The problem of harmful casting resins has been present in foundries for many years. Manufacturers are introducing new products that contain in their composition environmentally and eco-friendly ingredients. Unfortunately, not all types of technology can be used, sometimes environmental benefits are disproportionate to the quality of castings and their price. In the foundry industry, the most popular binders are based on organic compounds (often carcinogenic) and other harmful substances. Due to strict legal regulations regarding environmental protection, as well as care for the foundry's workers' comfort - their occurrence should be reduce to a minimum. These compounds often behave also depending on the conditions of use (temperature, atmosphere). The application of various methods of thermal analysis and spectroscopic methods allows to verify the mechanism of resin decomposition process in relation to conditions in the form in both inert and oxidizing atmosphere. For analysis the resins from cold-box technology, were used TG–DTG–DSC, Py-GC/MS methods and specified the course of changes occurring in combination of different atmosphere.
The results of investigations of the granulation process of foundry dusts generated in the dry mechanical reclamation process of used sands, where furan resins were binders are presented in the paper. Investigations concerned producing of granules of the determined dimensions and strength parameters. Granules were formed from the dusts mixture consisting in 50 mass% of dusts obtained after the reclamation of the furane sands and in 50 mass % of dusts from sands with bentonite. Dusts from the bentonite sands with water were used as a binder allowing the granulation of after reclamation dusts from the furane sands. The following parameters of the ready final product were determined: moisture content (W), shatter test of granules (Wz) performed directly after the granulation process and after 1, 3, 5, 10 days and nights of seasoning, water-resistance of granules after 24 hours of being immersed in water, surface porosity ep and volumetric porosity ev. In addition the shatter test and water-resistance of granulate dried at a temperature of 105oC were determined. Investigations were performed at the bowl angle of inclination 45o, for three rotational speeds of the bowl being: 10, 15, 20 rpm. For the speed of 10 rpm the granulation tests of dusts mixture after the preliminary mixing in the roller mixer and with the addition of water-glass in the amount of 2% in relation to the amount of dust were carried out. The obtained results indicate that the granulator allows to obtain granules from dusts originated from the reclamations of moulding sands with the furane resin with an addition of dusts from the bentonite sands processing plants.
This article presents data on the anthropogenic air emissions of selected substances (CO2, SO2, total suspended particles (TSP), dioxins
and furans (PCDD/F), Pb and Cd) subject to reporting under the Climate Convention (UNFCCC) or the Convention on Long-range
Transboundary Air Pollution (UNECE CLRTAP). It also presents the national emissions of these substances in 2014 by the major source
categories and defines the share of metal production in these emissions. Analysis is based on national emission inventory reports. Most
important source of air emission in case of CO2 and SO2 is 1.A.1 Energy industries category. TSP and PCDD/F are emitted mainly from
fuel combustion in small sources (i.a. households). Emission of heavy metals (Pb and Cd) is connected mostly with 1.A.2. Manufacturing
industries and construction category. Metallurgy is significant source of emission only for lead and cadmium from among all considered
substances. The shares of particular sectors in the national emissions of given pollutants are important, in view of the possible reduction
measures and the determination in which industries they could bring about tangible results.
No-bake process refers to the use of chemical binders to bond the moulding sand. Sand is moved to the mould fill station in preparation for
filling of the mould. A mixer is used to blend the sand with the chemical binder and activator. As the sand exits the mixer, the binder
begins the chemical process of hardening. This paper presents the results of decomposition of the moulding sands with modified ureafurfuryl
resin (with the low content of furfuryl alcohol below 25 % and different activators: organic and inorganic) on a quartz matrix,
under semi-industrial conditions. Investigations of the gases emission in the test foundry plant were executed according to the method
extended in the Faculty of Foundry Engineering (AGH University of Science and Technology). Article presents the results of the emitted
chosen aromatic hydrocarbons and loss on ignition compared with the different activators used to harden this resin. On the bases of the
data, it is possible to determine the content of the emitted dangerous substances from the moulding sand according to the content of loss on
ignition.
In the projects of protection of soil-water environment there is a need to combine and process large amount of information from various disciplines to estimate parameters of phenomena and to determine the range and time table of necessary undertakings.
Due to complex assessment of processes taking place in aquifers, mathematical modeling is the best tool supporting evaluation off pollution in the ground water environment. It is also an effective method of forecasting the risk associated with the harmful impact of objects polluting grounds and grounds waters.
