| 摘要 |
<p>1,247,377. Apparatus for preparing melamine. STAMICARBON N.V. 21 Nov., 1968 [21 Nov., 1967], No. 55384/68. Heading B1X. [Also in Division G3] An apparatus for preparing melamine from urea, comprising a reactor 1 fed through ring conduit 2 from lines 3, 4 and 5, a saturation cooler 7, a scrubber 8 and an absorber 9 fed by circulation conduit 6, is controlled by means of pneumatic pressure signals which are inversally proportional to pressure and flowrate, said signals being emitted by pressure-sensitive devices 18 and 21 which operate valves 12 and 15 respectively, a flow-rate-sensitive device 19 which operates valve 17, devices 18 and 19 being connected to a comparison element 20 which operates valve 16 in the vent line 11.</p> |
