48 results about "Acid mine drainage" patented technology

The utility model discloses an isolation belt device for blocking and treating acid mine wastewater, and belongs to the technical field of mine wastewater isolation. The device comprises a buoy, an isolation belt fixing frame is arranged at the bottom of the buoy, a weight settling box is arranged at the bottom of the isolation belt fixing frame, and filler is filled in the weight settling box; biomass filler is arranged in the isolation belt fixing frame, and three-dimensional elastic brush filler is arranged on the front side and the rear side of the isolation belt fixing frame in a binding mode. The device disclosed by the utility model is simple in structure, can be effectively assembled according to site conditions, can be in contact with the bottom, realizes multi-depth treatment, can effectively reduce the concentration of dissolved oxygen converged into AMD, gradually improve the bottom layer environment, promote the growth of anaerobic microorganisms, perform biofilm formation synergistic treatment by using indigenous microorganisms and avoid the problem of adaptability of exogenous microbial agents, and can be effective for a long time; the cost and the risk of additionally adding nutrient sources and microorganisms are reduced.

The invention provides an acid mine wastewater comprehensive treatment method, and belongs to the field of mine wastewater treatment.The method treats wastewater through three stages of iron removal pretreatment, replacement copper collection and neutralization treatment in sequence, firstly, the pH value of the wastewater is adjusted in an iron removal reaction tank for reaction, after solid-liquid separation, part of underflow flows back, and the rest enters a filter pressing system; then the liquid subjected to iron removal is guided into a copper recovery reaction tank, copper recovery is conducted through a reducing agent and an iron powder system, and underflow backflow and filter pressing treatment are conducted; and finally, adjusting the pH value of the liquid after copper collection in a neutralization reaction tank, oxidizing, carrying out solid-liquid separation and underflow reflux, and finally discharging after reaching the standard, thereby realizing deep purification of the acid mine wastewater. The slag generated by the method provided by the invention is common industrial solid waste, the environmental risk of waste slag stockpiling is reduced, the reaction efficiency is optimized through underflow reflux in the whole process, and efficient recovery of copper and stable standard treatment of wastewater are realized.

The invention discloses a high-concentration sulfate acid pit water treatment method based on an acid-resistant SRB biological cathode, which comprises the following steps: enabling acid pit water to pass through a grid and then enter a regulating reservoir; introducing the wastewater in the regulating tank into a biological membrane electrochemical device for electrochemical reaction; oxidizing Fe < 2 + > in the wastewater into Fe < 3 + > on a titanium-based IrO2 anode plate and releasing electrons in an anode chamber; in the cathode chamber, an acid-resistant SRB bacterial film loaded on the surface of the carbon felt electrode reduces SO4 < 2-> into S < 2-> by utilizing transferred electrons; cO2 microbubbles are introduced into the liquid in the cathode chamber to react with S < 2-> to generate sulfur precipitates, and the reacted mixed liquid enters a cyclone separator to realize gas-solid separation; and carrying out hydrolysis reaction on Fe < 3 + > in the effluent of the anode chamber to generate Fe (OH) 3 precipitate, mixing the Fe (OH) 3 precipitate with sodium silicate, and calcining to convert the mixture into magnetic alpha-Fe2O3. The method can effectively remove SO4 < 2-> and recover iron sludge.

The application discloses a kind of acid mine wastewater treatment system and processing technology thereof, belong to wastewater treatment technical field, the system includes acid mine wastewater regulating tank, tailings slurry tank, first thickening tank, secondary thickening tank, sludge regeneration tank and sludge thickening tank, acid mine wastewater regulating tank is connected by acid water pump with the water inlet of first thickening tank, tailings slurry tank is connected with the first thickening tank, the water outlet of first thickening tank is connected with secondary thickening tank, the sludge inlet of secondary thickening tank is connected with sludge thickening tank;The sludge inlet of sludge regeneration tank is connected with the sludge discharge port of secondary thickening tank, the sludge discharge port of sludge regeneration tank is connected with the sludge inlet of sludge thickening tank, and waste water treatment is carried out using the system.The application utilizes pyrite beneficiation process tailings slurry cooperates fly ash and active sludge to treat acid mine wastewater, can remove heavy metal simultaneously, realizes acid mine wastewater resource utilization, protects the ecological environment of mining area, reaches the purpose of green production of mine safety.

