National service hotline:
186 0120 9822
186 0120 9822
news center
Contact us
Sales Hotline:


Technical Service:

Company address:

Changshun town industrial park in ulanqab, Inner Mongolia autonomous region

current location:home > news centernews center

Smelting process design of high carbon ferrochrome

from: | update:2019-10-19 | font:small-middle-big | views293

First, the mine furnace
The production method of high carbon ferrochrome is an electric furnace method, a shaft furnace (blast furnace) method, a plasma method, and a smelting reduction method. The shaft furnace method now only produces low
The shaft furnace production process of chromium alloy (Cr<30%) and higher chromium content (eg Cr>60%) is still in the research stage; the latter two methods are emerging processes under exploration; therefore, the vast majority Commercial high-carbon ferrochrome and re-formed ferrochrome are produced by electric furnace (mineral furnace). Electric furnace smelting has the following characteristics:
(1) Electric stoves use electricity as the cleanest energy source. Other energy sources such as coal, coke, crude oil, natural gas, etc. will inevitably be associated
The impurity elements are brought into the metallurgical process. Only the electric furnace can be used to produce the cleanest alloy.
(2) Electricity is the only energy source that can obtain any high temperature conditions.
(3) The electric furnace is easy to realize thermodynamic conditions such as oxygen partial pressure and nitrogen partial pressure required for various metallurgical reactions such as reduction, refining, and nitriding.

Second, the process
1. Selection of raw materials
The raw materials for smelting high carbon soldering iron are chrome ore, coke and silica. Among them, coke and silica are used as reducing agents.
(1) chrome ore
The world chromite deposits are mainly distributed in the Great Rift Valley in the East Africa, the Ural Belt in the Eurasian Mountains, the Alpine-Himalayan Belt and
Pacific Rim Belt. The amount of chromite ore in the near-north-north fold belt accounts for more than 90% of the world total. Among them, South Africa, Kazakhstan and Zimbabwe account for more than 85% of the world\\\'s proven total chromite reserves, accounting for more than 90% of the reserves, and South Africa alone accounts for about 3/4 of the reserves.
1 Beneficiation principle: Since chromium is the most used metal, it ranks first in the “strategic metal”. The world today has chrome resources
Countries or countries with scarce resources are stepping up research on chrome ore beneficiation. The selection methods are:
1) Re-election: such as jigging, shaker, spiral chute, heavy medium cyclone, etc.

2) Magnetic power selection: including high-strength field magnetic separation and high-voltage electric selection.

3) Flotation and flocculation flotation.

4) Joint selection: such as re-election - electrification.

5) Chemical beneficiation: It is difficult to treat chrome-poor ore in the treatment of very fine particles.
In the above-mentioned chrome ore beneficiation method, the re-election method is mainly used in production, and the shaker and the jig are often used for sorting. Sometimes re-selection of concentrates is weak
Re-election or strong magnetic separation to further improve the grade of chrome ore and ferrochrome ratio.
2 chrome ore matching principle: In the actual production of high carbon ferrochrome, it is often necessary to select the appropriate mineral mix and proportion. Chrome ore
The main principles of distribution are:
1) A suitable ferrochrome ratio (Cr2o3/∑FeO). In general, smelting alloys containing more than 50% chromium requires furnaces to be integrated into the mine.
The Cr2o3/∑FeO ratio is greater than 2.0; and alloys containing more than 60% chromium are required to have a ratio greater than 2.6.
2) A suitable MgO/Al2o3 ratio. It not only affects the electrical conductivity and reduction properties of the slag, but also affects the carbon-containing disk of the alloy.
In actual production, MgO/Al2o3 is used, and the chromium ore with a lower ratio needs to be mixed with sufficient coke to increase the thickness of the coke layer, on the one hand to ensure that the furnace bottom is not easily damaged, and on the other hand to increase the unreduced ore core. The residence time in the coke layer. Reduce chrome running in the slag.
3) Proper block matching. When the powder ore is used alone, it is easy to cause the sintering of the fine ore, which deteriorates the gas permeability of the material surface and seriously destroys the smelting gas.
Atmosphere; the use of chrome ore with a large block size tends to increase the thickness of the refining layer, resulting in a low carbon content of the alloy.
4) Suitable melting properties. The simple use of fusible chrome ore will cause premature slag formation, making the melting rate faster than the reduction rate, which is easy to cause slag.
The phenomenon of running chrome is high; the simple use of refractory chrome ore will thicken the refining layer, and there will be a large number of unreduced ore cores and low carbon content of the alloy, which brings great difficulties to normal smelting. Reasonable matching of chrome ore makes slag have a reasonable melting point, which is very important for improving economic indicators.
(2) reducing agent
In the production of alloys, the most common one is the cheapest reducing agent - metallurgical coke \\\"crush\\\" (screened coke after blast furnace coke screening). Due to the quality of coal for coking and the conditions for producing coke in the coking plant, the quality of the coke block is also different. However, they have a common disadvantage, that is, the resistance is not high, the reaction performance is poor, the ash content and the sulfur and phosphorus content are high, and the moisture content is also high, and it is unstable.
The sulfur contained in coke is mainly organic hydrazine and a large amount of sulphide, and a small amount of sulphate and a very small amount of solid solution in carbon
In the element sulfur. The phosphorus content of coke is also different. The coke block has a spongy structure and a large number of cracks, and the porosity thereof fluctuates within the range of 35% to 55%, and the apparent density of coke is 0.8-1 t/m3.

