Failed to register as Favorite Page
Failed to cancel as Favorite Page
This page is already registered as a Favorite Page
You can't add your company to your favorites.

Latest update: 21/04/2021 13:32:12


WATER PLANet PROJECT: Aiming for an abundant future where everyone can receive the bounty of water

Since the founding of our company in 1939, Nihon Genryo have supported Japanese waterworks from the ground up as a leading manufacturer of filtration media for waterworks over a long period of time. We boast the leading share for filtration media, with our materials currently used by more than 80% of the water purification plants in Japan. In addition, using the technology and foresight that we have cultivated during our long history and our flexible ideas, we developed the “Siphon Series” of water treatment systems that do not require filter replacement. Our products are highly regarded for their excellent mobility, being used for small- to medium-scale waterworks both inside and outside Japan, high-functional water treatment at plants, and for supporting disaster recovery.


Sales Pitch

Chiffon series
Chiffon cleaning
At Japanese water purification plants, recycling work is performed to clean and reuse filtration media that are used and soiled in the filter. Previously, soiled filtration media were all treated as industrial waste, however, from the 1960s, we advocated the recycling and reuse of filtration media from the viewpoint of there being limited mineral resources on earth, and have worked on technological innovations for cleaning sand, which was carried out in Japan for the first time. However, due to deterioration in the quality of raw water in our waterways due to environmental contamination in recent years, there has been an increasing load of filtration media, with the progression of soiling and more severe contamination, therefore, it has become necessary to come up with new innovations in cleaning technology for filtration media. Siphon-style cleaning by rubbing was developed after getting a hint from the formation process of squeaking sand as a result of various trial and error and repeated experiments. We developed a cleaning method that separates and cleans not only attached matter but also soil from adherents, without breaking down the grain diameter of the sand, and have been able to restore soiled sand to make it just like new. We are licensed to use our technology in 33 countries around the world, and the technology is unique to Japan and has won awards such as the National Invention Award and the MEXT Science and Technology Award.
The basic principle of siphon cleaning is washing by rubbing grains of sand together. A batch processing system is used, with the interior having a two-layered structure in which sand is washed by rubbing in the inner cylinder and outer cylinder sections respectively and circulated. Through rotation of the screw installed in the inner cylinder section, two opposing forces are generated by force and gravity that work to push water and filtered sand from the bottom to the top. This results in the filtered material attempting to flow toward the bottom while being scooped up from the bottom to the top, forming a vertical vortex while rolling above the screw. In addition, the filtered sand that is being pushed outward by the centrifugal force caused by rotation of the screw is blocked by the inner cylinder section and pushed back inward, generating a horizontal vortex. With these two vortices, 3D washing by rubbing is performed.
1. Because the material is separated from adherents, cleaning is possible up to a cleaning turbidity value at or under 30 NTU (JWWA A103 standard) to make the equivalent of new sand.
2. The effective diameter and uniformity coefficient can be worked out without breaking down the grain diameter, with excess sludge and manganese layers removed to leave only the ideal manganese layers.
3. Helps toward maintaining a turbidity of 0.1 NTU for filtered water as prescribed by the Ministry of Health, Labor and Welfare as a guideline for preventing Cryptosporidium.
4. It is possible to avoid/minimize reduction of sludge separation.
5. The separation of attached matter/adherents restores the specific gravity of the sand to its original level, minimizing the outward flow of the sand owing to counter-current cleaning.
6. Cleaning and reusing discharged sand significantly reduces waste matter.
High Performance Filter 0.6 Interceptor and Zebra Layer
Compared with standard filtered sand, the high-performance filtered sand 0.6 interceptor has a high suspended substance catch volume, higher filtration efficiency, and higher cleaning effect for counter-current cleaning. The 0.6 interceptor resolves various issues that could not be resolved with conventional filtered sand.
1. The suspended substance catch volume is extremely high.
As a uniform gap is maintained in the vicinity of the middle and lower filtration layers, the suspended substance catch zone is wide, therefore filtration is deep, and in the case of pressure filtration, the suspended substance catch volume per square meter is 2.3 times that found with conventional filtered sand of 0.6–1.3 mm or less.
2. The quality of the treated water is stable.
The rate of expansion of cleaning is approximately 5% higher and cleaning efficiency is also higher, and the amount of residual suspended substances is extremely low. It is difficult for filtration blockage to occur at the surface layer, and for leakage to occur at the lower layer, which makes treatment quality stable.
3. Running costs are significantly lower
The water will be kept clean for a longer period of time, and it is possible to delay the time until the counter-current cleaning cycle or recycling work. This significantly reduces the costs associated with maintenance management.
4. Consideration for the environment
The frequency of counter-current cleaning is reduced, so a reduction in countercurrent water is expected. By being able to reduce industrial waste, the specific gravity due to suspended substances is reduced, also enabling reduction of the outflow of filtration media, and greatly contributing to reduction of CO2.

