dP Meter and Seal Pots

[NewMechanicalEngr]

I have an application that includes a horizontal pipe with orifice flanges in a piperack that is about 15 feet in the air. The product is an Offgas and we need the transmitter mounted at grade, which is against the norm of mounting transmitters in gas service above the process taps.

Would this be a good application for seal pots?
I was thinking of sloping the lines upward from the orifice meter up to a pair of seal pots, which would be filled with Glycol. Tubing would be connected from the seal pots and drop nearly straight down to grade where it would connect to the transmitter manifold.
Does this seem reasonable?
Is there a length limit on the filled impulse lines?

Thanks in advance for taking the time to read and/or reply!!!

 

[roydm]

Is the offgas condensing?

If it's reasonably dry you might get away with running a couple of half inch lines from the orifice plate to the ground with a normally closed valve at the bottom. At the transmitter height a tee fitting connected to the transmitter. Any stray moisture would run down past the transmitter to collect in the lower portion of the pipe to be drained out on a regular basis.

Another possibility is to bleed in a tiny flow of gas to keep the inpulse lines clear.

 

[bamboo123]

this link probably could give enough information of your answer :

http://www.flowcontrolnetwork.com/articles/offshore-orifice-plate-impulse-line-arrangement

 

[roydm]

As I was saying, figure 3 or 4 of Bamboo123 link