Pyrometallurgical Slags in Upper and Lower Silesia (Poland): from Environmental Risks to Use of Slag-based Products – a Review (original) (raw)
Related papers
Applied Geochemistry, 2014
Editorial handling by M. Kersten a b s t r a c t Slags from base metal smelting are often deposited for over 100 years with no barriers between the heap and the surrounding environment. Observations at the external surfaces of the slag heaps may not reflect the state of the slag material inside the slag heap. A slag heap from Zn-Pb ore smelting (Ś wię tochłowice, Upper Silesia, Poland) was disturbed during recent slag removal and the freshly uncovered surfaces are examined in this study. The material forming the interior of the slag heap is fine-grained (up to 5 cm) and strongly weathered (called the weathered slag zone) in contrast to the large slag boulders on the surface of the slag heap (up to 2 m), which are only slightly weathered. The weathered slag zone is composed of gypsum and hematite plus a mixture of primary and other secondary phases. The weathered material as a whole is chemically more homogenous than unweathered slags and has lower Si and higher Fe, Pb (up to 3 wt.%) and Cd (up to 560 mg/kg) concentrations. SEM images show that primary slag phases are porous and disintegrated. The examined surfaces are 3-4 m high and 10-30 m wide suggesting that such slag weathering may have occurred in more extensive parts of the slag heap. Weathering affects slag types with different phase compositions and is therefore controlled by specific conditions occurring within the heap, not by the type of slag. These conditions are so far not well defined, but may include prolonged slag deposition, slow water transfer within the heap and interaction of slags with acid rains common in the Upper Silesia region.
Archives of Foundry Engineering
There are two methods to produce primary copper: hydrometallurgical and pyrometallurgical. Copper concentrates, from which copper matte is melted, constitute the charge at melting primary copper in the pyrometallurgical process. This process consists of a few stages, of which the basic ones are roasting and smelting. Smelting process may be bath and flash. Slag from copper production, on the end of process contain less 0,8%. It is treat as a waste or used other field, but only in a few friction. The slag amount for waste management or storage equaled 11 741 – 16 011 million tons in 2011. This is a serious ecological problem. The following slags were investigated: slag originated from the primary copper production process in the flash furnace of the Outtokumpuja Company in HM Głogów 2 (Sample S2): the same slag after the copper removal performed according the up to now technology (Sample S1): slag originated from the primary copper production process in the flash furnace of the Outto...
Polityka Energetyczna – Energy Policy Journal, 2021
The relevance of the study is due to the need to identify the problems, features and consequences of strategic transformations in the metallurgical industry of Ukraine in the context of reviewing the circular process of organization of the economy, where the blast furnace, open-hearth and rolling production waste are of a high potential. The reuse of metallurgical waste has a number of economic advantages in terms of the chemical composition of the product life cycle. Blast furnace slag is suitable as a raw material in cement production and can be used as fillers in the construction of roads, hydraulic and environmental facilities, during reclamation works, etc. Agriculture actively uses slag as a fertilizer that contains potassium, magnesium, phosphorus, magnesium, boron-as an additive that reduces soil acidity. Currently, all slag can be processed into fertilizers or building materials. The economic effect of the use of slag in construction is accounted for in the relatively low cost of products, improvement of the quality and durability of the structures. The main positive consequences of smartization of the metallurgical industry are increase of its resource efficiency and environmental friendliness, negative-the low level of blast furnace slag use in various sectors of the economy compared to the experience of developed countries, an insufficiently developed legal framework. The mechanism of state management of the use of secondary raw materials, especially metallurgical origin, in conditions of shortage of energy resources and the intensive use of non-renewable natural resources remains an important scientific problem and requires further research.
Steel Slag and Waste Management
Key Engineering Materials, 2004
Steel slag is a waste material produced during the process of steel making. For many years, a large amount of steel slag was deposited in slag storing yards, occupied farmland, silted rivers and polluted the environment. Many steel plants in the world have already taken up innovative waste recycling technologies with the ultimate objective of 100% recycling. There is much to be improved in using steel slags in Turkey. The comprehensive utilization of steel slag is important for environmental protection and resource reuse in Turkey and abroad. It is clear that steel slag must meet appropriate performance specifications before being adopted for a particular application. The aim of the present research was to characterize steel slag from a Turkish company and compare to the steel slags from various countries. Application possibilities have been sought by comparing properties to the other steel slags.
Utilization of Slags from Foundry Process
Journal of Casting & Materials Engineering
The melting of steel or cast iron is one step of the foundry process. The foundry industry uses different types of furnaces, and metallurgical slags are products of the pyrometallurgical processes defecting in these furnaces. Furnace slag is a non-metallic by-product that consists primarily of silicates, alumina silicates, and calcium-alumina-silicates. As a by-product of the melting process, furnace slags vary considerably in form depending on the melted metal furnace types, and slag cooling method used. Most quantity of slags from the foundry processes are created in a cupola furnace that is used for cast iron production. An electric arc furnace is usually used for steel production, but it can be used for cast iron production as well. Universal use features an electric induction furnace. Slags from the melting processes in a foundry can be in the form of gravel, or the slag from a cupola furnace can be granulated. The utilization of slags from foundry processes is very delimited in Slovakia because of their quantity. This article deals with the possibility of using foundry slag as a binder in civil engineering. A basic property of a binder in civil engineering is its hydraulicity, which can be given by compression strength. Four metallurgical slags were tested. The values of the compressive strength of the slags were low, but addition cement to the slags resulted in a strong increase in the value of the compressive strength.
