Activated Carbon Filters
Using Activated Carbon Filters, is a method of water purification that uses activated carbon to remove contaminants and impurities from our drinking water.
Basically there are two types of carbon filters:
1. Granular Activated Carbon (GAC)
2. Solid Block Activated Carbon (SBAC)
In general, solid carbon block activated carbon filters are more effective at removing a larger number of contaminants, based upon the increased surface area of carbon.
Each piece of carbon is designed to provide a large section of surface area, in order to allow contaminants the most possible exposure to the filter media.
One pound of carbon contains a surface area of approximately 500.000 m² (125 acres).
This carbon is generally activated with a positive charge and is designed to attract negatively charged water contaminants.
Carbon filters are most effective at removing chlorine, sediment, and volatile organic compounds (VOC's) from water.
They are not generally effective at removing minerals, salts, and dissolved inorganic compounds.
Typical particle sizes that can be removed by activated carbon filters range from 0.5 to 1 micrometers (microns).
Granular carbon blocks removes particles from about 5 microns and I would say that is not fine enough to produce clear drinking water for you.
Look out for a high quality Solid Block Activated Carbon Filter System !
The efficacy of a carbon filter is also based upon the flow rate regulation.
The slower water is able to flow through the filter, the more contaminants are exposed to the filter media.
 |
| Photo by Najib Kalil on Unsplash. |
Actually carbon filters are not a new invention as most companies propose, carbon has been used for several hundred years and are considered one of the oldest means of water purification.
Historians have shown evidence that carbon filtration may have been used in ancient Egyptian cultures for both air and water sanitization.
2000 B.C. Sanskrit text refers to filtering water through charcoal (1905 translation of "Ousruta Sanghita" by Francis Evelyn Place).
The first modern use of a carbon filter to purify potable water occurred in 1862.
Carbon filtration was further advanced in the mid 1970's when carbon powder was first manufactured into a porous block form for drinking water use.
Currently, carbon filters are used in individual homes as point-of-use water filters and, occasionally, in municipal water treatment facilities.
They are also used as pre-treatment devices for reverse osmosis systems and as specialized filters designed to remove chlorine-resistant cysts, such as giardia and cryptosporidium.
So lets have a closer look at this two Activated Carbon Filter Systems:
Granular Activated Carbon Filters (GAC)
This type of filter uses lose activated carbon granules which removes some chlorine, organic contaminants, some particular matters and some unpleasant odors and tastes.
But this filter type has some problems built in.
Because of the large pore size of the loose carbon granules, contaminated water will channel between this loose granules and that's not the best idea to filter fine particles out of the water.
Sometimes the deposited contaminations in the filter get dumped in the drinking water what produces a reverts effect and pollute the drinking water with toxic materials, what we actually like to filter out.
Advantage of GAC filters:
simple, inexpensive, reduces some chlorine and particular matter, improve test and odor, do not restrict water flow, simple maintenance, no electricity required, do not waste water, do not remove dissolved minerals like calcium, magnesium, potassium what improves the taste of the water.
Disadvantages of GAC filters:
channeling, that means water flow around the carbon granules and some water will not get filtered at all.
Some of the GAC filters use by far too big carbon granules in the size of 1mm, what is of course a joke, everything passes trough this medium.
Cannot be used with hot water, hot water would release immediately big amounts of trapped contaminants, not so good for you, I guess :-)
GAC filters are also known to become breeding grounds of bacteria, what is also not what you like to achieve with your water filter system.
Solid Block Activated Carbon
This Activated Carbon Filters are manufactured from specially treated, activated, fine carbon powder, what is compressed under enormous pressure to form a solid carbon block.
The pore size is mostly 0.5 to 1 micron, what reduces many contaminants like arsenic, MTBE,pesticides, herbicides, chlorine, chlorine byproducts, parasitic cysts, asbestos, and many more.
At the end of this page I present you a list from contaminants what should be removed from a Top End Activated Carbon Filters .
This small pore size also eliminates the problem of channeling and bacteria growth.
The area from a carbon block is much bigger compared to a GAC filter and it outperforms the GAC medium by far, because the absorption area and time is much bigger, so it can absorb much more contaminants.
The carbon blocks do not need any electricity or high pressure and can be used in an emergency by siphoning the water trough them.
They are a little more expensive as GAC filters, but they are reducing an incredible amount of contaminations and produce save, clean drinking water for you.
If you like to purchase a water filter system, please
check your selected activated carbon filters at NSF International
and see if your chosen Activated Carbon Filters are certified by them.
This will guaranty you, that the product is manufactured under the rules of NSF and also performs under the criteria of NSF.
Please do not even consider to buy Activated Carbon Filters what are NOT certified by NSF !!!
WARNING !!! Please do not use hot water with Activated Carbon Filters , they are NOT designed for this purpose !
Activated Carbon Filters will not remove soluble salts, fluoride and cadmium.
Some (I know of only one product) specially formulated carbon blocks will remove Arsenic, what becomes a problem now in many areas.
In my opinion, this Activated Carbon Block Filters are the way to go.
There are only a few cases where an RO system is needed to produce save, clear drinking water for your family.
Please do not get shocked from this list, all the contaminants removed with this Activated Carbon Filters does not mean that all this contaminants are in YOUR water !!!!
