Installing a pump in series

[axx1]

Hi,

I am planning to install a heat exchanger on an existing water line. The water is pumped from a tank through an anion resin unit and then to a another tank. The heat exchanger will be installed after the resin unit.

I want to install an in-line booster pump on the water line to accomadate the pressure drop across the heat exchanger. I cannot increase the size of the existing pump due to pressure limits on the resin unit.

What design consideration must be made w.r.t. cavitation, water hammer, mech seals and gaskets. The suction pressure of the booster pump will be 4 bar at 60m3/h and discharge pressure of 7 bar.

Thanks.

 

[pmover]

the simple solution is to generate a "system curve". that is, a curve that shows the head losses vs flow for the proposed system.

my first thought was a 3-bar dP across the exchanger seems excessive (not knowing type, flow rates, etc.). regardless, find a pump that is a good hydraulic fit for the system, based on the "system curve".

cavitation, make sure there is sufficient NPSHa for the proposed pump.

water hammer, any quick closing valves or sudden/rapid changes in flow in the water system? if so, address them. one that comes to mind is the shutdown of the booster pump.

mech seals, be sure the pump seal is designed to withstand inlet pressures and pumpage you specified. avoid getting pump information from a sales rep - go to pump mfg directly.

hope this helps. good luck!

-pmover