1 Beneficiation principle: Since chromium is the most used metal, it ranks first in the “strategic metal”. The world today has chrome resources
Countries or countries with scarce resources are stepping up research on chrome ore beneficiation. The selection methods are:
1) Re-election: such as jigging, shaker, spiral chute, heavy medium cyclone, etc.

2) Magnetic power selection: including high-strength field magnetic separation and high-voltage electric selection.

3) Flotation and flocculation flotation.

4) Joint selection: such as re-election - electrification.

5) Chemical beneficiation: It is difficult to treat chrome-poor ore in the treatment of very fine particles.
In the above-mentioned chrome ore beneficiation method, the re-election method is mainly used in production, and the shaker and the jig are often used for sorting. Sometimes re-selection of concentrates is weak
Re-election or strong magnetic separation to further improve the grade of chrome ore and ferrochrome ratio.
2 chrome ore matching principle: In the actual production of high carbon ferrochrome, it is often necessary to select the appropriate mineral mix and proportion. Chrome ore
The main principles of distribution are:
1) A suitable ferrochrome ratio (Cr2o3/∑FeO). In general, smelting alloys containing more than 50% chromium requires furnaces to be integrated into the mine.
The Cr2o3/∑FeO ratio is greater than 2.0; and alloys containing more than 60% chromium are required to have a ratio greater than 2.6.
2) A suitable MgO/Al2o3 ratio. It not only affects the electrical conductivity and reduction properties of the slag, but also affects the carbon-containing disk of the alloy.
In actual production, MgO/Al2o3 is used, and the chromium ore with a lower ratio needs to be mixed with sufficient coke to increase the thickness of the coke layer, on the one hand to ensure that the furnace bottom is not easily damaged, and on the other hand to increase the unreduced ore core. The residence time in the coke layer. Reduce chrome running in the slag.
3) Proper block matching. When the powder ore is used alone, it is easy to cause the sintering of the fine ore, which deteriorates the gas permeability of the material surface and seriously destroys the smelting gas.
Atmosphere; the use of chrome ore with a large block size tends to increase the thickness of the refining layer, resulting in a low carbon content of the alloy.
4) Suitable melting properties. The simple use of fusible chrome ore will cause premature slag formation, making the melting rate faster than the reduction rate, which is easy to cause slag.
The phenomenon of running chrome is high; the simple use of refractory chrome ore will thicken the refining layer, and there will be a large number of unreduced ore cores and low carbon content of the alloy, which brings great difficulties to normal smelting. Reasonable matching of chrome ore makes slag have a reasonable melting point, which is very important for improving economic indicators.
(2) reducing agent
In the production of alloys, the most common one is the cheapest reducing agent - metallurgical coke \\\"crush\\\" (screened coke after blast furnace coke screening). Due to the quality of coal for coking and the conditions for producing coke in the coking plant, the quality of the coke block is also different. However, they have a common disadvantage, that is, the resistance is not high, the reaction performance is poor, the ash content and the sulfur and phosphorus content are high, and the moisture content is also high, and it is unstable.
The sulfur contained in coke is mainly organic hydrazine and a large amount of sulphide, and a small amount of sulphate and a very small amount of solid solution in carbon
In the element sulfur. The phosphorus content of coke is also different. The coke block has a spongy structure and a large number of cracks, and the porosity thereof fluctuates within the range of 35% to 55%, and the apparent density of coke is 0.8-1 t/m3.





Reprint statement:
The article is reproduced on the Internet for the purpose of transmitting more information and does not imply endorsement of its views or verification of the authenticity of its content. If the reprinted works infringe the author\\\'s right to authorize, or have other damages such as copyright, portrait rights, intellectual property rights, etc., this website is not intentionally made and will be corrected immediately upon notification by the relevant right holder.



Copy right: Inner Mongolia Rishengzhibo metallurgical limited liability company Copyright 2017
Add::Changshun town industrial park in ulanqab, Inner Mongolia autonomous region
Tel:186 0120 9822
Web::www.
   

Scan qr code
Enter mobile phone station

海南体彩网-首页

    <kbd id="rwtdf" ></kbd>
  1. <video id="rwtdf" ><big id="rwtdf" ><xmp id="rwtdf" >
  2. <rp id="rwtdf" ></rp>

    <var id="rwtdf" ></var>

    <pre id="rwtdf" ><video id="rwtdf" ></video></pre>
    <nobr id="rwtdf" ></nobr>