A method for resource utilization of ammonia-containing waste generated during beryllium smelting.
By mixing, dealuminizing, regulating, and stripping the aluminum ammonium vanadium slag and beryllium washing wastewater generated during beryllium smelting, efficient recovery and resource utilization of ammonia nitrogen are achieved, solving the problem of incomplete ammonia nitrogen recovery in traditional treatment methods and providing a resource recycling path for clean production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HUNAN ZHONGJIN LINGNAN KANGMENG ENVIRONMENTAL PROTECTION TECH
- Filing Date
- 2026-01-23
- Publication Date
- 2026-05-26
AI Technical Summary
Incomplete recovery of ammonia nitrogen from ammonia-containing waste generated during beryllium smelting leads to serious resource waste. Traditional treatment methods are insufficient for efficient recovery and resource utilization of ammonia nitrogen, resulting in high production costs and increased environmental risks.
By mixing aluminum ammonium vanadium slag with beryllium washing wastewater, adding a calcium-containing conversion agent for dealuminization, and then reacting it with an acid or alkali regulator to generate ammonium salt or ammonia water, combined with stripping and precipitation decalcification steps, the full resource recovery of ammonia nitrogen is achieved.
The comprehensive recovery rate of ammonia nitrogen was achieved at no less than 94%, and the prepared ammonia water and ammonium salt products met national quality standards, solving the problems of resource waste and environmental pollution, and providing a clean production path for beryllium smelting.
Smart Images
Figure CN121553960B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a method for the resource utilization of ammonia-containing waste generated during beryllium smelting, belonging to the technical field of wastewater and waste residue treatment and resource utilization. Background Technology
[0002] The beryllium smelting process generates a large amount of ammonia-containing waste, mainly including aluminum ammonium vanadium slag, beryllium washing wastewater, and beryllium precipitation wastewater. These wastes not only contain high concentrations of ammonia nitrogen, but also contain valuable components such as beryllium, aluminum, and sulfur, as well as harmful substances. Traditional treatment methods suffer from problems such as incomplete ammonia recovery and serious resource waste.
[0003] The characteristics and composition of ammonia-containing waste from beryllium smelting are complex. Aluminum ammonium vanadium slag mainly contains aluminum, nitrogen, sulfur, and trace amounts of beryllium. Its ammonia nitrogen exists in the form of ammonium salts, making direct separation difficult. Beryllium washing wastewater mainly contains (NH4)2SO4, NaOH, and low concentrations of BeO; it is highly alkaline and exhibits large fluctuations in ammonia nitrogen concentration. Beryllium precipitation wastewater mainly contains high concentrations of (NH4)2SO4 and BeO.
[0004] Traditional ammonia recovery processes (such as stripping and precipitation) have significant limitations. For example, they are inefficient at removing bound ammonia from aluminum ammonium vanadium slag and low-concentration ammonia nitrogen from wastewater. Residual ammonia can easily cause secondary pollution, and the recovery is incomplete, failing to convert it into reusable raw materials. Especially in areas with ammonia shortages, purchasing ammonia significantly increases production costs.
[0005] Ammonia is a key raw material in beryllium smelting (for example, the beryllium precipitation process requires large amounts of ammonium salts). In resource-scarce regions, insufficient ammonia supply directly restricts capacity expansion. Existing technologies cannot efficiently and completely recover ammonia nitrogen from ammonia-containing waste, which exacerbates environmental risks and misses out on resource recovery value.
[0006] Therefore, there is an urgent need to develop a recycling method that can cover complex waste types and achieve full resource recovery of ammonia nitrogen. Summary of the Invention
[0007] To address the problems existing in the prior art, the present invention aims to provide a method for the resource utilization of ammonia-containing waste generated during beryllium smelting. This method fully utilizes the ammonia resources in aluminum ammonium vanadium slag, beryllium washing wastewater, and beryllium precipitation wastewater generated during beryllium smelting, and reuses them in the production process in the form of ammonium salts (ammonium sulfate or ammonium chloride) or ammonia water, thus realizing the full recycling of ammonia nitrogen in the production process.
[0008] To achieve the above objectives, a first aspect of the present invention provides a method for the resource utilization of ammonia-containing waste generated during beryllium smelting, the method comprising:
[0009] (1) Aluminum ammonium vanadium slag is mixed with beryllium washing wastewater to obtain an aluminum ammonium vanadium beryllium solution; the solid-liquid ratio of the aluminum ammonium vanadium slag to the beryllium washing wastewater is 3~6 m. 3 / t;
[0010] (2) The aluminum ammonium vanadium beryllium solution is mixed with a calcium-containing conversion agent to obtain aluminum-calcium slag and aluminum ammonium vanadium purified solution through conversion and dealuminization; the Ca in the calcium-containing conversion agent and the Al in the aluminum ammonium vanadium beryllium solution are mixed. 3+ The molar ratio is 1.5~2:1;
[0011] Acid adjustment: The aluminum ammonium vanadium purification solution is mixed with beryllium precipitation wastewater, and an acid regulator is added to the mixed solution. The acid regulator contains H... + The ammonium salt and evaporation condensate are obtained by evaporation crystallization with N in beryllium precipitation wastewater and aluminum ammonium vanadium purification solution at a molar ratio of 1.0 to 1.3.
