Magnesite Activation Roasting Gravity Separation Silicon Removal Process

Abstract

The invention relates to a magnesite activated-roasting, reselecting and silica-removing process. The magnesite activated-roasting, reselecting and silica-removing process is characterized by comprising the following steps that lean magnesite is crushed and screened to obtain raw magnesite having the granularity of 0-30 mm; 5%-10% of fine magnesium oxide powder is added into the raw magnesite, 0.5%-1% of magnesium chloride and 7%-12% of water are added, even stirring is performed, mechanical pressing is performed to form magnesite blanks, the blanks are put in a drying furnace for drying and dehydration; then, the blanks are put in a shaft kiln of 900-1100 DEG C, and activated roasting is performed for 1.5-2.5 hours; the roasted magnesite blanks are fed into a mill to be stirred and ground; air classification is conducted on the ground products, the products greater than 500 mesh are impurities, the products smaller than 500 mesh are directly fed into a cyclone dust collector for gas-solid separation, and a magnesium oxide product having the obtained magnesium oxide content of 96.6% or above and the SiO2 content lower than 0.32% is obtained. Compared with the prior art, the magnesite activated-roasting, reselecting and silica-removing process has the advantages of being simple in technological process, good in raw ore adaptability, suitable for industrial production, low in cost and low in investment.

Description

technical field [0001] The invention belongs to the technical field of magnesite beneficiation, and in particular relates to a magnesite activation, roasting, gravity separation and silicon removal process for separating lean magnesite ore. Background technique [0002] Our country is rich in magnesite resources, but there are not many rich ore resources. The gangue minerals contained in magnesite are mainly SiO 2 , other impurities such as CaCO 3 , Fe 2 o 3 , Al 2 o 3 The equivalent content is relatively small. According to the "Compilation of Refractory Materials Standards", magnesite is based on the MgO and SiO in the ore 2 The content of the special grade ore is classified, the content of MgO in super ore is > 47%, and the content of SiO 2 content <0.3%; primary ore MgO content> 46.5%, SiO 2 Content<0.6%, secondary ore MgO content>46%, SiO 2 content <1.5%; tertiary ore MgO content> 45%, SiO 2 Content<2.5%; MgO content<45%, SiO 2 Mag...

AI Technical Summary

Problems solved by technology

Application No. 200610134894.9 discloses the invention patent "Magnesite Thermal Separation Process", which provides roasting of lean magnesite ore, and then self-crushing and screening operations to remove silica, calcium oxide, partial iron oxide and alumina and other inclusion minerals, so that the MgO content of light-burned magnesium powder can reach more than 96%, and the purification effect on lean magnesite ore is obvious; however, it is not suitable for industrial production to use sieving operations to classify fine-grained ore powder.

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