The suspension of copper droplets in the slag is considered. The copper/slug suspension is delivered as the product from the direct-toblister
process which is applied in the KGHM – Polska Miedź (Polish Copper) S.A. factory. The droplets / slag suspension was treated by
a special set of reagents (patented by the authors) to improve the coagulation process. On the other hand, the observations are made to
estimate if the melting / reduction process in the furnace is sufficiently effective to avoid a remaining of carbon in the copper droplets.
The coagulation process was carried out in the crucible (laboratory scale). However, conditions imposed to the coagulation / solidification
process in the laboratory scale were to some extent similar to those applied usually in the industry when the suspension is subjected to the
analogous treatment in the electric arc-furnace. Some suggestions are formulated how to improve the industrial direct-to-blister process.
This article contains information concerning of the analysis the possibility of defining refinery qualities of the slag based thermo-physical
and thermo-dynamical data. It was showed the brass refining with the many-carbide reagents introduced in to the slag. The paper presents
the results of the structure analysis of the brass after carbide slag refining in the industrial conditions. The results of the macrostructure
analysis have confirmed the argument on high reducing effectiveness of manganese and aluminium carbide used during CuZn39Pb2 alloy
melting. The X-Ray microanalysis of the ingot cross-section has shown considerable discrepancies in the disposition of the inclusions.
This effects showed on the great influence of reduction melting condition in to the brass melting
The article presents an integrated analytical and measurement system for evaluation of the properties of cast metals and alloys. The presented platform is an extension of the SLAG - PROP application with new modules, which allow to use information on metallurgical processes in an even more effective way, as well as to evaluate the finished product. In addition, the construction of a measuring station for the analysis of thermal processes taking place in a metal bath allows for precise observation of phenomena together with their appropriate interpretation. The article presents not only the cooling curves of certain copper alloys. The analysis also covered mechanical properties related to hardness, finished products depending on the mold in which the products were cast. In the literature one can find information about the mechanical properties of products in the improved state, usually after plastic or thermal treatment, omitting their properties obtained as a result of a naturally made casting. The article also presents the method of placing information in the database using a convenient graphical tool.
The article describes the optimization of the melting brass. Brasses, as one of the most popular alloys of copper, deserve special attention
in the context of the processes of melting, which in turn would provide not only products of better quality, but also reduce the cost of their
production or refining. For this purpose, several studies carried out deriatographic (DTA) and thermogravimetric (TG) using
derivatograph. The results were confronted with the program SLAG - PROP used to evaluate the physicochemical properties of the
coatings extraction. Based on the survey and analysis of the program can identify the most favorable physico - chemical properties, which
should be carried out treatments. This allows for slag mixtures referred configurations oxide matrix containing specific stimulators of the
reaction. Conducted empirical studies indicate a convergence of the areas proposed by the application. It should also be noted that the
program also indicates additional areas in which to carry out these processes would get even better, to optimize the melting process, the
results.
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.
This paper presents the idea of increasing the effectiveness of slag decopperisation in an electric furnace in the "Głogów II" Copper Smelter by replacing the currently added CaCO3with a less energy-intensive technological additive. As a result of this conversion, one may expect improved parameters of the process, including process time or power consumption per cycle. The incentives to optimize the process are the benefits of increasing copper production in the company and the growing global demand for this metal. The paper also describes other factors that may have a significant impact on the optimization of the copper production process. Based on the literature analysis, a solution has been developed that improves the copper production process. The benefits of using a new technology additive primarily include increased share of copper in the alloy, reduced production costs, reduced amount of power consumed per cycle and reduced time it takes to melt. At the conclusion of the paper, the issues raised are highlighted, stressing that mastering the slag slurry process in electric furnaces requires continuous improvement.
Discusses an attempt to optimize the operation of an electric furnace slag to be decopperisation suspension of the internal recycling
process for the production of copper. The paper presents a new method to recover copper from metallurgical slags in arc-resistance electric
furnace. It involves the use of alternating current for a first period reduction, constant or pulsed DC in the final stage of processing. Even
distribution of the electric field density in the final phase of melting caused to achieve an extremely low content of metallic copper in the
slag phase. They achieved by including the economic effects by reducing the time reduction.
The post-processing slags containing about 0.8 wt.% of copper were subjected to the treatment of a complex reagent. The chemical composition of the complex reagent has been elaborated and patented in frame of the Grant No. PBS3/A5/45/2015. The slags had an industrial origin and were delivered by the Smelter and Refinery Plant, Głogów, as a product of the direct-to-blister technology performed in the flash furnace assisted by the arc furnace. An agglomeration of copper droplets suspended in the liquid slag, their coagulation, and deposition on the bottom of furnace were observed after the treatment this post-processing slag by the mentioned reagent. The treatment of the post-processing slags by the complex reagent was performed in the arc furnace equipped with some additional electrodes situated at the furnace bottom (additional, in comparison with the arc furnace usually applied in the Smelter and Refinery Plant, Głogów). The behaviour of the copper droplets in the liquid slag within the competition between buoyancy force and gravity was studied from the viewpoint of the required deposition of coagulated copper droplets. The applied complex reagent improves sufficiently the surface free energy of the copper droplets. In the result, the mechanical equilibrium between coagulated copper droplets and surrounding liquid slag is properly modified. Eventually, sufficiently large copper droplets are subjected to a settlement on the furnace bottom according to the requirements. The agglomeration and coagulation of the copper droplets were significantly improved by an optimized tilting of the upper electrodes and even by their rotation. Moreover, the settlement was substantially facilitated and improved by the employment of both upper and lower system of electrodes with the simultaneous substitution of the variable current by the direct current.