[0012] Alternatively, alkali adjustment: Mix solution A with beryllium precipitation wastewater, add a calcium-containing alkaline substance to obtain an adjusted solution and gypsum residue; the OH- in the adjusted solution... - The molar ratio of N in solution A and the beryllium-precipitated wastewater is 1.1–1.4; a decalcifying agent is added to the adjusted liquid for precipitation and decalcification, yielding decalcified slag and decalcified liquid; steam is passed through the decalcified liquid for stripping ammonia, yielding ammonia water and ammonia stripping mother liquor; a beryllium precipitating agent is added to the ammonia stripping mother liquor for precipitation and decalcification, yielding beryllium slag and purified liquid, wherein the beryllium precipitating agent is a mixture of divalent and trivalent ferric salts;
[0013] Solution A is an aluminum ammonium vanadium beryllium solution and / or an aluminum ammonium vanadium purified solution.
[0014] This invention first involves mixing and dissolving aluminum ammonium vanadium slag with beryllium washing wastewater. This allows components from the aluminum ammonium vanadium slag to enter the aluminum ammonium vanadium beryllium solution. Then, a calcium-containing conversion agent is added. The Ca in the conversion agent reacts with Al in the aluminum ammonium vanadium beryllium solution to form calcium aluminate precipitate, thus separating Al and obtaining a purified aluminum ammonium vanadium solution. Removing Al allows for further purification of ammonium salts. If Al separation is not achieved during subsequent acid adjustment, Al will enter the ammonium salt product, affecting its purity.
[0015] Meanwhile, this invention can recover ammonia from aluminum ammonium vanadium beryllium solution, aluminum ammonium vanadium purification solution, and beryllium precipitation wastewater using various methods. Those skilled in the art can select the appropriate method based on the composition and properties of the ammonia-containing waste and the requirements for resource recovery products. The alkali adjustment method involves first adding a calcium-containing alkaline substance to the mixture of solution A (aluminum ammonium vanadium beryllium solution and / or aluminum ammonium vanadium purification solution) and beryllium precipitation wastewater to obtain an adjusted solution and gypsum slag. This step controls the ammonia nitrogen in the solution to the form of NH3·H2O and also removes sulfate ions from the solution. The purpose of removing sulfate ions is because a high sulfate concentration leads to excessively high salt content in the adjusted solution, increasing the risk of scaling in the stripping ammonia stripping system and increasing the solubility of the precipitate (beryllium slag) during beryllium removal, thus affecting the effectiveness of beryllium precipitation and removal. The conditioned liquid mainly contains Ca, N, and Be. A decalcifying agent is then added to precipitate and decalcify the conditioned liquid, removing calcium. Calcium removal prevents scaling in the ammonia stripping system, creating conditions for subsequent ammonia stripping. Finally, ferric salts (Fe3+ and Fe2+) are used to deeply remove beryllium from the mother liquor produced during the ammonia stripping process to meet emission standards. The use of ferric salts also facilitates the formation of ferrite precipitates, achieving efficient adsorption and co-precipitation of beryllium and ensuring that the beryllium concentration in the effluent meets the standards.
[0016] It should be noted that the transformation and dealuminization step can be carried out or not during alkali adjustment. That is, the aluminum ammonium vanadium beryllium solution obtained in step (1) can be used directly as one of the raw materials for alkali adjustment, the aluminum ammonium vanadium purified solution obtained in step (2) can be used as one of the raw materials for alkali adjustment, or a mixture of the aluminum ammonium vanadium beryllium solution obtained in step (1) and the aluminum ammonium vanadium purified solution obtained in step (2) can be used as one of the raw materials for alkali adjustment.
[0017] Acid conditioning mainly involves converting ammonia nitrogen in aluminum ammonium vanadium purification solution and beryllium precipitation wastewater into ammonium salts. Then, through evaporation and crystallization, the ammonium salts can be recovered in the form of crystalline salts, and the evaporation condensate can be reused in the beryllium smelting process.
[0018] This invention achieves efficient and coordinated treatment and disposal of ammonia-containing waste generated during beryllium smelting through the synergistic cooperation between various steps, with a comprehensive ammonia recovery rate of not less than 94%. Furthermore, the ammonia water prepared in this invention has a high concentration, and the ammonium salt obtained has a high purity (the quality of ammonium sulfate crystals meets the requirements of Type I ammonium sulfate in GB / T 535-2020). The alumina-calcium slag and gypsum slag are treated as general solid wastes, and the decalcified slag has a CaCO3 content of more than 95%, which can be reused as calcium-containing alkaline substances.
[0019] As a preferred embodiment, when using an alkaline adjustment method, the pH value of the adjusted solution is 10.5–12.0. Under these preferred conditions, the ammonia nitrogen in the solution can be controlled to the form of NH3·H2O.
