How is Distilled Water made?

In the distilling process, filtered water is placed into a container and heated until it reaches boiling point and steam begins to rise from it. This steam is channelled into a separate clean container where it is allowed to cool down using heat exchangers and revert back to its liquid form.

The distilled water process is based on the principal that with the rise of the steam, the heavier elements and impurities are less likely to become part of the flow of steam and will remain in the original container.

The intention of the distillation process is to produce water free of all molecules other than hydrogen and oxygen. Depending on the purity levels required for the distilled water, the process may be repeated up to three times until an almost perfect level of purity is achieved.


In industrial applications such as ours, the distilled water is gathered in stainless steel containers, to ensure maximum levels of sanitation and purity. At every stage of the distillation process, the water undergoes tests to measure contamination levels and only when the required level is achieved is the water is bottled. The principal reason why distilled water is produced is for industrial applications where water purity levels are paramount. In some cases purity levels are required to reach almost 100%.

For general industrial use levels are not required to reach such high levels, although the quantities required are considerably more than any other application. It is only when the distilled water is used in more specific, highly technical processes such as in medicine, scientific research or in a hi-tech environment do the levels of purity need to reach such high levels as 1 or 2ppm. Producing distilled water is known for its power intensivity, which in an increasingly energy conscious environment is becoming a problematic issue. Some of the pressure has been take off and cost effectiveness increased that to advances made over the last few years advances the development of a new generation of evaporators that have are capable of considerably reducing energy requirements over single process evaporation units.

Based on the principle of thermodynamics multi-effect distillation has been designed to reduce pressure in the condensation container, meaning that the untreated water will be introduced at a considerably lower pressure. The vaporisation process then occurs at a much lower temperature considerably reducing energy costs.

A more traditional method of producing distilled water, usually in bulk, that has been around for a long time but has made a comeback in the last few years is through harnessing the power of the sun’s rays. Known as 'solar driven condensation', untreated water is fed into a container tank with a clear plastic roof, that is totally exposed to the sun's rays. The rays, over a certain period of time, cause the water to gradually evaporate. As it does the steam is then fed into another container, until it vaporises and is ready to be checked for levels of pureness. Obviously very time-consuming but extremely cost effective the solar driven condensation method is a working alternative to any power driven method as long as the levels of purity required is not too high.