Powder pneumatic injection as a tool for wastes utilization

Purpose: Metallurgical process generates many solid, gaseous and liquid wastes. Nowadays when environmental protection is one of the most important problems and when pollution limits are very tight as well, problem of the metallurgical wastes is a strategic one. Design/methodology/approach: In present days the metallurgical and foundry plant have to utilize their own wastes, especially these which are the most dangerous and toxic or have to render harm of its and transfer to another industry branch for further utilization. Nowadays the issue of wastes management has the place both in industrial practice and scientific field too. The presented work is a result of such an approach, where a cooperation between scientific and industrial partners gives good economical and ecological results. Findings: One of the very efficient method of utilization of furnace dusts from any melting furnace or the finest fractions of charging materials is pneumatic powder injection directly into molten metal bath.The method is pretty easy and cost effective in various conditions and its flexibility allows to implement it in almost every foundry or metallurgical plant. Research limitations/implications: Further experiments should be carried out to solve some additional problems appearing during powder injection processes to make them more efficient in various technological conditions. Practical implications: Nowadays in Poland operate more than ten industrial stands for powdered carburizers injection, installation of furnace dust injection back to the melting furnace or pneumatic inoculation of alloys (mostly in cast iron foundries). Originality/value: The paper presents a few modern solutions for recycling and utilization of furnace dusts (in cupolas and EAF’s) and pneumatic carburization with use of powdered carburizers which are very often in form of grinded graphite electrodes wastes. All of the mentioned results and method had been developed in Department of Foundry and some of the designs had been previously patented.