METHOD OF PREPARATION OF GALVANIC SLUDGE FOR ITS UTILIZATION Russian patent published in 2018 - IPC C22B7/00 

FIELD: technological processes.

SUBSTANCE: invention relates to the preparation of galvanic sludge – hydroxides of heavy metals, which are formed during the purification of waste waters of galvanic areas, for their subsequent disposal. Galvanic sludge is mixed in the reactor with a reducing agent of oxidized metals. Prior to mixing, dewatering of galvanic sludge is carried out on vacuum filters or filter presses. It is stirred at the normal temperature for 20–25 minutes. As the reducing agent waste of technical carbon is used, which is introduced in the preparation of galvanic sludge in the amount of 15–100 % of the dry matter of galvanic sludge. At the same time, 80–100 % of the dehydrated galvanic sludge is fed to the reactor before loading of carbon black waste, and the carbon black waste during the mixing time is introduced in three parts – immediately after the loading of carbon black, 5–10 minutes from the beginning of mixing and then after 5–10 min at the stopped agitator.

EFFECT: method provides for the reduction of oxidized metals and their recovery for reuse.

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