In __________ reactor the bed is filled with a packing material that expands when wastewater moves upwards.

In __________ reactor the bed is filled with a packing material that

1.	In __________ reactor the bed is filled with a packing material that expands when wastewater moves upwards.
A.	Fluidized bed reactor
B.	Packed bed reactor
C.	Plug flow reactor
D.	Mix batch reactor
Answer» B. Packed bed reactor