Ethylene Glycol detection in condensate stream for heat exchanger

[FluidME]

Is there a method or system for continuous detection of water-ethylene glycol solution leakage into the condensate stream of a GW/Steam heat exchanger?
Would a conductivity sensor be suitable for the above purpose?

 

[1503-44]

Level indicator in the glycol tank, or keep track of the refill rate. Temperature monitoring might work.

OR...

https://www.kemtrak.com/pdf/brochure/ethylene-glycol-detector-kemtrak-web.pdf?_t=1717409015

https://oilinwatermonitors.com/monitoring-hydrocarbon-leaks-steam-condensate/

https://www.environmental-expert.co...g-hydrocarbon-leaks-in-steam-condensate-16077

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[btrueblood]

Yes, a conductivity sensor would likely detect glycol leakage (compared to pure condensate, and provided no volatile corrosion inhibitors are used that might(?) also form conductive ions in the condensate).

1504, glycol is more of an alcohol than a hydrocarbon, not sure if the hydrocarbon detectors would work - except glycols that have been treated with fluorescent tracers (most automotive glycols have this added, it's why they look yellow/green). I'd have to look to see if pure glycols fluoresce...and a quick web search says no.

 

[1503-44]

Thanks. I wasn't sure.

"If you have to keep on adding it, its leaking." reasoning has worked for me more than a few times and not just for glycol.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[FluidME]

1503-44
Monitoring the level in the GW expansion tank is definitely a way. But there are other units in the system as well.
For eg: LNG vaporizer utilizing the GW closed circuit, and SW-GW heater as well. The level could be due to leakage anywhere else.

The idea is to continuously monitor the condensate of any glycol contamination and provide feedback to a three-way valve, which normally passes the condensate to an atmospheric drain tank or otherwise to bilge well in-case of contamination.

 

[FluidME]

betrueblood,
I looked on the web and found that the conductivity of Fresh water-Ethylene glycol solution is less than 0.5 ppm. So not sure, whether a conductivity sensor would give very accurate results.

 

[Latexman]

Would a conductivity sensor be suitable for the above purpose?

I’d say no. Pure water has no electrical conductivity. EG has low electrical conductivity. You will be at the mercy of the level of ions in your system. I think if it did work, it’d be a PITA with a lot of false indications.

Good Luck,
Latexman

 

[georgeverghese]

Assuming condensate is much less corrosive then MEG-water, I'd suspect corrosion is from MEG-water. What kind of water do you use to make up this solution ?
Biocide and oxygen scavenger doped, and expansion drum is N2 padded ?

What type of HX ? TEMA configuration ? Materials of construction ? Got a process/mechanical datasheet ?

 

[pierreick]

Hi,
Take regular samples (routine) and check with your lab the techniques available to detect organic compounds.
Chromatography could be an option.
Pierre

 

[FluidME]

We are planning to use colored glycol water and install an observation tank in the condensate line.
But we need a continuous auto monitoring, with feedback to three-way valve to lead the condensate to bilge well in-case of contamination.

 

[pierreick]

Hi,
Go back to the lab and ask them to check whatever technique is suitable! Consider also to talk to the company selling chemicals for your boiler, for sure they have experience.
Another possibility is to call Mettler toledo or others about their ability to support you.
Why do you need a continuous monitoring, seems to me your HX is in poor condition?
Pierre