If you manufacture, use or sell water treatment chemicals then you've probably come across magnetic water treatment equipment, sometimes referred to as magic gadgets. These magnetic gadgets claim to do away with the need for treatment chemicals.
Does magnetic water treatment work?
In the UK alone the formation of scale and hardness salts in industrial process plants where water is heated or used as a coolant is estimated to cost in the region of £1 billion per annum.
You may also not be too surprised to learn that there are several web sites dedicated to the effectiveness or otherwise of these magnetic water treatment devices. What these sites appear to say is that the jury is out on whether the gadgets work, but they are clear on is that water treatment chemicals, when used correctly, do work.
Magnetic water treatment
A chemist at the Simon Fraser University, Canada suggests that the reason these magic gadgets may sometimes appear to work can be explained by the chemistry of water. When silica is present in water it can form colloidal particles whose electric double layer when distorted by an external magnetic field tends to adsorb calcium and magnesium ions thus inhibiting their precipitation onto heat transfer surfaces. The role of silica within the process is claimed to be the reason why, on some occasions magnetic devices don't work, whilst on others they do.
It is interesting to bear in mind that most scientifically valid studies have not shown the technology of magic water treatment devices to be effective for scale control.
Non-chemical scale control v water treatment chemicals
A team from 3M tested non-chemical scale control agents versus traditional water treatment chemicals in a once-through system. They tested them on a shell and tube, water/steam heat exchanger and found that no magic device significantly reduced the amount of scale formed compared to the controls whereas water treatment chemicals reduced scale formation almost completely.
There seems to be lots of evidence demonstrating that correctly applied water treatment chemicals are effective when used by competent people, under the right circumstances. There is however less scientific evidence to suggest that magic gadgets work.
If you wish to investigate the issue of magnetic water treatment further we can recommend the following web site:Simon Fraser http://www.chem1.com/CQ/magscams.html