不同温度下空气-聚醚多元醇的搅拌特性

在直径为0.28 m椭圆底搅拌釜内,以空气-聚醚多元醇为实验物系,对20～120℃范围内不同温度下两种三层组合桨的搅拌功率及气含率特性进行了实验研究,并获得了不同组合桨的相对功率消耗及气含率关联式。结果表明：随着通气流量和搅拌转速的增大,两种组合桨的气含率均升高,相对功率消耗均减少;随着温度的升高,两种组合桨的气含率和相对功率消耗均减小。但组合桨Ⅰ（底HEDT＋中WHu＋上WHu）的综合性能要优于组合桨Ⅱ（底6XYK＋中6XDT＋上HEDT）,有利于获得较高的气含率和通气搅拌功率,更适合用于聚合体系气-液两相混合操作过程中。

An experimental investigation on the air-polyether polyols stirring characteristics at different temperatures

Considering air-polyether polyols（PPG）as Gas-Liquid systems，the power consumption and gas holdup characteristics with two types of three-lay impellers were investigated in a stirred tank with elliptic bottom and internal diameter of 0.28 m at 20-120 ℃. The Relative Power Demand and gas holdup were correlationed for different multiple impellers. The results showed that gas holdup increases，while Relative Power Demand decreases along with the increase of gas flow rate and rotary speeds in the two impeller combination. As temperature increases，the two impeller combination gas holdup and Relative Power Demand reduce. However，multiple impellersⅠ（a half elliptical disk turbine，6-HEDT，at bottom and two up-pumping wide-blade hydrofoils ，WHu，above 6-HEDT）had better performance than multiple impellers Ⅱ（six inclined unseal turbine，6-XYK，at bottom，six inclined disk turbine，6-XDT，in middle and 6-HEDT at top）for its higher gas holdup and stirring power under the aerated condition and it was more suitable for the operation of gas-polyether polyols dispersion.