Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Automatic Bullet Dewatering Option Evaluation

Status
Not open for further replies.

dezirak

Chemical
Oct 12, 2005
14
0
0
CA
Currently we have a couple of very large hydrocarbon bullets (50/50 butane/propylene ambient temp) that occasionally accumulate water.

Pump suction nozzle has a 24-36" standpipe going on one side of the vessel. Currently there is no form of water boot and no type of instrumentation that measures water level. The only current options for dewatering the bullets are to either drain to pad (unacceptable, drain till HC blow through) or line up drain line to pump suction (unacceptable, process needs to be as dry as possible).

I've looked at a few different options but am having trouble identifying what is reliable enough and somewhat cost effective. The goal is to drain the water to a lower pressure portion of the process, so some hydrocarbon breakthrough is allowable, but not much.

1. Installation of an external level bridal and addition of guided wave or capacitance probe to determined water level. Issue is no side nozzles, only top and bottom nozzles. I fear hydrocarbon accumulating on top of water level in bridal causing inaccuracies (bullets run at around 50% liquid full usually). This would be tied to a level controller or on/off valve.
2. Directly installing a guided wave or capacitance probe in the vessel (top or bottom). This would be tied to a level controller or on/off valve. I'm unsure well this set up would work with no sump/boot.
3. Draining through a baffled vessel with a level indicator on bullet side. This would be tied to a level controller or on/off valve. This would require the addition of a pressure vessel and the complication that arises from that.
4. Using a coriolis meter to detect density of fluid on drain line. This would be tied to an on/off valve.
5. Using a microwave meter ( the spool piece) in a manner similar to the coriolis meter. This would be tied to an on/off valve.

If anyone has experience with any of those potential solutions, I would appreciate some feedback, especially a comparison between option 4 and 5.

Thanks,
Dezirak
 
Replies continue below

Recommended for you

Why is drain to pad unacceptable? It is also possible to install a sight-glass or even a float valve in the drain line. The float would be designed to float in water and sink in hydrocarbon.
 
Status
Not open for further replies.
Back
Top