"Magic" water descalers?

[ichaj]

I have read about some devices (electrical or magnetical) that fit outside water pipes and help to prevent scale gathering on the surface of the pipework. May this be the solution for the water used in steamboilers and exhausting condensers, instead of consuming large amounts of salt for descaling water in classic resin descalers? These devices are pretty expensive considering the technology they deploy but are cheaper than salt and energy loss due to scale coating in pipework.

Is it true that these devices really work?

 

[TD2K]

In a word, scam, in my opinion.

 

[krecian]

We have used both magnetic and so called 'electric' external as well as in-line devices.

Dont trust them. It will be big disappointment.

 

[hacksaw]

Suggest that you read a copy of "De Magnete" by Gilbert before you use magnets to purify water. TDK has the best advice on the matter.

 

[25362]

Has anybody installed these magnets in his plant or home to tell of the results ? Theories (weird) on their mechanism and effectiveness abound, but has anybody seen in fact that hardness doesn't follow the laws of solubility when exposed to electro-magnetic fields ? Until seriously confirmed facts on the benefits of these appliances are shown, one should reasonably consider them a "scam on scum".

 

[kenvlach]

There was a long thread on this subject about 3 months ago. Many links to reviews & studies. To summarize, all presently marketed devices seem to be in the ‘snakeoil’ category.

The primary scientific claim is that scaling due to calcium carbonate may be deterred by some energy input which favors one crystalline form over another (aragonite vs. calcite). The calcite scales out on the interior walls of the pipe, while the aragonite stays suspended in solution, and can be removed during boiler blowdown, etc. There is ~negligible difference between the free energies of formation of the the crystal types, so some energy input at the right frequency may make the difference. Whether this would be energy-efficient and whether an external device would work on a metal pipe remain to be determined.

One review is at

http://www.sbu.ac.uk/water/descal.html

A review by the Committee for the Scientific Investigation of Claims of the Paranormal
is at

http://www.csicop.org/si/9801/powell.html

 

[saxon]

ichaj, We installed one of these things once on a test basis in a small chilled water loop, just for grins and giggles. It didn't work worth a .... Actually the sky hooks the Stress Group has come up with seem to work a lot better.

saxon

 

[bwi]

Last spring our local community college district installed two identical Evapco cooling towers at one of their campuses. One tower is using a non-chemical "pulsing power" system for water treatment and the other tower is being treated with traditional chemical treatment (phosphonate/polymer inhibitor with oxidizing and non-oxidizing biocides). Inspection of the chiller tubes this fall showed no scaling, bio-fouling or corrosion in either of the associated chillers. The chemically treated tower was operated at approximate 3-3.5 cycles of concentration (based on conductivity). The non-chemical treated tower had equal or higher cycles. But visual inspection alone is inadequate to prove that the system "is working".

Next month we are going to begin an evaluation of these installations that will include corrosion coupons (ASTM D2688-94), independent lab HPC bacteria tests, data logging of system parameters and other tests. It should be interesting to see the results. Full corrosion results will take a year to confirm.

There is a lot of snake oil out there regarding non- chemical treatment. The chemical companies have a vested interest to ensure all the "non-chemical" treatments are considered snake oil. However, some units do work and should be considered by informed purchasers. What is needed is an independent commercial validation similar to the Cooling Tower Institute's efficiency ratings of cooling towers.

Dean

 

[bwi]

If you want more information about non-chemical treatment for cooling tower applications, check out this link:

http://www.smud.org/education/cat/cat_pdf/PulsePower.pdf

 

[chemproject]

Hello,
There are a number of reports which have investigated the theory behind magnetism and its decontamination properties. There is no real concrete evidence to prove that it actually works. Many of the companies that sell these products are independent. I have'nt heard of a global market leader in this type of industry yet.

The hardness is supposed to be reduced by the magnetic fields, but the calcium and magnesium will still be present in the water, with the same dissolved mineral concentration.

For further information:

http://www.csicop.org/si/9801/powell.html

 

[GenB]

GOOd topic.
I am very involved in small boilers. I seen a couple of this things some 25 years ago. I inmediately made up my mind about them. it was an imposibly, by logic that the little pipe would take away scale from water. I know some companies have lost tons of money for trusting the seller. Believe me this pipe things are advertised heavily, some of them even have patents. I confronted a mfr.(nuhaus corp) at a trade show a few years back and he was steaming after I told him that his discaling pipe stinked.
The patent claim is that the electric side of it breaks apart the calsium and other sediments in the water.
that's it. The patent, The lab work may be true but in minimal quantities say 1% and what do you do with the other 99% of harness.
please use a reliable water conditioner and do test your water daily for zero hardness.
ER

 

[Nosey]

One firm also claims that these units improve fuel efficiency on cars, boilers and other fired heaters. Yet they could not explain how a magnet could effect a non-polar substance such as the hydrocarbon stream.

I fully agree with all of the above - snakeoil.

 

[moltenmetal]

Never trust a patent as proof of function. Though they may throw out aggregiously stupid applications, the patent department won't generally dispute your claims, and they certainly won't test them- you can patent any non-functional device you wish, if you have the money.

 

[JoeDenny]

HOGWASH TECHNOLOGY, says a WQA certified water specialist!