SAMPLE - NSF certified product - data sheet
ALACHLOR*>98%
ARSENIC (pentavalent As (V); As (+5); arsenate @ 6.5 pH >99.9%
ARSENIC (pentavalent As (V); As (+5); arsenate @ 8.5 pH >95.8%
SASBESTOS>99.9%
ATRAZINE* >97%
BENZENE*>99%
BROMODICHLOROMETHANE (TTHM)* >99.8%
BROMOFORM (TTHM)* >99.8%
CARBOFURAN (Furadan)* >99%
CARBON TETRACHLORIDE* 98%
CHLORDANE >99.5% 0.04 +/-10%
CHLOROBENZENE (Monochlorobenzene)* >99%
CHLOROPICRIN* 99%
CHLOROFORM (TTHM)* (surrogate chemical) >99.8%
Cryptosporidium (CYST) >99.99% minimum 50,000/L 99.95%
CYST (Giardia; Cryptosporidium; Entamoeba;Toxoplasma)>99.99%
DBCP (see Dibromochloropropane)* >99%
1,2-DCA (see 1,2-DICHLOROETHANE)* 95%
1,1-DCE (see 1,1-DICHLOROETHYLENE)* >99%
DIBROMOCHLOROMETHANE (TTHM;Chlorodibromomethane)*>99.8%
DIBROMOCHLOROPROPANE (DBCP)* >99%
o-DICHLOROBENZENE (1,2 Dichlorobenzene)* >99%
p-DICHLOROBENZENE (para-Dichlorobenzene)* >98%
1,2-DICHLOROETHANE (1,2-DCA)* 95%
1,1-DICHLOROETHYLENE (1,1-DCE)* >99%
CIS-1,2-DICHLOROETHYLENE* >99%
TRANS-1,2- DICHLOROETHYLENE* >99%
1,2-DICHLOROPROPANE (Propylene Dichloride)* >99%
CIS-1,3- DICHLOROPROPYLENE* >99%
DINOSEB* 99%
EDB (see ETHYLENE DIBROMIDE)* >99%
ENDRIN* 99%
Entamoeba (see CYSTS) 99.99% minimum 50,000/L 99.95%
ETHYLBENZENE* >99%
ETHYLENE DIBROMIDE (EDB)* >99%
**Percent reduction reflects actual performance of PRODUT NAME product as specifically tested (at 200% of capacity).
Percent reduction shown for VOCs* reflects the allowable claims for Volatile Organic Chemicals/Compounds as per Tables. Chloroform was used as a surrogate for VOC reduction claims: the Product actual reduction rate of
Chloroform was >99.8% as tested (at 200% of capacity).
Furadan (see CARBOFURAN)* >99%
Giardia Lamblia (see CYST) >99.99% minimum 50,000/L 99.95%
HALOACETONITRILES (HAN)*
BROMOCHLOROACETONITRILE 98%
DIBROMOACETONITRILE 98%
DICHLOROACETONITRILE 98%
TRICHLOROACETONITRILE 98%
HALOKETONES (HK):*
1,1-DICHLORO-2-PROPANONE 99%
1,1,1-TRICHLORO-2-PROPANONE 96%
HEPTACHLOR* >99%
HEPTACHLOR EPOXIDE* 98%
HEXACHLOROBUTADIENE (Perchlorobutadiene)* >98%
HEXACHLOROCYCLOPENTADIENE* >99%
LEAD (pH 6.5) >99.99% 0.15 +/- 10%
LEAD (pH 8.5) >99.99% 0.15 +/- 10%
LINDANE* >99%
MERCURY (pH 6.5) >99.99% 0.006 +/- 10%
MERCURY (pH 8.5) >99.99% 0.006 +/- 10%
METHOXYCHLOR* >99%
Methylbenzene (see TOLUENE)* >99%
Monochlorobenzene (see CHLOROBENZENE)* >99%
MTBE (methyl tert-butyl ether) >96.6% 0.015 +/- 20%
POLYCHLORINATED BIPHENYLS (PCBs , Aroclor 1260)>97%
PCE (see TETRACHLOROETHYLENE)* >99%
PENTACHLOROPHENOL* >99%
Perchlorobutadiene (see HEXACHLOROBUTADIENE)*>98%
Propylene Dichloride (see 1,2 -DICHLOROPROPANE)*>99%
SIMAZINE* >97%
Silvex (see 2,4,5-TP)* 99%
STYRENE (Vinylbenzene)* >99%
1,1,1-TCA (see 1,1,1 - TRICHLOROETHANE)* 95%
TCE (see TRICHLOROETHYLENE)* >99%
1,1,2,2- TETRACHLOROETHANE* >99%
TETRACHLOROETHYLENE* >99%
TOLUENE (Methylbenzene)* >99%
TOXAPHENE >92.9% 0.015 +/- 10%
Toxoplasma (see CYSTS) 99.99% minimum 50,000/L 99.95%
2,4,5-TP (Silvex)* 99%
TRIBROMOACETIC ACID*
1,2,4 TRICHLOROBENZENE (Unsymtrichlorobenzene)*>99%
1,1,1-TRICHLOROETHANE (1,1,1-TCA)* 95%
1,1,2-TRICHLOROETHANE* >99%
TRICHLOROETHYLENE (TCE)* >99%
TRIHALOMETHANES (TTHM) (Chloroform; Bromoform;
Bromodichloromethane; Dibromochloromethane)>99.8%
TURBIDITY >99% 11 +/- NTU 0.5 NTU
Unsym-Trichlorobenzene (see 1,2,4-TRICHLOROBENZENE)*>99%
Vinylbenzene (see STYRENE)* >99%
XYLENES (TOTAL)*>99%
CHLORAMINE as Aesthetic Effect (As Monochloramine) >98.3%
CHLORINE as Aesthetic Effect 99% 2.0 Mg/L +/- 10% > or = 75%
PARTICULATE, (Nominal Particulate Reduction, Class I, Particles 0.5 TO <1 UM Class I > 99%
Comments
Post a Comment