JPS5819681A - Rotary furnace - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a rotary furnace KIl for smelting raw materials by rotating a furnace body charged with raw materials. This smelting method uses carbon ferrochrome ore, a reducing agent such as coke, and a slag-forming agent such as limestone and silica stone as raw materials, and smelts it by continuously charging it into a submerged arc furnace. So, the power consumption of high carbon ferrochrome raw wL 1 ton Todoroki is about 3o00
It can be said that it is a typical power consuming industry, requiring up to 3,700 KWH.

Nowadays, energy-saving technology is being called for, and the development of technology that avoids the use of large amounts of inefficient and low-efficiency electricity when converting liquid fuel into electrical energy is an urgent and important issue.

From this point of view, for example, nutrients @ 44-23.71
As seen in Publication No. 31, a method for manufacturing alloy iron or alloy steel by the 11-fusion method using a rotary furnace has been proposed. As shown in FIG. 1, this rotary furnace has an outer periphery surrounded by an iron shell 2, a charging port 06 for raw materials and an attachment port 4 for a fuel blowing lance 5 on both sides, and a furnace body 1 attached to a roller 6. The iron skin 2 has a refractory material 7 lined on its inner surface. Then, the raw material 8 is charged into the rotary furnace, and while the furnace body 1 is rotating, it is directed from the lance 5 to the refractory on the ceiling. ! The material is smelted using the radiant heat that is smelted by spraying and burning it.

These gold rotary furnaces have the following problems:
This has caused various problems in practical use.

(1) Coal or coke, which are expected to be cheap and stable in supply, cannot be used. (2) According to the results of experiments, when the surface temperature of the refractory in the furnace exceeds 1900°C, slag will cause cavitation. It became clear that the amount of consumption increased rapidly as the
In this rotary furnace, the surface temperature of the refractory is 2000℃
As it reaches this point, it is subject to heavy wear and has to be replaced frequently, which not only increases repair costs, but also causes significant loss of time after replacement.

(3) Since the raw materials are melted by radiant heat from the refractory, blowing takes time.

(4) C-saturated gold I14 is produced depending on the type of carbon used as a reducing agent. The present invention is designed to solve these problems.
It is a method in which the inner wall of the rotary furnace body is filled with a plurality of small holes or porous refractories to form small holes, and gas and/or fuel is injected through the small holes. (υ Use coal and coke, which are cheap and have a stable supply.

(2) Prevents overheating of refractories in the furnace and reduces consumption.

(3) Inject fuel and oxygen to promote melting of raw materials, shorten blowing time and improve productivity. (4) Decarburize the produced metal.

It is intended for this purpose. The present invention will be explained below with reference to the drawings.

FIG. 2 is a theoretical longitudinal sectional view of the rotary furnace according to the present invention, 183
The figure is the person-mu section wIWIA in the 0 figure, 10
A furnace body, 11 is an iron shell, 12 is a refractory placed on its inner surface, 16 is an oxygen inlet and a raw material charging port provided on both sides of the furnace body 10, and o14 is an iron shell 11 and a refractory 12. A small through-hole may be filled with porous refractory material as required. 21 is a run for oxygen blowing, 22 is metal, 25
is a slag, and 24 is a reducing agent. When the rotary furnace constructed in this way is rotated, the metal 22, slag 23, and reducing agent 24 are in the range w#A, and the range B is space, as shown in FIG.

FIG. 4 shows an example of the small hole 14 provided in the furnace body 10, (a)
Insert the pipe 15 into the hole 14, and insert the gas pipe 19 into the hole 14.
In (b), the small hole 14 is covered with an iron skin 17 and the porous refractory 16 is inserted, and the gas pipe 19 is connected to the W! In (C), a double pipe consisting of an outer pipe 18 and an inner pipe 18m is inserted into the small hole 14, and each gas pipe 19.2
It is connected to 0.

According to the present invention, Table 1 is applied to the small hole of the rotary furnace configured as described above.
It is characterized by blowing gas as shown in the figure below.

Next, an example of manufacturing ferrochrome using the rotary furnace of the present invention will be described. Example 1 This example is an example of manufacturing medium carbon ferrochrome. - and a two-day rotary furnace of the structure shown in Fig. Keeping the axis of rotation horizontal, rotated at 8r, Ip 0
This rotary furnace is provided with small holes 14 that lead from the iron IL 11 through the refractory 12 and into the furnace at 5 locations every 50 mm in the length direction and 6 locations at equal intervals on the circumference, for a total of 60 locations. As shown in the embodiment of FIG. 4, each small hole 14 is connected to a pipe 19 leading to a gas source. 7joCriE stones charged inside: 1
90011w, burnt lime = 254 noodles, silica: 26 suke, pig iron slag: 5 to 4, coal: 400-, coke: 400 Next, Sanso is injected from the blowing al bulk injection lance 21, and at P1,
Air is caused to flow through each of the small holes 14 in the metal and slag producing area (range A) and the space area (range B) in the furnace. Here, air is flowed into the metal and slag generation areas to promote dissolution of the raw materials, and air is flowed into the space to cool the refractory surface.

