Effects of LPD mixer and Kenics mixer inserted in a tubular reactor on the residence time distribution, pressure drop and conversion were investigated. Reactors of two geometries were used for the experimental work, namely one 25mm in diameter and 1meter in height and the other 13.5mm in diameter and 45cm in hight. Nine pairs of Kenics mixers were inserted in each of the reactors. The saponification reaction of ethyl acetate, an irreversible second order reaction, was adopted for the reaction runs. The reactor model was determined from the residence time distribution obtained from tracer experiments.
The values of the conversions at different operating conditions and reactor geometries were predicted by the model chosen from the tracer studies and compared with the experimental data.
It was found that the reactor could be simulated with a nine equally sized CSTR'S in series models.
For empty tubes, the deviation in conversion from a PFR increased with the increase in the reactor diameter for the same residence time, whereas inserting static mixers in the tube the discrepancy of conversion from a PFR was found to be 7% regardless o the magnitude of the reactor diameters. LPD mixer increased friction factor of the empty tube by a factor 20 to 25. The friction factor vs. Reynolds number plot showed that the LPD mixer made the flow turbulent.
관형 반응기내에 Kenics mixer과 LPD mixer를 장치할 때 체류시간 분포, 압력 강하 및 전화율에 미치는 영향을 고찰하였다.
실험에 사용한 반응기 크기는 직경25mm 높이 1mm인 것과 직경 13.5mm 높이 45mm인 것 두가지이며 9쌍의 Kenics mixer와 LPD mixer를 장치했다. 반응으로는 EtOAc의 2차 비가역 비누화 반응을 채택하였다.
먼저 추적자 실험으로 체류시간 분포를 구하여 dispersion number와 반응기 모형을 구하고 이를 사용하여 전화율을 예측하고 실험치와 비교 검토하였다. 그 결과 9쌍의 Kenics mixer를 장치한 반응기는 9-CSTR in series model로 전화율을 예측할 수 있었다.
Static mixer를 사용하면 PFR에서 벗어나는 정도가 7%, static mixer을 사용하지 않으면 12%로 나타났었다. 압력 강하는 LPD mixer를 사용하면 empty tube보다 friction factor가 20-25배 증가하였다.
