cjw32
Nuclear
- Apr 17, 2009
- 12
We have a diaphragm metering pump designed to pump around 80L/hr. We are pumping nitric acid. The nitric acid is in a 5000L tank standing about 3m. The pump sits about 1m from the base of the bund. The pump has 1/2" inlet and outlet, but it is connected by 10mm pipe to the process inlet line where the nitric acid is mixed with the process liquor by an in-line mixer.
We observed the pump operates most of the time at around 80-90L/hr. However, we have observed some batches where the pump has been injecting at approximately double the flow rate i.e. 160-200L/hr.
Even when we operate in normal conditions the pump has a slight metalic sound. We have replaced the pump with a similar model and observed the same characteristics.
We adjusted the stroke length to a fixed position to ensure consistent injection.
The recirculation line where the nitric injects into is at approximately 2.5 Bar.
The pump is a lewa ecodos metering pump.
Any ideas?
We observed the pump operates most of the time at around 80-90L/hr. However, we have observed some batches where the pump has been injecting at approximately double the flow rate i.e. 160-200L/hr.
Even when we operate in normal conditions the pump has a slight metalic sound. We have replaced the pump with a similar model and observed the same characteristics.
We adjusted the stroke length to a fixed position to ensure consistent injection.
The recirculation line where the nitric injects into is at approximately 2.5 Bar.
The pump is a lewa ecodos metering pump.
Any ideas?
