Process for the recovery of metallurgical dusts containing lead and alkali elements

Abstract

The present application belongs to the field of metal material processing, and particularly relates to a recovery method of metallurgical dust containing lead and alkali metal elements, which comprises the following steps: subjecting the metallurgical dust containing lead and alkali metal elements and a modifier to leaching treatment in water; dissolving the alkali metal elements in the metallurgical dust and converting the lead elements into hydrocerussite precipitates; then, subjecting the solid-liquid separation to obtain water leaching liquid rich in alkali metal and water leaching residue containing hydrocerussite; the modifier comprises alkaline earth metal-based material and / or alkali metal-based material, the alkaline earth metal-based material is at least one of oxides, hydroxides, chlorides and nitrates of alkaline earth metals, and the alkali metal-based material is at least one of carbonates, bicarbonates and carboxylates of alkali metals. The present application can selectively convert the lead in the metallurgical dust into hydrocerussite phase, reduce the accompanying precipitation of potassium, realize the deep extraction of alkali metal, and improve the recovery rate of alkali metal elements.

Description

Technical Field

[0001] This invention pertains to solid waste treatment methods, specifically relating to the recovery and treatment of metallurgical dust containing lead and alkali metal elements. Background Technology

[0002] With the development of the steel industry, smelting solid waste, represented by steel metallurgical dust, has put pressure on environmental protection. Taking sintering machine dust as an example, this type of dust is a micron-sized solid waste generated during the iron ore sintering process and collected by electrostatic precipitators, accounting for approximately 1.5% of crude steel production. This dust contains large amounts of iron, alkali metals (potassium, sodium), lead, and chloride. Currently, the most common method is to return the sintering machine dust to the sintering furnace to recover the iron. However, elements such as potassium, sodium, and lead in the dust will accumulate in large quantities during this process. During the iron ore sintering process, alkali metals in natural minerals undergo reduction, oxidation, and combination with silica, and then react with calcium chloride, ultimately existing in the steel metallurgical dust in the form of potassium chloride and sodium chloride. This portion of alkali metals has a significant chance of dissolving, and water leaching is expected to extract these alkali metal elements.

[0003] Existing technologies also report some water leaching extraction processes. For example, patent document CN107626711A discloses a method for the resource recovery of potassium-containing dust, specifically describing a scheme for leaching KCl from dried tailings ash mixed with water. Patent document CN119824231A discloses a process for recovering multiple valuable elements such as lead, zinc, silver, and potassium from steel plant flue dust, which also discloses a scheme for directly extracting alkali metals from steel plant flue dust using water leaching.

[0004] Although, theoretically, alkali metals in steelmaking dust have good water solubility and can be extracted through water leaching, relevant research results show that water leaching is difficult to achieve deep removal of potassium. For example, under conditions of 30 °C, 30 min, and a liquid-to-solid ratio of 7 mL / g, the leaching rate of potassium in steelmaking dust in aqueous solution can only reach 85.46%. In response to this situation, most steelmaking dust treatment companies generally adopt a two-step circulating water leaching process. While this method has a certain promoting effect on potassium removal, the residual alkali metal content in the treated water-leached slag is still as high as 5% or more. Furthermore, the overall process of this treatment is relatively long, which increases the processing cost. Moreover, current mainstream steelmaking dust recovery processes mainly focus on the separation and extraction of potassium, iron, and zinc resources, with little involvement in the co-recovery of lead. Summary of the Invention

[0005] In view of the existing problems that it is difficult to deeply extract alkali metals from metallurgical dust containing lead and alkali metals, and difficult to achieve secondary utilization of lead, the purpose of this invention is to provide a method for recycling metallurgical dust containing lead and alkali metals, which aims to deeply extract the alkali metals and achieve highly selective separation and secondary recycling of lead and alkali metals.

