Method and system for harmless disposal and classified resource utilization of organic silicon slurry residue and waste catalyst

Abstract

The application provides a method and system for harmless treatment and resource utilization of organic silicon slurry residue and waste contact body, and belongs to the technical field of metal refining. Part of the grinding hydrolysate, part of the heap leaching liquid and the organic silicon slurry residue are hydrolyzed to obtain grinding hydrolysate and hydrolysis residue powder. The hydrolysis residue powder is subjected to heap leaching to obtain heap leaching liquid and heap leaching solid residue. The heap leaching liquid is reduced by iron powder to obtain sponge copper, and then subjected to extraction and back extraction, and then subjected to electrodeposition to obtain metallic copper. The heap leaching liquid is subjected to extraction and back extraction, and then subjected to electrodeposition to obtain metallic zinc. The heap leaching solid residue is subjected to dissolution and solid-liquid separation, and the obtained liquid phase is subjected to water washing and causticization reaction to prepare a sodium methyl silicate product. The liquid phase is subjected to water washing, water boiling activation, causticization and water addition to prepare a silica sol. The method and system realize resource utilization of all components of the organic silicon slurry residue and the waste contact body, and solve the problems of low resource utilization rate, more secondary three wastes and poor operation benefit of the existing organic silicon slurry residue and waste contact body treatment process in the industry.

Description

Technical Field

[0001] This invention relates to the technology for the resource utilization of organosilicon waste, and more particularly to a method and system for the harmless disposal and classified resource utilization of organosilicon slurry residue and waste catalyst. Background Technology

[0002] Organosilicon slurry residue and waste catalysts are the main byproducts of the direct synthesis of methylchlorosilanes, accounting for approximately 3-6% of the total methylchlorosilane production. The main components of organosilicon slurry residue and waste catalysts are ultrafine silica powder containing elements such as copper, zinc, and iron, and organochlorosilanes with boiling points greater than 80℃. With the rapid development of the organosilicon industry, the harmless and resource-based treatment processes for organosilicon slurry residue and waste catalysts have become a research hotspot in the organosilicon industry.

[0003] Currently, the main treatment processes for organosilicon slurry residue and waste catalysts include hydrolysis, incineration, and distillation. Hydrolysis is the most widely used process, but existing processes only utilize iron to replace copper sponge during metal element recovery, resulting in high copper ion levels in the wastewater. Furthermore, neutral and alkaline hydrolysis processes cannot recover hydrogen chloride, and the hydrolysis of organosilicon chlorosilanes forms a mixed solid slag of siloxanes and silicon powder. Since the siloxanes coat the silicon powder, there is currently no effective utilization pathway. Incineration can effectively recover hydrogen chloride, but the incineration temperature exceeds 1000℃, and metal element recovery is still incomplete. Organosilicon chlorosilanes can only be converted into silicon dioxide powder, resulting in low added value. Distillation can effectively separate silicon powder and organochlorosilanes, but organochlorosilanes have low methyl content and low-value disproportionation products. Further development of processes for the recovery and utilization of silicon powder and its contained metal elements is needed.

[0004] Therefore, there is currently no effective method for treating organosilicon slurry residue and waste catalysts, and for recovering metal elements, siloxanes, and silicon powder. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method and system for the harmless disposal and classified resource utilization of organosilicon slurry residue and waste catalyst.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for the harmless disposal and classified resource utilization of organosilicon slurry residue and waste catalyst, the method comprising the following steps: S1. The grinding hydrolysate from step S1, the heap leaching solution from step S3, and the organosilicon slurry slag premixed in the slurry slag premixing device are mixed in a concentrated acid hydrolysis kettle to carry out the hydrolysis reaction. After the hydrolysis reaction is completed, the solid and liquid are separated to obtain saturated acid hydrolysate and hydrolysis solid slag. Alternatively, the grinding hydrolysate from step S1, the heap leaching solution from step S3, and the organosilicon slurry and waste catalyst premixed in the slurry catalyst premixing device are mixed in a concentrated acid hydrolysis reactor to carry out a hydrolysis reaction. After the hydrolysis reaction is completed, solid-liquid separation is performed to obtain saturated acid hydrolysate and hydrolysis solid residue. Since the yield of waste catalyst is much lower than that of organosilicon slurry residue, and the interval between the generation of waste catalyst is relatively long, waste catalyst is only added sometimes and not sometimes; when it is not added, only the organosilicon slurry residue is premixed. S2. The hydrolyzed solid residue, together with the recovered siloxane washing wastewater and silicon powder washing wastewater from step S7, is ground and hydrolyzed in a grinding and hydrolysis device to obtain hydrolyzed residue powder and grinding and hydrolysis liquid. Part of the grinding hydrolysate is returned to the concentrated acid hydrolysis reactor in step S1 for hydrolysis reaction; The remaining grinding hydrolysate is transferred to step S3 and mixed with the remaining heap leachate; S3. Saturated acid hydrolysate and hydrolysate powder are leached together in a heap leaching tank to obtain heap leaching solution and heap leaching solid residue. Part of the heap leachate is returned to the concentrated acid hydrolysis reactor in step S1 for hydrolysis reaction; The remaining heap leaching solution and the remaining grinding hydrolysate from step S2 are mixed in a heap leaching solution collection tank, and an alkaline aqueous solution / alkaline solid residue is added to reduce the acidity to pH 1-2. After filtration to remove impurities, the solution is collected to obtain a copper-rich heap leaching solution. S4. The copper-rich heap leaching solution is transported to the sponge copper preparation unit, where it is reduced with iron powder to produce sponge copper (the obtained sponge copper meets the Cu-70 grade requirements of YS / T1366-2020 standard) and sponge copper production tail liquid. The tail liquid from the sponge copper production process is fed into a copper-deficient extraction and back-extraction unit to extract and back-extract copper elements, yielding a copper electrodeposition-rich solution and a copper extraction tail liquid. The copper electrodeposition solution enters the copper electrodeposition apparatus and undergoes copper electrodeposition to obtain metallic copper (the obtained metallic copper meets the requirements of standard copper No. 2 in GB / T 467-2010). S5. The copper extraction tail liquid is transported to the zinc extraction and back-extraction unit to extract and back-extract zinc elements, resulting in zinc electrodeposition rich solution and zinc extraction tail liquid. The zinc extraction tail liquid is transported via pipeline to a waste liquid treatment unit for neutralization. The zinc electrowinning solution is transported to the zinc electrowinning device, and after zinc electrowinning, metallic zinc is obtained (the obtained metallic zinc meets the second grade of GB / T6890-2012 standard). S6. After the heap leaching residue obtained in step S3 is dehydrated by pressing, it is mixed with organic solvent in a hydrolysis residue dissolving kettle to stir and dissolve the residue. Then, it is separated into liquid phase siloxane solution and solid phase recovered silicon powder in a solid-liquid separator. S7. After the solvent is recovered in the solvent recovery device, the recovered siloxane is transported to the siloxane washing tank and washed with water to obtain the cleaned recovered siloxane and the siloxane washing wastewater. The recycled siloxane washing wastewater is returned to the grinding and hydrolysis unit in step S2 for grinding and hydrolysis. The washed and recycled siloxane is mechanically transferred to the causticizing reactor for causticizing reaction to obtain sodium methylsilicate solution. The recycled silicon powder is added to the recycled silicon powder purification device, and after drying to remove the surface solvent under nitrogen protection, the dried recycled silicon powder is washed with water to obtain purified recycled silicon powder and silicon powder washing wastewater. The silicon powder washing wastewater is returned to the grinding and hydrolysis device in step S1 for grinding and hydrolysis; The purified recycled silicon powder is activated by boiling in water and then undergoes a causticizing reaction in a silicon powder reactor to obtain alkaline silica sol. Alkaline silica sol is prepared by adding water in a silica sol preparation device to obtain silica sol (the obtained silica sol meets the requirements of HG / T 2521-2008 standard for alkaline sodium type JN-20, JN-25, JN-30, and JN-40). Steps S4 and S7 are for illustrative purposes only and are not intended to limit the specific order. Alternatively, the method may include specific steps performed in the following order: step S1, step S2, step S3, step S6, step S7, step S4, and step S5. Alternatively, the method may include the following specific steps performed in sequence: after steps S1 to S3, steps S4 to S5 and steps S6 to S7 are performed simultaneously.

