Posted by Tarzan on June 29, 2001 at 08:46:05:
In Reply to: flashing of condensate return through the vent of condensate return tank. posted by zaib on June 28, 2001 at 03:03:01:
: we have a 5 ton/h steam capacity 25 kg/sq.cm.pressure water tube boiler. the steam from boiler goes to plant(our is a BOOP poly films plant) here it passes through coils heats up the plant & return to condensate tank(our is gravity return system).capacity of condensate return tank is about 4 tons, it is vertical shell type. It has a three inch vent pipe at top of shell.we mix zeolite softener treated water as make-up in this tank which is of about 20 centigrade.now this mixture of (condensate return & soft water)we call it boiler feed water is forwarded to overhead feed water tank by means of a pump and from here it is again feed to boiler by means of boiler feed water pump.the problem is that there is a heavy flashing of condensate return through the 3 inch vent pipe of condensate return tank which I think is causing many tons of condensate to evaporate & is causing a big loss of condensate.moreover if we reduce vent pipe dia it will cause increase in pressure in condensate tank which may effect the return of condensate & also it will cause increase in water temprature which our pumps may not be able to forward(the pumps are ksb single impeller centrifugal).to forward very hot water above 100 centigrade what kind of pumps we should use who may forward the water of more than 100 centigrade.
: I request the members of this forum that kindly they give me there precious suggestions to resolve this problem.
: thanks & regard zaib.
Zaib,check your steam traps....Disconnect union down stream of trap and see if is passing raw steam into consensate return...
Check the temps of the return condensate at location near tank...if you don't have a thermometer installed on return condensate line, install a good one...Monitor it to help detect leaking traps and to gage progress of your repairs to them
....monitor make up water meter too...
You are correct that excess flash steam in condensate is wasteful and should be corrected.
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