Another form of purified water is deionized water. The process to deionize water is less expensive than distillation. Special chemicals are added to the water, which bond to the dissolved salts. These remove the chemicals, leaving behind water that is very pure, even free of most bacteria. Deionizing water takes less time, and requires less work, but for human consumption, you’re more likely to see distilled water in stores than deionized water.
There are a variety of filtration methods to achieve purified water. Not all methods result in the purified water that you can get from distillation or deionization. Some trace elements may not be filtered out using other processes, but generally most purified water sold for drinking has lower levels of chemicals than does normal tap water.
For years, there have been arguments over whether drinking filtered water, as opposed to tap water, is beneficial. In areas where high levels of unsafe compounds have been noted in water, it may be far better to choose purified water. In emergency settings, it can be imperative to drink only bottled water, if sewage has contaminated the regular water supply.
Sometimes, the trace minerals in tap water can be beneficial. You may lose calcium, fluoride, and a variety of salts when you drink purified water instead of water from the tap. There are arguments for and against the consumption of purified and/or tap water, and most people should take a look at these arguments before making a decision on which water to drink.
There is less argument about the use of purified water for various machines and in a variety of chemical applications or laboratory work. Some scientific experiments require water that is exceptionally pure in order to be certain that any trace elements remaining don’t affect experiments or testing results.
In various industries, water that has most metallic salts removed via deionization or distillation can be preferred so that mineral buildup doesn’t occur in machines or their constituent parts.
Even on the home front, you might want to use distilled or deionized water in your coffee pot, iron, or humidifier to prevent minerals from collecting in these devices and reducing the life of these appliances.