[0020] As a preferred embodiment, the aluminum ammonium vanadium slag, on a dry basis, contains 5-7 wt% aluminum, 3-5 wt% nitrogen, 12-16 wt% sulfur, and 0.05-0.20 wt% beryllium.
[0021] The concentration of (NH4)2SO4 in the beryllium washing wastewater is 1~2 g / L, the concentration of NaOH is 5~15 g / L, and the concentration of BeO is 0.5~2 mg / L.
[0022] The concentration of (NH4)2SO4 in the beryllium precipitation wastewater is 100~150g / L, and the concentration of BeO is 3~100mg / L.
[0023] In this invention, aluminum ammonium vanadium slag refers to solid waste generated during the beryllium smelting process. Beryllium washing wastewater refers to wastewater generated during washing, dust removal, and other processes in the beryllium smelting process. Beryllium precipitation wastewater is wastewater generated during the beryllium smelting, leaching, and precipitation processes.
[0024] As a preferred embodiment, the calcium-containing transforming agent is selected from at least one of calcium oxide, calcium hydroxide, and calcium carbonate;
[0025] The calcium in the calcium-containing transforming agent and the Al in the aluminum ammonium vanadium beryllium solution 3+ The molar ratio is 1.5~1.8:1. Too little calcium will result in incomplete aluminum removal, while too much calcium will increase the dosage and cost of subsequent decalcification agents.
[0026] As a preferred embodiment, the calcium-containing alkaline substance is selected from at least one of calcium oxide, calcium hydroxide, and calcium carbonate;
[0027] The calcium-containing alkaline substance contains Ca, which reacts with solution A and the total SO4 in the beryllium-precipitated wastewater. 2- The molar ratio is 0.9~1.2:1.
[0028] As a preferred embodiment, in the acid conditioning step, the volume ratio of the aluminum ammonium vanadium purification solution to the beryllium precipitation wastewater is 1:0.4~0.6;
[0029] In the alkali adjustment step, the volume ratio of solution A to the beryllium precipitation wastewater is 1:0.4~0.6.
[0030] As a preferred embodiment, the decalcifying agent is selected from at least one of sodium carbonate, sodium bicarbonate, and carbon dioxide; the CO3 in the decalcifying agent... 2- HCO3 2- The sum of CO2 and Ca in the regulated liquid 2+ The molar ratio is 1.1~1.3:1;
[0031] During the precipitation and decalcification process, the pH of the adjusted solution is controlled to be between 10.5 and 12. The pH adjuster is sodium hydroxide solution and / or potassium hydroxide solution.
[0032] As a preferred embodiment, the steam temperature for the stripping of ammonia is 110~135℃;
[0033] The concentration of ammonia water is 18~25wt%.
[0034] As a preferred embodiment, in the beryllium precipitant, the divalent ferric salt is ferrous sulfate, and the trivalent ferric salt is polyferric sulfate and / or ferric chloride; and Fe 2+ with Fe 3+ The molar ratio is 1:3~10;
[0035] During the precipitation and deberyllium process, the pH value of the ammonia stripping mother liquor is controlled to be 8.5~9.5.
[0036] As a more preferred embodiment, the Fe in the beryllium precipitant 2+ and Fe 3+ The concentration of the sum in the ammonia stripping mother liquor is 20~60 g / m³. 3 .
[0037] As a preferred embodiment, the acid regulator is hydrochloric acid and / or sulfuric acid;
[0038] The conditions for the evaporation and crystallization include a temperature of 90~115℃.
[0039] As a preferred embodiment, when using an acid-adjusted method, the aluminum ammonium vanadium purification solution is mixed with beryllium precipitation wastewater, and an acidic adjuster is added to the mixed solution to adjust the pH value of the solution to ≤5. More preferably, the pH value is 2.5~4.5.
[0040] In this invention, the standard name of GB / T 535-2020 is "Fertilizer Grade Ammonium Sulfate", and the standard name of GB8978-1996 is "Integrated Wastewater Discharge Standard".
[0041] Compared with the prior art, the present invention has at least the following advantages:
[0042] This invention achieves the synergistic and efficient treatment and disposal of ammonia-containing wastes from beryllium smelting, such as aluminum ammonium vanadium slag, beryllium washing wastewater, and beryllium precipitation wastewater. It realizes the utilization of ammonia nitrogen resources in the beryllium smelting process, with a comprehensive ammonia recovery rate of no less than 94%. It solves the problem of difficult storage and reuse of acidic aluminum ammonium vanadium slag. The resource-based products such as ammonia water and ammonium salts (ammonium sulfate and / or ammonium chloride) meet the requirements of national quality standards and satisfy the needs of production reuse. The output of ammonia water and ammonium sulfate (ammonium chloride) can be flexibly adjusted according to production needs, providing a new resource recycling path for clean production and high-quality development in the beryllium smelting industry. Attached Figure Description
[0043] Figure 1 This is a process flow diagram of Embodiment 1 of the present invention. Detailed Implementation
[0044] The endpoints and any values of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of the various ranges, the endpoint values of the various ranges and individual point values, and individual point values can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.