In one aspect, the disclosure relates to methods for recovering metal compounds from mine waste, wherein the mine waste comprises at least one metal. Also disclosed herein are methods related to recovering metal compounds from acid mine drainage, wherein the acid mine drainage waste comprises at least one metal. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.

The present invention relates to the technical field of governance of abandoned pyrite mining areas, and particularly relates to an ecological anti-seepage structure for waste rock piles in abandoned pyrite mining areas and a construction method thereof, including a passivation layer formed on the surface layer of the waste rock pile body in the abandoned pyrite mining area, a shotcrete layer with wire mesh arranged on the surface of the passivation layer, lattice beams arranged on the surface of the shotcrete layer with wire mesh, and a soil-covered greening layer arranged in the grid space of the lattice beams; fixing network anchor pipes and slope-fixing anchor pipes are arranged in the waste rock pile, the wire mesh of the shotcrete layer with wire mesh is fixed on the waste rock pile slope through the fixing network anchor pipes and the slope-fixing anchor pipes, and the lattice beams are fixed on the waste rock pile slope through the slope-fixing anchor pipes. The present invention can in-situ seal the waste rock pile body in the abandoned pyrite mining area through the passivation layer, the shotcrete layer with wire mesh, the slope-fixing anchor pipes and the lattice beams, greatly reduce pyrite acid mine drainage at the source, and the overall structure has long-term stability and long-term functionality. At the same time, the use of the soil-covered greening layer can better achieve ecological reconstruction.

The application discloses a high-concentration sulfate radical acid mine water treatment method based on acid-resistant SRB biological cathode, which comprises the following steps: after the acid mine water is filtered through a grid, the acid mine water is fed into an adjusting tank; the wastewater in the adjusting tank is fed into a biological membrane electrochemical device to perform an electrochemical reaction; in an anode chamber, Fe 2+ in the wastewater is oxidized into Fe 3+ and releases electrons; in a cathode chamber, the acid-resistant SRB bacterial membrane loaded on the surface of a carbon felt electrode utilizes the transmitted electrons to reduce SO4 2‑ into S 2‑ ; CO2 micro-bubbles are fed into the liquid in the cathode chamber to react with S 2‑ to generate sulfur precipitate, and the mixed solution after the reaction is fed into a cyclone separator to realize gas-solid separation; Fe 3+ in the water in the anode chamber generates Fe(OH)3 precipitate through a hydrolysis reaction, the Fe(OH)3 precipitate is mixed with sodium silicate, and is calcined to be converted into alpha-Fe2O3 with magnetism. The method can effectively remove SO4 2‑ and recover iron mud.

The present application belongs to the technical field of acid mine drainage pollution treatment, and specifically discloses a material for treating acid mine drainage, a preparation method thereof and a wastewater treatment method. The material is a combination of three kinds of natural mineral-based functional materials, which are a first functional material, a slow-release material, mainly a carbonate rock matrix, manganese dioxide and a binder, with a mass ratio of 7-8:1-2:1; a second functional material, a catalytic oxidation material, mainly manganese dioxide, fibrous magnesium-rich clay mineral and a binder, with a mass ratio of 7-8:1-2:1; and a third functional material, a high-performance adsorption material, mainly volcanic clay mineral, manganese dioxide, fibrous magnesium-rich clay mineral and a binder, with a mass ratio of 5-7:1-2:1-2:1; and the mass ratio of the first functional material, the second functional material and the third functional material is 1:10:10. The material provided by the present application is simple to assemble and maintain in the wastewater treatment method, does not need additional chemical agents, avoids sludge blockage and secondary pollution, and has low preparation and treatment costs.

