How is distilled water different from filtered water?
The main difference between distilled water and filtered water is that there is some kind of process involved in producing distilled water, whereas with filtered water, as it name suggests, water simply goes through a non mechanical filtering process only.
Untreated water is continuously fed into a stainless steel boiling vessel. The water is heated to boiling point until steam begins to rise and then channeled into a separate container where it will revert back to its pure liquid form. With the rise of the steam, the heavier and impure elements in the water cannot become part of the flow of steam and remain in the containers during the filtration process.
The purpose of distilling water is to fabricate water levels that are free of all molecular waste, and will contain just elements of hydrogen and oxygen. The distillation process has been known to be repeated contingent on the water purity levels required.
Water can also be filtered to all levels, with its starting level can be much lower that distilled water. That is because filtered water can be used in a multitude of applications from agriculture to industry, while most of the water that is consumed will have gone through some kind of filtering process. Depending on the application the levels of filtration can be very low or can be surprisingly high. For example, in agriculture, water can even have been recycled from sewage and applied to certain agricultural products such as citrus fruits which are thick-skinned. Municipal and domestic gardens are another place where you will find some forms of recycled filtered water being used to irrigate. Recycled water needs to go through several stages of filtration before it can be used. Recycled water will generally have its own piping system to totally reduce the possibility of it being drunk.
The usual methods for filtration can either be of the water is passed through a fine gravel or through a series of retorting rotating rings. In either method is very important to keep the filters clean. Cleaning filters at this level usually done by method known as back flushing. When black flushing takes place the flow of the water into the filters is reversed for a predetermined period until all the foreign bodies that they have gathered in the filters have been flushed away. It is very unusual for any form of recycled water to be used in industry.
Generally industry will pay reasonable prices to receive very clean water, usually potable from source, and depending on the nature of the industry will ensure that has been filtered to the highest possible level. Many large industrial plants have installed what are known as closed-circuit systems. These systems are set up so that any wastewater is possible filtered and their recycled within the system. Most domestic drinking water is filtered to higher levels and usually with a percentage of chloride and fluoride introduced. Whilst filtering at high levels can be expensive, the process is nowhere near as costly as distilling water, meaning that the vast majority of water used in the developed world has undergone some level of filtration while distilled water remains very much in the minority as far as quantities consumed.