Method for producing calcium carbonate from yellow phosphorus waste secondary carbonized solid calcium

Abstract

The invention belongs to the technical field of comprehensive utilization of resources and preparation of inorganic materials, and particularly relates to a method for producing calcium carbonate from yellow phosphorus waste secondary carbonized solid calcium. According to the method, by-products phosphorus slag and yellow phosphorus tail gas in the yellow phosphorus production process are used as main raw materials, and efficient extraction of calcium and green preparation of nanoscale calcium carbonate are achieved through the process steps of organic complexing agent activation, impurity coprecipitation control, wet-process calcium extraction, carbonization reaction, surfactant regulation and control and the like. The method comprises the following steps: firstly, mixing and activating phosphorus slag and an organic complexing agent, then leaching with an ammonium salt solution under the action of an impurity coprecipitation control agent, and reacting filtrate with CO2 in tail gas to precipitate calcium carbonate. The whole-flow process is low in energy consumption, high in raw material utilization rate, small in particle size and high in purity of the obtained calcium carbonate, environment-friendly in process, excellent in product quality and suitable for high-end fields of plastics, rubber, printing ink and the like.

Description

Technical Field

[0001] This invention belongs to the field of comprehensive resource utilization and inorganic material preparation technology, and particularly relates to a method for producing calcium carbonate from waste yellow phosphorus carbonation. Background Technology

[0002] The traditional electrothermal method for producing yellow phosphorus generates a large amount of byproducts and waste, mainly including phosphorus slag and yellow phosphorus tail gas. Phosphorus slag is a solid waste emitted after the high-temperature reaction during yellow phosphorus production. Its main components are calcium oxide and silicon dioxide, along with impurities such as fluorine, iron, and aluminum. Due to its large production volume and stable properties, phosphorus slag has long been primarily stored in the open, leading to multiple pressures including land occupation and environmental pollution. Especially under conditions of rainfall and long-term accumulation, harmful elements in the phosphorus slag gradually leach out, threatening soil and groundwater safety. With the increasing national requirements for solid waste disposal and environmental protection, the harmless and resource-based utilization of yellow phosphorus slag has become a pressing problem for the industry.

[0003] Meanwhile, the exhaust gas produced during yellow phosphorus production also faces similarly severe environmental challenges. The main component of yellow phosphorus exhaust gas is carbon monoxide, along with various impurities such as carbon dioxide, methane, sulfides, phosphorus, and its compounds. This exhaust gas is difficult to purify, poses numerous safety hazards, and direct emission can easily cause environmental pollution. Currently, the main method of utilizing this exhaust gas is to use it as fuel for boiler power generation after simple purification. This approach neither achieves efficient resource utilization of the exhaust gas nor generates significant economic benefits, resulting in persistently high carbon emissions and a prominent problem of resource waste.

[0004] On the other hand, calcium carbonate, as a high-value-added new material, has been widely used in various industries such as plastics, rubber, coatings, and inks in recent years due to its small particle size, good dispersibility, and significant surface effect. Most existing mainstream calcium carbonate production processes use natural limestone as raw material, preparing lime through high-temperature calcination, followed by digestion and carbonation reactions to obtain the finished calcium carbonate product. While these processes are relatively mature, they generally suffer from prominent problems such as high energy consumption, large carbon dioxide emissions, and rising raw material costs. Especially under the background of carbon peaking and carbon neutrality, the industry urgently needs to develop new green, low-carbon, and lower-cost production routes to meet the needs of sustainable industrial development.