The invention discloses a method for simulating phosphorus and chromium migration during farmland irrigation with acid mine wastewater, which comprises the following steps: mixing a plant-derived organic material with deionized water to obtain a soluble organic matter; h2O2 oxidizes Fe < 2 + > to prepare pure Schwertmannite, and the pure Schwertmannite is placed in a phosphate solution to obtain phosphorus-loaded Schwertmannite; mixing the phosphorus-loaded Schwertmannite and the soluble organic matter with a chromate solution, carrying out oscillation adsorption, carrying out solid-liquid separation after adsorption, carrying out CrO and POconcentration change test on filtrate, and carrying out mineral characterization on separated solids; a three-dimensional fluorescence spectrum is adopted to track composition conversion of the soluble organic matter in the reaction process; and analyzing the component change of the supernate before and after the reaction by adopting Fourier transform ion cyclotron resonance mass spectrometry. The influence mechanism of DOM on phosphorus and chromium fate in mineral / water interface molecular fractionation is disclosed from the molecular level, and a scientific basis is provided for collaborative migration risk assessment of phosphorus and heavy metal in acid mine wastewater irrigation area farmland.

The invention provides a comprehensive collection and treatment method for acid mine wastewater, and relates to the technical field of mines, environmental protection and water treatment. The main comprehensive effect is that a circle of ditch is arranged around the slag, so that the acid wastewater which is generated by the slag and is difficult to collect is discharged into the bottom of the ditch along the terrain, and the problem that the acid wastewater of a mine is difficult to completely collect is solved. Meanwhile, a sewage treatment plant is arranged under the mountain, and pollutants such as copper and cadmium in sewage are treated through processes such as neutralization aeration and coagulating sedimentation. A neutralization tank is additionally arranged behind the sedimentation tank, so that the pH of the sewage is adjusted back to a normal interval, and the sewage can be discharged after being filtered by quartz sand. According to the invention, the function of integrating collection and treatment of the acid mine wastewater can be realized.

The invention discloses a modified red-mud-based arsenic removal agent for acid mine wastewater as well as a preparation method and application of the modified red-mud-based arsenic removal agent. The preparation method of the arsenic removal agent comprises the following steps: placing the red mud in acid mine wastewater for modification reaction, and sequentially carrying out solid-liquid separation, washing and drying to obtain the arsenic removal agent, the mass volume ratio of the red mud to the acid mine wastewater is 1-15g / L; the pH value of the acidic mine wastewater is 1-3, and the concentration of ferric iron is 3-4g / L. According to the arsenic removal agent, red mud serves as a matrix, the arsenic removal capacity of the red mud can be greatly improved only through impregnation modification by means of the synergistic effect between the red mud and acid mine wastewater, and based on the excellent performance of the red mud-based arsenic removal agent, when the red mud-based arsenic removal agent is used for deep arsenic removal of wastewater, the arsenic removal capacity of the red mud can be greatly improved only through adjustment of the pH of a system. According to the present invention, the arsenic ions with different valence states can be completely and deeply removed by using the arsenic removal agent, and the test results show that the removal rate of the trivalent arsenic can achieve 94.47% and the removal rate of the pentavalent arsenic can achieve 99.99% when the pH value of the system is 12 when the arsenic removal agent is adopted to perform the deep arsenic removal on the wastewater.

The present application relates to the technical field of microbial remediation, and provides a strain Solidesulfovibrio magneticus Sm-4 and its application. The strain Sm-4 has a reduction effect on SO4 2‑ and heavy metals, and has a solidification effect on heavy metals, thereby providing a bacterial resource for removing SO4 2‑ and heavy metals in AMD water bodies and heavy metal contaminated soil. The magnetic soil desulfurization vibrio Sm-4 provided by the present application can tolerate high-concentration SO4 2‑ and remove heavy metals, SO4 2‑ has a high reduction rate, and has a good treatment effect on SO4 2‑ and heavy metals in soil and water bodies, and has a wide application prospect in in-situ remediation technologies such as acid mine drainage, contaminated soil around waste mine areas, and heavy metal contaminated farmland soil.

