Peristaltic pumps for waste slurries?

[MartinLe]

I'm looking at using peristaltic pumps (hose pumps) for waste slurries: TS something up to 15%, containes grit and maybe fibers ...
This is a use case where so far we are considering PC pumps. The reason I'm interested in peristalic pumps is mostly the wear on the rotor stator package, the hoses are at least cheap (unless I need to cahnge them three times as often ...). We'Ve yet to build our first waste plant with a PC pump in this specific duty, so I don't know for sure how long the wear parts last.
The duty would be to feed slurry from one tank to the next, not to feed process equipment. I think that makes the pulsation issue less severe than it could be.

Some questions I ask myself now, and that I'll ask an Albin rep in a few weeks:
- how do the pumps handle longer fibers? (My guess is quite well, but ...)
- With lots of solids, would it make sense to use a large pump with a smallish motor
- pulsation, how severe it is and what to do

I'm I wrong with my assumptions allready? What else should we be aware of? If someone can share experiences, that would be appreciated!

 

[micalbrch]

A peristaltic pump is not a bad choice for this. It can handle sand and grit definitely better (less wear) than a PC pumps, regardless what stator material one choses for the PC pump. Fibers are not a problem neither. 15 % TS is quite high. Are you sure this is correct? I do not know what kind of waste slurry that is but in a typical (municipal) WWTP 15 % TS is close to be a paste.

Pulsations become an issue the higher the pressure is. But as you are just planning to pump from one tank into another the pressure does not seem to be that high. And Pulsation dampeners can also be added later if that becomes an issue.

I would definitely oversize the pump to get it smoooth running. The grit can become a problem if the particles are big.

 

[MartinLe]

This is not WWTP sludge, this is a sludge derived from MSW. As I understand it, in WWTP sludge a lot of the water content is bound in the cells so there's less free water as a lubricant. Real data is, of course sparse (I'd love to have a student doing nothing but TS, VS and viscosity readings at all the plants we can smuggler her into), but similiar slurries I have seen where not pasty.

Our pretreatment limits the particle size to <12mm, most SS will be far smaller but individual longer vibers can be present.

If yo uwanted to destroy a peristaltic pump, what wold you pump?

 

[micalbrch]

12 mm is not small. Forget the fibers, even if they are longer. They do not matter. Peristaltic pumps can handle big particles and 12 mm are basically not a problem. The critical point are the shoes which squeeze the hose. They must be adjusted so that the hose is not destroyed when a big particles sits inside the hose and the shoe squeezes the hose. The chance that this happens is not very high but you should definitely inform the vendor about your concern. If I want to destroy a hose mechanically, I will add a lot of big and sharp edged particles to my slurry.

 

[bimr]

I would not recommend this application without a pilot test of several months. The hoses wear out quickly if continuously operating and any debris in the fluid will accelerate the wear.