Abstract: Method and plant for fluid purification by distillation comprising a reservoir (1) with a fluid containing diluted solids provided with an impurities filter on its outlet (2); a pump (3) connected to the reservoir outlet (1) and set up to increase the fluid containing solids pressure and temperature; and a heat area (4) for the fluid containing solids comprising a plurality of ducts contacting with a heat transfer fluid; and, furthermore, comprising a convergent-divergent nozzle (5) connected to the heat area outlet (4) and set to increase the biphasic liquid-vapor fluid speed so the diluted solids contained in the fluid already heated settle in a solids reservoir (6), whereas the fluid passes to a condenser (7) and then to a purified fluid reservoir (8) already in liquid state.