轻烧镁球烧结降镁，效益更美 Light-burned magnesium balls sinter magnesium reduction, more beautiful
发布日期：2016-04-25 00:00 来源：http://www.ykbhlm.com 点击：
In recent years, the situation of the iron and steel industry has been severe, the cost pressure before iron has increased sharply, and the quality of iron ore powder has continued to deteriorate. In order to stabilize the quality of the sintered ore and further reduce the cost of ironmaking, after a series of basic research, Shougang Jingtang Company has finally achieved natural magnesium sintering. The sintered ore grade, strength, particle size, metallurgical properties and droplet properties have been improved and created Considerable economic benefits.
优势 Light-burned magnesium sintering has obvious advantages in reducing magnesium
As the main charge of blast furnaces in the Asia-Pacific region, sinter ore generally accounts for more than 60% of the blast furnace structure. Usually dolomite, serpentine and other magnesium-containing fluxes are added to the sintering batch to increase the MgO content in the blast furnace slag to improve the fluidity and desulfurization ability of the slag and adapt to the high Al2O3 mass fraction in the slag.
Rhenium sintering is the main source of blast furnace slag MgO, and its MgO content is limited by blast furnace slag demand and blast furnace operating habits. The content of MgO in blast furnace slag from Japan and South Korea is controlled at the level of 3% to 5%, while most of them are above 7% in China. Affected by this, the MgO content of Japan's Nippon Steel, South Korea's Pohang Gwangyang, and Hyundai Iron Sinter is between 0.7% and 1.2%; while the MgO content of domestic sinters is mostly above 1.6%, which is even higher than 3.0. %the above. Some researchers even believe that the higher MgO content in sintering is conducive to improving the quality of sintered ore.
In recent years, a large number of domestic light-burned magnesium ball sintering researchers have called for light-burned magnesium ball sintering to reduce magnesium, and Shougang Jingtang has taken the lead in practice. The project team carried out a series of sintering MgO laboratory researches on sintering process thermal balance calculation, sintering basic characteristics test and high-temperature confocal in-situ observation, ore phase research, sintering cup test, comprehensive furnace melt droplet performance test around Shougang Jingtang.
The study found:
Magnesium reduction helps to improve the grade of sinter ore, helps to develop high-quality calcium ferrite, and improves the reducibility of sinter ore. Reducing the MgO by 0.5% can increase the TFe content of the sintered ore by more than 0.3%. Against the background of the deterioration of imported ore powder, adjusting magnesium has more value in actively maintaining the sintering ore grade. Increasing the grade of sinter ore will help to form more high-quality binding phases-acicular calcium ferrite, which is beneficial to improving the sinter ore index and reducing property.
Magnesium reduction helps to reduce the heat consumption of the flux, thereby increasing the effective heat of sintering. Magnesium-containing flux decomposes and consumes heat during the sintering process. Reducing the proportion of magnesium-containing flux helps to save energy and improve the quality of sintered ore. The sintered ore MgO content is reduced by 0.5 percentage points, the unit consumption of magnesium-containing flux is reduced by 14kg / t sintered ore, and the decomposition heat consumption during the sintering process is reduced by about 1%, which is equivalent to an increase in the effective heat of the sintering process with a certain sintering heat loss %, Which is conducive to the improvement of the particle size composition of the sinter.
Magnesium reduction helps to improve the liquidity of the sintering liquid phase and enhance the sintering bonding effect. The basic characteristics of sintering and high-temperature confocal equipment tests showed that: after reducing the MgO content of the sintered mix from 2.3% to 0.3%, the liquidity index increased from 0.7 to 1.9; compared with the solution containing MgO, in-situ observation found no The MgO-containing solution has the highest liquid flow rate. The improvement of the liquidity of the sintered liquid phase enhances the bonding effect and is beneficial to the improvement of the particle size composition of the sintered ore.
