Method and system for recovery of uranium from high-silica / high-phosphorus radioactively dissolved slags

Abstract

This invention belongs to the field of uranium recovery technology and discloses a method for uranium recovery from high-silicon / high-phosphorus radioactive dissolution slag. The invention uses multiphysics simulation software such as COMSOL to simulate the temperature distribution, thermal stress evolution, and sound field distribution of different phases in an ultrasonic-microwave synergistic field. Combined with measured data of dielectric and acoustic properties, the synergistic mechanism of microcrack nucleation and propagation and cavitation stripping is revealed. The disintegration behavior of the encapsulated matrix is ​​experimentally verified using SEM, XRD, and XPS. Based on this, an experiment is designed using the response surface methodology to systematically investigate the effects of key factors such as microwave power, ultrasonic power, synergistic mode, temperature, acid concentration, and liquid-to-solid ratio on the uranium leaching rate. The process parameters are globally optimized using artificial neural networks and genetic algorithms to obtain the optimal parameter combination for a uranium leaching rate ≥90%. The physicochemical properties of the leaching residue are systematically characterized, providing accurate raw material data for subsequent solidification research.

Description

Technical Field

[0001] This invention belongs to the field of uranium recovery technology, and particularly relates to a method and system for uranium recovery from high-silicon / high-phosphorus radioactive dissolution residue. Background Technology

[0002] High-silicon / high-phosphorus radioactive dissolution residue (RDR) is radioactive waste generated during uranium purification and conversion. Uranium in RDR is tightly encapsulated by stable silicon / phosphorus phases, making recovery difficult; moreover, the residue after secondary leaching still requires safe disposal, and a single technology cannot simultaneously address both resource recovery and environmental safety.

[0003] At the forefront of the nuclear fuel cycle, uranium ore is typically extracted using hydrometallurgical processes to obtain yellowcake (uranate). During subsequent purification and conversion, a large amount of complex radioactive dissolution residue (RDR) is inevitably generated. This secondary waste typically still contains a certain amount of uranium and various associated nuclides. Its characteristics include: due to its highly complex mineralogical composition, it exhibits high silicon, high phosphorus, and the coexistence of various heavy metal oxides; uranium often exists in the form of being encapsulated or dissolved in stable inert phases (such as silicates and phosphates). Currently, large quantities of RDR can only be temporarily stored indoors as radioactive solid waste. With the continued expansion of nuclear industry activities, RDR stockpiles are rapidly increasing, putting pressure on existing storage capacity. Furthermore, the potential leaching and migration risks of uranium and associated nuclides under long-term service conditions also pose ongoing environmental and safety hazards. Therefore, developing effective RDR disposal methods is of crucial research significance for environmental protection and the sustainable development of the nuclear industry.

[0004] Currently, research on the treatment of radioactive dissolution residues (RDRs) mainly follows two technical paths: resource recovery, which involves extracting residual uranium through secondary leaching; and safe disposal, which involves converting the RDRs into a stable form suitable for final disposal through solidification / stabilization techniques. Regarding resource recovery, secondary leaching research aims to maximize the recovery of uranium from RDRs to achieve waste reduction and resource recycling. However, due to the complex composition and irregular morphology of RDRs, and the fact that uranium is mostly distributed in a stable high-silicon / high-phosphorus inert phase within encapsulated structures, their leachingability is significantly reduced. Even with optimized processes, secondary leaching still produces a large amount of leaching residue primarily composed of silicon and phosphorus, containing residual radionuclides. This type of residue is stable and difficult to further leach, but its long-term safe disposal remains unresolved; relying solely on leaching cannot achieve closed-loop treatment of RDRs.

[0005] Given the limitations of secondary leaching in completely dissociating encapsulated uranium, and the essential requirement for the final safe disposal of leaching residues, combining secondary leaching recovery with subsequent solidification treatment to form an integrated technology route of resource recovery and stabilization disposal has become a more realistic and forward-looking strategy. This strategy first achieves uranium resource recovery and radioactivity reduction through secondary leaching, and then develops efficient solidification technologies for leaching residues rich in high silicon and phosphorus, fixing them in a chemically stable solidification matrix (such as glass-ceramics). This not only inherits the advantages of solidification treatment in long-term inhibition of nuclide migration and meeting the requirements of deep geological disposal, but also improves the overall resource efficiency and economics of the technology through a pre-emptive uranium recovery step. In the future, if technological advancements allow for the efficient recovery of nuclides from solidified bodies, these landfills may even become potential secondary resources, further supporting the sustainable development of nuclear energy. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a method and system for uranium recovery from high-silicon / high-phosphorus radioactive dissolution slag.

[0007] This invention is implemented as follows: a method for uranium recovery from high-silicon / high-phosphorus radioactive dissolution slag, comprising:

[0008] Step 1, RDR mineralogical characteristics and uranium occurrence state characterization;

[0009] Specifically, the process includes: First, drying, crushing, grinding, and sieving the high-silicon / high-phosphorus radioactive dissolution slag to obtain a sample with a relatively uniform particle size distribution. Then, X-ray fluorescence spectroscopy or inductively coupled plasma atomic emission spectrometry is used to determine the overall chemical composition of Si, P, Al, Ca, Fe, U, and other associated elements in the RDR, clarifying its high-silicon, high-phosphorus, and uranium-containing characteristics. X-ray diffraction is used to analyze the main crystalline phase composition in the RDR, identifying silicates, phosphates, oxides, and other stable inert mineral phases. Scanning electron microscopy combined with energy dispersive spectroscopy is used to observe the microstructure, particle aggregation state, and elemental distribution characteristics of the RDR particles. If necessary, electron probe microanalysis or micro-area Raman spectroscopy is used to further determine the spatial co-distribution relationship between uranium and elements such as silicon, phosphorus, calcium, and iron.