[0006] The main challenge in the high-value recovery of metallurgical dust containing lead and alkali metals stems from its unique physicochemical characteristics: its composition is complex and variable. Lead and alkali metals (potassium, sodium) often coexist closely in the form of chlorides and sulfates. These alkali metal salts are theoretically soluble in water, but the large amount of potassium (K) coexisting in aqueous solutions is a significant issue. + Na + Pb 2+ Furthermore, interactions between anions can generate complex substances (such as lead-potassium precipitates), which restricts the efficient and deep separation and recovery of target metal ions. To address this problem, this invention, after in-depth research, provides the following improvement:

[0007] A method for recovering metallurgical dust containing lead and alkali metal elements involves leaching the metallurgical dust and conditioning agent in water (also known as water leaching treatment); this process dissolves the alkali metal elements in the metallurgical dust and converts the lead elements into hydroxyl chloride precipitate; subsequently, solid-liquid separation is performed to obtain a water leaching solution enriched with alkali metals and a water leaching residue containing hydroxyl chloride precipitate.

[0008] The conditioning agent comprises alkaline earth metal-based materials and / or alkali metal-based materials, wherein the alkaline earth metal-based materials are at least one of the oxides, hydroxides, chlorides, and nitrates of alkaline earth metals; and the alkali metal-based materials are at least one of the carbonates, bicarbonates, and carboxylates of alkali metals.

[0009] Alkali metals include at least one element selected from sodium and / or potassium;

[0010] In the metallurgical dust containing lead and alkali metal elements, the lead-bearing phase includes PbCl2; the alkali metal-bearing phase includes at least one of alkali metal chloride and alkali metal sulfate; wherein the lead content is 2wt%~10wt%, the alkali metal content is 5wt%~40wt%, and the chlorine content is 10wt%~30wt%.

[0011] The amount of conditioning agent used is 0.2% to 10% of the weight of metallurgical dust.

[0012] This invention innovatively demonstrates that, under the aforementioned conditioning agent, the water leaching treatment can selectively convert lead into a lead hydroxychlorophosphate mineral phase, reducing the accompanying precipitation of potassium. This enables deep extraction of alkali metals and improves the recovery rate of alkali metal elements. Furthermore, unlike conventional water leaching processes that struggle to extract lead from the leaching residue a second time, this invention utilizes a simple extraction process to leach lead from the leaching residue, achieving efficient recovery of lead resources.

[0013] In this invention, the metallurgical dust containing lead and alkali metal elements contains the following components and contents: iron content of 20wt%~30wt%, potassium content of 15wt%~20wt%, sodium content of 1.0wt%~2wt%, lead content of 4wt%~6wt%, chlorine content of 20wt%~22wt%, and sulfur content of 1wt%~2wt%. The iron-bearing phases include Fe2O3 and Fe3O4, with Fe3O4 accounting for 50% to 60% of the Fe phase (total weight of Fe2O3 and Fe3O4); the potassium-bearing phases include KCl and K2SO4, with KCl accounting for 90 wt% to 95 wt% of the K phase (total weight of KCl and K2SO4); the sodium-bearing phases include NaCl and Na2SO4, with NaCl accounting for 80 wt% to 90 wt% of the Na phase (total weight of NaCl and Na2SO4); and the PbCl2 content is 75 wt% to 80 wt% of the total Pb phase.

[0014] In this invention, the alkaline earth metal in the alkaline earth metal-based material can be at least one of Ca, Mg, Ba, and Sr; more specifically, it can be Ca. Studies have shown that using a calcium-based conditioning agent can achieve better alkali metal water immersion results.

[0015] In this invention, the alkaline earth metal-based material in the conditioning agent can be at least one of calcium oxide and calcium hydroxide; further, it can include calcium oxide and calcium hydroxide in a weight ratio of 5 to 10:1. Studies have shown that preferred calcium-based materials, when used as conditioning agents, can achieve better alkali metal water immersion effects.

[0016] In summary, the alkali metal-based material mentioned in this invention can be at least one of potassium carbonate and sodium carbonate.

[0017] In this invention, the conditioning agent comprises alkaline earth metal-based materials and alkali metal-based materials. Preferably, the conditioning agent can further induce the selective synthesis of the hydroxyl chloride lead mineral phase, and based on this idea, improve the water leaching coupling effect of alkali metals.

