Home water purification systems compared

We firmly believe that water distillation is the best system for home purification of drinking water. First - let's recap on distillation: Water is heated up until it evaporates, leaving the contaminants behind. The steam is led through a cooler where it condensates back to extreme purity distilled water.

Water purifications compared

Because water is heated to the boiling point in the distiller, bacteria and harmful micro-organisms will be killed. Other contaminants will remain in the boiling chamber as the steam carries the absolute pure water out through the condenser. Distillation effectiveness is well over 99%, quality of the produced water is not affected by the amount of contamination in the source water, pressure or water temperature. Quality is consistently the same as long as the distiller is still working, giving you peace of mind that what you drink is as absolutely pure as the first time you ran your distiller.

Now let's have a look at competing technologies for home water purification.

Reverse osmosis water purification systems

Water is forced through a semi-permeable membrane under pressure. This process is actually the well known natural process of osmosis but run "backwards", a technique frequently used in desalination plants.

The membrane has not got pores as we would normally describe them but instead it is built from of microscopic thickness polymer layers. Reverse osmosis filtration can remove particles as small as individual ions. Bacteria and virus are both larger than this and will in theory be filtered out. However, due to imperfections in the membrane, some can be carried over and if you want to be safe you need to combine an RO system with something like UV or ozone treatment for best effect.

One major disadvantage to reverse osmosis systems is that they will waste 3-4 times the amount of water they actually filter. The waste water cleans out the membrane so if you try to make a more efficient system, you will shorten the life span of the membrane. This is fairly costly to replace.

Activated carbon water filters

This is maybe the most common type of home water purification and activated carbon water filter units are sold everywhere in supermarkets.

Activated carbon is carbon that has been heated up to high temperatures in the absence of oxygen supply. Think of it a bit like making popcorn, but with carbon. Because of the extreme surface of activated carbon, there will be a lot of adsorption by molecular attraction when a liquid passes through the carbon. This has the ability to filter out some contaminants. 

A new and fresh carbon filter will be very good at removing some of the organic contaminants but pretty useless when it comes to removal of biological or toxic metal contamination.

When using an activated carbon filter it is important to allow enough contact time (at least 7-15 minutes is recommended) for best adsorption. There is a risk of bacterial growth in the filter itself if left for a while, sometimes that time can be as short as within a week. For proper use, it would be ideal to pour boiling water through the filter before use but since most simple filters are plastic, that is often not possible.

Because of these factors, it is difficult to know what the efficiency of the activated carbon filter is at any given time except when it is brand new. 

Links

Distilled water - Wikipedia
How it's made, all about purity, distilling and where it is used.

Distilling vs deinonizing
What, in essence, is the difference between distilled and deinonized water?

Water treatment methods
and many other water health issues compared by the US environmental protection agency.

Residuals in distilled water
A good discussion on possible contamination left when distilling.

Tap water or distilled water
What is the difference, physically?

Drinking pure water is important to keep your body in balance and with some diseases or conditions like bowel problems, hemorrhoids, and many others it becomes even more important.

Pure water without any toxic components is also good for avoiding a number of diseases such as rheumatory arthritis, inflammations, virus infections and other opportunistic diseases attacking when the immune system is low.

Everything you ever wanted to know about tractors - machinery for men.