application temperature of ortho- & sodium polyphosphate antiscalants

[CsabaOlter]

Dear Collegues,

Could someone help me out with informing me about the followings concerning household antiscalant-filled (powdered ortho-& sodium polyphosphate) inline filters:

1) What is the efficiency? To what extent does it really bind the hardness minerals to protect houshold appliances (e.g. washing machine)?

2) Is there a temperature limit until which the chemical bondage between the phosphate and the hardness minerals remain, i.e. it keeps them in solution? (I read something about keeping iron in solution by polyphosphate only on low temperatures. Does phosphates behave in the same way when binding Ca2+ and Mg2+ ?)

Thank you for your replies in advance!

Best regards:

Csaba OLTER
technical executive

ProMinent Hungary

http://www.prominent.com

 

[unclesyd]

Here is a little information on Polyphosphates in potable water. In my working working with Polyphosphates I don't remember them used for anything other that Iron control in our operating system. The max temperature of this process was 50C. We tried them in a cooling water system but they were quickly replaced.

http://www.freedrinkingwater.com/water_quality/chemical/sequestration.htm