[0005] In summary, the current yellow phosphorus industry faces significant shortcomings in the high-value utilization of by-product phosphorus slag and tail gas, as well as in the green and low-carbon manufacturing of calcium carbonate. The substantial idleness of phosphorus slag and tail gas resources not only increases the environmental burden but also hinders the high-quality development of the yellow phosphorus industry. Simultaneously, the high energy consumption and cost of calcium carbonate production make it difficult to meet the industry's dual requirements for energy conservation, emission reduction, and economic efficiency. Therefore, there is an urgent need to develop a new process and pathway that enables the synergistic utilization of phosphorus slag and yellow phosphorus tail gas, and can produce calcium carbonate in a green and efficient manner, in order to promote the sustainable development of the yellow phosphorus industry and related downstream materials industries. Summary of the Invention

[0006] The purpose of this invention is to provide a method for producing calcium carbonate from waste carbonization and solidification of yellow phosphorus, aiming to achieve efficient and synergistic utilization of by-product phosphorus slag and tail gas during the production of yellow phosphorus. This method prepares high-quality calcium carbonate through a green and low-carbon process, which not only effectively reduces resource waste and environmental pressure, but also enhances product added value and overall economic benefits.

[0007] To achieve the above objectives, the present invention provides the following technical solution: A method for producing calcium carbonate from waste carbonized yellow phosphorus includes the following steps: (1) The phosphorus slag produced as a by-product in the production of yellow phosphorus is mixed with an organic complexing agent and ground to obtain activated phosphorus slag; (2) The activated phosphorus slag and ammonium salt solution are mixed at a solid-liquid mass ratio of 1:5-30, and an impurity co-precipitation control agent is added. The mixture is reacted to obtain a slurry. The impurity coprecipitation control agent is a compound of aluminum sulfate, ferrous sulfate and disodium hydrogen phosphate, with a mass ratio of 1:(0.5-2):(0.2-1). (3) Separate the slurry into solid and liquid components to obtain filtrate and filter cake; (4) The filtrate is mixed with the CO2-containing waste flue gas obtained after the yellow phosphorus tail gas is treated by combustion and heat recovery, and carbonization reaction is carried out. During the carbonization reaction, a surfactant is added to the system, and calcium carbonate slurry is obtained after the reaction. (5) The calcium carbonate slurry is subjected to solid-liquid separation to obtain a wet filter cake of calcium carbonate. The wet filter cake is washed with water and dried to obtain the calcium carbonate product.

[0008] In the industrial production of yellow phosphorus, the production of 1 ton of yellow phosphorus typically generates 8 to 10 tons of phosphorus slag as a byproduct. The main chemical component of this slag is calcium oxide (CaO), with a content of 45%–50%; it also contains 0.5%–1.5% magnesium oxide (MgO), 35%–40% silicon dioxide (SiO2), 2%–2.2% fluorine (F), 0.5%–1.0% ferric oxide (Fe2O3), and 0.5%–1.5% aluminum oxide (Al2O3). Simultaneously, each ton of yellow phosphorus also generates approximately 2500–3000 standard cubic meters of yellow phosphorus tail gas. The main gaseous component of this tail gas is carbon monoxide (CO), with a content as high as 85%–90%, and it also contains 0%–2% carbon dioxide (CO2), 0%–2% methane (CH4), and 1000–3000 mg / Nm³. 3 Sulfides and 1000–3000 mg / Nm 3 Phosphorus and phosphides, with other impurities ranging from 0% to 5%.

[0009] Furthermore, the ammonium salt is ammonium nitrate or ammonium chloride.

[0010] Furthermore, the phosphorus slag produced as a byproduct in the yellow phosphorus production process described in step (1) is mixed with an organic complexing agent and ground so that more than 95% of the particles can pass through a 100-mesh sieve.

[0011] Further, the organic complexing agent in step (1) is composed of triethanolamine, ammonium fluorosilicate and ammonium sulfate in a mass ratio of (0.05-0.15):(0.1-0.3):(1-2).

[0012] Further, the amount of organic complexing agent added in step (1) is 0.5-5% of the mass of the phosphorus slag.