[0010] By using stepwise chemical extraction combined with ICP-MS or ICP-OES analysis, the proportions of exchangeable, carbonate-bound, iron-manganese oxide-bound, organic matter-bound, and residual states of uranium in the RDR were distinguished, and the proportion of refractory uranium encapsulated by stable silicates or phosphates was determined. Based on the above test results, the correspondence between phase composition, uranium occurrence morphology, uranium spatial distribution, and leaching difficulty in the RDR was established, providing a basis for the subsequent design of ultrasonic-microwave synergistic enhanced leaching parameters.

[0011] Meanwhile, a vector network analyzer was used to determine the dielectric constant, dielectric loss factor, and dielectric loss tangent of the RDR and its main mineral components at microwave frequencies to evaluate the absorption capacity of different minerals relative to microwave energy. Acoustic testing methods were used to obtain the acoustic propagation, acoustic attenuation, or cavitation response characteristics of the RDR slurry or particle system, providing a basis for the selection of ultrasonic action parameters. Based on this, the components in the RDR suitable for thermal stress cracking induced by microwave selective heating, as well as the structural parts suitable for mass transfer enhancement through ultrasonic cavitation ablation, were determined.

[0012] Step 2: Optimization of ultrasonic-microwave synergistic leaching process parameters;

[0013] Specifically, this includes: selecting a suitable acid leaching system based on the RDR chemical composition, uranium occurrence state, dielectric response, and acoustic response results obtained in step 1; the leaching system may include sulfuric acid, nitric acid, hydrochloric acid, or a combination thereof, and the type and concentration of acid may be further adjusted according to the composition of phosphates, silicates, and associated metal oxides in the RDR; mixing the RDR sample with the leaching solution at a preset liquid-solid ratio and placing it in an ultrasonic-microwave synergistic reaction device for enhanced leaching;

[0014] Using uranium leaching rate, residual uranium content in the residue, acid consumption, leaching time, and degree of residue structural damage as evaluation indicators, the effects of ultrasonic power, microwave power, synergistic action mode, leaching temperature, leaching time, acid concentration, and liquid-solid ratio on uranium leaching efficiency were systematically investigated. Ultrasonic power could range from 100 to 1000 W, microwave power from 100 to 5000 W, synergistic action modes could be simultaneous ultrasonic and microwave action, ultrasonic followed by microwave action, microwave followed by ultrasonic action, or intermittent alternating action, leaching temperature from 60 to 200 °C, leaching time from 0.5 to 6 h, acid concentration from 0.5 to 5 mol / L, and liquid-solid ratio from 2:1 to 10:1.

[0015] Single-factor experiments were used to preliminarily determine the effective range of the main influencing factors. Then, response surface methodology was used to establish a response relationship model between multiple factors and uranium leaching rate, and the main effects, interactions, and significance levels of each factor were analyzed. The optimal matching relationship between ultrasonic power, microwave power, temperature, acid concentration, and liquid-solid ratio was determined by response surface plots, contour plots, and analysis of variance. The uranium concentration in the leachate was determined by ICP-MS or ICP-OES, and the uranium leaching rate was calculated based on the total uranium in the original RDR. The residual uranium content was determined after digestion of the leaching residue to verify the degree of uranium release. Through the above optimization, a synergistic leaching process parameter combination that can achieve efficient uranium recovery with low acid consumption, short reaction time, and controllable residue properties was obtained.

[0016] Step 3, Mechanism of matrix dissociation in ultrasonic-microwave synergistic field;

[0017] Specifically, this includes: comparative characterization of typical residue samples after conventional acid leaching, single ultrasonic leaching, single microwave leaching, and ultrasonic-microwave synergistic leaching; XRD analysis of changes in silicates, phosphates, and other stable phases before and after leaching; SEM observation of particle surface corrosion, crack formation, pore development, and particle breakage; SEM-EDS or EPMA analysis of spatial distribution changes of uranium and elements such as Si, P, Ca, and Fe before and after leaching; BET analysis of changes in specific surface area, pore size distribution, and pore volume; and XPS analysis of changes in the surface chemical state of uranium and related elements.

[0018] By combining the dielectric parameters of each phase in the RDR, the electromagnetic field distribution, temperature field distribution and thermal stress evolution process of different mineral phases in the microwave field are simulated using COMSOL, HFSS or other multiphysics simulation software to determine the local selective heating region and thermal stress concentration location caused by dielectric differences; at the same time, the propagation, sound pressure distribution and cavitation intensity distribution of ultrasonic waves in the liquid-solid system are simulated to analyze the effect of shock waves generated by cavitation bubble collapse and microjets on the peeling of the coating layer on the particle surface.

