Method and equipment for resource utilization and harmless treatment of manganese slag

Abstract

The present invention discloses a method and apparatus for resource utilization and harmless treatment of manganese slag. The method comprises washing the manganese slag with water to separate ammonium sulfate and manganese sulfate, electrolyzing the manganese sulfate to obtain electrolytic manganese, and then harmlessly treating the waste residue obtained by washing and filtering the slag with the slag washing water. This completes the recovery of divalent manganese and ammonium sulfate in the manganese slag and the harmless treatment of the waste residue. The harmlessly treated waste residue can be used to produce environmentally friendly bricks or as a cement admixture, thereby achieving resource recycling and economic circulation. The method of the present invention has low production cost, and the recovery rate of the soluble manganese and ammonium sulfate obtained by separation and recovery can reach over 80%. The treated manganese slag meets national building material quality standards. The method of the present invention is environmentally friendly and safe, improves the comprehensive utilization value of manganese slag, and achieves sustainable development.

Description

Technical Field

[0001] The present invention relates to the technical field of manganese slag waste treatment, in particular to a method and equipment for resource utilization and harmless treatment of manganese slag. Background Art

[0002] Electrolytic manganese slag is an industrial waste residue produced by filtration during the electrolytic production of metallic manganese. In the past, most companies discharged manganese slag in the form of open-air storage. However, during the stacking process, after long-term erosion and weathering, the heavy metal elements contained in the manganese slag will continuously enter the surrounding surface water, groundwater, soil and other ecological environments, causing serious impacts on the ecological environment of the mining area. According to the latest policy requirements, the manganese slag produced by the electrolytic manganese industry can only be treated harmlessly and long-term stacking is not allowed.

[0003] The harmless treatment of electrolytic manganese slag aims to reduce or remove Mn in manganese slag. 2+ and NH4 + Under such circumstances, metallic manganese and other metal substances are then recovered to achieve resource recycling and reuse. At present, the manganese slag produced by most domestic manganese industries is generally treated using methods such as high-temperature roasting and dry ammonium removal. Lime powder is used to alkalize the ammonium sulfate and manganese sulfate in the manganese slag, volatilizing a large amount of ammonia and forming manganese hydroxide, allowing the free ammonium sulfate and manganese sulfate to solidify and be used to make cement bricks or as cement admixtures. However, the costs incurred in this process are expensive and the cost consumption is high, and the maximum reasonable resource utilization is not achieved. Therefore, how to achieve the harmless treatment of electrolytic manganese slag and its resource utilization has become an imminent problem for the electrolytic manganese industry.

[0004] The following literature was retrieved on resource utilization and harmless treatment of manganese slag:

[0005] 1. Chinese Patent: "A Method for Treating Electrolytic Manganese Slag to Make it Harmless", Application No.: 201710916632.6; Abstract: The present invention discloses a method for treating electrolytic slag to make it harmless, the method comprising the following steps: (1) treating the manganese slag at a temperature of 450-900°C and an oxygen partial pressure of 10 -2 Pa~10 4 Pa for 0.5 to 4 hours; (2) using an aqueous solution containing a chelating agent or using dilute sulfuric acid to impregnate the manganese slag obtained in step (1) for 0.5 to 2 hours; (3) filtering the product obtained in step (2) and drying the filter cake to obtain harmless manganese slag. This method can make the color of the harmless treated manganese slag the same as that of local clay, and the concentration of harmful substances including heavy metals reaches the national agricultural soil standard. The harmless manganese slag can be used as soil for improving cultivated land, and can also be used for recultivating local desertified land.

[0006] 2. Chinese Patent: "A technology for pre-treating electrolytic manganese slag and preparing composite admixtures for concrete and resource utilization"; Application No.: 201811354272.6; Abstract: The present invention belongs to the field of industrial waste management technology and provides a technology for pre-treating electrolytic manganese slag and preparing composite admixtures for concrete, which is combined with harmless treatment and resource utilization. The technology includes: (1) pre-treatment; (2) preparing composite admixtures for concrete. The technology can solve the pollution problem of the existing technology that cannot remove ammonia nitrogen and soluble heavy metal manganese Mn in electrolytic manganese slag, and can also carry out more thorough harmless treatment and resource comprehensive utilization of electrolytic manganese slag; the technology is not only applicable to the harmless treatment and resource comprehensive utilization of large amounts of electrolytic manganese slag produced by large-scale electrolytic manganese enterprises, but also solves the industry problems in concentrated areas of electrolytic manganese industrialization, such as the small scale of individual electrolytic manganese enterprises and the difficulty in achieving economic disposal scale, by combining decentralized harmless pre-treatment with centralized preparation of composite admixtures for concrete.

