Nizhny Novgorod State Technical University, Nizhny Novgorod, Russia:

A. N. Grachev, Assistant Professor of a Chair “Metallurgical Technologies and Equipment”, e-mail: mto@nntu.nnov.ru
I. O. Leushin, Professor, Head of a Chair “Metallurgical Technologies and Equipment”
K. A. Maslov, Assistant Professor of a Chair “Metallurgical Technologies and Equipment”
L. I. Leushina, Assistant of a Chair “Metallurgical Technologies and Equipment”

The modern conditions of severe requirements to environmental safety lead to the direction of industrial development to ecologically harmless production engineering, which priority tasks are recycling, disposal, limitation of formation and safe storage of industrial wastes. In this regard the particular importance is attached to waste recycling, development of the conception, and elaboration of process engineering solutions for use of waste products as secondary material resources for blank productions of the machine-building industry. This approach to industrial activity organization makes it possible to carry out the following operations: 1) prevent environmental contamination, 2) reduce expenses of industrial plants related to industrial waste disposal on landfill sites, 3) save raw products utilizable in the industrial production, 4) replace expensive scarce materials with less costly and readily available ones without product quality loss. This paper shows the prerequisites of utilization of salt hardening baths' sludge containing sodium and potassium chlorides as a filler in grain filters for refining aluminum melts. There are suggested the steps to prepare salt bath sludge for usage in grain filters. There is described the selection of salt bath sludge grains' size, as well as their layer thickness when charging them into the filter body. There are furnished the lab testing and industrial try-out results of the efficiency of refining silumins with grain filters using salt bath sludge grains as a filler. On the basis of the comparative analysis of cast sample mechanical properties and produced thin selection macro- and microstructure, there are made the conclusions, showing the pilot grain filter efficiency while pouring aluminum casting alloys.

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