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SIPHON washing machine


SIPHON TANK realized compatibility between
“considerations to the global environment” and “cost reduction.”

Replacement of filter media is not necessary.
Maintenance cost can be dramatically reduced.
It contributes to achievement of zero emission, solution to environmental problems,
and response to ISO14000.

The filtration system is used for small water treatment system or by private companies. The filter media are replaced every six months to five years. Although these used filter media can be recycled if they are washed and rehabilitated. However, they are usually disposed of as industrial waste due to such problems as space for installing a washing system and costs for washing filter media. Therefore, we developed the “SIPHON TANK,” which is a filtration system that can produce filtered water of stable quality without replacement of filter media. Since filter media are always kept clean, there is no need to dispose used filter media as industrial waste, an improvement from in the past. It serves as a stepping stone to a solution to environmental problems and achievement of zero emission advocated by ISO14000. It is also expected to significantly reduce maintenance costs, including the cost for replacement of filter media and the cost for backwashing.



Replacement of filter media is not necessary anymore.
The combination of SIPHON WASHING system which is kneading washing among filter media particles and backwashing keeps filter media always clean in the tank. Therefore, periodical filter media replacement is not necessary.
Since filter media are always kept clean, consistent water quality can be achieved.
SIPHON TANKs can keep filter media as same as the condition of new sand. Therefore, consistent filtration is possible. In addition, since SIPHON TANKs have a structure that prevents unevenness of supporting gravel. Therefore, the problems due to unevenness including short pass do not occur. The amount of filter media flowing out due to sludge deposit is also reduced and the capacity to capture suspended substances does not deteriorate.
Maintenance cost is dramatically reduced.
“Cost for filter media replacement work,” “cost for disposing of used filter media as industrial waste,” and “cost for purchasing new filter media for replacement work” are not necessary. Therefore, maintenance costs can be dramatically reduced.
The amount of backwash water can be significantly reduced.
Since SIPHON TANKs exfoliate hard adhering suspended substances by SIPHON WASHING and conduct backwashing only for rinsing the suspended substances away, the amount of backwash water volume can be significantly reduced in comparison with the conventional filtration systems.
5)  SIPHON TANKs serve as a large stepping stone to the achievement of Zero Emission.
Filter media can be used semi-permanently. Therefore, there is no need to dispose of used filter media as industrial waste anymore. SIPHON TANKs are “eco-friendly” filtration systems that significantly contribute as a solution to environmental problems and response to ISO14000.
6)  Water quality as maintenance cost can be significantly reduced.
Suspended substances never accumulate in filter media. The accumulation of suspended substances due to longtime use and the fixation of filter media to each other due to organic matters, etc. can be prevented. Therefore, water quality is always stable, so that risks necessary to maintain water quality can be alleviated. As a result, the costs for water quality analysis or analysis of the status of filter media can be significantly reduced.
7)  Fixation of filter media is prevented.
Since fixation of filter media is prevented, SIPHON TANKs can be used not only for water supply but also for sewage/wastewater treatment.
8)  SIPHON TANKs reduce work load in the following facilities.
Treated water by SIPHON TANK is stabilized so that the burden on the subsequent membrane system can be reduced and extended its life.
9)  Maintenance of SIPHON TANKs is easy.
Cartridge-type screws are used for SIPHON TANKs. Therefore, the maintenance work is easy.
10)  SUS304 is used for the wetted part.
For the wetted part, SUS304 is used under the standard specifications. Since Steal Strength (SS) coated with epoxy tar, etc. is used for filtration systems in general, the significant cost and time is necessary for curing. However, such mending of coating is not necessary for SIPHON TANKs..

SIPHON washing

The Introduction of Siphon Cleaning to the filtration system

Since the principle of Siphon Cleaning was introduced to the filtration system and was systematized, filter media is always kept clean. Therefore, filter media replacement work is not necessary. Filter media is washed by Siphon Cleaning, and backwashing is conducted only for rinsing, so maintenance costs, including the cost for backwash water, can be largely reduced.

