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Cleaning Water with CarbonFiber
What is CarbonFiber ?
”Recovering a Beautiful Water Environment with CarbonFiber !”
Carbon fiber is a “fibrous carbon substance having a fine graphite crystal structure” which is composed mainly by carbon and manufactured by carbonizing acryl fibers, oil, and carbon by a special heat treatment process. It is generally said to be a “light, strong, corrosion-resistant” advanced functional material. It is widely used in diverse applications, taking advantage of its combination of properties as a lightweight materials with excellent mechanical properties, and its excellent properties as a carbon material.
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CarbonFiber used for use as a water purification materials (as a contact
media) |
CarbonFiber which is used for use as a water purification
materials are given a special surface treatment. It is PAN type (manufactured
by carbonizing polyacrylonitrile which is manufactured to cause the fibers
to expand in water, different from general industrial use. Carbon fibers
for water purification consist of clusters (bundles) of 12,000 ultra-fine,
7μm filaments.
 Attention
Please note that the carbon fiber for genera lindsutrial use is sold for
water purification, however it is different from CarbonFiber product given
a sizing treatment for water use.
As for CarbonFiber which is given a special surface treatement, sizing
agent dissolves in water and each fibers expand in water. The carbon fiber
for general indsutrial doesn't expand in water because it uses epoxy type
sizing agent. There is a significant difference of effect between them.
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Water purification using carbon fiber is economical and effective method.
And it is low environmental impact.
Active biofilm are formed by high bioaffinity of carbon fiber, and its
microorganisms decompose contaminants.
CarbonFiber activates microorganisms and gather fishes. Carbon fiber exercises
seaweed bed function.
Functions of CarbonFiber
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Mechanism of water purufication |
Water purification by CarbonFiber is performed by pollutant capturing
ability from large specific surface of CarbonFiber's ultra-fine filaments
and biofilm formed by effective microorganisms decompose pollutants. This
mechanism of water purufication is a biofilm treatment method which is one of the wastewater
treatment method using CarobonFiber as a contact media.
Each fibers of CarbonFiber expand in water.
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Pollutants and microorganisms in water are adsorbed.
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Adhered microorganisms form an active biofilm and decompose pollutants.
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CarbonFiber become a habitat for laying eggs of fishes
by activating microorganisms |
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| When immersed in water, a water-soluble sizing agent dissolves, and the
filaments unravel and spread.
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Pollutants are adsorbed and microorganisms are fixed on the large surface
area of the CarbonFiber.
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Bio film
( radical sludge)
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Microorganism
(microscope photo)
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● Mechanism of Water Purification
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Swaying of the carbon fibers causes movement
of the water and decompostion of pollutants |
Main rutrients and metabolism products
of microcr gmnisms in microbial film |
Water purification principle
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Decomposition of organic matter |
There are aerobic bacterium (bacteria which likes oxygen) and an
anaerobic bacterium (bacteria which likes anoxia). Organic matter is decomposed
into carbon dioxide and water under the aerobic condition by aerobic bacterium,
and organic matter is decomposed into methane, carbon dioxide under the
anoxia by an anaerobic bacterium.
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| Decomposition of organic matter under the condition of aerobic and anaerobic |
Decomposition of organic matter using biological membrane |
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Removal of Nutritive salts (Nitrogen and phosphorus) |
There are denitrification bacteria in microbe group and it decompose
nitrate nitrogen, which is formed by a nitrification reaction, into nitrogen
gas and scatters in the air. In addition, phosphorus is removed from water
because microbes accumulate phosphate ion as polyphosphoric acid. CarbonFiber
elutes iron ion and when iron ion and phosphate ion react, it becomes iron
phosphate. It is insolubilized and fixed.
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| Biological nitrogen removal |
Biological/chemical phosphorus removal |
Attention
Water purification using CarbonFiber depends on the function of bio film
which adheres to fiber as well as adsorption effect of CarbonFiber itself.
It is difficult to have water purification effect in the environment where
bio film is not formed. In addition, in environments where there is no
microbe, in a deficient oxygen state (lack of dissolved O2 DO), or water
without current or movement, it takes a lot of time until the effect is
produced. Therefore, it is important to make microbe environment for a
higher water purification effect. (Measures: oxygen supply, circulation
etc) |
Water Purification Effects
Water quality purification using CarbonFiber is effective in improvement of transparency in a short time, decrease COD and BOD, and purification of TN and TP.
Removal rate of water quality purification using CarbonFiber items（％）
| items |
river |
lake |
sewage |
| biological oxygen demand (BOD) |
50〜70 |
20〜90 |
90〜95 |
| suspended solid (SS) |
50〜70 |
20〜90 |
90〜95 |
| total nitrogen (TN) |
10〜30 |
10〜30 |
30〜70 |
| total phosphorus (TP) |
10〜50 |
30〜90 |
30〜50 |
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CarbonFiber Water Purification Method
With CarbonFiber, a large water purification effect can be obtained simply
by installing the CarbonFibers in water. However, the manner in which this
effect appears differs greatly, depending on site conditions such as the
water area, water depth, amount of water, water flows, water quality, etc.
and the method of installation and amount of CarbonFiber installed. In
cases where higher cost-effectiveness is required in water purification,
the optimum installation plan is necessary.
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