mineral deposits

I'm having a problem with mineral deposits (most likely calcium carbonate & iron according to the company geologists) building up inside 2 SIHI water sealed liquid ring pumps used for groundwater remediation systems in remote locations that are visited about twice a week. The deposits are smooth, fine textured and appear almost ceramic . The color is rust red on the outside, black on the inside where it contacts the iron & steel components, and seems possibly somewhat translucent in between. The buildup effectively eliminates the side clearance on the impellers to the point that the shaft will no longer turn. This has happened in as little as 250 hours of operation.

Can anyone suggest an approach to preventing or treating this that does not require disassembling the pumps? Perhaps a chemical treatment that can safely be flushed through the pumps now and then?

BTW, I'm a former auto mechanic (20+ years) with no formal training or practical experience with this sort of equipment prior to coming to work for a small environmental company. I'm in a bit over my head and can use all the help I can get.

Thanks,

Dave

 

[macm]

calcium carbonate can be readily removed with acid. it is a matter of using the one that reoves the deposits without dissolving the pump. perhaps an organic acid like acetic (vinegar) would work, much like the coffee pot cleaners, which i believe are citric acid, but vinegar works too.
A sample and a little experimentation would help. Did you try calling the pump manufacturer or distributor ?
mac

 

[ChasBean1]

An acid might solve the immediate problem by cleansing, but for prevention, I would recommend softening the water using filtration or chemical addition. Disodium Phosphate is an additive that promotes soft sludge versus hard scale deposits. The soft sludge can be removed from the system by blowdown or filtration. There are demineralization or ion exchange filter mediums that should be readily available for purchase to prevent this sort of buildup.

 

[Gravy]

Mac - Thanks, vinegar seems to work, as does a phosphoric acid solution. (I had tried muriatic acid, bur it attacked the metal more aggressively than it did the scale.)

ChasBean1 - Thanks for the suggestions. Soft sludge should not be a problem. I think chemical addition is most likely more practicable than filtration, but I need to learn more. Can you point me to some suppliers?

Thanks,

Dave