[0007] Furthermore, the method also includes the following steps: The zinc extraction tail liquid obtained in step S5 is bubbled with air at room temperature for 0.5 to 2 hours. During the bubbling process, a small amount of residual Fe is removed. 2+ All converted to Fe 3+ Then, the alkaline aqueous solution or alkaline solid residue from the soda ash industry is used together in the waste liquid treatment device to neutralize the zinc extraction tail liquid after bubbling treatment until the pH value reaches 7-8, forming a precipitate mainly composed of iron hydroxide and carbonate and a weakly alkaline wastewater mainly composed of magnesium chloride, calcium chloride and sodium chloride. The reason for using air bubbling to treat the zinc extraction tail liquid first is that the zinc extraction tail liquid contains a small amount of ferrous iron. To completely precipitate ferrous iron, a relatively high pH value (pH≥9.0) is required. However, the alkaline aqueous solution or alkaline solid residue in the soda ash industry is relatively weak and it is not easy to reach this pH value. After converting ferrous iron to ferric iron, the iron element can be precipitated at a pH value of 7~8, thereby reducing the iron content in the weakly alkaline aqueous solution and making it easier to use as brine in the soda ash industry. The alkaline aqueous solution or alkaline solid residue in this invention are both alkaline aqueous solutions or alkaline solid residues generated during the production process of the soda ash industry. The sediment is mechanically transported to the iron sludge drying yard, where it is dried to obtain iron sludge. The iron oxide content in the iron sludge is ≥60%. The impurities in the iron sludge are mainly CaSO4 from alkaline aqueous solution or alkaline solid slag (approximately 20%), insoluble matter from acid (approximately 10%), and Al(OH)3 from organosilicon slurry (approximately 10%). Weakly alkaline wastewater is treated with COD and then recycled to obtain brine for use in the soda ash industry.

[0008] Furthermore, in step S7, before adding water to alkaline silica sol to prepare silica sol, unreacted silica powder needs to be recovered in a silica powder recovery device. The unreacted silicon powder obtained from the recovery process, along with the purified recovered silicon powder obtained in the next round, is fed into a silicon powder reactor for water-boiling activation and causticizing reactions.

[0009] Furthermore, in step S1, during the hydrolysis reaction, a gas is formed, which mainly contains water vapor, hydrogen chloride and air. After the gas is purified by a suspension separator, the water content is reduced to less than 5% and purified gas (mainly recovered hydrogen chloride). The purified gas can be used for organosilicon production.

[0010] Furthermore, in step S1, the hydrolysis reaction ends when no obvious gas is produced; the hydrolysis reaction does not require temperature control and the hydrolysis reaction time is generally 10~120 min; In step S2, the volume of the grinding hydrolysate returned to step S1 for hydrolysis reaction is equal to that of the remaining heap leachate in step S3. In step S3, the heap leaching time is 8~24h and the temperature is 10~60℃; The heap leachate returned to step S1 for hydrolysis accounts for 70-85% of the total volume of the heap leachate produced in step S3. That is, the volume ratio of the grinding hydrolysate to the heap leachate in step S1 is 150~300:700~850; In step S5, before zinc electrowinning, the obtained zinc electrowinning rich solution needs to be treated with hydrogen peroxide and alkali neutralization process to remove trace iron elements (the hydrogen peroxide and alkali neutralization process is that iron elements are oxidized into ferric ions by hydrogen peroxide, and the ferric ions react with hydroxide ions contained in alkali to generate ferric hydroxide precipitate, which can be removed by filtration, thereby removing trace iron elements) and trace copper elements are removed by zinc metal replacement method. In step S6, the stirring and dissolving time is 30~120 min; In step S7, the recovered solvent obtained by using the siloxane solution is returned to the hydrolysis solid residue dissolving vessel in step S6 and reused as an organic solvent. In the water washing process for recovering siloxanes, the amount of water used is 50-200% of the weight of the recovered siloxanes. The obtained sodium methylsilicate product has a sodium methylsilicate solid content of ≥65wt% and a methylsilsesquioxane content of ≥40wt%. During the process of removing surface solvent from silicon powder, the removed surface solvent is recycled and returned to the hydrolysis solid residue dissolution kettle in step S6 as a recycled solvent for reuse as an organic solvent. During the washing process of the dried recycled silicon powder, the amount of water used is 50-200% of the weight of the dried recycled silicon powder.

[0011] Furthermore, in step S2, the particle size of the hydrolyzed residue powder after grinding and hydrolysis is less than 100 micrometers; In step S3, the volume-to-weight ratio of saturated acid hydrolysate to hydrolysate powder is 1000~2000L:800~900kg; The volume-to-weight ratio of the remaining heap leachate, the remaining grinding hydrolysate, and the alkaline aqueous solution / alkaline solid residue is 150~300L:1000~2000L:300~500kg; Among them, alkaline aqueous solution or alkaline solid residue are alkaline aqueous solution or alkaline solid residue generated during the production process of soda ash industry; After heap leaching, the copper leaching rate was over 99%. The concentration of copper ions in the copper-rich heap leaching solution is 6~30 g / L; In step S4, the concentration of copper ions in the tail liquid from the sponge copper production is 2~10 g / L; In the extraction and back-extraction process of copper, the extraction process uses an extractant solution, which is obtained by diluting the extractant with an extractant diluent. The extractant is at least one of dithiobis(2-ethylhexyl)phosphoric acid, pyridine carboxylate, and salicylaldehyde oxime; The extractant diluent is at least one of kerosene, solvent oil, aliphatic compounds, and aromatic compounds; The concentration of extractant in the extract solution is 5-10 vol%. The volume ratio of the extract to the tailings from the sponge copper preparation is 0.8~1.2:1; The back-extraction process involves contacting a copper-loaded extract with a copper-electrolyte-free electrolyte. The copper ions loaded in the extract then enter the electrolyte, where H+ ions are released. + The copper electrodeposition solution is exchanged into the extraction solution to obtain a copper-rich electrolyte. During the back-extraction process, the volume ratio of the copper-loaded extract to the lean electrolyte is 1~10:1; The copper electrodeposition solution used in the copper electrowinning process is a conventional configuration used in the copper hydrometallurgical process. The main components of the copper electrodeposition solution are a mixed solution of CuSO4 and H2SO4. The copper electrodeposition solution can be either a lean electrolyte or a rich electrolyte. The lean electrolyte contains 140~170 g / L of H2SO4 and 25~35 g / L of copper, while the rich electrolyte contains 40~50 g / L of copper. The concentration of copper ions in the copper extraction tail liquid is below 0.4 g / L; In step S5, during the extraction and back-extraction of zinc, a zinc extract solution is used for extraction; the zinc extract solution is obtained by diluting the zinc extractant with a zinc extractant diluent. The zinc extractant is at least one of tributyl phosphate, trihexyl (tetraalkyl) phosphine chloride, and monothiophosphonic acid; The zinc extractant diluent is at least one of kerosene, solvent oil, aliphatic compounds, and aromatic compounds; The zinc extractant concentration in the zinc extract solution is 5-10 vol%. The volume ratio of zinc extract to copper extract tail liquid is 0.8~1.2:10; The back-extraction process involves contacting a zinc extract loaded with zinc ions with a zinc-lean electrolyte obtained from zinc electrodeposition. The zinc ions loaded in the zinc extract then enter the zinc-lean electrolyte, where H+ ions are released. + The zinc is exchanged into the zinc extraction solution to obtain a zinc electrodeposition-rich solution; During the back-extraction process, the volume ratio of the zinc extract loaded with zinc ions to the zinc-poor electrolyte is 1~10:1; The zinc electrowinning solution used in the zinc electrowinning process is a conventional configuration used in the zinc hydrometallurgical process. The main components of the zinc electrowinning solution are a mixed solution of ZnSO4 and H2SO4. The zinc electrowinning solution is either a zinc-lean electrolyte or a zinc-rich electrolyte. The zinc-lean electrolyte contains 125~155 g / L of H2SO4 and 25~35 g / L of zinc, while the zinc-rich electrolyte contains 40~50 g / L of zinc. The concentration of zinc ions in the zinc extraction tail liquid is below 0.2 g / L; In step S6, the organic solvent is at least one of toluene, xylene, solvent oil, small molecule siloxane, heptane, and cycloheptane; In step S7, sodium hydroxide is added during the causticization reaction of the washed recycled siloxane; wherein the weight ratio of the washed recycled siloxane to sodium hydroxide is 3~5:2~3, the causticization reaction time is 0.5~2h, and the temperature is 60~100℃. During the water-boiling activation process, 1 to 2 times the weight of the purified recycled silicon powder needs to be added to the water; the water-boiling activation time is 0.5 to 2 hours and the temperature is 60 to 80℃. After the purified recycled silicon powder is activated by boiling in water, a causticizing reaction is carried out. Sodium hydroxide aqueous solution is also added. The weight ratio of the purified recycled silicon powder to the sodium hydroxide aqueous solution is 35~40:1. The causticizing reaction takes 5~10 hours and the temperature is 80~95℃.

