Tin Ore Beneficiation Processes and Equipment

I. Gravity Beneficiation Equipment for Tin Ore

Gravity separation equipment for tin ore typically includes shaking tables and jigs. Prior to gravity pre-concentration, ball mills and classifiers are required.

• Tin Ore Shaking Table: Primarily suitable for processing fine-grained tin ore. For tin ores with a low degree of liberation, simple gravity separation using a shaking table often fails to achieve ideal grade and recovery rates. A multi-stage grinding and multi-stage gravity separation process is necessary to improve recovery.

  

• Tin Ore Jig Machine: Suitable for separating coarse-grained mineral particles. In tin ore beneficiation, provided the specific gravity difference is ≥1.25 and the ore particles are liberated, the lower size limit can reach 0.04mm. Jigs perform very well in processing alluvial tin sand ores with a high degree of liberation.

  

• Tin Ore Ball Mill / Rod Mill: Includes three types: grate discharge ball mills, overflow ball mills, and wet rod mills.

• Grate Discharge Ball Mills: Used for coarse grinding in tin ore processing, typically in the primary grinding stage, often forming a grinding-classification circuit with spiral classifiers.

• Overflow Ball Mills: Mainly used for fine grinding in tin ore processing, generally in the secondary grinding stage, frequently forming a grinding-classification circuit with hydrocyclones.

• Rod Mills: Can be used for fine crushing and coarse grinding operations.

  

• Classifier: Includes hydrocyclones and spiral classifiers.

• Spiral Classifiers: Used for coarse particle classification.

• Hydrocyclones: Used for fine particle classification.

  

II. Flotation Beneficiation Process for Tin Ore
The flotation process is mainly used for treating fine-grained cassiterite. Due to the brittle nature of cassiterite, liberation and inherent fractures can lead to over-grinding and sliming during the milling process. Therefore, pre-treatment or selecting effective flotation reagents and equipment can help mitigate these issues.

Furthermore, flotation is conducted in a liquid medium, where certain ions can significantly impact the action of collectors. Particularly, the presence of some metal cations greatly affects cassiterite flotation, causing partial changes in their properties and forms on the mineral surface. Consequently, attention must be paid to the influence of ions during cassiterite flotation.

Cassiterite Ore Flotation Beneficiation Equipment
Flotation equipment for tin ore is primarily determined by the properties of the ore. The required equipment mainly includes pre-concentration devices, flotation machines, and flotation reagents.

• Tin Ore Pre-concentration Equipment: Common pre-treatment methods include intense agitation of the pulp, classification using large-diameter hydrocyclones, de-sliming using small-diameter hydrocyclones, and lowering the cut-off size for classification and de-sliming. The main equipment required includes agitation tanks and hydrocyclones.

• Tin Ore Flotation Equipment: Mainly comprises two types: mechanical agitation flotation machines and inflatable agitation flotation machines.

• Tin Ore Flotation Reagents: Common flotation reagents for tin ore are primarily collectors and modifiers.

• Activators (e.g., sulfuric acid, copper sulfate, sodium sulfate, hydrochloric acid, soda ash)

• Depressants (e.g., sodium silicate, lime, sodium hexametaphosphate)

• pH Modifiers (e.g., salicylhydroxamic acid, hydroxamic acid, P86, pine oil)

• Collectors: Include fatty acids, alkyl hydroxamic acids, phosphonic acids, alkyl sulfosuccinates, arsonic acids, etc.

  

III. Magnetic Separation Beneficiation Process for Tin Ore
Tin ores often contain associated minerals like iron oxides and tungsten minerals. Such ores cannot be directly separated using gravity or flotation methods alone. Therefore, magnetic separation is first employed to remove iron-bearing materials, after which other processes are used to complete the tin ore separation. Magnetic separation for tin ore includes wet high-intensity magnetic separation and dry magnetic separation.

• Wet High-Intensity Magnetic Separation: Used for iron removal from run-of-mine ore, middlings, and concentrates before they enter the gravity separation circuit.

• Dry Magnetic Separation: Used for separating tungsten-bearing minerals from tin ore.

Tin Ore Magnetic Separation Equipment
Magnetic separation equipment for tin ore mainly includes wet high-intensity magnetic separators and dry magnetic separators.

• Tin Ore Wet Magnetic Separator: Features a large wrap-angle magnetic system, which increases the length of the separation zone and the number of magnetic flips, enabling efficient separation of magnetic minerals from non-magnetic (or weakly magnetic) minerals.

• Tin Ore Dry Magnetic Separator: Since both tin and tungsten have high densities, dry magnetic separators can be used to separate coarse-grained wolframite/scheelite from cassiterite. Subsequently, electrostatic separation can be applied to separate cassiterite from scheelite.

  

Final Recommendation:
As each ore deposit is unique, it is recommended to conduct beneficiation tests prior to designing the processing plant.