Wastewater Treatment Cast Iron Pump Problem

[scottyspi]

Our wastewater treatment center provides treatment to all plant runnoff. We are a soda bottling plant where the runoff is dilute soda (ph-3.8-5.0), line lube, sugar water, sanitation caustic, facultative anaerobes aka natural flora, small fragments of plastic aluminum wood. They are centrifigual pumps with a SS impelar and cast iron housing. We have had two pumps go out that are 2 years old. On both pumps the cast iron housings have been corroded away while the SS impelar is fine. My question is with such acidic solution (ph-3.8-5.0; temp - 50-70 F) should the pump housing been made out of SS?

 

[zeusfaber]

Suggest this question might reach a more suitable audience in forum407

A.

 

[scottyspi]

thank you