[0012] Furthermore, in step S1, waste catalyst may be added during the hydrolysis reaction; The volume-to-weight ratio of the four components undergoing hydrolysis—grinding hydrolysate, heap leaching solution, organosilicon slurry residue, and waste catalyst—is 150~600L: 700~1700L: 800~1000kg: 0~200kg. In step S2, the weight-to-volume ratio of the hydrolysis solid residue, the recovered siloxane washing wastewater, and the silicon powder washing wastewater is 800~900kg: 200~800L: 350~1400L; In step S3, the volume-to-weight ratio between the saturated acid hydrolysate and the hydrolysate powder is 1000~2000L:800~900kg; In step S4, the volume-to-weight ratio of copper-rich heap leaching solution to iron powder is 500~2500L:13~30kg. In step S6, the weight-to-volume ratio of the dehydrated heap leaching residue to the organic solvent is 800~900kg:800~1800L; In step S7, depending on the required product, water is added to alkaline silica sol to prepare silica sol. The weight ratio of alkaline silica sol to water can be 1100~1300kg:500~2400kg.

[0013] A system for the harmless disposal and classified resource utilization of organosilicon slurry residue and waste catalyst, the system comprising a concentrated acid hydrolysis kettle, a grinding hydrolysis device, a heap leaching tank, a heap leaching liquor collection tank, a sponge copper preparation device, a copper extraction and back-extraction device, a copper electrowinning device, a zinc extraction and back-extraction device, a zinc electrowinning device, a hydrolysis solid residue dissolving kettle, a solid-liquid separator, a solvent recovery device, a siloxane causticizing kettle, a silicon powder purification device, a silicon powder reaction kettle, a silicon powder recovery device, a silica sol preparation device, and a waste liquid treatment device; The concentrated acid hydrolysis kettle, grinding and hydrolysis device, heap leaching tank, heap leaching liquid collection tank, sponge copper preparation device, copper extraction and back-extraction device, zinc extraction and back-extraction device and zinc electrowinning device are connected in sequence. The copper extraction and back-extraction device is also connected to the copper electrowinning device; The heap leaching tank is connected to the hydrolysis solid residue dissolution vessel and the concentrated acid hydrolysis vessel, respectively. The hydrolysis solid residue dissolving vessel is connected to the solid-liquid separator; The solid-liquid separator is connected to the solvent recovery unit and the silicon powder recovery and purification unit, respectively. The solvent recovery unit is connected to the siloxane recovery washing tank and the hydrolysis solid residue dissolution tank, respectively. The siloxane recovery washing kettle is connected to the siloxane recovery causticizing kettle and the grinding and hydrolysis device, respectively. The silicon powder recovery and purification device is connected to the silicon powder reaction vessel, the hydrolysis solid slag dissolution vessel, and the grinding and hydrolysis device, respectively. The silicon powder reactor is connected to the silicon powder recovery device; The silicon powder recycling device is connected to the silica sol preparation device.

[0014] Furthermore, the concentrated acid hydrolysis reactor is also connected to a slurry / residue catalyst premixing device; The concentrated acid hydrolysis vessel is also connected to a suspension separator; The silica sol preparation device is connected to the waste liquid treatment device; The waste liquid treatment unit is also connected to the zinc extraction and back-extraction unit and the iron sludge drying yard.

[0015] Furthermore, the heap leaching tank is equipped with a stirring device and a bubbling device; Multiple heap leaching tanks are set up, and the feeding and discharging of materials are alternated among the multiple heap leaching tanks.

[0016] The beneficial effects of the method and system for the harmless disposal and classified resource utilization of organosilicon slurry residue and waste catalyst of the present invention are as follows: The method and system of this invention, by classifying and processing the components of organosilicon slurry residue and waste catalyst to form and recover eight products, including hydrogen chloride gas, sponge copper, metallic copper, metallic zinc, sodium methylsilicate, silica sol, brine, and iron sludge, realizes the full-component resource utilization of organosilicon slurry residue and waste catalyst, and solves the problems of low resource utilization rate, large amount of secondary waste, and poor operation efficiency of existing organosilicon slurry residue and waste catalyst treatment processes in the industry. The method and system of this invention utilize the full-component resources of organosilicon slurry residue and waste catalyst, resulting in products with high added value. Furthermore, the method and system of this invention have strong profitability. The metal ions in the brine are almost entirely sodium ions, which can be used in the brine of the soda ash industry, achieving zero discharge of waste gas, wastewater, and solid waste. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the system for the harmless treatment and classified resource utilization of organosilicon slurry residue and waste catalyst in Embodiment 1 of the present invention; Figure 2 This is a process flow diagram of the harmless treatment and classified resource utilization of organosilicon slurry residue and waste catalyst in Embodiment 1 of the present invention. Detailed Implementation

[0018] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0019] Example 1: A method and system for the harmless disposal and classified resource utilization of organosilicon slurry residue and waste catalyst. I. A system for the harmless treatment and classified resource utilization of organosilicon slurry residue and waste catalysts. This embodiment describes a system for the harmless disposal and classified resource utilization of organosilicon slurry residue and waste catalysts. (See...) Figure 1 The system includes a slurry catalyst premixing device, a concentrated acid hydrolysis kettle, a grinding hydrolysis device, a heap leaching tank, a heap leaching liquor collection tank, a sponge copper preparation device, a copper extraction and back-extraction device, a copper electrowinning device, a zinc extraction and back-extraction device, a zinc electrowinning device, a hydrolysis solid slag dissolving kettle, a solid-liquid separator, a solvent recovery device, a siloxane causticizing kettle, a silicon powder purification device, a silicon powder reaction kettle, a silicon powder recovery device, a silica sol preparation device, a waste liquid treatment device, and an iron sludge drying yard. The following components are connected in sequence: slurry catalyst premixing device, concentrated acid hydrolysis kettle, grinding and hydrolysis device, heap leaching tank, heap leaching liquid collection tank, sponge copper preparation device, copper extraction and back-extraction device, zinc extraction and back-extraction device and zinc electrowinning device. The concentrated acid hydrolysis reactor is also connected to a suspension separator to purify the water vapor generated during the hydrolysis and acidification process. The concentrated acid hydrolysis reactor is connected to the heap leaching tank, typically via at least two pipes, one for transporting the saturated acid hydrolysate and the other for transporting the heap leaching solution. The pipe transporting the saturated acid hydrolysate must also pass through a device capable of solid-liquid separation (such as a centrifuge or filter). The separated liquid, the saturated acid hydrolysate, is transported through the pipes to the inlet of the heap leaching tank. The separated solid, the hydrolysis residue, is mechanically transferred to the grinding and hydrolysis unit.

