Device and method for sub-boiling distillate membrane

The invention relates to the technical field of distillation, and discloses a device and a method for producing a sub-boiling distillate membrane. The invention discloses a device of a sub-boiling distillate membrane. A heating unit heats a chemical agent in a sub-boiling form to form micro-evaporation; the liquid film is heated and evaporated; the condensing unit is used for condensing the boil-off gas. The method comprises the following steps: heating a chemical preparation in a sub-boiling form to form micro-evaporation, and transmitting generated evaporated gas through a gas pump to pass through the chemical preparation to be purified and generate bubbles on the liquid level; heating a liquid film on the surface of the bubble, evaporating and condensing. According to the technical scheme, the heating temperature on the liquid level of the chemical preparation is utilized, the liquid film for evaporating bubbles on the liquid level of the chemical preparation is subjected to gas-liquid equilibrium sub-boil