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Why are DM and SOFT Water Used?

07/09/2007 1:28 PM

pls anybody say why we use DM and SOFT water in chemical plant

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#1

Re: Why are DM and SOFT Water Used?

07/09/2007 1:59 PM

Soft water allows for faster and more complete mixing of products.

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#2

Re: Why are DM and SOFT Water Used?

07/09/2007 3:22 PM

Minimizes contamination of product.

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#3

Re: Why are DM and SOFT Water Used?

07/09/2007 3:22 PM

The calcium, CACO2, magnesium and other minerals might react or bind with the active chemicals rendering unwanted results.

The ph of the dolomitic water in my area is above 12. Diluting an acid with that will result in the formation of salt(s)

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#4

Re: Why are DM and SOFT Water Used?

07/10/2007 3:56 AM

The terms 'hard' and 'soft' relate to the tendency of the water to form scale on heat transfer surfaces. CaCO3, MgCO3, CaSO4 and MgSO4, found in most natural waters, are only marginally soluble, and their solubility decreases with rising temperature.

The simplest way to reduce the tendency to form precipitates is to pass the 'hard' water through an ion-exchage softener so as to substitute Na+ for Ca++ and Mg++, and Cl- for CO3-- and SO4-- (the solubility of NaCl is high and largely independent of temperature).

Further treatment of the softened water to produce a water low in minerals can have important economic advantages in terms of reducing the 'blowdown' frequency of steam generating plants, a practice that, unavoidably, causes a loss of energy at the boiler house.

Water treatment is an involved business and gathering some advice and background information from the suppliers of water treatment at this works is recommended.

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#5

Re: Why are DM and SOFT Water Used?

07/10/2007 9:30 AM

This question could be answered as detailed as one want.

Basically, the use of treated water is to minimize both, piping and metal corrosion, and process contamination. Depending on the type of process, the treatment varies but most of them are designed to remove mineral salts (Ca, Mg) to avoid their precipitation downstream.

If you need further information, please ask.

SaC.

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#6

Re: Why are DM and SOFT Water Used?

07/10/2007 11:09 AM

In wafer fabs there is the ever ominous >1 micron particles -- the buggers. So all 'seed' impurities as well as actual particles are removed as allowed.

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#7
In reply to #6

Re: Why are DM and SOFT Water Used?

07/10/2007 11:24 AM

"In wafer fabs there is the ever ominous >1 micron particles -- the buggers. So all 'seed' impurities as well as actual particles are removed as allowed."

In that case use triple steam distilled water.

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#8
In reply to #7

Re: Why are DM and SOFT Water Used?

07/10/2007 11:53 AM

Negative Ghost Rider. Guess again?

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#9

Re: Why are DM and SOFT Water Used?

07/10/2007 8:39 PM

SOFT is a folksy term=easy lathering with oil based soaps.You can use as good as you can get- no big harm done.

DM -demineralized is serious business based on MORE exact technical understanding of scale forming in High Temperature boiler tubes and drums. You need to remove the last vestige of mineral ions. If you do not-- the boiler tues will scale up inside,block the heat transfer from metal to water/steam--and you will melt the boiler tube/s

How to?-look up the Treatises

Double/Triple Distillation may still not do!

Melting Snow from Himalayas/Alps--might--but mind the contamination from Bottles/piping.

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#10
In reply to #9

Re: Why are DM and SOFT Water Used?

07/10/2007 10:20 PM

"Double/Triple Distillation may still not do!"

May not do for some applications BUT analytical chemists doing nuclear materials procedures in a National Laboratoy were overjoyed with the new double distilled over the single distilled water the had become accustomed to.

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#11

Re: Why are DM and SOFT Water Used?

07/11/2007 11:20 AM

H2O - please note such terms as distilled, filtered, DI, pure and ultra-pure. For more on Ultra Pure specs please see current wafer fab specs ie; Intel and Samsung.

ohh teh hours of testing! what fun it was. And did I mention profitable?

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#12

Re: Why are DM and SOFT Water Used?

07/11/2007 8:46 PM

Depends upon the application. For heat exchange purposes, demineralized water will not leave behind deposits that can clog the pipelines. For the actual chemical processes, the dissolved minerals can affect the purity of the product or affect the efficiency of the process.

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