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[knapee]

Dear members:

I would like to ask for your help for the following question:
(PFD attached in the post)
Q1:

1" steam pipe header. OP=3kg/cm2g,OT=135C and after PCV pressure reducing valve (set pressure = 0.7kg/cm2g).

Refer to the Line sizing criteria, as steam header OP=3kg/cm2g(0.396Mpa), the velocity should be 15~20m/s,
and pressure drop =15Kpa/100m(0.15bar/100m) to meet the criteria.


Therefore, I uesd the line sizing spreetsheet to find out the steam flow rate = 70kg/hr barely meet this criteria,
but after the PCV set pressure=0.7kg/cm2g, the steam flow rate has to be decrease to 15kg/hr to meet the line size criteria.
But, I wonder why the mass is not balance; (70kg/hr or 15kg/hr can be use as the feeding flow rate to the reactor).

Q2:
Is the 1" steam pipe to be enlarge to 2" to reduce the line loss, although the the steam line to the reactor is around 10m
(Very short)?



Q3
The dew point for the mixed stream (toluene, N2, O2,and steam) is 38C. After it passes two condenser, the first condenser is cooling by cooling water (from 40C-> to 30C), , and the second condenser is cooling by chilling water (from 15C to 10C), I cound't find any condensate in HTRI report.
But, the dew point 38 C is higher than the outlet temperature of the two condensers, so it should be condensate forming after these two condenser.


Could any pro kindly help me out?

Thank you so much.

Attached Files

•  polyester acrylate.txt   2.75KB   5 downloads
•  dew point.png   19.54KB   12 downloads
•  line size criteria.png   33.56KB   16 downloads
•  steam p drop.png   10.71KB   8 downloads
•  Steam_Linesizing_Rev_1.xls   603KB   33 downloads