Sintering magnesium reduction and pelletizing magnesium extraction, on the basis of ensuring the stability of the blast furnace slag system, improved the melt droplet performance of the comprehensive charge. Droplet performance tests show that after the overall charge structure is changed from sintered ore 1.9% MgO + pellets 0.7% MgO to sintered ore 1.5% MgO + pellets 1.7% MgO, the droplet interval is reduced from 64 ° C to 59 ° C, the maximum pressure difference From 1910Pa to 1590Pa, the S characteristic value of the comprehensive charge is finally reduced from 122.2kPa · ° C to 93.8kPa · ° C.
Industrial practice creates benefits
Basic research found that the advantages of light-burned magnesium balls for sintering magnesium are obvious. In November 2012, Shougang Jingtang pellets produced magnesium pellets, which provided conditions for sintering magnesium reduction. In February 2013, researchers began an industrial test of reducing MgO at Shougang Jingtang Sintering, and achieved the following results: The sintered ore MgO content gradually decreased from 1.8% to 1.5%, combined with the ore powder structure adjustment, the sintered ore grade was 55.95% It increased to 56.48%. After September 2013, magnesium-containing flux had been basically stopped in Shougang Jingtang. After magnesium reduction, the sintering index improved significantly: the proportion of sintered ore <10mm decreased from 20.28% to 17.85%, the reducibility increased from 80.15% to 84.7%, the droplet properties of sintered ore improved significantly, and the S characteristic value of sintered ore decreased from 262kPa To 87kPa · ° C. The main indicators of Shougang Jingtang Sinter in recent years are shown in the attached table.
After more than one year of industrial practice, MgO content of Shougang Jingtang Sinter has stabilized at the level of 1.4% to 1.5% in 2014, the lowest level among large domestic sinter plants, and it reached 1.35% in October 2014.
The picture shows the comparison of MgO content between Shougang Jingtang Sintering Plant and international sintering plants. Compared with some international advanced factories and mines, although the MgO content of Shougang Jingtang sinter is still slightly higher, it is already a natural magnesium sinter with no magnesium-containing flux.
统计 According to statistics, Shougang Jingtang's annual sintering magnesium reduction reached 8.125 million yuan. In October 2014, after expert appraisal, Shougang Jingtang sintering magnesium reduction research and practice reached the domestic leading level.
Experts believe that the successful practice of Shougang Jingtang sintering magnesium reduction has great application prospects in China. Iron and steel enterprises can consider the following two application schemes: one is to reduce the MgO content of the sintered ore to appropriately reduce the MgO content in the blast furnace slag to contribute to the blast furnace concentrate; the second is to reduce the proportion of the sintered magnesium-containing flux, correspondingly in the ball Appropriate magnesium-containing additives are added to the pellets--the MgO content of the sintered ore is transferred to the pellets, and the metallurgical and molten droplet properties of the comprehensive charge are improved by producing low-magnesium sintered ore and high-magnesium pellets, thereby improving the technical and economic indicators of the blast furnace .
- 购买轻烧镁球后，要采取保护措施 Protective measures should be taken after purchasing lightly burned magnesium balls
- 炼钢废弃料制轻烧镁球工艺 Process for making light-burned magnesium balls from steelmaking waste
- 转变经济发展 加强企业创新 轻烧镁球资源高效合理利用
- 轻烧镁球如何在溅渣中护炉 How lightly burned magnesium balls protect the furnace in slag splashing
- 轻烧镁球含有什么成分 What is the content of lightly burned magnesium balls
- 优质转炉终渣轻烧镁球生产直销 Production and sales of high-quality converter final slag light-burned magnesium balls
- 轻烧镁球如何在溅渣中护炉 How lightly burned magnesium balls protect the furnace in slag splashing
- 轻烧镁球行业的明天 The future of light burned magnesium ball industry
- 供应优质轻烧镁球 Supply of high quality light burned magnesium balls
- 转变经济发展 加强企业创新 轻烧镁球资源高效合理利用 Transforming economic development, strengthening corporate innovation, efficient and rational use of light-burned magnesium balls