[0019] By correlating experimental characterization results with multiphysics simulation results, the mechanism of ultrasound-microwave synergistic enhancement of leaching is elucidated. Microwave action induces selective heating and thermal stress cracking from within the particles, causing microcracks in the high-silicon / high-phosphorus matrix and increasing the exposure of the uranium phase. Ultrasonic action generates cavitation stripping, impact fragmentation, and interfacial mass transfer enhancement from the outside of the particles, further stripping away the cracked or loosened coating. Together, these two processes form a synergistic dissociation pathway: internal thermal stress cracking – external cavitation stripping – rapid penetration of the leaching agent – ​​migration and release of uranium. By establishing a leaching kinetic model, the chemical reaction control, diffusion control, and mixing control stages are further distinguished, demonstrating the contribution of the synergistic field effect to the leaching rate enhancement.

[0020] Step 4, Analysis of the characteristics of secondary leaching residue;

[0021] Specifically, the process includes: solid-liquid separation, washing, drying, and homogenization of the secondary leaching residue obtained under optimal synergistic leaching conditions; subsequent systematic determination of its chemical composition, residual uranium content, phase structure, particle size distribution, microstructure, pore structure, and dielectric properties; determination of residual uranium and other associated elements in the residue using ICP-MS or ICP-OES to evaluate the radioactivity reduction effect of the residue after uranium recovery; XRD analysis of the retention or transformation of silicates, phosphates, and other stable phases in the residue; SEM-EDS observation of the residue particle morphology and residual uranium element distribution; particle size analysis of the residue particle size distribution; BET or mercury intrusion porosimetry analysis of the residue pore structure; and determination of the residue dielectric properties using a vector network analyzer to provide parameter basis for subsequent microwave curing or stabilization treatment.

[0022] The residual uranium content, degree of encapsulation phase destruction, particle size change, specific surface area change, and dielectric response change of the secondary leaching residue are used as feedback indicators of the front-end leaching effect. If the residual uranium content in the residue is significantly reduced, and SEM, BET, and XRD results show that the encapsulation structure is destroyed, the mass transfer channels are increased, or the order of the stable encapsulation phase is reduced, it indicates that the ultrasonic-microwave synergistic field effectively promotes the exposure and release of encapsulated uranium. If the residue still contains a high proportion of refractory uranium, the ultrasonic power, microwave power, leaching temperature, acid concentration, or synergistic mode in step 2 are adjusted in reverse according to its phase composition and elemental distribution results.

[0023] The results of the secondary leaching residue characteristic analysis can also be used as input parameters for subsequent residue stabilization treatment; based on the content of Si, P, Al, Ca, Fe and residual uranium in the residue, it can be determined whether it is suitable as a raw material for glass-ceramic curing, phosphate curing or other stabilization treatments; based on the dielectric properties and particle size distribution of the residue, the heating behavior and molding conditions in the subsequent microwave curing process can be determined; thus, this invention achieves a dual evaluation of the front-end uranium recovery effect and the suitability for back-end safe treatment through secondary leaching residue analysis, forming a closed-loop technical route of characterization-leaching-dissociation-feedback.

[0024] Furthermore, the mineralogical characteristics and uranium occurrence state characterization of the RDR were as follows: XRD, SEM-EDS, EPMA and other methods were used to analyze the phase composition, microstructure and elemental distribution of the RDR; through stepwise chemical extraction combined with ICP-MS analysis, the occurrence forms of uranium in different phases were identified, and the proportion of encapsulated uranium and its stable phase were determined; the dielectric properties of the RDR and its main components were measured using a vector network analyzer to evaluate the microwave absorption capacity, and its acoustic characteristic parameters were measured to provide basic data for the design of synergistic enhancement processes.

[0025] Furthermore, the ultrasonic-microwave synergistic leaching process parameters were optimized as follows: leaching experiments were conducted in a self-developed multifunctional synergistic treatment experimental device to screen suitable leaching systems; the influence of ultrasonic power, microwave power, synergistic mode, leaching temperature, leaching time, acid concentration, and liquid-solid ratio on uranium leaching rate was systematically investigated using the response surface methodology, a response model of process parameters and leaching efficiency was established, and the optimal parameter combination was determined; the uranium concentration in the leaching solution was measured using ICP-MS.

[0026] Furthermore, the response surface methodology was used to systematically examine ultrasonic power (100-1000 W), microwave power (100-5000 W), synergistic mode (synchronous / stepwise), leaching temperature (60-200 ℃), leaching time (0.5-6 h), acid concentration (0.5-5 mol / L), and liquid-solid ratio (2:1-10:1).

[0027] Furthermore, the dissociation mechanism of the encapsulated matrix in the ultrasonic-microwave synergistic field is as follows: typical leaching residue samples are selected, and XRD is used to analyze phase evolution, SEM-EDS is used to observe changes in microstructure and microcrack formation and propagation characteristics, XPS is used to analyze changes in surface chemical state, and BET is used to analyze pore structure evolution; combined with temperature field simulation and cavitation field analysis, the dissociation mechanism of silicon / phosphorus encapsulated matrix by ultrasonic-microwave synergistic effect is elucidated, the synergistic strengthening mechanism of cavitation exfoliation-thermal stress cracking is revealed, and a leaching kinetic model is established.

[0028] Furthermore, the secondary leaching residue characteristics analysis: the leaching residue obtained under optimal process conditions is systematically characterized to clarify its chemical composition, phase structure, particle size distribution, dielectric properties and residual uranium content.

[0029] Another object of the present invention is to provide a uranium recovery system from high-silicon / high-phosphorus radioactive dissolution slag, comprising:

[0030] The state characterization module is used for RDR mineralogical characteristics and uranium occurrence state characterization;

[0031] The parameter optimization module is used to optimize the parameters of the ultrasonic-microwave synergistic leaching process.