[0018] In the conditioning agent, the weight ratio of alkaline earth metal-based material to alkali metal-based material is 5~10:1; it can be further 8~10:1.

[0019] In this invention, the conditioning agent is 0.3% to 5% of the weight of metallurgical dust containing lead and alkali metal elements. Considering cost, it can be further 0.5% to 3%, and even further 0.5% to 1%.

[0020] In this invention, the temperature and time of the leaching process can be adjusted reasonably as needed.

[0021] In this invention, the temperature of the leaching process is 0 ℃~60 ℃; further, it can be 10 ℃~40 ℃, and even further, it can be 20 ℃~30 ℃.

[0022] The leaching time is 1 min to 60 min; considering processing efficiency, it can be further reduced to 5 min to 15 min, and even further reduced to 8 min to 12 min. This invention is based on the coupling of hydroxyl chloride lead ore and alkali metal leaching, which can achieve efficient leaching in a relatively short time.

[0023] The liquid-to-solid ratio during the leaching process is 0.5 mL / g to 5 mL / g, and considering the processing cost, it can be further reduced to 1 mL / g to 2 mL / g.

[0024] In this invention, the final pH of the leaching is 6-8.

[0025] In this invention, alkali metals can be recovered from aqueous leachates using known methods. For example, the steps may include: introducing CO2 into the aqueous leachate or adding a water-soluble alkali metal carbonate (such as potassium carbonate or sodium carbonate) for impurity removal, wherein the CO2 flow rate is 0.2 L / min to 1 L / min, and the gas introduction time is 15 min to 45 min; the amount of potassium carbonate or sodium carbonate added is equal to the amount of Ca in the filtrate. 2+ The molar ratio is 1:1 to 1:1.2; subsequently, the purified water leachate is subjected to evaporation and crystallization treatment to recover the alkali metal salt. Alternatively, a condensation recovery device can be used to recover water vapor during the evaporation and crystallization process.

[0026] In this invention, lead-rich lead chloride ore leaching residue is subjected to acid dissolution treatment, followed by solid-liquid separation to obtain a lead-rich solution. The lead-rich solution is then subjected to sulfation precipitation to obtain lead sulfate product. The acid used for acid dissolution treatment can be at least one of HNO3, HClO4, and HF.

[0027] This invention removes impurity ions from the water leaching solution through aging and purification, recovers potassium chloride and sodium chloride crystals through evaporation and crystallization, and simultaneously recovers lead by washing the water leaching residue with weakly acidic water. The conditioning agent involved in this invention requires a small dosage, has low cost, and minimal environmental impact, providing a new technical path for the resource-based treatment of steel metallurgical dust in steel plants.

[0028] In this invention, the high Cl content of the aqueous leaching solution is utilized.- The environment is modified by adding conditioning agents to induce lead to form hydroxyl chloride ore to avoid K + The accompanying sedimentation. And the OH- released by the conditioning agent... - It does not participate in the leaching reaction of alkali metals, so this method differs from the traditional alkali extraction process. Only 0.5% to 3% of the weight of the iron and steel metallurgical dust needs to be added as a conditioning agent. Moreover, the pH of the solution is basically in a weakly alkaline to neutral environment during the water leaching process.

[0029] Beneficial effects

[0030] This invention eliminates the need for pretreatment of steelmaking dust, allowing direct water leaching with a conditioning agent. This enables deep leaching of potassium and sodium in a short time, while synergistically converting lead into its constituent forms. The invention achieves selective lead recovery and synergistic leaching of alkali metals through the selective conversion of lead into its hydroxyl chloride mineral phase and the leaching of alkali metals. This not only facilitates selective lead recovery but also improves the deep leaching of alkali metals. Studies show that the potassium and sodium removal rates of this invention can reach over 95%, with alkali metal residues in the water leaching residue being less than 1.0 wt%. Under the same conditions, compared to conventional water leaching without a conditioning agent, the method proposed in this invention increases potassium removal rate by over 15% and reduces alkali metal residues in the leached residue by over 85%.

