JP5326116B2 - Hot metal separation method in blast furnace discharge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for improving a separating property of molten iron-slag by preventing the disturbance of the molten iron surface in a molten iron tapping trough caused by the molten iron tapping-off of the molten iron-slag from the molten iron tapping hole in a blast furnace, and also preventing the molten iron from riding over a slag overcoming part and flowing into a slag trough by promoting the laminar flow. <P>SOLUTION: In the method for separating the molten iron and the slag with a difference between the specific gravitations thereof, through a skimmer 3 arranged at the down-stream of the molten iron tapping trough 1, to the molten iron and slag discharged from the molten iron tapping hole 2 in the blast furnace; in the up-stream side molten iron tapping trough of the skimmer 3, a damper 6 for restraining the molten iron level provided projectingly from the inlet part of the slag trough toward the inside wall of the molten iron trough at the opposite side of the above inner part is provided. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention prevents the molten iron from flowing into the slag recovery dredger in the method of separating the molten iron discharged (unloaded) from the blast furnace outlet into the molten iron and slag. Thus, the present invention relates to a hot metal separation method suitable for improving the separation property of hot metal and hot metal.

  A blast furnace is a facility for producing hot metal by reducing iron ore, sintered ore, etc., which are raw materials, with coke. During the production of hot metal using this blast furnace, the gangue components (alumina, silica, magnesia, etc.) contained in the raw material are also generated simultaneously as hot metal. The mixed hot metal is discharged to the blast furnace output (hereinafter simply referred to as “extraction”).

  The hot metal is separated into hot metal (hereinafter referred to as “slag”, upper layer) and hot metal (lower layer) using the specific gravity difference in the output, and is arranged downstream of the output. The slag is recovered as a slow-cooled slag in the granulated slag production facility or dry pit through the slag, which is provided on the furnace body side of the skinmer, and the molten iron is It passes under and is discharged into the topped car through hot metal.

  The slag collected in this way is used as roadbed material, cement, aggregate for concrete, etc. If slag is mixed with hot metal (pig iron), rust is generated or crushed. There is a possibility that quality will be degraded such as a longer time required, or that a steam explosion may occur during the production of granulated slag. Therefore, it is considered important to develop a technology that completely separates hot metal from slag and hot metal.

For example, Patent Document 1 provides a damper so as to create an appropriate gap in the molten iron flow upstream of the blast furnace outflow, stops the momentum in the center in the width direction where the flow velocity is fast, calms down, and mixes in the slag. Disclosed is a method for preventing hot metal from flowing into the hot metal by facilitating the settling of the hot metal.
Patent Document 2 discloses a method in which the molten slag surface layer flow in the center portion of the large ridge width direction where the flow velocity is high is dammed by the upper dam, the flow velocity distribution in the large ridge width direction is made uniform, and the molten iron dispersed in the molten slag is settled. Disclosure.
Japanese Patent Laid-Open No. 10-273706 JP-A-8-176628

However, the method described in Patent Documents 1 and 2, with the high pressure in recent years furnace pressure, the flow rate of molten iron slag tapping from a blast furnace taphole is increased, when the open mouth of the blast furnace and tapping initial In an environment where hot metal such as hot metal is prone to bumping and the turbulence of the hot metal flow is large, it does not provide sufficient countermeasures. Because of laminar flow inhibition, there was a big problem that the hot metal crosses over the iron inlet (hereinafter also referred to as “the iron splash part”) and flows into the iron.

  Therefore, the present invention prevents the molten iron surface from being disturbed in the tapping process accompanying the tapping of molten iron from the blast furnace tapping port, and promotes laminarization, so that the molten iron gets over the spear splashing part. The purpose is to establish a technology to improve the separability of hot metal by preventing it from flowing into the iron.

As a method of overcoming the above-mentioned problems of the prior art and realizing the above object of the present invention, the present invention is provided with hot metal discharged from the blast furnace outlet at the downstream of the brewery. In the method of separating the hot metal and slag through the skinmer due to the difference in specific gravity, the slag is discharged into the hot metal, while the hot metal is discharged into the hot metal to separate the hot metal and the slag, it is located upstream of the skinmer. in blast furnace Dezukutoi that, from the slag splashing unit therewith toward selfish blast furnace out Zukutoinai sidewall opposite sides, and the molten iron level suppression damper which projects in the width direction of the blast furnace tapping trough is provided We propose a method for separating hot metal from blast furnace discharge.

