| Micro fine mineral particles(-20 μm) is high in titanium separation flowsheet, because titanium dissemination size is finer in ilmenite ore, and is limited by technological process of iron separation firstly and titanium separation secondly. It is difficult to recycle by convention flotation, causing huge drain of resources. For the above reasons, the conception about interface control to strengthen the ilmenite recycling by floc flotation was raised in the paper. Ilmenite and titanaugite were selected as research object, to realize the use efficiency of ilmenite by physical properties of cognitive, interface control, flocculation behaviour.Mineral characteristics and surface wettability were done in the paper firstly, and the research idea and objectives in which improved ilmenite separation by interface control and floc flotation intensified was made. Main research results include: the practicability of flocculation behavior and characteristic analysis of minerals were revealed; synchro-suppression and improved-dispersion and activation of regulators for minerals was put forward by titanaugite enter into froth product; the dispersion/aggregation behavior between particles were analyzed by interface controlled; adsorption- flocculation control behavior of sodium oleate onto minerals were analyzed, finally floc flotation of practical mineral was investigated.Mineral composition, embedded characters, surface wettability, surface free energy and solid-liquid interface interaction of ilmenite and titanaugite were studied. Researches show that element distributions of ilmenite and titanaugite have high similarity. Lamellar eutectic is mainly existed in ilmenite of aparsely disseminated, and microscopic wafer and wormlike is mainly existed in ilmenite of medium disseminated. Titanaugite is easy broken, and is disadvantage of flotation with slime. Wettability difference between ilmenite(-20 μm) and titanaugite is smaller and titanaugite is easy entry into concentrate. The thickness of hydrated film from titanaugite in aqueous medium is greater than ilmenite.Floc floatation behavior of ilmenite and titanaugite were studied. Hydrophobicity of particle was enhanced in optimal strong stirring, and effective collision was increased between flocs or flocs and particles. However, flocs were scattered broken again in exorbitant stirring intensity because of collision and heavily stressed. Flocculation characteristics of minerals were investigated by particle size analyses, morphological structure, floc fractal dimension, floc strength factor, regrowth factor, and turbidimetric tests. Mechanism for titanaugite enter into froth product was confirmed by interaction energy calculated between ilmenite and titanaugite. Primary approach in which titanaugite enter into froth product is true flotation and foam entrainment, not slime coating.Floc floatation, surface hydrophilicity, surface potential, disperse behavior, excitation behavior were studied to reveal synchro-suppression and improved-dispersion of regulators for minerals, to rearch effective separation for ilmenite and titanaugite. The results show surface properties of minerals were significant changed by CMC, sodium hexametaphosphate, acidize sodium silicate and sodium silicate. Sodium silicate was suitable inhibitor and dispersing agent and Pb2+ was suitable activator when ilmenite separated.By the AFM measurement and DLVO 、 EDLVO theoretical calculation, interaction force behavior was ascertained for particles in aqueous medium or sodium oleate solution. The results show interaction force focuses on attraction force between ilmenite praticles in aqueous medium, while repulsive force mainly excited for titanaugite praticles. In sodium oleate solution, inter-particle force focuses on hydrophobic force, and attraction force between titanaugite praticles is less than ilmenite/titanaugite particles, which is harmful to flotation.Adsorption- flocculation control analysis of sodium oleate onto minerals was studied. Adsorption isotherm, adsorption thermodynamics of sodium oleate adsorbed onto minerals was investigated. Adsorption flocculation mechanism was analyzed. The results show Langmuir model is more suitable for sodium oleate adsorbed onto minerals. Electrostatic adsorption, speciality adsorption, chemisorption and lyophobic adsorption were existed for sodium oleate adsorbed onto ilmenite. Flotation solution chemistry of ilmenite and sodium oleate was analyzed. Floc fractal dimension of minerals with different sodium oleate dosages was studied. While the sodium oleate dosage is 35 mg/L, floc fractal dimension of ilmenite and titanaugite is 2.96 and 2.15, respectively. Adsorption behavior and adsorption thermodynamics of sodium oleate adsorbed onto Ti4+、Fe2+ points was measured intuitively by QCM-D. Positioning ion was confirmed while sodium oleate adsorbed onto ilmenite.By strong string and static flotation column floc floatation, the 45.72% concentrate grade and 51.18% recovery is obtained using a rougher-a scavenger-three cleaner closed-circuit floc flotation flowsheet; the 47.21% concentrate grade, 55.31% recovery is obtained during magnetic separation- a rougher-a scavenger-two cleaner closed-circuit floc flotation flowsheet. Technological process was provided to recover ilmenite particles. |
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