[0007] 3. Chinese Patent: "Method for harmless treatment of electrolytic manganese slag"; Application No.: 201810589477.6; Abstract: The present invention discloses a method for harmless treatment of electrolytic manganese slag, comprising the following steps: (1) drying and crushing the electrolytic manganese slag, and then calcining it at low temperature to obtain a calcined material, and generating flue gas containing NH3 and SO2; (2) soaking the obtained calcined material in water, and then performing solid-liquid separation to obtain a filter residue and a manganese-containing filtrate; (3) drying the separated filter residue to obtain harmless manganese slag, adding a precipitant to the manganese-containing filtrate to precipitate manganese, and performing solid-liquid separation after the precipitation of manganese to obtain a manganese precipitate liquid and a manganese-containing product. The method of the present invention is not only simple in process, mild in process conditions, short in process time, and low in cost, but also can effectively achieve harmless resource treatment of electrolytic manganese slag, is green and environmentally friendly, and reduces the environmental pressure and production costs of related enterprises.

[0008] 4. Chinese Patent: "A harmless and resource-based disposal system for electrolytic manganese slag"; Application Number: 201910934265.1; Abstract: The present invention discloses a harmless and resource-based disposal system for electrolytic manganese slag, which relates to the field of solid waste management technology, including a hopper, a conveyor belt, a crusher, a pulping tank, a thickener, a stirring and leaching tank, a filter press, a clean water tank and a dosing barrel. There are n thickeners, and n ≥ 3. A stirring and leaching tank is provided between every two adjacent thickeners; the bottom discharge port of the nth thickener is connected to the filter press through a sludge pump; the water outlet of the clean water tank is connected to the feed port of the n-1th stirring and leaching tank through a centrifugal pump, and the top overflow outlets of the 3rd to nth thickeners are respectively connected to the feed ports of the 1st to n-2th stirring and leaching tanks through centrifugal pumps, and the top overflow outlet of the second thickener is connected to the pulping tank through a centrifugal pump. The present invention has reasonable structure, simple operation, excellent effect and effectively reduces the investment cost of enterprises.

[0009] 5. Chinese Patent: "A Method for Harmless Treatment and Resource Utilization of Electrolytic Manganese Slag"; Application Number: 201811241670.7; Abstract: The present invention discloses a method for harmless treatment and resource utilization of electrolytic manganese slag. The method comprises the following steps: first, calcium oxide and calcium carbonate are added to the leachate to effectively remove impurities such as iron, magnesium, and calcium; second, the pH of the leachate is adjusted with sodium hydroxide, and sodium carbonate is added to react to produce manganese carbonate; finally, calcium oxide is added and air stripping is performed to remove high concentrations of ammonia and nitrogen in the filtrate. The escaping gas is absorbed by clean water, and the filtrate is reused. The method effectively reduces the heavy metal and ammonia nitrogen content in the electrolytic manganese slag, shortens the leaching time of manganese and ammonia nitrogen, and improves the leaching rate of manganese and ammonia nitrogen from the electrolytic manganese slag. The manganese in the leachate is mainly recovered as manganese carbonate, which can be directly used as a raw material for electrolytic manganese metal. Furthermore, the leachate after the stripping reaction can be recycled.

[0010] The above-mentioned documents 1-3 all adopt the roasting method. The high temperature conditions will cause technical problems such as high energy consumption and high cost. If the gas generated after high temperature in documents 1-2 is directly discharged through desorption treatment, it will cause secondary pollution. In document 3, concentrated sulfuric acid is added for leaching. Sulfuric acid will react with the waste residue to produce harmful gases such as sulfur dioxide and hydrogen sulfide, thereby causing environmental pollution; the equipment involved in document 4 is numerous and complex, resulting in expensive equipment costs and thus increased production costs; in document 5, the harmless treatment of manganese slag requires multiple adjustments to the pH, resulting in cumbersome and complicated process steps. Summary of the Invention

[0011] In order to address the deficiencies of the prior art, the present invention aims to provide a method and process for resource utilization and harmless treatment of manganese slag. The method of the present invention can effectively recover soluble manganese and ammonium sulfate in the manganese slag, with a recovery rate of more than 80%. The waste slag obtained by filtration can be used to produce environmentally friendly bricks or used as fine sand for concrete mixing after harmless treatment. This method not only has low production costs, safety and environmental protection, but also can solve the current situation of long-term storage of electrolytic manganese slag, turning waste into treasure and achieving rational utilization of resources.

[0012] To achieve the above object, the present invention adopts the following technical methods;

[0013] (1) Put the manganese slag into a crusher and grind it through a 60-mesh sieve;

[0014] (2) Add clean water or slag washing water to the crushed manganese slag, heat it to 40-60℃, and stir it to form a slurry. The stirring time is 2 hours. The heating method can be to pass hot air into the manganese slag or to heat it in other ways.

