A comprehensive recycling method for nitrogen-containing and sulfur-containing iron salt

Abstract

The invention discloses a comprehensive recycling and use method for nitrogenous sulfur-containing ferrite, and belongs to the technical field of secondary resource recycling and reuse. The method comprises the following steps: performing drying denitrification on nitrogenous sulfur-containing ferrite so as to obtain fume with nitric oxide and sulfur-containing ferrite, that is, to separate the nitrogen element from elements of iron and sulfur; recycling the fume with the nitric oxide for preparing nitric acid, performing ammonia leaching on the sulfur-containing ferrite so as to obtain iron ore concentrate and an ammonia leaching solution, that is, to separate sulfate radicals from iron; directly selling the iron ore concentrate, performing steaming crystallization on the ammonia leaching solution so as to obtain ammonium sulfate and condensate water, selling the ammonium sulfate, and recycling the condensate water. The whole recycling process is free of waste residue or wastewater, and harmless and clean treatment on the nitrogenous sulfur-containing ferrite is realized. The method is short in process course, easy in technical condition control and simple to operate, and resource recycling of iron, sulfur and nitrogen in the nitrogenous sulfur-containing ferrite is achieved.

Description

technical field [0001] The invention belongs to the technical field of secondary resource recovery and utilization, in particular to a comprehensive recovery and utilization method of nitrogen-containing and sulfur-containing iron salts. Background technique [0002] The jarosite method is often used for iron removal in traditional nickel electrolytes. This method consumes a lot of iron and alkali, and the obtained jarosite slag contains high value metals, and the valuable metals such as nickel and iron cannot be recycled, resulting in The direct metal recovery rate dropped significantly. In order to reduce the cost of the nickel electrolytic wet iron removal process and increase the direct recovery rate of valuable metals, the traditional process uses the fire method to remove iron to obtain a secondary nickel concentrate containing less than 3% iron, but due to the properties of iron and cobalt Similarly, in the process of removing iron by pyrolysis, a large amount of cob...

AI Technical Summary

Problems solved by technology

[0002] The jarosite method is often used for iron removal in traditional nickel electrolytes. This method consumes a lot of iron and alkali, and the obtained jarosite slag contains high value metals, and the valuable metals such as nickel and iron cannot be recycled, resulting in Significant drop in direct metal recovery

In order to reduce the cost of the nickel electrolytic wet iron removal process and increase the direct recovery rate of valuable metals, the traditional process uses the fire method to remove iron to obtain a secondary nickel concentrate containing less than 3% iron, but due to the properties of iron and cobalt Similarly, in the process of removing iron by pyrolysis, a large amount of cobalt also enters the slag along with the iron, causing the recovery rate of cobalt to plummet

In view of this, the new nickel smelting process uses nitric acid leaching to treat iron-containing nickel-copper sulfides, so that all the iron in the nickel-copper sulfides is leached into the leach solution, and for this leach solution, the iron in the solution is removed by pyrolysis. Converted into nitrogen-containing and sulfur-containing iron salt, which contains Fe 30-50%, SO 4 2- 5-45%, NO 3 - 5-20%, can not be directly exported, if it is stored as solid waste, it will cause serious waste of resources while causing environmental pollution