Leaching test method and analysis method for research on heavy metal environmental pollution of metal mine

Abstract

The invention provides a leaching test method and an analysis method for researching heavy metal environmental pollution of a metal mine, and belongs to the technical field of ore analysis. The leaching test method for studying the heavy metal environmental pollution of the metal mine, provided by the invention, comprises the following steps: filling a leaching column with a metal mine sample; the particle size of the metal mine sample is 3-5mm; leaching the metal mine sample in the leaching column by using a leaching solution, and collecting to obtain a leaching solution; the leaching time is more than 1000 minutes; the leaching speed is 5 to 6 mL / min. According to the leaching method for comprehensive evaluation of mine environmental pollution, factors including leaching samples, particle sizes, leaching time, leaching solution pH values, leaching speeds and the like are comprehensively considered, the scheme is more scientific, comprehensive and objective, practical operation is achieved, the leaching test process is simple and clear, and the leaching method is suitable for research of metal mine environmental pollution problems.

Description

Technical Field

[0001] The invention belongs to the technical field of ore analysis, and in particular relates to a leaching test method and an analysis method for studying heavy metal environmental pollution in metal mines. Background Art

[0002] During the mining process, metal mines are accompanied by the emergence of a large amount of solid waste, which is one of the main sources of heavy metal pollution in the environment. The solid waste of metal mines contains a variety of toxic and harmful substances, such as heavy metal elements and some radioactive elements, which are the main primary and secondary pollution sources that cause the pollution and acidification of mine water bodies and make the water bodies contain a large amount of metals and heavy metal ions. As the amount of mine waste rock and tailings increases year by year, the stockpile is getting bigger and bigger. During the rainy season, a large amount of solid waste from the stockpile is lost, causing the blockage of streams and rivers, causing serious water pollution. At the same time, the solid waste of metal mines and other harmful elements enter the environment through rainwater leaching, weathering and oxidation and other surface effects, destroying the ecosystem and threatening the quality of the mine environment.

[0003] In order to solve the environmental pollution problem of metal mines, it is necessary to conduct a detailed investigation of the mines, mainly involving: ore type and content analysis, waste rock and slag detection, mine water monitoring, surrounding soil pollution investigation, crop pollution investigation, groundwater and surface water and other hydrogeological investigations, etc., and finally conduct a comprehensive analysis and judgment based on the investigation results of these problem factors. In the existing technology, leaching is mostly used for these waste rocks and slag to deeply study the pollution problems caused by mine solid waste to the environment. However, the relevant results and data obtained from the current leaching method test have great limitations, the comprehensive factors are not fully considered, and the operability is poor, making the results difficult to control, and there are few leaching tests for metal mine environmental pollution. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a leaching test method and an analysis method for heavy metal environmental pollution research in metal mines. The test results obtained by the method provided by the present invention are highly accurate and comprehensive.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0006] The present invention provides a leaching test method for studying heavy metal environmental pollution in metal mines, comprising the following steps:

[0007] Filling the metal mine sample into the leaching column; the particle size of the metal mine sample is 3 to 5 mm;

[0008] The metal mine sample in the leaching column is leached with a leaching solution to collect the leaching solution; the leaching time is more than 1000 minutes; and the leaching speed is 5 to 6 mL / min.

[0009] Preferably, the metal mine samples in the leaching column are leached using a leaching solution: the metal mine samples in the leaching column are leached using leaching solutions with different pH values; the leaching solutions with different pH values ​​are water and acidic leaching solutions; the pH value of the acidic leaching solution is the pH value of the water quality around the collection site of the metal mine samples.

[0010] Preferably, before filling the metal mine sample into the leaching column, the method further includes: applying vaseline on the inner wall of the leaching column.

[0011] Preferably, the leaching column is also filled with quartz sand; the filling material of the leaching column includes first quartz sand, metal mine sample and second quartz sand from bottom to top.

[0012] Preferably, the filling height of the first quartz sand is 8 to 12 cm, the filling height of the metal mine sample is 18 to 22 cm, and the filling height of the second quartz sand is 8 to 12 cm.

[0013] Preferably, the particle size of the first quartz sand is 1 to 3 mm, and the particle size of the second quartz sand is 1 to 3 mm.

[0014] Preferably, absorbent cotton is also installed at the bottom of the leaching column, and a silica gel sand net is laid below the absorbent cotton.