[0032] Dissociation module for understanding the dissociation mechanism of encapsulated matrix in ultrasonic-microwave synergistic field;

[0033] The characteristic analysis module is used for the characteristic analysis of secondary leaching residue.

[0034] Based on the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solution to be protected by this invention are as follows:

[0035] Existing technologies have disclosed methods for enhancing uranium leaching using ultrasound, which promotes solid-liquid reactions and improves leaching efficiency through cavitation effects. Simultaneously, research exists on microwave or ultrasound-microwave combined methods as pretreatment or enhanced leaching, primarily aimed at improving mineral structure and increasing the efficiency of subsequent chemical leaching. Furthermore, traditional uranium recovery methods still mainly focus on acid leaching or leaching system optimization, concentrating on leaching agent ratios and process control. However, these existing technologies are generally limited to single enhancement methods or simple physical field combinations, and primarily target conventional ore systems, lacking targeted technical pathways for complex occurrence systems such as high-silicon / high-phosphorus radioactive dissolution slag.

[0036] Within a predetermined framework, this invention constructs a continuous process—characterization of RDR mineralogical features and uranium occurrence state, optimization of ultrasonic-microwave leaching parameters, dissociation mechanism of the matrix encapsulated in the synergistic field, and analysis of secondary leaching residue characteristics—to form an integrated technology chain encompassing characterization, enhanced leaching, mechanism analysis, and residue feedback.

[0037] This invention proposes an integrated and innovative technical route of ultrasonic-microwave synergistic enhancement of secondary leaching and microwave glass-ceramic solidification, aiming to achieve efficient recovery of uranium resources and stable disposal of residues.

[0038] This study investigates the dissociation and leaching of encapsulated uranium in RDR (Radiated Removal Diagnosis) enhanced by ultrasound and microwave. By analyzing the uranium's occurrence state and utilizing the synergistic effect of ultrasonic cavitation and microwave selective heating, the dissociation mechanism of cavitation stripping-thermal stress-induced cracking is revealed. Process parameters are optimized to achieve a uranium leaching rate ≥90%. The study also investigates the microwave glass-ceramic curing mechanism and process of the leaching residue. A glass-ceramic formulation is designed for high silicon and high phosphorus characteristics. The structural rearrangement and nuclide fixation mechanism of silicon / phosphorus components in the microwave field are elucidated, achieving a volume reduction rate ≥60% for the cured body. Furthermore, the long-term stability and nuclide retardation performance of the microwave-cured body are evaluated. The physical and mechanical properties, chemical stability, and radiation resistance of the cured body are systematically tested. A process-structure-performance correlation model is established, verifying a normalized leaching rate ≤1×10⁻⁶. -5 g·m -2 ·d -1 The independent research and development and integrated verification of the multifunctional ultrasonic-microwave synergistic processing experimental device, and the development of an experimental device that integrates synergistic enhancement of leaching and microwave sintering functions, provide platform support for process research.

[0039] The implementation of this invention will form a complete technical solution for RDR resource recovery and safe disposal. The research results can provide theoretical basis and technical support for the minimization of radioactive waste and the development of back-end technologies for the nuclear fuel cycle in my country, and have important scientific significance and engineering application value.

[0040] To address the challenge of effectively recovering uranium from tightly bound stable silicate / phosphate phases in RDR (Recovery by Drainage) leaching using conventional methods, this invention utilizes a synergistic ultrasonic-microwave enhancement technology to achieve deep dissociation of the encapsulated matrix. The cavitation effect of ultrasound generates intense microjets and shock waves at the liquid-solid interface, physically stripping the particle surface and enhancing mass transfer. The selective heating effect of microwaves induces thermal stress microcracks within the encapsulated matrix. This synergistic effect of internal and external processes forms a cavitation-stripping-thermal stress-induced cracking dissociation mechanism, significantly improving uranium accessibility and leaching efficiency. This technology is core to achieving the project's front-end resource recovery goals.

[0041] This invention employs multiphysics simulation software such as COMSOL to simulate the temperature distribution, thermal stress evolution, and acoustic field distribution of different phases in an ultrasonic-microwave synergistic field. Combined with measured data of dielectric and acoustic properties, it reveals the synergistic mechanism of microcrack nucleation and propagation with cavitation stripping. The disintegration behavior of the encapsulated matrix is ​​experimentally verified using SEM, XRD, and XPS. Based on this, an experiment is designed using the response surface methodology to systematically investigate the effects of key factors such as microwave power, ultrasonic power, synergistic mode, temperature, acid concentration, and liquid-to-solid ratio on uranium leaching rate. By combining artificial neural networks and genetic algorithms to globally optimize process parameters, the optimal parameter combination for uranium leaching rate ≥90% is obtained. The physicochemical properties of the leaching residue are systematically characterized, providing accurate raw material data for subsequent solidification research.

[0042] The expected benefits and commercial value of the technical solution of this invention after its transformation are as follows:

[0043] This invention addresses the practical problems of inefficient recovery of residual uranium from high-silicon / high-phosphorus radioactive dissolution slag and the high pressure of long-term temporary storage of waste slag. It proposes a core technical solution based on precise identification of uranium occurrence state, ultrasonic-microwave synergistic enhanced leaching, regulation of the matrix dissociation mechanism, and feedback on the characteristics of secondary leaching residue. After conversion, this solution can be used for the secondary resource recovery of radioactive dissolution slag in uranium purification and conversion, uranium mining and metallurgy, and related nuclear fuel cycle front-end processes. This will improve the efficiency of residual uranium recovery, reduce radioactive waste inventory, and lessen the burden of subsequent temporary storage, transportation, and final disposal.

