While we assume that the water we drink is safe enough, in reality, it isn’t. Even the cleanest looking water can have impurities. That is where a water filter would be a handy option. However, have you ever given a thought to what exactly water filters are made up of and how do they work? Let us check out how they work and help you consume clean drinking water further in this post.
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How do Water Filters work?
Well, the question of how to do water filters work can only be answered based on the types of different water filters. Different types of water filters have different types of functioning mechanism. Ideally, water filters come five different mechanisms. The working principle of these filters will completely be dependent upon the type and technology they use for the purpose.
Mechanical Water filters
Mechanical water filters are designed to clean physical impurities in the water. The technology involves blocking the sediments, dirt and other contaminants through the use of a barrier. There are multiple barriers used right from a simple mesh to ceramic filters. High-end mechanical filters may also make use of ultra-fine pores to clean out pathogens.
The efficiency of the filter and the removal of contaminants contained in the water depends on the micron rating of the barrier used.
The following list should provide you with a basic idea of what to expect –
- 5 micron – Removes the dust and other particles that are visible to human eyes
- One micron – Removes particles that are too small and need a microscope to be visible.
- 0.5 micron – Removes cysts and other impurities
The sedimentation technique for filtering the water has been one of the most common types that are being used for years. The typical household pitcher water purifier is perhaps the best example of this type of water purifiers.
Absorption type water filters
This method involves the absorption of the contaminants through the user agents that absorb them. Commonly used mediums are activated carbon and activated alumina. This is one of the best options for taking care of waterborne contaminants.
Activated carbon water filters are best for reducing bad odours and taste of the water. Expensive filters in this genre can come with carbon block filters. These filters carry a better micron rating and are efficient enough in handling particle removal.
There is also an additional option available that involves ceramic filters. The ceramic filters come with a huge number of small pores in it. Any impurities larger than the pores is kept outside, and the pure water is made available for your consumption. Ceramic water filters have been observed to be effective in handling bacteria and protozoa.
Ion Exchange Water Filters
These water filters rely on chemical properties of the contaminants to clean your drinking water. More than for disinfecting water, this method is ideally used for softening the hard water. The ion exchange option involves exchanging the magnesium and calcium ions in the water with the sodium ions through the use of ionizing agents.
In sharp contrast to the other options, the ion exchange option physically removes the hard minerals from the water. The technique uses an ion exchange resin which comes in the form of beads. The resin normally utilizes sodium ions and will normally need to be recharged periodically. In those regions where too much sodium can be an issue, hydrogen-based resins are used.
Reverse Osmosis is one of the best water filtering techniques. It involves the removal of dissolved inorganic solids from the water by moving it through the semipermeable membrane. The water is pushed under pressure, and thus the contaminant is left behind.
In most of the recent range of water filters, the Reverse Osmosis as a procedure can be found along with other filtering mechanisms like mechanical and absorption techniques. Reverse osmosis may or may not use electricity to force the water through the membrane. Because reverse osmosis or RO filters make use of a multi-stage cleaning process with other filtering methods, they tend to be on an expensive side. In any case, these are the best options where a water purity level of over 90 per cent is expected.
The system can be a little heavy and bulky in size – more so since it does come with multiple stages with pre-filters, post filters, and other elements. However, it has been considered to be one of the best water filter technologies and helps remove heavy metals and other harmful chemical elements. They can be one of the preferred choices for under the sink or countertop filters.
UV Water Filters
This is one of the water filter techniques which of a more recent origin. These filters come with a high degree of cleaning and filtering mechanism. The technique used in the filtering of water involves the use of high-frequency light to remove the impurities.
The water filter makes the water flow through a glass element. A stream of UV rays is passed through the glass element and this will help you get purified drinking water where all the microorganisms are killed. The technique involved in killing the organisms is innovative and unique. The UV rays mutate the DNA of the microorganisms in such a way that they get killed. However, water filtering technology needs the energy to operate it and will not work without the use of electricity.
In practice, the recently made available branded water filters come with a multistage multi-platform functionality where you have a combination of reverse osmosis, UV radiation and absorption technique rolled into one single application. Though such a technique can make the water filter bulky, it improves the efficiency of the system as a whole and improves the quality of the water you consume.
That was a brief introduction to how water filters work. The actual functionality of the water filter you own may differ slightly depending upon the construction and other details. In any case, the basic principle under which these water filters work should remain just as has been explained here.