[0015] Preferably, the elution further comprises infiltrating the metal mine sample before infiltrating, and during the infiltration, the level of the elution solution is 3 to 6 cm higher than the top of the filling in the elution column.

[0016] Preferably, the infiltration is performed 2 to 4 times.

[0017] The present invention also provides an analytical method for studying heavy metal environmental pollution in metal mines, comprising the following steps:

[0018] Sample collection and processing to obtain metal mine samples;

[0019] Leaching the metal mine sample according to the leaching test method described in the above technical solution, and collecting the leaching liquid;

[0020] The leaching liquid is tested by inductively coupled plasma mass spectrometry to obtain the content of each metal element, which is recorded as the first test result;

[0021] Conducting a leaching toxicity test on the metal mine sample to measure the content of each metal element, which is recorded as a second test result;

[0022] Conducting a corrosion identification test on the metal mine sample to measure the content of each metal element, which is recorded as the third test result;

[0023] Combined with the first test result, the second test result and the third test result, a comprehensive analysis of the heavy metal environmental pollution in metal mines is conducted.

[0024] The present invention provides a leaching test method for the study of heavy metal environmental pollution in metal mines, comprising the following steps: filling a metal mine sample into a leaching column; the particle size of the metal mine sample is 3 to 5 mm; using a leaching solution to leach the metal mine sample in the leaching column, and collecting the leached solution; the pH of the leaching solution is 6 to 7; the leaching time is more than 1000 minutes; the leaching speed is 5 to 6 mL / min. The present invention designs a leaching method for comprehensive assessment of mine environmental pollution. By comprehensively considering factors including leaching samples, particle size, leaching time, leaching speed, etc., the scheme is more scientific, comprehensive, objective, and practical, and a set of leaching test processes and methods are established. The process of the method is simple and clear, and is suitable for the study of metal mine environmental pollution problems.

[0025] Furthermore, the method of first evenly applying vaseline on the leaching column and selecting an appropriate sample particle size is adopted to effectively avoid the dominant flow in the leaching process, and turbulence will not occur; neutral and weakly acidic leaching solutions are considered, especially considering that metal mines are prone to form acidic solutions under long-term rain immersion, and water and weakly acidic water (that is, combined with the pH value of the water quality around the sample collection site) are used as leaching solutions for synchronous comparative research, and the results obtained are more scientific and reasonable; the filling of the leaching column of the present invention is more scientific, reasonable and practical.

[0026] After the leaching liquid is obtained by the leaching test method of the present invention, the pH value, the inorganic heavy metal elements (Cu, Pb, Zn, Ni, Cd, Cr, V, Ti, Mn, Al, As, Hg, Se, Fe) of the leaching liquid can be obtained by testing the leaching liquid. 2+ , Fe 3+ 、F - etc.) and other pollutant indicators. Special mines can add characteristic pollutant detection indicators according to actual conditions. After obtaining the test results, the present invention can be further combined with total volume analysis and toxicity leaching test for comprehensive evaluation. When applied in the process of mine environmental pollution investigation, more reasonable, scientific and objective conclusions can be obtained, which will then provide scientific guidance for the next step of mine environmental restoration.

[0027] The method provided by the present invention studies the influence of different leaching solvents and leaching time on samples of different particle sizes, and can comprehensively evaluate the environmental pollution of mines by combining the test results of ore types and waste rock / slag. And the leaching test method is highly operable by using a self-made leaching test device. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0029] Figure 1 This is a flow chart of the method for studying heavy metal environmental pollution in metal mines according to the present invention;

[0030] Figure 2 This is the leaching result diagram of the Y2 sample in Example 1 in the pH=7 leaching solution (water);

[0031] Figure 3 This is the leaching result diagram of the Y3 sample in Example 3 in the pH=7 leaching solution (water);

[0032] Figure 4 This is the leaching result diagram of the Y2 sample in Example 2 in the pH=6 leaching solution (weakly acidic water);

[0033] Figure 5 This is the leaching result diagram of the Y3 sample in Example 4 in the pH=6 leaching solution (weakly acidic water). DETAILED DESCRIPTION

[0034] The present invention provides a leaching test method for studying heavy metal environmental pollution in metal mines, comprising the following steps:

[0035] Filling the metal mine sample into the leaching column; the particle size of the metal mine sample is 3 to 5 mm;

[0036] The metal mine sample in the leaching column is leached with a leaching solution to collect the leaching solution; the leaching time is more than 1000 minutes; and the leaching speed is 5 to 6 mL / min.

