Technology of Inorganic Flocculant: Polytetsu™

Multifunctional Inorganic Flocculant.

Technology about the water processing agent which responds to various needs in waste water processings, such as phosphate, heavy metals, COD, BOD and supress of generating hydrogen sulfide, not only as a flocculation agent.


Outline of technique

The inorganic flocculation agent which Nittetsu Mining is manufacturing and selling was invented by chance in the process which refining bismuth from copper ore stone using iron ion as catalyst.

At 1970's when this technology was established, sea pollution was occurred by dumping ferrous sulfate which was generated in the process that sulfuric acid is corrected from waste acid.
In the basis of such a time background, our company was succeeded in development of Polytetsu™ used for water treatment and which was made from ferrous sulfate.

Although the iron coagulant agent is generally recognized that corrosive is high, but it is the case of ferric chloride.
The Polytetsu™ have low corrosiveness compared with ferric chloride that keep drainage processing equipment painfulness.
Moreover, since chlorine is not included, it is effective in composting of sewer sludge cake and does not become the cause of dioxin generating if it were incinerated.

Corrosion test
Material Poly ferric sulfate
(30°C x 100h)
Ferric chloride
(30°C x 30h)
sus304 0.0(g/m2/h) 99.4(g/m2/h)
sus316 0.0(g/m2/h) 72.5(g/m2/h)

In processing of sewer sludge, sulfur compounds are generated as bad smells, such as hydrogen sulfide and methylmercaptan.
Moreover, hydrogen sulfide causes corrosion of concrete and metal .So Fe3+ and the Fe2+ ion catches these compounds that work as not only flocculant but also deodorant.

The technology of adding iron or aluminum flocculant to coprecipitate phosphate which is one of the causes of eutrophication is known as general technology.
Polytetsu™ also has the powerful phosphate removal effect, and the outflow of phosphate to discharge water is controlled.

Appearance Reddish brown liquid
Specific gravity(20°C) >1.45
pH(1w/v%) >2
Total Fe(T-Fe) >11.0(w/w)%
Fe2+ <0.07(w/w)%
SO42- 24 - 29(w/w)%
Cl- <0.05(w/w)%
Freeze temperature(°C) -12°C±1°C


Principal ingredients: basic ferric sulfate (common name: poly ferric sulfate)

City sewage, Human excrement, Chemicals, Paper pulp, Food products, Garbage

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