CN111992258B - Method for treating heavy metal pollution in sulfide ore tailings - Google Patents

Method for treating heavy metal pollution in sulfide ore tailings Download PDF

Info

Publication number
CN111992258B
CN111992258B CN202010922047.9A CN202010922047A CN111992258B CN 111992258 B CN111992258 B CN 111992258B CN 202010922047 A CN202010922047 A CN 202010922047A CN 111992258 B CN111992258 B CN 111992258B
Authority
CN
China
Prior art keywords
tailings
bentonite
suspension
heavy metal
sulfide
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202010922047.9A
Other languages
Chinese (zh)
Other versions
CN111992258A (en
Inventor
王桂芳
肖慧珍
朱金良
杨金林
马少健
丁晨辉
刘娜
王翼文
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Guangxi University
Original Assignee
Guangxi University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Guangxi University filed Critical Guangxi University
Priority to CN202010922047.9A priority Critical patent/CN111992258B/en
Publication of CN111992258A publication Critical patent/CN111992258A/en
Application granted granted Critical
Publication of CN111992258B publication Critical patent/CN111992258B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J39/00—Cation exchange; Use of material as cation exchangers; Treatment of material for improving the cation exchange properties
    • B01J39/08—Use of material as cation exchangers; Treatment of material for improving the cation exchange properties
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/42—Treatment of water, waste water, or sewage by ion-exchange
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/42—Treatment of water, waste water, or sewage by ion-exchange
    • C02F2001/425—Treatment of water, waste water, or sewage by ion-exchange using cation exchangers
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/20—Heavy metals or heavy metal compounds
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/10—Nature of the water, waste water, sewage or sludge to be treated from quarries or from mining activities

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Water Supply & Treatment (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

The invention discloses a method for treating heavy metal pollution in sulfide ore tailings, which comprises the following steps: mixing calcium bentonite suspension with solid Na 2 CO 3 Performing sodium treatment to obtain a sodium-treated bentonite suspension, aging, adding a modifier for modification to obtain modified bentonite, drying and grinding to obtain a treatment material; mixing the treatment material with the sulfide ore tailings and the simulated acid rain solution, oscillating at a constant speed, and filtering and leaching the mixture to obtain the treated tailing leachate. The raw material calcium bentonite used in the method is low in price, and the requirement on the environment is low due to the use of few organic modifiers; meanwhile, the method of the invention has simple operation and good curing effect, and is convenient for use in industrial production.