[0037] In the present invention, unless otherwise specified, the raw materials involved are commercially available products well known in the art.

[0038] The present invention fills the metal mine sample into the leaching column.

[0039] The present invention preferably obtains metal mine samples through sample collection and processing.

[0040] In the present invention, the metal mine samples preferably include waste rock samples and / or slag heap samples. In the present invention, the collection of the waste rock samples preferably includes: selecting 3 to 5 typical mine waste rock / bedrock samples, and selecting samples of different depths and different positions that can represent the mine matrix at no less than 2 kg for each sample collection. In the present invention, the collection of the slag heap samples preferably includes: selecting 3 to 5 samples, and when sampling, first peel off a layer of the surface, and then take 1 sample every 50 centimeters, and each sample is no less than 2 kg.

[0041] The present invention preferably processes the collected waste rock samples and / or waste slag pile samples to obtain metal mine samples. In the present invention, the processing preferably includes crushing and grinding in sequence to obtain metal mine samples. In the present invention, the particle size of the crushed sample is preferably 1 to 2 cm. In the present invention, the particle size of the metal mine sample is preferably 3 to 5 mm. The present invention has no special requirements for the crushing and grinding methods, and the commonly used technical means of the present invention can be used. In a specific embodiment of the present invention, the crushing preferably uses a crusher or disc mill with a corundum / agate liner, and the grinding preferably uses an agate grinder. Grinding the sample to a suitable particle size can more reasonably reflect the natural leaching effect. If the particle size is too large, it cannot be leached evenly, and it is difficult to fill the leaching column evenly; if the particle size is too fine, the leaching speed is too slow, and it cannot even pass through the leaching column without pressurization.

[0042] In the present invention, the leaching column preferably uses the leaching simulation test flow control device described in CN217639057U.

[0043] In the present invention, before filling the metal mine sample into the leaching column, the method preferably further includes: applying vaseline on the inner wall of the leaching column. Applying vaseline before filling the sample can effectively avoid the dominant flow in the leaching process, and no turbulence phenomenon will occur.

[0044] In the present invention, the leaching column is preferably also filled with quartz sand; the filling material of the leaching column preferably includes first quartz sand, metal mine sample and second quartz sand from bottom to top. In the present invention, the filling height of the first quartz sand is preferably 8-12 cm, more preferably 9-11 cm; the filling height of the metal mine sample is preferably 18-22 cm, more preferably 19-21 cm; the filling height of the second quartz sand is preferably 8-12 cm, more preferably 9-11 cm. In a specific embodiment of the present invention, the filling material in the leaching column includes first quartz sand with a filling height of 10 cm, metal mine sample with a filling height of 20 cm and second quartz sand with a filling height of 10 cm from bottom to top.

[0045] In the present invention, the first quartz sand and the second quartz sand are preferably pre-treated before filling, and the pre-treatment preferably includes washing and drying. In the present invention, the washing is preferably carried out with water. The present invention has no special requirements for the drying method, and the commonly used technical means in the art can be used, such as drying, air-drying, etc.

[0046] In the present invention, the bottom of the leaching column is preferably equipped with absorbent cotton, and a silica sand net is laid below the absorbent cotton. In the present invention, the absorbent cotton is preferably located below the first quartz sand.

[0047] In the present invention, the particle size of the first quartz sand is preferably 1-3 mm, more preferably 2 mm; the particle size of the second quartz sand is preferably 1-3 mm, more preferably 2 mm. The present invention uses quartz sand as the water distribution layer to avoid metal element pollution and matches the background matrix of metal mine pollution research.

[0048] In the present invention, the leaching column is preferably filled by shaking while filling, which makes the filling material filled evenly and densely, and prevents the generation of dominant flow.

[0049] After the metal mine sample is filled into the leaching column, the present invention utilizes the leaching solution to leach the metal mine sample in the leaching column, and collects the leaching liquid.

[0050] In the present invention, the use of the leaching solution to leach the metal mine samples in the leaching column is: using leaching solutions with different pH values ​​to leach the metal mine samples in the leaching column respectively. In the present invention, the leaching solutions with different pH values ​​are preferably water and acidic leaching solutions respectively. The pH value of the acidic leaching solution is preferably the pH value of the water quality around the collection site of the metal mine samples, and in a specific embodiment of the present invention, the pH value is 6.

