summaryseven

## Homework Statement

At steady state, a stream of liquid water at 20C, 1bar is mixed with a stream of ethylene glycol (M=62.07 g/mol) to form a refrigerant mixture that is 50% glycol by mass. The water molar flow rate is 4.2 kmol/min. The density of ethylene glycol is 1.115 times that of water.

Determine

a) the molar flow rate, in kmol/min, and volumetric flow rate, in m3/min, of the entering
ethylene glycol.

## Homework Equations

m1 + m2 = m3

m1h1 + m2h2 = m3h3

## The Attempt at a Solution

Firstly, I do not know whether is there a leaving flow on the ethylene glycol there that make it to have the m3 flow rate to exist.

If I assume there is a flow rate exit there,

Vf = 0.001002 m^3/kg
Density of water = 1/0.001002
= 998 kg/m^3
Density of ethylene = 1.115 x 998
= 1112.77kg/m^3

Mw = 18.015 kg/kmol
Volume flow rate of water = 18.015(4.2)(0.001002)
= 0.07581 m^3/min

0.07581 + m2 = m3

If I assume that the mass flow rate for the exit one is m3 = 0.5m2

The answer turns out to be negative, which i dont think is correct