The suspension of the copper droplets in the post-processing slag taken directly from the KGHM-Polska Miedź S.A. Factory (from the
direct-to-blister technology as performed in the flash furnace) was subjected to the special treatment with the use of the one of the typical
industrial reagent and with the complex reagent newly patented by the authors. This treatment was performed in the BOLMET S.A.
Company in the semi-industrial conditions. The result of the CaCO3, and Na2CO3 chemicals influence on the coagulation and subsequent
sedimentation of copper droplets on the crucible bottom were subjected to comparison with the sedimentation forced by the mentioned
complex reagent. The industrial chemicals promoted the agglomeration of copper droplets but the coagulation was arrested / blocked by
the formation of the lead envelope. Therefore, buoyancy force forced the motion of the partially coagulated copper droplets towards the
liquid slag surface rather than sedimentation on the crucible bottom. On the other hand, the complex reagent was able to influence the
mechanical equilibrium between copper droplets and some particles of the liquid slag as well as improve the slag viscosity. Finally, the
copper droplets coagulated successfully and generally, were subjected to a settlement on the crucible bottom as desired / requested.
A vertical cut at the mid-depth of the 15-ton forging steel ingot has been performed by curtesy of the CELSA – Huta Ostrowiec plant.
Some metallographic studies were able to reveal not only the chilled undersized grains under the ingot surface but columnar grains and
large equiaxed grains as well. Additionally, the structural zone within which the competition between columnar and equiaxed structure
formation was confirmed by metallography study, was also revealed. Therefore, it seemed justified to reproduce some of the observed
structural zones by means of numerical calculation of the temperature field. The formation of the chilled grains zone is the result of
unconstrained rapid solidification and was not subject of simulation. Contrary to the equiaxed structure formation, the columnar structure
or columnar branched structure formation occurs under steep thermal gradient. Thus, the performed simulation is able to separate both
discussed structural zones and indicate their localization along the ingot radius as well as their appearance in term of solidification time.
This article discusses issues related to continuous casting of brass. The tested material was CuZn39Pb2 brass with the use of continuous casting and different parameters of the process. The position consists of a melting furnace with a graphite refining pot of about 4000 cm3 chuting capacity, a graphite crystallizer of 9,5 mm nominal diameter, a primary and secondary cooling system and an extracting system as well. The analysis was carried out in terms of technological parameters of the process and type of charge. Highlighted: feedrate ingot, number of stops, and technological temperatures. The surface quality of the obtained ingots and the structure were analyzed. The most favorable conditions were indicated and technological recommendations indicated. They have been distinguished for ingots for plasticity and other technologies. Favorable casting conditions are low feed and low temperature. Due to the presence of impurities coming from the charge it is disadvantageous to have Ni greater than 0.053% by mass, and Fe more than 0.075% by mass. It is recommended to maintain a high zinc content in the melt which is associated with non-overheating of the metal during casting and earlier melting.
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.
Some metallographic studies performed on the basis of the massive forging steel static ingot, on its cross-section, allowed to reveal the
following morphological zones: a/ columnar grains (treated as the austenite single crystals), b/ columnar into equiaxed grains
transformation, c/ equiaxed grains at the ingot axis. These zones are reproduced theoretically by the numerical simulation. The simulation
was based on the calculation of both temperature field in the solidifying large steel ingot and thermal gradient field obtained for the same
boundary conditions. The detailed analysis of the velocity of the liquidus isotherm movement shows that the zone of columnar grains
begins to disappear at the first point of inflection and the equiaxed grains are formed exclusively at the second point of inflection of the
analyzed curve. In the case of the continuously cast brass ingots three different morphologies are revealed: a/ columnar structure, b/
columnar and equiaxed structure with the CET, and c/ columnar structure with the single crystal formation at the ingot axis. Some
forecasts of the temperature field are proposed for these three revealed morphologies. An analysis / forecast of the behavior of the
operating point in the mold is delivered for the continuously cast ingot. A characteristic delay between some points of breakage of the
temperature profile recorded at the operating point and analogous phenomena in the solidifying alloy is postulated.
There are presents the internal recycling in anode furnace, in addition to mainly blister copper and converter copper. During the process
there arise the two types of semi-finished products intended for further pyro metallurgical processing: anode copper and anode slag. The
stream of liquid blister copper enters into the anode furnace treatment, in which the losses are recovered, e.g. copper, resulting from
oxidation and reduction of sulfides, oxides and the oxidation of metallic compounds of lead, zinc and iron. In the liquid phase there are
still gaseous states, which gives the inverse relationship relating to the solid phase, wherein the gases found an outlet in waste gas or
steam. The results of chemical analysis apparently differ from each other, because crystallite placement, the matrix structure and the
presence of other phases and earth elements are not compared, which can be regained in the process of electrorefining. One should not
interpret negatively smaller proportion of copper in the alloy, since during the later part of the production more elements can be obtained,
for example from sludge, such as platinum group metals and lanthanides. According to the research the quality of blister copper, to a large
extent, present in the alloy phase to many other elements, which can be recovered.