Clean drinking water is something much of the developed world takes for granted. At this moment, more than 2 billion people in the world do not have access to clean drinking water. That means they can’t easily cook, wash their hands, bathe, launder their clothes, clean dishes, or even take a sip of water without planning ahead.
In America, much of the water treatment and filtration is done for us before our water even leaves the tap. Still, many people have seen it necessary to go the extra mile to remove potential contaminants, odors, and foul tastes that could come from water pipes or unfiltered chemicals.
If you’re considering a water filtration system, it’s important to have a strong understanding of the different filtration techniques so that you can decide on the best system for your needs.
Understanding the Difference Between Physical and Chemical Filtration
There are two main types of water filtration techniques — chemical and physical. Physical filtration is the process of passing water through a strainer to remove large particles and impurities. Chemical filtration is the process of pushing water through a material with an active chemical ingredient. Within the chemical and physical filtration categories, there are different methods.
Water Filtration Techniques
There are a variety of water filtration methods in popular use, including:
- Distillation: Distillation involves heating water to remove impurities and collecting the condensed and cooled water in a different container. Distillation is great for removing bacteria, dissolved solids, lead, nitrates, and sodium, but it’s not ideal for removing volatile organic compounds such as herbicides and pesticides.
- Reverse osmosis: Reverse osmosis is the process of passing water through a semipermeable membrane. The membrane prevents heavy contaminants and large impurities from passing through while the water is able to collect in a different vessel. This process requires a lot of energy and equipment, but it’s ideal for removing chemical compounds such as chloride, copper, sodium, lead, chromium, arsenic, sulfate, and nitrate. Many reverse osmosis systems have additional carbon filters to address organic compounds and other contaminants that may not be removed during reverse osmosis.
- Activated carbon: Activated carbon is among the most popular methods of at-home water filtration. This form of carbon is very porous, and it acts as a sponge for impurities like chlorine-based chemicals, pesticides, and industrial solvents. It does not do much to help soften hard water or reduce heavy metal contamination.
- Ion exchange: Ion exchange is an excellent method for softening water. Ion exchange involves the process of splitting the contaminants of the water at the ionic level; it then traps all the impurities and releases sodium ions in their place. Ion exchange pairs well with reverse osmosis processes to remove the additional sodium levels.
- UV Filtration: UV light is one of the most effective ways to kill bacteria, parasites, and viruses. It doesn’t remove mineral contaminants, though.