[0015] (3) After stirring completely, filter press the mixture to obtain filter residue and filtrate, then add clean water to the filter residue or wash the residue and filter press the mixture multiple times to obtain a clean filter residue that does not contain manganese, and combine the multiple filtrates to obtain filtrate 1;

[0016] (4) Sulfidation treatment of filtrate 1: add 0.1 g / L sodium thiamethoxam to filtrate 1 to remove nickel. After the reaction is complete, add 0.2 ml / L impurity remover to remove calcium, magnesium and other complex salts. Press filter to obtain filtrate 2.

[0017] (5) Add 0.15 ml / L of hydrogen peroxide to filtrate 2 to remove iron. After the reaction is complete, filter press to obtain filtrate 3;

[0018] (6) 1.2 ml / L of a purification agent was added to the filtrate 3 for purification, the mixture was allowed to stand, and filter-pressed to obtain a filtrate 4; wherein the filtrate 4 contained 70-80 g / L of ammonium sulfate and 30-40 g / L of manganese sulfate;

[0019] (7) Selenium dioxide is added to the filtrate 4, and the filtrate is fed into an electrolytic cell for electrolysis for 24 hours, followed by removal from the cell, passivation, desulfurization, drying, and stripping to obtain an electrolytic manganese product; during the electrolysis, ammonium sulfate is added to the continuously consumed solution to ensure that the solution contains 80-100 g / L of ammonium sulfate;

[0020] (8) The filter residue in the above step (3) is subjected to a mass analysis to obtain the contents of soluble manganese, ammonium sulfate, pH, total iron, calcium, silicon, etc.; calcium oxide powder and a free ion curing agent are added according to the analysis results of the soluble manganese, and the mixture is evenly mixed, and the filter residue is crushed again to obtain a powder;

[0021] (9) The crushed filter residue is transported to the fermentation recovery tank, and composite bacteria are added to ferment for 12-24 hours. During this period, a large amount of ammonia generated is sent to the ammonia collector to produce ammonia water;

[0022] (10) After the fermentation time is reached, the material is discharged and sampled for analysis. Based on the analysis results, the filter residue that meets or is close to meeting the standards can be directly used to produce environmentally friendly bricks or used as fine sand for concrete mixing. The filter residue that does not meet the standards can be heated to 300°C in a dryer and baked for 2 hours until the filter residue quality meets the standards, and can be used as cement mixture.

[0023] The slag washing water described in step (2) is the water after the first or nth filter press; the slag washing water obtained after the previous one or several filter presses can be used to wash the continuously added manganese slag; generally, the manganese slag is washed with clean water when the machine is just started, and the manganese slag can be washed with a more diluted slag washing water for gradient washing to ensure the concentration of filtrate 1.

[0024] The impurity remover in step (4) is a mixture of ammonium bicarbonate, potassium permanganate, and acetic acid in a ratio of 0.5 to 1:2:0.1; the purpose of adding the impurity remover is to precipitate calcium and magnesium and remove other complex salts.

[0025] The purification agent described in step (6) is a mixture of polyferric chloride, polyacrylamide, and high-purity ammonium sulfate in a ratio of 5:0.1:1.

[0026] The amount of selenium dioxide added in step (7) is 10 mg / l.

[0027] The composite bacteria in step (9) are yeast, Bacillus and EM bacteria mixed in a ratio of 1-3:1:1, and the added amount is 0.5-1% of the mass of the filter residue; the purpose of fermentation is to remove organic matter in the manganese residue.

[0028] The equipment used includes a wet crusher, a mixing barrel, a vulcanizing mixing barrel, a Roots blower, a filter press, an electrolytic cell, a fermentation tank, an ammonia collector, and their supporting parts; the mixing barrel is equipped with a stirring motor, a Roots blower and a temperature sensor.

[0029] The fermentation tank is topped with a pulse dust collecting device and an air extraction port, the tank body is airtight, and the gas outlet pipe on the top is connected to an ammonia collector to recover the generated ammonia.

[0030] The slag washing water obtained after several filter presses contains manganese sulfate and 3-5 g / L of ammonium sulfate. It is necessary to add an appropriate amount of ammonium sulfate to reach an ammonium sulfate content of 80-100 g / L so that electrolysis can proceed. The electrolyte after electrolysis can be returned to the slag washing water.

[0031] In the electrolytic cell, the lead plate is used as the anode and the stainless steel is used as the cathode. The cell voltage is 4.2~4.5V and the current is 180~200A / m 2 , the effective area of the small electrolytic manganese plate is 0.036m 2 The electrolytic manganese output in 24 hours is more than 200g, which means that the output of a single cathode plate of the production line can reach more than 3.3kg; the current is the average current flowing through each square meter of the effective cathode area.

