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Additional Magnetic Water Softening Information

Magnetic Water Softening And Scale Control

There is a long history of the promotion of magnets to alleviate the "hardness" of mineral-containing waters, and particularly to control the deposition of scale in teapots, evaporators, and especially in boilers.

The majority of magnetic water softening devices claim to work by causing the carbonate salts that would ordinarily form adherent scale deposits to precipitate as small particles within the water instead.

This would also presumably reduce the concentration of the calcium and magnesium ions that react with soaps to form insoluble scums.

Promoters of this technology refer to the experiments of Klaus Kronenberg who observed a change in the morphology of calcium carbonate crystals formed upon evaporation of a solution that had been passed through a magnetic field.

One of the few scientific studies reporting some success with magnetic scale control suggests that the presence of silica in the water is required.

A more recent and detailed study by Coey has found that magnetic treatment encourages the growth of aragonite, the less-stable (more soluble) form of calcium carbonate.

Most water-treatment engineers who have investigated Magnetic Water Softening treatment in industrial settings report negative results, and there are no confirmed reports of successful magnetic water softening installations in the reputable scientific and engineering literature.

Most scientists who have looked into magnetic water softening remain very skeptical, as they tend of be of any field for which there is no obvious theoretical model and in which quantitative and reproducible results are hard to come by.

(A very similar situation arises in studies of whether power transmission lines contribute to leukemia.)

Scientists who might otherwise be qualified to investigate magnetic water softening also tend to be put off by the stigma the field has acquired due to the exaggerated claims made by some of its adherents and the widespread promotion of various worthless applications involving magnets.

Sometimes the subject of magnetic water softening reminds me of those Monty Python apartment towers that were able to stand up only as long as the residents had faith in them!

The widespread circulation of scientifically untenable "explanations" describing how passage of water through a magnetic field causes oppositely-charged ions to coalesce does little to inspire confidence that the promoters of these devices know what they are talking about.

(For a brief debunking of this theory, see the description of the notorious Federal Technology Alert on magnetic water softening

A lot of articles appearing in the technical (as opposed to peer-reviewed scientific) literature are written by people whose apparent ignorance of physics and chemistry leads them to concoct unrealistic theories of how magnetic water softening might work.

For a very thorough review of the published literature on Magnetic Water Softening for scale control, see "Magnetic amelioration of scale formation" by John S. Baker and Simon J. Judd: Water Research 1996 30(2) 247-260.

An internal report (PDF format) by a group of engineers at the U.S. Dept of Energy's Lawrence Livermore Laboratory describes a carefully-done series of experiments that failed to reveal any beneficial effects of magnetic water softening at one of their water treatment facilities.

In contrast, there are a very few papers that appear to be of scientific quality (described in the references section below) that provide some support for magnetic water softening under certain conditions.

It is important to bear in mind, however, that most scientifically valid studies have not shown this technology to be generally effective for scale control, suggesting that the conditions under which magnetic water softening can work are still not understood.

For those contemplating the purchase of a magnetic water softening device, my advice is that you establish definite, testable, criteria to define what "it works" means in your application, and then make your purchase only from a company that is willing to offer a performance guarantee based on these criteria.

As an example of some of the crackpot chemistry that is adduced to promote these devices, consider this paragraph from the site below, every statement of which is false:

"When water, or any stream of atoms, enters a powerful magnetic field, it physically changes in the same way atoms change when run through particle accelerators used by physicists.

In effect, the water is ionized. Negatively changed oxygen ions are stripped from stable water molecules and are freed to perform a number of tasks. Among other things, the altered water can dissolve scum lines, help stabilize pH, kill algae and microorganisms, and release stains and odors from fabrics.

It also serves to limit cases of eye and skin irritation, improves water solubility, helps reduce corrosion of metal parts in the system by adding needed electrons to the water, and makes the water act soft while retaining acceptable water hardness." ?

... or this one that manages to mangle any number of the laws of physics:

As water moves through the induced magnetic field, the static charge on the water molecules is changed from negative to positive due to current being generated by the moving water (Faraday's Law).

