Author 1:
Name & Surname: Poperechnikova O. Yu.
Company: RIVS Science and Production Association (Saint-Petersburg, Russia)
Work Position: Head of subdivision
Contacts: e-mail: rivs@rivs.ru

Author 2:
Name & Surname: Sizykh A. S.
Company: RIVS Science and Production Association (Saint-Petersburg, Russia)
Work Position: Engineer–Mineralogist

Author 3:
Name & Surname: Nagaeva S. P.
Company: RIVS Science and Production Association (Saint-Petersburg, Russia)
Work Position: Mineralogist
Contacts: e-mail: SPN@yandex.ru

Inasmuch as the rich iron ore reserves have been depleted and in view of the strong competition on the world iron ore market, the iron concentrate quality requirements are continuously increasing at the present time. As of today, the commonly used technology to raise iron content of magnetite concentrate is regrinding and low-intensity wet magnetic separation. This technology yields minimum increase in the iron content, consumes much energy and expands specific area of the concentrates, which results in higher moisture content of the filter cake and complicates pelletizing. Flotation aftertreatment of iron ore concentrates is a more efficient method of ore processing as it reduces the content of silica, phosphorus, sulfur and other impurities and enables handling the problem of super-concentrate production. In choosing reagent conditions, material constitution of a concentrate to be produced is of importance. Ores at different deposits have different mineral compositions, and there is now way to recommend a universal regime and reagent conditions for reverse cation flotation of magnetite concentrates. Specific difficulty is caused by amphiboles and pyroxenes that are poorly extracted using the existing reagent conditions. The analysis of magnetite concentrates of Poltavsky Mining-and-Processing Integrated Works (Ukraine) showed appreciable quantity of aluminum silicates (mica and amphiboles) and carbonates aside from quartz (mainly as intergrown pieces). For this reason, production of high quality magnetite concentrates at iron content of 69–70 % and recovery of over 92 % in aftertreatment circuit is only possible with new effective reagent conditions which are yet not actualized industrially. In the last 10 years, RIVS has accomplished a great amount of investigation aimed at improvement of iron ore dressing equipment and technology (Russia, Ukraine, Philippines). The flotation aftertreatment technology has been developed as the result; it allows production of iron concentrates with the increase iron content up to 69.5 % at the recovery of 94.6 %.