In one aspect, the description relates to a continuous process for treating acid mine drainage while simultaneously recovering a high-quality rare-earth pre-concentrate suitable for the extraction of commercially valuable rare-earth oxides. In another aspect, the pre-concentrate contains approximately 0.1% to 5% rare-earth elements on a dry weight basis. In another aspect, the description relates to a method for processing the pre-concentrate to generate a loaded leach solution that does not form gels or emulsions and is suitable for processing by solvent extraction. In yet another aspect, the description relates to a system and plant for carrying out the described process. In yet another aspect, the description relates to a composition containing rare-earth elements produced by the process described herein.This summary is intended as an exploratory tool for search purposes in the particular technique and is not intended to be limiting to the present description.

The embodiment of the utility model provides acid mine wastewater treatment equipment. The acid mine wastewater treatment equipment comprises a reactor and a gas supply device, the reactor comprises a container and a membrane assembly arranged in the container, the membrane assembly is used for attaching a biological membrane and provided with a gas inlet, and the gas supply device is communicated with the gas inlet of the membrane assembly and used for supplying a gaseous electron donor to the membrane assembly. According to the acid mine wastewater treatment equipment disclosed by the embodiment of the utility model, the biological activity of sulfate reducing bacteria is relatively strong, the sulfate reducing efficiency is relatively high, metal precipitates are easy to precipitate and collect, and the difficulty and the cost of callback to neutrality are relatively low and even callback to neutrality is not needed.

The application provides a comprehensive treatment method for acid mine wastewater, and belongs to the field of mine wastewater treatment. The method sequentially processes the wastewater through three stages of iron removal pretreatment, copper recovery by replacement and neutralization treatment. First, the pH value of the wastewater is adjusted in the iron removal reaction tank for reaction, and after solid-liquid separation, part of the underflow is backflowed, and the rest is introduced into the pressure filtration system. Then, the liquid after iron removal is introduced into the copper recovery reaction tank, copper is recovered through a reducer and iron powder system, underflow backflow and pressure filtration treatment are performed. Finally, the liquid after copper recovery is adjusted in the neutralization reaction tank, and the pH value is oxidized, and then solid-liquid separation and underflow backflow are performed, so that the wastewater can be finally discharged up to the standard, and deep purification of the acid mine wastewater is realized. The slag produced by the method provided by the application is a general industrial solid waste, which reduces the environmental risk of waste slag storage. The whole process optimizes the reaction efficiency through underflow backflow, realizes efficient recovery of copper and stable treatment of wastewater up to the standard.

This invention relates to a process for treating acidic mine wastewater (AMD). The process includes the following steps: adjusting the pH of the AMD to a range of 3 to 5; adding magnetite nanoparticles to form a slurry; and a) aerating the slurry obtained in step 3), or b) simultaneously heating and mixing the slurry obtained in step 3). The magnetite nanoparticles loaded with one or more metals and sulfate ions and precipitated metals are then separated from the slurry.

The invention discloses a low-calcium fly ash modification method and application thereof in coal mine acid mine water treatment.The low-calcium fly ash modification method comprises the steps that Ca (OH) 2-Na2CO3-MgO-power plant desulfurized gypsum slag is adopted as a composite modifier, and the effective CaO content in low-calcium fly ash is increased to 22% or above through the synergistic effect of calcium source strengthening, alkali excitation acceleration, Ca element stabilization and pore structure optimization; the modified fly ash can efficiently neutralize the acidity of coal mine producing acidic mine water (AMD) and synchronously adsorb and remove Fe < 3 + > and Mn < 2 + > in water, the pH of the treated AMD is stabilized at 6-9, the removal rates of Fe < 3 + > and Mn < 2 + > are both greater than or equal to 98%, and high-value utilization of the low-calcium fly ash and low-cost treatment of the AMD are realized.

