| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a device for producing a polyisocyanate while capable of producing chlorine stably from a by-product, hydrogen chloride, capable of reacting carbonyl chloride with a polyamine stably, and also treating the by-product, hydrogen chloride efficiently. <P>SOLUTION: This device for producing the polyisocyanate is provided with that a hydrogen chloride gas-controlling part 32 controls a flow-controlling valve 23 to make the feeding amount of the hydrogen chloride fed to a hydrogen chloride-oxidizing vessel 6 from a hydrogen chloride-purifying column 4 through a second hydrogen chloride gas-connecting line 11 as a constant, also the hydrogen chloride gas-controlling part 32 controls a pressure-controlling valve 22 based on the pressure at the inside of the hydrogen chloride-purifying column 4, input from a pressure sensor 25, to discharge the hydrogen chloride gas to a hydrogen chloride-absorbing column 5 from the hydrogen chloride-purifying column 4 through a first hydrogen chloride gas-connecting line 10 so as to make the pressure in the hydrogen chloride-purifying column 4 as a constant. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
