Resource utilization method for iron sludge

Abstract

The invention discloses a resource utilization method for iron sludge. The resource utilization method comprises the following steps: wet oxidation: pulping and dissolving the iron sludge, and separating to obtain an iron sludge cake after a wet oxidation reaction; acid dissolving: reacting the iron sludge cake through sulfuric acid dissolution to obtain a mixed liquor I; reduction: treating the mixed liquor I through an iron powder reduction method or a gas reduction method to obtain a mixed liquor II, and filtering to obtain a filter liquor and a filter residue; cold crystallization: performing cool crystallization on the filter liquor, and separating to obtain industrial grade FeSO4.7H2O and a ferrous sulfate saturated solution; and preparation of polymerized ferric sulfate: adjusting the pH value of the ferrous sulfate saturated solution to be 1-2, adding an oxidizing agent, and performing a heat preservation stirring reaction at the temperature of 20-30 DEG C for 2-6 h, and concentrating to obtain a polymerized ferrous sulfate solution. According to the resource utilization method for iron sludge provided by the invention, ferrous sulfate and polymerized ferric sulfate are produced by taking the solid waste iron sludge as a raw material, and thus the iron sludge is sufficiently utilized.

Description

technical field [0001] The invention relates to the technical field of industrial waste resource treatment, in particular to a method for resource utilization of iron slime. Background technique [0002] At present, there are mainly two sources of domestic iron sludge: 1. Iron sludge produced during the treatment of wastewater by the Fenton method. Compared with the general chemical oxidation method, the Fenton method has unique advantages in the treatment of refractory organic matter. Therefore, this method is often used in industrial wastewater. However, a certain amount of chemical sludge will be produced in the process of treating wastewater by Fenton method, which will cause great harm to human beings and the environment if not properly treated. 2. From the production of amino compounds, most of which are important pharmaceutical, dye, and pesticide intermediates, such as H acid (1-naphthylamine-8-hydroxy-3,6-disulfonic acid monosodium salt), CLT Acid (2-chloro-5-amin...

AI Technical Summary

Problems solved by technology

Most domestic use iron powder to reduce nitro group to make such compounds. Although this method is simple in process and operation, it will produce a large amount of iron sludge containing organic poisons and difficult to handle.

[0003] A large amount of iron sludge is directly piled up as solid waste, which not only pollutes the environment, but also causes a waste of resources

If the iron slime is not properly treated, it will mainly cause the following hazards: 1. Occupy a large amount of land resources; 2. Under the action of the external environment, the iron slime piled up for a long time will chemically react with the substances in the soil, thereby destroying the soil. structure

3. Iron sludge is directly discharged into rivers, lakes and oceans, which will cause serious pollution of water bodies

4. After a large amount of stacking, the sludge will contain some viral bacteria, which will endanger human health

5. my country is originally a country with a shortage of resources. Iron sludge is directly discharged into the environment without treatment, which will lead to serious waste of land resources and iron resources.

Stockpiling and land burial will not only produce secondary pollution, but also lead to serious waste of resources

Sending iron slime to the iron and steel plant for recycling can reduce land occupation, but the iron slime has a finer particle size, which can easily block the ironmaking furnace, resulting in poor ironmaking operating conditions, lower product quality, and difficulty in recycling

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