The current produced by the flow also causes some water molecules to ionize (dissociate), forming hydronium ions.

And I love the German product that sells magnetically-treated water that the consumer can use to "inoculate" water in kettles or steam-irons against scale formation. ;)

Further references on magnetic water treatment:

"Water: its structure and importance" is a comprehensive and informative Web-based resource on water science by Martin Chaplin of South Bank University (UK).

It includes discussions of the effects of magnetic fields, and of homeopathy.

In 2002, a group of Polish scientists published the results of a very careful study showing that MWT can be effective under certain conditions:

This is one of my favorites...

The Effectiveness of a magnetic physical water treatment device on scaling in domestic hot-water storage tanks. C. Smith, P Coetzee and J. Meyers. Water SA 29(3) 2003.

These South African authors have produced what strikes me as a very well-done study, one of the few that reports scientifically credible evidence for the effectiveness of MWT.

Their series of experiments in which one of two parallel heaters was fitted with a permanent magnet device showed scale formation reductions varying over a rather wide range (17-70%), with an average of 34%.

Tests of non chemical scale control devices in a once-through system. G.J.C. Limpert and J.L. Raber. Materials Performance, Vol. 24, No. 10, 40-45, (1985), Oct.The abstract of this 10-year study at the 3M Corporation reads as follows:

"Experiments were conducted in a test heat exchanger system to evaluate 10 non chemical scale and corrosion control devices. These devices may perform either by electrostatic, magnetic, electronic, or catalytic mechanisms.

Chemical tests also compared results with non-chemical systems to insure the test conditions were not so severe that scale prevention was impossible.

Water from a single deep well known to cause calcium carbonate scale when heated was used in all tests. The test heat exchanger was a two-tube shell and tube with steam applied to the shell side.

Water flow was either in series or parallel through the two tubes, depending on the desired test conditions. No device tested significantly reduced the amount of scale formed, compared to the controls. Proprietary chemicals containing phosphorous reduced scale formation almost completely."

Is this a great informational website that will make you wonder if Magnetic Water Softeners are a scam?
I would suggest that you really do some of your own research regarding magnets, however, I have provided a small piece of research information regarding the subject.

The [in]famous Dept of Energy report regarding Magnetic Water Softening:

This 1998 document regarding Magnetic Water Softening which has since been withdrawn from circulation was a Federal Technology Alert from the U.S. Department of Energy that presented a suspiciously uncritical case for magnetic water softening.

It provided no references to support the claims made, and the explanations of how magnetic water softening devices are supposed to work were scientifically naive.

The report was apparently compiled by the Battelle Research Institute, which may have farmed out some of the work to the Pacific Northwest National Laboratory.

Because this report is widely cited by the magnet merchants (and copies are still apparently in circulation; it is worth commenting on.

We are told that the magnetic field deflects the ions in the water, causing them to move in opposite directions normal to the direction of flow so that ions of opposite charge collide more frequently, increasing the chances that they will combine and precipitate out before they have a chance to form scale or do other bad things.

The "So Called" science behind magnetic watering softening:

Charged particles moving in a vacuum are indeed deflected by magnetic fields, but ions in solution are too massive (remember that they have a primary hydration shell of H2O molecules attached to them) and too locked into the "cage" created by the surrounding hydrogen bonded water to be able to undergo any significant deflection as they pass by the magnet.

Magnetic water softening (If this effect were really operative, the efficacy of the process would be a function of flow rate, and no mention is made of this in the article!) It should also be pointed out that oppositely charged ions encounter each other all the time through random thermal motions, and even form ion-pair complexes such as CaCO3° which can exist indefinitely as stable entities without precipitating.

This report also mentions an electrostatic method of water treatment in which "a surface charge is imposed on the ions so that they repel instead of attract each other." This is ridiculous.

It is worrisome that the U.S. Department of Energy, which also looks after nuclear reactors and nuclear weapons, should have its name associated with such sophomoric science.

This is likely not an uncommon result of what happens when research organizations go grubbing for government money for projects in which neither they nor the sponsoring agency have scientifically competent personnel available to review the work.

