G – Cube
Ammonium nitrogen
Oxidation
Nitrate nitrogen
low reactivity are proliferated in the carrier.
G-Cube (nitrification carrier)
G-Cube is a carrier, in which nitrification
bacteria are entrapped and immobilized,
for the purpose of retention of them. The
shape is a cube with sides of around 3
mm. If the carrier is cultured in the
environment, in which nitrification
bacteria easily proliferate, they
proliferate at the inside of the surface of
carrier.
Anaerobic condition
Nitrogen gas Anaerobic condition
G-Cube
Activated
sludge
Nitrate nitrogen
Nitrite nitrogen
Nitrate
bacteria
Environment, in which nitrification
bacteria easily proliferate
Culture
G-Cube
Separator
Treated wastewater
６
４
２
１００
Bound carrier B
５０
Bound carrier A
０
０
５
１０
１５
２０
２５
３０
１００
２００
Status of
manufacturing
３００
４００
５００
６００
ＢＯＤ concentration （mg/L）
Change of nitrification by BOD Concentration
Nitrification rate of conventional method (suspension type) and G-Cube
After the culture
Comparison of microbes immobilization denitrification system with conventional method
Function of G-Cube
The nitrification bacteria with the function of nitrogen removal are the
bacteria, of which high concentration is relatively difficult to be
retained in the floating sludge in the aerobic tank due to the slow
proliferation rate.
The G-Cube can retain the nitrification bacteria in high concentration,
and becomes possible to treat ammonium nitrogen in a short time
Microbes immobilization
denitrification process
Nitrified circulation fluid
■ Proliferation pattern of microbes (nitrification bacteria)
The reactivity of microbes reaches the peak at around 60 days after
the start of the culture, and they exert enough function.
After that, the microbes existing at the surface layer, which has good
culturing condition, proliferate further and pack densely, then stabilize
with the quantity of microbes that consistent with the environmental
conditions (ammonia concentration and dissolved oxygen
concentration).
G-Cube
Ｂ
Raw water
Raw water
tank
after the addition of designated amount in the aerobic tank.
1) Nitrogen (ammonium nitrogen)
involved in the raw water flowed
in once pass through the
denitrification tank, then flows in
the nitrification tank.
Treated wastewater
Denitrification
tank
Nitrification
tank
2) Ammonium nitrogen is
effectively changed to nitrate
nitrogen by the function of GCube in the nitrification tank. At
the same time, BOD is also
treated by the function of
aerobic bacteria.
Conventional method
（Circulation nitrification
and denitrification process）
Settling tank
Immediately after
the immobilization
Nitrification
bacteria
After 60 days
Nitrification bacteria
Disinfection
tank
3) Treated wastewater in the
nitrification tank (nitrified fluid) is
circulated to the denitrification
tank and the part of it is
transferred to the settling tank.
4) The nitrified fluid circulated to
the denitrification tank reacts
with the BOD in the inflow water
and is vaporized and removed
as nitrogen gas.
2) Double treatment time and tank
capacity are needed compared
with the microbes immobilization
denitrification process due to the
poor nitrification ability, because
the nitrification is performed by
the function of suspended
nitrification bacteria in the tank.
Ｂ
Microbe floc
G-Cube
０
Water temperature（℃）
Denitrification process
Conventional standard activated sludge process cannot remove
much of ammonium nitrogen excluding a part removed by settling,
because the purpose of it is removing of organic matter. Although the
circulation nitrification and denitrification process (anaerobic-aerobic
activated sludge process) was developed as a method to remove
nitrogen, the size of the nitrification tank is around double one of
standard activated sludge process. Because a big capacity of tank is
needed in order to retain the nitrifying bacteria for long time, of which
function is weak due to the slow proliferation. The microbes
immobilization denitrification system makes nitrogen removal
possible even with the almost same tank capacity as the standard
activated sludge process, because a large quantity of nitrifying
bacteria, which hardly proliferate, are entrapped and immobilized in a
carrier.
Pollutant
８
G-Cube
１５０
０
3ｍｍ
Nitrification process
２００
Conventional method (suspension type)
１０
Inside of G-Cube
Nitrification
bacteria
Nitrite
bacteria
2. Easy culturing
3. Less impact from nitrification inhibitory factors
1. High nitrification rate of around double compared with
suspension type (compared with our company’s product)
Discharge into the air
Aerobic condition
Raw
water
a polymer such as polyethylene glycol.
Features of G-Cube
The entrapping immobilization carrier (G-Cube) has the following features
compared with other bound carrier, because the nitrification bacteria with
Nitrification rate（mg-N/ｈ・L－carrier）
Biochemical treatment is currently the mainstream of the method to
remove nitrogen in the wastewater. It is the method that ammonium
nitrogen in the wastewater is finally changed to nitrogen gas using the
activity of microbes.
The process is broadly divided into the following two steps:
(1) In the nitrification process, ammonium nitrogen is oxidized to nitrite
nitrogen or nitrate nitrogen under the aerobic condition. The microbes,
which act at that time, are nitrifying bacteria.
Then,
(2) In the denitrification process, the nitrite nitrogen or nitrate nitrogen is
changed to nitrogen gas by the function of denitrifying bacteria under the
anaerobic condition and discharged into the air.
What is the entrapping immobilization carrier.
The entrapping immobilization carrier (G-Cube) is molded microbes using
Nitrification rate（mgN/L・tank・ｈ）
Principle of nitrogen removal
Ｍ
Raw water
Treated wastewater
After 200 days
Raw
water tank
Denitrification
tank
Nitrification
tank
Settling
tank
Disinfection
tank
LG-Hitachi Water Solutions