How Do Refrigerator Water Filters Work?

Refrigerators are very common in our day-to-day lives in first world countries. The benefits that are provided seem obvious enough, enabling storage of perishable items and providing water that is more filtered than tap water (at least in the United States of America). But what exactly is the process for filtration in refrigerators like? It usually occurs in 3 steps: Pre-filtration, Activated Carbon Filtration & Adsorption, and Filtered Water Dispensing.

Prefiltration

The water from your home water supply is directed into your refrigerator. This step involves a pre-filter element, usually made of a porous material (tiny spaces or holes where air or liquid may pass through) to capture large particles, sediment, and other debris from the water. This pre-filter medium is often made from synthetic materials. Once the water comes into contact with this medium, the medium captures large particles by physically trapping them in small openings of the medium, blocking their movement and stopping them from being dispensed or clogging the main filter.

Activated Carbon Filtration & Adsorption

This is the main filtration stage, which includes activated carbon (a porous form of carbon) that is treated to have a large surface area and a high compatibility for absorbing substances. This type of carbon is “activated” through methods such as heat or chemical treatments. The water from the previous stage now moves on to this main filter, where it comes into contact with the carbon’s surface, causing the contaminants to stick to its surface through the process known as adsorption (the process by which a solid holds molecules of a gas or liquid as a thin film). This stage removes contaminants such as Chlorine, Volatile Organic Compounds (VOCs), compounds that lead to unpleasant taste/color/smell, and certain metals, all of which are harmful to consume by humans.

Filtered Water Dispensing

Once the water has gone through Prefiltration and the Activated Carbon Filtration & Adsorption stage, it is dispensed through the refrigerators water system, leading to cleaner and healthier water for consumption.

The Importance of Understanding Filtration

An important disclaimer I must note is that these steps of the process to filter your water via refrigerator may vary depending on the manufacturer and country of origin. Not all refrigerators are made equally or similarly, and new innovations may merge or create new steps in an effort to minimize costs or make the water have less pollutants, respectively. Regardless, refrigerators can be seen as a necessity in a house for storing food and dispensing water at a given moment, yet the average consumer remains unaware of the workings behind filtered water and may take the water filtration process for granted. While this may not necessarily be bad (after all, trying to memorize the steps of every complex product you own may be a laborious task), you can, at the very least, appreciate your refrigerator and the steps it takes to provide you with clean water for nourishment. After all, being aware of what keeps us going may lead us to appreciate how far we are in technology and standards of living.