Blowdown overflowing sump...

[mikecabs]

I am currently working on a problem at a power plant where a sump is overflowing due to the cold start of two units at the same tim. The original sump was not designed to handle the blowdown that has recently been rerouted there. I have been trying to get some measurements on how much blowdown is occuring but don't think that this is possible. the only thing that i could think of was to go out to the site and create some kind of floatation device to measure the time that it takes for the fluid levels to rise and the distance, etc. does anyone have any ideas? I have some drawing s that give flow rates of blowdown but believe that these are durign steady state. any ideas?

 

[BigInch]

Its possible that the flowrates you see on the drawings represent "steady state" during a unit start or stop, but the best way to find out (or verify those) is to measure what you see happening now. How fast the pit fills is a good way to do it.

http://virtualpipeline.spaces.msn.com

 

[vpl]

I don't know if this is possible (i.e., is the area around the sump accessible), but an easy thing might be a couple people with radios and stop watches. People in communication with each other via radio. Stopwatch started when the blowdown is started and stopped when the sump overflows.

Just a thought

Patricia Lougheed

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[mikecabs]

I can access the sump but while blowdown is occuring there is lots of steam and hard to see. I'm thinking of making some type of floatation device attached to a pole and measure the height and time during blowndown. I have concrete drawings so know the area of the sump. I think that this is pretty much all I can do at this point.

 

[Artisi]

BigInch is on the mark with this, measure the time to fill the sump and measure the overall time that blowdown is taking place- from there you can extrapolate the sump size needed. ie, if it takes 2 minutes to fill the sump and blowdown is for 4 minutes - you need to double the sump volume.