Polyethylene Reactor Grid Design

Example 4 Design a flat, perforated-plate grid for the polyethylene reactor schematically shown in Fig. 11, and calculate the gas j et penetration depth. Use a triangular pitch. System parameters are  

Determine the gas velocity through the grid hole, (trial and error)-assume Cd = 0.8 

Gas jet penetration depth using Merry s correlation (Eq. 2) for horizontal jets  

The low value of X indicates that the bed of solids is probably suspended above the coalesced jets. Therefore, the solids rarely come into contact with the grid. This type of design reduces the chances of grid pluggage due to sticky polyethylene solids. 

---