A method for increasing carbon and desulfurizing phosphorus pig iron

Abstract

The invention relates to the field of aluminum electrolysis production, in particular to an environment-friendly phosphorous pig iron additive, a preparation method of the environment-friendly phosphorous pig iron additive and a phosphorous pig iron recarburization and desulphurization method. The environment-friendly phosphorous pig iron additive is prepared by pressing 95.5%-98.5% of a carbon material, 1.0%-3.5% of a binder and 0.5%-1% of carbonate by mass percent into a pellet. The carbon material is solid carbon obtained by carrying out vacuum metallurgy treatment on waste cathode carbon blocks. The preparation method is simple, the prepared additive is low in cost, and the recarburization and desulphurization effect on phosphorous pig iron is good. The phosphorous pig iron recarburization and desulphurization method comprises the steps that the additive and a phosphorous pig iron raw material are added into an intermediate frequency furnace in a layered manner, and then smelting is carried out. The method is high in carbon absorptivity and good in desulphurization effect, meanwhile, material flying losses in the phosphorous pig iron recarburization and desulphurization process can be effectively reduced, and the workshop environment can be improved; and the flowability phosphorous pig iron liquid is good, and the obtained phosphorous pig iron meets the requirement of phosphorous pig iron for prebaked anode casting.

Description

technical field [0001] The invention relates to the field of aluminum electrolysis production, and in particular to a method for increasing carbon and desulfurizing phosphorus pig iron. Background technique [0002] In the production of aluminum electrolysis, the prebaked anode is called the "heart" of the electrolytic cell. The prebaked anode is composed of an anode carbon block and an aluminum guide rod, specifically the gap between the steel claw of the aluminum guide rod and the carbon bowl of the anode carbon block. The phosphorus pig iron water is poured, and after cooling, the anode carbon block and the aluminum guide rod are combined into one, and the phosphorus pig iron plays the role of connection and conduction. Reducing the Fe-C pressure drop of the prebaked anode is one of the ways to reduce the production cost of electrolytic aluminum, and practice shows that adjusting the element ratio of phosphorus pig iron is the best way to reduce the Fe-C pressure drop. ...

AI Technical Summary

Problems solved by technology

However, graphite is very easy to float on the surface of high-temperature molten iron during the addition process, resulting in oxidation, and is easy to fly, resulting in large physical and chemical losses of recarburizer graphite, and finally leads to low carbon absorption rate and poor carburization effect

[0005] The Chinese patent with publication number CN105154621A discloses a method for preparing a carburant for steelmaking. The method aims to maximize the use of fine coke particles produced during the CDQ production process in a coking plant. Screening and other processes are used to prepare recarburizers for steelmaking production, but because CDQ uses inert gas to cool red coke (1000°C) to room temperature, the coke powder produced by dust collection is produced, so the quality of coke powder is relatively low. Poor, the degree of graphitization is not high, the carburizing effect of the coke powder as a recarburizing agent is poor, not as good as that of calcined coke, let alone comparable to graphite

[0006] The Chinese patent with the publication number CN101570803B discloses a phosphorus pig iron desulfurizer for prebaked anode casting. In this technology, it is disclosed that the composition of the desulfurizer is: 2-4% graphite, 35-45% CaO, 3-5% CaF 2 , 1~3% Na 2 CO 3 , 40-50% Na 2 SiO 3 , 1 to 3% FeO, and the addition of desulfurizer is 2.5%. The desulfurizer is used on a 1.6-ton induction furnace, and the composition and performance of the produced phosphorus pig iron meet the requirements for use. However, in order to realize the recycling of phosphorus pig iron, this technology Not only a desulfurizer is used, but also graphite is added as a carbon increaser, the raw materials are complicated and the processing cost is expensive

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