[0045] The present invention will be further described below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments. Obviously, the embodiments described below are only a part of the embodiments, and all other embodiments obtained by those skilled in the art without creative effort are still within the scope of protection of the present invention.
[0046] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.
[0047] The aluminum ammonium vanadium slag contains Al: 5.96 wt%, N: 3.72 wt%, S: 14.01 wt%, and Be: 0.11 wt%.
[0048] The mass concentration of (NH4)2SO4 in the beryllium washing wastewater was 1.41 g / L, the mass concentration of NaOH was 10 g / L, and the mass concentration of BeO was 1 mg / L.
[0049] The mass concentration of (NH4)2SO4 in the beryllium precipitation wastewater was 135.38 g / L, and the mass concentration of BeO was 42 mg / L.
[0050] Example 1
[0051] (1) Mix 12t of aluminum ammonium vanadium slag with 50m 3 The beryllium washing wastewater was mixed and dissolved to obtain an aluminum ammonium vanadium beryllium solution.
[0052] (2) Add the transforming agent Ca(OH)2 to the aluminum ammonium vanadium beryllium solution, and control the molar ratio of Ca in the transforming agent to Al in the aluminum ammonium vanadium beryllium solution to be 1.5. Through transformation and dealuminization, 10.47t of aluminum-calcium slag with a moisture content of 15% and 48.4m of aluminum slag were obtained. 3 Aluminum ammonium vanadium purification solution.
[0053] (3) 48.4m 3 Aluminum ammonium vanadium purification solution and 25m 3The beryllium precipitation wastewater was mixed to obtain a liquid to be conditioned; this was done using a combination of partial alkaline and acidic conditioning.
[0054] For 25m 3 Acid adjustment of the solution to be adjusted: Add 25m 3 Add 0.54t of 98% H2SO4 (the acidic conditioner) to the solution to be conditioned. + The molar ratio of N in the beryllium precipitation wastewater and the aluminum ammonium vanadium purification solution was 1.0, the pH of the mixed solution was adjusted to 4.5, and the evaporation crystallization temperature was controlled at 95℃, yielding 1.89 t of ammonium sulfate crystals and 25.0 m... 3 Evaporation of condensate.
[0055] For 48.4m 3 Alkali adjustment of the solution to be adjusted: to 48.4m 3 Add Ca(OH)2 (calcium-containing alkaline substances) to the conditioning solution to react with the total SO4 in the aluminum ammonium vanadium purification solution and beryllium precipitation wastewater. 2- The molar ratio was 1.2:1, yielding 6.04 t of gypsum slag (calcium sulfate) with a moisture content of 25% and 46.62 m³ of... 3 Adjusted solution (OH in the adjusted solution) - The molar ratio of N in the aluminum ammonium vanadium purification solution and beryllium precipitation wastewater is 1.4:1.
[0056] (4) Add decalcifying agent Na2CO3 (CO3) to the adjusted solution. 2- With Ca in the adjusted solution 2+ The molar ratio was 1.1. Sodium hydroxide solution was used to adjust the pH value, and the pH of the solution after precipitation and decalcification was controlled to be 10.5. 46.56 mg / L was obtained through precipitation and decalcification. 3 Decalcified liquid and 0.22t of calcium carbonate slag with a moisture content of 20%;
[0057] (5) Steam was introduced into the decalcified liquid for stripping ammonia (steam temperature was 90℃) to obtain 10.17t of 18% ammonia water and ammonia stripping mother liquor;
[0058] (6) Add FeSO4 and polyferric sulfate and (Fe in the beryllium precipitant) to the mother liquor from ammonia stripping. 2+ and Fe 3+ The concentration of the sum in the ammonia stripping mother liquor is 20 g / m³. 3 Fe 2+ with Fe 3+ A 3.47 kg 30 wt% NaOH solution (molar ratio 1:3) was used, and the reaction pH was controlled at 8.5. After precipitation and de-beryllium removal, 1.44 kg of beryllium slag with a water content of 30% and 36.4 m³ of [unspecified substance] were obtained. 3 The purified liquid.
[0059] Calculations showed that the comprehensive recovery rate of ammonia nitrogen was 94%. Testing revealed that the ammonia concentration reached 18%, and the ammonium sulfate crystals met the requirements for Type I ammonium sulfate in GB / T 535-2020, with a nitrogen (N) mass fraction of 20.6% and a sulfur (S) mass fraction of 24.4%. The concentration of liquid beryllium after purification was below 5 μg / L. Alumina-calcium slag and gypsum slag (calcium sulfate) were disposed of as general solid waste, while calcium carbonate slag was reused as a calcium-containing alkaline substance.
[0060] Example 2
[0061] (1) Mix 12t of aluminum ammonium vanadium slag with 50m 3 The beryllium washing wastewater was mixed and dissolved to obtain an aluminum ammonium vanadium beryllium solution.
