How to Build a Water Filter
How to Build a Water Filter In An Emergency
Learning how to build a water filter is important for those moments of emergency when you need to be sure of your drinking water supply. Ideally, a household should have a portable water filter from the nearest hardware store in order to be ready for any disaster but should you find yourself caught off-guard, simply follow these tips in order to learn how to build a water filter.
1. Gather the necessary materials to build a simple, improvised and effective water filter. For this version, you will need a large container (a plastic soda bottle 2 to 3 liters in volume would be ideal), various filter materials like fine sand, coarse sand, pebbles, grass, gravel, and a cloth made of cotton. You can also use activated charcoal if it is available because it has more filtering capacity than other naturally-occurring materials.
2. To begin learning how to build a water filter, poke holes at the top of the bottle. Up to 10-12 small holes would be sufficient. Next, cut the bottom of the bottle to make a large opening through which you can pour the water to be filtered.
3. Next put your filter materials in the bottle beginning with the finest sand you could find. On top of the fine sand put your gravel beginning with the smallest stones and ending with the largerst. If you do have any charcoal you can put it between the sand and the gravel for even better results.p>
4. Put the cloth material over the bottom of the bottle to prevent any filter material from passing through with the water.
5. Pass the water through the filter and determine if it is necessary to pass it a second (or third) time depending on how clear the resultant water is.
All water filters work based on two basic principles: screening and adsorption. Use this as a guide to determining how to build a water filter should you find yourself really short of materials and you do not have access to those recommended above.
Screening is a very basic process and utilizes the concept that big materials are blocked by smaller materials. In the case of sand, the spaces between each sand grain are too small such that debris of larger size cannot easily pass through. In a phrase, you can say that only materials as big as or smaller than the spaces between filter grains can pass through with the water. Conversely, this means that the size of the sand grains determines to what extent your filter screens contaminants in the water. Fine sand is better at preventing large particles from passing through; coarse sand will only screen up to a certain extent but not as thoroughly as fine sand.
Absorption, on the other hand, requires materials with very large surface area like activated charcoal. Contaminants, even biological ones, are attracted to and stick on the surface of the charcoal grains and are separated from the water stream. By adding activated charcoal to your filter, you enhance its capability to screen more types of contaminants, even those with smaller sizes.
Learning how to build a water filter is easy if you understand the concept behind making one. It does not even have to be sophisticated; by playing with proven elementary concepts, anyone can learn how to build a water filter that can see you through the toughest emergencies and ensure a good supply of safe drinking water for you and your family.
These instructions on how to build a water filter are very general. If you have fire available it will of course make the water safer to boil it after filtering. There also many other ways to purify water so please look at other articles on our site for more information.