Strengthening Low‐Basicity Sintering Process Based on Granulation and Composition Optimization

Low‐basicity sintering serves as a reserve process route designed for inferior iron ore feedstocks and complex operational conditions, yet it faces challenges, including deteriorated sintering production‐quality indexes and fluctuating sinter performance. This study proposes an integrated enhancement approach for low‐basicity sintering through granulation and composition optimization. At the granulation level, the developed composite agglomeration technology, which enhances the physical bonding between high‐silica ore (demonstrating the strongest calcium ferrite formation capability) and lime, results in significant process improvements: the yield increases from 63.24% (baseline) to 65.33%, the tumbler index improves from 57.8% to 58.34%, the solid fuel consumption decreases from 57.82 kg t −1 to 55.72 kg t −1 , the productivity improves from 1.12 t·(m 2 ·h) −1 to 1.21 t·(m 2 ·h) −1 , while the sintering end‐point temperature is reduced from 496 °C to 463 °C. At the composition optimization level, with the simultaneous increase of SiO 2 and CaO contents (resulting in decreased basicity), the yield, tumbler index, and productivity exhibit a characteristic “U‐shaped” trend, initially decreasing before subsequently increasing. Specifically, optimal sintering performance is achieved at SiO 2 contents of 5.2–5.3% and 5.7–5.9%. Through the above two optimizations, the synchronous enhancement of both production‐quality indexes and energy efficiency in low‐basicity sinter production can be ultimately achieved.