Novel Environmentally Friendly, Poly Silicate Iron-based Coagulant Developed for Water Treatment by Fuji Pigment; Resulting Sludge Can Be Used As Agricultural Fertilizer

KAWANISHI, Japan, September 16, 2014 /PRNewswire/ — Fuji Pigment Co., Ltd. announced on September 16 that it has developed a new type of coagulant for treatment of drinking water which is friendly to the environment. Unlike the conventional coagulant that is based on poly aluminum chloride (PAC), the poly silicate iron (PSI)-based new product, “FUJI SP PSI,” invented by Dr. Ryohei Mori at Fuji Pigment, is safe for the earth as well as for plant, animal and human health because PSI mainly consists of safe and abundant elements, iron and silicon, both of which also constitute soil and the earth crust. Therefore, sludge caused by FUJI SP PSI can be recycled back to agricultural soil and can be utilized as fertilizer owing to its environmentally friendly nature, offering a new solution for the modern water treatment industry.

In recent years, water is contaminated due to the worldwide human population explosion.

Currently used coagulants for water treatment such as PAC, aluminum sulfate, iron chloride, etc., cannot fulfill the requirements of growing demand today. Furthermore, aluminum-based coagulants have the problematic issue of adversely influencing the environment. When spread onto soil, phosphate could deplete due to the existence of aluminum. In addition, such coagulants may cause central neurological diseases among people because of residual aluminum.


1. Environmentally friendly coagulant for water treatment. Sludge generated by PSI can go back to soil and used as fertilizer. This is the most important feature of FUJI SP PSI. The sludge generated by FUJI SP PSI contains rich phosphor, which is essential nutrition for plant growth and, therefore, can be used as fertilizer for agricultural soil.

2. One weakness of PSI is gelation during storage. However, it is improved by our technology. PSI tends to cause gelation during long-term storage in a container. However, we have succeeded in suppressing gelation with our technology, FUJI SP PSI.

3. The amount of sludge can be decreased. Generally, FUJI SP PSI has a stronger coagulation effect than PAC which enables us to provide strong sludge compression and dehydration. Therefore, the amount of sludge can be lowered.


Dr. Ryohei Mori
Research and Development
Fuji-Pigment Co., Ltd.
Tel: +81-72-759-8501