[0051] In the present invention, the leaching preferably includes infiltration of the metal mine sample before the leaching, and during the infiltration, the level of the leaching solution is preferably 3 to 6 cm higher than the top of the filling in the leaching column, and more preferably 5 cm. In the present invention, the number of infiltrations is preferably 2 to 4 times, and more preferably 3 times.

[0052] Specifically, the infiltration preferably includes: adding leaching solution to the filled leaching column so that the leaching solution completely infiltrates the filler, and stopping adding the leaching solution when the horizontal liquid level reaches the target height from the top of the filler, waiting for solution to flow out of the outlet below the column until the horizontal liquid level of the leaching solution is flush with the top of the filler, continuing to add the leaching solution until the liquid level is a certain distance above the top of the filler, and repeating the above operation 2 to 4 times.

[0053] In the present invention, the leaching rate is 5 to 6 mL / min. The leaching rate of the leaching solution is adjusted so that the water inlet rate matches the water outlet rate to ensure that the liquid level maintains a constant height. If the flow rate is too fast, the leaching solution may accumulate and soak, or dry up due to the rapid drop of the leaching solution, that is, there is no continuous leaching. If the flow rate is too slow, the leaching time will be too long and the test cannot be carried out normally. In short, by controlling the flow rate and flow rate, try to achieve simulation conditions based on leaching that is closer to natural conditions.

[0054] In the present invention, the leaching time is more than 1000 minutes, preferably 1000 minutes to 35 hours. In the present invention, the leaching time is counted from the beginning of receiving the outlet solution (excluding the time of infiltration), and the leaching solution is replaced and collected every 0.5 hours.

[0055] In the present invention, the leaching liquid is preferably tested for relevant indicators using methods such as inductively coupled plasma spectroscopy, mass spectrometry, and atomic fluorescence spectrometry.

[0056] The present invention also provides an analytical method for studying heavy metal environmental pollution in metal mines, comprising the following steps:

[0057] Sample collection and processing to obtain metal mine samples;

[0058] Leaching the metal mine sample according to the leaching test method described in the above technical solution, and collecting the leaching liquid;

[0059] The leaching liquid is tested by inductively coupled plasma mass spectrometry to obtain the content of each metal element, which is recorded as the first test result;

[0060] Conducting a leaching toxicity test on the metal mine sample to measure the content of each metal element, which is recorded as a second test result;

[0061] Conducting a corrosion identification test on the metal mine sample to measure the content of each metal element, which is recorded as the third test result;

[0062] Combined with the first test result, the second test result and the third test result, a comprehensive analysis of the heavy metal environmental pollution in metal mines is conducted.

[0063] In the present invention, the steps of sample collection and processing have been discussed above and will not be repeated here.

[0064] In the present invention, the leachate is detected by inductively coupled plasma mass spectrometry. Preferably, the metal elements are determined by inductively coupled plasma mass spectrometry according to HJ766-2015 solid waste and DZ / T 0279-2016 regional geochemical sample analysis method.

[0065] In the present invention, the leaching toxicity test is preferably carried out using the HJ 557-2010 solid waste leaching toxicity leaching method (horizontal oscillation method) and the HJ 299-2007 solid waste sulfuric acid and nitric acid solution method.

[0066] In the present invention, the corrosiveness identification test preferably adopts GB 5085.1-2007 Hazardous Waste Identification Standard for corrosiveness identification.

[0067] The method provided by the present invention is based on the actual research work of the mine environmental pollution investigation, and designs a leaching test with comprehensive consideration of multiple factors. The purpose is to simulate the leaching and immersion of abandoned slag piles in rainwater, groundwater, etc. under natural conditions, and the physical and chemical changes of substances (including the dissolution of heavy metal ions, the hydrolysis and oxidation process of variable-valence metal ions, the change of hydrogen ion concentration, and the color presentation of color-causing ions, etc.), thereby estimating the heavy metal pollution in the area, finding the generation mechanism and influencing factors of sulfonic water and acidic water, and seeking effective measures to control the impact of polluted water bodies in the area on the surrounding water quality and soil.

[0068] The samples were tested for the total content of the same indicators using HJ 766-2015 Determination of Metal Elements in Solid Waste and Inductively Coupled Plasma Mass Spectrometry; GB 5085.1-2007 Identification Standard for Hazardous Wastes was used for corrosive identification; HJ 557-2010 Solid Waste Leaching Toxicity Leaching Method (Horizontal Oscillation Method) and HJ 299-2007 Solid Waste Sulfuric Acid and Nitric Acid Solution Method were used for leaching toxicity leaching tests, and auxiliary analysis was performed.