[0020] The grinding and hydrolysis unit is connected via pipelines to the inlet of the heap leaching tank, the inlet of the concentrated acid hydrolysis reactor, the inlet of the heap leaching solution collection tank, the siloxane recovery washing tank, and the silicon powder recovery purification unit. Part of the grinding hydrolysate produced in the grinding and hydrolysis unit is returned to the concentrated acid hydrolysis reactor, while the remaining grinding hydrolysate enters the heap leaching tank collection tank and mixes with the heap leaching solution. The hydrolyzed residue powder produced in the grinding and hydrolysis unit is mechanically transported to the heap leaching tank for heap leaching.

[0021] Multiple heap leaching tanks are typically set up, with feeding and discharging occurring alternately between them. The pipes used to transport the heap leaching solution are directly connected at both ends to the outlets of the concentrated acid hydrolysis reactor and the heap leaching tanks. The heap leaching tanks are also equipped with stirring and bubbling devices. The outlets of the heap leaching tanks are also connected to a mechanical filtration device (such as a plate and frame filter press). This mechanical filtration device is connected to a heap leaching solution collection tank via pipe to filter out mechanical impurities before conveying the solution to the collection tank. In the collection tank, the heap leaching solution is mixed with the grinding hydrolysate and then connected to the sponge copper preparation device via pipe.

[0022] The heap leaching tank is also connected to the hydrolysis solid residue dissolving kettle via a dewatering device (which can be a pressing dewatering device). The heap leaching solid residue generated in the heap leaching tank is dewatered by pressing and then mechanically transported to the hydrolysis solid residue dissolving kettle.

[0023] The copper extraction and back-extraction unit is connected to the sponge copper preparation unit, the copper electrowinning unit, and the zinc extraction and back-extraction unit via pipelines. The tail liquid of sponge copper preparation obtained from the sponge copper preparation unit is transported to the copper extraction and back-extraction unit, the copper electrowinning rich liquid obtained from the copper extraction and back-extraction unit is transported to the copper electrowinning unit, and the copper extraction tail liquid obtained from the copper extraction and back-extraction unit is transported to the zinc extraction and back-extraction unit.

[0024] The zinc extraction and back-extraction unit is connected to the zinc electrowinning unit and the waste liquid treatment unit through pipelines, respectively. The zinc electrowinning rich solution obtained from the zinc extraction and back-extraction unit is transported to the zinc electrowinning unit, and the zinc extraction tail liquid obtained from the zinc extraction and back-extraction unit is transported to the waste liquid treatment unit for neutralization treatment.

[0025] The hydrolysis solid residue dissolving vessel is connected to a solid-liquid separator via a pipeline. The solid-liquid separator is also connected to a solvent recovery device via a pipeline, and is connected to a silicon powder recovery and purification device. The mixture obtained after stirring and dissolving the heap leaching solid residue with an organic solvent is transported to the solid-liquid separator for solid-liquid separation. The resulting liquid phase, a siloxane solution, is transported to the solvent recovery device via a pipeline, while the resulting solid phase, the recovered silicon powder, is mechanically transferred to the silicon powder recovery and purification device.

[0026] The solvent recovery unit is also connected to the siloxane washing tank and the hydrolysis solid residue dissolving tank via pipelines. The recovered siloxane is transported to the siloxane washing tank, and the recovered solvent is transported back to the hydrolysis solid residue dissolving tank for use as an organic solvent.

[0027] The siloxane recovery washing kettle is also connected to the siloxane recovery causticizing kettle and the grinding and hydrolysis device through a separation device (which can be a centrifuge or a filter). The washed siloxane is mechanically transferred to the siloxane causticizing kettle, and the siloxane washing wastewater is transported to the grinding and hydrolysis device through a pipeline.

[0028] The silicon powder recovery and purification device is also connected to the hydrolysis solid slag dissolution kettle, the silicon powder reaction kettle, and the grinding and hydrolysis device. The surface solvent removed by the silicon powder recovery and purification device is recovered and transported to the hydrolysis solid slag dissolution kettle for reuse as an organic solvent. The purified recovered silicon powder is mechanically transferred to the silicon powder reaction kettle for water boiling activation and causticization reaction. At the same time, the silicon powder washing wastewater is transported to the hydrolysis solid slag dissolution kettle through the pipeline.

[0029] The silicon powder reactor is also connected to a silicon powder recovery device, which transports the alkaline silica sol obtained from the silicon powder reactor to the silicon powder recovery device to recover unreacted silicon powder, and then transfers the recovered unreacted silicon powder back to the silicon powder reactor.

[0030] The silicon powder recovery device is also connected to the silica sol preparation device, which transports the alkaline silica sol after the unreacted silicon powder has been recovered to the silica sol preparation device to produce silica sol.

[0031] The silica sol preparation device is also connected to a waste liquid treatment device, which transports the waste alkaline liquid generated during the silica sol production process to the waste liquid treatment device for neutralizing the zinc extraction tail liquid transported from the zinc extraction and back-extraction device.

[0032] The waste liquid treatment unit is also connected to the iron sludge drying yard, which mechanically transports the precipitates generated during the neutralization reaction to the iron sludge drying yard for drying, and sends the neutral wastewater generated during the neutralization reaction for COD treatment.

[0033] II. A method for the harmless disposal and classified resource utilization of organosilicon slurry residue and waste catalysts. This embodiment describes a system for the harmless treatment and classified resource utilization of organosilicon slurry residue and waste catalysts. See [link to system]. Figure 1 and Figure 2 This includes the following steps: S1, hydrolysis of organosilicon slurry residue and waste catalyst The grinding hydrolysate from step S2, the heap leaching solution from step S3, and the organosilicon slurry and waste catalyst premixed in the slurry-catalyst premixing device are mixed in a concentrated acid hydrolysis reactor to carry out a hydrolysis reaction. The hydrolysis reaction ends when no obvious gas is produced. The hydrolysis reaction does not require temperature control and the hydrolysis reaction time is generally 10~120min. After the hydrolysis reaction is completed, solid-liquid separation is performed to obtain saturated acid hydrolysate and hydrolyzed solid residue. Alternatively, the grinding hydrolysate from step S2, the heap leaching solution from step S3, and the organosilicon slurry and waste catalyst premixed in the slurry-catalyst premixing device are mixed in a concentrated acid hydrolysis reactor to carry out a hydrolysis reaction. The hydrolysis reaction ends when no obvious gas is produced. The hydrolysis reaction does not require temperature control, and the hydrolysis reaction time is generally 10~120min (60min in this embodiment). After the hydrolysis reaction is completed, solid-liquid separation is performed to obtain saturated acid hydrolysate and hydrolyzed solid residue. Since the yield of waste catalyst is much lower than that of organosilicon slurry residue, and the interval between the generation of waste catalyst is relatively long, waste catalyst is only added sometimes and not sometimes; when it is not added, only the organosilicon slurry residue is premixed. The volume-to-weight ratio of the four components undergoing hydrolysis—grinding hydrolysate, heap leaching solution, organosilicon slurry residue, and waste catalyst—is 150-600L: 700-1700L: 800-1000kg: 0-200kg. In this embodiment, waste catalyst is added, and the volume-to-weight ratio of the four components undergoing hydrolysis—grinding hydrolysate, heap leaching solution, organosilicon slurry residue, and waste catalyst—is 200L: 800L: 950kg: 50kg. During the hydrolysis reaction, the gas formed mainly contains water vapor, hydrogen chloride and air. After the gas is purified by a suspension separator, the water content is reduced to less than 5% (mainly recovered hydrogen chloride, and in this embodiment the water content of the recovered hydrogen chloride is 5%). The purified gas can be used for organosilicon production.