Description

Method for treating heavy metal pollution in sulfide ore tailings
Technical Field
The invention belongs to the field of tailing treatment, and particularly relates to a method for treating heavy metal pollution in sulfide tailing.
Background
Most of metal mines in China are primary sulfide deposits, and a large amount of sulfide tailings are left after mining and mineral dressing. The sulfide minerals react with moisture and oxygen in the air under natural environment to generate sulfuric acid through acidification, and the sulfide ore tailings can form acidic mine wastewater under the leaching action of rainwater and promote the dissolution of heavy metals in the tailings. Heavy metals are not easy to degrade in soil, can stably exist for a long time, and have great toxic effect on the environment even at low concentration. Heavy metals can be absorbed and enriched in the plant body through the roots of the plant, so that the growth and development of the plant are influenced, and even the plant withers; and the food can enter human bodies and animal bodies through food chains, and the growth, development and metabolism of the human bodies and the animal bodies are damaged. Disasters and environmental hazards caused by heavy metals worldwide are common: water preferably acquired from organic mercury pollution such as japan and bone softening and bone atrophy from cadmium pollution; the cadmium, lead and arsenic of a certain factory in Sweden exceed the standards, so that the natural abortion rate and the fetal teratogenesis rate of local female workers are obviously increased. Wang Shaohua and the like, through the sampling analysis of soil, water and plants around the tailings pond of Yang Shanchong, anhui copper-mausoleum Leonii, the results show that the content of heavy metal elements, especially As and Cu, in the soil around the tailings pond is high, wherein the content of Cu in the cover soil in the tailings pond exceeds the national soil three-level standard by 2 times, and the content of As exceeds the national soil three-level standard by 100 times. Wang Zhilou and the like analyze and research the heavy metal pollution condition and the composite pollution characteristics of agricultural soil around the Dexing copper mine tailing pond, and research shows that the soil around the tailing pond is polluted by Cu, zn, ni, pb, cr and Cd in different degrees, wherein the pollution of Cu and Cd is the most serious and exceeds the national second-level soil standard. Therefore, heavy metals in the sulfide tailings must be treated.
Because the dissolution of the heavy metal ions in the tailing pond is a long-term and slow process, the engineering cost for specially treating the waste water is high, and the heavy metal ions can be continuously dissolved out and continuously pollute the surrounding environment as long as the source tailing pond is not treated. Therefore, the core problem of controlling heavy metal pollution of sulfide ore tailings is source control in the reservoir. The reason for releasing heavy metal ions from sulfide ore tailings is mainly O 2 、Fe 3+ And the action of microorganisms, so that some researchers propose several in-library source control methods, such as a neutralization method, a bactericide method, an isolation method, a passivation coating method and the like.
The neutralization method is to fill a tailing pond with alkaline substances such as limestone, lime, caustic soda, industrial fly ash and ferrous oxide together with sulfur-containing tailings to increase the pH value of tailing leachate so as to control the release of heavy metals. The covering method is to use water, sludge and clayThe method is to cover the mine surface with materials such as soil, crushed stone and wood to isolate oxygen. Thiobacillus ferrooxidans (A.f) can promote Fe 2+ Is oxidized into Fe 3+ And is Fe 3+ The oxidation rate for pyrite is 106 times that for oxygen. 5363 the existence of bacteria A.f can accelerate oxidation of pyrite in sulfide ore tailings, and in order to inhibit A.f bacteria, bactericide is used for inhibiting activity of microorganism and reducing Fe 2+ Is oxidized into Fe 3+ Thereby slowing the oxidation of the sulphide ore tailings to prevent the production of AMD. There are reports in the literature that tailing passivators are used to inhibit tailing oxidation, and adsorbing materials such as peanut shells, rice straws and corn stalks are used to remove heavy metal and sulfate ions. However, these methods are difficult to operate, high in economic cost and volatile. Therefore, a method for treating heavy metals in the sulfide ore tailings, which can overcome the above problems, needs to be found.
Disclosure of Invention
In view of the above, the invention aims to provide a method for treating heavy metal pollution in sulfide tailings, which has the advantages of simple process, cheap and easily available raw materials, and greatly reduced heavy metal elution amount in the treated sulfide tailings.
A method for treating heavy metal pollution in sulfide ore tailings comprises the following steps:
(1) Preparing calcium bentonite and deionized water into a first suspension with 5-7% of ore pulp concentration, stirring in a constant-temperature water bath at 60-75 ℃ to uniformly disperse, and adding solid Na 2 CO 3 Continuously stirring for 1-2 h to obtain a second suspension; wherein solid Na 2 CO 3 The dosage is 1-5% of the weight of the calcium bentonite;
(2) Aging the second suspension for 1-2 h, adding a modifier, stirring for 3-4 h in a constant-temperature water bath at 60-75 ℃, centrifuging for 20-30 min, removing supernatant, washing and separating the obtained precipitate with deionized water, and repeating centrifuging and washing for multiple times to obtain modified bentonite; the modifier is selected from at least one of 1,6 hexanediamine (DA), triethylene Tetramine (TTA), tetraethylene pentamine (TEPA) and sodium diethyldithiocarbamate (DDTC), and the using amount of the modifier is 95mmol/100g calcium bentonite;
(3) Drying the modified bentonite at 85-95 ℃, and then grinding and sieving to obtain a sulfide tailing treatment material;
(4) Mixing the sulfide ore tailings, the treatment material and the simulated acid rain solution at 30-40 ℃, oscillating for 1-72 hours at a constant speed, and filtering and leaching the mixture to obtain a treated tailings leachate, wherein the ratio of the sulfide ore tailings, the treatment material and the simulated acid rain solution is 10g: 0.5-2 g:30 to 50mL.
In a preferred technical scheme, in the step (1), the concentration of the ore pulp of the first suspension is 6%, and the first suspension is stirred in a constant-temperature water bath at 70 ℃ for 10-20 min, preferably 15min.
In the preferable technical scheme, in the step (1), solid Na is added 2 CO 3 Then stirring is continued for 90min.
In a preferable technical scheme, in the step (2), the temperature of the thermostatic waterbath is 70 ℃, and the stirring time is 4 hours.
In a preferred embodiment, in step (2), the centrifuging and washing are performed multiple times by: after the supernatant liquid is removed by centrifugal separation, deionized water is injected into the precipitate obtained by separation to dilute the precipitate to two times, the mixture is stirred evenly, and the centrifugal separation and the water injection dilution are repeated for 3 to 5 times.
In a preferred technical scheme, in the step (3), the drying time is 24-48 h, preferably 24h.
In a preferred embodiment, in step (3), the ground and sieved particle size is-200 mesh (less than 200 mesh), i.e., 0.074 μm size fraction.
In the preferred technical scheme, in the step (4), the sulfide tailings, the treatment material and the simulated acid rain solution are mixed at 30 ℃.
In a preferred technical scheme, in the step (4), the constant oscillation speed is 200rpm.
In the preferred technical scheme, in the step (4), the ratio of the sulfide ore tailings, the treatment material and the simulated acid rain solution is 10g:1g:40mL.
The method uses sodium carbonate to perform sodium treatment on the calcium bentonite with weak solidification capability, changes the surface property of the calcium bentonite, expands the interlayer distance of the calcium bentonite, and improves the cation exchange capability of the calcium bentonite; further, the bentonite is organically modified by using a modifier, so that the chemical bond force between the bentonite and heavy metals is increased, and the modified bentonite is obtained; based on the self-adsorption of the bentonite and the complexing effect of the modifier intercalation on heavy metal ions, the heavy metal is solidified under specific conditions, so that the elution amount of the heavy metal in the sulfide tailings is reduced, and the heavy metal pollution treatment in the sulfide tailings is realized. The invention takes two lead-zinc mine tailings in different producing areas and three tin polymetallic mine tailings with different weathering degrees as research objects, researches the heavy metal ion dissolution rules of five sulfide mine tailings before and after treatment, finds that the method has good curing effect on sulfide mine tailings with different acid-producing potentials or different types, can effectively reduce the heavy metal dissolution amount of the sulfide mine tailings, and achieves the environmental protection purpose of treating heavy metal pollution in the sulfide mine tailings.
Compared with the prior art, the invention has the following beneficial technical effects:
the raw material calcium bentonite used in the method is low in price, and the requirement on the environment is low due to the use of few organic modifiers; meanwhile, the method of the invention has simple operation and good curing effect, and is convenient for use in industrial production.
Drawings