[0032] The equipment of the present invention includes: filter press, stirring barrel, electrolytic cell, fermentation tank, ammonia water collector, the functions and working principles of which are respectively described as follows:

[0033] 1. A stirring barrel, comprising a stirring barrel for early stage waste slag washing and a stirring barrel for later stage vulcanization; the stirring barrel for early stage waste slag washing is mainly a device for reacting manganese slag with slag washing water, the roots blower is turned on, and the temperature of the stirring barrel is controlled at 40-60°C with hot air, the crushed manganese slag reacts with the slag washing water, and stirring makes the reaction occur faster, and the reaction obtains dissolved metal sulfates, including manganese sulfate, ammonium sulfate and other metal salts, and after the reaction is complete, filter pressing is performed, and the obtained waste slag is added to the filter press for washing with slag washing water, and the mass ratio of waste slag to slag washing water is 0.3:1, and the washing is repeated for multiple (n) times, and then filter pressing is performed to separate the washed waste slag and a metal sulfate solution containing manganese sulfate and other metal sulfates, and the waste slag can be further harmlessly treated; a sulfiding agent and a decontaminating agent are added to the vulcanization stirring barrel to preliminarily purify the manganese sulfate, remove the insoluble metal salts generated by the reaction, and remove most impurities.

[0034] 2. Filter press. The present invention uses filter press multiple times, mainly to separate the precipitate after complete reaction from the solution. The filter press is started and squeezed until no water drips, separating waste residue and sulfate metal salts such as manganese sulfate. Then, the precipitate after complete reaction is separated from the solution to obtain a purified manganese sulfate solution.

[0035] 3. Electrolytic cell, the electrolytic cell electrolyzes manganese in manganese sulfate to obtain electrolytic manganese. After adding selenium dioxide to manganese sulfate, a lead plate is used as an anode and a stainless steel is used as a cathode. A specific current and voltage are applied (the electrolytic cell voltage is 4.2~4.5V and the current is 180~200A / m 2 ), electrolysis to obtain electrolytic manganese crude product, and then passivation, desulfurization, drying, stripping, to obtain high-purity electrolytic manganese product.

[0036] 4. Fermentation tank. The fermentation tank is a sealed tank body with air permeability inside the barrel. It is topped with a pulse dust collection device and an air extraction port. The tank body is airtight. The waste residue obtained by washing is added with calcium oxide and a free ion curing agent and transported to the fermentation tank for fermentation. During the fermentation process, the temperature continues to rise and the moisture decreases. The fermentation product gradually tends to be stable during the fermentation process. During this period, the ammonium salt decomposes to produce ammonia, which is recovered into the ammonia collector through the air extraction port. After the fermentation is completed, the fermentation product is sent for inspection. The waste residue that meets the standard or is close to meeting the standard can be directly used to produce environmentally friendly bricks or used as fine sand for concrete mixing; the waste residue that does not meet the standard can be heated to 300°C in a dryer and baked for 2 hours until the filter residue quality meets the standard, and can be used as cement mixture.

[0037] 5. Ammonia collector. The ammonia collector is connected to the top of the fermentation tank. After the fermentation tank produces ammonia, it is sucked into the ammonia collector from the exhaust port on the top of the fermentation tank. Clean water is injected into the ammonia collector in advance. Ammonia is passed into the clean water and dissolved to form ammonia water. The ammonia collector is also provided with an exhaust port to facilitate the discharge of air.

[0038] The beneficial effects of the present invention are:

[0039] 1. Normally, discarded manganese slag contains 1-2% soluble manganese and 3-5% ammonium sulfate, which exist in the form of free ions. Using water washing can not only wash out manganese and ammonium, but also some impurities. If it is directly fed into the production line circulating solution without a reasonable treatment method, it will cause abnormal production at the least and contaminate the production line at the worst, directly leading to production paralysis. The method of the present invention uses a small amount of harmless treatment agent to recover free manganese, ammonium sulfate and other substances, thereby reducing the free soluble manganese and ammonium sulfate in the manganese slag. After separating the waste slag from soluble sulfate metal salts such as manganese sulfate and ammonium sulfate, the filtrate is subjected to multiple impurity removal and filter pressing, and a sulfiding agent, impurity remover, oxidant and purifying agent are added to purify the filtrate, removing heavy metals such as nickel and calcium. The recovery rate of soluble manganese and ammonium sulfate can reach more than 80%. Manganese sulfate is electrolyzed to obtain a high-purity electrolytic manganese product, thereby achieving resource recycling and sustainable development.

[0040] 2. The present invention performs harmless treatment on the waste residue after washing and pressure filtration, and transports the waste residue to a fermentation tank for fermentation. The purpose of waste residue fermentation is to use calcium oxide and fermentation reagents to fully react with ammonium sulfate to form ammonia, reduce the ammonia nitrogen content in the waste residue, and achieve the waste residue meeting the building material quality standard. In addition, adding composite bacteria for auxiliary fermentation can remove the odor (organic matter) in the waste residue and accelerate the fermentation speed of the waste residue. The ammonia generated during the process can be transported to an ammonia collector for recovery to achieve rational utilization of resources. The waste residue after fermentation meets national standards and can be directly used to produce environmentally friendly bricks or used as fine sand for concrete mixing. The method of the present invention can turn waste residue into treasure and realize diversified resource utilization. The treatment process of the method of the present invention is safe and environmentally friendly, no harmful gas is generated, and the harm of manganese slag to my country's environment is reduced, thereby improving the problem of manganese slag stacking.

