Use in open-hearth roofs of periclase-chromite parts made from electrofused periclase-chromite

Conclusions A production test was made in the roof of a 180-ton open hearth of periclase-chromite parts produced by the Magnesite Combine from electrofused periclase-chromite.The life of the roof of experimental parts was an average of two campaigns of 690 heats, which is three times longer than the life of PKhS refractories produced by the Nizhnii Tagil Metallurgical Combine.The difference in the life of the two forms of refractories may be explained by features of their phase composition, structure, and failure mechanism.It was shown that the main improvement in the quality of the refractories is a significant reserve for increasing the life of open hearth roofs. The use in open hearth roofs of parts of electrofused periclase-chromite makes it possible to decrease the refractory consumption by 3.36 kg per ton of steel and to reduce the cost of a ton of steel by 0.05 rubles.It is necessary to continue work in the direction of production and use of refractories of pure sintered and fused original materials, especially in the local areas subject to the maximum wear of the roofs of open hearths in which high quality steel is melted.Translated from Ogneupory, No. 7, pp. 45–50, July, 1985.     

The profit and profitability indices of refractories production

Conclusions During the period 1966–1970 the profit level at refractory establishments increased while the profitability and fund redemption indices fell slightly. On the whole, however, the production profitability at these establishments is adequate and higher than the norm fixed for them by the Ministry.In view of the steep increase in the ouptut of high-quality refractories the efficiency with which refractory establishments utilize expended means and means on loan must be evaluated with account taken of the savings accruing to consumers of refractories from the use of better-quality refractory materials.To improve the economic indices of refractory establishments it will be necessary to devise and introduce certain measures.To stimulate the interest of establishments in the production of better refractories efforts must be continued to modify the prices ratio for the product and raw materials for certain types and groups of refractories, i. e., to increase the profitability of high-quality refractories at the cost of slightly lower prices for lower-grade refractory materials. The profitability level of winning and beneficiating refractory raw materials must be raised.Translated from Ogneupory, No. 3, pp. 16–20, March, 1976.     

浅析红土镍矿回转窑整体窑炉技术的施工与应用

回转窑内衬可用耐火砖砌筑,也可选用其它的耐火材料做内衬,但是近几年,随着施工方法的改进及耐火材料研发的突破,回转窑内衬开始选用整体窑炉技术。将回转窑内衬的材料选用及施工工艺相结合,此方法可以提高回转窑产能,减少热损失,取得了高效节能降耗的显著效果。     

An Electronic Technology for Refractories Based on the Periodic Law

Prospects for development of electronic technologies in the production of refractories are discussed. Principles of the electron technology of refractories are given and techniques for control of electron supply in the electrochemical, thermochemical, and electrothermochemical treatment of refractory materials are described. The potential use of electromagnetic fields to increase the slag resistance of refractory linings is considered. Electronic wear as an initial stage in the wear of refractory materials is considered. Decreasing the diffusion of electrons from metal and slag to refractory may inhibit the electronic wear of refractory lining. Interested readers are invited to take part in a discussion of the material of this paper. __________ Translated from Novye Ogneupory, No. 10, pp. 75 – 83, October, 2005.     

Wear of Basic Refractories in the Lining of Waelz Kilns in the Production of Zinc

Operating conditions of the refractory lining for Waeltz kilns in the production of zinc are considered. Results of an examination of post-service periclase-spinellide refractories for the Waelz kiln lining are given and major factors involved in the wear and failure of refractory materials are discussed.     

Baddeleyite-corundum refractories for the glass industry

Products of the Shcherbinskii plant of electromelting refractories are characterized. Baddeleyite-corundum articles and unshaped materials are used for lining and erecting glass-melting furnaces. The concept of the development of the production of molten-cast refractories in the plant is presented. Ways of diminishing the cost of the products and raising the efficiency of use of refractories by consumers are considered.     

