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The foundry industry is a major producer of industrial waste, with used foundry sands (UFS) representing the largest share. While bentonite-bonded sands can be reused multiple times, sands with organic binders are typically single-use and are often landfilled due to limited regeneration capacity. Their valorization in construction materials represents an important pathway toward circular economy. This study evaluates the use of UFS from three different foundries, including bentonite- and furan-bonded systems, as p...

Particulate pollutants are generated at all stages of the preparation of the moulding and core mixture, during the handling of raw materials, during mixing and preparation of the moulding mixture in the mixers, during the moulding process itself, and during both manual and machine moulding. The reason for the generation of a relatively large amount of dust in all the operations associated with the manufacture of moulds and cores is the moulding mixture used, the basis of which is abrasive, i.e. sand, whether quart...

Cupola furnaces are still considered the most suitable furnace units for cast iron melting. Typical exhaust gas from a cupola furnace contains CO, SO2 and NOx. A relatively large amount of dust emissions are emitted from the cupola furnace. These are formed during melting in the cupola furnace. These emitted particles can contain CaO, FeO, Pb, MnO, MgO, SiO2 and Zn. Crushing and mechanical abrasion during charge preparation and charging generate particles, some of which are emitted immediately. Dust is also genera...

Gray cast iron is still the most used material for the production of castings. It can be made in several ways, but the most efficient and economical way to make gray cast iron is in a cupola furnace. A by-product in its production is slag, which arises from impurities that may be present in the charge, from coke, which is used as fuel for the cupola furnace and part of it also passes into the slag, from the lining of the cupola furnace as well as from oxides formed during of the smelting process, sulfides and phos...

Briquetting is the pressing of dusty materials into pieces of the same shape and size. Briquetting can be done without a binder or with the addition of a binder to the briquetting mixture. Briquettes can have any shape, but the most common is the shape of a cylinder. The briquettes must be strong enough to eliminate the possibility of damage during transport and must be strong enough even at high temperatures. The briquettes have a regular shape, have the same weight, are more durable and easier to transport. They...

In the production process of cast iron and steel castings, a large amount of waste is generated. Each stage of production of castings generates a certain type or types of waste. The largest volume of waste is the used molding compound, followed by slags from melting processes and dust, the creation of which is copied by the entire foundry process. Dust waste is generated from the beginning to the end of the production cycle in the foundry. Finishing operations represent, in addition to a large source of noise, a l...

Concrete is a building material composed of aggregate, cement and water. Aggregate forms a filler, cement, after mixing with water, creates crystals that connect the aggregate with a firm and flexible bond. Cement slurry gradually loses its plasticity and begins to solidify and harden, until it finally turns into cement stone. Quartz sand is most often used as aggregate. Concrete is a building material composed of aggregate, cement and water. Aggregate forms a filler, cement, when mixed with water, forms crystals ...

The paper deals with the ? + ? titanium alloys, due to their good properties such as low specific weight and high values of mechanical properties have found wide application as a construction material. Their disadvantage is high price and complicated production of the basic material - titanium but also alloying components (molybdenum, chromium), associated with high energy demand and undesirable effects on ecology. The inhomogeneity of the deformation with formation of deformation bands are typical for these alloy...

In the context of the recycling of waste from wrought aluminum alloys, especially food packaging, these were re-melted and cast into bars. The alloy thus obtained contains up to 2.0% Si, 0.8% Cu, 2.0% Fe, 2.5% Mn and other elements in tenths of %. The problem in its further processing is the porosity. Several methods were used to quantify it, of which the most accurate method was weighing. The disadvantage of this method is the requirements of the competence of the personnel as well as technical equipment. Other m...

Production of castings plays an important part in the global and in the national economy. The main recipient of the foundry production is the automotive industry, but castings find application also in other branches of industry, in civil engineering, in farming, in medicine, and can as well serve art production. In 2016, worldwide casting production reached 104.1 million metric tons, a shade over the 103.7 million metric tons produced in 2015. The remaining 2015 top 10 casting nations by tonnage are Japan at 5.4 m...

The property that influences the binding properties of slag is its hydraulicity. The term ?hydraulicity? is now used internationally to describe cements and other binders that set and harden as a result of chemical reactions with water and continue to harden even if subsequently placed under water. There are a few exceptions but these chemical reactions generally involve calcium, silica, and aluminum constituents that react with water to form a whole family of calcium silicate and calcium aluminate hydrates. The c...