[0013] In this method, adding an organic complexing agent to the phosphorus slag promotes the release of the calcium phase. Some calcium in the phosphorus slag exists as inclusions or dense minerals, making it difficult to achieve sufficient leaching through conventional physical grinding and direct solvent treatment. The organic complexing agent can form stable, soluble complexes with calcium ions, disrupting the structural inclusions between calcium and impurities such as silicon, increasing the calcium reaction interface, and improving the calcium extraction rate during subsequent reactions with ammonium salts. Simultaneously, the organic complexing agent has a buffering effect on the system pH, helping to inhibit the dissolution of some impurity elements, thereby improving the separation efficiency of calcium and impurities in the filtrate and reducing the impact of impurities on subsequent carbonization reactions and product purity. Furthermore, the complexing agent's role in promoting calcium phase dissolution can reduce the required reaction temperature and time, improving the overall process efficiency.

[0014] Further, the amount of impurity co-precipitation control agent used in step (2) is 0.1-2% of the mass of the phosphorus slag. Further, in step (2), the mass concentration of the ammonium salt solution is 5-30%, the reaction temperature is 50-200℃, the reaction time is 30-180 minutes, the reaction pressure is 0.05-1.2MPa, and the reaction is carried out under stirring and ultrasonic conditions.

[0015] The main function of the impurity co-precipitation control agent in this method is to preferentially capture and precipitate impurities such as phosphorus and fluorine associated with phosphorus slag, thereby effectively improving the purity of calcium in the filtrate. Specifically, the aluminum and iron ions generated after the hydrolysis of aluminum sulfate and ferrous sulfate in solution can form insoluble phosphate and fluoride precipitates with impurities such as phosphate and fluoride ions, allowing these impurities to be preferentially removed and enriched in the solid phase. The addition of disodium hydrogen phosphate can adjust the phosphate concentration in the solution, further enhancing the co-precipitation efficiency of impurities and the trapping agent. In this way, the impurity content in the solution can be effectively reduced without significantly affecting the leaching of calcium ions, creating a purer calcium source environment for subsequent carbonation reactions, reducing the entrainment of impurities in the calcium carbonate product, and improving product purity and quality.

[0016] The activated phosphorus slag reacts with an ammonium salt solution, causing the calcium phase to dissolve and calcium ions to enter the liquid phase. On the other hand, metal ions in the added co-precipitation control agent react with impurity ions, such as Al, to undergo precipitation. 3+ Fe 2+ With PO4 in solution 3- F - This process forms insoluble precipitates such as AlPO4, FePO4, AlF3, and FeF3. By selectively precipitating impurities, this process improves the separation of calcium from impurities in solution, thereby increasing the purity and process controllability of subsequent calcium carbonate precipitation.

[0017] Furthermore, the filter cake in step (3) is washed with water. The washed filter cake is rich in active silicon and fluorine and can be used as a cement, building material or chemical raw material for comprehensive utilization. The washing liquid obtained after washing is collected and recycled for carbonization reaction in step (4).

[0018] Further, the surfactant in step (4) is sodium dodecylbenzenesulfonate or polyvinyl alcohol, and the amount of surfactant used is 0.01-0.2% of the mass of the filtrate.

[0019] Further, in step (4), the molar ratio of calcium ions to CO2 in the filtrate is 1:(1-2); the carbonization reaction time is 30-120 minutes.

[0020] This step utilizes the filtrate obtained from solid-liquid separation to mix with CO2-containing waste gas obtained after combustion and heat recovery treatment of yellow phosphorus tail gas for a carbonization reaction. The Ca in the solution... 2+It reacts with CO2 gas to form insoluble calcium carbonate precipitate. During the carbonation reaction, the addition of an appropriate amount of surfactant can significantly improve the dispersibility and particle size uniformity of the formed calcium carbonate crystals. Surfactants can adsorb onto the crystal surface during calcium carbonate nucleation and growth, reducing the surface energy between crystal grains, inhibiting particle agglomeration and irregular growth, and promoting the formation of uniform, small-sized, and well-dispersed nano-sized calcium carbonate. This not only improves the product's flowability and processability but also facilitates subsequent separation and drying processes.