[0062] (2) Add the transforming agent Ca(OH)2 to the aluminum ammonium vanadium beryllium solution, and control the molar ratio of Ca in the transforming agent to Al in the aluminum ammonium vanadium beryllium solution to be 1.5. Through transformation and dealuminization, 10.47t of aluminum-calcium slag with a moisture content of 15% and 48.4m of aluminum slag were obtained. 3 Aluminum ammonium vanadium purification solution.
[0063] (3) 48.4m 3 Aluminum ammonium vanadium purification solution and 25m 3 The beryllium precipitation wastewater was mixed to obtain the conditioning solution; the conditioning was carried out using a fully acidic method.
[0064] Add 1.72t of 98% H2SO4 to the solution to be adjusted, so that the pH of the mixed solution is 2.5 (the acidity regulator contains H2SO4). + With the molar ratio of N in the beryllium precipitation wastewater and aluminum ammonium vanadium purification solution being 1.3, and the evaporation crystallization temperature controlled at 105℃, 5.56t of ammonium sulfate crystals and 73.7m were obtained. 3 Evaporation of condensate.
[0065] Calculations showed that the comprehensive recovery rate of ammonia nitrogen was 97.9%. Testing revealed that the quality of the ammonium sulfate crystals met the requirements for Type I ammonium sulfate in GB / T 535-2020, with a nitrogen (N) mass fraction of 20.7% and a sulfur (S) mass fraction of 24.4%. The alumina-calcium slag was disposed of as general solid waste.
[0066] Example 3
[0067] (1) Mix 12t of aluminum ammonium vanadium slag with 50m 3 The beryllium washing wastewater was mixed and dissolved to obtain an aluminum ammonium vanadium beryllium solution.
[0068] (2) Add the transforming agent Ca(OH)2 to the aluminum ammonium vanadium beryllium solution, and control the molar ratio of Ca in the transforming agent to Al in the aluminum ammonium vanadium beryllium solution to be 1.5. Through transformation and dealuminization, 10.47t of aluminum-calcium slag with a moisture content of 15% and 48.4m of aluminum slag were obtained. 3 Aluminum ammonium vanadium purification solution.
[0069] (3) 48.4m 3 Aluminum ammonium vanadium purification solution and 25m 3 The beryllium precipitation wastewater was mixed to obtain the liquid to be conditioned; the conditioning was carried out using a method of full alkali conditioning.
[0070] Add Ca(OH)2 (Ca from calcium-containing alkaline substances) to the solution to be adjusted, along with the total SO4 in the aluminum ammonium vanadium purification solution and beryllium precipitation wastewater. 2- The molar ratio was 0.9:1, yielding 7.6 t of gypsum slag with a moisture content of 25% and 71.1 m³ of... 3 Adjusted solution (OH in the adjusted solution) - The molar ratio of N in the aluminum ammonium vanadium purification solution and beryllium precipitation wastewater is 1.1.
[0071] (4) Add decalcifying agent Na2CO3 (CO3) to the adjusted solution. 2- With Ca in the adjusted solution 2+ The molar ratio was 1.3. Sodium hydroxide solution was used to adjust the pH, and the pH of the solution after precipitation and decalcification was controlled to be 12.0. 71.1 mg / L was obtained through precipitation and decalcification. 3 Decalcified liquid and 0.18t of calcium carbonate slag with a moisture content of 20%;
[0072] (5) Steam was introduced into the decalcified liquid for stripping ammonia (steam temperature was 115℃) to obtain 12.7t of ammonia water with a content of 22% and ammonia mother liquor;
[0073] (6) Add FeSO4 and FeCl3 (Fe from the beryllium precipitant) to the mother liquor of ammonia stripping. 2+ and Fe 3+ The concentration of the sum in the ammonia stripping mother liquor is 60 g / m³. 3 Fe 2+ with Fe 3+ The reaction mixture (molar ratio of 1:10) and 16.7 kg of 30% NaOH solution were used, with the pH controlled at 9.5. After precipitation and de-beryllium removal, 6.9 kg of beryllium slag with a water content of 30% and 58.4 m³ of [unspecified substance] were obtained. 3 The purified liquid.
[0074] Calculations showed that the comprehensive recovery rate of ammonia nitrogen was 94.8%. Testing revealed that the ammonia concentration in the water reached 22%, meeting reuse requirements, and the concentration of beryllium in the purified liquid was below 5 μg / L. Aluminum-calcium slag and gypsum slag (calcium sulfate) were disposed of as general solid waste, while calcium carbonate slag was reused as a calcium-containing alkaline substance.
[0075] Comparative Example 1
[0076] Steps (1) to (5) are the same as in Example 1;
[0077] Step (6): Add FeSO4 (Fe from the beryllium precipitant) to the ammonia stripping mother liquor. 2+The concentration in the ammonia stripping mother liquor was 20 g / m³. 3 3.49 kg of 30 wt% NaOH solution was used, and the reaction pH was controlled at 8.5. After precipitation and de-beryllium removal, 1.44 kg of beryllium slag with a water content of 30% and 36.6 m³ of [unspecified substance] were obtained. 3 The purified liquid.
