No registration or passwords; no pop-up ads -- just aloha, fun, & answers.
(as an eBay Partner & Amazon Affiliate earns from qualifying purchases).
Home /
T.O.C.
Fun
FAQs
Good
Books
Ref.
Libr.
Advertise
 
Help
Wanted
Current
Q&A's
Site 🔍
Search
pub  Where the
world gathers for metal finishing
Q&As since 1989



-----

Does D.I. resistivity drop with ambient air present in holding tank?




I work at an electronics company. Here at my work we have a new R.O. system with D.I. our out put is saying that we have at least one meg of res. but when I measure the resistance of the water it is at 750k ohm. Could that happen due to the presence of ambient air in the holding tank? Can some one please advise on how to also possibly fix this problem.

Thanks,

David Dadigan
electronics industry - Fort Walton Beach, Florida, USA
June 16, 2008



First of two simultaneous responses -- June 17, 2008

Carbon dioxide in the air will dissolve in the water, creating ions in the water which will increase the conductivity (e.g., decrease the resistance).

If your water is used quickly, it shouldn't be a problem. However, if the tank is vented to air with some head space and the water is stored for a long period of time, you could see this.

If this is the case, try using a storage tank without a head space. If, for some reason, you cannot do this, you might want to look into some type of inert purge gas (such as nitrogen) to keep out the problematic gases. Realize, however, that some of this purge gas may dissolve in the water; that may be unwanted.

Christian Restifo
- Pittsburgh, Pennsylvania



Second of two simultaneous responses --

Hello,

It is evident that te resistivity changes with the addition of other elements (substances). If your environment is not polluted, then your thank is contributing to this effect.

Jose Castellanos
- Minneapolis, MN, USA
June 18, 2008




(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

 
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g, Train'g
& Software


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"