[0034] S2, Grinding and hydrolysis of hydrolyzed solids The hydrolysis solid residue, together with the recovered siloxane washing wastewater and silicon powder washing wastewater from step S7, is ground and hydrolyzed in a grinding and hydrolysis device to obtain hydrolysis residue powder and grinding and hydrolysis liquid. The particle size of the hydrolysis residue powder after grinding and hydrolysis is less than 100 micrometers. The weight-to-volume ratio of hydrolysis solid slag, siloxane recovery washing wastewater, and silicon powder washing wastewater is 800-900 kg: 200-800 L: 350-1400 L; in this embodiment, the weight-to-volume ratio of hydrolysis solid slag, siloxane recovery washing wastewater, and silicon powder washing wastewater is 817 kg: 387 L: 791 L. Part of the grinding hydrolysate is returned to the concentrated acid hydrolysis reactor in step S1 for hydrolysis reaction; The remaining grinding hydrolysate is transferred to step S3 and mixed with the remaining heap leachate.

[0035] S3, mixed heap leaching of saturated acid hydrolysate The saturated acid hydrolysate and the hydrolysate powder are heap leached together in a heap leaching tank at a temperature of 10~60℃ for 8~24h (in this embodiment, the heap leaching temperature is 25℃ and the time is 12h). After the heap leaching is completed, the copper leaching rate is above 99% (in this embodiment, the copper leaching rate is 99.5%), and the heap leaching solution and heap leaching solid residue are obtained. The volume-to-weight ratio of saturated acid hydrolysate to hydrolysate powder is 1000-2000L:800-900kg; in this embodiment, the volume-to-weight ratio of saturated acid hydrolysate to hydrolysate powder is 1000L:817kg. 70-85% of the total volume of the heap leachate produced in step S3 is returned to the concentrated acid hydrolysis reactor in step S1 for hydrolysis reaction; in this embodiment, the heap leachate returned to step S1 for hydrolysis reaction accounts for 80% of the total volume of the heap leachate produced in step S3. In step S2, the volume of the grinding hydrolysate returned to step S1 for hydrolysis is equal to that of the remaining heap leachate in step S3; that is, in this embodiment, the grinding hydrolysate returned to step S1 for hydrolysis accounts for 20% of the total volume of the heap leachate generated in step S3; that is, the volume ratio of the grinding hydrolysate returned to step S1 for hydrolysis to the heap leachate is 200L:800L.

[0036] The remaining heap leaching solution is mechanically filtered to remove mechanical impurities. It is then mixed with the remaining grinding hydrolysate from step S2 in the heap leaching solution collection tank. An alkaline aqueous solution / alkaline solid residue is added to reduce the acidity to a pH of 1-2 (in this embodiment, the pH is adjusted to 1). After filtration to remove impurities, the solution is collected to obtain a copper-rich heap leaching solution. The concentration of copper ions in the copper-rich heap leaching solution is 6-30 g / L. In this embodiment, the concentration of copper ions in the copper-rich heap leaching solution is 8.1 g / L.

[0037] The volume-to-weight ratio of the remaining heap leaching solution, the remaining grinding hydrolysate, and the alkaline aqueous solution / alkaline solid residue is 150~300L:1000~2000L:300~500kg; in this embodiment, the volume-to-weight ratio of the remaining heap leaching solution, the remaining grinding hydrolysate, and the alkaline aqueous solution / alkaline solid residue is 200L:1500L:400kg. The alkaline aqueous solution or alkaline solid residue refers to the alkaline aqueous solution or alkaline solid residue generated during the production process of the soda ash industry.

[0038] S4. Hydrometallurgical copper processing using heap leaching solutions The copper-rich heap leaching solution is transported to the sponge copper preparation device, where it is reduced by iron powder to produce sponge copper (the obtained sponge copper meets the Cu-70 grade requirements of YS / T1366-2020 standard) and sponge copper preparation tail liquid. The concentration of copper ions in the sponge copper preparation tail liquid is reduced to 2~10 g / L (in this embodiment, the concentration of copper ions in the sponge copper preparation tail liquid is reduced to 2.7 g / L). The volume-to-weight ratio of copper-rich heap leaching solution to iron powder is 500~2500L:13~30kg; in this embodiment, the volume-to-weight ratio of copper-rich heap leaching solution to iron powder is 1178L:20kg. The tail liquid from the sponge copper production process is fed into a copper-deficient extraction and back-extraction unit to extract and back-extract copper elements, yielding a copper electrodeposition-rich solution and a copper extraction tail liquid. The concentration of copper ions in the copper extraction tail liquid is below 0.4 g / L. In this embodiment, the concentration of copper ions in the copper extraction tail liquid is 0.4 g / L. In the extraction and back-extraction process of copper, the extraction is carried out using an extractant solution. The extractant solution is obtained by diluting the extractant with an extractant diluent. The extractant is at least one of dithiodi(2-ethylhexyl)phosphoric acid, pyridine carboxylate, and salicylaldehyde oxime. In this embodiment, dithiodi(2-ethylhexyl)phosphoric acid is used as the extractant. The extractant diluent is at least one of kerosene, solvent oil, aliphatic compounds, and aromatic compounds. In this embodiment, toluene is used as the extractant diluent. The extractant concentration in the extractant solution is 5-10 vol%, and in this embodiment, the extractant concentration is 10 vol%. The volume ratio of the extractant solution to the copper sponge tail liquid during the extraction process is 0.8-1.2:1. In this embodiment, the volume ratio of the extractant solution to the copper sponge tail liquid is 1:1. The back-extraction process involves contacting a copper-loaded extract with a copper-electrolyte-free electrolyte. The copper ions loaded in the extract then enter the electrolyte, where H+ ions are released. + The copper ions are exchanged into the extract to obtain a copper-rich electrolyte; during the back-extraction process, the volume ratio of the copper-loaded extract to the lean electrolyte is 1~10:1; in this embodiment, the volume ratio of the copper-loaded extract to the lean electrolyte is 5:1. The copper electrodeposition solution used in the copper electrowinning process is a conventional configuration used in copper hydrometallurgical processes. The main components of the copper electrodeposition solution are a mixed solution of CuSO4 and H2SO4. The copper electrodeposition solution can be either a lean electrolyte or a rich electrolyte. The lean electrolyte contains 140-170 g / L of H2SO4 and 25-35 g / L of copper, while the rich electrolyte contains 40-50 g / L of copper. In this embodiment, the lean electrolyte for copper electrowinning contains 150 g / L of H2SO4 and 30 g / L of copper, while the rich electrolyte contains 45 g / L of copper. The copper electrodeposition solution enters the copper electrodeposition apparatus and undergoes copper electrodeposition to obtain metallic copper (the obtained metallic copper meets the requirements of standard copper No. 2 in GB / T 467-2010).

