METHOD OF PURIFICATION OF THE NATURAL AND INDUSTRIAL WASTE WATERS FROM SULFIDES AND HYDROGEN SULFIDE Russian patent published in 2006 - IPC C02F1/74 B01D37/02 C02F103/02 

FIELD: pulp-and-paper industry; tanning industry; chemical industry; methods of purification of the natural and industrial waste waters from sulfides and hydrogen sulfide.

SUBSTANCE: the invention is pertaining to the field of purification of the natural and industrial waste waters of the various enterprises including pulp-and-paper, tanning, chemical enterprises from sulfides and hydrogen sulfide. The method provides for filtration of the being purified water or the waste waters run-offs through the layer of the grainy loading, which has been preliminary filled with by iron-bearing reactant. At that in the capacity of the iron-bearing reactant they use the iron hydroxide suspension, which is mixed with the pure wash water in the end of purification and using their mixture fill in the main part of the expanded layer of the being washed grainy loading. Then the washing action is completed, and the formed in the loading during the filtration run the iron sulfide is treated with the atmospheric oxygen up to the iron hydroxide. The air is fed in the beginning of the water-air washing through the layer of the grainy loading till oxidation of the main mass o the iron sulfide. After that they feed only the wash water, and the iron hydroxide withdrawn during the purification action is separated from it and again mixed with the pure wash water before the termination of the next washing action of the grainy loading. For increasing of the filter-cycle duration the water subjected to purification before its feeding in the grainy loading is saturated with oxygen and-or it is introduced with the other oxidizing agent. For reduction of the idle time of the filter dealt with oxidation of the iron sulfide formed in the loading during the filter-cycle, together with the air fed through the layer of the loading in the beginning of the was they feed oxygen and-or other gaseous oxidizing agent either introduce then oxidizing agent into the pure wash water before its feeding in the layer of the grainy loading. The presented method reduces the cost value and simplifies the technological process of the purification.

EFFECT: the invention ensures reduction of the cost value and simplification of the technological process of the purification.

4 cl, 1 ex