Improvement of primary crushing technology for Stoilensky ferruginous quartzite using updated gyratory crushers manufactured KKD-1500/180

Abstract

Primary crushing is one of the critical stages in mineral processing, which governs efficiency and capacity of the follow-on ore pretreatment. Given the present-day activity of Stoilensky GOK toward an increase in production capacity and efficiency, improvement of primary crushing is the first-order condition of the strategic mission accomplishment. This article describes the primary crushing productivity enhancement project at Stoilensky GOK through retrofitting of primary gyratory crushers manufactured at Uralmashplant, which has ensured the annual production output of 38 Mt/yr. The main engineering solutions on redesign of crushers KKD-1500/180, aimed at enhanced capacity and optimization of end product size in the conditions of coarse grinding shopfloor at Stoilensky GOK, consist in optimization of ore feed, intensification of crushing effect and primary breaking in the upper zone of crusher chamber, as well as in improvement of functioning of heavy-duty friction assemblies of crushers. The in-proof test conditions, methods and results obtained after modernization of crushers KKD-1500/180 are presented. The implementation of modernization solutions ensured the hourly efficiency increase from 400 to 5563 t/h at the product outlet width of 180 mm. The grain size composition evaluation proved the product quality improvement connected with stable size and reduction of medium size of the crushed product to d05 = 232.65 mm. As a consequence, it is possible to enhance capacities in the next following stages of medium and fine grinding due to better ore pretreatment quality.