სსიპ - ფერდინანდ თავაძის მეტალურგიისა და მასალათმცოდნეობის ინსტიტუტი
LEPL - FERDINAND TAVADZE METALLURGY AND MATERIALS SCIENCE INSTITUTE
MATERIALS AND COATINGS FOR EXTREME PERFORMANCES: INVESTIGATIONS, APPLICATIONS, ECOLOGICALLY SAFE TECHNOLOGIES FOR THEIR PRODUCTION AND UTILIZATION

SIXTH INTERNATIONAL CONFERENCE

 

«Materials and Coatings for Extreme Performances: Investigations, Applications, Ecologically Safe Technologies for Their Production and Utilization» 

 

September 20-24, 2010 Ponizovka, Crimea, Ukraine

 

RECLAMATION OF INDUSTRIAL WASTE WITH CONTENT OF MANGANESE BY METHOD OF BACTERIAL LEACHING

 

Sakhvadze D.V., Sakhvadze L.I., Jandieri G.V., Rapava A.V., Gigauri R.M., Shukin B.A., Tavadze G.F.

 

Ferdinand Tavadze Institute of Metallurgy and Materials Science,

15, av. Al. Kazbegi, Tbilisi, 0160, Georgia

 Production of manganese in the mining and metallurgical industry is related to the loss of more than 50% of mineral resources as industrial waste. This gives rise to the deterioration of industrial and economic indices as well as to a considerable envi­ron­mental pollution. Especially problematic is the matter of reclamation of dust, slurry and slag formed due to the metallurgical refining process of manganese ore [1,2].

Study of manganese transformation and migration processes under the influence of microorganisms has for an object the solution of practical tasks for the development of efficiet technology of manganese lea­ching from poor ores and waste of the mining and me­tallurgical refining process (dust, slarry, slag etc) [3].

 But the problem of processing of the com­plicated complex manganese-containing Indus­trial waste is for the present on the stage of de­velo­pment.

The object of investigation is manganese-con­taining industrial waste representing a fine disperse powered mass released as a result of gas dry cleaning from the reactivity zone of furnace  (Fig.1,a).

Today in some countries heterotrophic bacteria are used for manganese leaching and as an energetical material – difficult-to-obtain, expensive organic compounds. The worked out technology excludes the use of organic compounds; it is based upon auto­trophic bacteria oxidizing the sulphide minerals up to the sulphate of lower iron oxide.

For the growth of microorganisms the ferrous iron, sulphur and sulphide mineral are used as energetical sources. The optimum temperature of growth of microorganisms makes up 28oC when pH of medium is 2,3 – 2,8.

Strains have been extracted from geothermal waters of the city of Tbilisi. The strains Th. Fer­ro­oxidans extracted from the source N5 showed a great activity. 

Sulphuric acid and products of metabolism of bac­teria – oxalic acid are formed during the process of leaching. They dissolve manganese oxides. The pre­sence of sulphuric acid in the solution ensures the dissolution of manganese carbonates.

After filtering out the products of leaching we get the solution of manganese sulphate in which the concentration of manganese makes up 45 gr/l. These solutions are suitable for the electrolythic extraction of ferrous manganese and electrolythic dioxide of manganese.

It is also possible to get the monohydrate of man­ga­nese sulphate from the solution (Fig.1,b)

 

 

 

 

 

 

 

 

 

 

Fig.1.  a) initial material  (dust);  b) manganese sulphate

 

As a result of purely biochemical activity of bacteria, the extraction of manganese in 10 twenty-four hours reaches 94%  and in 12 twenty-four hours – 98%.

References:

1. Karavaiko G.I., Kuznetsov S.I., Golomzik A.I. The role of microorganisms in leaching of metals from ores, M. Nauka, 1972. (in Russia)

2. Polkin S.I., Adamov E.V., Panin V.V., Tech­no­logy of bacterial leaching of non-ferrous and rare-earth metals, M. Nedra, 1982. (in Russia)

3. Sakhvadze D.V., Sakhvadze L.I., Jandieri G.V., Ta­­vadze G.F., Rapava A.V. Bacterial leaching of  man­ganese from technogennic waste in the mining and metallurgical industry of Georgia, Works of the Institute of Microbiology, Academy of Sciences of Azerbaidjan, Baku, 2009, pp. 299-303. (in Russia)

7-05-2011    ნანახია: 1 427-ჯერ