The application discloses an acid mine drainage treatment system and a use method thereof, and belongs to the technical field of acid mine drainage treatment. The acid mine drainage treatment system comprises an iron removal device, a neutralization device and a control device, and is characterized in that the iron removal device comprises an adjusting pool, an injection pipe arranged at the side end of the adjusting pool, a reaction mechanism arranged beside the adjusting pool, a first conveying mechanism connecting the reaction mechanism and the adjusting pool, an iron precipitation pool arranged beside the reaction mechanism, and a first connecting pipe connecting the reaction mechanism and the iron precipitation pool; the neutralization device comprises a neutralization mechanism arranged beside the iron precipitation pool, a second conveying mechanism connecting the iron precipitation pool and the neutralization mechanism, a neutralization precipitation pool arranged beside the neutralization mechanism, a second connecting pipe connecting the neutralization mechanism and the neutralization precipitation pool, a third conveying mechanism arranged at one side of the neutralization precipitation pool and a siphon mechanism. The application can realize the treatment of acid mine drainage, resource recycling and mine filling.

In one aspect, the disclosure relates to a continuous process for treating acid mine drainage while simultaneously recovering a high-grade rare earth preconcentrate suitable for extraction of commercially valuable rare earth oxides. In a further aspect, the preconcentrate is from about 0.1% to 5% rare earth elements on a dry weight basis. In another aspect, the disclosure relates to a method for processing the preconcentrate to generate a pregnant leach solution that does not form gels or emulsions and is suitable for processing via solvent extraction. In another aspect, the disclosure relates to a system and plant for carrying out the disclosed process. In still another aspect, the disclosure relates to a composition containing rare earth elements produced by the process disclosed herein. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.

The invention relates to the technical field of wastewater treatment, and discloses acid mine wastewater treatment equipment and process based on microorganisms. The equipment comprises a shell, the two ends of the shell communicate with a water inlet tank and a water drainage tank correspondingly, a top plate is arranged on the shell, and a first electric telescopic rod is fixedly installed on the top plate; a lifting plate is fixedly mounted at the output end of the first electric telescopic rod, a plurality of groups of mounting racks distributed at intervals are fixedly mounted on the lifting plate, the outer side surfaces of the mounting racks are in contact with the inner wall of the shell, biological stuffing is arranged in the mounting racks, and a plurality of groups of blanking grooves corresponding to the mounting racks in position are formed in the inner bottom surface of the shell. The mine acid wastewater treatment device has the beneficial effects that in the mine acid wastewater treatment process, precipitates are cleaned in time, separation of the precipitates and the mine acid wastewater is achieved, and the mine acid wastewater treatment efficiency is guaranteed.

This invention discloses a method for selectively recovering copper, lead, and arsenic from acidic mining wastewater, comprising the following steps: 1) preparing iron-manganese oxides with strong stability under acidic conditions; 2) converting acidic mining wastewater containing copper, cadmium, lead, arsenic, and zinc into copper-cadmium-zinc enriched wastewater and lead-arsenic enriched iron-manganese oxides; 3) converting the lead-arsenic enriched iron-manganese oxides into a lead-containing solution and arsenic-enriched iron-manganese oxides; 4) converting the arsenic-enriched iron-manganese oxides into an arsenic-containing solution and arsenic-loaded iron-manganese oxides; 5) converting copper-cadmium-zinc enriched wastewater into cadmium-zinc enriched wastewater and copper-enriched iron-manganese oxides; 6) desorbing copper from the copper-enriched iron-manganese oxides to obtain a copper-containing solution. This invention can separately enrich and recover copper, lead, and arsenic from acidic mining wastewater, achieving the recovery and utilization of heavy metal resources while treating heavy metal-polluted wastewater, and has a very broad application prospect.