FIG. 1A is a comparison of XRD patterns of a raw material calcium-based bentonite (R-Mt, also called Ca-Mt), a sodium-modified bentonite (Na-Mt) obtained in step (1) of example 1, and sulfide ore tailing treatment materials (DA-Mt, TTA-Mt, DDTC-Mt and TEPA-Mt) obtained in step (3) of examples 1 to 4.
Fig. 1B is an SEM image of the raw material calcium bentonite.
Fig. 1C is an SEM image of the sulphide ore tailings remediation material obtained in step (3) of example 1.
Fig. 1D is an EDS diagram of the sulphide ore tailings remediation material obtained in step (3) of example 1.
FIG. 2A is a graph of the cumulative elution amount of heavy metal Zn in the tailings after the solidification of certain lead-zinc tailings (F) by different sulfide tailings treatment materials (DA-Mt, TTA-Mt and TEPA-Mt) in examples 2-4 for different reaction times (2 h, 4h, 8h, 24h, 48h and 72 h).
FIG. 2B is a graph of the cumulative elution amount of heavy metal Mn in the tailings of a lead-zinc mine (F) after solidification of different sulfide tailings treatment materials (DA-Mt, TTA-Mt and TEPA-Mt) in examples 2 to 4 and different reaction times (2 h, 4h, 8h, 24h, 48h and 72 h).
FIG. 2C is a graph of the cumulative elution amount of heavy metal As in the tailings after the solidification of a certain lead-zinc tailings (F) by different sulfide tailings treatment materials (DA-Mt, TTA-Mt and TEPA-Mt) in examples 2-4 for different reaction times (2 h, 4h, 8h, 24h, 48h and 72 h).
FIG. 2D is a graph showing the cumulative elution amount of heavy metal Pb in the cured tailings of a lead-zinc mine tailings (F) obtained by carrying out different reaction times (2 h, 4h, 8h, 24h, 48h and 72 h) on different sulfide mine tailing treatment materials (DA-Mt, TTA-Mt and TEPA-Mt) in examples 2 to 4.
FIG. 3A is a graph of the cumulative elution amount of heavy metal Zn after curing DDTC-Mt on different sulfide ore tailings (F, YD, CH1, CH2 and CH 3) for different times (2 h, 4h, 8h, 24h, 48h and 72 h) in examples 5-9.
FIG. 3B is a graph of the cumulative elution amount of heavy metal Mn after curing DDTC-Mt for different sulfide ore tailings (F, YD, CH1, CH2, CH 3) for different times (2 h, 4h, 8h, 24h, 48h, 72 h) in examples 5-9.
FIG. 3C is a graph showing the cumulative elution amounts of heavy metal As after curing the DDTC-Mt of examples 5 to 9 for different times (2 h, 4h, 8h, 24h, 48h, 72 h) of the sulfide ore tailings (F, YD, CH1, CH2, CH 3).
FIG. 3D is a graph showing the cumulative elution amount of heavy metal Pb after curing of DDTC-Mt in examples 5 to 9 for different times (2 h, 4h, 8h, 24h, 48h, 72 h) of sulfide ore tailings (F, YD, CH1, CH2, CH 3).
Fig. 4A is a graph of the cumulative elution amount of the heavy metal Zn of five tailings without adding the tailing treatment material in comparative example 1 after elution for different time periods (2 h, 4h, 8h, 24h, 48h, 72 h).
Fig. 4B is a graph of the cumulative elution amount of heavy metal Mn after five tailings without added tailing treatment materials in comparative example 1 are eluted for different time periods (2 h, 4h, 8h, 24h, 48h and 72 h).
Fig. 4C is a graph of the cumulative elution amounts of heavy metal As after five tailings without added tailing treatment materials in comparative example 1 were eluted for different times (2 h, 4h, 8h, 24h, 48h, 72 h).
Fig. 4D is a graph showing the cumulative elution amount of heavy metal Pb after five kinds of tailings without addition of the tailing treatment material in comparative example 1 are eluted for different times (2 h, 4h, 8h, 24h, 48h, 72 h).
FIG. 5 is a graph showing the cumulative elution amounts of heavy metals Zn, mn, as and Pb from bentonite raw ore in comparative example 2 after 4 hours of solidification of five tailings.
Detailed Description
In order to better explain the present invention and facilitate the understanding of the technical solutions of the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the following examples are illustrative only and do not represent or limit the scope of the present invention, which is defined by the claims.
The reagents and instruments used in the following examples are conventional products which are commercially available, although manufacturers thereof are not indicated. For example, inductively coupled plasma mass spectrometers, model: plasma Quant MS from Jena Analytik Jena AG, germany.
Five tailing samples are respectively collected in three different mining areas, wherein two tailing samples are respectively collected from weathered tailings (YD for short) of a tailing pond of a lead-zinc ore dressing plant in Neimengyufeng city and tailings (F for short) weathered for years of the tailing pond of the lead-zinc ore dressing plant in Guangxi Wufeng city, and the other three tailing samples are collected from three tailings with different weathered degrees of a tailing pond of a tin polymetallic ore dressing plant in Guangxi Nandan county, and are respectively named as fresh tailings (marked as CH 1), weathered tailings (marked as CH 2) and weathered tailings sediment (marked as CH 3). The fresh tailings are taken from a discharge port of a tailing pond, are dark gray in color and are named as fresh tailings because of short oxidation time; the weathered tailings are surface tailings which are collected from the surface of the tailings pond and weathered for 2-3 years, and the color of the surface tailings is slightly darker than that of fresh tailings; the tailings deposit is the tailings which are collected from a tailings pond and piled for more than ten years, and is gray brown. The tailings YD are white and grey; the tailings F are earthy yellow due to weathering for many years. The five tailing samples belong to sulfide tailings, are all tailings which are taken from 0-25 cm below the surface layer of a tailing pond, are sampled according to a uniform point distribution method, and are naturally air-dried, crushed and uniformly mixed for later use.
The bentonite sample used in the experiment is calcium bentonite (Ca-Mt) in certain producing area of inner Mongolia, and the chemical component is SiO 2 And Al 2 O 3 Mainly accounting for 64.37 percent and 16.05 percent of SiO respectively 2 、Al 2 O 3 The content ratio of (A) to (B) is 4.01 2 O 3 And CaO in a relatively high amount, with a blue absorption of 43.7g/100g, a cation exchange capacity of 89mmol/100g and a d (001) value of 1.50nm.
X-ray diffraction analysis (XRD) an X-ray diffractometer (SMARTLAB 3 KW) manufactured by Japan K.K., and an oriented piece was formed by a natural sedimentation method to perform structural analysis of phase composition and the like of a sample. The test conditions were: and a continuous scanning mode is adopted, the scanning range is 2 theta = 3-80 degrees, and the scanning speed is 8 degrees (2 theta)/min.
Interpretation of terms:
concentration of ore pulp: the pulp is a mineral slurry. After the minerals are dispersed in the liquid to form a solution, the content of the minerals in the solution is the pulp concentration. The following pulp concentration refers to the bentonite content of the solution formed by bentonite and water.
Simulated acid rain solution pH 4.5: adding a mixed solution of concentrated sulfuric acid and concentrated nitric acid with a volume ratio of 4.8 to deionized water, recording the obtained solution as an acid rain stock solution, then adding water to dilute the acid rain stock solution according to acid rain grade division, and blending the acid rain stock solution into a simulated acid rain solution with pH of 4.5.
Example 1
(1) Weighing 40g of calcium bentonite, placing the calcium bentonite in a glass beaker with the capacity of 1L, and adding deionized water to prepare suspension with the pulp concentration of 6% (namely, the mass fraction of the calcium bentonite is 6%); stirring the suspension in water bath, electrically stirring at 70 deg.C for 15min, dispersing the suspension, and adding 2.0g (5 wt% of calcium bentonite) of analytically pure solid Na 2 CO 3 Stirring for 90min to obtainSuspension of sodium bentonite;
(2) Aging the suspension of the sodium bentonite for 2 hours, adding a modifier sodium diethyldithiocarbamate (DDTC), stirring for 4 hours in a constant-temperature water bath at 70 ℃, centrifugally separating to remove supernatant, injecting deionized water into the precipitate obtained by separation to dilute the precipitate to two times, uniformly stirring, centrifugally separating again, injecting water to dilute the precipitate for 3 to 5 times, and washing off the excessive modifier on the surface of the precipitate, wherein the dosage of the modifier is 38mmol;
(3) And (3) putting the washed modified bentonite sample into an oven, drying for 24 hours at 95 ℃, grinding the sample by using an agate container mortar, and sieving the ground sample by using a 200-mesh sieve to prepare a sulfide ore tailing treatment material, which is marked as DDTC-Mt.
(4) Weighing 10g of certain lead-zinc ore tailings (F) and placing the tailings in an erlenmeyer flask, and adding 1g of DDTC-Mt and 40ml of simulated acid rain solution with the pH value of 4.5, wherein the reaction temperature is 30 ℃. After shaking at a constant speed (200 rpm) for 4h with a shaker, the mixture in the erlenmeyer flask was filtered and filtered (0.45 μm filter membrane) to obtain a treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Example 2
(1) Weighing 40g of calcium bentonite, placing the calcium bentonite in a glass beaker with the capacity of 1L, and adding deionized water to prepare suspension with the pulp concentration of 6% (namely, the mass fraction of the calcium bentonite is 6%); stirring the suspension in water bath, electrically stirring at 70 deg.C for 15min, dispersing the suspension, and adding 2.0g (5 wt% of calcium bentonite) of analytically pure solid Na 2 CO 3 Continuously stirring for 90min to obtain suspension of sodium bentonite;
