SU128854A1 - The method of obtaining the sulfuric anhydride - Google Patents

Description

The known method of creeping sulfur dioxide by the oxidation of pyrites (pyrite).

The described method provides for the production of 100% sulfuric anhydride. To this end, pyrite (pyrite) is oxidized without access to air — by calcining the mixture of sulphate as well. Pyrite under external heating or by passing heated sulphurous anhydride through a mixture in a fluidized bed.

Fig. 1 is a schematic of the setup for producing pyrite sulphurous anhydride and FeSO4; in fig. 2 shows a setup for the preparation of sulfur dioxide from pyrites and Pe2 (504). To obtain ferrous anhydride by passing the mixture in a fluidized bed, the method is carried out as follows (Scheme 1).

The decomposition of a mixture of pyrite (crushed or flotation pyrites) and FeS04 is carried out in a medium of a heated inert material / furnace 2. In a fluidized bed (1 material is created using a reversible HFg, a preheated heat exchanger 5 using heat from the exhaust gases from apparatus 4. Inert material (quartz sand, pyrite cinder, etc.) before feeding from furnace 3, is ee to the required temperature (900-1000 °) in apparatus 4 by means of flue gases obtained by burning fuel. Inert m The material after part of its heat is returned from the furnace 2 enters the rotating drum (or into the fluidized bed apparatus), where it is cooled somewhat, ii preheating the air going to the fuel, then the material enters the apparatus 4, which can also be performed in as a fluidized bed furnace or in the form of a rotating drum. Sulfur dioxide from furnace 2 enters dust collector 5 and then into the cat. waste heat 6- After the waste heat boiler the circulating gas (SO2) returns

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cycle, apoduction gas is cleaned of dust residues in the electrostatic precipitator 7 and the idaavl vts @. Condensation tower 8, irrigated cold,, -,

 The water reservoir from tower 8 is not expelled (in order to avoid SO2 losses), and, 18kpcd is again being supplied for irrigation. In a condensation tower, gas is released from the main amount of water vapor. After the tower 8, SOz may be subjected to additional drying by known methods or sent directly to production. The flue gases after the heat exchanger 3 enter the waste heat boiler 9 and then go to or can be used to dry the iron sulfate in the form of FeS04 TlizO.

When obtaining sulfur dioxide by calcining the mixture by external heating, the method is carried out in the following way (Scheme 2).

A well-mixed mixture of iron sulfate and pyrite (crushed or flotation pyrites) enters the mechanical continuous muffle furnace 10.

The muffle is heated by flue gases from the outside. Instead of a muffle furnace, other structures or electric furnaces of continuous action can be used. The temperature in the furnace is maintained at 650-750 ° C. The emitted sulfur dioxide passes through the waste heat boiler 1J, where it is cooled to 200-250 °, then enters the heat sink 12 and into the condenser tower 13, which is irrigated with cold water. Gas is cooled in the tower and condensation of water vapor. Cooled and freed from the main amount of water vapor, sulfur dioxide is supplied for drying (or directly into production). In order to avoid SOa losses, the water flowing out of the tower / 5 is not discharged, and after cooling it is again supplied for irrigation. The flue gases from the furnace enter the air preheater 14, where the air entering the furnace of the fuel combustion furnace is preheated. The flue gases then enter the waste heat boiler 15, from where they can be used to dry (dehydrate) ferrous sulfate in the form of FeSO4 UNAO.

The calcine discharged from the furnace (and suspiciously in the form of ResO4) can be used as a magnetic oxide or subjected to oxidation to Fe2O3 in order to obtain an iron oxide pigment or an additional amount of S: O2.

Subject invention

The method of obtaining sulfur dioxide by oxidation of pyrites (pyrite), characterized in that, in order to obtain 100% sulfur dioxide, the oxidation of pyrites (pyrite) is carried out without access of air - by calcining the mixture with iron melt and pyrite by external heating or passing through the mixture in the fluidized bed of heated sulphurous anhydride.