How is Distilled Water made?
The process of water distillation, a purification method practiced for centuries, involves the careful separation of pure water from its impurities by taking advantage of the differing boiling points of substances.
Water distillation is carried out by placing prefiltered water in a stainless steel distillation chamber. The water is gradually heated until it reaches boiling point, which causes it to evaporate, creating steam. This steam, being free from the original water's heavier impurities, is then redirected into a separate, clean receptacle.
The condensation of this steam is facilitated by heat exchangers, which cool down the steam, enabling it to revert to its liquid state. In essence, the distillation process operates on the principle that impurities are less likely to be part of the steam flow due to their higher boiling points, hence remaining in the original container.
The primary objective of the distillation process is to yield water solely comprising hydrogen and oxygen molecules. The required level of purity can necessitate repeating the process up to three times, resulting in near-absolute purity.
The production of distilled water caters mainly to industrial applications where exacting water purity levels are paramount. For such applications, the water is collected in stainless steel containers and UV sterilised to maintain stringent sanitation and purity standards. It is subjected to extensive testing at every stage of the distillation process to monitor contamination levels. Only once the necessary purity level is achieved is the water packaged for use in food-grade HDPE containers.
In some instances, especially for highly specialised industries such as medicine, scientific research, or high-technology sectors, purity levels need to be exceptionally high, potentially reaching 1 or 2 parts per million (ppm).
It's important to note that the process of producing distilled water is known for its energy intensity, which has become a significant consideration in our increasingly energy-conscious society. In response to this challenge, technological advancements have led to the development of next-generation evaporators. These new devices can significantly reduce energy requirements compared to conventional single-process evaporation units, enhancing both environmental sustainability and cost-effectiveness.
Building on the principles of thermodynamics, multi-effect distillation has been developed to minimize energy consumption further. This innovative approach reduces the pressure within the condensation chamber, allowing the raw water to be introduced at a much lower pressure. Consequently, the vaporisation process occurs at a considerably slightly reduced temperature, further mitigating energy costs.
Furthermore, a traditional method of producing distilled water - solar-driven condensation - has seen a resurgence in recent years. This eco-friendly technique harnesses solar power to facilitate water evaporation. Here, untreated water is stored in a transparent, sun-exposed container, and over time, the sun's rays cause the water to gradually evaporate. The resulting steam is collected in another container, where it condenses and is assessed for purity levels. Although this method is time-intensive, its extreme cost-effectiveness makes it a viable alternative to power-driven methods, particularly when the required purity levels are not exceedingly high.
The process of creating distilled water leverages natural physical properties and sophisticated technology to achieve remarkable purity levels. As we continue to advance technologically and become more environmentally conscious, the efficiency and sustainability of this process will only improve.