Atmospheric Flash Tank - Turbine

[novakoni]

Dear friends,

I have a little bit strange problem:

- I should design atmospheric flash tank - mainly for steam line drains and turbine main valve warming up.
- Flash tank should be placed in turbine building and collect all live steam line drains and warming up line. Practically it will be used only during start-up period.
- It is required in tender documentation that this flash tank should be atmospheric, there is no utilization of steam - it's directly vented to atmosphere.
- Requirement is also that we should try to reduce steam amount blowing to atmosphere - practically design should provide condensing of steam at some extension.
- Max temp. of outlet hot water should be approx. 65oC - meaning that cooling should be provided.
- Steam and overflow condensate are to be waste - steam to atmosphere, condensate to drain pit.

What complicate things for me is:
- even if there will be no utilization of heat or condensate - I have a task to reduce a flashing steam - by condensation.
- I have experience with submerged perforated pipes as drain inlets, cooling water injection directly to tank and overflow from the bottom of tank with water lock - but this system was not so effective - as hot condensate was leaving through overflow with flashing even with fully open cooling water supply.
- Especially warming-up line could have considerable flow - that will practically force hot condensate overflow with intensive flashing at overflow outlet.


Does anyone have experience with similar systems or requirements - and if you have any suggestions what could be the best system for this application?

thanks in advance

 

[steamdog]

We do two things:
Vent Condenser: basically some coils in the vent piping with cold water in them. You heat up the water and the steam in the vent condenses.

Or

Water in the tank: We use a self contained cooling water valve and a spray nozzle. We spray right into the vent using a spray valve. So that this cooling water condenses the steam.