Ethylene dryer bed chocking

[amar122amar]

We have an ethylene dryer bed to remove trace quantity (ppm level) of moisture before it is fed to the reaction system. There are ceramic (Alumina) support ball at bottom and top of the bed. Recently for bed replacement we have regenerated it with nitrogen to remove hydrocarbons and did steam deactivation before opening it. We have observed lump formation of ceramic balls at the bottom of the bed. What may be the reasons of chunk/lump formation of ceramic balls?

 

[Compositepro]

One guess is polymerization of ethylene on the surface of the Alumina.

 

[amar122amar]

Thanks for response Compositepro, What may be reasons for polymerization of ethylene on the surface of the Alumina?