(88a) Pressure Distribution in a Three Phase Moving Bed

Heterogeneous reactions widely exist in chemical industries. Dispersed principles of different heterogeneous reactions result in the developments of various multi-flow reactors, e.g., the fluidized bed for polymerization, the trickle bed for hydrocracking of cat-cracked gasoil and vacuum gasoil. Therefore, confronting so many kinds of heterogeneous reactions, and constantly demands of increasing the product qualities and decreasing the process energy consumption, developing new multi-flow reactors is always necessary and significant. This work aims at developing a totally new gas-liquid-solids three phase moving bed reactor on the basis of gas-solid moving bed and trickle bed. The advantages of the three phase moving bed reactor may include: 1) gas, liquid and solid phase are close to the plug flow; 2) the residence time of catalyst particles is easy to control, and the regeneration operation of catalyst is convenient; 3) the cold gas quench can be designed between different stages of the reactor to easily control the reactor temperature increase, and the separation of liquid products can also be applied between different stages to easily control the reaction rate.

A cold-model experimental apparatus of the three-phase moving bed was established, which mainly consists of four parts: the inlet system, the reaction unit, the discharging and separation system, and the inner structures for even flow distribution. The pressure distribution in the moving bed reactor was investigated. The results showed that the pressure drop linearly increased with the length of the reactor in the situation without liquid, and the increasing rates were higher at larger gas velocities. Moving of solid particles further increased the pressure drop. As liquid was injected into the reactor, it made the further increase of pressure drop. The uneven distribution of liquid distorted the linearly distribution of pressure drop. The building up of cold-model experiments and the experimental results will provide guidance for the scale-up of three-phase moving bed reactors.