Significant application of mathematical modeling is the use for the enlargement of information gathered in the process of recognition and assessment of condition that prevail in soil-water environment. Results of modeling, if appropriately presented, could be an important element of decision support system in environmental management.
This paper describes procedures for developing an environmental remediation decision support system by linking CADD and GIS software with the hydro geological flow and transport models.
In the present work, different Cu-alloyed model ductile irons with ferritic (0%Cu-0.09%Mn), mixed ferritic-pearlitic (0.38%Cu-0.40%Mn) and pearlitic (0.69%Cu-0.63%Mn) microstructure were produced and analyzed in terms of their electrochemical corrosion behavior in a 3.5wt.%NaCl aqueous solution containing naturally dissolved oxygen at room temperature (25°C). The remaining elements such as Si and Mg were kept at balanced levels in an attempt to minimize variations in graphite size and distribution among different samples. The corrosion resistance was evaluated by electrochemical impedance spectroscopy and potentiodynamic polarization. Microstructure analysis of the cast alloys confirmed similarity in the graphite morphology among the different cast samples and the expected variations in the metallic matrix. In the absence of passivation, it was found that the addition of copper led to an increase in corrosion resistance, which could be attested by higher values polarization resistance and corrosion potential.
The analysis of after reclamation dusts generated during the reclamation treatment of test portions of two kinds of polydispersive material in the Regmas device, is presented in the hereby paper. For the comparative purpose the fresh moulding sand marked as quartz sand „Sibelco” –1K 0.40/0.32/0.20, J88, >14000C, WK = 1.20 (acc. PN-83/H-11077), as well as the spent moulding sand, which was previously subjected to the primary reclamation and to dedusting, were used. Conditions of the process treatment were forced by the frequency of supplying the vibratory drive motors being successively 40, 50 and 60Hz for 5, 10 and 15 min. and by causing a diversified material flow through the functional system of the device (charging hopper, abrasive chamber acting as a buffer space). Two states of the process treatment, when a material was flowing through the chamber, were applied. In the first one, an intergranular surface abrasion of grains occurred as a result of the granular material circulation in the chamber forced by the vibratory drive. In the second one, the forced material flow was performed in the presence of crushing elements (steel balls), additionally introduced into the abrasive chamber. Analyses of the device influence were performed by determinations of the amount of dusts separated in the pneumatic classifier and analysis of their grain sizes by means of Analysette 22NanoTec.
The research focuses on assessing the metal content, mainly copper, lead, iron and also silver in metallurgical slag samples from the area
where historical metallurgical industry functioned. In the smelter located in Mogiła, near Krakow (southern Poland), whose operation is
confirmed in sources from 1469, copper was probably refined as well as silver was separated from copper. Based on the change of
chemical and soil phase content and also taking cartographic and historical data into account, considering the restrictions resulting from
the modern land use the area was determined whose geochemical mapping can point to the location of the 15th century Jan Thurzo’s
smelter in Mogiła near Krakow. Moreover, using the same approach with the samples of this kind here as with hazardous waste, an
attempt has been made to assess their impact on the environment. Thereby, taking the geoenvironmental conditions into account, potential
impact of the industrial activity has been assessed, which probably left large scale changes in the substratum, manifested in the structure,
chemical content and soil phase changes. Discovering areas which are contaminated above the standard value can help to identify
historical human activities, and finding the context in artefacts allows to treat geochemical anomalies as a geochronological marker. For
this purpose the best are bed sediments, at present buried in the ground, of historical ditches draining the area of the supposed smelter.
Correlating their qualities with analogical research of archeologically identified slags and other waste material allows for reconstructing
the anthropopressure stages and the evaluation of their effects. The operation of Jan Thurzo’s smelter is significant for the history of
mining and metallurgy of Poland and Central and Eastern Europe.
Growing emission requirements are forcing the foundry industry to seek new, more environmentally friendly solutions. One of the
solutions may be the technologies of preparing moulding and core sands using organic biodegradable materials
as binders. However, not only environmental requirements grow but also those related to the technological properties
of moulding sand. Advancing automation and mechanization of the foundry industry brings new challenges related to the moulding sands.
Low elasticity may cause defects during assembly of cores or moulds by the manipulators.