[0031] This invention also shows that using synergistically combined alkaline earth metal-based materials as conditioning agents, and combinations of alkaline earth metal-based materials and alkali metal-based materials as conditioning agents, can further synergistically promote the dissolution of potassium and sodium. Attached Figure Description

[0032] Figure 1 The image shows the XRD pattern of the steel metallurgical dust used in Example 1.

[0033] Figure 2 The residual potassium / sodium content and removal rate in the water leaching residue of Example 1 and Comparative Example 1;

[0034] Figure 3 The phase composition of the water-leached residue from Example 1;

[0035] Figure 4 The phase composition of the water-leached residue of Comparative Example 1 is shown.

[0036] Figure 5 The residual potassium / sodium content and removal rate in the water leaching residue of Example 2;

[0037] Figure 6 This is a schematic diagram of the total resource recycling process in Example 4. Detailed Implementation

[0038] The present invention will be further described in detail below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] To avoid repetition, the raw materials involved in this specific embodiment are described uniformly as follows, and will not be repeated in the specific embodiments:

[0040] The steel metallurgical dust used in the implementation can be sintering machine head ash, and its XRD pattern can be found in [reference needed]. Figure 1 The iron content is 23±1wt%, the potassium content is 18±1wt%, the sodium content is 1.6±0.2wt%, the lead content is 3±1wt%, the chlorine content is 21±1wt%, and the sulfur content is 1wt%~2wt%.

[0041] The iron-bearing phases include Fe2O3 and Fe3O4, with Fe3O4 accounting for 50wt% to 60wt% of the Fe phase; the potassium-bearing phases include KCl and K2SO4, with KCl accounting for 90wt% to 95wt% of the K phase; the sodium-bearing phases include NaCl and Na2SO4, with NaCl accounting for 80wt% to 90wt% of the Na phase; and the PbCl2 content is 75wt% to 80wt% of the total Pb weight.

[0042] The specific implementation of this invention is as follows: Appropriate amounts of iron and steel metallurgical dust, conditioning agent, and deionized water are weighed according to a set ratio and placed in a reaction vessel. A mechanical stirring leaching reaction is then carried out at a set temperature for a period of time, with an appropriate stirring speed. After the leaching reaction is completed, the leachate and residue (water-leached residue) are separated using suction filtration or pressure filtration. The water-leached residue is then digested using a mixed acid (e.g., a mixed acid aqueous solution of HNO3, HClO4, and HF in a volume ratio of 5:3:2), and the potassium and sodium content is detected by atomic absorption spectrometry.

[0043] The removal rates of potassium and sodium (also known as leaching rates) are calculated using the following formula:

[0044] ;

[0045] In the formula: η is the metal removal rate, m0 is the mass of the iron and steel metallurgical dust before water immersion, ω0 is the potassium / sodium content in the iron and steel metallurgical dust, and m i It is the quality of the water-leached residue, ω i It refers to the potassium / sodium content in the water-leached residue.

[0046] In this invention, the residual amount in the water-leached residue refers to the weight percentage of sodium or potassium elements, and the removal rate is calculated from the residual amount.

[0047] In this invention, the room temperature is, for example, 25~30℃.

[0048] Example 1

[0049] Calcium oxide, potassium carbonate, and calcium hydroxide were added in a mass ratio of 8:1:1, and the mixture was mechanically activated at room temperature for 5 minutes to prepare a conditioning agent with good dispersibility and activity.

[0050] At room temperature, take an appropriate amount of iron and steel metallurgical dust (sintering machine head ash) with a liquid-to-solid ratio of 1.5 mL / g and a conditioning agent dosage of 2.6% of the mass of iron and steel metallurgical dust. Soak in water for 10 min under a stirring speed of 300 r / min. After the reaction, use vacuum filtration to separate the solid and liquid, and obtain water-soaked liquid and water-soaked residue.