Use of unfired periclase-carbon refractories in parts of linings of 350-ton steel-teeming ladles

Workers of the Azovstal’Company have established the causes of the decrease in the endurance of slag-line areas of linings of 350-ton steel-teeming ladles. In 1995–1996 they conducted industrial tests and introduced a process for lining the slag areas of 350-ton teeming ladles with unfired periclase-carbon refractories. The mean service life of a lining of a 350-ton teeming ladle with a slag line made of periclase-carbon refractories amounts to 23 heats on the average without hot repairs of the slag line during the campaign. The wear of the periclase-carbon lining in the slag line is 3.6–4.3 mm per heat. The specific consumption of refractories and materials for a lining has been decreased by 0.6–0.8 kg per ton of converter steel. Such an operating capacity for the periclase-carbon refractories in slag lines is provided by the composition and structure of the refractories, which possess a high heat resistance and resist the effect of the molten metal and slag. Translated from Ogneupory i Tekhnicheskaya Keramika, No. 2, pp. 37–39, February, 1998.     

New Gruppa Magnezit chromite-periclase refractories for a Zinc production Waelz kiln

Results of research work performed by Gruppa Magnezit are provided for prolonging the campaign of a zinc production Waelz kiln. Research into the corrosion resistance of refractory objects by a charge, consisting of ore and coke, is used to select the substance composition and development of technology for chromite-periclase refractory production that is inert towards Waelz material components. Service tests show that use of new refractories within the reaction zone of aWaelz kiln lining provides stable performance for the production process with high productivity and an increase in the time between repairs.     

Experience in the use of periclase—Carbon refractories in the working lining of a steel converter

The causes of the impairment in the durability of the converter lining at the Azovstal’Integrated Iron and Steel Works were identified. In April–June 1997, commercial-scale tests were carried out on periclase–carbon refractories of grades LIUBX-15 and LIUBXZ-710 used in the working lining of a converter. The lining withstood 1025 heats. From the beginning of 1997, the average durability of the converter lining fabricated from commercial unburned periclase—limestone refractories of grade PIBS-50 was 475 heats. The improvement in durability was due to the use of periclase—carbon refractories containing 10 to 20% carbon. The nominal service life of grade LIUBX-15 and LIUBXZ-710 periclase—carbon refractories under the conditions obtaining at the converter plant of the Azovstal' Integrated Iron and Steel Works is 1200 to 1300 heats. With the documented durability of 1025 heats, the use of periclase—carbon refractories in the working lining of the converter thus cuts the cost of the lining by as much as US $0.3 per metric ton of converter steel.     

Quality and economy of refractories

Conclusions The development of new forms of refractories must be based on the use of all forms of raw material, including the lowest grades. Beneficiation of raw material must be done for a purpose and be based on technical necessity, cost effectiveness, and ecological desirability.It is necessary to develop at accelerated rates the production of unformed and unfired refractories and to locate it preferentially in plants producing fireclays and having avilable various forms of inexpensive raw material.Newly created methods must answer the requirements of production of high quality parts, full mechanization, provision of atmospheric cleanliness, and cost effectiveness in the production and use of them.Investigators and production personnel must concentrate their attention on the solution of problems of a sharp decrease or the elimination of formation of dust in firing raw materials in rotating kilns and effective utilization of the dust caught in refractory production.Scientific-research institutes together with production plants and design organizations must develop and use modern instruments and on the basis of them develop new accelerated and automated methods of quality inspection of semifinished products and finished refractory production (chemical and phase composition, nondestructive methods for determining the physicomechanical, thermophysical, and other properties).Extending the service life of lining under the action of slag, metal, a gaseous medium, and thermal impacts must be done by guniting, cooling of the lining and refractory parts with air, water, and steam, and the introduction of new lining designs.Translated from Ogneupory, No. 7, pp. 4–9, July, 1982.     

