Method and device for separation and recovery of heavy metal ions by membrane-forming mineralization fixation

A film mineralization fixed separation and recovery method for heavy metal ions, including the following steps:

• mixing composite mineral particles with heavy metal acidic wastewater, and carrying out a first hydration reaction under static conditions to form a negatively charged colloidal liquid film rich in Ca(OH)2, using the colloidal liquid film to adsorb, precipitate and crystallize heavy metal ions in the heavy metal acidic wastewater to obtain particles with an outer mineralized film, the particles with the outer mineralized film have a spacing between the mineralized film- and the particles;
• separating the particles with an outer mineralized film to obtain a mineralized film and particles, and then recovering the film and particles separately;
• and
• a preparation method of composite mineral particles includes the following steps:
• mixing at least one of sodium carbonate/sodium silicate with bentonite, carbide slag and water, and carrying out a second hydration reaction, obtaining the composite mineral particles after granulation, aging and dehydration condensation;
• particle sizes of bentonite and carbide slag are independently ≤74 μm;
• bentonite and carbide slag are dried before use;
• drying the bentonite and the carbide slag at 100-110° C. for 2-4 h;
• wherein mixing at least one of the sodium carbonate/sodium silicate with the bentonite, carbide slag and water comprises first, mixing the sodium carbonate/sodium silicate, bentonite and carbide slag evenly obtain a mixture, followed by adding water to the mixture with mixing;
• the particle size of the product obtained by granulation is 2-7 mm.