Nghiên cứu công nghệ tuyển nổi quặng apatit loại III tại khai trường 27, 28, 29 xã Bát Xát, tỉnh Lào Cai

Abstract

This study focuses on the flotation technology of Type III apatite ores from mining sites 27, 28, and 29 in the Ban Vuoc – Ban Qua area, Bat Xat district, Lao Cai province, Vietnam. These ores are characterized by low P₂O₅ contents (12–16%) and high proportions of silicate, carbonate, and clay minerals, which pose challenges for beneficiation and limit industrial applications. Two representative samples (M1 and M2) were analyzed using XRD, polarizing microscopy, AAS, ICP-OES, and particle size distribution. Results indicated that most P₂O₅ is concentrated in the fine fraction (<0.045 mm), highlighting the need for fine grinding to liberate apatite minerals. Flotation tests were carried out to determine the optimal flowsheet and processing parameters. The proposed scheme consists of one rougher flotation, three cleaners, and one scavenger. Optimal conditions were: grinding fineness of 85–90% <0.074 mm, pulp density of 25% solids, pH = 9, fatty acid collector dosage of 500 g/t (MD/VH = 150/350 g/t), and sodium silicate dosage of 500 g/t. Under these conditions, the concentrate achieved P₂O₅ grades of >32% with recoveries of 83–85%. Compared with previous studies in Cam Duong and Tang Loong, where recoveries typically reached only 70–75%, these results represent a notable improvement and are comparable to some international flotation technologies. A key advantage is the reliance on locally available equipment and reagents, ensuring feasibility and reducing dependence on imports. This research provides new scientific data on Type III apatite ores from a previously unreported area and demonstrates practical significance in improving low-grade ore utilization, reducing pressure on high-grade deposits, and ensuring a stable domestic supply of raw materials for fertilizer production.