Water is one of the most vital resources in the world but it’s not as easily sourced as many would think. Mass production of drinking water is easy but thanks to home water purification systems, getting water to drink is as easy as turning on your faucet at home.
It isn’t magic how water purification works. There’s a science behind it and understanding how the entire process works is important if you want to know just how much effort is put into getting drinking water right at home.
There are various types of purification systems out there. Here’s how the most common water purification system works.
This is the most common means for water purifiers. In reverse osmosis systems, water is or other solvents are passed through a semi-permeable membrane. This membrane serves as a barrier through which contaminants such as ions, pesticides, chemicals, and microorganisms are dissolved from water.
The process is simple and effective, which is why most purifiers use it.
It is mostly combined with other filters such as mechanical and absorption filters to make sure that even fewer contaminants pass through the system. As it uses force to filter the water, reverse osmosis systems also don’t use electricity which makes them highly cost-effective.
Mechanical filtration is almost similar to reverse osmosis and it’s often used in partnership with that method. It’s a basic method for water filtration. It can be something as simple as using large debris or rocks to a ceramic filter. But it can also use ultra-fine filtration to separate water fro its contaminants.
Mechanical filters come with micron ratings that determine how effective it is in filtering water. The common ratings of such filters are:
- 5 Micron – Will help remove microscopic particles such as cysts, giardia, and cyptosporidium.
- 1 Micron – Can remove particles that are too small for the naked eye.
- 5 Micron – Cna remove particles that are visible to the naked eye.
While simple and effective, mechanical filters are not the best filtration systems to use at home. For that reason, they are used in partnership with reverse osmosis systems or other more complex filtration systems for a purer form of water filtration.
Absorption filters try to capture water-borne contaminants and absorb them. Most of these filters use carbon as a means to absorb the contaminants. Carbon has a huge internal surface that it packed with small crevices that can help trap chemical impurities like chlorine which makes it an effective absorber.
As water passes through the absorption filter, all of the contaminants are absorbed and trapped within the carbon. These filters can be made up of various materials such as wood and even coconut shell.
Most domestic or home filters contain granular activated carbon (GAC) which helps reduce unwanted odour and taste via absorptions. Higher-end filters also have carbon block elements that can help with particle removal.
Sequestration involves using chemicals to isolate contaminants in water. In most cases, food-grade polyphosphate is used to help sequester calcium and magnesium minerals that are bad in high concentrations in water.
Polyphosphate doesn’t completely get rid of calcium and magnesium in water. Instead, it helps regulate the minerals within the water so that they don’t form hard surfaces.
Ultra Violet Disinfection
As the name suggests, this form of filtration involves the use of a UV lamp. The strong lights from the UV lamp kills off the germs and bacteria that are in the water which allows us to create clean drinking water. These rays can kill 99.9% of microorganisms in water which makes it highly efficient.
What makes ultra violet disinfection a standout is that, unlike chemical filtration, it doesn’t result in the microorganisms developing immune mechanisms. UV light kills off the microorganisms quickly, thus preventing them from creating any natural defence mechanisms.
It is one of the most advanced filtration technologies out there. However, it’s not as effective for removing minerals from water unlike other filtration methods.
Ion Exchange is usually used to soften hard water. It does this by exchanging magnesium and calcium ions in hard water with soft minerals like sodium. Ion exchange physically removes the hard minerals which in turn reduces limescale that would make water suitable for drinking.
Most filters that have Ion Exchange use a resin that is made using small beads. The small beads contain soft minerals which will replace the hard minerals in the water as it passes through.
Water filtration technology has come a long way. Now, there are various filtration system that allows us to produce drinking water at a mass or even at a domestic scale. It’s exciting to see how the technology will be moving forward as we hope to find ways to create more pure and even cleaner drinking water.