CN-122010267-A - Heavy metal wastewater treatment method

Abstract

The application provides a treatment method of heavy metal wastewater, and belongs to the technical field of wastewater treatment. The method comprises the steps of adding a calcium silicate material into wastewater containing heavy metal ions, introducing gas containing CO 2 to obtain a mixture, and carrying out solid-liquid separation on the mixture to obtain a purified liquid and a precipitate. According to the application, a calcium silicate material with high carbon mineralization activity is used as a main raw material, CO 2 gas is introduced into heavy metal wastewater to induce a carbon mineralization reaction of calcium silicate minerals, so that heavy metal ions are dissolved in a main product (calcium carbonate) of the carbon mineralization reaction, and the purposes of removing heavy metal ions in the wastewater and solidifying the heavy metal ions are achieved. Compared with the prior art, the method is simple and efficient, can realize high-efficiency solidification of heavy metal ions under the condition of extremely low pH, has extremely low heavy metal dissolution risk, and realizes CO 2 CO-treatment.

Inventors

• WANG FAZHOU
• HUANG KAIYUN
• LIU ZHICHAO

Assignees

• 武汉理工大学

Dates

Publication Date

20260512

Application Date

20260209

Claims (10)

1. 1. The treatment method of the heavy metal wastewater is characterized by comprising the following steps of: adding a calcium silicate material into wastewater containing heavy metal ions, and introducing gas containing CO 2 to obtain a mixture; and (3) carrying out solid-liquid separation on the mixture to obtain a purified liquid and a precipitate.
2. 2. The method according to claim 1, wherein the calcium silicate material includes at least one of γ -dicalcium silicate, β -dicalcium silicate, tricalcium silicate, monocalcium silicate, and industrial waste slag containing a calcium silicate ore phase, and the mass percentage of the calcium silicate ore phase in the industrial waste slag is 60% or more.
3. 3. The treatment method according to claim 1, wherein 1-10 g of the calcium silicate material is added per 100mL of the wastewater.
4. 4. The process of claim 1, wherein the CO 2 -containing gas is introduced for a period of time greater than or equal to 1 hour.
5. 5. The method according to claim 1, wherein the volume percentage of CO 2 in the CO 2 -containing gas is 40-95%.
6. 6. The method according to claim 1, wherein the gas flow rate of the CO 2 -containing gas is 150 to 500lpm.
7. 7. The method according to claim 1, wherein the pH of the wastewater is 0.5 to 7.
8. 8. The treatment method according to claim 7, wherein the concentration of the heavy metal ions in the wastewater is 100 to 3000mg/L.
9. 9. The method of claim 1, wherein the heavy metal ions comprise at least one of Pb 2+ 、Cd 2+ 、Cu 2+ 、Ni 2+ 、Fe 3+ 、As 3+ .
10. 10. The method according to claim 1, wherein after the step of solid-liquid separating the mixture to obtain a purified liquid and a precipitate, the precipitate is recycled after being compression molded.

Description

Heavy metal wastewater treatment method Technical Field The invention relates to the technical field of wastewater treatment, in particular to a treatment method of heavy metal wastewater. Background A large amount of wastewater is generated in the processes of mining, lithium battery production and the like, and mainly contains heavy metal ions such as Pb 2+、Cd2+、Cu2+、Ni2+、Fe3+、As3+ and the like, has high acidity, and is extremely easy to pollute and destroy the ecological environment if the wastewater is not treated. However, conventional heavy metal solidification techniques (e.g., membrane adsorption, electrochemistry, physical adsorption, etc.) generally fail or drastically degrade in performance in strongly acidic environments, resulting in poor treatment of the above-described high acidity wastewater. Disclosure of Invention In view of the technical problems in the background art, the application provides a treatment method of heavy metal wastewater, and aims to provide a wastewater treatment method with good treatment effect on high-acidity wastewater. The embodiment of the application provides a treatment method of heavy metal wastewater, which comprises the following steps: adding a calcium silicate material into wastewater containing heavy metal ions, and introducing gas containing CO 2 to obtain a mixture; and (3) carrying out solid-liquid separation on the mixture to obtain a purified liquid and a precipitate. Optionally, in some embodiments, the calcium silicate material comprises at least one of gamma-dicalcium silicate, beta-dicalcium silicate, tricalcium silicate, monocalcium silicate, and industrial waste containing a calcium silicate mineral phase, and the mass percentage of the calcium silicate mineral phase in the industrial waste is greater than or equal to 60%. Optionally, in some embodiments, 1-10 g of the calcium silicate material is added for every 100mL of the wastewater. Optionally, in some embodiments, the CO 2 -containing gas is introduced for a time greater than or equal to 1h. Optionally, in some embodiments, the volume percentage of CO 2 in the gas containing CO 2 is 40-95%. Optionally, in some embodiments, the gas flow rate of the gas containing CO 2 is 150-500 lpm. Optionally, in some embodiments, the pH of the wastewater is 0.5-7. Optionally, in some embodiments, the concentration of the heavy metal ions in the wastewater is 100-3000 mg/L. Optionally, in some embodiments, the heavy metal ion comprises at least one of Pb 2+、Cd2+、Cu2+、Ni2+、Fe3+、As3+. Optionally, in some embodiments, after the step of solid-liquid separating the mixture to obtain a purified liquid and a precipitate, the method further comprises recycling the precipitate after compression molding. The technical scheme provided by the application has the following beneficial effects: according to the technical scheme, the calcium silicate material with high carbon mineralization activity is adopted as a main raw material, CO 2 gas is introduced into heavy metal wastewater to induce the carbon mineralization reaction of calcium silicate minerals, so that heavy metal ions are dissolved in a main product (calcium carbonate) of the carbon mineralization reaction, and the purposes of removing the heavy metal ions in the wastewater and solidifying the heavy metal ions are achieved. Compared with the prior art, the method is simple and efficient, can realize high-efficiency solidification of heavy metal ions under the condition of extremely low pH, has extremely low heavy metal dissolution risk, and realizes CO 2 CO-treatment. The foregoing description of the application is merely an overview of the present application, and is intended to provide a better understanding of the technical means of the application, as well as to provide a better understanding of the application with reference to the following detailed description of the application, in order to make it possible to provide the above and other objects, features and advantages of the application. Drawings In order to more clearly illustrate the technical solution of the present application, the following description will briefly explain the drawings used in the present application. It is apparent that the drawings described below are only some embodiments of the present application, and that other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art. Fig. 1 is a schematic flow chart of a treatment method of heavy metal wastewater according to an embodiment of the application. Detailed Description Embodiments of the technical scheme of the present application will be described in detail below. The following examples are only for more clearly illustrating the technical aspects of the present application, and thus are merely examples, and are not intended to limit the scope of the present application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as comm