Integrated process for treating heavy metal wastewater

Abstract

The invention relates to an integrated process for treating heavy metal wastewater. A reactor adopted in the integrated process is simple to construct, compact in structure, high in heavy metal wastewater treatment efficiency, and easy to operate, manage and maintain. The integrated process is free of a nanometer zero-valent iron mixed solution refluxing device, capable of increasing the nanometer zero-valent iron by sufficiently utilizing flow fields, which are formed by a stirring device on the inner part of the reactor, and capable of realizing solid-liquid separation and zero-valent iron refluxing by utilizing the gravity of the nanometer zero-valent iron, so that the nanometer zero-valent iron is sufficiently mixed and circulated in the reactor, and the high-adsorption performance and strong reduction characteristic to the heavy metals are greatly utilized. An integrated device is used to treat simulated wastewater and the pre-treated electroplating wastewater containing heavy metals, so that the concentration of various heavy metals in the treated outlet water are better than the emission standards of the national pollutant I. Moreover, the reactor has short hydraulic retention time and high treatment efficiency, and is free of additionally added chemical coagulant, capable of separating and recycling the nanometer zero-valent iron containing heavy metals and capable of avoiding the secondary pollution of the heavy metals.

Description

technical field [0001] The invention belongs to the technical field of heavy metal wastewater treatment, and in particular relates to an integrated process for treating heavy metal wastewater. Background technique [0002] Heavy metal pollution has the characteristics of refractory, easy to enrich, and difficult to remove. It is not only highly toxic, but also has concealment, irreversibility, and long-term nature. It can accumulate in organisms and amplify the toxicity through the bioaccumulation of the food chain. Therefore, Heavy metal pollution has become one of the most harmful water pollution problems. Heavy metals generally exist in nature in natural concentrations, but due to the increasing mining, smelting, processing and commercial manufacturing activities of heavy metals, heavy metals enter the atmosphere, water and soil. Industrial wastewater containing heavy metals mainly comes from mechanical processing wastewater, mining wastewater, steel and non-ferrous meta...

AI Technical Summary

Problems solved by technology

In addition, the traditional nano-zero-valent iron treatment heavy metal sewage reactor needs to set up a reaction zone and a precipitation zone separately, which not only leads to a large area of ​​the reactor, but also requires a large number of reflux equipment

During the reflux process, due to the mutual support between the nanoparticles increases the required energy consumption, and the bonding of the nanoparticles in the reflux pipeline will block the pipeline, so the unsatisfactory reflux effect will make the nanoparticle in the reaction zone The concentration of zero-valent iron gradually decreases, and the subsequent treatment effect cannot be guaranteed

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