Difference between filtration and water purification.
The water we drink must be clean in all aspects, without unpleasant colors or odors, and in addition, it must be beneficial to our health. Unfortunately, water is not available to everyone, which leads to health problems. Science has made great strides in providing us with the best methods to obtain clean water, free of contaminants that could affect human health. To ensure that drinking water is healthy, many people install a filter in their home or a purification system.
Am I looking for a filter or a purifier?
First of all, one must know how to differentiate between the terms filter and purifier. It can be difficult to know the difference between filtration and water purification, mainly because of the wat products are marketed under those terms. There may be two companies that manufacture products that do substantially the same job, but label their products differently. One may call a product a water purifier, and the other a water filter. To understand what these types of products do, it is necessary to understand how the industry considers the two terms.
What is purification?
Of the two terms, purification seems to be the most confusing concept.
The term purify means to eliminate what is not desired, therefore, a product that intends to purify water means that its purpose is to make water drinkable (suitable for human consumption). In other words, it means eliminating what is not desired, or what at certain levels could represent a health risk (minerals, salts, organic matter, metals, etc.).
Most purification systems use activated carbon to adsorb contaminants. The carbon purifiers, adsorb organic molecules present in the water. Other types of purifiers include ultraviolet light lamps to remove microorganisms, ion exchange resins to retain minerals or metals, and distillation, to name a few.
What is filtration?
The concept of filtration is easier to understand, as it is a concept we are more familiar with, when applied to certain activities of daily life. filtration is a physical process that uses a filter element or screen that retains solid particles while allowing a fluid to pass through. The act of filtration can be exemplified as when we use a strainer in the kitchen to prepare food.
The two most common water filtration systems are sediment filters and membrane filters, and often these two systems are combined for better filtration. Sediment filters generally retain elements according to size from 1 to 100 microns. Membranes can retain microscopic contaminants smaller than one micron, some viruses, bacteria, dissolved pharmaceuticals, and even unwanted minerals.
What is the difference between purification and filtration?
The difference is that a purification is the one that removes unwanted impurities from the water by adsorption, distillation, UV radiation or ion exchange as already mentioned; and a filtrationprocess, only prevents the passage of solid particles through a filter or screen, while the liquid flows through it. Very fine membrane filters (microfiltration, ultrafiltration or Reverse osmosis RO) can retain viruses, bacteria, salts and minerals.
In summary, when there are natural or added elements either dissolved or microscopic in the water as a contaminant, it is considered to be a purification, and when there are sediments or solid impurities, it is considered a filtration.
Normally in homes and industry, these two systems are combined to improve water quality, placing filters as a first step and purification systems as subsequent steps.
We can conclude that, since both processes are combined, the term purification seems a bit confusing, so some companies avoid using the term in labelling. This is one reason why many water treatment systems are labelled as filtration, rather than purification. It is more common to call a product for purifying water “water filter”, because that is how it is commonly sought, but the correct term should be “water purifier”.
In the following link you can see the conventional Water Purification Process.