SU908808A1 - Blast furnace main chute - Google Patents

Description

(54) MAIN CHAIN OF DOMAIN FURNACE

I

The invention relates to a public sector where it is necessary to separate the flows of two immiscible liquids, in particular to the blast furnace, and can be used in chutes for the production of pig iron from the blast furnace.

The most blinding to the proposed technical essence and the achieved results is the main domain chute, which, to increase the efficiency of the separation of iron and slag, is installed between the slag ditch and the cast iron vent of the refractory partition in the middle height of the part of the gutter in the zone of the intermediate layer, where the shpak – hinge layer of the hinge layer flows through the layer of the channel. the efficiency of the separation of the flow of iron and slag is achieved in this device for. the expense of installing a refractory partition in the head of the chute to meet the flow of liquid melts. The droplets of cast iron moving with the slag gap and dispersed in it, when they strike the partition, lose kinetic energy and, under the action of gravity, are dipped down into the metal bath 1.

Known main trough does not provide effective. the separation of pig iron and slag at high flow rates of melts due to the additional dispersion of large Kuieitb pig iron into smaller ones due to an excess of kinetic energy p striking them against the threshold. Small drops of chutun are easily carried away with the slag flow. This is especially pronounced because of sharp fluctuations in the rate at which the product is melted.

10 because of the pstadan into the channel of the cast-iron plate of pieces of coke, the change in the cross section of the bottom hole, the change in the hydrodynamic parameters of the coke nozzle and the fietchesquh properties of the slag in the secondary sections adjacent to the cast iron

ts letke. At the same time, the instantaneous yield rate of the product from the tap-hole production can vary from 0 to 30-50 tons / mission, which leads to strong dispersion of the iron and 1lac drops and even to

20 to loss of metal with slag.

The purpose of the invention is to increase the efficiency of the separation of iron and slag in the main chute of the blast furnace at high speeds 39 of the movement of the melt flow and uneven delivery of ira products in time. This goal is achieved by the fact that in the main trough, which includes a skimmer plate and an additional refractory partition, installed between the cast-iron taphole and a slag-withdrawing ditch, the refractory partition or its surface facing the cast-iron taphole is inclined opposite to the flow of liquid melts at an angle of 58 ° horizontally. Tilting the refractory partition reduces the dispersion of metal droplets due to the fact that part of the kinetical energy in a collision of cast iron droplets with a partition is not spent on dispersion, but provides a drop of iron along the partition surface to contact with the bath. metal, which contributes to the additional loss of metal droplets and their more complete separation from the slag. In this case, the angle of inclination of the refractory partition is chosen to be equal to or less than the scattering angle (relative to the horizontal) of the secondary (after dispersion upon impact of the partition) of the metal drops. The drawing shows the main chute of the blast furnace with a refractory partition, the sloping surface of which is facing the cast-iron notch, a transverse section. The skimmer plate 1 is located at the end of the main chute 2 of the blast furnace, and the slagging channel 3 adjoins the skimmer bar 1 directly. The additional refractory partition 4 with an inclined surface is installed at some distance from the slagging channel 3. In the main chute 2 at the time of cast iron Slag melt 5 with individual drops of 6 pig iron suspended in it is located above the layer of molten iron 7. Example. In the main trough 2 blast furnaces with a skimmer plate 1 at 700 mm from the axis of the slag removal channel 3 on both its side walls, the fireproof packing and fireclay masonry are disassembled to the width of one brick. Vertically, the lining is disassembled at 400 mm, counting from the slag pass. Additional refractory walls 4 are made of a graphite block, for which they are cut according to the cross section of the main gutter (without refractory stuffing) at the place of installation of partitions On the side edges of the fireproof partitions make projections on the thickness of the fireclay masonry. The surface of the refractory partition, subject to a cast-iron notch, is cut off so that the angle a between the horizontal and this surface is 75 ° (drawing). An additional fire-resistant partition is inserted into the grooves on the side walls of the main trough. The gaps and cracks are filled with a refractory mass and the mass is packed until it is level with the level of the old lining. For 30-60 minutes, freshly lined, 1 st place of the main trough is dried with an oxy-flame burner. After drying, cast iron is produced. In the second half of the release, when both the iron and slag come out of the hearth through the cast-iron tavern, dispersed and pig iron streams in the slag disperse in the tap-hole channel. When leaving the canal, the largest drops and streams of cast iron settle to the bottom of the main gutter, forming a metal bath. A considerable part of the 6-cast-iron droplets with a size of less than 7-10 mm is long (as compared with the residence time in the main runner) the time is suspended in the slag flow. When the iron drops hit the inclined surface of the refractory partition, part of the kinetic energy of the drops is converted into heat, part of it is spent on the process of dispersing the drops into smaller ones, but due to the inclination of the surface of the partition, the main part of the drops of iron cannot be carried away with slag due to the presence of friction forces septum and settles down. Part of the energy from the impact of the cast iron droplets on the partition in connection with its inclination towards the oncoming melt flow causes a force and moment of movement directed downward at an angle a to the horizontal. This force is directed in the same direction as the force of gravity, and therefore it is folded with it and in connection with this contributes to a more rapid and complete separation of the pig iron from the slag. Through the partition with slag, only the smallest (less than 0.5-1.0 mm) droplets of cast iron are removed. Additional fireproof walls can be made by casting from steel with ribs, with a brick and smooth with a previously given, inclined surface at an angle with / and flat. After installation in the main groove, the refractory partition is lined with a gasket of the refractory mass, in particular for driving a cast iron notch. With the help of this mass, the required slope of the surface of the partition wall (o) can be measured, and also a change (regulation) of this inclination in intrusion can be made from the expected rate of mining of the smelting products, the state of the hearth for heating and slag properties.

The use of the proposed design of the main chute of a blast furnace makes it possible to reduce losses of iron with slag by 0.41, 5 abs.%. In addition, the service life of slag trucks increases as a result of a reduction in iron casting and thermal cracking. An additional effect can be achieved by reducing the amount of slag falling into chitunovoznye buckets, by reducing the cross-section of the hole between the skimmer gauge and the bottom of the main trough, since installing an additional refractory partition in the main chute eliminates large masses of pshak in the chunks . With this, the casting of the bucket ladles is reduced.

as well as an improvement in the conversion rate.

Claims (1)

Invention Formula The main trench of the blast furnace containing a skimmer bar and an additional refractory partition installed between the cast-iron tap and a slagging ditch, characterized in that, in order to improve the separation of iron and slag, an additional fire-resistant partition is made with an inclination of the front wall of 60-85 ° to the horizontal plane. Sources of information taken into account in the examination 1. Japanese patent And 50-38366, cl. 10 A 525, published. 1975.