Pumping hazardous liquid.

[luciom]

We have a horizontal tank for storing phosphorous trichloride; a very hazardous chemical that allows for only top entry & so we use a submersible pump with mech. seal. The afore mentioned mech. seal however often fails. Are seal-less/magnetic drive submersible pumps available ? Some reputed manufacturers ? Or might there be a better option ?

 

[mucour]

It will be interesting to know if you filled a pump datasheet which will be sent to the pump vendor before purchase of the pump in question?

You have to realise that some mechanical seals make use of the liquid pumped as a source of their lubricant. Others are permanently sealed. while some needs to be provided with lubricant manually.

I believe you should discuss with any pump vendor stating the criticallity of the liquid you are pumping and asking for suitable pump with the appropriate mechanical seal.

Examples of pump vendors (EnviroTech Pumpsystems, email:clark@envirotechslc.com), (CATPUMPS,

http://www.catpumps.com)

(Ensival-Moret International S.A.,

http://www.ensival-moret.com).

 

[stressriser]

Yes,
I just designed seal configurations for pumping hazardous materials. It is known as a barrier seal and it isolates the main mechanical seal from the environment with another mechanical seal.

We have designed a housing that runs a pressurized fluid across the main seal. It the main seal leaks, there will be a pressure drop in the pressurized fluid indicating a leak before it contaminates the environment.

Also, you can buy magnetic couplings that act as a magnetic drive if you do not want to get too complicated. We sell the couplings also.

you can find a picture of the barrier seal here.

http://www.haightpump.com/newspdfs/..._containment----Barrier_Seal_Design_Flyer.pdf