Katalitički konverteri kao izvor platine

The increase of Platinum Group Metals demand in automotive industry is connected with growing amount of cars equipped with the catalytic converters. The paper presents the review of available technologies during recycling process. The possibility of removing platinum from the used catalytic converters applying pyrometallurgical and hyrdometallurgical methods were also investigated. Metals such as Cu, Pb, Ca, Mg, Cd were used in the pyrometallurgical research (catalytic converter was melted with Cu, Pb and Ca or Mg and Cd vapours were blown through the whole carrier). In hydrometallurgical research catalytic converters was dissolved in aqua regia. Analysis of Pt contents in the carrier before and after the process was performed by means of atomic absorption spectroscopy. Obtained result were discussed.Porast zahtjeva za materijalima iz grupe platina u automobilskoj industriji je povezan s povećanim brojem automobila opremeljenim katalitičkim konverterima. Rad prezentira pregled dostupnih tehnologija tijekom procesa recikliranja. Također je istražena mogućnost izdvajanja platine iz korištenih katalitičkih konvertera primjenom pirometalurških i hidrometalurških metoda. Metali kao Cu, Pb, Ca, Mg, Cd su korišteni pri pirometalurgijskom istraživanju (katalitički konverter je rastaljen s Cu, Pb i Ca ili s Mg i Cd parama koje se ispuhavaju kroz cijeli nosač). Kod hidrometalurgijskog istraživanja katalitički konverter je otopljen u carskoj vodici. Analiza sadržaja Pt u nosaču prije i nakon procesa je izvedena pomoću spektroskopije atomskom apsorpcijom. Dobiveni rezultati su obrazloženi

Izdvajanje metala iz grupe platina iz korištenih automobilskih katalitičkih convertera

Recycling of platinum group metals from the used auto catalytic converters is profitable from ecological and also economical point of view. This work presents the analysis of the chances of removing the platinum group metals (PGM) from the used auto catalytic converters applying pyrometallurgical and hydrometallurgical methods. The characteristics of auto catalytic converter is shown as well the available technologies used for processing the auto catalytic converters are also presented.Recikliranje metala iz grupe platina od korištenih automobilskih katalitičkih konvertera je profitabilno s ekološkog i također s ekonomskog stajališta. Ovaj rad prezentira analizu mogućnosti izdvajanja metala iz grupe platina od korištenih automobilskih katalitičkih konvertera uz primjenu pirometalurških i hidrometalurških metoda. Prikazane su karakteristike automobilskih katalitičkih konvertera kao i raspoložive tehnologije koje su korištene za obradu automobilskih katalitičkih konvertera

Modelsko istraživanje desorpcije vodika iz rastaljenog aluminija i njegovih legura

The refining process is essential for the removing undesirable hydrogen and harmful impurities from liquid aluminium and its alloys. Physical modelling allows to observe the level of refining gas dispersion in the liquid aluminium. Test stand for physical modelling of the barbotage process of aluminum for the bath reactor (URO-200) and continuous reactor (URC-7000) were built. Measurements of the oxygen removal from water were carried out as analogy of the hydrogen desorption process from liquid aluminium. In the research the distilled water saturated with the compressed oxygen was used. The level of water saturation with oxygen and then oxygen desorption from water was reached by means of the dissolved oxygen meter Elmetron CO-401.Proces rafiniranja je vrlo značajan zbog odstranjivanja nepoželjnog vodika i drugih štetnih nečistoća iz rastaljenog aluminija. Fizikalno modeliranje dopušta da se uoči razina disperzije rafiniranog plina u tekućem aluminiju. Izrađen je pristup za fizikalno modeliranje procesa rafiniranja aluminija. Mjerenja odstranjivanja kisika iz vode su provedena po analogiji procesa desorpcije vodika iz tekućeg aluminija. U istraživanju je korištena destilirana voda zasićena komprimiranim kisikom. Razina zasićenosti kisikom i desorpcija kisika iz vode je postignuta pomoću okigenometra Elmetron CO-401

Analysis of residence time distribution (RTD) curves for t-type tundish equipped in flow control devices: physical modelling

The article presents results of physical modelling of the steel continuous casting process in the tundish. Technological parameters of casting and constructive parameters of tundish were under study. Three different kinds of flow control devices were considered as well as their influence on the kinetics of steel flow and mixing in tundish. Created physical model enabled to conduct simultaneously visualization research and determine the RTD curves. According to the theory of flow in reactors the proper characteristics for estimating the flow are RTD curves E- and F-type, and they were obtained and discussed

Validation of numerical model of a liquid flow in a tundish by laboratory measurements

The article presents results of physical and numerical modelling of steel flow through a tundish of continuous casting machine. In numerical calculations the influence of mesh density was tested and the correctness of the flow description in the near-wall region was checked using Standard Wall Function model. Obtained results were verified using experimental results of velocity field (PIV method) coming from a water tundish model

Physical modelling of the process of mixing liquid metal in a tundish blown by gas

The article presents results of physical modelling of phenomena occurring during the process of blowing steel by inert gases. The aim of the research was to determine the optimal ceramic material for the porous plugs. Three different materials varying in porosity were tested. Water model of industrial tundish with nominal capacity 320 Mg was used in research. This model was made at 1:10 geometrical scale. Results of the research were presented graphically in the form of Resistance Time Distribution (RTD) curves and graphs of mixing efficiency for particular ceramic materials

The interaction of the argon curtain at the interface: metal-slag in a tundish

Due to the need to improve the quality of the produced steel, especially its metallurgical purity, attempts are made to use inert gas bubbling curtain in the tundish. The article presents the results of the research of metal-slag interaction carried out with the use of the trough-type two-strand tundish water model, made on a reducing scale – 1 : 2,5. The tundish model is built with two gas bubbling curtain. The aim of the research was to determine the optimal value of the flow rate of the blown gas, ensuring the safe course of the process taking into account the secondary contamination of liquid steel with atmospheric gases and endogenous inclusions originating from the slag

The interaction of the argon curtain at the interface: metal-slag in a tundish

Due to the need to improve the quality of the produced steel, especially its metallurgical purity, attempts are made to use inert gas bubbling curtain in the tundish. The article presents the results of the research of metal-slag interaction carried out with the use of the trough-type two-strand tundish water model, made on a reducing scale – 1 : 2,5. The tundish model is built with two gas bubbling curtain. The aim of the research was to determine the optimal value of the flow rate of the blown gas, ensuring the safe course of the process taking into account the secondary contamination of liquid steel with atmospheric gases and endogenous inclusions originating from the slag