Chromium is used to make stainless steel, auto parts, tools, tapes and videotapes. Chromium plating on metal can prevent rust, firm and beautiful. Chromium can be used to make stainless steel. The color of red and emerald also comes from chromium. As the most important metal in modern science and technology, Inconel steel fused with different percentages has a variety and incredible variety. Because of its brittleness, chromium alloy is still being studied as a metal material. Chromium is mainly used in the form of ferroalloy (such as ferrochromium) to produce stainless steel and various alloy steels. Chromium is used as an additive for aluminum alloy, cobalt alloy, titanium alloy, superalloy and resistance heating alloy. Chromium oxide is used as a light and heat-resistant coating, as well as an abrasive, a colorant for glass and ceramics, and a catalyst for chemical synthesis. Basic chromium sulfate (trivalent chromium salt) is used as tanning agent for leather. Chrome alum and dichromate are used as mordant, impregnant and various pigments for fabric dyeing. Chromium plating and chromizing can make steel, copper, aluminum and other metals form a corrosion-resistant surface, which is bright and beautiful. It is widely used in furniture, automobile, construction and other industries. In addition, chrome ore is also widely used to make refractory materials. Fodamon engineers will analyze how to beneficiate chromium ore for you.
Because chromium is the most used metal and ranks first in the “strategic metals”. Nowadays, countries with chromium ore resources or countries with lack of resources are stepping up the research on chromium ore dressing, and their separation methods are as follows;
(1) Gravity separation: such as jig, shaking table, spiral chute, heavy medium cyclone, etc.
(2) Magnetoelectric separator: including high-strength field magnetic separator and high-voltage electric separator.
(3) Flotation and flocculation flotation.
(4) Combined selection: such as re selection and electric selection.
(5) Chemical beneficiation: treatment of very fine refractory chromium poor ore.
Among the above chromium ore dressing methods, gravity separation method is mainly used in production, and shaking table and jig are often used for separation. Sometimes the gravity concentrate is re selected by weak magnetic separation or strong magnetic separation to further improve the grade of chromium concentrate and chromium iron ratio.
Chromium spinel is an ore with high iron content or dense symbiosis with magnetite. In the concentrate obtained after beneficiation, the chromium grade and chromium iron ratio are low. It can be considered as an ingredient for pyrometallurgical production of ferrochromium or treated by hydrometallurgy. For example, sodium dichromate method, chromium hydroxide method, reduction corrosion method, chlorination roasting acid leaching or electrolysis method, etc. Hydrometallurgical treatment of low-grade ferrochrome concentrate has been practiced.
Platinum group (platinum, palladium, iridium, osmium, nail and rhodium), cobalt, titanium, vanadium, nickel and other elements are often associated in chromium deposits. Comprehensive recovery shall be considered when platinum content is greater than 0.2-0.4g/t, cobalt content is greater than 0.02% and nickel content is greater than 0.2%. The associated platinum group elements in ferrochrome ore, such as sulfide, arsenide or sulfur arsenide, can be recovered by flotation. Olivine and serpentine in the ore can be comprehensively recovered for the production of refractory, calcium magnesium phosphate fertilizer or diabase cast stone. In the shallow part of ultrabasic rock mass, there are sometimes amorphous magnesite caused by weathering and leaching, which is also a good raw material for refractory.
Recently, China has made some progress in the beneficiation research of chromium ore. for example, relevant units adopt stage grinding and spiral chute separation for difficult beneficiation in a certain area, so that the grade of chromium concentrate is increased from 22.4% of raw ore to 35% and the recovery rate is 80.18%. For easy beneficiation of poor chromium ore, the combined separation process of jigging and shaking table is adopted, and the grade of chromium concentrate is increased from 19% of raw ore to 40%.
As we all know, in natural chromium ore, low silicon chromium ore with SiO2 content less than 2% almost does not exist, and can be obtained only through beneficiation and purification. Therefore, it is of great significance to study the beneficiation and silicon reduction process of refractory chromium ore for the development of magnesium, aluminum and chromium refractories.