In: Other
One good example of Energy balance equation is single effect evaporator.
The schematic of a single effect evaporator is shown in figure. In oredr to develop the governing equations of the system we aasume
i> steady state
ii> no heat loss in the surrounding
iii> no entrainment of the liquid droplets(y=0)
iv> only latent heat is transferred from the steam side
with the stated assumptions, the governing balance equations are
overall material balance : F = V +L
component balance (solute): FZF = Lx
energy balance equation: ........1>
where
subcooled heat load
Latent heat load
Total heat load = subcooled heat load + Latent heat load
Another energy equation can be written as
capacity equation : ........2>
1 and 2 equations are energy balance equation.
Parameter used here are:
F = feed flow rate
ZF= inlet feed composition
tF= inlet feed temperature
V= vapour to condenser
= steam flow rate
= latent heat of steam
L = liquid flow rate
x =lquid composition
Q = total heat
tSt = steam temperature
tF = feed temperature
ts = saturation temparature