DEP0022793DA - Operation of converters - Google Patents

Description

The usual method of operating a converter is to inject compressed air into the bath at an average pressure of about 2-2.5 atm. introduce and allow the exhaust gases to flow freely through the converter mouth, which is also used as a filling opening.

The invention proceeds in a different way. According to it, an overpressure is generated in the interior of the converter due to stagnation and with it an increase in temperature, preferably by providing a cross-sectional constriction at the mouth of the converter. The simplest way to narrow the cross-section of the mouth is by placing a cover in which there is preferably a central opening. Instead of the cover, a throttle body can also be inserted into the mouth, through which part of the cross-section is sealed off, so that a jam occurs. If necessary, such means which hinder the outflow of the gas, such as throttle internals and the like, can also be relocated more into the interior of the converter. Other means can be provided which generate an overpressure in the converter.

With the new process, the process of the combustion of the iron companions can be influenced. In the usual process, iron components such as silicon and manganese are first discharged into the slag, whereupon the carbon burns. Only then does the phosphorus contained in iron usually pass into the slag. With the new process, on the other hand, it can be achieved that the phosphorus also passes into the slag before the carbon combustion has ended. You are therefore no longer forced to blow out all of the carbon, rather you can end the process when the carbon content has reached the desired level, which can be determined, for example, by taking a sample. This fulfills a long-cherished wish of the metallurgists to put phosphorus combustion before coal combustion with all the known advantages.

In principle, the desired overpressure can be achieved by using a relatively small converter opening, but in many cases difficulties would arise when filling the pig iron and introducing the aggregates.

The preferred embodiment of the invention consists in that a lid is placed on the mouth of the converter after the pig iron and the aggregates have been poured in, as shown in the accompanying figure.

The normal converter is denoted by 1, in the interior 2 of which an overpressure is generated in that a cover 3 made of fireclay or other refractory bricks is placed over the mouth. The lid is fastened in a suitable manner. It preferably has a central opening 4 through which the gases can flow off at an increased speed in accordance with the increased overpressure in the interior of the converter. The renewal of the cover, if it should have been damaged by the strong thermal stress, is possible without difficulty. If necessary, the cover can also be equipped with coolants, e.g. with cooling fins or with water cooling. The cover can be arranged movably on the converter, but can also be brought into the closed position or moved out of it by a lifting device or by a special hydraulic mechanism that works with compressed air or is controlled in some other suitable manner. The lid lifting mechanism is arranged near the converter mouth when the converter is erected. Several covers or other throttling means can also be used alternately, so that one cover can be cooled down or repaired while the other is in operation.

Instead of the cover, an approximately streamlined body can protrude into the converter mouth. The pressure increase in the converter can also be achieved by additionally blowing in gases above the bath, by counterblowing, through built-in components which prevent the smooth flow or by chemical means added for the purpose of increasing the pressure.

Putting on a lid during the pale is also advantageous from a thermal point of view, since the gases are dammed and therefore the heat is better utilized. The temperature can thus also be increased above the usual bath temperatures. The invention can also be used to advantage for wicked pears and similar steels that work in the paleest state.

1.) A method for operating a converter, characterized in that an overpressure is generated in the interior of the converter by damming.

2.) Converter for carrying out the method according to claim 1, characterized by throttle means for the gases flowing out.

3.) Converter according to claim 2, characterized by the incorporation or cultivation of variable cross-sectional constrictions in the vicinity of the outlet opening of the converter.

4.) Converter according to claim 3, characterized in that streamlined throttle bodies are built into the outlet opening.

5.) Converter, Bessemer pear or the like. according to one of the preceding claims, characterized by a cover (3) which can be placed on the converter opening or inserted into the mouth and is designed for the blowing operation and has an outlet opening (4) for the exhaust gases.

6.) Converter according to claim 5, characterized by a lifting mechanism for the cover (3) which is arranged in the vicinity of the converter mouth when the converter is erected.