Open-hearth Slag Research Articles

Hydraulic activity of crushing screenings of waste open-hearth slag

Theoretically and experimentally studied the hydraulic activity of crushing screenings of waste open-hearth slag and methods for intensifying the hydration hardening of slag stone during operation. During the hardening of slag stone, three periods of pronounced syneresis with gel new formations strengthening the material were established at the ages of 28 – 60, 90 – 180 days and 1 – 2 years. The first period of syneresis, in contrast to the subsequent ones without changing the strength of the samples, is recorded by the linear shrinkage of the samples, the squeezing out of bound water and the increase in pH. The introduction of two percent of cement dust or lime into the crushing screenings of waste open-hearth slag leads to the strengthening of the slag stone at 28 and 90 days of age by 3 – 4 times. However, by the age of two years, the strength of the samples stabilizes. This fact indicates that the additions of cement dust or lime are not additional binders, but hardening accelerators.

Granulation of open-hearth slag in conditions of reducing anthropogenic load on the environment

Granulation of open-hearth slag in conditions of reducing anthropogenic load on the environment

Preparation of Adsorbents by Pyrolysis of Sludge Mixed With Steel Slag and Study on Adsorption of Chromium Ions in Water

In this study, the dewatered sludge from the sewage plant and the open-hearth steel slag of the steel plant are used as raw materials. As two wastes, they were mixed and pyrolyzed to prepare a composite absorbent. Further, the adsorption mechanism of the adsorbent to chromium ions in the sewage is explored. The pyrolysis reaction behavior of sludge mixed with steel slag was studied by the thermogravimetric analysis technology. SEM, BET, and XPS were used to analyze the specific surface area, pore size distribution, and pore structure characteristics of pyrolysis products, respectively. Moreover, a comprehensive analysis of the adsorbent was carried out for the adsorption mechanism of hexavalent chromium ions. The results show that the addition of steel slag promotes the pyrolysis of the sludge in each stage. When the content of steel slag is 80%, the increases of reaction rate are the most obvious with the largest increase of weight loss rate in each stage. The SEM results show that the enrichment of sludge on metal oxides is enhanced in the high-temperature range (600–700°C). Besides, when the content of steel slag is 40–60%, the mixture’s growth rate of the specific surface area can reach 600% and the growth rate of total pore volume can reach 350% (the situations of sludge as the baseline). Regarding the measurement of Cr(VI), the adsorption rate of the steel-slag solution is 50.93% and that of the sludge solution is 69%. However, the adsorption rate can be increased to 95% when the steel slag and sludge were mixed as an adsorption solution. In conclusion, the adsorption mechanism of Cr(VI) by additives is controlled by both physical and chemical processes. The present study provides a theoretical basis and technical support for the scientific and reasonable utilization of sludge and steel slag.

Production of Silicate Materials with Addition of Fine-Ground Open-Hearth Furnace Slag The necessity of expanding the local raw material base for the production of silicate building materials due to anthropogenic alumino

Production of Silicate Materials with Addition of Fine-Ground Open-Hearth Furnace Slag The necessity of expanding the local raw material base for the production of silicate building materials due to anthropogenic alumino

Reclamation of Industrial Tailings by Means of Metallurgical Slag

In a microplot field trial, the use of crushed slag to break down the capillary borders in recultivation of toxic tailings (at enrichment facilities and solid waste dumps) with minimum application of fertile soil was studied. In this approach, metallurgical wastes may be used in low-cost energy-saving technologies. Four basic types of slag produced at AO EVRAZ ZSMK in steel smelting were studied: white nonferrous slag; blast-furnace (open-hearth) slag; electrosmelting slag; and converter slag. Such slag forms an inert layer under a minimal layer of fertile soil on trial plots, where perennials (a legume–grass mixture) were planted. For each slag, we used a control plot (without fertilizer); a plot with a potassium-humate preparation; a plot with complete mineral fertilizer; and a plot with a mixture of these approaches. At the end of the growing season, the above-ground phytomass is 17–128 g/m2. The best results were obtained with converter slag and blast-furnace slag, characterized by the lowest phytoxicity. Addition of mineral fertilizer alone or in combination with potassium humate increases the phytomass by a factor of 2–4. Added alone, potassium humate had no influence on plant production but, in combination with mineral fertilizer, it increased the phytomass by a factor of 1.6–1.8. To stimulate germination and phytomass production, the addition of both mineral fertilizers and humic preparations is recommended. The converter and blast-furnace slag may be used as an inert material in reclamation, with minimum application of fertile soil. White slag and electrosmelting slag are not recommended, on account of their high phytotoxicity; in those trials, the perennials employed did not thrive.

Use of metallurgical slags in mortar production

The possibility of using the metallurgical slags of metallurgical enterprises of the Novokuznetsk city as a filler in the manufacture of mortars is shown in this work. The methodology of the research is based on the previously developed technological schemes for recycling metallurgical slags in the form of a system of work stages, which is associated with the need for a consistent transformation of the properties of slags, and what is achieved through a series of mechanical and physicochemical effects. The use of the express method of selecting the composition of aggregate fractions from open-hearth slag made it possible to obtain the densest packing of filler grains in compliance with the strength requirements for mortars. On a set of basic physical and mechanical quality indicators, experimental mortars meet the current regulatory requirements, which allows us to recommend their compositions for testing in industrial conditions.