  In the present invention, the hot metal level suppressing damper is disposed such that the upper surface thereof is below the hot metal bottom level, and the hot metal level suppressing damper is disposed between the lower surface and the hot metal inner bottom surface. A diving space is provided; the hot metal level suppressing damper is provided with a cutout between the hot metal inner wall on the side facing the hot metal; and the length of the cutout in the hot metal width direction. The length of the hot metal level suppressing damper is 1/2 to 4/5 of the hot metal width, and the length of the hot metal flow direction is larger than the width of the hot metal, A preferred solution can be provided.

According to the present invention employing the above-described summary configuration, the following effects can be obtained. That is, the present invention promotes stable laminar flow (two laminar flow of molten iron and slag) from the molten iron flow by providing a damper for suppressing the molten iron level during the blast furnace discharge at the molten iron inlet. Can do. Especially, according to the present invention, with varying promptly subsided to rectify the flow velocity of the large tapping stream turbulence when Dezukuguchi open mouth or during furnace situation is not stable, near slag splashing portion In addition to preventing hot metal turbulence associated with hot metal jetting and bumping from the blast furnace outlet, it is possible to prevent the hot metal from flowing into the hot metal by suppressing the rise of the hot metal level. Can be improved.

  Hereinafter, an example of an embodiment of the present invention will be described with reference to the drawings. Fig.1 (a) is a top view which shows the whole of the blast furnace tread 1 for implementing the method of this invention, FIG.1 (b) is an enlarged plan view of a soot inlet part. FIG. 2 is a partial cross-sectional view of the ridge entrance.

  In general, the hot metal separation method using the blast furnace feed 1 is such that the hot metal discharged from the blast furnace feed port is laminarized during the flow of the blast furnace feed 1 and then the difference in specific gravity is caused by 3 parts of skinmer. The slag is separated into hot metal, and the slag is led to the spear splashing portion 4a and flows out to the spear 4. On the other hand, the hot metal is led to the hot metal 5 under the damper-shaped skinmer 3. By separating and discharging.

  In the present invention, in the hot metal separation method described above, in the vicinity of the inlet of the blast furnace 4 in the blast furnace outlet 1 on the upstream side of the skinmer 3, that is, from the side of the slag splash portion 4a, It is characterized in that a hot metal level suppressing damper 6 is arranged toward the inner wall 7 of the iron. This hot metal level suppressing damper 6 is disposed as shown in FIGS. 1 (a) and 1 (b), and is disposed on the blast furnace discharge inner wall 7 on the side facing away from the iron splashing portion 4a. On the other hand, it is erected in the width direction of the blast furnace outlet 1 so as to block the flow of hot metal.

  By using this damper 6 for suppressing the hot metal level, the hot metal flow is temporarily blocked at the surface layer, the flow velocity is calmed down, and the hot metal surface is disturbed by the hot metal in the vicinity of the hot water splashing portion 4a. (Wavy) is suppressed. As a result, it is possible to promote the separation of the hot metal and the slag from the hot metal.

  As shown in FIG. 2, the hot metal level suppressing damper 6 has an upper surface 11 positioned at the boundary surface between the hot metal and the slag in the blast furnace discharge 1 at a bottom level 10 or lower. Because it is installed, it acts to suppress the inflow of hot metal below the hot metal level suppression damper 6 into the hot metal 4 and ensures that hot metal flows into the hot metal 4 even if the hot metal has a turbulent flow. Works effectively to prevent.

  Further, as shown in FIG. 2, the hot metal level suppressing damper 6 is provided with a dive space between the lower surface and the inner bottom surface of the hot metal for flowing only the remaining hot metal flow skimmed with the slag. It is what. This submerged space has a size that is effective for preventing slag from mixing into the hot metal 4 while adjusting the thickness 6c of the hot metal level suppressing damper 6 in the depth direction 1 of the hot metal. It is required to be a space.

  The hot metal flow temporarily blocked by the hot metal level suppressing damper 6 is smoothly laminarized and separated into slag and hot metal, and then the slag is discharged from the hot metal level suppressing damper 6 and the blast furnace. It is discharged to the gutter 4 through the cut-out 9 that is a gap with the gutter inner side wall 7 and the hot metal level suppressing damper 6. On the other hand, after the hot metal dives below the hot metal level suppressing damper 6 or after passing through a cut 9 which is a gap between the hot metal level suppressing damper 6 and the inner wall 7 of the blast furnace, the hot metal passes through the lower part of the skinmer 3 and is molten. 5