[0051] The removal rates of Na and K and the residual amounts in the water-leached residue are shown in the figure. Figure 2 The phase composition of the water-leached residue is shown below. Figure 3 This indicates that hydroxyl chloride lead ore (its phase is Pb(OH)Cl) was successfully synthesized from water-leached residue.

[0052] The potassium content in the water-leached residue was measured to be 0.58 wt%, and the sodium content was 0.12 wt%. The calculated removal rates of potassium and sodium were 98.30% and 95.58%, respectively. The total residual alkali metal content in the water-leached residue was only 0.7 wt%, which is significantly better than existing technologies.

[0053] Comparative Example 1

[0054] Compared with Example 1, the only difference is that the conditioning agent is missing; all other operations and parameters are the same as in Example 1.

[0055] The recovery rates of Na and K in the water leaching solution and the residual amounts in the water leaching residue are shown in [reference needed]. Figure 2 XRD of the water-leached residue is shown in Figure 4 The results show that no hydroxyl chloride lead ore was induced in the water-leached residue.

[0056] The residual potassium content in the water-leached residue was determined to be 4.83 wt%, and the residual sodium content was 0.29 wt%. The calculated removal rates of potassium and sodium were only 84.54% and 88.34%, respectively. The residual alkali metal content in the water-leached residue was 5.12 wt%, which was too high to be returned to the sintering process.

[0057] Example 2

[0058] Compared with Example 1, the only difference is that the amount of quenching agent is changed. The amount of quenching agent added is 0.2wt%~5.0wt% of the mass of iron and steel metallurgical dust (group A: 0.2wt% of quenching agent; group B: 0.5wt% of quenching agent; group C: 1.0wt% of quenching agent; group D: 2.0wt% of quenching agent; group E: 5.0wt% of quenching agent). Other operations and parameters are the same as in Example 1.

[0059] The removal rates of Na and K in iron and steel metallurgical dust and their residual amounts in water-leached slag are shown in the figure. Figure 5 .

[0060] When the amount of conditioning agent added is 0.2% of the mass of iron and steel metallurgical dust, the residual amount of potassium in the water-leached slag is 1.87 wt% and the residual amount of sodium is 0.15 wt%; the calculated removal rate of potassium is 94.55% and the removal rate of sodium is 94.42%.

[0061] When the conditioned agent dosage was 0.5% of the mass of the iron and steel metallurgical dust, the removal effect of potassium and sodium reached its optimal level. The pH of the water leaching solution was 7.09, and the residual potassium content in the water leaching residue was 0.59 wt% and the residual sodium content was 0.15 wt%. The calculated removal rates of potassium and sodium were 98.27% and 94.63%, respectively. The residual alkali metal content in the water leaching residue was 0.74 wt%, which was still below 1 wt%.

[0062] Increasing the amount of quenching agent added to 1.0%, 2.0%, and 5.0% of the mass of the iron and steel metallurgical dust did not significantly improve the potassium removal effect. This indicates that the method of removing potassium and sodium from iron and steel metallurgical dust by adding quenching agent and water leaching, as adopted in this invention, requires a small amount of quenching agent; only 5 kg of quenching agent is needed to treat one ton of iron and steel metallurgical dust.

[0063] Example 3

[0064] Compared with Example 1, the only difference is that the type of conditioning agent is changed, the amount of conditioning agent is used, and other operations and parameters are the same as in Example 1. The experimental groups are as follows:

[0065] Group A: The conditioning agent is calcium oxide;

[0066] The potassium content in the water-leached residue was measured to be 1.14 wt%, and the sodium content was 0.14 wt%. The potassium removal rate was calculated to be 95.88%, and the sodium removal rate was 94.79%.

[0067] Group B: Change the conditioning agent to calcium hydroxide:

[0068] The potassium content in the water-leached residue was measured to be 1.38 wt%, and the sodium content was 0.2 wt%. The potassium removal rate was calculated to be 95.92%, and the sodium removal rate was 92.57%. The residual alkali metal content in the water-leached residue was 1.58 wt%.

[0069] Group C: The conditioning agent was changed to calcium oxide and calcium hydroxide in a weight ratio of 8:1.