Determination of the Basic Parameters of the Recovery Process for Extracting Iron from Iron and Steel Slag

The paper identifies the effect of temperature recovery on the iron slag output in the steel industry, the value of which is recommended to take in the range of 1600 – 1650 °C. Laboratory studies were carried out in an oven Tamman resistance. Studies have shown that an increase in the time delay interval in the molten slag 1300 – 1650 °C higher than the degree of metal removal. With the use of statistical processing dependences for determination of content of FeO content in the converter and open-hearth slag were received.

Improvement of the Compositions and Properties of Gray Ceramic Pigments

A comparative analysis of the optical and color characteristics of well-known gray ceramic pigments is performed and the effectiveness of different opacifying components in them is evaluated. Gray pigments with stable optical indicators are synthesized using open hearth slag. It is shown that zirconium compounds, characterized by inertness with respect to the coloring components in the pigment and by high resistance to dissolution by glass melts, are shown to be effective opacifiers for obtaining these pigments.

Brown ceramic pigments based on open-hearth slag

The possibility and expediency of the application of dump waste open-hearth slag for obtaining ceramic pigments was revealed on the basis of complex physicochemical studies. Ceramic pigments of a brown color gamma were synthesized in the system open-hearth slag-Cr2O3-NiO. The composition of the crystal phase of roasting products of pigment burdens and its correlation with optical color indexes were determined. Laboratory and production tests of developed slag-containing pigments in the composition of various vitreous coatings were carried out.

Black ceramic pigments based on open-hearth slag

Black ceramic pigments based on open-hearth slag are obtained. The possibility and sequence of physicalchemical processes occurring during kilning of pigment mixes are evaluated and the nature of the color-carrying phases in the products of their heat-treatment is determined. The relation between the crystal-phase composition and the optical indicators of the slag-containing pigments is studied. It is shown that such pigments are promising for coloring various glazes.

Improving slag processing at OAO MMK

Since 1993, open-hearth tailings slag and fresh converter slag has been processed in the ROXON system. Material covering a broad size class is sent to the ROXON magnetic separators. The ROXON system does not match the performance of the AMCOM equipment, in which the material is sorted into narrow size classes prior to separation. In processing converter slag at the AMCOM equipment, the iron content in the 0–10 mm magnetic product is 8.8% greater than for the ROXON system, while the total yield of magnetic products in the 0–10 and 10–50 mm classes is 1.6% greater. Laboratory data for the separation of the 0–50 mm magnetic products after stage I of ROXON separation show the efficiency of preliminary division into 0–10 and 10–50 mm classes. Thus, the ROXON system must be reconstructed with preliminary division of the material into narrow size classes. The expected economic benefit is 90 million rub.

Use of processed open-hearth dump slag for production of cast iron

Use of processed open-hearth dump slag for production of cast iron

Use of Concentrate Prepared from Discarded Open-Hearth Slag to Make Alloyed Iron for Ingot Molds

Use of Concentrate Prepared from Discarded Open-Hearth Slag to Make Alloyed Iron for Ingot Molds

Efficiency of using open-hearth slags in the treatment of steel with composite material

Efficiency of using open-hearth slags in the treatment of steel with composite material

Use of metallurgical slags in the technology of dolomite refractories

The elemental and mineral compositions of slags of blast-furnace, open-hearth, and electrosmelting production at some enterprises are analyzed. Laboratory development of a technology of stabilized dolomite refractories using 40 – 45% metallurgical slags is carried out. A high-quality product is attained by using open-hearth slags and slags from electrosmelting of alloyed steels. The quality parameters of the stabilized dolomite articles make them an alternative to chromite-periclase articles.

Open-hearth slag in glass production

The development of ecologically clean, waste-free technologies in the metallurgical industry has been a priority in recent years. In the work reported here we explored the possibility of using open-hearth slag, waste from the Northern Metallurgical Works, in glass production. The composition of the slag was as follows (%; here and below, molar content): 30 SiO2, 4 A1203, 15 CaO, 8 MgO, 12 MnO, 22 FeO, 0.ii S, 4 Cr20~, 2 P2Os, 2.89 all others.

Open Hearth Slag—A Problem Waiting to Happen

Blast furnace slag and other waste materials from steel‐making processes have long been useful in the construction industry, and perhaps for other applications. However, the stable and useful qualities of blast furnace slag do not extend to open hearth slags. In fact, there are a number of specific projects in which open hearth slag has been used as backfill beneath slabs and structures, or beneath pavements, with rather disastrous results. Forewarned is forearmed.

Use of by-products in foundation engineering : Lychko, Y M; Pevzner, M E; Belenky, N G; Ilyina, N G; Zagovora, G A Proc 10th International Conference on Soil Mechanics and Foundation Engineering, Stockholm, 15–19 June 1981V3, P733–734. Publ Rotterdam: A. A. Balkema, 1981

The paper deals with methods of stabilization and improvement of steel-smelting waste products, that is, open-hearth slag, and of wastes obtained from sulphur ore treatment processes, that is, water-saturated carbonate sludge. Some examples of utilization of fresh and dump slags in foundation practice are presented. A method is given for desiccation of carbonate sludges by treatment with a non-uniform direct electric field which greatly improves their physicomechanical characteristics. (TRRL)

Physicochemical properties of open-hearth slags with a high limestone content in the cold charge

Physicochemical properties of open-hearth slags with a high limestone content in the cold charge

Synthesis of sitalls from open-hearth slag

Synthesis of sitalls from open-hearth slag