This article is devoted to basalt reprocessing together with magnetite concentrate in order to obtain ferrous alloy and calcium carbide. The studies have been based on thermodynamic simulation and electric smelting in arc furnace. The thermodynamic simulation has been performed using HSC-5.1 software based on the principle of minimum Gibbs energy. The blend was smelted in arc furnaces. On the basis of the obtained results of combined processing of basalt, it has been established that under equilibrium conditions, the increase in carbon content from 36 to 42 wt % of basalt and concentrate mixture makes it possible to increase the aluminum extraction into the alloy up to 81.4%, calcium into calcium carbide – up to 51.4%, and silicon into the alloy – up to 78.5%. Increase in the amount of lime to 32% allows to increase the content of calcium carbide to 278 dm3/kg. Electric smelting of the blend under laboratory conditions in the presence of 17-32% of lime makes it possible to extract ferrous alloy containing 69.5-72.8% of silicon, 69.1-70.2% of aluminum, and to obtain ferrous alloy containing 49-53% of ΣSi and Al and calcium carbide in the amount of 233-278 dm3/kg. During large-scale laboratory smelting of blend comprised of basalt (38.5%), magnetite concentrate (13.4%), lime (15.4%), and coke fines (32.7%), the ferrous alloy has been produced containing 48-53% of ΣSi and Al, calcium carbide in amount of 240-260 dm3/kg. Extraction of Si and Al into the alloy was 70.4 and 68.6%, respectively; Ca into carbide – 60.3%; Zn and Pb into sublimates – 99.6 and 92.8%, respectively.
The paper presents data concerning the total production of castings over the 2000-2014 period, both on a global scale, and in Poland. The
basic types of casting alloys were taken into account. Changes in the production volume and structure over the period of the analysed 15
years were pointed out with respect to countries leading in foundry production. The topmost position in the world foundry industry is held
by China for several years (with almost 45% share in the foundry market), the second place is taken by India (with almost 9% share). A
distinct reduction in the shares of the once significant producers of castings, such as USA, Japan, Germany, Russia, Italy, or France, was
observed over the 2000-2014 period. Poland had a share of 1.16% in 2000, and of 1.02% in 2014. Comparing the detailed data concerning
the years 2000 and 2014, one can see that the fractions of castings made of ductile iron, cast steel, aluminium alloys, or magnesium alloys
increase on a global scale, while such alloys as grey cast iron or malleable are in decline.
The paper presents the issue of synthetic cast iron production in the electric induction furnace exclusively on the steel scrap base. Silicon
carbide and synthetic graphite were used as carburizers. The carburizers were introduced with solid charge or added on the liquid metal
surface. The chemical analysis of the produced cast iron, the carburization efficiency and microstructure features were presented in the
paper. It was stated that ferrosilicon can be replaced by silicon carbide during the synthetic cast iron melting process. However, due to its
chemical composition (30% C and 70% Si) which causes significant silicon content in iron increase, the carbon deficit can be partly
compensated by the carburizer introduction. Moreover it was shown that the best carbon and silicon assimilation rate is obtained where the
silicon carbide is being introduced together with solid charge. When it is thrown onto liquid alloy surface the efficiency of the process is
almost two times less and the melting process lasts dozen minutes long. The microstructure of the cast iron produced with the silicon
carbide shows more bulky graphite flakes than inside the microstructure of cast iron produced on the pig iron base.
The paper presents an original method of measuring the actual chromite content in the circulating moulding sand of foundry. This type of
material is applied for production of moulds. This is the case of foundry which most frequently perform heavy casting in which for the
construction of chemical hardening mould is used, both the quartz sand and chromite sand. After the dry reclamation of used moulding
sand, both types of sands are mixed in various ratios resulting that in reclaimed sand silos, the layers of varying content of chromite in
mixture are observed. For chromite recuperation from the circulating moulding sand there are applied the appropriate installations
equipped with separate elements generating locally strong magnetic field. The knowledge of the current ratio of chromite and quartz sand
allows to optimize the settings of installation and control of the separation efficiency. The arduous and time-consuming method of
determining the content of chromite using bromoform liquid requires operational powers and precautions during using this toxic liquid.
It was developed and tested the new, uncomplicated gravimetric laboratory method using powerful permanent magnets (neodymium).
The method is used in the production conditions of casting for current inspection of chromite quantity in used sand in reclamation plant.
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