Learn about Multi Stage Flashing (MSF) distillers.  They are the bulk producers.  They are thermal systems, which are associated with thermal power plants (usually steam operated).  both the units Power plant as well as the distiller will have to be placed closer to sea shore.  I have attached a PPT for your ready reference with MSF distillation.  

If you plan for smaller units, then, you can learn about the Reverse Osmosis (RO) distillers.  

At Saudi Arabia has the world's largest plants in MSF and RO distillers, at Al-Jubail and at Al-Kobar.  If times, try to visit those plants where you can learn a lot to construct and operate the plants.  

Membrane based desalination may be better option for this capacity desalination requirement. Understanding intake facility/point, appropriate pretreatment to handle seasonal variations and proper material selection (sea water is highly corrosive) are some of the very important aspects of constructing a membrane based desalination plant. membrane based RO are energy intensive and therefore energy recovery devises (hydro booster or work exchangers) are equally important.