Abstract: An evaporator or distillation apparatus includes an inlet supply line for supplying an influent liquid, a heater configured to heat the influent liquid supplied by the inlet supply line, and a plurality of cells. Each cell includes an outer surface defining an interior chamber, an inlet, a vapor outlet, a concentrate outlet, and an inner conduit in fluid communication with the inlet. At least a portion of the inner conduit is positioned within the interior chamber. The vapor outlets of the plurality of cells are connected to each other in a parallel configuration and the inlet supply line is connected to the inlet of each cell.