SU1408175A1 - Reverberatory furnace for melting scrap and waste of non-ferrous metals - Google Patents

Abstract

The invention relates to metallurgy, in particular, to the design of two-chamber reflective furnaces for melting metal charge, and can be used in secondary non-ferrous metallurgy to produce alloys from scrap metal and non-ferrous metal waste. The aim of the invention is to reduce specific fuel consumption and buildup in the gas path. With the passage of the second pinch, the gas velocity decreases, due to the installation of the partition, the direction of gas movement changes, which contributes to the precipitation of large and molten particles to the bottom of the slag located between the second pinch and the partition, reusing radial heat flux reflected from the partition due to its concave spherical outline surface; mechanical underburning of the fuel is reduced, since the heated partition acts as a glowing body and on its surface combustion of the organic components of the flue gases takes place. 1 hp f-ly, 3 ill. (Oh (L

Description

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The invention relates to metallurgy, in particular, to the design of two-chamber reflective furnaces for smelting metal charge, and can be used in secondary non-ferrous metallurgy enterprises for producing alloys of metal scrap and non-ferrous metal waste.

The purpose of the invention is to reduce the specific fuel consumption and build-up in the gas path.

FIG. I shows a reflective furnace, a longitudinal section; in fig. 2 is a section A-A in FIG. ; in fig. 3 is a section BB in FIG. one.

Reflective furnace for smelting scrap and non-ferrous metal waste contains a body 1 lined with refractory material with a gas path 2, communicating with a metal collector 3 located under it, a melting chamber 4 and a vertical chimney 5. The metal collector 3 is located in the front part of the reflector 1 ovens. It is bounded from below by the bottom 6, from the front by the end wall 7, from behind by the front step 8 of the melting chamber 4, from the sides by the side walls 9 and 10, from above by the arch 11. On the end wall 7 there are burners 12, the axis of symmetry of which parallel to the longitudinal axis of the furnace and passes through the centers of the metal of cross sections of the metal tank 3 baths and the melting chamber 4.

Zavalochnye Windows 13 are located on the side wall 9 and provided with flaps 14, and on the opposite side wall 10 is located the outlet tap 15.

The melting chamber 4 is located behind the metal collector 3. It is located above the metal collector 3 and bounded at the front by the front wall 8, from the bottom - the bottom 16, from the rear - the rear wall 17, from the sides - the side walls 9 and 10, and from the top - the arch 18. On the side wall 9 of the melting chamber 4 is provided with charging holes 19 with shutters 20, and in the front wall 8 in the immediate vicinity of the side wall 10 there is a downstream channel 21 for transferring the molten metal from the melting chamber 4 to the metal container 3.

A vertical wall 22 is located above the front wall 8 on which the burner 23 of the melting chamber 4 is installed. The vertical wall 22 and the front wall 8 of the melting chamber form the first pinch 24 of the gas path 2. The second pinch 25 of the gas path is formed by the back wall 17 and the inclined arch 26 of the melting chamber 4. Behind the second clamp, there is a partition 27, the upper edge of which is located with the overlap of the second clamp 25 of the gas path 2 in height, and the front surface of the partition is made concave spherical. The space between the second clamp 25 of the gas path 2 and the partition 27 can be used

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It was used as an additional slag 28. A slag passage 29 or a window 30 with a flap 31 is provided to remove the liquid slag. The cross section ratio of the second pinch of the gas path and the cross section of the duct 32 above the partition 27 are selected within 1: (1.25 ... 2 , 0).

The first ratio (1: 1.25) is determined by the condition that prevents the creation of additional resistance in the gas path due to the installation of a partition, which is ensured by an increase in the cross section of the duct 32 above the partition 27 by 26%. The second ratio (1: 2.0) is determined by the minimum permissible gas flow rate, since with a larger ratio of cross sections, the gas velocity over the partition 27 decreases more than twice, which leads to the overgrowth of the upper cut of the partition 27 by entrainment.

Vertical flue 5 is connected to the hog 33.

The furnace works as follows.

After drying the furnace, the burner 23 of the melting chamber 4 is put into operation and, at the same time, through its loading windows 19, the meter and waste of non-ferrous metals are introduced into the chamber. When fuel burns, the torch of the burners 23 of the melting chamber 4 flows around the bath, heating it and melting the charge. From the beginning of the accumulation of the liquid metal in the metal container 3, the burners 12, located on the vertical wall 7 of the metal container 3, are turned on to maintain the temperature at a given level. As the metal accumulates in the metal collector 3, it is refined to a predetermined composition and discharged through the tap hole 15.

The flue gases of the burners 12 of the metal collector 3 release part of the heat to the liquid metal, then through the first pinch 24 they enter the melting chamber 4, where they give off heat to melt the metal and, mixing with the gases formed during the operation of the burners 23 of the melting chamber 4, through the second pinch The window 25 enters the space above the slag 28, where on its way they meet the partition 27, change their direction and through the flue 32, the vertical channel 5 goes to the hills 33.

Since the cross section of the duct 32 above the partition 27, as well as the space above the slag, is larger than the cross section of the second pinch 25, the velocity of the flue gases at the exit of it decreases, in addition, the gas flow, meeting the barrier in the form of a partition, changes its direction - all this promotes the precipitation of large particles of dust from the gas stream to the slag 28. Small dust particles and unburned fuel components (soot) are entrained by the gas flow to the partition 27. As the partition 27 is heated, the washout 1 of its gases to high

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temperature, on its surface, the burning of organic components of gases and the melting of small particles carried away. In addition, due to its concave spherical surface, the partition concentrates and reflects the radiant energy in the direction of the second pinch 25 of the melting chamber, thereby reducing heat loss in it and maintaining the entrainment in the fluid-mobile state and, therefore, easier removal of it from the slag 28 without stopping ovens.

The application of the proposed furnace ensures complete elimination of melting dust in the liquid metal, reduces the gas content of the metal melt in the metal collector, reduces the formation of gas in the duct and the dust content in the flue gases, reduces downtime of the slag cleaning furnace, and reduces the specific fuel consumption.

Claims (2)

Claim 1. Reflex furnace for melting scrap and non-ferrous metal waste, containing a housing with a gas path connected to a metal collector located under it, a melting chamber with front and rear walls connected to a metal collector with an overflow channel and having pinch of the gas path above the front wall, burners installed in the gas path above the metal collector and melting chamber, and a vertical gas duct, characterized in that, in order to reduce specific fuel consumption and build-up in the gas path, it is equipped with an additional clamp, located above the rear wall of the melt second chamber and mounted behind them partition whose upper edge is situated above the top edge of the additional pinch, wherein the front surface of the partition is concave, spherical form. 0 2. The furnace according to claim 1, characterized in that the ratio of the cross sections of the additional clamping and the cross section of the gas path above the partition is 1: (1.25 ... 2.0). 3168 13 9/4 1Л 25 22 18 2 26 - 27 J2 / I 25 " A- / 19 20 JU 30 51 Rig.