Need better pump for phos acid clarifier underflow
Need better pump for phos acid clarifier underflow
(OP)
I have a problem pump that is a constant headache. It's an expeller-design centrifugal pump on the underflow from a phosphoric acid clarifier. The current pump seal will not survive in this service, mainly due to low flow and high inlet pressure:
1.5 sp. gr. phos acid
20 - 30% solids
52 feet of inlet head pressure
60 psi discharge pressure needed
13 gpm typical, 140 degrees F
The most current solution was to cut the impeller down drastically, run the pump speed up high to help the expeller seal better, and keep the discharge control valve almost closed (~10%open). Naturally this wears out the control valve quickly too. The seal package lasts about 6 weeks.
Looking for suggestions for a better pump application. Current ideas are a disc pump and a progressive cavity pump. Anything better out there?
1.5 sp. gr. phos acid
20 - 30% solids
52 feet of inlet head pressure
60 psi discharge pressure needed
13 gpm typical, 140 degrees F
The most current solution was to cut the impeller down drastically, run the pump speed up high to help the expeller seal better, and keep the discharge control valve almost closed (~10%open). Naturally this wears out the control valve quickly too. The seal package lasts about 6 weeks.
Looking for suggestions for a better pump application. Current ideas are a disc pump and a progressive cavity pump. Anything better out there?





RE: Need better pump for phos acid clarifier underflow
Have always had trouble with expeller seals unless the application is benign. There is probably a suitable flushed mechanical seal but you may have to put up with a little dilution. Stay away from cartrige type seals as they fill up with crud and are difficult to clean out.
Chas S Lewis in St Louis make vertical shaft submerged impeller phosphoric acid pumps (no seal needed) but I am not too sure of their solids capability. They would be worth a call. I have only used their sulphuric acid pumps which are brilliant even if they look a little old fashioned.
Beware of mag drive pumps as the solids could cause problems.
Cheers
Steve McKenzie
RE: Need better pump for phos acid clarifier underflow
RE: Need better pump for phos acid clarifier underflow
RE: Need better pump for phos acid clarifier underflow