[0069] The present invention combines the detection results obtained from the leaching liquid with the auxiliary analysis results for comprehensive evaluation. When applied in the process of mine environmental pollution investigation, more reasonable, scientific and objective conclusions can be obtained, which in turn provides scientific guidance for the next step of mine environmental restoration.

[0070] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described in conjunction with specific embodiments below. The described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Any modification, equivalent replacement, improvement, etc. made to the implementation methods of the present invention based on the technical essence and general principles of the present invention without creative work should be within the scope of protection of the present invention.

[0071] Figure 1 This is a flow chart of the method for studying heavy metal environmental pollution in metal mines according to the present invention, referring to Figure 1 Conduct the following research:

[0072] Example 1

[0073] Ore Y2 sample was collected from the Chenjiagou ore slag pile, the sample was placed in a crusher with an agate liner for grinding, and then processed into 3-5 mm by an agate grinder for use.

[0074] Wash 2mm quartz sand with deionized water and dry it. Put the treated quartz sand into the leaching column with the inner wall evenly coated with vaseline, a layer of absorbent cotton at the bottom, and a silica sand net under the absorbent cotton. The filling height is 10cm, and then the treated sample is filled 20cm high above the quartz stone, and the treated quartz sand is filled 20cm high above the sample.

[0075] Slowly add leaching solution water to the installed leaching column to make the leaching column filling completely infiltrated, and ensure that the leaching solution level is 5 cm higher than the top of the filling, stop adding water, wait for the solution to flow out of the outlet of the column, and when the water level drops to the same level as the top of the filling, continue to add water until the liquid level is 5 cm higher than the top of the filling, repeat the above operation twice, adjust the flow rate of the water outlet and the flow rate of the water inlet to 5-6mL / min, place the receiving bottle under the leaching column, start to receive the outlet solution, replace the receiving bottle every half an hour, and shake the leaching solution collected in the receiving bottle as a set of test liquid. According to HJ 766-2015 solid waste and DZ / T 0279-2016 regional geochemical sample analysis method, the metal elements were determined by inductively coupled plasma mass spectrometry. The results are summarized in Table 1-1 and Table 1-2.

[0076] The particle size of the Y2 sample is 3 to 5 mm. The filtrate collected every 30 minutes is a group of samples. After shaking, they are recorded as Y2-1, Y2-2, ... Y2-19, Y2-20, for a total of 20 groups of filtrates.

[0077] Table 1-1 Leaching results of sample Y2 at pH = 7

[0078]

[0079] Table 1-2 Leaching results of sample Y2 at pH = 7

[0080]

[0081]

[0082] Example 2

[0083] The leaching solution was replaced with a weakly acidic solution (acidified with dilute sulfuric acid) with a pH of 6. Other conditions were the same as those in Example 1. The metal elements were determined. The results were summarized in Tables 2-1 and 2-2.

[0084] The particle size of the Y2 sample is 3 to 5 mm. The leaching liquid collected every 30 minutes is a group of samples. After shaking, they are recorded as Y2-1, Y2-2, ... Y2-17, Y2-18, for a total of 18 groups of filtrates.

[0085] Table 2-1 Leaching results of sample Y2 at pH = 6

[0086]

[0087]

[0088] Table 2-2 Leaching results of sample Y2 at pH = 6

[0089]

[0090]

[0091] Example 3

[0092] The sample was replaced with the Damogou Gounao slag Y3 sample. Other conditions were the same as in Example 1. 20 groups of test solutions were collected. The metal elements were determined. The results were summarized in Table 3-1 and Table 3-2.

[0093] The particle size of the Y3 sample is 3 to 5 mm. The filtrate collected every 30 minutes is a group of samples. After shaking, they are recorded as Y3-1, Y3-2, ... Y3-19, Y3-20, for a total of 20 groups of filtrates.

[0094] Table 3-1 Leaching results of sample Y3 at pH = 7

[0095]

[0096]

[0097] Table 3-2 Leaching results of sample Y3 at pH = 7

[0098]

[0099] Example 4

[0100] The leaching solution was replaced with a weakly acidic solution (acidified with dilute sulfuric acid) with a pH of 6. Other conditions were the same as those in Example 3. 18 groups of test solutions were collected. Metal elements were determined. The results were summarized in Table 4-1 and Table 4-2.