  The cut-out 9 smoothly guides the hot metal staying in the vicinity of the hot metal level suppressing damper 6 due to excessive hot metal flow to the downstream side, and allows the slag exceeding the upper surface of the hot metal level suppressing damper 6 to be mixed without hot metal being mixed. It is effective to guide it into the tub 4 and let it flow. In addition, it is recommended that the length 9a of the cut-out width 9 is 1/2 to 4/5 of the width 1a. This is because if the cut-through 9 becomes too small, the effect of the molten metal level suppressing damper 6 cannot be obtained, and the molten metal level suppressing damper 6 becomes a weir to inhibit rectification and laminarization of the molten metal, This is because the hot metal may flow over the hot metal level suppressing damper 6 and into the hot metal 4. That is, by setting the length 6b of the hot metal level suppressing damper 6 to ½ or less of the hot metal width 1a, the hot metal does not exceed the hot metal level suppressing damper 6. Further, the length 6b of the hot metal level suppressing damper 6 is set to at least 1/5 of the hot metal width 1a, so that the hot metal rectification and laminarization effects can be exhibited. .

  Further, in the present invention, in order to suppress the inflow of hot metal into the hot metal 4 and to ensure a smooth flow of slag into the hot metal 4, as shown in FIG. It is recommended that the hot metal flow direction length 6a of 6 be larger than the hot metal width 4b to enhance the slag separation function.

  Furthermore, as shown in FIG. 2, the installation position of the hot metal level suppressing damper 6 and the thickness 6c of the hot metal level suppressing damper in the hot metal depth direction are within the range of the thickness 6c. Is preferably set to exist. This is because if the installation position of the hot metal level suppressing damper 6 is too low, the hot metal surface turbulence (waving) cannot be sufficiently suppressed on the surface layer, while the hot metal level suppressing damper 6 is installed. If the temperature is too high, the hot metal level suppressing damper 6 acts as a weir to inhibit the flow rectification and laminarization of the hot metal, and the hot metal may flow into the hot metal level suppressing damper 6 and mix hot metal into the slag. Because there is. In other words, if the interface between the hot metal and the hot metal exists in the thickness 6c range of the hot metal level suppressing damper 6, the rectification and laminarization effect of the hot metal level suppressing damper 6 can be stabilized. it can.

  The method for separating hot metal in the blast furnace discharge according to the present invention can be suitably used when the cast iron floor area is small or when the discharge speed from the blast furnace is high, and has other similar facilities. It can be applied to molten metal processing facilities.

It is the top view (a) of the blast furnace discharge which arrange | positioned the hot metal level suppression damper by this invention, and the enlarged plan view (b) of the hot metal inlet part. It is an expanded sectional view of the iron inlet part of the blast furnace tapping where the damper for suppressing the hot metal level according to the present invention is arranged.

Explanation of symbols

1 Blast Furnace Outlet 1a Outgoing Width 1b Length from Outgoing Bottom Level to Outgoing Bottom Level 2 Blast Furnace Outlet 3 Skinmer 4 滓 樋 4a ａ Splash 4b 滓 樋 Width 5 Hot Metal 6 Hot Metal Level Suppression damper 6a Hot metal level control damper Hot metal flow direction length 6b Hot metal level control damper Outlet width direction length 6c Hot metal level control damper Outlet depth direction thickness 7, 8 Blast furnace outlet inner wall 9 Cut-out 9a Cut-out width direction length 10 Fillet bottom level 11 Upper surface of damper for suppressing hot metal level

Claims (6)

The hot metal discharged from the blast furnace outlet is separated into hot metal and slag by the specific gravity difference through the skinmer provided downstream of the hot metal, while the slag is discharged into the hot metal, while the hot metal is molten a method to achieve separation of molten iron and slag are discharged to the gutter, in the blast furnace Dezukutoi located upstream of the skimmer from the slag splashing unit, therewith to blast out Zukutoinai sidewall opposite sides direction Thus, a hot metal leveling damper provided in the width direction of the blast furnace feed is provided with a hot metal level suppression damper, wherein the hot metal is separated in the blast furnace feed.   2. The method for separating hot metal in a blast furnace discharge according to claim 1, wherein the hot metal level suppressing damper is disposed such that an upper surface thereof is equal to or lower than a bottom surface level. 3.   3. The hot metal separation method according to claim 1 or 2, wherein the hot metal level suppressing damper is provided with a submerged space between a lower surface thereof and an inner bottom surface of the hot metal.   The blast furnace exit according to any one of claims 1 to 3, wherein the hot metal level suppressing damper is provided with a cutout between the hot metal inner wall on the side facing the hot metal. A method for separating hot metal in a cocoon.   The hot metal in the blast furnace discharge according to any one of claims 1 to 4, wherein the length of the cut through in the width direction of the hot metal is 1/2 to 4/5 of the hot metal width. Separation method.   In the blast furnace discharge according to any one of claims 1 to 5, wherein the hot metal level suppressing damper has a length in the hot metal flow direction larger than a width of the hot metal. Hot metal separation method.

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