[0021] Furthermore, the drying in step (5) is carried out using the residual heat obtained after the yellow phosphorus tail gas is burned or the heat energy is recovered; the filtrate after solid-liquid separation in step (5) is concentrated and then returned to step (2) for recycling.

[0022] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows: 1. The technical solution of this invention achieves high-value conversion of industrial waste that was originally difficult to utilize by means of phosphorus slag and tail gas in the production of yellow phosphorus, and has significant advantages in terms of energy saving, environmental protection and energy consumption reduction. First, the process uses phosphorus slag as the main raw material, without relying on purchased natural limestone and other mineral resources, which greatly improves the utilization efficiency of waste residue and reduces the risk of solid waste accumulation and environmental pollution. After combustion and heat recovery treatment, the yellow phosphorus tail gas is used as a CO2 gas source for carbonization reaction, replacing purchased or energy-intensive industrial CO2, realizing the direct resource utilization of carbon source in tail gas, and reducing overall carbon emissions and greenhouse gas release. The process uses the recovery, concentration and recycling of washing liquid and filtrate, which not only significantly reduces the consumption of fresh water and chemicals, but also minimizes the amount of wastewater discharged. The waste heat of yellow phosphorus tail gas is used for calcium carbonate drying, which fully recovers the process heat energy and effectively reduces system energy consumption. Overall, this technical solution significantly improves resource utilization and process economy through the tiered utilization of raw materials, energy recovery, closed-loop recycling, and comprehensive development of by-products, and has remarkable characteristics of being green, low-carbon, and highly efficient.

[0023] 2. This invention effectively improves the preparation efficiency and product quality of calcium carbonate by introducing process measures such as activation treatment with organic complexing agents, impurity co-precipitation control, and surfactant regulation. Activation treatment promotes the full release of the calcium phase in phosphorus slag, increasing the calcium extraction rate and providing a high-concentration calcium source with few impurities for subsequent carbonation reactions. The optimized use of impurity co-precipitation control agents effectively reduces the residue of impurities such as phosphorus and fluorine in the solution and final product, significantly improving the purity of calcium carbonate. The appropriate addition of surfactants during the carbonation reaction results in finer and more uniformly distributed calcium carbonate crystals, inhibiting particle agglomeration and obtaining nano-sized calcium carbonate products with good dispersibility and easy separation. The process parameters are easily controllable throughout the process, and the resulting calcium carbonate has high purity, high specific surface area, and excellent dispersibility, meeting the application requirements of high-end fields such as plastics, inks, and rubber. Attached Figure Description

[0024] Figure 1 The image shows a scanning electron microscope image of calcium carbonate prepared in Example 1.

[0025] Figure 2 The image shows a scanning electron microscope image of calcium carbonate prepared in Example 2.

[0026] Figure 3 The image shows a scanning electron microscope image of calcium carbonate prepared in Example 3.

[0027] Figure 4 The image shows a scanning electron microscope image of calcium carbonate prepared in Example 4.

[0028] Figure 5 This is a scanning electron microscope image of calcium carbonate prepared in Example 5.

[0029] Figure 6 The image shows a scanning electron microscope image of calcium carbonate prepared in Example 6.

[0030] Figure 7 The image shows a scanning electron microscope image of calcium carbonate prepared in Example 7.

[0031] Figure 8 Scanning electron microscope image of calcium carbonate prepared for Comparative Example 1.

[0032] Figure 9 Scanning electron microscope image of calcium carbonate prepared for Comparative Example 2.

[0033] Figure 10 Scanning electron microscope image of calcium carbonate prepared for Comparative Example 3.

[0034] Figure 11 Scanning electron microscope image of calcium carbonate prepared for Comparative Example 4.

[0035] Figure 12Scanning electron microscope image of calcium carbonate prepared for Comparative Example 5.

