1 reply to this topic

[rahul22yadav]

Hi,
Can anybody help me on how to estimate the temperature of mixed stream when there are two temperature streams mixing together; also in addition to that how to estimate the mixture heat capacity.

Thanks in advance,

RY

[ankur2061]

rahul,

What you are asking is elementary heat balance which is normally taught in 2nd year of chemical engineering.

Basis: Two Streams Mixing (Stream 1 & 2) and forming Mixed Stream 3

Mass flow rate of Stream 1: M1 kg/h
Enthalpy of Stream 1: H1 kJ/kg
Mass flow rate of Stream 2: M2 kg/h
Enthalpy of Stream 2: H2 kJ/kg
Mass flow rate of Stream 3: M3 kg/h
Enthalpy of Stream 3: H3 kJ/kg

Mass Balance:

M1 + M2 = M3 ...........................(1)

Heat Balance:

M1*H1 + M2*H2 = M3*H3 ...........(2)

Now solve the above two equations to obtain M3 & H3

To solve (1) & (2) you obviously need to know M1, M2, H1 & H2.

Once you know H3 for the mixed stream, the corresponding temperature can be read of a Mollier chart for the mixed stream.

Looks like I am back in my 2nd year of chemical engineering undergraduate course.

Regards,
Ankur.

Edited by ankur2061, 18 July 2012 - 03:28 AM.