The unevenness of supporting gravel is prevented by the unevenness preventing plate.
 Sand washing system creates two kinds of vortexes such as vertical and horizontal vortices that cause sand particles to knead each other in a three-dimensional washing action. The vertical vortex is created in each sand particle by gravity and scooping up force. The horizontal vortex is created in each particle by centrifugal and returning force after hitting the side of inner cylinder. These vortices make sand particles to knead and rub each other in a three-dimensional (3D) washing action.

◆ High cleaning effect

Backwashing and air-washing can only prevent clogging at best. However, by “Siphon Cleaning,” even stubborn sludge can be removed because filter media wash each other with a kneading action. Therefore, filter media can be cleaned up to the degree of turbidity comparable to that of new sand (JWWA A-103).

◆ Filter media cannot be crushed washing by "kneading method” that has optimum cleaning effect.

Due to filter media washing each other using a kneading action, filter media will not be crushed while only sludge attached to the surface is removed. Therefore, filter media can be kept in the condition close to that of new filter media.

◆ The outflow of exfoliated sludge can be avoided or significantly reduced.

Due to the vigorous cleaning effect, the outflow of exfoliated sludge into filtered water can be avoided or significantly reduced, and a constant and consistent water quality can be achieved.

◆ The outflow of filter media is significantly reduced.

Filter media run off during backwashing has a low specific gravity, and extremely large amount of sludge and manganese are attached to it. The run off occurs regardless of particle sizes. Siphon Tanks can significantly reduce the outflow of filter media by keeping filter media in the same condition as new filter media.


   As with conventional filtration systems, filtration is conducted by downflow with pressure. Although the inner cylinder and the screw are placed at the center, filter media are also packed into this area. Filtration is thus conducted by the entire filtration system. A Siphon Tank can treat the same amount of water as conventional filtration systems of the same size.
   Backwashing is first conducted for a short period of time to fluidize filter media, and then Siphon Cleaning is conducted.
Filter media are washed each other by a kneading action in a three-dimensional washing action by the rotation of the screw.
   After SIPHON WASHING, backwashing is conducted to rinse the sludge away. The sludge is completely exfoliated from filter media by SIPHON WASHING. Therefore, the sludge can be easily removed by rinsing.  
*When backwashing is conducted, the muti-layer of filter media by anthracite is also possible.

Example Flow Sheet of a SIPHONE TANK

Line up

Standard Specifications of SIPHON TANKs

 Material Body : SUS304 / Motor bearer・legs : SS400  
 Types Body diameter
Cartridge diameter
Amount of treated water
(m3/H)     *LV=10 
ST-700 Φ700 Φ200 3.7 3.8
ST-900 Φ900 6.3
ST-1000 Φ1000 Φ250 5.5 7.8
ST-1200 Φ1200 11.3
ST-1500 Φ1500 Φ400 7.5 17.6
ST-1600 Φ1600 20.0
ST-1800 Φ1800 25.4
ST-2000 Φ2000 Φ500 11.0 31.4
ST-2200 Φ2200 37.9
ST-2500 Φ2500 Φ700 18.5 49.0
ST-2800 Φ2800 61.5
ST-3000 Φ3000 70.6


 Public sector
 Water Purification Plant in HITACHI City
 Drinking Water supply
 17.6CBM/hr (410CBM/day)
 Water Purification Plant in AOMORI City
 Drinking Water supply
 4.3CBM/hr (100CBM/day)
 Water Purification Plant in GERO City
 6.3CBM/hr (150CBM/day)
 Private sector
 SONY Corporation
 ST-2200 x 2units
 Industrial process water treatment
 Chemical Company
 Industrial process water treatment
 YAZAKI Corporation
 Plating wastewater
 YAZAKI Corporation
 Plating wastewater
 Car Parts Company
 Dissolved-air flotation treated wastewater
 Pretreatment for pure water
 KOREAN Company
 ST-1600x 2units
 Industrial wastewater
 Japanese Copper Factory in Thailand
 Industrial wastewater