Approximately 28 minutes after the start of MIA blowing, the raw material melts and the slag temperature reaches 1620°C.
The gas blown into the small hole 14 in the metal, slag generation area and space was changed from air to exhaust gas (#gas 1N5). Approximately 60 minutes after the start of oxygen blowing, the slag The temperature was 1710c and the amount of metal produced at this point was 990c, and the chemistry of metal! iH1, is s 54-
0*Cr-a8% C-36-596Fe and 7H.

From 60 minutes until the end of smelting, Metal, Slada Raw I
li, s minute (muno range 18'') o small hole 14 to Ar+Os
was allowed to flow, and exhaust gas was allowed to flow from the small holes 14 in the space portion (range B!B). The blowing was completed in 80 minutes and the hot water was tapped.The metal, slag amount, and chemical composition at this time were as follows:〇Metal: 9401j Chemical composition: 55-2%Crt4.0%C ,39,0%
Fe.

1, 21! Sl slag: 13004 Chemical composition: 2.2%Cry's e 16*5io
ts 27%Ca0s28% ノ1A5tOs
, 26% RagO Figure 7 shows the above Example 1.
This is a diagram showing the relationship between the passage of time and the gas injection amount, metal production amount, raw material/slag temperature, and oxygen blowing amount. The Umazo example was manufactured by the following method.

Rotary Furnace Co., Ltd., with the structure shown in Figure 8, with an inner diameter of 1 m, an outer diameter of 2 m, and a length of Svn.
A rotary furnace with nine openings lined with a thickness of There are 11 iron shells to 12 large objects in 6 places at equal intervals on the top, 30 places in total. A small hole 14 is provided that communicates with the inside of the furnace through the outer tube 18 and the inner tube 1.
Double pipe consisting of 8a (outer diameter: 15-1 inner diameter 11 sm
) connected to the gas source.

Examples of connections between the double pipe and the gas source are shown in FIGS. 9, W, and 10. FIGS. The outer pipe connecting device 30 connects the outer pipe gas to the metal and slag generating parts.
3. A fixed block 31 having a gas port 34 for the outer pipe into the space and grooves 33m and 34a leading thereto, and a rotating block 32 having a plurality of small holes 191 leading to the gas pipe 19 for the outer pipe, both of which are integrated. As the rotary furnace rotates, the rotary block 62 is rotated and slid along the direction of the fixed block 31, and the gas from the gas source is transferred to the outer tube 1.
8 to the metal, slag generating section and space section of the furnace.
This is an example of a connection between an 8 m gas pipe 20 and a gas source, with 35 internal pipe connection devices, a gas inlet 38 for the inner pipe to the metal and slag generation part, a gas inlet 39 for the inner pipe to the space part, and grooves 38a and 39 leading to this. A donut-shaped fixed block 56 with a sill and a plurality of small holes 2 communicating with the inner gas pipe 20.
The rotary block 37 is rotated along the end face of the fixed block 66 as the rotary furnace rotates, and the gas from the gas source is passed through the inner pipe 18a into the furnace. In addition, the outer pipe gas passage 6
3m and 34m are arranged in the central space 40 of the doughnut-shaped inner tube connecting device 35.

Preheated ore and 7 lacs were mixed with coal and coke in the following ratio into the rotary converter configured as above, and the mixture was charged into the furnace through the raw material charging port 16. ○Cr ore: 190
01, burnt lime: 254k, silica: 26-1 iron slag: 5k, coal: 4004. Coke: 400-0 Next, at the same time oxygen is blown from the blowing oxygen injection lance 21, the space part (range B!l) and metal, slag raw H
, A mixture of pulverized coal and water is flowed from the outer pipe 18 of the small hole 14 in the part (range A), and a mixture of water is flowed from the inner pipe 18 & to promote the dissolution of the raw materials. After about 20 minutes, the raw material melted and the slag temperature reached #1600°C, at which point additional coke was added at 300 °C and pulverized coal was added from treatment 18 of the metal and slag generation part (MUO S). Water of & compounds,
Water is flowed from the inner pipe 18 &, and n water vapor t 11 L is flowed from the outer pipe 18 and the inner pipe 18m of the space part (range 1!i of B), respectively.
Approximately 55 minutes after the start of 7t o ml slag 1a
ta reached about 1730°C.The amount of metal produced at this time was about 980If, and the metal assembly was 5A6*Cr,a
5 fkc, 57.2% Fe.

