Technological Simulation Regarding the Joint Leaching of Oily Rolling Scale and Red Mud

Based on the data analysis on beneficial use of red mud and oily rolling-mill scale, a novel direction of utilization has been formulated consisting in the joint processing of these wastes with liquid products. The technological simulation covering the joint water treatment stage of a red mud and oily rolling scale mixture has been performed using an enlarged setup. The yields and compositions of the products have been determined. A batch of washed precipitate has been sent for the studies on obtaining iron-containing raw materials for the subsequent pyrometallurgical processing. At a ratio between the component amounting to 1 : 1, at a solid-to-liquid ratio of 4, and at a temperature of 95°C and duration amounting to 2 h, 6.3 kg of the mixture have been processed. Resulting from this procedure, 6.58 kg of washed precipitate with a moisture content of 21.3% and 12.6 dm3 in volume of the final solution have been obtained. The specific volume rate of water evaporation has been determined to amount to 31.3 dm3 /h per 1 m2 of pulp surface. Based on the iron concentration in the precipitate (54.4%) and in the final solution (1.1–1.3 mg/dm3), it is shown that iron is almost completely accumulated in the precipitate. Silicon, aluminum, phosphorus, sulfur, sodium oxide and organic matter impurity concentration in the processing products have been determined. According to the results, the joint processing flowsheet of red mud and oily rolling-mill scale has been developed and the ways for using the processing products have been outlined: supplying the precipitate for obtaining iron, supplying the filtrate to industrial purification, as well as supplying evaporated and flushing water to leaching. Using the cooperation between enterprises of the Kamensk-Uralskii Industrial Complex as an example, a schematic diagram of equipment intended for processing is considered. It is worthwhile to use the obtained data in order to implement the technology, in particular, for the development of technological regulations for the design of a pilot plant.