METHOD AND APPARATUS FOR CONTINUOUS MIXING AND FEEDING

PURPOSE:To mix continuously raw materials, namely, terephthalic acid and ethylene glycol always at a const. mixing ratio, to feed them to a reactor and to obtain continuously a polymeric substance with little ununiformity by mixing said raw materials by a specified method and feeding them to the reactor. CONSTITUTION:In an apparatus wherein terephthalic acid and ethylene glycol are mixed together by using pref. a slurry preparation tank 3 and fed into a reactor, a hopper 1 for feeding terephthalic acid is connected to the tank 3 through a rotary valve 2 and the amt. of feeding of terephthalic acid is controlled by controlling the number of rotations of the rotary valve while the flow rate of ethylene glycol is controlled by providing a flow rate controlling mechanism in a feed pipe 8 in such a way that a const. mixing ratio is obtd. to said amt. of feeding. Feed-back control of said two or raw materials is thereby performed in such a way that the amt. of feeding thereof is at a preset mixing ratio and the condition of mixing said raw materials is monitored by setting e.g. an electric conductivity meter 10 in the tank 3 to mix continuously said raw materials and to feed them to the reactor.