Furthermore, in the trench where the smelting ends from this point, the outer pipe 18 of the small hole 14 in the metal and slag generation part (range 8 of the metal) is removed.
Ar + 01 gas is added to the inner pipe 1Bm + (h + water'
Drain the outer tube 18 and inner tube 18 of the empty part (B range III). Steam was applied to each of the baths, and the blowing was completed in about 75 minutes, and the hot water was poured out. At this time, the amount of metal, slag, and chemical total or each is excessive.

Metal Dou: 94011 Chemical composition: 53.2%Cr, 7.4%C136,51G
Fa, 1.0%Si slag noble: 125Q ceramic composition 1.5%CrzOs, 17IIi810
x, 28%CaO, 2816At richness 0. ．． 2511Mg
0 w, Figure 11 shows the elapsed time, gas injection amount, metal production amount, raw material slag temperature, and lI! in the above example. FIG. 11 is a diagram showing the relationship with the amount of bare blowing.

In the above description, the case where a specific gas is blown through a small hole provided in the furnace body is described, but the present invention can use the gas in the volume shown in Table 1. In addition, although an example of manufacturing ferrochrome has been described, the present invention can also be applied to the manufacture of other metals to achieve similar effects.Furthermore, the furnace body is equipped with a small hole and a connection between the scum source and the like. An example is No. 450. Although shown in FIGS. 9 and 10, the present invention is not limited thereto, and other means may be used as long as they perform similar functions. According to the invention, the following effects can be achieved. (υ) It is possible to use coke, which is cheap and has a stable supply. Since the surface of the object is cooled, the lifespan of the refractory can be extended by a EEC.
This reduces repair costs and reduces loss time for repairs.(3) Fuel and bulk are injected through small holes to promote melting of raw materials, reducing blowing time. (4) It is possible to decarburize the processed metal, for example, from 7 to
From 8% C high carbon 7 erochrome, 3 to 4 g 6C medium R grade ferrochrome is now possible c

[Brief explanation of the drawing]

Island 1 is an example of a conventional rotary furnace! 1 and 2 are vertical sectional views of the rotary furnace according to the present invention, and FIG.
(c) Vertical cross-sectional view showing an embodiment of small holes provided in the furnace body, and Figure 5 is a vertical cross-sectional view of an embodiment of the present invention. Figure 6 is the BB sectional view, W41W
JA line A diagram showing the relationship between the passage of time and each element according to the present invention and examples, Jl! Figure 8 is a longitudinal sectional view of another embodiment of the present invention, Figure 9 (a), ridges (.), and Figures 1υ (a), (c) are double pipes of the above embodiment. FIG. 11 is a side view and an exploded plan view showing an example of the connection between the device and the waste source, and FIG. 11 is a diagram showing the relationship between each element over time in another embodiment of the present invention. 10: Furnace body, 11: Iron shell, 12: Refractory, 14: Small hole,
19.20: Gas connecting pipe, 21: Blowing oxygen injection lance, 60: Outer pipe connecting device, 65: Inner pipe connecting device. Agent: Patent Attorney Tadashi Sato Figure 7 Figure 8

Claims (4)

[Claims] (1) A metal alloy characterized in that the furnace body is provided with several small gas injection holes or small holes filled with porous refractory that penetrate through the iron shell and refractory to open the furnace PgK. fII
11 horizontal or sloped bed 1 converter 0 for fist reduction or refining (2) The furnace body is provided with a plurality of small gas injection holes that penetrate the steel shell and refractories and open into the furnace, or are filled with porous refractories and have small holes filled with metal and flux. A metal alloy 0@melting reduction or refining characterized in that a cooling medium such as air is blown into the small hole in the upper part that is not in contact with the bath and the reducing agent to prevent overheating of the refractory lined with the circle WJK of the furnace. -11 Arrival is slope I! Rotary furnace〇 (3) Fill the furnace body with several small holes for gas injection that penetrate the shell and refractories and open into the furnace, or fill with porous refractories and provide small dew holes, and charge into the furnace Pg. Before raw materials such as good ore 75x are dissolved, fuel or fuel is used to promote dissolution. After the raw materials have been melted, the following materials are blown into the mixture, and during the reduction period after the raw materials are melted, cooling gas is supplied from the upper space to oxidize the raw materials in the metal that is produced, and from the lower metal and slag raw bottom part. A rotary furnace characterized by blowing oxidizing gas. (4) A plurality of small holes for gas injection or small holes filled with porous refractory material are provided in the furnace body to penetrate through the steel skin and refractories and open into the furnace, and the small holes are formed into a double pipe structure. During the melting stage of the raw materials charged into the furnace, fuel is injected from the outer tube containing oxygen from the PM double pipe to promote melting, and during the reducing stage of the raw materials, metal and slag are A rotary furnace characterized in that carbon in the metal is decarburized by injecting an oxidizing gas such as elemental gas from the inner pipe into the production part and a cooling gas such as argon from the outer pipe.