[0039] S5, Hydrometallurgical zinc processing using copper extraction tailings The copper extraction tail liquid is fed into the zinc extraction and back-extraction device to extract and back-extract zinc elements, yielding zinc electrowinning solution and zinc extraction tail liquid; wherein, the concentration of zinc ions in the zinc extraction tail liquid is below 0.2 g / L, and in this embodiment, the concentration of zinc ions in the zinc extraction tail liquid is 0.2 g / L. In the extraction and back-extraction process of zinc, the extraction process uses a zinc extractant solution. The zinc extractant solution is obtained by diluting the zinc extractant with a zinc extractant diluent. The zinc extractant is at least one of tributyl phosphate, trihexyl (tetraalkyl)phosphine chloride, and monothiophosphonic acid. In this embodiment, tributyl phosphate is used as the zinc extractant. The zinc extractant diluent is at least one of kerosene, solvent oil, aliphatic compounds, and aromatic compounds. In this embodiment, toluene is used as the zinc extractant diluent. The concentration of the zinc extractant in the zinc extractant solution is 5-10 vol%. In this embodiment, the concentration of the zinc extractant in the zinc extractant solution is 10 vol%. The volume ratio of the zinc extractant solution to the copper extract tail liquid during the extraction process is 0.8-1.2:10. In this embodiment, the volume ratio of the zinc extractant solution to the copper extract tail liquid is 1:10. The back-extraction process involves contacting a zinc extract loaded with zinc ions with a zinc-lean electrolyte obtained from zinc electrodeposition. The zinc ions loaded in the zinc extract then enter the zinc-lean electrolyte, where H+ ions are released. + The zinc is exchanged into the zinc extract to obtain a zinc electrodeposition rich solution; during the back-extraction process, the volume ratio of zinc extract to zinc electrodeposition lean electrolyte is 1~10:1; in this embodiment, the volume ratio of zinc extract to zinc electrodeposition lean electrolyte is 5:1. The zinc electrodeposition solution used in the zinc electrowinning process is a conventional configuration used in the zinc hydrometallurgical process. The main components of the zinc electrodeposition solution are a mixed solution of ZnSO4 and H2SO4. The zinc electrodeposition solution can be either a zinc-lean electrolyte or a zinc-rich electrolyte. In the zinc-lean electrolyte, the H2SO4 content is 125-155 g / L and the zinc content is 25-35 g / L; in the zinc-rich electrolyte, the zinc content is 40-50 g / L. In this embodiment, the zinc-lean electrolyte has an H2SO4 content of 130 g / L and a zinc content of 30 g / L, while the zinc-rich electrolyte contains 45 g / L of zinc. The zinc extraction tail liquid generated in step S5 is transported through a pipeline to a waste liquid treatment device for neutralization treatment. The zinc electrowinning solution uses a hydrogen peroxide and alkali neutralization process to remove trace iron (the hydrogen peroxide and alkali neutralization process involves oxidizing iron to ferric ions with hydrogen peroxide, which then react with hydroxide ions in the alkali to form ferric hydroxide precipitate, which is then removed by filtration, thus removing trace iron) and a zinc displacement method to remove trace copper. After this process, the solution is transported to the zinc electrowinning device for zinc electrowinning to obtain metallic zinc (the obtained metallic zinc meets the second grade of GB / T 6890-2012 standard).

[0040] S6. Dissolution and separation of solid residue from heap leaching After the heap leaching solid residue obtained in step S3 is dehydrated by pressing, it is mixed with organic solvent in a hydrolysis solid residue dissolving kettle and stirred and dissolved for 30-120 minutes (in this embodiment, the stirring and dissolving time is 60 minutes). Then, it is separated in a solid-liquid separator to obtain a liquid phase siloxane solution and a solid phase recovered silicon powder. The organic solvent is at least one of toluene, xylene, solvent oil, small molecule siloxane, heptane, and cycloheptane; in this embodiment, the organic solvent is solvent oil. The weight-to-volume ratio of the dehydrated heap leaching solid residue to the organic solvent is 800-900 kg: 800-1800 L; in this embodiment, the weight-to-volume ratio of the dehydrated heap leaching solid residue to the organic solvent is 762 kg: 800 L.

[0041] S7, siloxane and silicon powder recycling S71. Recycling siloxanes to produce sodium methylsilicate products After the siloxane solution is solvent recovered in the solvent recovery device, the recovered siloxane is transported to the siloxane washing tank and then water is added at 50-200% of the weight of the recovered siloxane for washing (in this embodiment, the amount of water used is 100% of the weight of the recovered siloxane, that is, the amount of water used is equal to the weight of the recovered siloxane), resulting in cleaned recovered siloxane and siloxane washing wastewater. The recovered solvent obtained from the siloxane solution is returned to the hydrolysis solid residue dissolution vessel in step S6 and reused as an organic solvent. The recycled siloxane washing wastewater is returned to the grinding and hydrolysis unit in step S2 for grinding and hydrolysis. The cleaned recycled siloxane is mechanically transferred to a causticizing reactor for siloxane recycling. Sodium hydroxide and an appropriate amount of water are added, and the causticizing reaction is carried out at a temperature of 60~100℃ for 0.5~2h (in this example, the causticizing reaction temperature is 70℃ and the time is 1h) to obtain a sodium methylsilicate solution (sodium methylsilicate content ≥65wt%, methylsilsesquioxane content ≥40wt%, in this example, the sodium methylsilicate content is 65% and the methylsilsesquioxane content is 42%). The weight ratio of the washed recovered siloxane to sodium hydroxide is 3~5:2~3. In this embodiment, the weight ratio of the washed recovered siloxane to sodium hydroxide is 387kg:220kg.

[0042] S72, Preparation of silica sol from recycled silicon powder The recycled silicon powder is added to the recycled silicon powder purification device and dried under nitrogen protection to remove the surface solvent. The dried recycled silicon powder is then washed with water at 50-200% of its weight (in this embodiment, the amount of water used is 100% of the weight of the dried recycled silicon powder, that is, the amount of water used is equal to the weight of the dried recycled silicon powder) to obtain purified recycled silicon powder and silicon powder washing wastewater. During the process of removing surface solvent from silicon powder, the removed surface solvent is recycled and returned to the hydrolysis solid residue dissolution kettle in step S6 as a recycled solvent for reuse as an organic solvent. The silicon powder washing wastewater is returned to the grinding and hydrolysis device in step S1 for grinding and hydrolysis; The purified recycled silicon powder is placed in a silicon powder reactor, and water with a weight of 1 to 2 times that of the purified recycled silicon powder is added (in this embodiment, water with a weight of 1 times that of the purified recycled silicon powder is added). The reactor is then activated by boiling in water at a temperature of 60 to 80°C for 0.5 to 2 hours (in this embodiment, the temperature of the boiling activation is 70°C and the time is 1 hour). Then, an aqueous solution of sodium hydroxide is added, and a causticizing reaction is carried out at a temperature of 90°C for 6 hours (in this embodiment, the temperature of the causticizing reaction is 80 to 95°C and the time is 5 to 10 hours) to obtain alkaline silica sol. The weight ratio of the purified recycled silicon powder to the sodium hydroxide in the sodium hydroxide aqueous solution is 35~40:1; in this embodiment, the weight ratio of the purified recycled silicon powder to the sodium hydroxide in the sodium hydroxide aqueous solution is 375kg:10kg. The alkaline silica sol is transferred to a silicon powder recovery device to recover unreacted silicon powder. The recovered unreacted silicon powder, along with the purified recovered silicon powder obtained in the next round, is then fed into a silicon powder reactor for water boiling activation and causticization reactions.

[0043] After recovering the unreacted silica powder, the alkaline silica sol is transferred to a silica sol preparation device. Depending on the desired product, water is added to prepare silica sol (the obtained silica sol meets the requirements of HG / T 2521-2008 standard for alkaline sodium type JN-20, JN-25, JN-30, and JN-40). In this embodiment, the product specification obtained is JN-30.

[0044] The weight ratio of alkaline silica sol to water can be 1100~1300kg:500~2400kg. In this embodiment, according to product specification JN-30, the weight ratio of alkaline silica sol to water when preparing silica sol is 1347kg:1199kg.

[0045] It should be noted that steps S71 and S72 are not sequential. This embodiment is only for clarity. Step S71 is performed first to recover siloxane to prepare sodium methylsilicate, and then step S72 is performed to recover silicon powder to prepare silica sol. Alternatively, step S72 can be performed first to recover silicon powder to prepare silica sol, and then step S71 can be performed to recover siloxane to prepare sodium methylsilicate. Alternatively, step S71 to recover siloxane to prepare sodium methylsilicate and step S72 to recover silicon powder to prepare silica sol can be performed simultaneously.