[0036] Figure 13 Scanning electron microscope image of calcium carbonate prepared for Comparative Example 6. Detailed Implementation

[0037] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0038] Unless otherwise specified, all raw materials used in the examples are commercially available products.

[0039] The main chemical components of the phosphorus slag used in this embodiment of the invention are: 48% calcium oxide (CaO), 1.0% magnesium oxide (MgO), 37% silicon dioxide (SiO2), 2.1% fluorine (F), 0.7% ferric oxide (Fe2O3), 1.2% aluminum oxide (Al2O3), and the remainder are insoluble residues and trace impurities.

[0040] Example 1 This embodiment provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus, including the following steps: (1) Add an organic complexing agent to the phosphorus slag. The composition of the organic complexing agent by mass is: 0.1 parts of triethanolamine, 0.2 parts of ammonium fluorosilicate, and 1.5 parts of ammonium sulfate. The mass of the organic complexing agent is 2.5% of the phosphorus slag. Grind the mixture so that more than 95% of the particles can pass through a 100-mesh sieve to complete the activation treatment and obtain activated phosphorus slag.

[0041] (2) The activated phosphorus slag obtained in step (1) is mixed with ammonium nitrate solution at a solid-liquid mass ratio of 1:20. The mass concentration of the ammonium nitrate solution is 18%. Then, an impurity coprecipitation control agent is added. The composition of the impurity coprecipitation control agent by mass is: 1 part aluminum sulfate, 1 part ferrous sulfate, and 0.5 parts disodium hydrogen phosphate. The total amount of the coprecipitation control agent accounts for 1% of the mass of the phosphorus slag. The mixed system is subjected to ultrasound and stirred at 55°C for 90 minutes to promote the full leaching of calcium and the removal of impurities through coprecipitation.

[0042] (3) The reaction slurry obtained in step (2) is subjected to solid-liquid separation to obtain filtrate and filter cake. The filter cake is washed with water, and each wash is stirred for 10 minutes before filtration. All washing liquid is collected and concentrated to 1 / 3 of its original volume.

[0043] (4) The filtrate and washing liquid obtained in step (3) are put into the reactor, and the waste gas containing CO2 obtained after the yellow phosphorus tail gas has been treated by combustion and heat recovery is introduced to control the Ca 2+ The molar ratio of sodium dodecylbenzenesulfonate to CO2 was 1:1.5, the reaction temperature was maintained at 50℃, and the reaction time was 60 minutes. Sodium dodecylbenzenesulfonate surfactant was added at the beginning of the reaction, at an amount of 0.1% of the filtrate mass, and the reaction was stirred to carbonize and produce a calcium carbonate slurry.

[0044] (5) The calcium carbonate slurry is subjected to solid-liquid separation to obtain a wet filter cake. The wet filter cake is washed twice with process water, and filtered after thorough stirring each time. The washed wet filter cake is sent to a drying device and dried with hot air output from the yellow phosphorus tail gas through a heat recovery device to finally obtain a high-purity calcium carbonate product.

[0045] Example 2 This embodiment provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus. The difference from Embodiment 1 is that the composition of the organic complexing agent in step (1) is: 0.05 parts of triethanolamine, 0.2 parts of ammonium fluorosilicate, and 2 parts of ammonium sulfate.

[0046] Example 3 This embodiment provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus. The difference from Embodiment 1 is that the composition of the organic complexing agent in step (1) is: 0.15 parts of triethanolamine, 0.2 parts of ammonium fluorosilicate, and 1 part of ammonium sulfate.

[0047] Example 4 This embodiment provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus. The difference from Embodiment 1 is that the total amount of the impurity coprecipitation control agent in step (2) accounts for 2% of the mass of phosphorus slag.

[0048] Example 5 This embodiment provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus. The difference from Embodiment 1 is that the total amount of the impurity coprecipitation control agent in step (2) accounts for 0.1% of the mass of phosphorus slag.

