Pyrite is fired in many countries

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Pyrite is the name of a group of minerals that are compounds of metals from the group of tin, nickel, iron, cob alt, platinum. Compounds can be either sulphurous and arsenic, or antimony or selenium.

Pyrite roasting assumes that the raw material has a light color, metallic luster, hardness from 3 to 7. Iron or sulfur pyrite (FeS2 formula), also known as pyrite, is a valuable technical raw material from which sulfur dioxide is obtained (chamber production). In appearance, the mineral is a mass of small, regular-shaped yellowish-gray crystals with a hardness of 6-6.5. The composition of pure pyrites includes about 47 percent iron and about 53 percent sulfur.

Roasting pyrite is accompanied by a series of chemical reactions, of which the first gives the decomposition of the mineral into iron sulfide and sulfur in a vapor state (at a temperature of about 500 C). Then the sulfur vapor burns, giving sulfur dioxide, and iron sulfide gives oxide or nitrous oxide. Moreover, the sulfide burns out incompletely, forming"Cinder", which may include fayalite and other substances, depending on the impurities in the feedstock.

Roasting pyrites can produce some SO3 mixed with SO2 in the gas phase. This substance acts on the equipment in a corrosive way, therefore, in order to reduce SO3, the gas temperature at the outlet of the furnace equipment should be about 850C, and then quickly decrease to 400C.

Roasting pyrites is practiced in many countries, because this element is one of the most widely used. In Russia, this mineral is mined at the Soymenskaya dacha, the Kalitvinskoye deposit, near Kushva, at the Bogoslovsky factories, in the Caucasus, in the Ryazan and Smolensk regions, and in other places. Spanish deposits are especially famous abroad (especially Aguas Tenidas, where the material does not contain copper, but has a high sulfur content), in addition, developments in the USA, France, Norway, and Sweden are exploited. Arsenic varieties of this substance are often mixed with sulfur pyrite in nature, which gives a very harmful impurity during production in chambers. Therefore, manufacturers try to use pure raw materials. For example, Russian plants in St. Petersburg are powered by Swedish pyrites.

Roasting of iron pyrites (as well as sulfur pyrites) is carried out in furnaces, where raw materials are fed through a screw or nozzle. Then it is mixed with the mass of solid material that is already in the unit (in a fluidized bed on a grate, under which air is supplied from below), after whichchemical reactions occur, giving gas (discharged) and cinder (partially poured through special pipes). Also, excess heat is removed from the oven with the help of water cooling elements.

Roasting pyrites will be successful if the contact surface of raw material with air is large enough. Therefore, the mineral is often processed in a dusty state (in appropriate furnaces), when the particle size is so small that oxygen freely penetrates into the mass of the substance. In addition, the temperature regime is important, because. minerals in this class are often sintered at temperatures above 900 C. To solve this problem, processing in the form of a dust-air mixture is also used, which allows the raw materials to be burned at temperatures up to 1000 C, which increases production efficiency.