Isolation of liquid urea from the off-gas of the synthesis of melamine
    1.
    发明授权
    Isolation of liquid urea from the off-gas of the synthesis of melamine 失效
    从三聚氰胺合成废气中分离出液态尿素

    公开(公告)号:US4616094A

    公开(公告)日:1986-10-07

    申请号:US568500

    申请日:1984-01-05

    摘要: A process for isolating liquid urea and its thermal decomposition products from the off-gas of melamine synthesis, which gas has been freed from melamine by fractional condensation and then been washed with molten urea, wherein the off-gas, containing 2-10 kg of melt per kg of pure gas, is passed at 8-30 m/sec tangentially into the upper part of an axially symmetrical separation zone. As a result of the rotation imparted to the gas/liquid mixture, the two phases are separated from one another, and both pass downward through the separation zone. The gas and liquid are separately taken off at the bottom end of the separation zone. The residence time of the gas mixture in the separation zone is not less than 0.5 second.

    摘要翻译: 从三聚氰胺合成废气中分离液态尿素及其热分解产物的方法,该气体已经通过分级冷凝从三聚氰胺中脱除,然后用熔融的尿素洗涤,其中含有2-10kg 每千克纯净气体的熔体以8-30米/秒的切向通入轴向对称分离区的上部。 作为赋予气/液混合物的旋转的结果,两相彼此分离,两者都向下通过分离区。 气体和液体在分离区的底端分开脱落。 气体混合物在分离区中的停留时间不小于0.5秒。