[0049] Example 6 This embodiment provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus. The difference from Embodiment 1 is that, by mass, the composition of the impurity coprecipitation control agent in step (2) is: 1 part aluminum sulfate, 0.5 parts ferrous sulfate, and 1 part disodium hydrogen phosphate.

[0050] Example 7 This embodiment provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus. The difference from Embodiment 1 is that in step (4), the surfactant is replaced with polyvinyl alcohol, and the amount added is 0.01% of the mass of the filtrate.

[0051] Comparative Example 1 This comparative example provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus. The difference from Example 1 is that in step (1), triethanolamine is replaced with sodium ethylenediaminetetraacetate.

[0052] Comparative Example 2 This comparative example provides a method for producing calcium carbonate from waste carbonized yellow phosphorus, which differs from Example 1 in that: in step (1), ammonium sulfate is replaced with citric acid.

[0053] Comparative Example 3 This comparative example provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus. The difference from Example 1 is that, by mass, the composition of the impurity coprecipitation control agent in step (2) is: 1 part aluminum sulfate, 1 part ferrous sulfate, and 2 parts disodium hydrogen phosphate.

[0054] Comparative Example 4 This comparative example provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus. The difference from Example 1 is that the composition and ratio of the impurity coprecipitation control agent in step (2) are: 1 part copper sulfate, 1 part ferrous sulfate, and 0.5 parts disodium hydrogen phosphate.

[0055] Comparative Example 5 This comparative example provides a method for producing calcium carbonate from waste carbonized calcium from yellow phosphorus. The difference from Example 1 is that, by mass, the composition of the impurity coprecipitation control agent in step (2) is: 1 part aluminum sulfate, 1 part ferrous sulfate, and 0.5 parts sodium hydroxide.

[0056] Comparative Example 6 This comparative example provides a method for producing calcium carbonate from waste carbonized solid calcium from yellow phosphorus. The difference from Example 1 is that in step (4), sodium dodecylbenzenesulfonate is replaced with sodium carboxymethyl cellulose.

[0057] Performance testing The product yield (%), particle size (D50, nm) and CaCO3 purity (%) of the calcium carbonate prepared in Examples 1-7 and Comparative Examples 1-6 were tested respectively, and the results are shown in Table 1.

[0058] Scanning electron microscope (SEM) images of calcium carbonate prepared in Examples 1-7 and Comparative Examples 1-6 are shown below. Figure 1-13 As shown.

[0059] Table 1 Performance Test Results

[0060] The above results show that Examples 1-7 can stably produce calcium carbonate products with high yield, concentrated particle size distribution, and excellent purity. The yield of all examples is above 83%, the D50 particle size is controlled between 75-87 nm, the product purity is above 97%, and the products are all well-dispersible white powders. This indicates that the technical solution of this invention can efficiently utilize yellow phosphorus by-product waste to obtain high-purity and high-quality nano-sized calcium carbonate, with good process controllability and product consistency.

[0061] Comparative Examples 1 and 2, by replacing the composition of the organic complexing agent, resulted in weaker selective complexation of calcium in phosphorus slag, significant co-dissolution of impurities, low product yield, larger particle size, decreased purity, and significant product agglomeration. In Comparative Example 3, the excessively high proportion of disodium hydrogen phosphate led to an imbalance in the precipitant, resulting in insufficient impurity precipitation, increased impurity residue, larger product particle size, and lower purity. Comparative Example 4, using copper sulfate instead of aluminum sulfate, resulted in poorer impurity co-precipitation, increased metal impurity entrainment, decreased product yield and purity, and larger particle size. Comparative Example 5, using sodium hydroxide instead of disodium hydrogen phosphate, increased the alkalinity of the reaction system, increased side reactions, and made it difficult to effectively remove impurities, leading to increased product particle size and impurities, as well as a decrease in yield. Comparative Example 6, using sodium carboxymethyl cellulose as a surfactant, resulted in poorer dispersion, increased calcium carbonate particle size and agglomeration, and a slight decrease in purity.