[0044] Compared to simply storing or directly solidifying radioactive waste (RDRs), this invention prioritizes the recovery of uranium elements that still possess resource value, achieving the dual benefits of reducing radioactive waste at its source and recovering strategic resources. For RDRs with high uranium content and large stockpiles, this invention has the industrialization potential to develop engineered treatment process packages, dedicated co-leaching equipment, and supporting detection and evaluation methods. It can serve nuclear fuel cycle companies, uranium mining and metallurgical companies, and radioactive waste treatment units, possessing excellent technological transformation value and promising application prospects.

[0045] Furthermore, this invention, through systematic analysis of the composition, phase composition, particle size, dielectric properties, and residual uranium content of the secondary leaching residue, provides clear raw material parameters for subsequent stabilization, glass-ceramic solidification, or final disposal processes, thereby reducing uncertainties in subsequent disposal processes. This technical approach not only improves the economics of uranium resource recovery but also helps reduce the life-cycle management costs of radioactive waste, demonstrating high overall commercial value.

[0046] The technical solution of this invention fills a technological gap in the industry both domestically and internationally:

[0047] Current uranium recovery technologies primarily focus on conventional uranium ores, tailings, or uranium-containing materials that are relatively easy to leach. The key technological focus is typically on optimizing acid leaching systems, oxidant selection, leaching agent concentration, and leaching time. For high-silica / high-phosphorus radioactive dissolution slag, uranium often exists in the form of encapsulation or solid solution within stable inert phases such as silicates and phosphates. Conventional leaching systems struggle to effectively open these encapsulated structures, limiting uranium accessibility and leaching potential. Currently, there is a lack of systematic enhanced leaching methods for this type of complex secondary radioactive waste, with the dissociation of encapsulated uranium as the core objective.

[0048] This invention does not simply increase acid concentration or extend leaching time, but rather couples RDR mineralogical characteristics, uranium occurrence state, dielectric response, acoustic response, and ultrasonic-microwave synergistic field to establish a complete technical chain from phase identification to multi-field enhanced dissociation and then to residue feedback evaluation. This scheme combines ultrasonic cavitation ablation with microwave selective heating-induced thermal stress cracking to solve the problem of uranium exposure in high-silicon / high-phosphorus matrices, overcoming the technical limitations of traditional leaching methods that mainly rely on chemical reaction-driven processes.

[0049] Therefore, this invention fills the technical gap in ultrasonic-microwave synergistic dissociation and enhanced leaching of encapsulated uranium in high-silicon / high-phosphorus radioactive dissolution slag, and also fills the process gap in the integrated design of RDR occurrence state characterization, synergistic field parameter optimization, encapsulated matrix dissociation mechanism and secondary residue feedback evaluation.

[0050] The technical solution of this invention solves a technical problem that people have long desired to solve but have been unable to achieve:

[0051] High-silicon / high-phosphorus radioactive dissolution slag has long presented a contradiction: it possesses resource value but is difficult to recover, and it poses radioactive risks but is difficult to dispose of at low cost. On the one hand, a certain amount of uranium remains in the RDR, and direct temporary storage or disposal would result in resource waste; on the other hand, the uranium is encapsulated by stable silicates, phosphates, and multi-component inert mineral phases, making it difficult for conventional acid leaching to fully contact the target uranium phase. Even increasing acid concentration, temperature, or leaching time can easily lead to limited improvement in leaching efficiency, increased acid consumption, large residue volume, and a heavier burden on secondary waste liquid. Therefore, how to effectively release encapsulated uranium without solely relying on highly corrosive chemical conditions is a long-standing but challenging problem that the industry hopes to solve.

[0052] This invention proposes a synergistic dissociation pathway of internal cracking, external stripping, and enhanced mass transfer to address this challenge. Microwaves, acting on the interior of mineral particles with dielectric differences, induce localized selective heating and thermal stress concentration, causing microcracks in the silicon / phosphorus-encapsulated matrix. Ultrasonic waves generate cavitation, shock waves, and microjets in the liquid phase, continuously stripping the surface coating from the particles and enhancing mass transfer at the solid-liquid interface. The synergy of these two approaches promotes the gradual exposure of encapsulated uranium, transforming it into a more easily leached state, thus overcoming the core bottlenecks of traditional leaching processes: uranium not being exposed, acid contact difficulties, and reaction inhibition.

[0053] Meanwhile, this invention establishes a correlation model between process parameters and uranium leaching rate using the response surface methodology, and verifies the dissociation effect through analysis of the phase composition, morphology, porosity, and residual uranium content of the leaching residue. This avoids the problems of blind selection of process parameters, insufficient mechanistic explanation, and uncontrollable residue state inherent in traditional empirical leaching methods. Therefore, this invention provides a controllable, verifiable, and scalable technical path for the efficient recovery of uranium from high-silicon / high-phosphorus radioactive dissolution slag.

