Patents Assigned to Toyo Enginnering Corporation
  • Process for concentrating aqueous urea solutions
    Patent number: 4316767
    Abstract: Disclosed is a process for concentrating aqueous urea solutions in which an aqueous urea solution is allowed to flow as a falling film in countercurrent contact with a stream of hot inert gas to concentrate it to 95-99% by weight and the aqueous urea solution so concentrated is then passed through a packed zone in cocurrent contact with a stream of hot inert gas to concentrate it to not less than 99.5% by weight.
    Type: Grant
    Filed: September 11, 1980
    Date of Patent: February 23, 1982
    Assignees: Toyo Enginnering Corporation, Mitsui Toatsu Chemicals Incorporated
    Inventors: Toyoyasu Saida, Takatatsu Shimokawa, Yuzuru Yanagisawa, Takashi Nagahama, Koji Ishida