| 摘要 |
PURPOSE:To realize the aimed-at mixing rate more rapidly than required by conventional natural emission of gas by a method wherein the emission of gas in liquid is accelerated by positively lowering the pressure in a liquid tank, when the mixing rate of gas in liquid becomes larger than the target value. CONSTITUTION:A passage is made by connecting a stock solution tank 1, in which liquid component of plastic is stored, through a selector valve 3, three-way valves 4 and 5 with a circulating cylinder 6. At the same time, a circulating passage, which returns through the three-way valves 4 and 5 and a piping 2 to the stock solution tank 1 again, is also made. An actuator 8 drives the piston 7 in the cylinder 6. A gas blowing-in device 10 is arranged in the piping 2. The mixing rate of gas in liquid is obtained based upon the signals sent from a pressure sensor 15 installed on the cylinder 6 and from an encoder 14, which reads the position of a piston 7a. When the obtained mixing rate is lower than the set value, a valve 23 is open to mix more gas in the liquid. When the mixing rate is higher than the set value, the gas in the liquid is emitted by means of the controlling mechanism 25 of the pressure in the tank 1. The liquid, the gas mixing rate of which is controlled as just mentioned above, is sent to a metering cylinder 30 and a head 31 in order to be subjected to the reaction. |
