Static accumulation of conductive fluid in non-conductive pipe

[yene]

I am asking this on here because I cannot find a conclusive answer anywhere.

I have acetone flowing for ~100 feet from a glass-lined vessel to a steel grounded vessel. The pipe is 2" diameter and lined with polypropylene, thus making it non-conductive.

My understanding is that acetone, despite being a conductive liquid, will generate charge via "Streaming Current", and won't be able to dissipate it until it reaches the steel grounded vessel. How can I find out whether or not I need to implement bonding or grounding measures?

Initially I calculated the Streaming Current, I[sub]s[/sub], then squared it and multiplied by the resistance of acetone, R, (Length of pipe x Specific Resistance / Cross-sectional area), then divided by 2 to calculate power generated. (Extensions of Ohm's Law, I believe)

Then I multiplied by the time it took the acetone to flow through the whole pipe (i.e. t = d/v) to calculate the Energy generated. (Is this the correct time I should be using? Or is it the total time that there is acetone flowing through the line, i.e. if the pump continuously runs for an hour, does t = 3600s?)

Then I compared Energy generated to the MIE of acetone.

Does my method make sense? Or am I missing something? It makes sense to me, but electrical concepts like current/power/resistance/potential do not represent my area of expertise. Does anyone have any resources that can lead me to a conclusive answer? Even NFPA and a bunch of other resources I've looked at discuss the topic at length but give no conclusive answer to my particular question.

Thanks to anyone that can help me out.

 

[jari001]

Take a look at thread378-91957, there's some resources that may help you better analyze your situation.

 

[yene]

Thanks for the reply. I just read through the thread and while it is informative, it doesn't quite answer my question from a quantitative perspective. I'm trying to determine whether I even need to take any measures to avoid a static ignition hazard. Additionally I am not sure to what extent some of the mentioned solutions (e.g. dip pipe) help prevent the problem. Especially for a plant that is already in the construction phase - I don't know how viable an option something like that would be.

 

[hacksaw]

By conductive, you need to specify the conductivity.

You also need the fluid velocity, fluid temperature, pipe diameter, etc.

 

[yene]

I have those properties

Conductivity = 6000000 pS/m
Fluid velocity is 1 m/s through 1.75 inch pipe. Fluid temperature should be about room temp.

Another thing I should mention is that the acetone is mixed and agitated in a glass-lined tank for some time right before it gets sent through this pipe I'm referring to. Is there a way to quantify the max amount of energy generated via static accumulation from that procedure?

 

[hacksaw]

You should not have any problems at 1 m/s as long as you have submerged discharge in the receiving vessel.