[0078] Calculations showed that the comprehensive recovery rate of ammonia nitrogen was 95.9%. Testing revealed that the ammonia concentration reached 20%, and the ammonium sulfate crystals met the requirements for Type I ammonium sulfate in GB / T 535-2020, with an N mass fraction of 20.5% and a S mass fraction of 24.1%. The purified liquid beryllium concentration was 27 μg / L, which does not meet the emission standards (GB8978-1996). Alumina-calcium slag and gypsum slag (calcium sulfate) were disposed of as general solid waste, while calcium carbonate slag was reused as a calcium-containing alkaline substance.
[0079] Comparative Example 2
[0080] (1) Mix 12t of aluminum ammonium vanadium slag with 50m 3 The beryllium washing wastewater was mixed and dissolved to obtain an aluminum ammonium vanadium beryllium solution.
[0081] (2) Add the transforming agent Ca(OH)2 to the aluminum ammonium vanadium beryllium solution, and control the molar ratio of Ca in the transforming agent to Al in the aluminum ammonium vanadium beryllium solution to be 1.2. Through transformation and dealuminization, 8.86t of aluminum-calcium slag with a moisture content of 15% and 48.7m of aluminum slag were obtained. 3 Aluminum ammonium vanadium purification solution.
[0082] (3) 48.7m 3 Aluminum ammonium vanadium purification solution and 25m 3 The beryllium precipitation wastewater was mixed to obtain a liquid to be conditioned; this was done using a combination of partial alkaline and acidic conditioning.
[0083] For 25m 3 Acid adjustment of the solution to be adjusted: Add 25m 3 Add 0.54t of 98% H2SO4 (the acidic conditioner) to the solution to be conditioned. + The molar ratio of N in the beryllium precipitation wastewater and the aluminum ammonium vanadium purification solution was 1.0, the pH of the mixed solution was adjusted to 4.5, and the evaporation crystallization temperature was controlled at 95℃, yielding 1.85 t of ammonium sulfate crystals and 25.0 m... 3 Evaporation of condensate.
[0084] For 48.7m 3 Alkali adjustment of the solution to be adjusted: to 48.7m 3 Add Ca(OH)2 (calcium-containing alkaline substances) to the conditioning solution to react with the total SO4 in the aluminum ammonium vanadium purification solution and beryllium precipitation wastewater. 2-The molar ratio was 1:1, yielding 5.05 t of gypsum slag (calcium sulfate) with a moisture content of 25% and 47.2 m³ of... 3 Adjusted solution (OH in the adjusted solution) - The molar ratio of N in the aluminum ammonium vanadium purification solution and beryllium precipitation wastewater is 1.3:1.
[0085] (4) Add decalcifying agent Na2CO3 (CO3) to the adjusted solution. 2- With Ca in the adjusted solution 2+ The molar ratio was 1.1. Sodium hydroxide solution was used to adjust the pH, and the pH of the solution after precipitation and decalcification was controlled to be 10.5. 47.1 m³ was obtained through precipitation and decalcification. 3 Decalcified liquid and 0.12t of calcium carbonate slag with a moisture content of 20%;
[0086] (5) Steam was introduced into the decalcified liquid for stripping ammonia (steam temperature was 90℃) to obtain 10.3 t of ammonia water with 18% content and ammonia mother liquor;
[0087] (6) Add FeSO4 and polyferric sulfate and (Fe in the beryllium precipitant) to the mother liquor from ammonia stripping. 2+ and Fe 3+ The concentration of the sum in the ammonia stripping mother liquor is 20 g / m³. 3 Fe 2+ with Fe 3+ The molar ratio was 1:3), and 3.5 kg of 30 wt% NaOH solution was used. The reaction pH was controlled at 8.5. After precipitation and de-beryllium removal, 1.45 kg of beryllium slag with a water content of 30% and 36.8 m³ of [unclear - possibly a specific substance or product] were obtained. 3 The purified liquid.
[0088] Calculations showed that the comprehensive recovery rate of ammonia nitrogen was 96.2%. Testing revealed that the ammonia concentration in the water reached 18%, and the nitrogen content in the ammonium sulfate crystals was 16.6%, failing to meet the requirements for Type I and Type II ammonium sulfate in GB / T 535-2020. The beryllium concentration in the purified liquid was below 5 μg / L. Aluminum-calcium slag and gypsum slag (calcium sulfate) were disposed of as general solid waste, while calcium carbonate slag was reused as a calcium-containing alkaline substance.
[0089] Comparative Example 3
[0090] The difference from Example 2 is that the solid-liquid ratio of aluminum ammonium vanadium slag and beryllium washing wastewater is changed.
[0091] (1) Mix 12t of aluminum ammonium vanadium slag with 12m 3 The beryllium washing wastewater was mixed and dissolved to obtain an aluminum ammonium vanadium beryllium solution.
[0092] (2) Add the transforming agent Ca(OH)2 to the aluminum ammonium vanadium beryllium solution, and control the molar ratio of Ca in the transforming agent to Al in the aluminum ammonium vanadium beryllium solution to be 1.5. Through transformation and dealuminization, 10.47t of aluminum-calcium slag with a moisture content of 15% and 10.4m of aluminum calcium slag were obtained. 3 Aluminum ammonium vanadium purification solution.
