DE71704C - Preparation of the pig iron for the fresh process - Google Patents

Description

IMPERIAL / k

PATENT OFFICE.

PATENT LETTERING

CLASS 18: Ironmaking.

Patented in the German Empire on November 23, 1892.

The present invention relates to improvements to the Bessemer and Siemens-Martin processes for the fabrication of flux iron and steel, if you look at these processes the pig iron in a molten state from the blast furnaces, pig iron mixers or cupola ovens.

The purpose of the same is an increased yield of steel in every heat, thereby achieved that something of the excess heat and the heat-producing metalloids can be found of pig iron for the immediate reduction of iron oxide, which leads to it Metal is reduced and at the same time made into steel with pig iron.

The suggestion has been made several times in the Thomas or basic form Bessemer processes adding iron oxide supplements with the lime to the pear in order to stop the re-blowing period shorten. But this method has always been rejected because it is manufactured in this way Steel was in any case "wild" and over-oxidized.

The inventors have now found that if one proceeds in the manner described below proceeding, one can add a considerable amount of iron oxide and yet one of excess Oxygen free steel is achieved, which behaves very calmly in the forms.

In the Thomas or basic Bessemer process we can use iron oxides such as iron ores that are not too high in silicon and sulfur, but the oxide which, in our experience, has given the best results is that which is produced in the puddling process and puddling sinter (tap cinder) . The sinter that arises when finished iron and steel goods are rolled is also very useful.

In the usual acidic Bessemer process, only phosphorus-free sinter or Iron oxide are needed.

In both the acidic and the basic processes there is uniformity of composition the use of it is of great importance, especially with regard to the percentage of silicon, and in order to maintain this uniformity one often collects what comes from the blast furnaces for the individual units Pig iron in large vessels or mixers holding over fifty tons, and out of which it is then taken out when it is converted into steel.

In order to achieve an increased steel output from a certain weight of pig iron and also to lower the silicon content of pig iron, the inventors set both in the pan that brings the pig iron from the blast furnace and in the mixer or the pears and also in the container which holds the pig iron before it is put into steel is converted, a coarsely ground intimate mixture of the iron oxide or sinter with ground coal, e.g. B. coke dust, and the pig iron is poured onto this mixture. The main part of the iron oxide is rapidly removed from the heat of the molten one

Claims (1)

Metal with the help of carbon, with which it is mingled, and silicon and silicon Carbon in the pig iron is reduced. Experiments have shown that in most of them So much heat is present that about 5 pCt. 'of pig iron this way can redilicate immediately, even if there is no mixer in operation, but only the usual ones Pig iron pans. With the mixer a larger amount can be reduced, since the mass of the metal is much larger and therefore much larger the risk of cooling too great is less than when the pan is used alone will. It is advisable to use 15 to 30 pCt. Coal mixed with the oxide to be reduced; the pans must be pretty hot. The slag that is on the surface of the iron is formed, partly contains too much silicon and too little iron to be able to continue ^ To be useful; sometimes it is advantageous to let them flow into the pear, since they has the advantage of making the lime flow faster. Pateντ claim: Preparation of the pig iron for the fresh process, characterized in that it is the same poured onto a mixture of iron oxide and carbon and then fed into the refining furnace will.