[0041] 3. The present invention electrolyzes the recovered manganese sulfate solution to produce electrolytic manganese. The electrolytic manganese product has high purity. After testing, the sulfur content in the product is ≤0.02%, and other impurities are all lower than the national standard. The manganese content in the product is ≥99.8%, reaching Class A products in the DJMn99.7% grade in the national standard. The heavy metal content is qualified and the product quality is good.

[0042] 4. In the method of the present invention, the waste residues that have been harmlessly treated are naturally air-dried and then subjected to quality analysis, and the pH value is ≤8, the manganese content is ≤1 mg / L, and the ammonia nitrogen content is ≤1.0 mg / L. The waste residues that have been fermented but not meeting the standards are heated and dried and then subjected to quality analysis, and the data obtained are: pH ≤9, manganese content ≤0.1 mg / L, and ammonia nitrogen content ≤0.7 mg / L, which are all less than the limit values of the national standard "Solid Waste Leaching Toxicity Leaching Method Horizontal Oscillation Method" (HJ557-2010). The obtained waste residues meet the national standards and can be used in the building materials industry, thereby improving the recovery rate of manganese residues.

[0043] 5. Compared with methods such as waste slag stacking and high-temperature roasting, the method of the present invention can process manganese slag at a lower production cost, turning waste into treasure, improving the profit and value of manganese slag. The cost is low, industrial production can be achieved, and the technical problem of high energy consumption and high cost caused by high temperature conditions is solved. Taking the production of 30,000 tons of electrolytic manganese products per year as an example, based on the manganese ore with a grade of 13%, the annual ore consumption can reach more than 300,000 tons, and the weight of the wet slag produced exceeds 400,000 tons. The stacking requires an initial investment in the design of a slag storage (calculated over ten years) and the subsequent annual maintenance costs. The average stacking cost per ton of slag is more than 230 yuan (the initial investment is calculated without interest). The method of the present invention can directly generate an economic benefit of more than 165 yuan per ton of slag (the production cost per ton of slag has been deducted). Compared with stacking waste slag, the difference can reach nearly 400 yuan. Compared with the stacking method, the annual 300,000 tons of manganese slag can generate an economic benefit of 120 million yuan, saving 60% of the investment and improving the economic benefit of manganese slag (the method of the present invention does not require investment in building a slag storage).

[0044] 6. The present invention can recycle low-grade manganese ore, and can also produce electrolytic manganese from high-sulfur and high-iron ores using the three-ore process; and can utilize waste gas recovery equipment to eliminate sulfuric acid mist, ammonia, hydrogen sulfide and dust pollution, and can achieve good wastewater treatment results. Some new processes have been tested in production, reducing pollutant emissions for many electrolytic manganese enterprises, contributing to the country's remediation of manganese slag environmental pollution, and having great significance for reducing the burden on manganese enterprises, benefiting the country and the people, while increasing economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 The present invention is a process flow chart of the method and equipment for resource utilization and harmless treatment of manganese slag. DETAILED DESCRIPTION

[0046] In order to introduce the present invention in more detail, the present invention will be further described below in conjunction with embodiments.

[0047] Example 1

[0048] A method and apparatus for resource utilization and harmless treatment of manganese slag, comprising the following steps:

[0049] (1) Put the manganese slag into a crusher and grind it through a 60-mesh sieve;

[0050] (2) Add clean water or slag washing water to the crushed manganese slag, introduce hot air to heat it to 40°C, and stir to form a slurry for 2 hours; the slag washing water is the water after the first or nth filter press;

[0051] (3) After stirring completely, filter press the mixture to obtain filter residue and filtrate, then add clean water to the filter residue or wash the residue and filter press the mixture multiple times to obtain a clean filter residue that does not contain manganese, and combine the multiple filtrates to obtain filtrate 1;

[0052] (4) Sulfidation treatment of filtrate 1: 0.1 g / L sodium thiamethoxam was added to filtrate 1 to remove nickel. After the reaction was complete, 0.2 ml / L of an impurity remover was added to remove calcium, magnesium and other complex salts. The mixture was filtered to obtain filtrate 2. The impurity remover was a mixture of ammonium bicarbonate, potassium permanganate and acetic acid in a ratio of 0.5:2:0.1.