Treatments and Recycling of Metallurgical Slags
Recovery and Utilization of Metallurgical Solid Waste [Working Title], 2018
Steelmaking plants continuously strive to reduce the environmental load in the steelmaking process, resulting in the recycling of energy, water, and other byproducts. In this chapter, techniques for the treatment and recycling of metallurgical slags are described. Metallurgical slags are considered secondary raw materials and are used or added during the process to improve steelmaking practice. Steelmaking slag added into ladle slags makes it possible to minimize slag line wear. BOF-converter slags are also applied in buildup, foaming, or slag splashing practices carried out to prolong the lifespan of refractory lining. Also, EAF slags are commonly used to avoid refractory wear and decrease energy consumption. It is known that cement concrete is one of the most common building materials. Blast furnace crystallized slags are used in cement production, in different percentages. In this sense, understanding the properties of slags is a prerequisite to apply them in different functions. This chapter deals with the measurement and modeling of thermochemical properties of slags, thermophysical properties, and interproperty correlations. Different experimental tests applied in slag characterization are also detailed.
Research Square (Research Square), 2022
The studies of the impact of post-metallurgical land ll were conducted in Siechnice near Wrocław, Lower Silesia. The samples of sediments and water were taken at different distances from the slag heap area. We assessed the metal concentrations in the samples, then ecotoxicological tests were conducted as well. Ostracodtoxkit F was performed to measure the toxicity of sediments. Daphtoxkit F magna and Algaltoxkit F tests were performed to evaluate water quality. 30% mortality rate of H. incongruens (Ostracodtoxkit F) was recorded in sediment studies in the closest site to the waste dump. The highest mortality rate of D.magna in 100% dilution after 48 hours was observed in water samples taken from the closest distance to slag heap, and the death rate did not exceed 50%, therefore it was not possible to establish LC50. The concentrations of selected heavy metals (Zn, Cu, Pb, Fe, Cr) were determined in sediment samples. It was found that the closest site to the land ll was moderately/heavily polluted with Cr according to LAWA classi cation. The health risk assessment of the sediments was estimated by calculating non-carcinogenic health risk such as Hazard Quotient (HQ), Hazard Index (HI); and carcinogenic risk-Excessive Risk of Cancer Development (ECR). Hazard Index (HI ing) for Cr was exceeding 1 for children, implying possible adverse health effects might occur. ECR values for Cr and Pb were above the range limit of 10 in all sample points. But the cancer risk was found to be very low. Article Highlights The closest site to the waste dump is moderately/heavily polluted with Cr (class II-III) and moderately polluted with Cu (class II). Highest mortality rate was also recorded in the nearest site to the slag heap. Non-cancer and cancer risks are higher as well in nearest water body to the land ll than other 2 sites.
Due to growing environmental awareness, as well as stricter regulations on managing industrial waste, the world is increasingly turning to researching properties of industrial waste and finding solutions on using its valuable component parts so that those might be used as secondary raw material in other industrial branches. Although metallurgical slag is still today considered waste and is categorized in industrial waste catalogues in most countries in the world, it is most definitely not waste, neither by its physical and chemical properties not according to data on its use as valuable material for different purposes. Moreover, since the earliest times of the discovery and development of processes of iron and other metals production, slag as by-product is used for satisfying diverse human needs, from the production of medicines and agro-technical agents to production of cement and construction elements. This paper demonstrates the possibilities of using slag as one small part of industrial waste arising from the metallurgical processes of iron and steel production. Considering the specificity of physical and chemical properties of metallurgical slags and a series of possibilities for their use in other industrial branches, this paper pays special attention to slag significant trough the history and its using in the road construction.
The Canadian Mineralogist
Slags produced by the pyrometallurgical treatment of Zn ore, deposited at the dump in Świętochłowice, in Upper Silesia, southern Poland, are dominated by synthetic analogues of olivine, melilite, pyroxene, feldspars, willemite, zincite and spinel, occurring in various assemblages. Secondary phases either formed at high-temperature or due to weathering are both common at the pile. They include efflorescences of gypsum, epsomite, hexahydrite and bianchite, encrustations of gypsum, anglesite and cerussite, and accumulations of jarosite, goethite and hematite. Two groups are identified: the first one, where sulfates are dominant, is ubiquitous; the second one, of local importance, has originated under conditions varying significantly from one place to another. The weathered phases originate during episodic outflow of water from the pile after rainfall. These mineralogical data and leaching experiments show that, among the primary phases, zincite is most readily weathered, followed by willemite, melilite and the spinel-group phases.