The thermal desalination process is based on the evaporation and subsequent condensation of steam. The following thermal desalination technologies from WABAG demonstrate special strengths:

• Multi Effect Distillation (MED)
• Thermal Vapour Compression (MED-TVC)
• Mechanical Vapour Compression (MED-MVC)
• Multi Stage Flash (MSF)

Salient Features of MSF Process:

• Repeated flash evaporation occurs in successive stages at lower pressures. (typically 15-30 stages) 
• The water vapor is condensed on outside tubes, cooled by seawater.
• Most MSF plants recycle the brine.
• Commonly used for dual-purpose plants (water & electricity).
• Commercially competitive for very large-sized plants.
• Matured and well developed process.
• Produces high quality water suitable for Industrial applications.

Salient Features of MED Process:

• Vapour generation is due to film boiling process 
• Repeated vapour generation in successive stages at lower pressures. (typically 6 – 8 stages) 
• Water vapor is condensed inside the tubes and cooled by seawater sprayed outside the tube.
• Taking over MSF process due to development and low capital cost associated with higher efficiency.
• Also being used for dual purpose plants (water & electricity).
• Commercially competitive for medium to large-sized thermal plants, especially when free steam is available)
• Produces high quality water suitable for Industrial applications.

Salient Features of MVC Process:

• Compact thermal desalination unit used in ships
• Desalination plants based on Mechanical Vapour Compression (MVC) technology are inherently the most thermodynamically efficient.
• Suitable for small capacity thermal plants
• Produces high quality water
• Does not require more steam compared to MSF and MED process.

Brochure “Thermal Desalination”