(2) Aging the suspension of the sodium bentonite for 2 hours, adding a modifier 1,6 hexamethylene Diamine (DA), stirring for 4 hours in a constant-temperature water bath at 70 ℃, centrifugally separating to remove supernatant, injecting deionized water into the separated precipitate to dilute to two times, uniformly stirring, centrifugally separating again and injecting water to dilute, repeating for 3-5 times, and washing off the redundant modifier on the surface of the precipitate, wherein the dosage of the modifier is 38mmol;
(3) And (3) putting the washed modified bentonite sample into an oven, drying for 24 hours at 95 ℃, grinding the sample by using an agate container mortar, and sieving the ground sample by using a 200-mesh sieve to prepare a sulfide ore tailing treatment material which is marked as DA-Mt.
(4) Weighing 10g of certain lead-zinc ore tailings (F) and placing the tailings in an erlenmeyer flask, and adding 1g of DA-Mt and 40ml of simulated acid rain solution with the pH value of 4.5, wherein the reaction temperature is 30 ℃. After shaking for 2h, 4h, 8h, 24h, 48h and 72h respectively at a constant speed (200 rpm) by using a shaker, sampling the mixture in the conical flask, filtering and filtering (0.45 mu m filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Example 3
(1) Weighing 40g of calcium bentonite, placing the calcium bentonite in a glass beaker with the capacity of 1L, and adding deionized water to prepare suspension with the pulp concentration of 6% (namely, the mass fraction of the calcium bentonite is 6%); stirring the suspension in water bath, electrically stirring at 70 deg.C for 15min, dispersing the suspension, and adding 2.0g (5 wt% of calcium bentonite) of analytically pure solid Na 2 CO 3 Continuously stirring for 90min to obtain suspension of sodium bentonite;
(2) Aging the suspension of the sodium bentonite for 2 hours, adding a modifier triethylenetetramine (TTA), stirring for 4 hours in a constant-temperature water bath at 70 ℃, centrifugally separating to remove supernatant, injecting deionized water into the precipitate obtained by separation to dilute the precipitate to twice, stirring uniformly, centrifugally separating again, injecting water to dilute the precipitate for 3 to 5 times, and washing off the excessive modifier on the surface of the precipitate, wherein the dosage of the modifier is 38mmol;
(3) And (3) putting the washed modified bentonite sample into an oven, drying for 24 hours at 95 ℃, grinding the sample by using an agate container mortar, and sieving the ground sample by using a 200-mesh sieve to prepare a sulfide ore tailing treatment material which is marked as TTA-Mt.
(4) 10g of lead-zinc ore tailings (F) are weighed and placed in an erlenmeyer flask, and 1g of TTA-Mt and 40ml of simulated acid rain solution with the pH value of 4.5 are added, wherein the reaction temperature is 30 ℃. After shaking for 2h, 4h, 8h, 24h, 48h and 72h respectively at a constant speed (200 rpm) by using a shaker, sampling the mixture in the conical flask, filtering and filtering (0.45 mu m filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Example 4
(1) Weighing 40g of calcium bentonite, placing the calcium bentonite in a glass beaker with the capacity of 1L, and adding deionized water to prepare suspension with the pulp concentration of 6% (namely, the mass fraction of the calcium bentonite is 6%); stirring the suspension in water bath, electrically stirring at 70 deg.C for 15min, dispersing the suspension, and adding 2.0g (5 wt% of calcium bentonite) of analytically pure solid Na 2 CO 3 Continuously stirring for 90min to obtain suspension of sodium bentonite;
(2) Aging the suspension of the sodium bentonite for 2 hours, adding a modifier Tetraethylenepentamine (TEPA), stirring for 4 hours at the temperature of constant-temperature water bath of 70 ℃, centrifugally separating to remove supernatant, injecting deionized water into the separated precipitate to dilute the precipitate to two times, uniformly stirring, centrifugally separating again, injecting water to dilute the precipitate, repeating the steps for 3 to 5 times, and washing off the excessive modifier on the surface of the precipitate, wherein the dosage of the modifier is 38mmol;
(3) And (3) putting the washed modified bentonite sample into an oven, drying for 24 hours at 95 ℃, grinding the sample by using an agate ware mortar, and screening the ground sample through a 200-mesh screen to prepare a sulfide ore tailing treatment material, wherein the material is marked as TEPA-Mt.
(4) 10g of certain lead-zinc ore tailings (F) are weighed and placed in a conical flask, and 1g of TEPA-Mt and 40ml of simulated acid rain solution with the pH value of 4.5 are added, and the reaction temperature is 30 ℃. After shaking for 2h, 4h, 8h, 24h, 48h and 72h respectively at a constant speed (200 rpm) by using a shaker, sampling the mixture in the conical flask, filtering and filtering (0.45 mu m filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by adopting an inductively coupled plasma mass spectrometer.
Example 5
(1) Weighing 40g of calcium bentonite, placing the weighed calcium bentonite into a glass beaker with the capacity of 1L, adding deionized water to prepare the mixture with the pulp concentration of 6A suspension in percent (i.e., 6% by mass of calcium bentonite); stirring the suspension in water bath, electrically stirring at 70 deg.C for 15min, dispersing the suspension, and adding 2.0g (5 wt% of calcium bentonite) of analytically pure solid Na 2 CO 3 Continuously stirring for 90min to obtain suspension of sodium bentonite;
(2) Aging the suspension of the sodium bentonite for 2 hours, adding a modifier sodium diethyldithiocarbamate (DDTC), stirring for 4 hours in a constant-temperature water bath at 70 ℃, centrifugally separating to remove supernatant, injecting deionized water into the precipitate obtained by separation to dilute the precipitate to two times, uniformly stirring, centrifugally separating again, injecting water to dilute the precipitate for 3 to 5 times, and washing off the excessive modifier on the surface of the precipitate, wherein the dosage of the modifier is 38mmol;
(3) And (3) putting the washed modified bentonite sample into an oven, drying for 24 hours at 95 ℃, grinding the sample by using an agate ware mortar, and screening the ground sample through a 200-mesh screen to prepare a sulfide ore tailing treatment material, wherein the material is marked as DDTC-Mt.
(4) Weighing 10g of certain lead-zinc ore tailings (F) and placing the tailings in an erlenmeyer flask, and adding 1g of DDTC-Mt and 40ml of simulated acid rain solution with the pH value of 4.5, wherein the reaction temperature is 30 ℃. After shaking for 2h, 4h, 8h, 24h, 48h and 72h respectively at a constant speed (200 rpm) by using a shaker, sampling the mixture in the conical flask, filtering and filtering (0.45 mu m filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Example 6
(1) Weighing 40g of calcium bentonite, placing the calcium bentonite in a glass beaker with the capacity of 1L, and adding deionized water to prepare suspension with the pulp concentration of 6% (namely, the mass fraction of the calcium bentonite is 6%); stirring the suspension in water bath, electrically stirring at 70 deg.C for 15min, dispersing the suspension, and adding 2.0g (5 wt% of calcium bentonite) of analytically pure solid Na 2 CO 3 Continuously stirring for 90min to obtain suspension of sodium bentonite;
(2) Aging the suspension of the sodium bentonite for 2 hours, adding a modifier sodium diethyldithiocarbamate (DDTC), stirring for 4 hours in a constant-temperature water bath at 70 ℃, centrifugally separating to remove supernatant, injecting deionized water into the precipitate obtained by separation to dilute the precipitate to two times, uniformly stirring, centrifugally separating again, injecting water to dilute the precipitate for 3 to 5 times, and washing off the excessive modifier on the surface of the precipitate, wherein the dosage of the modifier is 38mmol;
(3) And (3) putting the washed modified bentonite sample into an oven, drying for 24 hours at 95 ℃, grinding the sample by using an agate container mortar, and sieving the ground sample by using a 200-mesh sieve to prepare a sulfide ore tailing treatment material, which is marked as DDTC-Mt.
(4) Weighing 10g of certain lead-zinc ore tailings (YD) and placing the tailings into a conical flask, and adding 1g of DDTC-Mt and 40ml of simulated acid rain solution with the pH value of 4.5, wherein the reaction temperature is 30 ℃. After shaking for 2h, 4h, 8h, 24h, 48h and 72h respectively at a constant speed (200 rpm) by using a shaker, sampling the mixture in the conical flask, filtering and filtering (0.45 mu m filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Example 7
(1) Weighing 40g of calcium bentonite, placing the calcium bentonite in a glass beaker with the capacity of 1L, and adding deionized water to prepare suspension with the pulp concentration of 6% (namely, the mass fraction of the calcium bentonite is 6%); stirring the suspension in water bath, electrically stirring at 70 deg.C for 15min, dispersing the suspension, and adding 2.0g (5 wt% of calcium bentonite) of analytically pure solid Na 2 CO 3 Continuously stirring for 90min to obtain suspension of sodium bentonite;
(2) Aging the suspension of the sodium bentonite for 2 hours, adding a modifier sodium diethyldithiocarbamate (DDTC), stirring for 4 hours in a constant-temperature water bath at 70 ℃, centrifugally separating to remove supernatant, injecting deionized water into the precipitate obtained by separation to dilute the precipitate to two times, uniformly stirring, centrifugally separating again, injecting water to dilute the precipitate for 3 to 5 times, and washing off the excessive modifier on the surface of the precipitate, wherein the dosage of the modifier is 38mmol;
(3) And (3) putting the washed modified bentonite sample into an oven, drying for 24 hours at 95 ℃, grinding the sample by using an agate container mortar, and sieving the ground sample by using a 200-mesh sieve to prepare a sulfide ore tailing treatment material, which is marked as DDTC-Mt.