[0101] The particle size of the Y3 sample is 3 to 5 mm. The leaching liquid collected every 30 minutes is a group of samples. After shaking, they are recorded as Y3-1, Y3-2, ... Y3-17, Y3-18, for a total of 18 groups of filtrates.

[0102] Table 4-1 Leaching results of sample Y3 at pH = 6

[0103]

[0104]

[0105] Table 4-2 Leaching results of sample Y3 at pH = 6

[0106]

[0107]

[0108] Auxiliary test 1

[0109] According to GB 5085.1-2007 hazardous waste identification standard, the corrosiveness of Example 1 was identified. The metal elements were determined. The results are summarized in Table 5-1 and Table 5-2.

[0110] Auxiliary Test 2

[0111] According to GB 5085.1-2007 hazardous waste identification standard, the corrosiveness of Example 3 was identified. The metal elements were determined. The results are summarized in Table 5-1 and Table 5-2.

[0112] Table 5-1 Total amount of elements in Y2 and Y3

[0113]

[0114] Table 5-2 Total amount of elements in Y2 and Y3

[0115]

[0116] It can be seen from Table 5-1 and Table 5-2 that the heavy metal elements such as Ni, Co, Cu, Zn, and Cd in Y2 and Y3 are equivalent and the content is relatively high.

[0117] Auxiliary test 3

[0118] According to HJ 557-2010 Solid Waste Leaching Toxicity Leaching Method (Horizontal Oscillation Method), Example 1 was identified. Metal elements were determined. The results are summarized in Table 6-1 and Table 6-2. According to the standard method flow, a blank test was performed simultaneously.

[0119] Auxiliary Test 4

[0120] According to HJ 557-2010 Solid Waste Leaching Toxicity Leaching Method (Horizontal Oscillation Method), Example 3 was identified. Metal elements were determined. The results are summarized in Table 6-1 and Table 6-2. According to the standard method flow, a blank test was performed simultaneously.

[0121] Table 6-1 Results of leaching toxicity test of solid waste (horizontal oscillation method)

[0122]

[0123] Table 6-2 Results of leaching toxicity test of solid waste (horizontal oscillation method)

[0124]

[0125] From Table 6-1 and Table 6-2, it can be seen that the heavy metal content in Y2 and Y3 is relatively high, and the pH value of their leaching solution is relatively low, about 3 to 4. According to the corrosiveness identification of GB 5085.1-2007 Hazardous Waste Identification Standard, the samples are not corrosive.

[0126] Auxiliary Test 5

[0127] HJ 299-2007 Solid Waste Sulfuric Acid and Nitric Acid Solution Method Leaching Toxicity Leaching Test (Tumbling Oscillation Method). Example 1 was identified. Metal elements were determined. The results were summarized in Table 7-1 and Table 7-2. A blank test was performed simultaneously according to the standard method flow.

[0128] Auxiliary Test 6

[0129] HJ 299-2007 Solid Waste Sulfuric Acid and Nitric Acid Solution Method Leaching Toxicity Leaching Test (Tumbling Oscillation Method). Example 3 was identified. Metal elements were determined. The results were summarized in Table 7-1 and Table 7-2. A blank test was performed simultaneously according to the standard method flow.

[0130] Table 7-1 Results of leaching toxicity test of solid waste (tumbling oscillation method)

[0131]

[0132]

[0133] Table 7-2 Results of leaching toxicity test of solid waste (tumbling oscillation method)

[0134]

[0135] Comparing with the national standard GB 5085.3-2007 Hazardous Waste Identification Standard Leaching Toxicity Identification, combined with the data in Table 7-1 and Table 7-2, it is found that although the heavy metal content is high, it does not exceed the standard and is not a hazardous waste. However, compared with the comprehensive sewage discharge standard GB 8978-1996 Comprehensive sewage discharge standard, the Cu and Ni elements are exceeded.

[0136] Two leaching solutions with different acidity (pH 7.00 and 6.00) were used to wash the two ore samples Y2 and Y3 respectively. The results were summarized in Table 1-1, Table 1-2, Table 2-1, Table 2-2, Table 3-1, Table 3-2, Table 4-1 and Table 4-2, and plotted as Figures 2 to 5 . By analyzing the obtained results, we can know that:

[0137] (1) The more acidic the leaching solution is, the higher the metal ion content leached out. The leaching solution with a pH of 6.00 has a high metal dissolution rate.

