Question

How to determine a CSTR working Volume

Answer 1

CSTR is a continuous stirred tank reactor.

Assumption in CSTR is that outlet concentration of species is same as bulk concentration of species inside the CSTR.

This assumption is thought to be valid because it is assumed that mixture will be continuously stirred in the reactor.

Now: lets assume component A is entering into reactor at flow rate of Fa and it is reacting at a rate of -rA. please note rA has unit of mol/liter/second

lets assume conversion of component A is X

Lets assume CSTR volume is V

Applying: Mole balance:

Accumulation rate of A inside CSTR = Inlet flow of A - outlet flow of A - A lost due to reaction.

Accumulation rate of A inside CSTR = Fa - Fa (1-X) -r_AV

at steady state Accumulation rate of A inside CSTR = 0

so Fa - F (1a-X) -r_AV = 0

so V = FaX/r_A