(4) Weighing 10g of fresh tailings (CH 1) of a tin polymetallic ore, placing the fresh tailings in a conical flask, and adding 1g of DDTC-Mt and 40ml of simulated acid rain solution with the pH value of 4.5, wherein the reaction temperature is 30 ℃. After shaking for 2h, 4h, 8h, 24h, 48h and 72h respectively at a constant speed (200 rpm) by using a shaker, sampling the mixture in the conical flask, filtering and filtering (0.45 mu m filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Example 8
(1) Weighing 40g of calcium bentonite, placing the calcium bentonite in a glass beaker with the capacity of 1L, and adding deionized water to prepare suspension with the pulp concentration of 6% (namely, the mass fraction of the calcium bentonite is 6%); stirring the suspension in water bath, electrically stirring at 70 deg.C for 15min, dispersing the suspension, and adding 2.0g (5 wt% of calcium bentonite) of analytically pure solid Na 2 CO 3 Continuously stirring for 90min to obtain suspension of sodium bentonite;
(2) Aging the suspension of the sodium bentonite for 2 hours, adding a modifier sodium diethyldithiocarbamate (DDTC), stirring for 4 hours in a constant-temperature water bath at 70 ℃, centrifugally separating to remove supernatant, injecting deionized water into the precipitate obtained by separation to dilute the precipitate to two times, uniformly stirring, centrifugally separating again, injecting water to dilute the precipitate for 3 to 5 times, and washing off the excessive modifier on the surface of the precipitate, wherein the dosage of the modifier is 38mmol;
(3) And (3) putting the washed modified bentonite sample into an oven, drying for 24 hours at 95 ℃, grinding the sample by using an agate container mortar, and sieving the ground sample by using a 200-mesh sieve to prepare a sulfide ore tailing treatment material, which is marked as DDTC-Mt.
(4) Weighing 10g of weathered tailings (CH 2) of a tin polymetallic ore, placing the weathered tailings into a conical flask, and adding 1g of DDTC-Mt and 40ml of simulated acid rain solution with the pH value of 4.5, wherein the reaction temperature is 30 ℃. After shaking for 2h, 4h, 8h, 24h, 48h and 72h respectively at a constant speed (200 rpm) by using a shaker, sampling the mixture in the conical flask, filtering and filtering (0.45 mu m filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Example 9
(1) Weighing 40g of calcium bentonite, placing the calcium bentonite in a glass beaker with the capacity of 1L, and adding deionized water to prepare suspension with the pulp concentration of 6% (namely, the mass fraction of the calcium bentonite is 6%); stirring the suspension in water bath, electrically stirring at 70 deg.C for 15min, dispersing the suspension, and adding 2.0g (5 wt% of calcium bentonite) of analytically pure solid Na 2 CO 3 Continuously stirring for 90min to obtain suspension of sodium bentonite;
(2) Aging the suspension of the sodium bentonite for 2 hours, adding a modifier sodium diethyldithiocarbamate (DDTC), stirring for 4 hours in a constant-temperature water bath at 70 ℃, centrifugally separating to remove supernatant, injecting deionized water into the precipitate obtained by separation to dilute the precipitate to two times, uniformly stirring, centrifugally separating again, injecting water to dilute the precipitate for 3 to 5 times, and washing off the excessive modifier on the surface of the precipitate, wherein the dosage of the modifier is 38mmol;
(3) And (3) putting the washed modified bentonite sample into an oven, drying for 24 hours at 95 ℃, grinding the sample by using an agate ware mortar, and screening the ground sample through a 200-mesh screen to prepare a sulfide ore tailing treatment material, wherein the material is marked as DDTC-Mt.
(4) 10g of a tin multimetal ore tailing deposit (CH 3) was weighed into a conical flask, and 1g of DDTC-Mt and 40ml of a simulated acid rain solution having a pH of 4.5 were added at a reaction temperature of 30 ℃. After shaking for 2h, 4h, 8h, 24h, 48h and 72h respectively at a constant speed (200 rpm) by using a shaker, sampling the mixture in the conical flask, filtering and filtering (0.45 mu m filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by adopting an inductively coupled plasma mass spectrometer.
Comparative example 1
Weighing 10.0g of certain lead-zinc ore tailings (F) and placing the tailings into an erlenmeyer flask, adding 40mL of simulated acid rain solution with the pH value of 4.5 into the erlenmeyer flask, reacting at the temperature of 30 ℃, shaking for 2 hours, 4 hours, 8 hours, 24 hours, 48 hours and 72 hours respectively by using a shaker at a constant speed (200 rpm), sampling the mixture in the erlenmeyer flask, and filtering (with a 0.45-micron filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Weighing 10.0g of certain lead-zinc ore tailings (YD), placing the tailings into a conical flask, adding 40mL of simulated acid rain solution with the pH value of 4.5 into the conical flask, reacting at the temperature of 30 ℃, respectively oscillating for 2 hours, 4 hours, 8 hours, 24 hours, 48 hours and 72 hours at a constant speed (200 rpm) by using an oscillator, sampling the mixture in the conical flask, filtering and filtering (0.45 mu m filter membrane), and obtaining the treated tailings leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by adopting an inductively coupled plasma mass spectrometer.
Weighing 10.0g of fresh tailings (CH 1) of a tin polymetallic ore, placing the fresh tailings into an erlenmeyer flask, adding 40mL of simulated acid rain solution with the pH value of 4.5 into the erlenmeyer flask, reacting at the temperature of 30 ℃, shaking for 2h, 4h, 8h, 24h, 48h and 72h at a constant speed (200 rpm) by using a shaker, sampling the mixture in the erlenmeyer flask, and filtering and leaching (with a 0.45-micron filter membrane) to obtain the treated tailings leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Weighing 10.0g of certain weathered tailings (CH 2) of the tin polymetallic ore, placing the tailings into an erlenmeyer flask, adding 40mL of simulated acid rain solution with the pH value of 4.5 into the erlenmeyer flask, reacting at the temperature of 30 ℃, shaking for 2h, 4h, 8h, 24h, 48h and 72h at a constant speed (200 rpm) by using an oscillator respectively, sampling the mixture in the erlenmeyer flask, and filtering and leaching (with a 0.45-micron filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Weighing 10.0g of a tin polymetallic ore tailing deposit (CH 3) and placing the deposit into an erlenmeyer flask, adding 40mL of simulated acid rain solution with the pH value of 4.5 into the erlenmeyer flask, reacting at the temperature of 30 ℃, shaking for 2h, 4h, 8h, 24h, 48h and 72h at a constant speed (200 rpm) by using an oscillator respectively, sampling the mixture in the erlenmeyer flask, and filtering and leaching (0.45 mu m filter membrane) to obtain the treated tailing leachate. And testing the concentration of the heavy metal ions in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Comparative example 2
Respectively weighing 1.0g of bentonite raw ore and 10g of lead-zinc ore tailings (F) to be uniformly mixed in a conical flask, respectively adding 40ml of simulated acid rain with the pH value of 4.5 into the conical flask, and oscillating at the temperature of 30 ℃. After shaking at a constant speed (200 rpm) for 4h with a shaker, the mixture in the erlenmeyer flask was filtered and filtered (0.45 μm filter membrane) to obtain a treated tailing leachate. And testing the concentrations of the heavy metal ions Zn, mn, as and Pb in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Respectively weighing 1.0g of bentonite raw ore and 10g of lead-zinc ore tailings (YD) to be uniformly mixed in a conical flask, respectively adding 40ml of simulated acid rain with the pH value of 4.5 into the conical flask, and oscillating for 4 hours at the temperature of 30 ℃. After shaking at a constant speed (200 rpm) for 4h with a shaker, the mixture in the erlenmeyer flask was filtered and filtered (0.45 μm filter membrane) to obtain a treated tailing leachate. And testing the concentrations of the heavy metal ions Zn, mn, as and Pb in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Respectively weighing 1.0g of bentonite raw ore and 10g of fresh tailings (CH 1) of a certain tin polymetallic ore in a conical flask, uniformly mixing, respectively adding 40ml of simulated acid rain with the pH value of 4.5 in the conical flask, and oscillating for 4 hours at the temperature of 30 ℃. After shaking at a constant speed (200 rpm) for 4h with a shaker, the mixture in the erlenmeyer flask was filtered and filtered (0.45 μm filter membrane) to obtain a treated tailing leachate. And testing the concentrations of the heavy metal ions Zn, mn, as and Pb in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Respectively weighing 1.0g of bentonite raw ore and 10g of weathered tailings (CH 2) of a certain tin polymetallic ore in a conical flask, uniformly mixing, respectively adding 40ml of simulated acid rain with the pH value of 4.5 in the conical flask, and oscillating for 4 hours at the temperature of 30 ℃. After shaking at a constant speed (200 rpm) for 4h with a shaker, the mixture in the erlenmeyer flask was filtered and filtered (0.45 μm filter membrane) to obtain a treated tailing leachate. And testing the concentrations of the heavy metal ions Zn, mn, as and Pb in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Respectively weighing 1.0g of bentonite raw ore and 10g of a tin polymetallic ore tailing deposit (CH 3) in a conical flask, uniformly mixing, respectively adding 40ml of simulated acid rain with the pH value of 4.5 in the conical flask, and oscillating for 4 hours at the temperature of 30 ℃. After shaking at a constant speed (200 rpm) for 4h with a shaker, the mixture in the erlenmeyer flask was filtered and filtered (0.45 μm filter membrane) to obtain a treated tailing leachate. And testing the concentrations of the heavy metal ions Zn, mn, as and Pb in the treated tailing leachate by using an inductively coupled plasma mass spectrometer.