[0138] (2) The content of metal elements Mn, Ni, Zn, Al, Fe, and Cu in the leachate solution is much higher than that of elements such as Se, Cd, Pb, Cr, and Ti, which is basically consistent with the relationship between the total element content in the sample.

[0139] (3) The contents of Hg and As are very low. Compared with the total content of the elements, it can be seen that the Hg and As background in the study area is low.

[0140] (4) From the perspective of the pH value of the leaching solution, the pH values ​​of samples Y2 and Y3 were between 3 and 4 from the very beginning of leaching, which was acidic. This was related to the samples themselves, indicating that the anthracite ore and some of its slag in the study area were prone to acidity in the presence of water.

[0141] (5) The metal elements in the leached filtrate were compared with the national standards GB 5085.3-2007 Hazardous Waste Identification Standard and GB 8978-1996 Wastewater Comprehensive Discharge Standard. It was found that although the concentrations of some heavy metal elements were high, the elements specified in the standards did not exceed the standard.

[0142] (6) From the leaching trend diagram and results, it can be seen that the dissolution rate of most metal elements tends to be stable after the leaching solution volume reaches 1000 min.

[0143] The method provided by the present invention considers more and more comprehensive factors, and controls the elution environment to be consistent with the local geological environment during the elution process, and combines the measured elution results with the total amount test and the leaching toxicity identification method results for analysis, so that the test results are more comprehensive and the results are highly accurate.

[0144] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A leaching test method for heavy metal environmental pollution research in metal mines, characterized in that: The following steps are involved: Filling the metal mine sample into the leaching column; the particle size of the metal mine sample is 3 to 5 mm; The metal mine sample in the leaching column is leached with a leaching solution to collect the leaching solution; the leaching time is more than 1000 minutes; and the leaching speed is 5 to 6 mL / min.

2. The leaching test method according to claim 1, characterized in that: The method of using the leaching solution to leach the metal mine samples in the leaching column includes: using leaching solutions with different pH values ​​to leach the metal mine samples in the leaching column respectively; the leaching solutions with different pH values ​​are water and acidic leaching solutions respectively; the pH value of the acidic leaching solution is the pH value of the water quality around the collection site of the metal mine samples.

3. The leaching test method according to claim 1, characterized in that: Before filling the metal mine sample into the leaching column, the method further includes: applying vaseline on the inner wall of the leaching column.

4. The leaching test method according to claim 1, characterized in that: The leaching column is also filled with quartz sand; the fillings of the leaching column include first quartz sand, metal mine sample and second quartz sand from bottom to top.

5. The leaching test method according to claim 4, characterized in that: The filling height of the first quartz sand is 8 to 12 cm, the filling height of the metal mine sample is 18 to 22 cm, and the filling height of the second quartz sand is 8 to 12 cm.

6. The leaching test method according to claim 4 or 5, characterized in that: The particle size of the first quartz sand is 1 to 3 mm, and the particle size of the second quartz sand is 1 to 3 mm.

7. The leaching test method according to claim 1, 3 or 4, characterized in that: The bottom of the leaching column is also equipped with absorbent cotton, and a silica gel sand net is laid below the absorbent cotton.

8. The leaching test method according to claim 1 or 2, characterized in that: The method also includes infiltrating the metal mine sample before eluting. During the infiltration, the level of the eluting solution is 3 to 6 cm higher than the top of the filling in the eluting column.

9. The leaching test method according to claim 8, characterized in that: The number of times of infiltration is 2 to 4 times.

10. An analytical method for studying heavy metal environmental pollution in metal mines, characterized in that: The following steps are involved: Sample collection and processing to obtain metal mine samples; Leaching the metal mine sample according to the leaching test method according to any one of claims 1 to 9, and collecting the leaching liquid; The leaching liquid is tested by inductively coupled plasma mass spectrometry to obtain the content of each metal element, which is recorded as the first test result; Conducting a leaching toxicity test on the metal mine sample to measure the content of each metal element, which is recorded as a second test result; Conducting a corrosion identification test on the metal mine sample to measure the content of each metal element, which is recorded as the third test result; Combined with the first test result, the second test result and the third test result, a comprehensive analysis of the heavy metal environmental pollution in metal mines is conducted.

Images