[0046] Furthermore, steps S4 and S7 are not necessarily sequential. The wet copper smelting in step S4 (heap leaching) can be performed first, followed by the recovery of siloxane and silicon powder in step S7; alternatively, the recovery of siloxane and silicon powder in step S7 can be performed first, followed by the wet copper smelting in step S4; or the wet copper smelting in step S4 and the recovery of siloxane and silicon powder in step S7 can be performed simultaneously. That is, the method further includes specific steps performed in the following order: steps S1, S2, S3, S6, S7, S4, and S5; or steps S4-S5 and steps S6-S7 can be performed simultaneously after steps S1 to S3.

[0047] S8. Preparation of Iron Sludge The zinc extraction tail liquid obtained in step S5 is bubbled with air at room temperature for 0.5~2 hours (1 hour in this example). During the bubbling process, a small amount of residual Fe is removed. 2+ All converted to Fe 3+ Then, the alkaline aqueous solution or alkaline solid residue from the soda ash industry is used together in the waste liquid treatment device to neutralize the zinc extraction tail liquid after bubbling treatment until the pH value reaches 7-8, forming a precipitate mainly composed of iron hydroxide and carbonate and a weakly alkaline wastewater mainly composed of magnesium chloride, calcium chloride and sodium chloride. The reason for using air bubbling to treat the zinc extraction tail liquid first is that the zinc extraction tail liquid contains a small amount of ferrous iron. To completely precipitate ferrous iron, a relatively high pH value (pH≥9.0) is required. However, the alkaline aqueous solution or alkaline solid residue in the soda ash industry is relatively weak and it is not easy to reach this pH value. After converting ferrous iron to ferric iron, the iron element can be precipitated at a pH value of 7~8, thereby reducing the iron content in the weakly alkaline aqueous solution and making it easier to use as brine in the soda ash industry. In this embodiment, the alkaline aqueous solution or alkaline solid residue is an alkaline aqueous solution or alkaline solid residue generated during the production process of the soda ash industry. The precipitate was mechanically transported to the iron sludge drying yard. After drying, iron sludge was obtained. The iron sludge contained ≥60% iron oxide. The impurities in the iron sludge mainly consisted of approximately 20% CaSO4 from alkaline aqueous solution or alkaline solid slag, approximately 10% insoluble matter from acid, and approximately 10% Al(OH)3 from organosilicon slurry slag. In this example, the iron oxide content in the iron sludge was 64.2%. Weakly alkaline wastewater is treated with COD and then recycled to obtain brine for use in the soda ash industry.

[0048] Examples 2-5: Methods for the harmless treatment and classified resource utilization of organosilicon slurry residue and waste catalysts. Examples 2-5 are methods for the harmless treatment and classified resource utilization of organosilicon slurry residue and waste catalyst. Their steps are basically the same as the method for the harmless treatment and classified resource utilization of organosilicon slurry residue and waste catalyst in Example 1, the only differences being the raw material dosage and process parameters. See Table 1 for details. Table 1. Summary of process parameters in Examples 2-5 , , ,

[0049] The contents of other parts of Examples 2 to 5 are the same as those of Example 1, and will not be repeated here.

[0050] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A method for the harmless disposal and classified resource utilization of organosilicon slurry residue, characterized in that, The method includes the following steps: S1. The grinding hydrolysate from step S2, the heap leaching solution from step S3, and the organosilicon slurry are mixed and subjected to a hydrolysis reaction. After the hydrolysis reaction is completed, solid-liquid separation is performed to obtain a saturated acid hydrolysate and a hydrolysis solid residue. S2. The hydrolyzed solid residue is ground and hydrolyzed together with the recycled siloxane washing wastewater and silicon powder washing wastewater from step S7 to obtain hydrolyzed residue powder and grinding hydrolysate. Part of the grinding hydrolysate is returned to step S1 for hydrolysis reaction; The remaining grinding hydrolysate is transferred to step S3 and mixed with the remaining heap leachate; S3. The saturated acid hydrolysate and the hydrolysate powder are subjected to heap leaching together to obtain heap leaching solution and heap leaching solid residue. A portion of the heap leachate is returned to step S1 for hydrolysis. The remaining heap leaching solution is mixed with the remaining grinding hydrolysate from step S2, and an alkaline aqueous solution / alkaline solid residue is added to reduce the acidity. After filtration to remove impurities and collection, a copper-rich heap leaching solution is obtained. S4. The copper-rich heap leaching solution is reduced with iron powder to obtain sponge copper and the tailings of sponge copper production. The copper element is extracted and back-extracted from the tail liquid of sponge copper production to obtain copper electrodeposition rich solution and copper extraction tail liquid. Copper electrodeposition solution rich in copper is used for copper electrodeposition to obtain metallic copper; S5. The copper extraction tail liquid is used to extract and back-extract zinc to obtain zinc electrowinning rich solution and zinc extraction tail liquid. Zinc electrowinning solution is used for zinc electrowinning to obtain metallic zinc; S6. The heap leaching residue obtained in step S3 is dehydrated, mixed with an organic solvent to dissolve the residue, and then separated into a liquid phase of siloxane solution and a solid phase of recovered silicon powder. S7. After solvent recovery, the recovered siloxane solution is washed with water to obtain cleaned recovered siloxane and siloxane washing wastewater. The recycled siloxane washing wastewater is returned to step S2 for grinding and hydrolysis. The washed and recycled siloxanes are subjected to a causticization reaction to obtain a sodium methylsilicate solution. After removing the surface solvent from the recycled silicon powder, the dried recycled silicon powder is washed with water to obtain purified recycled silicon powder and silicon powder washing wastewater. The silicon powder washing wastewater is returned to step S2 for grinding and hydrolysis. The purified recycled silicon powder is activated by boiling in water and then subjected to a causticizing reaction to obtain alkaline silica sol. Silica sol is prepared by adding water to alkaline silica sol; Alternatively, the method may include the following specific steps performed in the following order: step S1, step S2, step S3, step S6, step S7, step S4, and step S5. Alternatively, the method may include the following specific steps performed in sequence: after steps S1 to S3, steps S4 to S5 and steps S6 to S7 are performed simultaneously.

2. The method for harmless disposal and classified resource utilization of organosilicon slurry residue according to claim 1, characterized in that, The method further includes the following steps: The zinc extraction tail liquid obtained in step S5 is bubbled with air for 0.5 to 2 hours. During the air bubbling process, a small amount of residual Fe is removed. 2+ All converted to Fe 3+ Then add alkaline aqueous solution or alkaline solid residue to neutralize to a pH of 7-8, forming precipitate and weakly alkaline wastewater; After drying, the precipitate yields iron mud; Weakly alkaline wastewater is treated with COD and then recycled to obtain brine for use in the soda ash industry.

3. The method for harmless disposal and classified resource utilization of organosilicon slurry residue according to claim 1 or 2, characterized in that, In step S7, before adding water to alkaline silica sol to prepare silica sol, unreacted silica powder needs to be recovered. The unreacted silicon powder obtained from the recovery process is combined with the purified recovered silicon powder and subjected to water boiling activation and causticization reactions.

4. The method for harmless disposal and classified resource utilization of organosilicon slurry residue according to claim 1 or 2, characterized in that, In step S1, during the hydrolysis reaction, a gas is formed. After the gas is purified by a suspension separator, the water content is reduced to less than 5%. The purified gas can be used for organosilicon production.