Test results
X-ray diffraction analysis was performed on the raw material calcium bentonite (Ca-Mt), the sodium bentonite obtained in step (1) of example 1, and the sulfide tailing treatment material obtained in step (3) of examples 1 to 4, respectively, and the XRD patterns were as shown in fig. 1A.
As can be seen from FIG. 1A, the d (001) value of the sodium bentonite (Na-Mt) is 1.24, while the d (001) values of the sulfide ore tailing treatment materials obtained in examples 1 to 4 are all larger than that of sodium bentonite and smaller than that of calcium bentonite (R-Mt), which indicates that all organic complexing agents are successfully intercalated between the bentonite layers. In the four sulfide ore tailing treatment materials, the interlayer spacing between DA-Mt and TEPA-Mt is larger, and the interlayer spacing between DDTC-Mt is smaller.
SEM analysis was performed on the raw material calcium bentonite and the sulfide ore tailings treating material obtained in step (3) of example 1, as shown in fig. 1B and 1C. As can be seen from FIGS. 1B and 1C, the DDTC-Mt surface has a distinct layered structure as compared with Ca-Mt, and these irregularities increase the surface roughness of DDTC-Mt. Furthermore, the DDTC-Mt surface is full of villous lumps, and the surface is stacked more densely compared with the Ca-Mt surface. From the corresponding EDS spectra, it can be seen that DDTC-Mt contains a large amount of C (see FIG. 1D), and DDTC contains a large amount of alkyl, indicating that DDTC has entered into sodium bentonite.
Measuring the concentrations of Zn, mn, as and Pb in the filtrate by adopting an ICP-AES inductively coupled plasma mass spectrometer, and calculating the dissolution amount and the solidification rate of the Zn, mn, as and Pb: five kinds of tailingsThe solidification rate S (%) of the physical material to the heavy metals in the tailings is calculated by the following formula: s (%) = [ (C) 0 -C t )/C 0 ]X100%, wherein C 0 The unit is the cumulative dissolution concentration of the heavy metal in the tailings without adding the tailing treatment material, and the unit is mg/L; c t The unit of the accumulated dissolved concentration of the heavy metal after the tailing treatment material is added and solidified is mg/L. The ratio of the mass of the heavy metal accumulated dissolution of the tailings in the simulated acid rain to the mass m of the tailings is the accumulated dissolution quantity Q, the unit is mg/g, and the calculation formula of the accumulated dissolution quantity is as follows: q = C V/m, wherein C is the cumulative dissolution concentration of the heavy metal and is in mg/L; v was 0.04L and m was 10g.
In example 1, the solidification rate of DDTC-Mt to Zn in tailings is 87.09%, and the dissolution amount is 6.92mg/Kg; the solidification rate of Mn in tailings is 34.49%, and the elution amount is 22.36mg/Kg; the solidification rate of As in the tailings is 87.09%, and the elution amount is 0.80mg/Kg; the solidification rate of Pb in the tailings is 38.31 percent, and the elution amount is 0.77mg/Kg.
In examples 2 to 4, graphs of the cumulative elution amount of heavy metal Zn in tailings after different sulphide ore tailing treatment materials (DA-Mt, TTA-Mt and TEPA-Mt) are solidified for different reaction times (2 h, 4h, 8h, 24h, 48h and 72 h) are respectively shown in FIG. 2A; the graphs of the accumulated elution amounts of the heavy metal Mn in the tailings after different sulfide tailing treatment materials (DA-Mt, TTA-Mt and TEPA-Mt) are solidified for different reaction times (2 h, 4h, 8h, 24h, 48h and 72 h) are respectively shown in FIG. 2B. The graphs of the cumulative elution amounts of heavy metal As in the tailings after different sulfide tailing treatment materials (DA-Mt, TTA-Mt and TEPA-Mt) are solidified for different reaction times (2 h, 4h, 8h, 24h, 48h and 72 h) are respectively shown in FIG. 2C. The graphs of the cumulative elution amounts of heavy metal Pb in the tailings after different sulfide ore tailing treatment materials (DA-Mt, TTA-Mt and TEPA-Mt) are solidified for different reaction times (2 h, 4h, 8h, 24h, 48h and 72 h) are respectively shown in FIG. 2D.
From fig. 2A to fig. 2D, it can be seen that the cumulative elution amount of Zn, mn, as and Pb in the cured tailings of the sulfide ore tailings within 72h is less than 0.02mg/g, the maximum curing rates of DA-Mt, TTA-Mt and TEPA-Mt to Zn can reach 99%, the maximum curing rates to Mn are 57%, 62% and 61%, respectively, the maximum curing rates to As are 88%, 99% and 96%, respectively, and the maximum curing rates to Pb are 63%, 95% and 90%, respectively.
In examples 5 to 9, the cumulative elution amount of the heavy metal Zn after the DDTC-Mt is solidified on different sulfide ore tailings (F, YD, CH1, CH2 and CH 3) for different times (2 h, 4h, 8h, 24h, 48h and 72 h) is plotted as a graph, as shown in FIG. 3A; the accumulated elution amount of the heavy metal Mn after curing of different sulfide ore tailings (F, YD, CH1, CH2 and CH 3) for different time (2 h, 4h, 8h, 24h, 48h and 72 h) by the DDTC-Mt is drawn into a curve graph, as shown in FIG. 3B; the DDTC-Mt is used for drawing a curve chart of the accumulated elution amount of the heavy metal As after different sulfide ore tailings (F, YD, CH1, CH2 and CH 3) are solidified for different times (2 h, 4h, 8h, 24h, 48h and 72 h), and is shown in FIG. 3C; the DDTC-Mt is used for drawing a curve chart of the accumulative elution amount of the heavy metal Pb after curing of different sulfide ore tailings (F, YD, CH1, CH2 and CH 3) for different times (2 h, 4h, 8h, 24h, 48h and 72 h), and is shown in a graph in figure 3D.
3A-3D, the cumulative elution amount of the heavy metals after the DDTC-Mt solidifies different sulfide ore tailings is less than 25mg/Kg within 72 h; when the reaction time is 2h, the curing rates of the DDTC-Mt on Mn in tailings CH1, CH2, CH3 and YD are 89.11%, 72.25%, 53.21% and 77.91%, respectively, the curing rates on Zn in CH1, CH2 and CH3 are 93.89%, 86.62% and 84.79%, respectively, and the curing rate on Pb in YD is 95.43%. As can be seen, the DDTC-Mt has good curing effect on different types of sulfide ore tailings.
The graph of the elution amount of the heavy metal Zn of five tailings to which the tailing treatment material is not added in comparative example 1 after elution for different times (2 h, 4h, 8h, 24h, 48h and 72 h) is shown in fig. 4A, the graph of the elution amount of the heavy metal Mn of five tailings to which the tailing treatment material is not added in comparative example 1 after elution for different times (2 h, 4h, 8h, 24h, 48h and 72 h) is shown in fig. 4B, the graph of the elution amount of the heavy metal As of five tailings to which the tailing treatment material is not added in comparative example 1 after elution for different times (2 h, 4h, 8h, 24h, 48h and 72 h) is shown in fig. 4C, and the graph of the elution amount of the heavy metal Pb of five tailings to which the tailing treatment material is not added in comparative example 1 after elution for different times (2 h, 4h, 8h, 24h, 48h and 72 h) is shown in fig. 4D
As can be seen from FIGS. 4A to 4D, heavy metals Zn, mn, as and Pb are dissolved out to different degrees, and the maximum dissolution amounts of Zn, mn, as and Pb in five kinds of sulfide ore tailings within 72 hours are respectively 63.23mg/Kg,41.11mg/Kg,5.37mg/Kg and 5.51mg/Kg, which exceed the national soil standard.
Comparative example 2 the cumulative elution amounts of heavy metals Zn, mn, as and Pb after 4h of solidification of five tailings from bentonite raw ore were tested, and the results are shown in fig. 5. As can be seen from FIG. 5, the heavy metals Mn and Zn in the CH3 tailings and the F tailings are also dissolved out in a large amount.
Comparing the results, the curing effect of the four sulfide ore tailing treatment materials (DDTC-Mt, DA-Mt, TTA-Mt and TEPA-Mt) on heavy metals in tailings is similar, the release amount of the cured heavy metals is obviously lower than that of the tailings raw ores which are not cured by the tailings treatment materials, and the curing effect of the bentonite raw soil is not good.
Therefore, the bentonite is a good heavy metal solidification material, but the bentonite has limited cation exchange capacity between layers, so that the bentonite has a poor solidification effect on heavy metals in the sulfide tailings. In contrast, the bentonite raw ore is modified by the modifier, so that the cation exchange capacity of the bentonite raw ore is improved, the complexation between the bentonite raw ore and heavy metals is increased, and the solidification effect of the modified bentonite material on the heavy metals in the sulfide ore tailings is greatly improved under specific conditions. After certain lead-zinc mine tailings F are solidified by different sulfide mine tailing treatment materials DA-Mt, TTA-Mt and TEPA-Mt in 4 hours, the elution amounts of Zn, mn, as and Pb are respectively reduced by more than 99%, 51%, 78% and 38%. After being solidified by DDTC-Mt for 4 hours, the elution amounts of Zn, mn, as and Pb in the lead-zinc mine tailings F are respectively reduced from 53.57mg/Kg, 34.13mg/Kg, 3.36mg/Kg and 1.24mg/Kg to 6.92mg/Kg, 22.36mg/Kg, 0.80mg/Kg and 0.77mg/Kg.
It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that the invention is described with reference to exemplary embodiments, but rather the words used therein are words of description and illustration, rather than words of limitation. Modifications may be made to the invention as defined within the scope of the claims and modifications may be made without departing from the scope and spirit of the invention. Although the invention has been described herein with reference to particular means, materials and embodiments, the invention is not intended to be limited to the particulars disclosed herein, but rather extends to all other methods and applications having the same functionality.

