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Abstrakt

The paper, especially dealt with problems of reclamation of used furan sand, carried out in new, vibratory sand reclamation unit REGMAS developed by researches from AGH-University of Science and Technology, Faculty of Foundry Engineering in Cracow (Poland). Functional characteristics of reclamation unit as well as the results of reclamation of used sand with furfuryl resin are discussed in the paper. The quality of reclaim was tested by means of the LOI and pH value, dust content in the reclaim and at least by the the quality of the castings produced in moulds prepared with the use of reclaimed matrix.
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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 Outtokumpuja Company in HM Głogów 2, after the copper removal performed according the new technology (Sample S3). In practice, all tested slags satisfy the allowance criteria of storing on the dumping grounds of wastes other than hazardous and neutral.
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Due to the presence of harmful substances in resins those mould sands may be hazardous to the natural environment and workers. The general assessment of harmfulness of sands used for molds and cores encompasses 2 basic points: emission of hazardous substances during processes of preparing sands, pouring mold with liquid metals (high temperatures), cooling and shaking-out; possibility of washing out hazardous substances from used sands to the environment, during storage or economic use outside foundries. We present the results of research on the emission of BTEX compounds from mould sands with phenolic resins during pouring liquid metal of different temperature (cast iron and Al alloy). The research was conducted according to the original method prepared by the authors, which has been used for years in cooperation with various foundries (Poland, abroad).
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Due to the presence of harmful substances in resins those mould sands may be hazardous to the natural environment and workers. The general assessment of harmfulness of sands used for molds and cores encompasses 2 basic points: emission of hazardous substances during processes of preparing sands, pouring mold with liquid metals (high temperatures), cooling and shaking-out; possibility of washing out hazardous substances from used sands to the environment, during storage or economic use outside foundries. We present the results of research on the emission of BTEX compounds from mould sands with phenolic resins during pouring liquid metal of different temperature (cast iron and Al alloy). The research was conducted according to the original method prepared by the authors, which has been used for years in cooperation with various foundries (Poland, abroad).
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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.
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Nature reserves are one of the most important measures in saving biodiversity, however, during the climate change, a real danger arises, that these territories would not be able to fulfill the objectives. In order to mitigate negative effects of climate change in protected areas it is necessary to create and apply management programs, based on future ecosystems needs. The main aim of presented study was to evaluate sensitivity of rare and vulnerable species to climate change in order to suggest measures for better management of nature reserves in the future. According to scientific literature, 12 biological and ecological plant characteristics determining sensitivity of species (limiting factors) have been detected. 73 plant species that are protected in Lithuanian reserves were evaluated qualitatively according to limiting factors of climate change. As the result, it was offered to apply additional protection measures to 47 species in the light of climate change. Groups of plant species that should be affected highly negatively or highly positively were identified. 16% of plant species protected in nature reserves were evaluated as very sensitive to climate change and the condition of these plants may worsen. On the other hand, 14 plant species were given as least sensitive to negative effects and future climate is more favorable to species growth and spread than the existing. The highest danger is predicted for Silene chlorantha (Willd.) Ehrh., and the best condition is predicted for Mentha longifolia (L.) Huds. Dactylorhiza incarnata (L.) Soó. The study also gives recommendations for the protection of rare plants in the future. Different management measures are taken into account: mitigation of the direct effect of climate change (I), improvement of an existing level of rareness (II), respecting the relation to physical and biological environment (III), consideration of spread and geographical limits (IV). Three management intensity levels were suggested according to species sensitivity.
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The impulse noise is agent harmful to health not only in the case of shots from firearms and the explosions of explosive materials. This kind of noise is also present in many workplaces in the industry. The paper presents the results of noise parameters measurements in workplaces where four different die forging hammers were used. The measured values of the C-weighted peak sound pressure level, the A-weighted maximum sound pressure level and A-weighted noise exposure level normalized to an 8 h working day (daily noise exposure level) exceeded the exposure limit values. For example, the highest measured value of the C-weighted peak sound pressure level was 148.9 dB. In this study possibility of the protection of hearing with the use of earplugs or earmuffs was assessed. The measurement method for the measurements of noise parameters under hearing protection devices using an acoustical test fixture instead of testing with the participation of subjects was used. The results of these measurements allows for assessment which of two tested earplugs and two tested earmuffs sufficiently protect hearing of workers in workplaces where forging hammers are used.
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Verification of electrical safety in low-voltage power systems includes the measurement of earth fault loop impedance. This measurement is performed to verify the effectiveness of protection against indirect contact. The widespread classic methods and meters use a relatively high value of the measuring current (5#4;20) A, so that they are a source of nuisance tripping of residual current devices (RCDs). The meters dedicated to circuits with RCDs usually use an extremely low value of current (lower than 15 mA), which in many cases it is not acceptable in terms of the measurement accuracy. This paper presents a method of earth fault loop impedance measurement in 3-phase circuits, without nuisance tripping of RCDs – the concept of measurement, the meter structure and the experimental validation. The nuisance tripping is avoided in spite of the use of measuring current value many times higher than that of the rated residual current of RCDs. The main advantage of the proposed method is the possibility of creating values of measuring current in a very wide range, what is very important with regard to accuracy of the measurement.
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The situation when groundwater considerably rises above the “normal” level, water intake, lowering of groundwater levels and other relevant practical tasks require the drainage facilities. The most effective techniques of numerical studies of the corresponding boundary problems at present time are methods of dealing with inverse boundary value problems (conformal and quasi-conformal mappings). As basis of this research we used the case of combining the fictitious domain methods with quasi-conformal mappings of the solution of nonlinear boundary value problems for the calculation of filtra-tion regimes in environments with free boundary areas (depression curves) and zones of “mountainous” areas. This paper reviews the stationary issue of flat-vertical stationary non-pressure liquid filtration to horizontal symmetric drainage. In the paper a practical methodology for solving boundary value problems on conformal mappings is suggested for the calculation of the filtration process in the horizontal symmetrical drainage. The idea of block iterative methods was used during the creation of the corresponding algorithm which is based on the alternating “freeze” of the anticipated conformance parameter, the internal and boundary connections of the curvilinear area. The results of the conducted numerical calculations confirmed the effectiveness of the suggested problem formulations and algorithms of their numerical solution and the possibility of their use in the modelling of nonlinear filtration processesoccurring in horizontal drainage systems, as well as in the design of drainage facilities and optimizing other hydrosystems. Therefore these results are of great importance.
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The results of the efficiency of the primary reclamation process as well as the influence of the used sand temperature and other process parameters on it are presented in this paper. A separate stand realized on a reduced scale was built, which is an analogous process of the primary reclamation treatment of spent foundry sands. The used sands were introduced to the crushing process in an agglomerated form in the way typically used in industrial devices. The primary reclamation process was realized on a set of four horizontal sieves with decreasing mesh clearances while maintaining their geometrical dimensions applied in the Regmas industrial device. The model system consists of a vibratory drive mounted on the table, allowing us to control the supply frequency of the vibratory motors within a range of 40-60 Hz as well as the computer system for measuring the vibration parameters and drive power. The used sand on the quartz matrix with the KALTHARZ U404 resin and 100T3 hardener was used in our investigations. The used sand was prepared under the following conditions: cubic-shaped elements made of the applied furan sand was compacted by vibrations then hardened and subjected to heating under controlled conditions (as a “simulation” of the overheating process taking place in the mold after pouring). Time functions of the crushing and sieving process in dependence of the overheating degree of the reference sand samples (100°, 200°, and 300°C) were investigated at various table vibration frequencies and feed loads of the sieve set. The relative index of the crushing ability was determined.
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Theory and practice of environmental protection in the case of foundries in Europe and Asia • Experience resulting from the cooperation with the foundries in a few European countries, China and India • Phenomena and factors affecting the pollution of the natural environment and the implementation of measures aiming at the environmental protection Every specialist dealing with foundry processes and their impact on environmental pollution must have encountered in their professional careers numerous situations in which the theory of environmental protection confronts the stark reality. The discrepancy between theory and practice can particularly be noticed in foundry engineering in developing countries where the contrasts between different countries and casting plants are extremely striking. The comparison of working conditions in European and Asian foundries provides a vast scope for further observations and analyses. Environmental protection seems not only a concern of manufacturers of castings, but also of their customers whose opinion exerts a significant influence on both the acceptability of working conditions and on the approach to environmental pollution adopted in metal casting industry. The article presents a number of examples of various outlooks on environmental issues in foundries manufacturing a wide range of cast steel and cast iron castings, where different technologies and production processes are applied.
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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.
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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.
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The problem related to the management of post reclamation dusts generated in the reclamation process of waste moulding sands with organic binders is presented in the hereby paper. Waste materials generated in this process are products hazardous for the environment and should be utilised. The prototype stand for the utilisation of this dangerous material in its co-burning with coal was developed and patented in AGH in Krakow. The stand was installed in one of the domestic casting houses. As the utilisation result the transformed waste product is obtained and its management in the production of ceramic materials constitutes the subject of the presented publication.
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Foundry dust from blasting and grinding of castings contain a high amount of iron, ergo it is possible its recycling in foundry process. Dust was compacted by briquetting, two kinds of briquettes were prepared (A contained 95% magnetic part of dust from casting blasting +5% bentonite and B contained 95% mixture of dust from casting grinding and magnetic part of dust from casting blasting + 5% bentonite) and used as a part of charge into the electric induction furnace. It was found that addition of briquettes has had an influence of a chemical composition of cast iron above all on content of sulphur, phosphorus and silicon. It was not reflected in decrease in tensile strength and in microstructure. Yield of metal from briquettes was not lower then 70%.
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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.
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Mechanical reclamation process of spent moulding sands generate large amounts dusts containing mainly rubbed spent binding agents and quartz dust. The amounts of post-reclamation dusts, depending of the reclamation system efficiency and reclaim dedusting system, can reach 5 -10% in relation to the total reclaimed moulding sand. This dust due to the high content of the organic substances is a threat to the environment and therefore requires the storage on landfills specially adapted for this type of waste. On the other hand, the presence of organic substances causes that these dusts have relatively high energy values that could be used. However, at present there is no coherent, environmentally friendly concept for the management of this type of dust. The paper presents the results of tests of thermal utilization the dusts (as a source of energy) were carried out at AGH University of Science and Technology. Thermal utilization of dusts was carried out in the co-burning with carbon carriers process or in individual burning (Patent PL 227878 B1 and patent application PL - 411 902).
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Organic binders applied in foundry plants based on synthetic resins, from the one side influence obtaining the required technological properties by the moulding sand and – in consequence – obtaining good quality castings, and on the other side are the source of volatile organic compounds (VOC). Together with synthetic resins their hardeners, which although added in very small amounts emit during their thermal decomposition substances negatively influencing the natural environment, are also used. Both, resins and hardeners only at the influence of high temperatures accompanying moulds pouring with liquid metal generate harmful volatile organic compounds including compounds from the BTEX group. Investigations of the temperature influence on the kind and amount of organic compounds formed during the thermal decomposition of selected binders and hardeners and their mixtures allow to determine temperature ranges the most favourable for emitting harmful substances as well as to compare their emission from the selected materials. The aim of this study was the determination the temperature influence on formation substances from the BTEX group, during thermal decomposition of the selected binder, its hardener and their mixture. The BTEX group emission constitutes one of the basic criteria in assessing the harmfulness of materials applied for moulding and core sands and it can undergo changes in dependence of the applied system resin-hardener. Investigations were carried out on the specially developed system for the thermal decomposition of organic substances in the temperature range: 5000 C – 13000 C, at the laboratory scale. The investigations subject was the furan resin, its hardener and hardened furan resin. The assessment of the emission degree of the BTEX group in dependence of the system subjected to the temperature influence was performed, within the studies. The temperature range, in which maximal amounts of benzene, toluene, ethylbenzene and xylenes were emitted from tested materials – was defined. The qualitative and quantitative analysis of the BTEX group were carried out with using the gas chromatography technique coupled with the mass spectrometry (GC/MS).
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The investigation results of the reclamation of spent moulding sands with furfuryl resin are presented in this paper. The reclamation process was performed in the secondary reclamation chamber of the REGMAS 1.5 vibratory reclaimer. 70 kg portions of moulding sands, previously subjected to the primary reclamation and dedusting, were used. The secondary reclamation was performed in two stages: the first consisted of determining the reclaimer intensity at various reclamation times (5 min, 10 min and 15 min) and various electrovibrator frequencies (40 Hz, 50 Hz and 60 Hz), the second consisted of determining the influence of additional crushing elements on the intensity of processes.
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In this article, an outline of the key questions connected with the essential problems of energy-consumption of air-stream moulding machines has been presented. Research results and calculations of requisite parameters appraisable of energy-consumption of air-stream moulding machines have been supplemented also by the data analysis of offer of the moulding machines manufacturers. The attention on constructional and technological factors which are favourable for the diminution of energy-consuming of the moulding process has been paid.
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The substrates to biogas production in anaerobic digestion, except plant materials, can also be animal feces and manure. It should be highlighted that Poland is one of leaders in the European Union in animal breeding. However, there is no precise data in the literature on the potential of biogas production from animal feces in this country. The aim of the paper was to analyze the biogas production potential from manure in Poland. The aim of work included anaerobic digestion research following materials: cow manure, pig manure, poultry manure and sheep manure. In the next step, based on the obtained results of the biogas yield, energy potential calculations were made. The methane yield for the investigated feedstock materials in the batch culture technology was performed following the internal procedures developed based on the adapted standards, i.e. DIN 38 414-S8 and VDI 4630. Animal wastes were obtained from the Agricultural Experimental Stations of Poznan University of Life Sciences (Poznan, Poland). On a base of achieved results it was concluded that tested substrates have a high energy potential (approx. 28.52 GWh of electricity). The largest potential for electricity production was found in chicken manure (about 13.86 GWh) and cow manure (about 12.35 GWh). It was also shown which regions of Poland have the best chance for development of agriculture biogas plants (Wielkopolskie and Mazowieckie voivodships) and where the potential is the least (Lubuskie and Opolskie voivodeships).
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Since late 2011, porcine infections with highly virulent and antigenic variant of pseudorabies virus (PRV) cause great economic loss in the swine industry in China, and its emergence leads to variable protection efficacy of the commercially available PRV vaccine. In the present study, the potential cross-protective efficacy of two live virus vaccines, includ- ing a commercial vaccine, and an attenuated low pathogenic PRV variant (rPRVTJ-delTK/gE/gI) against a PRV variant Tianjing (TJ) was evaluated in piglets. Vaccination of piglets with the live vaccine Bartha-K61 could not reduce the clinical signs, and was partially efficacious in the reduc- tion of viral loads upon PRV variant TJ challenge, indicating that this live vaccine provided limited cross-protection efficacy against the PRV variant infection. Additionally, rPRVTJ-delTK/gE/gI appeared to exert some beneficial efficiency in shortening the period of clinical fever and improv- ing the growth performance of the challenged pigs. Our findings give a valuable guidance for the choice and use of PRV vaccines to control PRV variant infection in the field.
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The main objective of this work was to present a successful stabilization action of a building structure in an active landslide. Firstly, history of the case and a FEM simulation explaining ensuing situation are presented. Then different structural measures to stabilize the whole system are discussed. The structural solution of the problem (pile system reaching solid rocky zone) is presented in more detailed way. The estimation of forces acting on the structure, caused by an unstable soil mass, being crucial for the design of stabilizing structure is described.
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The excessive use of pesticides is a problem in most parts of the world today because of their broad and unspecific target range that is considerably harmful. The accumulation of several chemical insecticide residues based on chlorpyrifos-methyl, organochlorine, different isomers of HCH, DDT etc., in Triticum aestivum L. plants can be dangerous. Hence, there is an urgent need to develop potential and safer alternative measures. Wheat (Triticum aestivum L.) is a major cereal crop grown and used for food, animal feed, beverages and furniture accessories in most parts of the world. It also serves as a host to various insect pests. Our previous studies showed the insecticidal potency and specificity of short ssDNA oligonucleotides from the inhibitor of apoptosis (IAP-2 and IAP-3) genes of Lymantria dispar multicapsid nuclear polyhedrosis virus (LdMNPV) against gypsy moth (L. dispar) larvae, a possible insect pest of non-host plants like wheat. Consequently, the present study analyzes the effects of ssDNA oligonucleotides used as DNA insecticides on wheat (T. aestivum) plant biomass, plant organs and some biochemical parameters as a marker of the safety margin on non-target organisms. The results obtained on plant biomass showed that groups treated with ssDNA oligonucleotides at concentrations of 0.01 pmol · μl−1, 0.1 pmol · μl−1 and 1 pmol · μl−1 varied in comparison with the control group, but remained harmless to plant growth and development, while the treatment concentration of 0.001 pmol · μl−1 did not affect the plant biomass. The glucose, protein and phosphorous biochemical parameters, analyzed after 21 days, showed that the ssDNA oligonucleotides used were equally safe. The data obtained for the plant organs (leaves and root lengths) indicate that the phenomenon of DNA insecticides can be further studied and developed for plant protection while improving the growth of plant organs even for a non-target organism such as wheat T. aestivum plants.
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Archives of Environmental Protection is the oldest Polish scientifi c journal regarding environmental engineering and protection. It has been published by the Institute of Environmental Engineering of PAS in Zabrze since 1975. The Committee on Environmental Engineering of PAS became its co-publisher in 2011. The quarterly publishes original articles (earlier, also announcements) concerning broadly understood areas of the environmental engineering and protection. The subjects include: air, land and water protection; technologies of fl ue gases, soil and wastewater treatment; transformations and transportation of pollutants in the environment; measurement techniques used in research and engineering as well as environmental monitoring. The published articles also focus on the reclamation and management of derelict lands, environmental management and other questions related to the environmental engineering and protection. The journal has been abstracted by Thomson Scientific since 2006 in the following databases: Science Citation Index Expanded, Biological Abstracts and BIOSIS Previews. Moreover, the journal was given the impact factor (IF) in 2010. The following article presents statistical data as well as a brief history and description of the journal.
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