A

pre-exponential factor

c _A

concentration of component A

c _A,0

initial concentration of component A

C

carbon content (maf basis)

E

activation energy for reaction

g

Acceleration due to gravity

k _f

rate constant ( f = forward, r = reverse)

k _m

mass related rate constant

K _{p, T}

equilibrium constant of a reaction at temperature T

N

number of reaction stages

p

total pressure

p _A

partial pressure of component A

r _f

reaction rate ( f = forward, r = reverse)

r _m

mass related reaction rate

R

universal gas constant

t

time

T

temperature

^s v _A

volume fraction of component A in stream s

?

porosity

?

dynamic viscosity

?

kinematic viscosity

?

density

?

residence time