Steam/condensate hammer at low steam load
Steam/condensate hammer at low steam load
(OP)
Hi everyone
I have a question regarding hammering that occurs at low steam flow rates. So some background
There are 6 distillation column reboilers that run on 250# steam controlled with a steam control valve. The condensate outlet of each of these reboilers go to float traps on each respective reboiler condensate outlet pipe. The discharge piping of each of these traps tie into a common header and then dump into a flash tank set at 50#. Here's the issue
At low steam flow rates - specifically when we shut down the distillation train to boil the columns out, we experience hammering in the condensate return header to the flash tank, eventually leading to gasket failures.
I have to note that the condensate return header does not have a dip pipe down into the liquid level of the flash tank. Also, 4 of the 6 reboiler traps do not have check valves downstream of them. As soon as a gasket fails, and we get a large condensate leak, the hammering subsides.
I have a few theories on why this occurs, but I wanted to hear others' input and experience with this type of issue. Also I would like to know if anyone can point me in the right direction as far as a redesign of the system or things we can do to mitigate the issue.
I have a question regarding hammering that occurs at low steam flow rates. So some background
There are 6 distillation column reboilers that run on 250# steam controlled with a steam control valve. The condensate outlet of each of these reboilers go to float traps on each respective reboiler condensate outlet pipe. The discharge piping of each of these traps tie into a common header and then dump into a flash tank set at 50#. Here's the issue
At low steam flow rates - specifically when we shut down the distillation train to boil the columns out, we experience hammering in the condensate return header to the flash tank, eventually leading to gasket failures.
I have to note that the condensate return header does not have a dip pipe down into the liquid level of the flash tank. Also, 4 of the 6 reboiler traps do not have check valves downstream of them. As soon as a gasket fails, and we get a large condensate leak, the hammering subsides.
I have a few theories on why this occurs, but I wanted to hear others' input and experience with this type of issue. Also I would like to know if anyone can point me in the right direction as far as a redesign of the system or things we can do to mitigate the issue.
-Mike





RE: Steam/condensate hammer at low steam load
The lack of a dip pipe into the condensate tank is definitely a point of concern.
Why is the steam load low when boiling out the columns? Is the steam not fed to the reboilers for this operation?
A sketch of the piping, roughly to scale, would allow more specific comments.
Katmar Software - AioFlo Pipe Hydraulics
http://katmarsoftware.com
"An undefined problem has an infinite number of solutions"
RE: Steam/condensate hammer at low steam load