[0054] The technical solution of this invention overcomes technical bias:

[0055] In existing technologies, for uranium-containing waste encapsulated in stable, inert matrices such as high-silicon / high-phosphorus radioactive dissolution slag, it is generally believed that improving uranium leaching rates mainly depends on higher acid concentrations, stronger oxidation systems, higher temperatures, or longer reaction times. For residues that are difficult to leach, the approach tends to be direct solidification or long-term temporary storage. This understanding of technology easily leads to two biases: first, viewing RDRs as low-recovery-value, difficult-to-handle radioactive waste while ignoring the resource potential of residual uranium; second, attributing leaching enhancement primarily to enhanced chemical conditions while neglecting the decisive role of physical fields in the dissociation of the encapsulating matrix structure and the mass transfer process.

[0056] This invention overcomes the aforementioned technical biases. Instead of simply enhancing chemical leaching, it starts from the occurrence state and inclusion structure of uranium, using ultrasound and microwaves as active means to regulate mineral particle structure, crack evolution, and interfacial mass transfer. Microwave selective heating induces internal thermal stress-induced cracking, while ultrasonic cavitation achieves external exfoliation and enhanced mass transfer, transforming the leaching process from traditional chemical dissolution control to a synergistic control of structural dissociation and chemical leaching. This approach breaks through the conventional understanding that high-silicon / high-phosphorus residues can only be treated with strong acid and strong oxidation systems or directly solidified.

[0057] Furthermore, this invention does not simply regard secondary leaching residue as the final treatment endpoint, but rather uses it as an important feedback object for evaluating the degree of dissociation at the front end and connecting it with subsequent treatment processes. It uses indicators such as residual uranium content, phase structure, particle size distribution, and dielectric properties to inversely optimize the leaching process. This design overcomes the technical bias of traditional leaching processes that emphasize leachate recovery while neglecting the subsequent properties of the residue, thus creating a continuous connection between uranium recovery and safe residue disposal, demonstrating significant inventiveness and practical value. Attached Figure Description

[0058] Figure 1 This is a flowchart of a method for uranium recovery from high-silicon / high-phosphorus radioactive dissolution slag provided in an embodiment of the present invention.

[0059] Figure 2 This is a structural block diagram of a uranium recovery system in high-silicon / high-phosphorus radioactive dissolution slag provided in an embodiment of the present invention.

[0060] Figure 3 This is a schematic diagram of the acid leaching process of natural uranium ore and the generation process of radioactive dissolution residue provided in the embodiments of the present invention.

[0061] Figure 4 This is a schematic diagram of the ultrasonic-microwave synergistic enhanced leaching mechanism provided in the embodiments of the present invention.

[0062] Figure 5 This is the overall technical roadmap provided by the embodiments of the present invention.

[0063] Figure 6 This is a schematic diagram of the static leaching experiment of the cured powder provided in the embodiment of the present invention. Detailed Implementation

[0064] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0065] The method for uranium recovery from high-silicon, high-phosphorus radioactive dissolution slag provided in this invention includes:

[0066] High-silicon, high-phosphorus radioactive dissolution residue is mixed with acidic leachate to form a liquid-solid slurry;

[0067] In the same leaching process, microwave and ultrasonic fields are applied to the liquid-solid slurry. The microwave field utilizes the difference in dielectric response between different mineral phases in the high-silicon and high-phosphorus radioactive dissolution slag to form local selective heating and thermal stress concentration inside the particles, causing thermal stress cracking of the silicate-encapsulated matrix and phosphate-encapsulated matrix and forming microcracks. The ultrasonic field creates cavitation outside the particles, causing the shock waves and microjets generated by the collapse of cavitation bubbles to peel off the cracked or loosened silicate-encapsulated matrix and phosphate-encapsulated matrix, and enhances the mass transfer of the acidic leachate to the microcracks and the interior of the particles.

[0068] The encapsulated uranium enters the acidic leaching solution through the microcracks and peeling interface;

[0069] The leached liquid-solid slurry is subjected to solid-liquid separation to obtain uranium-containing leaching solution and secondary leaching residue.

[0070] In this embodiment of the invention, before forming the liquid-solid slurry, the contents of silicon, phosphorus, aluminum, calcium, iron, and uranium are determined by X-ray fluorescence spectroscopy or ICP-OES; the phase composition is analyzed by X-ray diffraction; the particle morphology and elemental spatial distribution are analyzed by scanning electron microscopy combined with energy dispersive spectroscopy, electron probe microanalysis, or micro-area Raman spectroscopy; the exchangeable state, carbonate-bound state, iron-manganese oxide-bound state, organic matter-bound state, and residual state of uranium are distinguished by stepwise chemical extraction combined with ICP-MS or ICP-OES; the dielectric constant, dielectric loss factor, and dielectric loss tangent are determined by vector network analysis; and the sound propagation characteristics, sound attenuation characteristics, or cavitation response characteristics are obtained by acoustic testing. Based on the measurement results, the mineral phase suitable for microwave selective heating, the encapsulation structure suitable for ultrasonic cavitation exfoliation, and the action parameters of the microwave field and the ultrasonic field are determined.

[0071] In this embodiment of the invention, the acidic leachate contains one or more of sulfuric acid, nitric acid, and hydrochloric acid; the microwave field and the ultrasonic field adopt a synergistic action mode of synchronous action, ultrasonic followed by microwave, microwave followed by ultrasonic, or intermittent alternating action; the ultrasonic power is 100~1000W, the microwave power is 100~5000W, the leaching temperature is 60~200 ℃, the leaching time is 0.5~6 h, the acid concentration is 0.5~5 mol / L, and the liquid-solid ratio is 2∶1 to 10∶1.

