Route to simulate a circulated leaching column

MFiX
#1

Hi,
I am going to simulate a leaching system where the solutions will be collected and reinject to the system.
The solutions keep passing the particle bed in a column with species exchange between the fluid and solid phase. The outlet fluid will be collected to reject into the column.
Since the species concentration changes each time, I need to continuously change the fluid inlet property and mock them to the fluid outlet surface.

Any suggestions to simulate this process in the MFIX platform.

#2

I can set the Y dircetion as the cyclic. However, this operation also let the particles cirulate the domain, which is not satisfied with real operation.
I also noted that by setting the bc_po/mi_ to_des as flase the solid phase can be detained in the domain.
The problem is that i can not build the po or mi plane in the Y direction.