Automotive catalytic converters have a limited life time, after which the catalyst must be replaced or regenerated. The spent catalytic converters contain small amount of precious metals. Recovery of these metals is essential for environmental and economic reasons. The waste electronic equipment is also an attractive source for recovery of precious metals. Precious metals in electronic scraps are concentrated mainly in printed circuits and integrated circuits - so generally in elements that are the most diverse in their composition. Material heterogeneity of these elements is the reason why there is no universal method for processing this type of scrap. Methods used in the world for recovery of precious metals from spent auto catalytic coverters and electronic wastes by pyrometallurgical and hydrometallurgical methods were mentioned in this paper. The results of simultaneous melting of electronic waste with spent automotive catalysts were presented. The printed circuit boards were used as the carrier and as a source of copper. The precious metals present in the catalyst were collected in copper.

Hitherto existing investigations concerning the ceramic filter use in the steel making processes (both of laboratory and industrial scale) have given good results. The obtained results of filtration (in the industrial) have proved that this method may be used as an effective and cheap way of steel filtration from non-metallic inclusions. Placing filters in the tundish is the best location in consideration of limiting the possibility of secondary pollution of steel. Yet, the results presented in this paper, of an experiment prepared and carried out in the industrial environment, are the only positive results obtained, which are connected with so much quantities of liquid steel processed with use of the multi-hole ceramic filters.

The research on the process of steel filtration from non-metallic inclusions is currently entering the last phase of industrial experiments. Their positive effects confirm the previous theoretical assumptions and laboratory tests. The application of steel filtration as a permanent technological operation in the process of steel casting will remarkably improve its metallurgic purity. An additional advantage will be diminishing the probability of covering the outlet nozzle of a tundish. This paper presents an outline of the experiment results mentioned above.

Electric arc furnaces are commonly used in foamed slag technology for the production of steel from steel scrap through an electric process. The effects of using this technology include increased efficiency, reduced consumption of refractory materials, reduced energy consumption, reduced electrode wear, and improved arc stability. The world is constantly looking for solutions to optimize the feeding of the foaming agent to the electric furnace, including determining the moment of starting its feeding. The authors propose using two parameters to determine the optimal moment of introducing the foaming agent: the change in the sound level emitted by the arc furnace and the fluctuations in active power consumption. In order to determine the above parameters, tests were carried out on an industrial alternating UHP arc furnace with a capacity of 70 tons. The sound intensity level was determined at which the feeding of the foaming agent to the furnace’s working space should begin. A moving coefficient of power consumption variation was developed and decision variables of the software for online foaming agent feeding were determined. As a result of implementing the developed solutions to the electric furnace control system and conducting comparative tests, savings were obtained in the form of reduced foaming agent consumption.