The present application relates to a kind of composite strains and its application in coal gangue and acid mine drainage treatment and rare earth leaching, belong to environmental microbial repair, mine solid waste resource and rare earth biological leaching technical field.The composite strain of the present application includes Acidithiobacillus ferrooxidans WZ33 and acid deposit acidophilic thiobacillus WY33;The preservation number of the Acidithiobacillus ferrooxidans is: CGMCC No.37726;The preservation number of the acid deposit acidophilic thiobacillus is CGMCC No.38196.Acidithiobacillus ferrooxidans (A. ferrooxidans WZ33) in the present application is mainly responsible for ferrous oxidation, rapid acid production and Fe 3+ Oxidizing agent is generated;Acid deposit acidophilic thiobacillus (A. acidisediminis WY33) is mainly responsible for sulfur material oxidation, eliminate sulfur passivation film, continuously maintain low pH environment.The two form complementary synergic system, significantly improve leaching and processing efficiency, better than single strain.

The application discloses a wastewater treatment device, an acid mine drainage purification system and a treatment method, and belongs to the field of wastewater treatment.The device comprises a limestone interception zone, a biochar interception zone, a confluence ditch, a first-stage sedimentation tank, a first-stage adsorption filter dam, a neutralization dam, a second-stage sedimentation tank, a second-stage adsorption filter dam, an anaerobic fermentation tank, a first-stage subsurface flow tank, a second-stage subsurface flow tank and a submerged plant tank which are sequentially connected.The treatment method based on the system comprises the following steps: intercepting the source of surface and shallow soil, preliminarily depositing and adsorbing and filtering the wastewater after the wastewater is collected, performing secondary neutralization and sedimentation treatment on the wastewater, then performing anaerobic fermentation, finally performing wetland purification treatment, and burning and recycling heavy metals from the planted plants.The purification system has the advantages of low investment cost, simple operation, convenient maintenance, low energy consumption, significantly improved water quality and suitability for ecological management of acid mine drainage.

The application provides a system and method for enriching and recovering rare earth elements in acid mine wastewater, and belongs to the technical field of rare earth element recovery. The system for enriching and recovering rare earth elements in acid mine wastewater comprises an adjusting pool, a sludge washer, a neutralizer, a buffer pool, a first reactor, a second reactor, a filter, a first dewatering pool, a second dewatering pool, an acid pickling soaking pool and a sludge dewatering pool. The system is used for recovering rare earth elements, the pH value of the acid mine wastewater is increased by adding an alkaline substance, the reagent cost for recovering the rare earth elements is significantly reduced, the dewatered sludge is pickled, the rare earth elements adhered to the dewatered sludge are transferred to the leaching solution through the pickling, the leaching solution is returned to the buffer pool again, the loss of the rare earth elements is further reduced, and the recovery rate of the rare earth elements is improved.

The application discloses an acid mine water producing site integrated prevention and treatment system and method, which comprises a pretreatment part, a treatment part, a solid-liquid separation part and an acid return prevention part. The outlet of the pretreatment part is connected with the inlet of the treatment part. The first outlet of the treatment part is connected with the inlet of the solid-liquid separation part. The second outlet of the treatment part and the liquid outlet of the solid-liquid separation part are both connected with the inlet of the acid return prevention part. The application has scientific principles and is easy to operate. The application can be used for treating acid mine water on site of a coal mine, so that the treated wastewater can meet the discharge standard and no longer return acid. The microbial electrolysis device can degrade sulfate ions in the wastewater more completely, so that energy can be saved, addition of pH adjusting reagents can be avoided, treatment cost can be reduced, secondary pollution can be avoided, fine sulfur ore can be obtained after treatment, and economic and environmental benefits can be achieved.