[0093] (3) 10.4m 3 Aluminum ammonium vanadium purification solution and 25m 3 The beryllium precipitation wastewater was mixed to obtain the conditioning solution; the conditioning was carried out using a fully acidic method.
[0094] Towards 35.4m 3 Add 0.78t of 98% H2SO4 (the acidic conditioner) to the solution to be adjusted. + The molar ratio of N in the beryllium precipitation wastewater and the aluminum ammonium vanadium purification solution was 1.3, the pH of the mixed solution was adjusted to 2.5, and the evaporation crystallization temperature was controlled at 105℃, yielding 2.58 t of ammonium sulfate crystals and 35.4 m... 3 Evaporation of condensate.
[0095] Calculations showed that the comprehensive recovery rate of ammonia nitrogen was 46.9%. Testing revealed that the quality of the ammonium sulfate crystals met the requirements for Type I ammonium sulfate in GB / T 535-2020, with a nitrogen mass fraction of 20.5% and a sulfur mass fraction of 24.2%. The alumina-calcium slag was disposed of as general solid waste.
[0096] Comparative Example 4
[0097] (1) Mix 12t of aluminum ammonium vanadium slag with 50m 3 The beryllium washing wastewater was mixed and dissolved to obtain an aluminum ammonium vanadium beryllium solution.
[0098] (2) Mix aluminum ammonium vanadium beryllium solution with 25m 3 The beryllium precipitation wastewater was mixed to obtain a liquid to be conditioned; this was done using a combination of partial alkaline and acidic conditioning.
[0099] For 25m 3 Acid adjustment of the solution to be adjusted: Add 25m 3 Add 0.54t of 98% H2SO4 (the acidic conditioner) to the solution to be conditioned. + The molar ratio of N in the beryllium precipitation wastewater and the aluminum ammonium vanadium purification solution was 1.0, the pH of the mixed solution was adjusted to 2.3, and the evaporation crystallization temperature was controlled at 95℃, yielding 2.79t of ammonium sulfate crystals and 25.0m of [unclear - possibly a specific product or solution]. 3 Evaporation of condensate.
[0100] For 50.4m 3 Alkali adjustment of the solution to be adjusted: Add Ca(OH)2 (calcium-containing alkaline substances) to the solution to adjust the total SO4 in the aluminum ammonium vanadium purification solution and beryllium precipitation wastewater. 2-The molar ratio was 1:1, yielding 9.62 t of gypsum slag (mainly calcium sulfate) with a moisture content of 25% and 47.51 m³ of... 3 Adjusted solution (OH in the adjusted solution) - The molar ratio of N in the aluminum ammonium vanadium purification solution and beryllium precipitation wastewater is 1.05:1.
[0101] (3) Add 0.11t of decalcifying agent Na2CO3 (CO3) to the adjusted solution. 2- With Ca in the adjusted solution 2+ The molar ratio was 1.1. Sodium hydroxide solution was used to adjust the pH value, and the pH of the solution after precipitation and decalcification was controlled to be 10.5. 47.11 mg was obtained through precipitation and decalcification. 3 Decalcified liquid and 0.12t of calcium carbonate slag with a moisture content of 20%;
[0102] (4) Steam was introduced into the decalcified liquid for stripping ammonia (steam temperature was 90℃) to obtain 10.379t of ammonia water with a content of 18% and ammonia mother liquor;
[0103] (5) Add FeSO4 and polyferric sulfate and (Fe in the beryllium precipitant) to the mother liquor from ammonia stripping. 2+ and Fe 3+ The concentration of the sum in the ammonia stripping mother liquor is 20 g / m³. 3 Fe 2+ with Fe 3+ The molar ratio was 1:3), and 3.53 kg of 30wt% NaOH solution was used. The reaction pH was controlled at 8.5. After precipitation and de-beryllium removal, 1.46 kg of beryllium slag with a water content of 30% and 37.1 m³ of [unclear - possibly a specific substance or product] were obtained. 3 The purified liquid.
[0104] Calculations showed that the comprehensive recovery rate of ammonia nitrogen was 96.6%. Testing revealed that the ammonia concentration reached 18%, and the ammonium sulfate crystal quality did not meet the requirements for Type I and Type II ammonium sulfate in GB / T 535-2020. The nitrogen (N) mass fraction was 13.5%, the sulfur (S) mass fraction was 15.9%, and the beryllium concentration after purification was below 5 μg / L. Alumina-calcium slag and gypsum slag (calcium sulfate) were disposed of as general solid waste, while calcium carbonate slag was reused as a calcium-containing alkaline substance.
[0105] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.