[0053] (5) Add 0.15 ml / L of hydrogen peroxide to filtrate 2 to remove iron. After the reaction is complete, filter press to obtain filtrate 3;

[0054] (6) Add 1.2 ml / L of a purification agent to the filtrate 3 for purification, let it stand, and filter press to obtain a filtrate 4; the purification agent is a mixture of polyferric chloride, polyacrylamide, and high-purity ammonium sulfate in a ratio of 5:0.1:1;

[0055] (7) 10 mg / L of selenium dioxide is added to the filtrate 4, and the filtrate is put into an electrolytic cell for electrolysis for 24 hours, and then the filtrate is discharged, passivated, desulfurized, dried, and peeled to obtain an electrolytic manganese product; during the electrolysis, ammonium sulfate is added to the continuously consumed solution to ensure that the solution contains 80-100 g / L of ammonium sulfate; in the electrolytic cell, a lead plate is used as the anode and a stainless steel is used as the cathode. The cell voltage is 4.3 V and the current is 200 A / m 2 , the effective area of the small electrolytic manganese plate is 0.036m 2 The electrolytic manganese output in 24 hours is more than 200g, which means the cathode plate output of the production line can reach more than 3.3kg;

[0056] (8) The filter residue in the above step (3) is subjected to a mass analysis to obtain the contents of soluble manganese, ammonium sulfate, pH, total iron, calcium, silicon, etc.; calcium oxide powder and a free ion curing agent are added according to the analysis results of the soluble manganese, and the mixture is evenly mixed, and the filter residue is crushed again to obtain a powder;

[0057] (9) The crushed filter residue is transported to a fermentation recovery tank, and composite bacteria are added to ferment for 24 hours. During this period, a large amount of ammonia gas generated is sent to an ammonia gas collector to produce ammonia water; the composite bacteria are yeast, Bacillus and EM bacteria mixed in a ratio of 1:1:1, and the addition amount is 1% of the mass of the filter residue;

[0058] (10) After the fermentation time is reached, the material is discharged and sampled for analysis. Based on the analysis results, the filter residue that meets or is close to meeting the standards can be directly used to produce environmentally friendly bricks or used as fine sand for concrete mixing. The filter residue that does not meet the standards can be heated to 300°C in a dryer and baked for 2 hours until the filter residue quality meets the standards, and can be used as cement mixture.

[0059] Example 2

[0060] A method and apparatus for resource utilization and harmless treatment of manganese slag, comprising the following steps:

[0061] (1) Put the manganese slag into a crusher and grind it through a 60-mesh sieve;

[0062] (2) Add clean water or slag washing water to the crushed manganese slag, heat it to 60°C, and stir it to form a slurry. The stirring time is 2 hours. The slag washing water is the water after the first or nth filter press.

[0063] (3) After stirring completely, filter press the mixture to obtain filter residue and filtrate, then add clean water to the filter residue or wash the residue and filter press the mixture multiple times to obtain a clean filter residue that does not contain manganese, and combine the multiple filtrates to obtain filtrate 1;

[0064] (4) Sulfurization treatment of filtrate 1: 0.1 g / L sodium thiamethoxam was added to filtrate 1 to remove nickel. After the reaction was complete, 0.2 ml / L of an impurity remover was added to remove calcium, magnesium and other complex salts. The mixture was filtered to obtain filtrate 2. The impurity remover was a mixture of ammonium bicarbonate, potassium permanganate and acetic acid in a ratio of 1:2:0.1.

[0065] (5) Add 0.15 ml / L of hydrogen peroxide to filtrate 2 to remove iron. After the reaction is complete, filter press to obtain filtrate 3;

[0066] (6) Add 1.2 ml / L of a purification agent to the filtrate 3 for purification, let it stand, and filter press to obtain a filtrate 4; the purification agent is a mixture of polyferric chloride, polyacrylamide, and high-purity ammonium sulfate in a ratio of 5:0.1:1;

[0067] (7) Add 10 mg / L of selenium dioxide to the filtrate 4, send it into the electrolytic cell for electrolysis for 24 hours, remove it from the cell, passivate, desulfurize, dry it, and peel it to obtain an electrolytic manganese product; during the electrolysis, add ammonium sulfate to the continuously consumed solution to ensure that the solution contains 80-100 g / L of ammonium sulfate; in the electrolytic cell, a lead plate is used as the anode and a stainless steel is used as the cathode. The cell voltage is 4.3 V and the current is 200 A / m 2 , the effective area of the small electrolytic manganese plate is 0.036m 2 The electrolytic manganese output in 24 hours is more than 200g, which means the cathode plate output of the production line can reach more than 3.3kg;

[0068] (8) The filter residue in the above step (3) is subjected to a mass analysis to obtain the contents of soluble manganese, ammonium sulfate, pH, total iron, calcium, silicon, etc.; calcium oxide powder and a free ion curing agent are added according to the analysis results of the soluble manganese, and the mixture is evenly mixed, and the filter residue is crushed again to obtain a powder;