The present invention discloses a carbon sink calculation method for a metal mine restoration area, which belongs to the field of carbon sink detection technology. The method comprises the following steps: dividing the metal mine restoration area into a plurality of different ecological region quadrats, calculating the sum of carbon reserves in different ecological regions, and recording it as C. E ; Soil samples were collected to assess the impact of soil erosion on carbon storage in the metal mine restoration area. By measuring the amount of soil erosion and the organic carbon content of the surface soil, the carbon loss caused by soil erosion was calculated, which was recorded as C SE Assess the impact of acid mine drainage treatment on carbon emissions in the remediation area. By obtaining the runoff conditions and relevant carbon emission factors in the remediation area, calculate the carbon emissions (GHG) generated by acid mine drainage treatment. E ; Set the measurement period and calculate the total carbon sink ΔC in the metal mine restoration area during the measurement period according to the formula T The carbon sink calculation method of the present invention can provide a comprehensive and quantitative assessment of the total carbon sink capacity of a mine restoration area.

The application discloses a method for treating acid mine drainage by biopassivation of sulfur-containing mine waste rock at a source, and belongs to the field of mine environment treatment. The method comprises the following steps: using acidophilic microorganisms to induce an external iron source to form a passivation film on the surface of the sulfur-containing mine waste rock, so as to isolate oxygen, water and microorganisms from the sulfur-containing mine waste rock, and reduce the generation of acid mine drainage. The external iron source is widely available, the whole process is simple to operate, and the cost is low. The method can inhibit the biological / chemical dissolution of the sulfur-containing mine waste rock, and reduce the generation of acid mine drainage at a source, and therefore, has important significance for source treatment of acid mine drainage in coal mines and non-ferrous metal mines.

1006792108 Abstract In one aspect, the disclosure relates to a continuous process for treating acid mine drainage while simultaneously recovering a high-grade rare earth preconcentrate suitable for extraction of commercially valuable rare earth oxides. In a further aspect, the preconcentrate is from about 0.1% to 5% rare earth elements on a dry weight basis. In another aspect, the disclosure relates to a method for processing the preconcentrate to generate a pregnant leach solution that does not form gels or emulsions and is suitable for processing via solvent extraction. In another aspect, the disclosure relates to a system and plant for carrying out the disclosed process. In still another aspect, the disclosure relates to a composition containing rare earth elements produced by the process disclosed herein. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure. Abstract 20 26 21 40 86 07 A ug 2 02 6 1 0 0 6 7 9 2 1 0 8 A b s t r a c t 2 0 2 6 2 1 4 0 8 6 0 7 2 0 2 6 A u g

The invention discloses a combined treatment process for treatment of difficult-to-treat acid mine wastewater. The combined treatment process comprises the following steps: conveying the acid mine wastewater into a pre-precipitation tank, and introducing hydrogen sulfide gas for pre-precipitation; supernate in the pre-sedimentation tank is conveyed into a biological mineralization tank to be subjected to biological mineralization treatment; the effluent of the biomineralization pool is subjected to gradient pH regulation and control for treatment, wherein the gradient pH regulation and control comprises first-stage pH regulation and control, first-stage flocculent precipitation, second-stage pH regulation and control, second-stage flocculent precipitation and third-stage pH regulation and control; and feeding the gradient pH three-stage regulation and control effluent into a deep desulfurization tank for deep desulfurization, and returning hydrogen sulfide gas generated by the deep desulfurization tank to the pre-sedimentation tank for cyclic utilization. According to the invention, wastewater treatment is carried out through a physical-chemical-biological-micro-electric coupling process, the defects that heavy metals in the effluent of acid mine wastewater are difficult to reach the standard, the use amount of chemicals is large, the generation amount of sludge is large and the desulfurization cost is high are overcome, meanwhile, by-products such as Schwertmannite and sulfurized heavy metals can be recovered, and the final effluent is ensured to stably reach the standard.

In one aspect, the disclosure relates to methods for recovering metal compounds from mine waste, wherein the mine waste comprises at least one metal. Also disclosed herein are methods related to recovering metal compounds from acid mine drainage, wherein the acid mine drainage waste comprises at least one metal. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.