The size of the inert ceramic ball should be selected according to the size of the catalyst. Generally, it follows the 2X rule (or gradation), that is, the diameter of the ceramic ball should be twice the diameter of its adjacent catalyst so that the distribution of materials is the most uniform and the pressure drop It is also the smallest and the reactor is optimized.
In a fixed-bed reactor, a certain height of inert ceramic balls or fillers is usually added above and below the catalyst.
The function of the upper ceramic ball is better understood and improves the feed distribution. What role does the lower ceramic ball play? Is it just catalyst support? Can it be done?
In addition, there are hard regulations for the filling height of the inert ceramic balls. What is the basis for this regulation height?
Usually, two layers are laid. The layer next to the catalyst is covered with 1~3mm porcelain balls, the outer layer is covered with 4~6mm porcelain balls, and the wire mesh is laid on the outermost layer. The wire mesh is mainly used for gas distribution, filtering small particles of catalyst entrained by gas or filtering impurities entering the bed. It also plays a role in preventing the falling of the bed and supporting the bed. Generally, each size of the ceramic ball is 100mm thick. Did not notice that there are regulations in that standard. Even very fine catalyst particles cannot be filtered by this method, and other methods need to be taken to filter the catalyst that may be carried out.
