent chromium of the chromium slag in the mixed materials is reduced to trivalent chromium, i.e., the reducing product of Cr<6+> finally exists in a stable Cr2O3 form, thereby achieving the recycling of the resources.

Description

Technical field: [0001] The invention relates to waste slag treatment technology, in particular to a detoxification and recycling method for solid calcium-free chromium slag. Background technique: [0002] Chromium slag is a solid waste slag produced during the smelting of ferrochrome alloys, and it is the first serious pollution in my country's chemical industry. Inner Mongolia Yellow River Chromium Salt Co., Ltd. has produced a large number of waste products without calcium and chromium slag in recent years. They have been piled up near the factory without treatment, causing great harm to the nearby environment and human health. In order to reduce this kind of pollution and harm, at the same time, the content of Cr and Fe in the slag is relatively high, which has certain smelting value. Therefore, timely detoxification of calcium-free chromium slag and its rational application has become a top priority. [0003] In recent years, the research on the treatment of chromium ...

AI Technical Summary

Problems solved by technology

Using the high temperature of sintering or roasting to make the spherical core form a reducing atmosphere in the spherical shell, the chromium slag can be pretreated, and then enter the blast furnace for thorough treatment of the chromium slag, and the treatment process is complicated.

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