Mechanical Seal For Lime Milk Pump

[Mike1180]

We are selecting pumps for a lime milk recirculation system.

I've done many such systems for mining process, pumping lime milk with 15 to 18% hydrated lime. Mechanical seals are always used with no seal water nor quench water. Never got any negative feedback and I witnessed some working perfectly.

Now, the lime content is 20%. Some people worry that the mechanical seal will not get proper cooling.

Your thought? Any experience?

 

[MJCronin]

Talk to a mechanical seal vendor ... ask about his experience..... What is the vendor and model of the seal in question ?

Go back to the plant manger for the lime milk systems that you have done. Ask him to take 10 minutes and physically take the seal temperature with a remote device. Is this temperature at 15 to 18% lime anywhere near the maximum temperature permitted for the seal ?

Tell "some people" who ask obviously pointed and difficult questions to keep their mouths shut... or you will do the same to them

MJCronin
Sr. Process Engineer

 

[Compositepro]

I don't think that cooling is the issue. The issue is particles getting between the sealing surfaces. I've experience with a new mechanical seal failing in minutes with a slurry of polymer particles. Had to go with a flushed seal.

 

[pierreick]

Hi,
My experience with milk of lime in the chemical industry ( water treatment and distillation both on soda ash process ) is flushed seal for the reasons explained by Compositepro.
You need to collect the water polluted with lime and recycle it somewhere in your process .
Concentration Cao (g/l) : 130 g/l for Water treatment and 260 g/l for distillation .
Pierre

 

[Mike1180]

Thanks to all you responded!

Hope to hear more references!

To MJCronin: Good approach, but I do not keep contact with the past projects. Actually people keep moving so easily lose contact with them.

To Compositepro and peirreick: Mechanical seal specially designed for slurry service works fine with some light slurries. It can last for a couple of years if maintained properly.

 

[pierreick]

Hi,
Thanks to share with us the reference of your mechanical seal designed for slurry .
regards
Pierre