Water Filter Basics
One of the most important items that you can have in your emergency supplies is a water filter. There are a variety of ways to clean water and make it safe to drink: boiling, distillation, reverse osmosis, deionization, chemical purification and filtration. In this post, I want to explain the basics of micro porous filtration or more simply said “how a water filter works”. At the end of the post, I have included some excellent reference articles from Wikipedia that include more detailed information on the topic for those that are interested.
Many people use water filters in their homes. They are attached to their faucets or sometimes are used with a water pitcher. Typically, these water filters use some sort of activated carbon filter, micro porous filtration or a combination of the two to purify the water. Portable water filters use the same methods to clean water. Portable water filters are used by hikers, the military, survivalists and other people that are in harsh environments. They allow you to clean suspect water and make it safe to drink.
Here is how a portable water filter works. Most portable water filters use a ceramic cartridge inside to clean the water. At one end of the filter, dirty water is brought in through a pumping action. The pump then forces the water through the ceramic cartridge. The ceramic cartridge is designed to filter contaminants that are 0.2 micrometers or larger. Basically, the filter will allow through water molecules and not much else. Major pathogens and contaminants such as Giardia lamblia, Cryptosporodium and other bacteria will be filtered out of the water. Giardia is commonly found in most back country water sources such as lakes, rivers and streams. Once the water is forced through this ceramic cartridge, it comes out the clean end of the water filter, purified and ready to drink. Pretty simple process. Most portable water filters will pump about a liter of water per minute, depending on the clarity of the water.
The advantages of a portable ceramic water filter:
- Allows for quick access to safe, purified drinking water wherever you find a water source.
- Removes debris from the water is it is filtered.
- Portable and simple to use and maintain.
What a portable ceramic water filter can’t do:
- Remove viruses from water sources such as hepatitis A and rotavirus.
- Remove chemicals all chemicals from the water.
- Remove salt from the water.
Portable water filters like the MSR Miniworks or the Katadyn Combi are great portable water filters and highly recommended. Keep in mind, that ceramic water filters, while designed for outdoor backpacking, hiking and military use, still need to be handled carefully. If dropped or damaged, the filter can get very small hairline cracks in it that will allow larger molecules to get through the filter and make it not safe to use.