Use of magnesite refractories in the chequerwork of the air heaters of blast furnaces

Conclusions Magnesite refractories are a promising material for use in the upper rows of the chequerwork, particularly where it is necessary to increase the thermal capacity of the air heaters without increasing their dimensions.When the magnesite refractories are used, the mass of the chequerwork and the unit load on the subchequerwork grid and the lower rows of the chequerwork are increased.The improved efficiency of magnesite refractories in the chequework of air-heaters by comparison with other types of refractory is becouse of their high storage capacity for heat as a result of the increased apparent density and better thermophysical characteristics.The magnesite refractory used in the chequerwork should contain a minimal amount of impurities, particularly of Fe₂O₃.When magnesite refractories are used to replace dinas, the cost per ton of chequerwork increases 50% while for the replacement of mullite by magnesite, the cost per ton of chequerwork is reduced by 16%.Contact between the magnesite refractories and the dinas (without a load) is permissible at a temperature not higher than 1450°C; with sillimanite, at not more than 1350°C.In order to prevent the action of finely dispersed particles of dust and alkali oxides accidentally introduced into the air heaters it is sensible for the upper row of chequerwork to be made from sillimanite or mullite refractories.The theoretical extreme temperature for the use of magnesite refractories in the chequerwork of the air heaters (allowing for creep and the interaction with other types of refractories) is 1650°C for M-I type blocks and for M-II, not more than 1450°C. For greater safety it is recommended that the ultimate working temperatures be reduced by 150°C.Taking into account the favorable experience abroad in using magnesite blocks in the chequerwork of air heaters, it is necessary to carry out industrial tests of the magnesite products in the upper zones of the chequerwork.Translated from Ogneupory, No. 7, pp. 32–36, July, 1982.     

Key Technologies for Energy Efficient Al(OH)_3 Dilute Phase Fluidized Bed Roasting Furnaces

Research on new types of castables, pre-cast assembly parts and thermal insulation materials with good resistance to wear, thermal shock and erosion, and low thermal conductivity, was done to solve problems of high system energy consumption, cracking and spalling of partial lining and mismatch of furnace top material and hanging material and so on, caused by unreasonable design of China's Al(OH)3 dilute phase fluidized bed roasting furnace lining. Several difficult problems such as the matching of different materials, preservation of expansion joints among different zones and reasonable mechanical distribution of lining were solved. "Integrated furnace" concept was established including refractories R D, lining structure design, construction optimization, furnace warming technology, initial operation and lining maintenance technology. The key technologies of high-efficiency and energy-saving for furnaces were developed. These achievements have been applied to China's Al(OH)3 dilute phase fluidized bed roasting furnaces to reduce energy consumption by 1 000 MJ per ton alumina, enhance the capacity and reduce the exhaust gas emission.     

Tests of refractories in argon-oxygen refining of metal

Conclusions As the result of comparative tests of refractories of different forms in the lining of the cylindrical portion of a 10-ton converter using argon-oxygen refining it was established that the most resistant of the tested materials is the periclase-spinellide refractory with the addition of chrome-alumina-spinellide. These parts may be recommended for lining the cylindrical portion of a pilot production argon-oxygen refining unit.Translated from Ogneupory, No. 5, pp. 42–46, May, 1987.     

铜精炼阳极炉用镁-铬耐火材料内衬的气相腐蚀

镁铬耐火材料是铜精炼阳极炉风口常用的耐火材料。除热化学和热机械损耗之外，内衬还要经受气相腐蚀损坏。这里介绍了在伊朗Sarcheshmeh制铜集团（complex）的阳极炉中气相腐蚀的研究结果。由XRD和SEM/EDX对用后的铬镁耐火砖进行了分析。结果表明：在温度约900℃时，耐火内衬因碳沉积而开始破坏。由于耐火材料中含有铁相而使耐火材料的气孔中碳沉淀更加严重。然而对于低铁的铬镁耐火内衬，这种腐蚀将是轻微的。对于尖晶石类耐火材料，未观察到内衬破坏。从实用和经济的观点对阳极炉内衬的上述结果进行了讨论。     

