Suspension liquid-state iron-containing composite reagent as well as preparation method thereof and method for efficiently removing selenate in water

Abstract

The invention discloses a suspension liquid-state iron-containing composite reagent as well as a preparation method thereof and a method for efficiently removing selenate in water and belongs to the technical field of water treatment. The method for efficiently removing selenate in water comprises the following three steps: step one, preparing the suspension liquid-state iron-containing composite reagent from zero-valence iron powder, water, hydrogen peroxide and hydrochloric acid; step two, removing selenate by using the suspension liquid-state iron-containing composite reagent, and integrally adding the prepared suspension liquid-state iron-containing composite reagent containing a solid phase, a colloidal phase and a liquid phase into selenate-containing water to be treated; and step three, carrying out solid-liquid separation. The suspension liquid-state iron-containing composite reagent has the advantages that the iron-containing composite reagent is simple to prepare and low in cost of raw materials, the iron-containing composite reagent contains a plurality of reduction active components, the removal of selenic acid through a reduction method is facilitated, and the iron-containing composite reagent is rich in colloidal phase and high in efficiency of transferring mass with solution, has both adsorption and flocculation effects, is capable of efficiently removing selenate, can still efficiently operate in the co-presence of anions such as high-concentration sulfate radicals and the like, is especially applicable to high-salt selenium-containing wastewater, is environmental-friendly, and is free of secondary pollution.

Description

technical field [0001] The invention belongs to the technical field of water treatment, and more specifically relates to a suspended liquid iron-containing composite reagent, a preparation method thereof and a method for efficiently removing selenate in water. Background technique [0002] Selenium is an essential trace element for the human body and participates in various life activities of the human body. On the other hand, excessive selenium intake by the human body can lead to acute or chronic poisoning. Because the safety range between the physiologically required intake dose of selenium and the toxic dose is too narrow, the human body is easily poisoned by excessive intake of selenium. Water is an important source of selenium intake for humans, animals and plants. In my country's current comprehensive sewage discharge standards, the first, second, and third-level selenium discharge standards are 0.1, 0.2, and 0.5 mg / L, respectively. The limit value of selenium in surf...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the existing selenate removal methods in water, there are cumbersome operations, low cleaning efficiency, and low efficiency under high-salt conditions, especially when high-concentration sulfate coexists. One of the purposes of the present invention is to provide a suspension liquid Iron-containing compound reagent, prepared by hydrogen peroxide solution and zero-valent iron powder, including solid phase, liquid phase and colloidal phase, contains a variety of reducing active components, such as new ecological ferrous substances, structural ferrous substances , ferroferric oxide, etc., can effectively improve the electron transfer efficiency, promote the removal of selenate through the reduction pathway, and can synergistically play the role of adsorption, reduction, flocculation, co-precipitation, nano-effect, etc. to quickly and efficiently remove selenate in water