PRESSURE DROP CHARACTERISTICS OF DISTRIBUTOR IN GAS-LIQUID CONCURRENT UP-FLOW REACTOR

Abstract

Abstract: The pressure drop characteristic of new and reference gas-liquid distributors and the effect of flow rates of gas and liquid on the pressure drop were studied in a cold gas-liquid concurrent up-flow reactor model device. The results showed that for both two type of distributors, the pressure drop increased first and then decreased with the increasing gas flow rate, while increased with liquid flow rate up. However, the pressure drop of new gas-liquid distributor was larger than that of the reference one under the same conditions. The relevant mathematical model was established to predict the pressure drops for two gas-liquid distributors, including bottom part inlet pressure drop, middle part rising tube pressure drop, and top outlet pressure drop. The model calculation and verification results showed that in reference gas-liquid distributor, the top part pressure drop dominated, while in the bottom part and middle part was less, where the gravity pressure drop accounted for the largest proportion in the middle pressure drop, and the acceleration pressure drop could be ignored. The trend of pressure drop calculated by the model was basically the same as that of the experimental value with the liquid flow rate, but the calculated value of pressure drop was larger than the experimental value under the same conditions, and the deviation between them gradually increased with the increase of liquid flow rate. The reason was that the flow pattern of gas-liquid two phases in the actual distributor will change, which leads to the deviation of the calculated value of the model becoming larger.

Key words: up-flow reactor, gas-liquid distributor, pressure drop, mathematic model

References

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