Charcoal Water Filters

Charcoal Water Filters are one of the important types of water filtering technologies. They utilize charcoal as the filtering media. The charcoal absorbs impurities as the water passes through. This type of filter almost comprises 95% of domestic filters. They are relatively economical, simple to install, and filter out the most deadly of contaminants, like Guardia and Cryptosporidium. The functioning of latest charcoal filters are enhanced by the use of activated silver, which provides extra antibacterial protection. However the minerals in solution can still permeate a charcoal filter.


Use of Charcoal
The charcoals used in the water filters are "activated charcoal". Some times it is also called 'active charcoal' or 'activated carbon'. Activated charcoal is a form of charcoal, which has an exceptionally high surface area. One gram of activated carbon/charcoal has a surface area of approximately 500 m2. It is obtained from a variety of carbonaceous source materials, like coconut husk, wood, coal, etc.

Activated carbon is broadly classified in two types on the basis of their physical properties. One is powdered activated carbon and other is granulated activated carbon. However for filtering purpose, granulated activated carbon is used. It has a relatively larger particle size compared to powdered activated carbon and therefore presents a smaller external surface. It is determined by nitrogen gas adsorption and includes a large amount of microporosity. In a charcoal water filter, as the water passes over the charcoal, the granules trap large water contaminants and prevent them from passing through with the water.

Charcoal Water Filters is basically made from the husk of coconut. It acts as an absorbent and absorb most of the impurities, often toxic, when the water runs past the charcoal in the water filter.

Function of Activated Silver
The charcoal water filters, on the average, work efficiently from six to nine months when used regularly. They are considered a perfect water filtering system. Though they remove most of the harmful and unwanted particles from the water, but their functioning is further enhanced with the introduction of activated silver in the latest filters. The activated silver provides antibacterial protection for your water.

Working of Activated Carbon Filters
The activated carbon or charcoal removes contaminants from water by two principal mechanisms, one is absorption, and other is catalytic reduction. In absorption, some of the contaminants are absorbed by the the charcoal. Catalytic reduction is a process involving the attraction of negatively-charged contaminant ions to the positively-charged activated carbon. Residual disinfectants, like chlorine and chloramines are removed by catalytic reduction, while organic compounds are removed by absorption.

Contaminants Removed
The charcoal water filters are efficient in removing the deadliest contaminants such as giardia and cryptosporidium. The reason for mainstay of charcoal water filters in the water filtering market is that they can handle these contaminants along with a lot of other ones like:

Volatile Organic Chemicals (VOC)	Tri-halomethane (THM)
Pesticides	Solvents
Herbicides	Radon
Chlorine	Benzene

They are reasonably effective at removing some, but not all, heavy metals. Densely compacted carbon block filters are capable of removing particles as small as 0.5 micron, including Cryptosporidium, Giardia, turbidity and particulates.

If the concentration of contaminant, like Iron and Manganese are high, then it become quite difficult for the carbon filters to remove them. Carbon filters are not effective in removing the dissolved inorganic metals or contaminants, like antimony, arsenic, asbestos, barium, beryllium, cadmium, chromium, copper, fluoride, mercury, nickel, nitrates/nitrites, selenium, sulfate, thallium, and certain radio nuclides.