[0072] In this embodiment of the invention, uranium leaching rate, residual uranium content in the secondary leaching residue, acid consumption, leaching time, and degree of damage to the coating matrix are used as evaluation indicators. Single-factor experiments are used to determine the effective range of ultrasonic power, microwave power, leaching temperature, leaching time, acid concentration, and liquid-solid ratio. The response surface methodology is used to establish a response relationship model between the parameters and the uranium leaching rate. Based on the phase composition, spatial distribution of residual uranium, particle size distribution, pore structure, and dielectric response of the secondary leaching residue, the ultrasonic power, microwave power, leaching temperature, acid concentration, liquid-solid ratio, or synergistic mode are adjusted.

[0073] In this embodiment of the invention, the method further includes comparative characterization of residues obtained by acid leaching without ultrasonic and microwave fields, leaching with only ultrasonic fields, leaching with only microwave fields, and leaching with a combination of ultrasonic and microwave fields. X-ray diffraction is used to analyze phase evolution, scanning electron microscopy combined with energy dispersive spectroscopy is used to analyze particle surface corrosion, cracks, pores, and elemental spatial distribution, specific surface area analysis is used to determine specific surface area, pore size distribution, and pore volume, and X-ray photoelectron spectroscopy is used to analyze the surface chemical state of uranium, silicon, phosphorus, calcium, and iron. The electromagnetic field distribution, temperature field distribution, and thermal stress evolution in the microwave field are simulated based on dielectric parameters, and the sound pressure distribution and cavitation intensity distribution in the liquid-solid slurry are simulated based on acoustic parameters. A leaching kinetic model that distinguishes between chemical reaction control, diffusion control, and mixing control stages is established.

[0074] In this embodiment of the invention, the uranium recovery system from high-silicon, high-phosphorus radioactive dissolution slag includes:

[0075] The state characterization module is configured to obtain the phase composition, uranium occurrence morphology, uranium spatial distribution, dielectric response and acoustic response of high-silicon and high-phosphorus radioactive dissolution slag, and to determine the mineral phase suitable for microwave selective heating and the encapsulation structure suitable for ultrasonic cavitation exfoliation.

[0076] The parameter optimization module is configured to determine the acid leaching system, liquid-solid ratio, ultrasonic power, microwave power, synergistic mode, leaching temperature, and leaching time based on the results obtained by the state characterization module.

[0077] The dissociation module is configured to mix the high-silicon, high-phosphorus radioactive dissolution slag with acidic leachate to form a liquid-solid slurry, and apply microwave and ultrasonic fields to the liquid-solid slurry according to parameters determined by the parameter optimization module. By utilizing the difference in dielectric response between different mineral phases, local selective heating and thermal stress concentration are formed inside the particles, causing thermal stress cracking of the silicate-encapsulated matrix and phosphate-encapsulated matrix. Ultrasonic cavitation is used to peel off the cracked or loose silicate-encapsulated matrix and phosphate-encapsulated matrix outside the particles. The dissociation module is also configured to perform solid-liquid separation on the leached liquid-solid slurry to obtain uranium-containing leachate and secondary leaching residue.

[0078] The characteristic analysis module is configured to obtain the residual uranium content, phase structure, particle size distribution, microstructure, pore structure and dielectric properties of the secondary leaching residue, and provide the obtained results to the parameter optimization module.

[0079] In this embodiment of the invention, the state characterization module is configured to determine the chemical composition using X-ray fluorescence spectroscopy or ICP-OES, analyze the phase composition using X-ray diffraction, analyze the particle morphology and elemental spatial distribution using scanning electron microscopy combined with energy dispersive spectroscopy, electron probe microscopy, or micro-area Raman spectroscopy, analyze the uranium occurrence morphology using stepwise chemical extraction combined with ICP-MS or ICP-OES, determine the dielectric properties using vector network analysis, and obtain sound propagation characteristics, sound attenuation characteristics, or cavitation response characteristics using acoustic testing.

[0080] In this embodiment of the invention, the parameter optimization module is configured to determine the effective range of parameters using single-factor experiments, establish a response relationship model between ultrasonic power, microwave power, synergistic mode, leaching temperature, leaching time, acid concentration, liquid-solid ratio and uranium leaching rate using response surface methodology, and use uranium leaching rate, residual uranium content in secondary leaching residue, acid consumption, leaching time and degree of damage to the coating matrix as evaluation indicators for the parameter combination.

[0081] In this embodiment of the invention, the acidic leaching solution used in the dissociation module contains one or more of sulfuric acid, nitric acid, and hydrochloric acid; the ultrasonic power of the dissociation module is 100~1000 W, the microwave power is 100~5000 W, the leaching temperature is 60~200 ℃, the leaching time is 0.5~6 h, the acid concentration is 0.5~5 mol / L, the liquid-solid ratio is 2∶1 to 10∶1, and the synergistic action mode is one of synchronous action, ultrasonic followed by microwave, microwave followed by ultrasonic, or intermittent alternating action.