[0070] The potassium content in the water-leached residue was measured to be 0.8 wt%, and the sodium content was 0.15 wt%. The potassium removal rate was calculated to be 97.69%, and the sodium removal rate was 94.56%. The residual alkali metal content in the water-leached residue was 0.95 wt%.

[0071] Group D: The conditioning agent was changed to calcium oxide and potassium carbonate in a weight ratio of 8:2.

[0072] The potassium content in the water-leached residue was measured to be 0.45 wt%, and the sodium content was 0.18 wt%. The potassium removal rate was calculated to be 98.70%, and the sodium removal rate was 93.45%. The residual alkali metal content in the water-leached residue was 0.63 wt%.

[0073] Group E: The conditioning agent is potassium carbonate;

[0074] The potassium content in the water-leached residue was measured to be 1.11 wt%, and the sodium content was 0.17 wt%. The potassium removal rate was calculated to be 96.76%, and the sodium removal rate was 93.76%. The residual alkali metal content in the water-leached residue was 1.28 wt%.

[0075] Example 4

[0076] The aqueous extract and aqueous residue were obtained using the leaching method of Group C in Example 2, and then... Figure 6 The schematic diagram shown undergoes further resource processing, the steps of which are as follows:

[0077] Step a: 99.5% pure CO2 is introduced into the aqueous leachate at a flow rate of 1.5 L / min. After no precipitate forms in the solution, the solution after liquid-solid separation (aged and purified solution) is placed in an evaporator and evaporated to dryness at 100 °C. The solution is then cooled to room temperature to obtain the alkali metal salt product. The solid obtained from the liquid-solid separation can be used in cement production.

[0078] Step b: Wash the water-leached residue with weakly acidic water (pH=5.0). After liquid-solid separation (pressure filtration), the obtained solid is iron-rich filter residue, which can be recycled back to the sintering / bulk reduction process. Additionally, add an appropriate amount of potassium sulfate (1-1.1 times the theoretical molar amount of lead precipitate) to the solution obtained from the pressure filtration. After standing for 10 minutes, perform solid-liquid separation using vacuum filtration to obtain lead sulfate product (lead product). The solution obtained during the vacuum filtration process (lead precipitate mother liquor) can be combined with the aging and impurity removal solution from step a and then subjected to evaporation and crystallization.

[0079] The alkali metal salt products were found to contain 47.75 wt% potassium, 46.38 wt% chlorine, and 2.70 wt% sodium. The potassium recovery rate was calculated to be 96.21%, and the product purity (based on potassium chloride) was over 90%. The lead sulfate product had a purity of over 90%, and the lead recovery rate was 82.52%.

[0080] Example 5

[0081] Compared with Example 1, the only difference is that MgO is used as the conditioning agent, while the amount of conditioning agent and other operations and parameters are the same as in Example 1.

[0082] The potassium content in the water-leached residue was measured to be 1.53 wt%, and the sodium content was 0.15 wt%. The potassium removal rate was calculated to be 95.61%, and the sodium removal rate was 94.01%. The residual alkali metal content in the water-leached residue was 1.68 wt%.

[0083] Comparative Example 2

[0084] Compared with Example 1, the only difference is that potassium hydroxide is used instead of the conditioning agent. The initial pH of the aqueous solution after adding the conditioning agent is the same as that in Example 1. All other operations and parameters are the same as in Example 1.

[0085] The residual potassium content in the water-leached residue was determined to be 2.95 wt%, and the residual sodium content was 0.16 wt%. The calculated removal rates for potassium and sodium were only 90.90% and 93.80%, respectively. The pH of the water-leached solution was 6.37. The residual alkali metal content in the water-leached residue was 3.11 wt%, which was too high to be returned to the sintering process.

