Recovery and comprehensive utilization method of heavy metals in stainless steel pickling wastewater sludge

Abstract

The invention relates to a recovery and comprehensive utilization method of heavy metals in stainless steel pickling wastewater sludge and discloses a method for recovering and recycling nickel and chrome in sludge generated during the treatment process of stainless wastewater. The method comprises the following steps: leading waste liquid during the pickling process to be directly used for leaching metal ions in the sludge to save the consumption of reagents; adding a certain quantity of acid or alkali in each reaction tank through arranging a plurality of reaction tanks; controlling a pH value; effectively separating various matters according to different solubility of inorganic compounds; researching and developing a recycling technology of the heavy metals in the stainless steel industrial sludge, wherein the recovery efficiency of the heavy metals like the chrome and the nickel is high; leading the recovered heavy metals to be used for smelting stainless steel; leading recovered iron to be used for preparing an efficient flocculating agent; and leading the flocculating agent to be used for sewage treatment to realize sewage reuse and save the treatment cost. The invention has the advantages of simple process and easy operation, as well as popularization and application.

Description

technical field [0001] The invention is applicable to the field of heavy metal recovery and utilization in the stainless steel production, electroplating industry and related surface treatment industrial wastewater treatment sludge, and particularly relates to the recovery and recycling of heavy metals in the stainless steel field. Background technique [0002] With the development of the stainless steel industry, the impact of heavy metal-containing wastewater and solid waste generated during its production and processing on the surrounding soil and surface water environment has become increasingly apparent. The stainless steel industry is an industry that consumes a lot of resources and pollutes heavily. On the one hand, with the development of industry, it consumes a lot of heavy metals, resulting in a relative lack of heavy metal resources; waste water. Heavy metal sludge is the neutralized solid waste of stainless steel and other processing industries. It contains a va...

AI Technical Summary

Problems solved by technology

[0003] The heavy metal sludge has finer particles and is in the form of fine mud; the composition is complex and contains a variety of heavy metal elements such as nickel, zinc, chromium, etc.; metals mostly exist in the states of hydroxides, oxides, carbonates, etc., and the metal content fluctuates within the range of Therefore, it increases the difficulty of comprehensive utilization of heavy metal sludge in wastewater

If the sludge is piled up or directly landfilled without treatment, it will cause secondary pollution to groundwater and the ecological environment, and may be transformed into more toxic compounds under the action of the external environment. Heavy metals will enter the human body, causing varying degrees of poisoning, and ultimately endangering human health

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