The manufacturing and processing of metals is connecting with large number of different types of wastes. One kind of these wastes are dusts and sludges which arise as a result of the melting processes or in the machining of castings. Flue dusts from melting processes are captured most often on filters, scrubbers or in Venturi scrubbers. Dust particles resulting from the machining of castings (grinding and blast cleaning) remain in the grinding rooms or they are sucked and collected on filters. Whereas these dusts ...

Various metallurgical slags are generated in metal extraction, refining and alloying processes. Due to the large slag quantities and the strict erenvironmental regulations, recycling and utilization of these slags are an attractive alternative in order to reduce and eventually to eliminate the disposal cost, to minimize the related environmental pollution, and to save the resource conservation.The global warming effect and natural resource saving are the general environmental topics nowadays. In addition, the land...

Recycling is the method used to reduce the environmental impact of large volumes of materials, the sparing use of resources is another relevant factor here. The waste materials which occur in the foundry and st eel industry alongside the target products most be used elsewhere or returned to the foundry and steelmaking processes. The result will be that the need to dispose of material s will be greatly reduced , so alleviating the demand for landfill capacity. In addition, raw material depo sits will be conserved a...

The foundry industry, itself, is one of the wo rldВґs first recyclers. Foundries have been making new metal objects by remelting old ones. An estimated 15 to 20 million tons of scrap metal that would otherwise be sent to overcrowded landfills are being remade into new castings each year. As with most industries, the foundry industry generates its own by-products. Typical by-product streams from the foundry indus try include foundry sand, foundry slag, baghouse dust, and furnace and ladle refractory. In order to co...

Slag from pig iron, steel and cast iron production belong to metallurgical slag. A blast furnace slag is from pig iron production, slag from electric arc furnace and electric induction furnace are from steel production and stag from cupola furnace proceeds from cast iron production. There are given basic information about chemical composition and physical properties of slag in this contribution (melting temperature). As another properties basicity, content of free lime and structure of slag will be determined. Che...

Fly dusts creates by steel and cast iron melting. Their properties depends on a type of melting aggregate. For steel it is first of all a fly dust from electric arc furnace, its chemical composition is depended on the kind of produced steel. A cupola furnace is the most used furnace for cast iron production. Fly dusts from steel and cast iron production contain some part of FeO that is reducible in a cupola and blast furnace. It is a very fine material and it has to be pelletized or briquetted before its next use....

Foundries produce metal castings from ferrous or non-ferrous alloys and they operate in various locations around the world. A typical foundry workplace is composed of furnace area, pouring area, core making area, shaking out area and fettling area. The manufacturing process involves the melting of metal into a liquid, the pouring of molten metal into a cast, the removing of casting and the cleaning / finishing of the cast piece. Dusts arise almost in every of these steps of foundry processes. Solid waste streams f...

Returnable and non-returnable losses rise during melting and casting of molten metal. Non – returnable losses arise by melting and metallurgical treatment of molten metal as a back wash of evaporation, chemical reactions between molten metal and refractory lining, molten metal and air and between molten metal and refining additions. Value of these losses depends on the kind of alloy, on used furnace and charge quality. Except non-returnable losses, the returnable losses creates by melting. They represent a diffe...

Slag are by-products by metallurgical processes. The most famous slag are blast furnace slag and steel slag. Their treatment and using are known and their using is very extensive. Cupola slag formats by cast- iron production in cupola furnace. In some countries it is used by roadway building but in Slovakia it is waste only. In some European countries it is granulated and granulation product is used in building industry. Cupola slag is after tipping from cupola furnace casted in to slag dip and put in to waste dep...

Dusts arise in every step of foundry process. A lot of dust create by mould sands and core sands preparation. Their composition depend on used binder. The main compound of these dusts is SiO2 and by mould sands with organic binder it is carbon too. A melting process is connected with formation of flue dust, its composition depends on charge composition. Cupola furnaces, electric arc furnaces and induction furnaces are used in foundry. The most quantity of dust is produced from cupola furnace. It is very fine-grain...

Return material consists of gating, risers and residues from cold chamber, defective castings and another residues from die casting. This material has to be degreased from the fatty and separating agents that are usually of oil origin. In common praxis the clean and contaminated material is put in to melting furnace, it is melted and new alloys are added in the form of small pieces. Within the frame of experiments the influence of contaminated return material in the charge on quality die castings was observed. The...

The European foundry industry is the third largest in the world for ferrous castings and the second largest for non-ferrous ones. the annual production of castings in the enlarged European Union amounts 11.7 million tonnes of ferrous and 2.8 million tonnes of non-ferrous castings. The foundry industry is a major player in the recycling of metals. steel, cast iron and aluminium scrap is remelted into new products. The most possible negative environmental effects of foundries are related to the presence of a thermal...