High performance anthracite: Zebra Layers
In current multilayer filtering, the boundaries of the multiple layers are cleanly stratified after counter-current cleaning, and the suspended substances are only caught by the anthracite surface layer and the boundary between anthracite and filtered sand, with the middle anthracite layer hardly functioning at all. To increase the suspended substance catch volume, we developed “Zebra Layers,” which forms layers of anthracite and filtered sand in stripes like those of a zebra. Furthermore, in combination with a 0.6 interceptor, even higher turbidity catching is realized.
1. Suspended substances are scattered inside the anthracite layer
The suspended substances concentrated on the boundary line between the anthracite and filtered sand are scattered and can be caught inside the anthracite layer.
2. Increased suspended substance catch volume
By changing the Zebra Layers, the suspended catch volume can be increased by 1.78-2.67 times for pressure filtration and 1.2-2.13 times for gravity filtration.
3. Reduce cost of water cleaned by counter-current
A large amount of suspended substances can be discharged in a short time in the cleaning wastewater turbidity. In addition, the counter-current cleaning frequency can be reduced due to the high catch capacity, so we can expect to make the wastewater treatment equipment smaller and reduce CO2.
4. Improved treatment capability by simply replacing the filtration media
The suspended substance catch volume is high; therefore, the treatment capacity is improved by simply changing the configuration from the existing single-layer filtered sand equipment to a multilayer configuration. In addition, by making changes to the equipment, we can expect cost reductions.

A synergy of high-performance filtration media and siphon cleaning
Using the high cleaning capability of siphon cleaning for high-turbidity raw water caught using deep layer filtration, the filtration media can always be kept in a clean state.

Direct filtration method
The 0.6 interceptor and Zebra Layers enable direct filtration even with high-turbidity raw water. If coagulation settlement is not required for preprocessing, the facilities can be placed even in a small area.
Chiffon tank series
Siphon tank(ST)
The filtration media in filtration equipment that is used by small-scale simple waterworks or private companies are replaced every half-year to five years.Although this used filtration media can be reused after cleaning and regeneration,it had been treated as industrial waste.In contrast,our “Siphon tank” filtration equipment was developed so as to be able to always obtain the highest quality filtered water without having to replace the filtration media.The filtration media is always kept clean,and it is no longer necessary to treat used filtration media as industrial waste,which is a large stepping stone toward addressing environmental issues and achieving the zero emissions advocated by ISO14000,and in addition,can be expected to significantly reduce maintenance management costs,including costs for filtration media replacement work,and counter-current cleaning costs.
1.Replacement of filtration media is not required
All filtration media inside the filtration equipment is kept in a state just like new sand by combining siphon cleaning and counter-current cleaning.Therefore, it is no longer necessary for the filtration media to be replaced regularly or at all.
2.Filtration media is always kept in a clean state.
The filtration equipment incorporates siphon cleaning, developed by us,which uses the principle of cleaning by rubbing filtration media together,therefore always keeping the filtration media in a clean state,enabling stable filtration.
3.Counter-current cleaning water volume can be reduced significantly.
As suspended substances that are firmly adhered are fully separated using siphon cleaning, and counter-current cleaning is performed at the end with the sole purpose of rinsing out the suspended substances,the water volume required for counter-current cleaning is significantly reduced to around 1/2-1/3 of that needed for conventional filtration equipment.As a result,the capacity of the water receiving and draining tanks can be downsized,reducing the counter-current cleaning water volume and cost.
4.Prevents adherence of filtration media.
In conventional filtration equipment,when attempting to treat raw water that is contaminated with highly organic matter such as sewage,the filtration media becomes solid,preventing normal filtration from being maintained.The "ST" can always keep the filtration media in a clean state,preventing adhesion of the filtration media and making it possible to obtain stable water quality.
5.It is also optimal for pretreatment of membranes or activated carbon.
By installing the "ST" for membrane treatment or pretreatment processing of activated carbon, the burden in respect to membrane and activated carbon can be reduced,extending the life of the membrane and activated carbon and lowering the maintenance management costs and workload.It is also supplied as a prefilter for soft water equipment of chemical plants.
Mobile siphon tank(MST)
Our conventional siphon tank was limited to permanent tanks in which the installation space can be secured,such as those found in water purification plants and factories.Accordingly,we developed the "MST",which can be used for a wider range of uses,while making the most of the characteristics of the siphon tank.The unit was made compact;therefore,it can be transported by truck.We have a track record of many installations as a standalone distributed water supply style that is optimal for small-scale water supplies and addresses issues such as reduction of the water supply population,aging facilities,and reduction in technical staff.In addition,by simply changing the conditions,such as the filtration configuration or filtration speed inside the filtration equipment,it can be utilized for securing drinking water at times of emergencies and disasters,and realizes a new form of water supply.Furthermore,the mobile water purification equipment can be utilized widely,including high-turbidity waste water treatment for civil engineering sites.

This company is recommended by the following support organizations.

Kanto Head Office, SMRJ