5. The method for harmless disposal and classified resource utilization of organosilicon slurry residue according to claim 1 or 2, characterized in that, In step S1, the hydrolysis reaction ends when no obvious gas is produced. In step S2, the volume of the grinding hydrolysate returned to step S1 for hydrolysis reaction is equal to that of the remaining heap leachate in step S3. In step S3, the heap leaching time is 8~24h and the temperature is 10~60℃; The heap leachate returned to step S1 for hydrolysis accounts for 70-85% of the total volume of the heap leachate produced in step S3. In step S5, before zinc electrowinning, the obtained zinc electrowinning solution needs to be treated with hydrogen peroxide and alkali neutralization to remove trace iron and zinc replacement to remove trace copper. In step S6, the dissolution time is 30~120 min; In step S7, the recovered solvent obtained by using the siloxane solution is returned to step S6 for reuse as an organic solvent. In the water washing process for recovering siloxanes, the amount of water used is 50-200% of the weight of the recovered siloxanes. The obtained sodium methylsilicate solution product has a sodium methylsilicate solid content ≥65wt% and a methylsilsesquioxane content ≥40wt%. During the process of removing surface solvent from silicon powder, the removed surface solvent is recycled and returned to step S6 as a recycled solvent for reuse as an organic solvent. During the washing process of the dried recycled silicon powder, the amount of water used is 50-200% of the weight of the dried recycled silicon powder.

6. The method for harmless disposal and classified resource utilization of organosilicon slurry residue according to claim 1 or 2, characterized in that, In step S2, the particle size of the hydrolyzed residue powder after grinding and hydrolysis is less than 100 micrometers; During step S3 heap leaching, the volume-to-weight ratio of saturated acid hydrolysate to hydrolysate powder is 1000~2000L:700~900kg; The volume-to-weight ratio of the remaining heap leachate, the remaining grinding hydrolysate, and the alkaline aqueous solution / alkaline solid residue is 150~300L:1000~2000L:300~500kg; After heap leaching, the copper leaching rate was over 99%. In step S4, during the extraction and back-extraction of copper, an extractant is used for extraction; the extractant is obtained by diluting the extractant with an extractant diluent. The extractant is at least one of dithiobis(2-ethylhexyl)phosphoric acid, pyridine carboxylate, and salicylaldehyde oxime; The extractant diluent is at least one of kerosene, solvent oil, aliphatic compounds, and aromatic compounds; The concentration of the extractant in the extract solution is 5-10 vol%. The volume ratio of the extract to the tailings from the sponge copper preparation is 0.8~1.2:1; The back-extraction process involves contacting a copper-loaded extract with a copper-electrolyte-free electrolyte. The copper ions loaded in the extract then enter the electrolyte, where H+ ions are released. + The copper electrodeposition solution is exchanged into the extraction solution to obtain a copper-rich electrolyte. During the back-extraction process, the volume ratio of the copper-loaded extract to the lean electrolyte is 1~10:1; The concentration of copper ions in the copper extraction tail liquid is below 0.4 g / L; In step S5, during the extraction and back-extraction of zinc, a zinc extract solution is used for extraction; the zinc extract solution is obtained by diluting the zinc extractant with a zinc extractant diluent. The zinc extractant is tributyl phosphate and / or monothiophosphonic acid; The zinc extractant diluent is at least one of kerosene, solvent oil, aliphatic compounds, and aromatic compounds; The concentration of zinc extractant in the zinc extraction solution is 5-10 vol%. The volume ratio of zinc extract to copper extract tail liquid is 0.8~1.2:10; The back-extraction process involves contacting a zinc extract loaded with zinc ions with a zinc-lean electrolyte obtained from zinc electrodeposition. The zinc ions loaded in the zinc extract then enter the zinc-lean electrolyte, where H+ ions are released. + The zinc is exchanged into the zinc extraction solution to obtain a zinc electrodeposition-rich solution; During the back-extraction process, the volume ratio of the zinc extract loaded with zinc ions to the zinc-poor electrolyte is 1~10:1; The concentration of zinc ions in the zinc extraction tail liquid is below 0.2 g / L; In step S6, the organic solvent is at least one of toluene, xylene, solvent oil, small molecule siloxane, heptane, and cycloheptane; In step S7, sodium hydroxide is added during the causticization reaction of the washed recycled siloxane; wherein the weight ratio of the washed recycled siloxane to sodium hydroxide is 3~5:2~3, the causticization reaction time is 0.5~2h, and the temperature is 60~100℃. During the water-boiling activation process, 1 to 2 times the weight of the purified recycled silicon powder needs to be added to the water; the water-boiling activation time is 0.5 to 2 hours and the temperature is 60 to 80℃. After the purified recycled silicon powder is activated by boiling in water, a causticizing reaction is carried out. A sodium hydroxide aqueous solution is also added. The weight ratio of the purified recycled silicon powder to the sodium hydroxide aqueous solution is 35~40:

1. The causticizing reaction takes 5~10 hours and the temperature is 80~95℃.

7. The method for harmless disposal and classified resource utilization of organosilicon slurry residue according to claim 1 or 2, characterized in that, In step S1, waste catalyst is also added during the hydrolysis reaction; The volume-to-weight ratio of the four components undergoing hydrolysis—grinding hydrolysate, heap leaching solution, organosilicon slurry residue, and waste catalyst—is 150~600L: 700~1700L: 800~1000kg: 0~200kg. In step S2, the weight-to-volume ratio of the hydrolysis solid residue, the recovered siloxane washing wastewater, and the silicon powder washing wastewater is 800~900kg: 200~800L: 350~1400L; In step S3, the volume-to-weight ratio of saturated acid hydrolysate to hydrolysate powder is 1000~2000L:800~900kg; In step S6, the weight-to-volume ratio of the dehydrated heap leaching solid residue to the organic solvent is 800~900kg:800~1800L.

8. A system for the harmless disposal and classified resource utilization of organosilicon slurry residue, characterized in that, The system is used to perform the method for harmless disposal and classified resource utilization of organosilicon slurry residue as described in any one of claims 1-7; The system includes a concentrated acid hydrolysis kettle, a grinding and hydrolysis device, a heap leaching tank, a heap leaching liquor collection tank, a sponge copper preparation device, a copper extraction and back-extraction device, a copper electrowinning device, a zinc extraction and back-extraction device, a zinc electrowinning device, a hydrolysis solid residue dissolution kettle, a solid-liquid separator, a solvent recovery device, a siloxane causticizing kettle, a silicon powder purification device, a silicon powder reaction kettle, a silicon powder recovery device, a silica sol preparation device, and a waste liquid treatment device. The concentrated acid hydrolysis kettle, grinding and hydrolysis device, heap leaching tank, heap leaching liquid collection tank, sponge copper preparation device, copper extraction and back-extraction device, zinc extraction and back-extraction device and zinc electrowinning device are connected in sequence. The copper extraction and back-extraction device is also connected to the copper electrowinning device; The heap leaching tank is connected to the hydrolysis solid residue dissolution vessel and the concentrated acid hydrolysis vessel, respectively. The hydrolysis solid residue dissolving vessel is connected to the solid-liquid separator; The solid-liquid separator is connected to the solvent recovery unit and the silicon powder recovery and purification unit, respectively. The solvent recovery unit is connected to the siloxane recovery washing tank and the hydrolysis solid residue dissolution tank, respectively. The siloxane recovery washing kettle is connected to the siloxane recovery causticizing kettle and the grinding and hydrolysis device, respectively. The silicon powder recovery and purification device is connected to the silicon powder reaction vessel, the hydrolysis solid slag dissolution vessel, and the grinding and hydrolysis device, respectively. The silicon powder reactor is connected to the silicon powder recovery device; The silicon powder recycling device is connected to the silica sol preparation device.

9. The system for the harmless disposal and classified resource utilization of organosilicon slurry residue according to claim 8, characterized in that, The concentrated acid hydrolysis reactor is also connected to the slurry and residue catalyst premixing device; The concentrated acid hydrolysis vessel is also connected to a suspension separator; The silica sol preparation device is connected to the waste liquid treatment device; The waste liquid treatment unit is also connected to the zinc extraction and back-extraction unit.

10. The system for the harmless disposal and classified resource utilization of organosilicon slurry residue according to claim 8 or 9, characterized in that, The heap leaching tank is equipped with a stirring device and a bubbling device; Multiple heap leaching tanks are set up, and the feeding and discharging of materials are alternated among the multiple heap leaching tanks.

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