The paper presents the study of flexibility in the room temperature according to new method and resistance to thermal deformation of selfhardening
moulding sands with furfuryl resin, containing biodegradable material PCL. The task of the new additive is to reduce the
moulding sands harmfulness to the environment and increase its flexibility in the room temperature. The impact of the additive and the
effect of the amount of binder on the properties of mentioned moulding sands were analysed. Studies have shown that the use of 5% of
PCL does not change the nature of the thermal deformation curve, improves the bending strength of tested moulding mixtures and
increases their flexibility at room temperature.
Non-metallic inclusions found in steel can affect its performance characteristics. Their impact depends not only on their quality, but also,
among others, on their size and distribution in the steel volume. The literature mainly describes the results of tests on hard steels,
particularly bearing steels. The amount of non-metallic inclusions found in steel with a medium carbon content melted under industrial
conditions is rarely presented in the literature. The tested steel was melted in an electric arc furnace and then desulfurized and argonrefined.
Seven typical industrial melts were analyzed, in which ca. 75% secondary raw materials were used. The amount of non-metallic
inclusions was determined by optical and extraction methods. The test results are presented using stereometric indices. Inclusions are
characterized by measuring ranges. The chemical composition of steel and contents of inclusions in every melts are presented. The results
are shown in graphical form. The presented analysis of the tests results on the amount and size of non-metallic inclusions can be used to
assess them operational strength and durability of steel melted and refined in the desulfurization and argon refining processes.
In this article, there were presented results of research on influence of reclamation process on the ecological quality of reclaim sand with furan resin used in nonferrous foundry. The quality of reclaimed sand is mainly define by two group of chemical substances from elution of reclaimed sand: Dissolves Organic Carbon (DOC) and Total Dissolves Solids (TDS). Reclaimed sand used in test was prepared in experimental thermal reclaimer and mechanical vibration reclaimer REGMAS installed in Faculty of Foundry Engineering at University of Science and Technology in Krakow. The reference point is molding sand shaking out and crumble in jaw crusher. Test of elution was made in acreditation laboratory in Center For Research and Environmental Control in Katowice up to the standard with Dissolves Organic Carbon (DOC) - PN-EN 1484:1999; Total Dissolves Solids (TDS) - PN-EN 15216:2010. The standard for elution test is PN-EN 12457- 4:2006. Except that we were made loss of ignition test, to check how many resin was rest on sand grains.
The article shows the influence of environment requirements on changes in different foundry moulding sands technologies such as cold
box, self-hardening moulding sands and green sands. The aim of the article is to show the possibility of using the biodegradable materials
as binders (or parts of binders’ compositions) for foundry moulding and core sands. The authors concentrated on the possibility of
preparing new binders consisting of typical synthetic resins - commonly used in foundry practice - and biodegradable materials. According
to own research it is presumed that using biodegradable materials as a part of new binders’ compositions may cause not only lower toxicity
and better ability to reclaim, but may also accelerate the biodegradation rate of used binders. What’s more, using some kinds of
biodegradable materials may improve flexibility of moulding sands with polymeric binder. The conducted research was introductory and
took into account bending strength and thermal properties of furan moulding sands with biodegradable material (PCL). The research
proved that new biodegradable additive did not decrease the tested properties.
In the foundry industry, many harmful compounds can be found, which as a result of gradual but long-term exposure to employees bring negative results. One of such compounds is phenol (aromatic organic compound), which its vapours are corrosive to the eyes, the skin, and the respiratory tract. Exposition to this compound also may cause harmful effects on the central nervous system and heart, resulting in dysrhythmia, seizures, and coma. Phenol is a component of many foundry resins, especially used in shell moulds in the form of resincoated sands. In order to identify it, the pyrolysis gas chromatography-mass spectrometry method (Py-GC/MS) was used. The tests were carried out in conditions close to real (shell mould process – temperature 300°C). During the measurement, attention was focused on the appropriate selection of chromatographic analysis conditions in order to best separate the compounds, as it is difficult to separate the phenol and its derivatives. The identification of compounds was based on own standards.