[0062] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for producing calcium carbonate from waste carbonized yellow phosphorus, comprising the following steps: (1) The phosphorus slag produced as a by-product in the production of yellow phosphorus is mixed with an organic complexing agent and ground to obtain activated phosphorus slag; (2) The activated phosphorus slag and ammonium salt solution are mixed at a solid-liquid mass ratio of 1:5-30, and an impurity co-precipitation control agent is added. The mixture is reacted to obtain a slurry. The impurity coprecipitation control agent is a compound of aluminum sulfate, ferrous sulfate and disodium hydrogen phosphate, with a mass ratio of 1:(0.5-2):(0.2-1). (3) Separate the slurry into solid and liquid components to obtain filtrate and filter cake; (4) The filtrate and the waste gas containing CO2 obtained after combustion and heat recovery treatment of yellow phosphorus tail gas are subjected to carbonization reaction. During the carbonization reaction, a surfactant is added to the system, and calcium carbonate slurry is obtained after the reaction. (5) The calcium carbonate slurry is subjected to solid-liquid separation to obtain a wet filter cake of calcium carbonate. The wet filter cake is washed with water and dried to obtain the calcium carbonate product.

2. The method for producing calcium carbonate from yellow phosphorus waste carbonization according to claim 1, characterized in that, In step (1), the phosphorus slag produced as a by-product during the production of yellow phosphorus is mixed with an organic complexing agent and ground so that more than 95% of the particles can pass through a 100-mesh sieve.

3. The method for producing calcium carbonate from yellow phosphorus waste carbonization according to claim 1, characterized in that, The organic complexing agent in step (1) is composed of triethanolamine, ammonium fluorosilicate and ammonium sulfate in a mass ratio of (0.05-0.15):(0.1-0.3):(1-2).

4. The method for producing calcium carbonate from yellow phosphorus waste carbonization according to claim 3, characterized in that, The amount of organic complexing agent added in step (1) is 0.5-5% of the mass of the phosphorus slag.

5. The method for producing calcium carbonate from yellow phosphorus waste carbonization according to claim 1, characterized in that, The amount of impurity coprecipitation control agent used in step (2) is 0.1-2% of the mass of the phosphorus slag.

6. The method for producing calcium carbonate from yellow phosphorus waste carbonization according to claim 1, characterized in that, In step (2), the mass concentration of the ammonium salt solution is 5-30%, the reaction temperature is 50-200℃, the reaction time is 30-180 minutes, the reaction pressure is 0.05-1.20 MPa, and the reaction is carried out under stirring and ultrasonic conditions.

7. The method for producing calcium carbonate from yellow phosphorus waste carbonization according to claim 1, characterized in that, The filter cake in step (3) is washed with water. The washed filter cake is then used as a cement, building material or chemical raw material for comprehensive utilization. The washing liquid obtained after washing is collected and recycled for carbonization reaction in step (4).

8. The method for producing calcium carbonate from yellow phosphorus waste carbonization according to claim 1, characterized in that, The surfactant used in step (4) is sodium dodecylbenzenesulfonate or polyvinyl alcohol, and the amount of surfactant used is 0.01-0.2% of the mass of the filtrate.

9. The method for producing calcium carbonate from yellow phosphorus waste carbonization according to claim 1, characterized in that, In step (4), the molar ratio of calcium ions to CO2 in the filtrate is 1:(1-2); the carbonization reaction takes 30-120 minutes.

10. The method for producing calcium carbonate from yellow phosphorus waste carbonization according to claim 1, characterized in that, The drying in step (5) uses the residual heat obtained after the yellow phosphorus tail gas is burned or the heat energy is recovered for drying; the filtrate after solid-liquid separation in step (5) is concentrated and then returned to step (2) for recycling.

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