Scaling without calcium?

[arguellesmanuel]

Hi, im writing from venezuela.

I need to know how is posibble that im having scaling in my evaporative condenser if my water feed is:

TDS: 320 ppm
Total Hardness: <10 ppm
pH: 7.2
bicarbonates: 190 ppm
Silice: 29 ppm.
Temp: 77 F.

i work the condenser at 4 cycles max.:
in the basin have:
TDS: <1300 ppm
Total Hardness: <50 ppm caco3
pH: < 9.1
bicarbonates: <800 ppm caco3
Silice: <120 ppm.
Carbonates: <100 ppm caco3


the residual of ortophosfathes is near to 12 ppm. and the dispersant its near of 24 ppm. (continue dosification) and the critic temperature is near to 95 Fahrenheit.

Thanks.

 

[GarySCWSVI]

"Scaling without calcium"?? Not only is Ca present in your water but also silica and most likely sulfates. All potential scale causers. A good source of information can be found in the "Nalco Water Handbook". Another factor in scale formation would be the flow velocity within your system. Chapter's 4 and 21 of the Nalco Water Handbook should be of interest to you. You should be able to find it in a local library or buying one through a Google search for it.

Gary Schreiber, CWS VI
The Purolite Co.

 

[bimr]

The scaling is not just calcium, it is calcium carbonate.

If you want to avoid scaling, you also have to be address the alkalinity level, which in your case is very high.

Most industrial users use sulfuric acid to control the alkalinity level, keeping the alkalinity below 200 mg/l. Adding acid keeps the pH down by destroying alkalinity.

 

[leigstam]

Hi,

First thanks Gary for the wonderful source "Nalco Water", it realy has all the info needed. I agree that keeping the alkalinity level low will solve much of the problem in the future.

Susan

http://www.handiquip.com