In this paper which is often cited as the classical original investigation of magnetic water softening, the author describes the changes in the morphology of calcium carbonate crystals formed by evaporation of water that has been passed through a sequence of several magnetic fields.

The effect of the treatment is to change the crystals from a dendritic form to smaller disk-shaped forms (that presumably are less likely to form a scale-- but this is not tested.)

The curious thing is that the water seems to "remember" the treatment-- evaporation and crystallization were carried out in a field-free environment.

The need for the water to flow past a succession of magnets (up to 16) at a specific velocity prompts Kronenberg to suggest that "the interaction between the magnetic fields and the hydrogen bonds is amplified to the breaking point by resonance."

The idea is that the breaking up of the (H2O)n complexes somehow releases dissolved ions that promote nucleation of the smaller crystals. The observed effect lasts for up to two days.

It is difficult to assess this paper. His experimental results are interesting (there are photographs of the crystals), but much of the interpretation strikes me as suspect and I doubt that it would pass muster in a refereed Chemistry journal. An attempt to reproduce these results might make a good science fair project.

Dispersion destabilization in magnetic water treatment - This recent article by Lipus et. al. (J. Colloid Interface Sci. 236 60-66 2001) is a theoretical study that suggests a possible mechanism for the kinds of effects reported by Kronenberg and which are commonly cited as the basis of magnetic scale prevention.

The essence of the article is that an external magnetic field can produce a distortion of the ionic atmosphere surrounding incipient calcium carbonate particles in such a manner as to facilitate their coagulation before they can deposit as scale.

One of the relatively few carefully done quantitative studies reporting positive results with magnetic water softening for scale control in actual installations (domestic hot water tanks) can be found in this PDF document. The work was done at a South African university and was sponsored by the Water Research Commission of South Africa. It was published in the journal Water SA 2003: 29:137.

Magnetic effects on surface tension of water:

The belief that magnetic fields can reduce the surface tension of water has become almost an urban legend that is widely promoted by various magnet merchants, despite the very small amount of evidence that has been amassed during the 100 or so years that the effects of magnetic fields on matter have been studied.

Owing to the intense scientific interest in the properties and structure of water, one would expect that any convincing evidence that the surface tension of water can be influenced by magnetic treatment would make its way to one of the mainline chemistry journals.

So far, this has not happened; what few reports there are tend to be in rather obscure publications which deal mainly with other fields and are probably not subject to review by water chemistry experts.

Two recent articles illustrate this problem:

Young I. Cho, a mechanical engineer at Drexel University, reported (Int. Communications in Heat and Mass Transfer 32 (p 1-9) 2005 ) a reduction in surface tension of up to 8% in hard water that had been treated by a 0.16 T permanent magnetic field; use of a 600-hz alternating field gave similar reductions. Unfortunately, this article does not provide enough information to assess the statistical validity of the results, which, it should be emphasized, do not apply to pure water. Also, this work depended on capillary rise observations, which although theoretically proportional to surface tension, do not actually measure it.

A more recent study by Amiri and Dadkhah offers a good bibliography of earlier work in this field. Their careful study, which involved direct surface tension measurements (using a tensiometer rather than capillary rise), led them to conclude that the changes they observed were likely due to the effects of impurities, and that no meaningful conclusions about the effects of magnetic fields on surface tension can be drawn from existing studies, including those of Cho mentioned above.

Taking the most optimistic reports into account, it seems clear that the rather small magnitude of these effects makes them unlikely to be of significance in most practical applications.

So... Until I see something that is more definitive, my own position is that there is no convincing scientific evidence that magnetic treatment can significantly reduce the surface tension of water :)

The bottom line? Be really sure of what your trying to accomplish. Some only look at the price and make their decision upon the price, you should look past the price here because you will get what you pay for:)

Magnetic Water Softening is very popular because people really believe they can get a Quick Fix in solving their water hardness problems. Filter Water Direct offers several "Science Backed" Calcium Reduction Systems that really work without installing magnets on your pipes.