The application of sodium metabisulfite in mineral processing has multiple specific scenarios, mainly involving the use of it as a depressant to control the flotation behavior of minerals, thereby achieving effective separation of minerals.

For precious metal ores, gold and silver ores are mostly associated ores, associated with copper, mercury and other metal ores.

I. Technical specifications:

Inspection standard: GB1886.7-2015

Color: white or slightly yellow

State: crystalline powder

Sodium metabisulfite (as Na2S205): ≧96.5%

Iron (Fe) ≦0.003%

Arsenic (As): ≦1.0mg/kg

Heavy metal content (as Pb): ≦5.0mg/kg

II. Depressants in flotation process

Inhibition of sphalerite and pyrite:

Sodium metabisulfite can replace sulfite to inhibit sphalerite (ZnS) and pyrite (FeS₂). These minerals are often difficult to separate during the flotation process. By adding sodium metabisulfite, their floatability can be reduced, making it easier for other useful minerals to be separated.

Especially in the selection process of complex ores, the inhibitory effect of sodium metabisulfite is particularly important, which helps to achieve the fine separation of minerals.

Used in combination with other reagents:

Sodium metabisulfite is often used in combination with zinc sulfate, ferrous sulfate, ferric sulfate and other reagents to form a composite inhibitor. These composite inhibitors can more effectively inhibit minerals such as sphalerite and pyrite under weakly acidic pulp conditions (such as pH=5-7).

The inhibited minerals such as sphalerite can also be activated by adding a small amount of copper sulfate so that they can be recovered in the subsequent flotation process.

III. Adapting to the needs of complex ore selection

Combined use of reagents:

With the increase in the complexity of the ore, a single reagent is often difficult to meet the requirements of mineral processing. The combined use of sodium metabisulfite and other reagents has become an effective solution. By optimizing the reagent ratio and flotation conditions, the effective separation of multiple minerals in complex ores can be achieved.

Improve the efficiency and precision of mineral processing:

The addition of sodium metabisulfite helps to improve the surface properties of minerals during flotation, making it easier for mineral particles to be carried away by foam or remain in the slurry. This can not only improve the efficiency of mineral processing, but also reduce the energy consumption and cost of mineral processing.

VI. Environmental protection and safety considerations

Reduce environmental pollution:

As an inorganic compound, sodium metabisulfite is used in a relatively small amount in the mineral processing process and is easy to control. Through reasonable wastewater treatment measures, the pollution of sodium metabisulfite to the environment can be reduced.

V. Safety protection measures:

Although sodium metabisulfite is relatively safe in the mineral processing process, corresponding safety protection measures are still required. Operators should wear protective equipment such as protective glasses, masks and gloves to avoid direct contact with sodium metabisulfite or its solution. At the same time, the mineral processing workshop should be well ventilated to reduce the accumulation of harmful gases.

In summary, the application scenarios of sodium metabisulfite in mineral processing are wide and important. When used as a depressant, it can effectively control the flotation behavior of minerals; when used in combination with other agents, it can achieve effective separation of multiple minerals in complex ores; at the same time, through reasonable usage and wastewater treatment measures, it can also reduce pollution to the environment and ensure the safety of operators