Claims (9)

1. A method for treating heavy metal pollution in sulfide ore tailings comprises the following steps:
(1) Preparing calcium bentonite and deionized water into a first suspension with 5-7% of ore pulp concentration, stirring in a constant-temperature water bath at 60-75 ℃ to uniformly disperse, and adding solid Na 2 CO 3 Continuously stirring for 1-2 h to obtain a second suspension; wherein, solid Na 2 CO 3 The dosage is 1-5% of the weight of the calcium bentonite;
(2) Aging the second suspension for 1-2 h, adding a modifier, stirring for 3-4 h in a constant-temperature water bath at 60-75 ℃, centrifuging for 20-30 min, washing and separating the obtained precipitate with deionized water, and repeating the centrifuging and washing for multiple times to obtain modified bentonite; the modifier is at least one of triethylenetetramine, tetraethylenepentamine and sodium diethyldithiocarbamate, and the dosage of the modifier is 95mmol/100g of calcium bentonite;
(3) Drying the modified bentonite at 85-95 ℃, and then grinding and sieving the dried modified bentonite with a 200-mesh sieve to obtain a sulfide ore tailing treatment material;
(4) Mixing the sulfide ore tailings, the treatment material and the simulated acid rain solution at 30-40 ℃, oscillating for 1-72 hours at a constant speed, and filtering and leaching the mixture to obtain a treated tailings leachate, wherein the ratio of the sulfide ore tailings, the treatment material and the simulated acid rain solution is 10g: 0.5-2 g: 30-50 mL.
2. The method according to claim 1, wherein in the step (1), the ore pulp concentration of the first suspension is 6%, and the first suspension is stirred in a constant-temperature water bath at 70 ℃ for 10-20 min.
3. The method of claim 1, wherein in step (1), solid Na is added 2 CO 3 Then stirring is continued for 90min.
4. The method according to claim 1, wherein in the step (2), the temperature of the thermostatic water bath is 70 ℃, and the stirring time is 4h.
5. The method of claim 1, wherein in step (2), the centrifuging and washing are performed a plurality of times by: after the supernatant liquid is removed by centrifugal separation, deionized water is injected into the precipitate obtained by separation to dilute the precipitate to two times, the mixture is stirred evenly, and the centrifugal separation and the water injection dilution are repeated for 3 to 5 times.
6. The method according to claim 1, wherein in the step (3), the drying time is 24 to 48 hours.
7. The method of claim 1, wherein in step (4), the sulfide tailings are mixed with the remediation material and simulated acid rain solution at 30 ℃.
8. The method of claim 1, wherein in step (4), the constant oscillation speed is 200rpm.
9. The method of claim 1, wherein in step (4), the ratio of the sulfide tailings, the remediation material to the simulated acid rain solution is 10g:1g:40mL.
CN202010922047.9A 2020-09-04 2020-09-04 Method for treating heavy metal pollution in sulfide ore tailings Active CN111992258B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010922047.9A CN111992258B (en) 2020-09-04 2020-09-04 Method for treating heavy metal pollution in sulfide ore tailings

