Sodium sulfate double-effect evaporator

A sodium sulfate double-effect evaporator is a rapid evaporation and concentration device, mainly used to treat solutions containing sodium sulfate to achieve sodium sulfate crystallization and recovery. The following is a detailed introduction to the sodium sulfate double-effect evaporator:

1. Sodium Sulfate Double-Effect Evaporator Process Flow

Pretreatment: The sodium sulfate-containing solution first undergoes pretreatment to remove solid impurities and suspended solids.

First-Effect Evaporation: The pretreated solution enters the first-effect evaporator, where it begins to evaporate and concentrate under the action of heating steam.

Second-Effect Evaporation: The secondary steam generated in the first-effect evaporator serves as the heat source for the second-effect evaporator, continuing the evaporation and concentration of the solution.

Crystallization Separation: The concentrated solution after the second-effect evaporation enters the crystallizer, where sodium sulfate crystallizes and precipitates out by controlling temperature and pressure.

Centrifugal Separation: The crystallized sodium sulfate is separated by centrifugation to obtain dry sodium sulfate crystals.

2. Technical Parameters of Sodium Sulfate Double-Effect Evaporator

Processing Capacity: Different processing capacities can be designed according to specific needs. For example, the processing capacity can reach 5T/H. 2.2 Evaporation Temperature: The evaporation temperature for a single effect is typically 80-90℃, while the temperature for a second effect is slightly lower.

Vacuum Degree: Depending on the specific process design, it is usually between 0.02 and 0.06 MPa.

Crystallization Purity: After crystallization through double-effect evaporation, the purity of sodium sulfate can reach over 97.5%.

3. Advantages of Sodium Sulfate Double-Effect Evaporators

Energy Saving: Double-effect evaporators significantly reduce energy consumption through the reuse of secondary steam.

Rapid Processing: High processing capacity, suitable for high-concentration sodium sulfate solutions.

Stable Operation: Stable system operation and simple operation.

Resource Recovery: Enables rapid recovery of sodium sulfate, reducing resource waste.

4. Application Cases of Sodium Sulfate Double-Effect Evaporators: 

In some industrial projects, double-effect evaporators are used to treat wastewater containing sodium sulfate, achieving rapid recovery and resource utilization of sodium sulfate. For example, in one project, a double-effect evaporator was used to treat wastewater containing sodium sulfate. The resulting sodium sulfate achieved a purity meeting industrial standards and could be sold directly or used in glass manufacturing.

5. Material Selection for Sodium Sulfate Double-Effect Evaporators

When selecting equipment materials, factors such as the corrosiveness of the solution, temperature, concentration, and economic efficiency must be comprehensively considered. 316L stainless steel is suitable for neutral or weakly acidic sodium sulfate conditions. Materials in contact with the material can be duplex stainless steel 2205 or stainless steel 316L.

Double-effect evaporators for sodium sulfate are widely used in sodium sulfate production and the treatment of sodium sulfate-containing wastewater due to their energy-saving, rapid, and stable characteristics. They not only improve resource recovery rates but also reduce production costs.