不定形耐火浇注料在我公司沸腾炉中的应用

硫酸生产中 ,沸腾炉耐火衬里传统采用耐火砖砌筑 ,施工和检修相对较麻烦 ,费用也较高。通过对不定形耐火浇注料的性能测试 ,在炉顶球拱采用高铝质超低水泥耐火浇注料使用成功的基础上 ,进而用于沸腾炉炉体内衬获得成功。介绍了炉顶球拱和炉体内衬采用不定形耐火浇注料的施工方法 ,认为该技术先进可靠、投资适中、经济适用 ,有广泛的应用前景     

建材窑炉用耐火材料“八五”攻关成绩显著,硕果累累

本文概述了中国建材院耐火所承担和组织和建材工业窑炉用耐火材料“八五”国家重点科技攻关项目，在优势耐火原料合成技术，研制先进的耐火装备以及耐火材料的新品种２，新工艺方面取得的丰硕成果。     

Magnesia nozzles for high-speed steelcasting produced by vibropressure molding

Conclusions The article describes the design development of steelcasting nozzles with a channel diameter of 120 mm and the development of the production technology for these nozzles. With these nozzles the stopper and batching device functions efficiently during the casting of rimmed and semikilled steel. The configuration and diameter of the nozzle channel undergo no changes in the process.The increase in the channel diameter from 100 to 120 mm results in the average linear speed at which the ingot mold is filled increasing from 3.8 to 5.2 m/min; in a decrease by 32% in the pouring time per melt (from 25 to 17 min) so that the work load on the cranes is reduced and the handling capacity of the casting bay is increased; in a 15% increase in the durability of the ladle lining which gives a saving of 100,000 rubles/yr as a result of lower refractories consumption; and in less spoilage of billets and strip steel.The end result is that the net cost of the rolled product decreases by 0.35 ruble/ton.Translated from Ogneupory, No. 3, pp. 6–13, March, 1978.     

Comprehensive solution for lining the socle of an electrolyzer with contemporary refractories and heat insulating materials

OAO Borovichi Refractory Plant has developed a number of new forms of product for lining the socle of an electrolyzer for obtaining primary aluminium. Results are provided for research on thermal insulating vermiculite products of the ITOM (integral heat insulation refractory materials) series and barrier materials: dense fired refractory articles BorAluBar, mastic for filling joints BorAluPlast, and dry barrier mixture BorAluMix. Newly developed products will make it possible to propose to aluminum producers a comprehensive solution for lining the electrolyzer cathode with contemporary refractories and thermal insulating materials with a high technical resource. Use of the materials will make it possible to prolong electrolyzer service life by several degrees. __________ Translated from Novye Ogneupory, No. 3, pp. 99–107, March, 2007.     

Increasing the resistance of oxygen converter linings

Conclusions We developed a. differentiated construction for converter linings using tarred dolomite and periclase — spinel refractories in sites most prone to erosion: the throat, the neck, and the upper cylindrical parts on the pivot sides. Taking into account the topography of the wear we selected a rational profile for the working layer of the lining with which we obtained a higher and more uniform resistance.We developed and introduced a production technology for tarred dolomite refractories by pressingbodies cooled to 35–45°C, using tar with an increased coke residue and a viscosity of C¹⁰ ₄₀=40-50 sec as the bond.We also improved the order of feeding in the batch materials, introduced slag and blow cycles for converter melting, ensuring rapid finishing of the high-basic slag in the blow process, reducing the melting time and the number of heats produced with the blow, etc.As a result of improving the quality of the tarred dolomite refractories, the introduction of the differentiated (with respect to thickness and types of refractories used) constructions for the linings, the use of rational firing cycles for the linings, improvements and stabilization in the quality of the batch materials, and improvements in the converter melting technology, the average life of the converter linings increased to 612 heats and the total consumption of refractories dropped to 2.95 kg/ton of steel; the maximum resistance reached 646 heats.The increase in the life of the linings ensured regular operation of the converter shop and provided a substantial increase in steel output.Translated from Ogneupory, No. 1, pp. 5–11, January, 1970.