(under the class definition) Processes of purifying water in which the only material recovered as a product is water.
SEE OR SEARCH CLASS
159, Concentrating Evaporators,
5+, for concentrating apparatus of the film type, subclasses 13+ for evaporating apparatus designed to maintain the liquid being evaporated in a film and subclass 49 for an evaporating
process in which the liquid to be concentrated is spread in a thin film.
165, Heat Exchange,
3, for a process of adding water vapor to air or removing water vapor from air. 202, Distillation: Apparatus,
167, for a separatory distillation apparatus which includes a still and a feed water heater.
210, Liquid Purification or Separation,
600+, for a process of purifying a liquid not otherwise provided for.
423, Chemistry of Inorganic Compounds,
580.1, for processes of producing water and 580.2 for processes of producing heavy water including a chemical reaction.
