Mixing and heat integration of melt tray liquids in a cryogenic distillation tower

A cryogenic distillation tower for separating a feed stream, the distillation tower comprising:

• a distillation section permitting vapor to rise upwardly therefrom;
• one or more lines for directing the feed stream into the distillation tower;
• a controlled freeze zone section situated above the distillation section, the controlled freeze zone constructed and arranged to form a solid from the feed stream, the controlled freeze zone section including
• a spray assembly in an upper section of the controlled freeze zone, and
• a melt tray assembly in a lower section of the controlled freeze zone, wherein the melt tray assembly includes
• at least one vapor stream riser that directs the vapor from the distillation section into liquid retained by the melt tray assembly, and
• one or more draw-off openings positioned to permit a portion of the liquid retained by the melt tray assembly to exit the controlled freeze zone section;
• a heat exchanger arranged to heat the portion of the liquid through indirect heat exchange with a heating fluid;
• and
• one or more return inlets that return the portion of the liquid to the melt tray assembly after the portion of the liquid has been heated in the heat exchanger.