Views:6 Author:Site Editor Publish Time: 2017-07-16 Origin:Site
Carbon filters have been used for several hundreds of years as a method of filtration, mainly as a means of purifying water. To this day carbon filtration remains the most common technique of water purification. However, carbon filtration has applications beyond water purification, and is also found used in industrial gas processing, purification of sugarcane, in the recovery of precious metals, and, finally, what we are most interested in as hydroponics growers…filtering air.
To understand how carbon filters work, first and foremost it’s important to know that carbon filters contain what’s called activated charcoal. You may have heard about it under different names like activated carbon, activated coal, or carbo activatus. Activated carbon is charcoal that has been heated or otherwise treated to increase its adsorptive power.
How is activated carbon produced?
First, the carbon must be sourced. Commonly, materials like nutshells, coconut husk, peat, wood, coir, lignite, coal, or petroleum pitch are used. Then this source of carbon can be “activated” through 2 different processes: a physical reactivation or a chemical activation. They are both very complex processes that involve very high temperatures (above 600 degrees) and the addition or exposure to various gases and chemicals to assist the ‘carbonization’ process.
What are the properties of activated carbon?
The use of specialised manufacturing processes results in highly porous charcoals that have surface areas of 300-2,000 square metres per gram. These so-called active, or activated, charcoals are widely used to adsorb odorous or coloured substances from gases or liquids. -
carbon filters work through adsorption
Carbon filters remove odour molecules via absorption
Why use a carbon air filter?
One of the challenges of indoor growing can be the creation of unwanted odours, and one of the benefits of using a carbon air filter is the removal of these odours from air as it extracted from the grow room. The activated carbon inside the filter will “absorb” unpleasant smells and air impurities s the extracted air passes through, or to be more specific they will be trapped into the pore structure of the carbon molecules.
How long will a carbon filter keep working?
Carbon filter hydroponics have a lifespan expectancy of 18 months to 2 years, although this will be dependent upon many factors such as whether the filter has been in constant use and what humidity the filter has been exposed to and if the pre-filter sleeve has been changed regularly to prolong to prolong the active function of the carbon. The obvious test is the most important one here: if smells are increasingly seeping out, then, it is almost certainly time to replace the filter!