[0069] (9) The crushed filter residue is transported to a fermentation recovery tank, and composite bacteria are added to ferment for 18 hours. During this period, a large amount of ammonia gas generated is sent to an ammonia gas collector to produce ammonia water; the composite bacteria is a mixture of yeast, Bacillus and EM bacteria in a ratio of 3:1:1, and the addition amount is 0.5% of the mass of the filter residue;

[0070] (10) After the fermentation time is reached, the material is discharged and sampled for analysis. Based on the analysis results, the filter residue that meets or is close to meeting the standards can be directly used to produce environmentally friendly bricks or used as fine sand for concrete mixing. The filter residue that does not meet the standards can be heated to 300°C in a dryer and baked for 2 hours until the filter residue quality meets the standards, and can be used as cement mixture.

[0071] Example 3

[0072] A method and apparatus for resource utilization and harmless treatment of manganese slag, comprising the following steps:

[0073] (1) Put the manganese slag into a crusher and grind it through a 60-mesh sieve;

[0074] (2) Add clean water or slag washing water to the crushed manganese slag, introduce hot air to heat it to 50°C, and stir to form a slurry for 2 hours; the slag washing water is the water after the first or nth filter press;

[0075] (3) After stirring completely, filter press the mixture to obtain filter residue and filtrate, then add clean water to the filter residue or wash the residue and filter press the mixture multiple times to obtain a clean filter residue that does not contain manganese, and combine the multiple filtrates to obtain filtrate 1;

[0076] (4) Sulfurization treatment of filtrate 1: 0.1 g / L sodium thiamethoxam was added to filtrate 1 to remove nickel. After the reaction was complete, 0.2 ml / L of an impurity remover was added to remove calcium, magnesium and other complex salts. The mixture was filtered to obtain filtrate 2. The impurity remover was a mixture of ammonium bicarbonate, potassium permanganate and acetic acid in a ratio of 0.8:2:0.1.

[0077] (5) Add 0.15 ml / L of hydrogen peroxide to filtrate 2 to remove iron. After the reaction is complete, filter press to obtain filtrate 3;

[0078] (6) Add 1.2 ml / L of a purification agent to the filtrate 3 for purification, let it stand, and filter press to obtain a filtrate 4; the purification agent is a mixture of polyferric chloride, polyacrylamide, and high-purity ammonium sulfate in a ratio of 5:0.1:1;

[0079] (7) Add 10 mg / L of selenium dioxide to the filtrate 4, send it into the electrolytic cell for electrolysis for 24 hours, remove it from the cell, passivate, desulfurize, dry it, and peel it to obtain an electrolytic manganese product; during the electrolysis, add ammonium sulfate to the continuously consumed solution to ensure that the solution contains 80-100 g / L of ammonium sulfate; in the electrolytic cell, a lead plate is used as the anode and a stainless steel is used as the cathode. The cell voltage is 4.3 V and the current is 200 A / m 2 , the effective area of the small electrolytic manganese plate is 0.036m 2 The electrolytic manganese output in 24 hours is more than 200g, which means the cathode plate output of the production line can reach more than 3.3kg;

[0080] (8) The filter residue in the above step (3) is subjected to a mass analysis to obtain the contents of soluble manganese, ammonium sulfate, pH, total iron, calcium, silicon, etc.; calcium oxide powder and a free ion curing agent are added according to the analysis results of the soluble manganese, and the mixture is evenly mixed, and the filter residue is crushed again to obtain a powder;

[0081] (9) The crushed filter residue is transported to a fermentation recovery tank, and composite bacteria are added to ferment for 12 hours. During this period, a large amount of ammonia gas generated is sent to an ammonia gas collector to produce ammonia water; the composite bacteria is a mixture of yeast, Bacillus and EM bacteria in a ratio of 2:1:1, and the addition amount is 1% of the mass of the filter residue;

[0082] (10) After the fermentation time is reached, the material is discharged and sampled for analysis. Based on the analysis results, the filter residue that meets or is close to meeting the standards can be directly used to produce environmentally friendly bricks or used as fine sand for concrete mixing. The filter residue that does not meet the standards can be heated to 300°C in a dryer and baked for 2 hours until the filter residue quality meets the standards, and can be used as cement mixture.

[0083] Quality Analysis of Electrolytic Manganese Products

[0084] The electrolytic manganese products obtained by electrolysis of manganese sulfate solution in Examples 1-3 of the present invention were subjected to quality inspection according to the national standard "YB / T051-2015 Electrolytic Manganese Industry Standard". The inspection results are shown in Table 1.

[0085]

[0086] As can be seen from the product quality data in Table 1, the electrolytic manganese products produced by the method of the present invention have impurity data that are lower than the corresponding impurity indicators in the national standards, reaching the A-level product in the DJMn99.7% grade in the standard. It can be seen that the electrolytic manganese products produced by the method of the present invention are of good quality and high quality.