One of the biggest problems for sand casting foundries must be the waste produced from disposable molds. Stricter environmental regulations make it harder to dispose of waste sand, so a truly competitive foundry does no longer only make great products, but also concentrates on a sustainable casting process. While methods for repurposing waste foundry sand are still limited, the internal circulation of such sands proves significant possibilities. This paper will focus on thermal reclamation of foundry sands in a special rotating drum furnace in a central facility to serve several foundries. Thermal reclamation is a process for handling foundry sands in elevated temperatures to combust unwanted substances from reusable base sand. The introduction focuses on background of the Finnish foundry business, the most common sand systems in Finland and their reclaim properties. The experimental part features presentation of the new reclamation plant process and the conducted test runs. The samples collected from each test run have been laboratory tested to assure proper sand quality. The results of this work showed that the reclamation of alkaline phenolic no-bake sands was excellent. Reclamation of green sands did not provide satisfactory results as expected and the reclamation of furan no-bake sands provided mixed results, as the raw material was imperfect to begin with. The most important result of this work is still the successful initiation of a centralized thermal reclamation plant, with the ability to reclaim sands of several foundries. With this all of industrial symbiosis, circular economy and sustainability advanced in Finland, and the future development of this plant provides even further opportunities and a possibility to spread the ideas on a global scale.
Nowadays, the most popular production method for manufacturing high quality casts of aluminium alloys is the hot and cold chamber die casting. Die casts made of hypereutectoid silumin Silafont 36 AlSi9Mg are used for construction elements in the automotive industry. The influence of the metal input and circulating scrap proportion on porosity and mechanical properties of the cast has been examined and the results have been shown in this article. A little porosity in samples has not influenced the details strength and the addition of the circulating scrap has contributed to the growth of the maximum tensile force. Introducing 80% of the circulating scrap has caused great porosity which led to reduce the strength of the detail. The proportion of 40% of the metal input and 60% of the circulating scrap is a configuration safe for the details quality in terms of porosity and mechanical strength.
Today, about two thirds of iron alloys casting (especially for graphitizing alloys of iron) are produced into green sand systems with usually organically bonded cores. Separation of core sands from the green sand mixture is very difficult, after pouring. The core sand concentration increase due to circulation of green sand mixture in a closed circulation system. Furthermore in some foundries, core sands have been adding to green sand systems as a replacement for new sands. The goal of this contribution is: “How the green sand systems are influenced by core sands?” This effect is considered by determination of selected technological properties and degree of green sand system re-bonding. From the studies, which have been published yet, there is not consistent opinion on influence of core sand dilution on green sand system properties. In order to simulation of the effect of core sands on the technological properties of green sands, there were applied the most common used technologies of cores production, which are based on bonding with phenolic resin. Core sand concentration added to green sand system, was up to 50 %. Influence of core sand dilution on basic properties of green sand systems was determined by evaluation of basic industrial properties: moisture, green compression strength and splitting strength, wet tensile strength, mixture stability against staling and physical-chemistry properties (pH, conductivity, and loss of ignition). Ratio of active bentonite by Methylene blue test was also determined.
The results of investigations of three commercial binders applied in the Alphaset technology marked as: Sample E , Sample T and Sample S are presented in the hereby paper. These samples were subjected to the pyrolysis process at a temperature of 900°C (inert atmosphere, He 99.9999). The gas chromatograph coupled with the mass spectrometer and pyrolizer (Py-GC/MS) were used in the study. The identification of gases emitted during the thermal decomposition was performed on the basis of the mass spectral library. The obtained results indicate a certain diversification of emitted gases. Among the pyrolysis products the following harmful substances were identified: furfuryl alcohol, formaldehyde, phenol and also substances from the BTEX (benzene, toluene and ethylobezneze and xylenes) PAHs (Polycyclic Aromatic Hydrocarbons) and VOC groups (Volatile Organic Compounds). Therefore, from the environment protection point of view performing systematic investigations concerning the harmfulness of binders applied in the moulding and core sands technology, is essential.
The concept of ecosystem services becomes more and more popular in regulation of the environmental protection. One of the premises of that concept is treatment of a human and human activity as an integral part of an ecosystem. Interrelations between human activity and ecosystem can be described through the concept of ecosystem services. A certain degree of commodification of natural environment which is immanently connected with the concept of ecosystem services can become useful as a tool of assessing the impact of human activities on ecosystem as well as regulating that impact. Marine protection law is a good example of attempts to introduce the interrelated concepts of ecosystem approach and ecosystem services into functioning of the regulatory schemes.