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010922047.9A CN111992258B (en) 2020-09-04 2020-09-04 Method for treating heavy metal pollution in sulfide ore tailings

Publications (2)

Publication Number Publication Date
CN111992258A CN111992258A (en) 2020-11-27
CN111992258B true CN111992258B (en) 2023-03-21

Family

ID=73470106

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010922047.9A Active CN111992258B (en) 2020-09-04 2020-09-04 Method for treating heavy metal pollution in sulfide ore tailings

Country Status (1)

Country Link
CN (1) CN111992258B (en)

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103464113A (en) * 2013-09-22 2013-12-25 广西大学 Composite modified bentonite, as well as preparation method and application thereof
CN106367076A (en) * 2016-08-29 2017-02-01 广西博世科环保科技股份有限公司 Preparation method of organic-inorganic composite heavy metal contaminated soil passivator

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2983186A1 (en) * 2015-05-21 2016-11-24 Csir Water treatment using cryptocrystalline magnesite

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103464113A (en) * 2013-09-22 2013-12-25 广西大学 Composite modified bentonite, as well as preparation method and application thereof
CN106367076A (en) * 2016-08-29 2017-02-01 广西博世科环保科技股份有限公司 Preparation method of organic-inorganic composite heavy metal contaminated soil passivator

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Adsorption of heavy metal and organic pollutant by organo‑montmorillonites in binary‑component system;Guifang Wang et al.;《Journal of Porous Materials》;20200622;第27卷;第1-8页 *

Also Published As

Publication number Publication date
CN111992258A (en) 2020-11-27

Similar Documents

Publication Publication Date Title
Rinklebe et al. Redox-induced mobilization of Ag, Sb, Sn, and Tl in the dissolved, colloidal and solid phase of a biochar-treated and un-treated mining soil
Mohan et al. Single, binary and multi-component adsorption of copper and cadmium from aqueous solutions on Kraft lignin—a biosorbent
Zhang et al. Efficiency and mechanisms of Cd removal from aqueous solution by biochar derived from water hyacinth (Eichornia crassipes)
CN100402141C (en) Preparation method of modified turf adsorbent
CN105219393A (en) The preparation method of lignin modification heavy metal deactivator
Namasivayam et al. Waste biogas residual slurry as an adsorbent for the removal of Pb (II) from aqueous solution and radiator manufacturing industry wastewater
CN111570494B (en) Heavy metal contaminated soil remediation method
Gomes et al. Immobilization of lead by amendments in a mine-waste impacted soil: Assessing Pb retention with desorption kinetic, sequential extraction and XANES spectroscopy
CN113019708A (en) Oxidation flotation separation process for copper-molybdenum bulk concentrate
CN113996265A (en) Preparation method and application of iron-modified phosphogypsum
CN113368875A (en) Method for preparing ferroferric sulfide oxide complex by solid raw material mechanochemical method and application thereof
CN113649410B (en) Process for repairing heavy metal pollution of soil by using nano repairing material
Wang et al. Effect of a low-cost and highly efficient passivator synthesized by alkali-fused fly ash and swine manure on the leachability of heavy metals in a multi-metal contaminated soil
CN114774130A (en) Modified clay mineral for repairing arsenic-lead-antimony composite contaminated soil and preparation method and application thereof
CN111992258B (en) Method for treating heavy metal pollution in sulfide ore tailings
CN111228711B (en) Method for stabilizing and curing mercury-containing waste salt slag by using petrochemical waste alkali slag
US20240157415A1 (en) Process for producing heavy-metal-mediated biochar complex cured by using silicate
Bennour Influence of pH and ionic strength on the adsorption of copper and zinc in bentonite clay
KR102456298B1 (en) Preparing method of hydrochar stabilizers based on wood waste comprising iron nanoparticles and Stabilization method for contaminated soil comprising arsenic and cation mixed using thereof
CN116376555B (en) White mica-based calcium-magnesium loaded heavy metal passivator and preparation method and application thereof
Wang et al. Utilizing different types of biomass materials to modify steel slag for the preparation of composite materials used in the adsorption and solidification of Pb in solutions and soil
CN115415295B (en) Method and kit for stabilizing vanadium in soil
Wibowo et al. Low-cost modified reactor to produce biochar and clamshell as alternative materials from acid mine drainage problem solving
Ogar et al. Phytostabilization of uranium-containing shale residues using Hieracium pilosella
CN112852432A (en) Stabilizer prepared from organic waste and using method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant