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.
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.
The investigation results of the influence of the reclaim additions on the properties of moulding sands with the GEOPOL geopolymer
binder developed by the SAND TEAM Company were presented. Two brands of hardeners were applied in the tested compositions, the
first one was developed by the SAND TEAM Company, marked SA72 and the new hardener offered by the KRATOS Company, marked
KR72. The main purpose of investigations was to determine the influence of reclaim fractions and the applied hardener on the basic
moulding sands properties, such as: bending and tensile strength, permeability and grindability. The unfavourable influence of the reclaim
additions into moulding sands on the tested properties as well as an increased hardening rate, were found. Moulding sands, in which the
hardener KR72 of the KRATOS Company was used, were less sensitive to the reclaim additions.
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).
The results of investigations of moulding sands with an inorganic binder called GEOPOL, developed by the SAND TEAM Company are
presented in the paper. Hardeners of various hardening rates are used for moulding sands with this binder. The main aim of investigations
was determination of the influence of the hardening rate of moulding sands with the GEOPOL binder on technological properties of these
sands (bending strength, tensile strength, permeability and grindability). In addition, the final strength of moulding sands of the selected
compositions was determined by two methods: by splitting strength and shear strength measurements. No essential influence of the
hardening rate on such parameters as: permeability, grindability and final strength was found. However, the sand in which the slowest
hardener (SA 72) were used, after 1 hour of holding, had the tensile and bending strength practically zero. Thus, the time needed for taking
to pieces the mould made of such moulding sand will be 1.5 - 2 hours.
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.
The furan resin offers advantages such as high intensity, low viscosity, good humidity resistance and is suitable for cast different casting
alloys: steel, cast iron and non-ferrous metal casting. For hardening furan resins are used different hardeners (acid catalysts). The acid
catalysts have significant effects on the properties of the cured binder (e,g. binding strength and thermal stability) [1 - 3]. Investigations of
the gases emission in the test foundry plant were performed according to the original method developed in the Faculty of Foundry
Engineering, AGH UST. The analysis is carried out by the gas chromatography method with the application of the flame-ionising detector
(FID) (TRACE GC Ultra THERMO SCIENTIFIC).
A determination of the heating degree of the moulding sand with bentonite on the grounds of simulating investigations with the application of the MAGMA program, constitutes the contents of the paper. To this end the numerical simulation of the temperature distribution in the virtual casting mould was performed. It was assumed that the mould cavity was filled with a moulding sand with bentonite of a moisture content 3,2 % and bentonite content 8 %. A computer simulation can be used for predicting the heating degree of moulding sands with bentonite. Thus, prediction of the active bentonite (montmorillonite) content in individual layers of the overheated moulding sand can be done by means of the simulation. An overheating degree of a moulding sand with bentonite, and thus the bentonite deactivation depends on a temperature of a casting alloy, casting mass, ratio of: masssand : masscasting, moulding sand amount in the mould and contact area: metal – mould (geometry of the casting shape). Generally it can be stated, that the bentonite deactivation degree depends on two main factors: temperature of moulding sand heating and time of its operation.
A special Slag-Prop Cu database has been developed to archive data from laboratory and industrial tests related to post-reduction slags. In
order to enrich the data areas, it was decided to design a system for measuring the temperature of the liquid slag and its viscosity. Objectives
of research work are to gather information on the properties of post-slags such as the temperature of liquid slag and its viscosity. The
discussed issues are especially important in the foundry practice. Designed research stand and using of database applications can greatly
facilitate the work of metallurgists, foundrymen, technologists and scientists. The viscosity measurement was developed and presented
earlier. The author's analytical methodology was supplemented by a thyristor measuring system (described in the article). The system
temperature measurement can be performed simultaneously in 3 ways to reduce the measurement error. Measurement of the voltage mV -
using the Seebeck effect can be measured throughout the entire range of thermocouple resistance, up to 1300 °C. Direct temperature
measurement ⁰C - measurement only below 1000 ⁰C. Additional measurement - the measurement can also be read from the pyrometer set
above the bath. The temperature and the reading frequency depend on the device itself. The principle of measurement is that in a molten
metal / slag crucible, we put a N-type thermocouple. The thermocouples are hung by means of a tripod above the crucible and placed in a
crucible. The thermocouple is connected to a compensating line dedicated to this type of thermocouple. The cable is in turn connected to a
special multimeter that has the ability to connect to a computer and upload results. Temperature measurement can be performed
simultaneously in 3 ways to reduce the measurement error. The Sn-Pb alloy has been subjected to testing for proper operation of the device.
In this foot should be observed the supercooling of the liquid, which initiates the crystallization process and in which latent heat begins to
exude raising the temperature until the coagulation temperature is reached.
Suitability of the given binding agent for the moulding sands preparation depends on the one hand on the estimation of technological properties of the sand and the mould made of it and the obtained casting quality and on the other hand on the assessment of this sand influence on the natural and working environment. Out of moulding sands used in the foundry industry, sands with organic binders deserve a special attention. These binders are based on synthetic resins, which ensure obtaining the proper technological properties and sound castings, however, they negatively influence the environment. If in the initial state these resins are not very dangerous for people and for the environment, thus under an influence of high temperatures they generate very harmful products, being the result of their thermal decomposition. Depending on the kind of the applied resin (phenol-formaldehyde, urea, furfuryl, urea–furfuryl, alkyd) under an influence of a temperature such compounds as: furfuryl alcohol, formaldehyde, phenol, BTEX group (benzene, toluene, ethylbenzene, xylene), and also polycyclic aromatic hydrocarbons (PAH) can be formed and released. The aim of the study was the development of the method, selection of analytical methods and the determination of optimal conditions of formation compounds from the BTEX group. An emission of these components constitutes one of the basic criteria of the harmfulness assessment of binders applied for moulding and core sands. Investigations were carried out in the specially designed set up for the thermal decomposition of organic substances in a temperature range: 5000 C – 13000 C at the laboratory scale. The object for testing was alkyd resin applied as a binding material for moulding sands. Within investigations the minimal amount of adsorbent necessary for the adsorption of compounds released during the decomposition of the resin sample of a mass app. 15 mg was selected. Also the minimal amount of solvent needed for the desorption of compounds adsorbed in the column with adsorbent was found. The temperature range, in which the maximal amounts of benzene, toluene, ethylobenzene and xylenes are released from the resin, was defined. The qualitative and quantitative analyses of compounds from the BTEX group were performed by means of the gas chromatography combined with the mass spectrometry (GC/MS).
Production processes at KGHM are complex and require from customers products of constantly higher quality at relatively lowest prices. Such situation results in an increase of the importance of optimisation of processes. As products and technologies change rapidly, technologists at the plant in Głogów have less time to achieve optimisation basing on own experiences. Analysing a particular process, we can e.g. detect occurring disturbances, find factors having an influence on quality problems, select optimal settings or compare various production procedures. Analysis of the course of production process is the basis of process optimisation. One optimisation in case of the process of decopperisation of flash slag can be a change of a technological additive to a less energy-consuming one, and its final result can be an improvement of the productivity index, a change of the relation between final effects and born expenditures, as well as optimisation of production costs.