Method and device for intermittently removing heavy metals in wastewater

Abstract

The invention discloses a method and a device for intermittently removing heavy metals in wastewater. The method comprises the following steps: a) contacting heavy metal-containing wastewater with an adsorbent, and adsorbing to obtain a solid-liquid mixture; b) carrying out plate frame filtration on the solid-liquid mixture to realize solid-liquid separation to obtain filtrate and a filtering cake containing heavy metals; and c) monitoring the concentration of heavy metals in the filtrate, and directly discharging the filtrate if the concentration of the heavy metals in the filtrate meets a preset standard; and if the heavy metal concentration in the filtrate does not meet the preset standard, repeating the step a) until the heavy metal concentration in the filtrate meets the preset standard. According to the method, through the intermittent circulation process of adsorption, filtration, detection and discharge/readsorption, the universality of the adsorbent is perfectly solved by skillfully applying the plate-and-frame filtering, so that the method can be widely applied to the field of removal of heavy metals in industrial wastewater.

Description

technical field [0001] The application relates to a method and a device for intermittently removing heavy metals in wastewater, which belong to the technical field of wastewater treatment. Background technique [0002] In recent years, with the continuous development of my country's industry and economy, the discharge of heavy metal-containing wastewater in the production process has gradually increased, and heavy metal pollution has become one of the main pollution problems of my country's water pollution. Heavy metal pollutants cannot be biodegraded, and they are also highly toxic at low concentrations. Under the action of microorganisms, they will even be transformed into other more toxic valence states. Heavy metal wastewater will not only cause harm to aquatic plants and animals, but also have a bad impact on human health. [0003] Common treatment methods for wastewater containing heavy metals include biological methods, physical methods, physicochemical methods, and ...

AI Technical Summary

Problems solved by technology

However, the current existing methods have various deficiencies and areas to be improved. For example, the ion exchange resin method with the best effect is not only expensive for the resin, but also requires high equipment requirements, and the cost of construction and maintenance is also extremely high.

Some powdery adsorbents such as bentonite, due to their high suspensibility in water, are not easy to precipitate after the adsorption is completed, so solid-liquid separation has become a problem; most of the existing methods will have a solid-liquid separation step, and will There are fixed requirements for the materials used, such as the need for shaped adsorbents, certain mechanical strength, fixed particle size, etc.

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