[0087] Manganese slag (harmless) quality analysis:

[0088] The fermented waste residue in Example 1 of the present invention was subjected to quality analysis. The quality analysis results are shown in Table 2:

[0089]

[0090] As can be seen from the above table, after heating and drying the waste residue that does not meet the standards in the fermentation tank, its pH value, manganese content and ammonia nitrogen content are all within the limit range of the national standard, and can be used for cement mixture; and after analysis of the waste residue that meets the standards after fermentation and is naturally air-dried, its indicators are also within the limit range of the national standard, and can be used to produce environmentally friendly bricks, which have good overall quality.

Claims

1. A method for resource utilization and harmless treatment of manganese slag, characterized in that: The following steps are involved: (1) Put the manganese slag into a crusher and grind it through a 60-mesh sieve; (2) Add clean water or slag washing water to the crushed manganese slag, heat it to 40-60℃, and stir it to form a slurry. The stirring time is 2h; (3) After stirring completely, filter press the mixture to obtain filter residue and filtrate, then add clean water to the filter residue or wash the residue and filter press the mixture multiple times to obtain a clean filter residue that does not contain manganese, and combine the multiple filtrates to obtain filtrate 1; (4) Sulfidation treatment of filtrate 1: 0.1 g / L sodium thiamethoxam was added to filtrate 1 to remove nickel. After the reaction was complete, 0.2 ml / L of an impurity remover was added to remove calcium, magnesium and other complex salts. The mixture was filtered to obtain filtrate 2. The impurity remover was a mixture of ammonium bicarbonate, potassium permanganate and acetic acid. (5) Add 0.15 ml / L of hydrogen peroxide to filtrate 2 to remove iron. After the reaction is complete, filter press to obtain filtrate 3; (6) Add 1.2 ml / L of a purification agent to the filtrate 3 for purification, let it stand, and filter press to obtain a filtrate 4; the purification agent is a mixture of polyferric chloride, polyacrylamide, and high-purity ammonium sulfate in a ratio of 5:0.1:1; (7) Adding electrolytic additive selenium dioxide to the filtrate 4, feeding it into the electrolytic cell for electrolysis for 24 hours, removing it from the cell, passivating, desulfurizing, drying, and peeling to obtain an electrolytic manganese product; (8) The filter residue in step (3) is subjected to a mass analysis to determine the content of soluble manganese, ammonium sulfate, pH, total iron, calcium, and silicon; calcium oxide powder and a free ion curing agent are added according to the analysis results of the soluble manganese, and the mixture is evenly mixed, and the filter residue is crushed again to obtain a powder; (9) The crushed filter residue is transported to a fermentation recovery tank, and composite bacteria are added to ferment for 12-24 hours. During this period, a large amount of ammonia gas generated is sent to an ammonia gas collector to produce ammonia water; the composite bacteria are yeast, Bacillus and EM bacteria mixed in a ratio of 1-3:1:1, and the addition amount is 0.5-1% of the mass of the filter residue; (10) After the fermentation time is reached, the material is discharged and sampled for analysis. Based on the analysis results, the filter residue that meets or is close to meeting the standards can be directly used to produce environmentally friendly bricks or used as fine sand for concrete mixing. The filter residue that does not meet the standards can be heated to 300°C in a dryer and baked for 2 hours until the filter residue quality meets the standards, and can be used as cement mixture.

2. The method for resource utilization and harmless treatment of manganese slag according to claim 1, characterized in that: The slag washing water in step (2) is the water after the first or nth filter press.

3. The method for resource utilization and harmless treatment of manganese slag according to claim 1, characterized in that: The amount of selenium dioxide added in step (7) is 10 mg / l.

4. The method for resource utilization and harmless treatment of manganese slag according to claim 1, characterized in that: The equipment used includes a wet crusher, a mixing barrel, a vulcanizing mixing barrel, a Roots blower, a filter press, an electrolytic cell, a fermentation tank, an ammonia collector, and their supporting parts; the mixing barrel is equipped with a stirring motor, a Roots blower and a temperature sensor.

5. The method for resource utilization and harmless treatment of manganese slag according to claim 4, characterized in that: The fermentation tank is topped with a pulse dust collecting device and an air extraction port, the tank body is airtight, and the gas outlet pipe on the top is connected to an ammonia collector to recover the generated ammonia.

6. The method for resource utilization and harmless treatment of manganese slag according to claim 1, characterized in that In the electrolytic cell, the lead plate is used as the anode and the stainless steel is used as the cathode. The cell voltage is 4.2~4.5V and the current is 180~200A / m 2 , the effective area of the small electrolytic manganese plate is 0.036m 2 The output of electrolytic manganese in 24 hours is more than 200g, which means the output of cathode plates per production line can reach more than 3.3kg.

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