Claims
1. A method for the resource utilization of ammonia-containing waste generated during beryllium smelting, characterized in that: The method includes: (1) aluminum ammonium vanadium slag is mixed with beryllium washing wastewater to obtain an aluminum ammonium vanadium beryllium dissolving solution; the solid-liquid ratio of the aluminum ammonium vanadium slag to the beryllium washing wastewater is 3-6 m 3 / t; (2) The aluminum ammonium vanadium beryllium solution is mixed with a calcium-containing conversion agent to obtain aluminum-calcium slag and aluminum ammonium vanadium purified solution through conversion and dealuminization; the Ca in the calcium-containing conversion agent and the Al in the aluminum ammonium vanadium beryllium solution are mixed. 3+ The molar ratio is 1.5~2:1; Acid adjustment: The aluminum ammonium vanadium purification solution is mixed with beryllium precipitation wastewater, and an acid regulator is added to the mixed solution. The acid regulator contains H... + The ammonium salt and evaporation condensate are obtained by evaporation crystallization with N in beryllium precipitation wastewater and aluminum ammonium vanadium purification solution at a molar ratio of 1.0 to 1.
3. Alternatively, alkali adjustment: Mix solution A with beryllium precipitation wastewater, add a calcium-containing alkaline substance to obtain an adjusted solution and gypsum residue; the OH- in the adjusted solution... - The molar ratio of N in solution A and the beryllium-precipitated wastewater is 1.1–1.
4. A decalcifying agent is added to the adjusted liquid to precipitate and decalcify, resulting in decalcified slag and decalcified liquid. Steam is passed through the decalcified liquid to strip ammonia, resulting in ammonia water and ammonia stripping mother liquor. A beryllium precipitating agent is added to the ammonia stripping mother liquor to precipitate and decalcify beryllium, resulting in beryllium slag and purified liquid. The beryllium precipitating agent is a mixture of ferrous and ferric salts. CO3 in the decalcifying agent 2- HCO3 2- The sum of CO2 and Ca in the regulated liquid 2+ The molar ratio is 1.1~1.3:1; during the precipitation and decalcification process, the pH value of the adjusted solution is controlled to be 10.5~12; In beryllium precipitants, the divalent ferric salt is ferrous sulfate, and the trivalent ferric salt is polyferric sulfate and / or ferric chloride; and Fe 2+ with Fe 3+ The molar ratio is 1:3~10; During the precipitation and deberyllium process, the pH value of the ammonia stripping mother liquor is controlled to be 8.5~9.5; Solution A is an aluminum ammonium vanadium beryllium solution and / or an aluminum ammonium vanadium purified solution.
2. The method for resource utilization of ammonia-containing waste generated during beryllium smelting according to claim 1, characterized in that: The aluminum ammonium vanadium slag, on a dry basis, contains 5-7 wt% aluminum, 3-5 wt% nitrogen, 12-16 wt% sulfur, and 0.05-0.20 wt% beryllium. The concentration of (NH4)2SO4 in the beryllium washing wastewater is 1~2 g / L, the concentration of NaOH is 5~15 g / L, and the concentration of BeO is 0.5~2 mg / L. The concentration of (NH4)2SO4 in the beryllium precipitation wastewater is 100~150g / L, and the concentration of BeO is 3~100mg / L.
3. A method for resource utilization of ammonia-containing waste generated during beryllium smelting according to claim 1 or 2, characterized in that: In the acid conditioning step, the volume ratio of the aluminum ammonium vanadium purification solution to the beryllium precipitation wastewater is 1:0.4~0.6; In the alkali adjustment step, the volume ratio of solution A to the beryllium precipitation wastewater is 1:0.4~0.
6.
4. A method for resource utilization of ammonia-containing waste generated during beryllium smelting according to claim 1 or 2, characterized in that: The calcium-containing transforming agent is selected from at least one of calcium oxide, calcium hydroxide, and calcium carbonate; The calcium in the calcium-containing transforming agent and the Al in the aluminum ammonium vanadium beryllium solution 3+ The molar ratio is 1.5~1.8:
1.
5. A method for resource utilization of ammonia-containing waste generated during beryllium smelting according to claim 1 or 2, characterized in that: The calcium-containing alkaline substance is selected from at least one of calcium oxide, calcium hydroxide, and calcium carbonate; The calcium-containing alkaline substance contains Ca, which reacts with solution A and the total SO4 in the beryllium-precipitated wastewater. 2- The molar ratio is 0.9~1.2:
1.
6. A method for resource utilization of ammonia-containing waste generated during beryllium smelting according to claim 1 or 2, characterized in that: The decalcifying agent is selected from at least one of sodium carbonate, sodium bicarbonate, and carbon dioxide.
7. A method for resource utilization of ammonia-containing waste generated during beryllium smelting according to claim 1 or 2, characterized in that: The steam temperature for stripping ammonia is 110~135℃; The concentration of ammonia water is 18~25wt%.
8. A method for resource utilization of ammonia-containing waste generated during beryllium smelting according to claim 1, characterized in that: Fe in the beryllium precipitant 2+ and Fe 3+ The concentration of the sum in the ammonia stripping mother liquor is 20~60 g / m³. 3 .
9. A method for resource utilization of ammonia-containing waste generated during beryllium smelting according to claim 1, characterized in that: The acid regulator is hydrochloric acid and / or sulfuric acid; The conditions for the evaporation and crystallization include a temperature of 90~115℃.