[0086] Comparative Example 3

[0087] Compared to Example 1, the only difference is that the system was first soaked in water for 10 minutes without a conditioning agent, and then treated for another 10 minutes using potassium hydroxide (the initial pH of the aqueous solution after adding the conditioning agent was the same as in Example 1) as a conditioning agent. The difference in steps is as follows:

[0088] At room temperature, take an appropriate amount of iron and steel metallurgical dust and mix it with water at a liquid-to-solid ratio of 1.5 mL / g, and soak it in water for 10 min under a stirring speed of 300 r / min. After the reaction is complete, use potassium hydroxide (the amount is the same as in comparative example 2), and then continue stirring for 10 min.

[0089] The residual potassium content in the water-leached residue was determined to be 1.50 wt%, and the residual sodium content was 0.14 wt%. The calculated removal rates of potassium and sodium were 95.50% and 94.70%, respectively. The residual alkali metal content in the water-leached residue was 1.64 wt%.

Claims

1. A method for recovering metallurgical dust containing lead and alkali metal elements, characterized in that, Metallurgical dust containing lead and alkali metal elements, along with a conditioning agent, is leached in water to dissolve the alkali metal elements in the metallurgical dust and convert the lead elements into hydroxyl chloride precipitate. Subsequently, solid-liquid separation is performed to obtain an aqueous leaching solution enriched with alkali metals and an aqueous leaching residue containing hydroxyl chloride precipitate. The conditioning agent comprises calcium oxide and calcium hydroxide in a weight ratio of 5 to 10:1; or, the conditioning agent comprises alkaline earth metal-based materials and alkali metal-based materials; wherein the weight ratio of alkaline earth metal-based materials and alkali metal-based materials is 5 to 10:

1. The alkaline earth metal-based material is at least one of calcium oxide and hydroxide; the alkali metal-based material is at least one of alkali metal carbonate, bicarbonate, and carboxylate. Alkali metals include at least one element selected from sodium and / or potassium; In the metallurgical dust containing lead and alkali metal elements, the lead-bearing phase includes PbCl2; the alkali metal-bearing phase includes at least one of alkali metal chloride and alkali metal sulfate; wherein the lead content is 2wt%~10wt%, the alkali metal content is 5wt%~40wt%, and the chlorine content is 10wt%~30wt%. The conditioning agent is 0.5% to 3% by weight of metallurgical dust containing lead and alkali metal elements.

2. The method for recovering metallurgical dust containing lead and alkali metal elements as described in claim 1, characterized in that, The metallurgical dust containing lead and alkali metal elements contains the following components and contents: iron 20wt%~30wt%, potassium 15wt%~20wt%, sodium 1.0wt%~2wt%, lead 4wt%~6wt%, chlorine 20wt%~22wt%, and sulfur 1wt%~2wt%. The iron-bearing phases include Fe2O3 and Fe3O4, with Fe3O4 accounting for 50wt%~60wt% of the Fe phase. The potassium-bearing phases include KCl and K2SO4, with KCl accounting for 90wt%~95wt% of the K phase. The sodium-bearing phases include NaCl and Na2SO4, with NaCl accounting for 80wt%~90wt% of the Na phase. The PbCl2 content is 75wt%~80wt% of the total Pb weight.

3. The method for recovering metallurgical dust containing lead and alkali metal elements as described in claim 1, characterized in that, The conditioning agent is 0.5% to 1% of the weight of metallurgical dust containing lead and alkali metal elements.

4. The method for recovering metallurgical dust containing lead and alkali metal elements as described in claim 1, characterized in that, The temperature during the leaching process is 0 ℃~60 ℃; The leaching time is 1 min to 60 min; The liquid-to-solid ratio during the leaching process is 0.5 mL / g to 5 mL / g.

5. The method for recovering metallurgical dust containing lead and alkali metal elements as described in claim 1, characterized in that, The alkali metal product is obtained by passing CO2 into the aqueous leaching solution or by adding water-soluble alkali metal carbonates for impurity removal, followed by evaporation.

6. The method for recovering metallurgical dust containing lead and alkali metal elements as described in claim 1, characterized in that, The lead-rich hydroxychlorolead ore leaching residue is acid-dissolved, followed by solid-liquid separation to obtain a lead-rich solution. The lead-rich solution is then sulfated to precipitate lead sulfate product.

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