Filtration Property of Pure Willemite Acid Leaching Sludge Under Pressure

The filtration problems on acid leaching sludge of high silicon zinc ore have been extensively studied in the context of zinc hydrometallurgy. This research aims to evaluate the effectiveness of converting soluble silica into silica precipitate with desirable settling and filtration properties. The methodology involved investigating the filtration rate, viscosity, and concentration of silica in the leaching sludge and liquor under controlled leaching conditions. Results indicated that the filtration rate could exceed 800 L/m²·h when optimal leaching conditions were applied. Additionally, it was found that increasing the filtering temperature significantly enhanced the filtration property of the pulp. The experimental data underscored the critical role of the viscosity of the leaching liquor as a determinant factor affecting the filtration properties of the sludge. This study highlights the importance of managing silica sol behavior in the leaching process to improve zinc recovery rates and facilitate subsequent purification and electrolysis treatments.