[0082] In this embodiment of the invention, the characteristic analysis module is configured to determine the residual uranium content using ICP-MS or ICP-OES, analyze the phase structure using X-ray diffraction, analyze the microstructure and spatial distribution of residual uranium using scanning electron microscopy combined with energy dispersive spectroscopy, determine the particle size distribution using particle size analysis, determine the pore structure using specific surface area analysis or mercury intrusion porosimetry, analyze the surface chemical state using X-ray photoelectron spectroscopy, and determine the dielectric properties using vector network analysis. The parameter optimization module is configured to adjust the ultrasonic power, microwave power, leaching temperature, acid concentration, liquid-solid ratio, or synergistic mode based on the results obtained by the characteristic analysis module.

[0083] like Figure 1 As shown in the figure, an embodiment of the present invention provides a method for uranium recovery from high-silicon / high-phosphorus radioactive dissolution slag, comprising the following steps:

[0084] S101, RDR mineralogical characteristics and uranium occurrence state characterization;

[0085] Specifically, the process includes: First, drying, crushing, grinding, and sieving the high-silicon / high-phosphorus radioactive dissolution slag to obtain a sample with a relatively uniform particle size distribution. Then, X-ray fluorescence spectroscopy or inductively coupled plasma atomic emission spectrometry is used to determine the overall chemical composition of Si, P, Al, Ca, Fe, U, and other associated elements in the RDR, clarifying its high-silicon, high-phosphorus, and uranium-containing characteristics. X-ray diffraction is used to analyze the main crystalline phase composition in the RDR, identifying silicates, phosphates, oxides, and other stable inert mineral phases. Scanning electron microscopy combined with energy dispersive spectroscopy is used to observe the microstructure, particle aggregation state, and elemental distribution characteristics of the RDR particles. If necessary, electron probe microanalysis or micro-area Raman spectroscopy is used to further determine the spatial co-distribution relationship between uranium and elements such as silicon, phosphorus, calcium, and iron.

[0086] By using stepwise chemical extraction combined with ICP-MS or ICP-OES analysis, the proportions of exchangeable, carbonate-bound, iron-manganese oxide-bound, organic matter-bound, and residual states of uranium in the RDR were distinguished, and the proportion of refractory uranium encapsulated by stable silicates or phosphates was determined. Based on the above test results, the correspondence between phase composition, uranium occurrence morphology, uranium spatial distribution, and leaching difficulty in the RDR was established, providing a basis for the subsequent design of ultrasonic-microwave synergistic enhanced leaching parameters.

[0087] Meanwhile, a vector network analyzer was used to determine the dielectric constant, dielectric loss factor, and dielectric loss tangent of the RDR and its main mineral components at microwave frequencies to evaluate the absorption capacity of different minerals relative to microwave energy. Acoustic testing methods were used to obtain the acoustic propagation, acoustic attenuation, or cavitation response characteristics of the RDR slurry or particle system, providing a basis for the selection of ultrasonic action parameters. Based on this, the components in the RDR suitable for thermal stress cracking induced by microwave selective heating, as well as the structural parts suitable for mass transfer enhancement through ultrasonic cavitation ablation, were determined.

[0088] S102, Optimization of ultrasonic-microwave synergistic leaching process parameters;

[0089] Specifically, this includes: selecting a suitable acid leaching system based on the RDR chemical composition, uranium occurrence state, dielectric response, and acoustic response results obtained in step 1; the leaching system may include sulfuric acid, nitric acid, hydrochloric acid, or a combination thereof, and the type and concentration of acid may be further adjusted according to the composition of phosphates, silicates, and associated metal oxides in the RDR; mixing the RDR sample with the leaching solution at a preset liquid-solid ratio and placing it in an ultrasonic-microwave synergistic reaction device for enhanced leaching;

[0090] Using uranium leaching rate, residual uranium content in the residue, acid consumption, leaching time, and degree of residue structural damage as evaluation indicators, the effects of ultrasonic power, microwave power, synergistic action mode, leaching temperature, leaching time, acid concentration, and liquid-solid ratio on uranium leaching efficiency were systematically investigated. Ultrasonic power could range from 100 to 1000 W, microwave power from 100 to 5000 W, synergistic action modes could be simultaneous ultrasonic and microwave action, ultrasonic followed by microwave action, microwave followed by ultrasonic action, or intermittent alternating action, leaching temperature from 60 to 200 °C, leaching time from 0.5 to 6 h, acid concentration from 0.5 to 5 mol / L, and liquid-solid ratio from 2:1 to 10:1.

[0091] Single-factor experiments were used to preliminarily determine the effective range of the main influencing factors. Then, response surface methodology was used to establish a response relationship model between multiple factors and uranium leaching rate, and the main effects, interactions, and significance levels of each factor were analyzed. The optimal matching relationship between ultrasonic power, microwave power, temperature, acid concentration, and liquid-solid ratio was determined by response surface plots, contour plots, and analysis of variance. The uranium concentration in the leachate was determined by ICP-MS or ICP-OES, and the uranium leaching rate was calculated based on the total uranium in the original RDR. The residual uranium content was determined after digestion of the leaching residue to verify the degree of uranium release. Through the above optimization, a synergistic leaching process parameter combination that can achieve efficient uranium recovery with low acid consumption, short reaction time, and controllable residue properties was obtained.

[0092] S103, Mechanism of matrix dissociation in ultrasonic-microwave synergistic field;

[0093] Specifically, this includes: comparative characterization of typical residue samples after conventional acid leaching, single ultrasonic leaching, single microwave leaching, and ultrasonic-microwave synergistic leaching; XRD analysis of changes in silicates, phosphates, and other stable phases before and after leaching; SEM observation of particle surface corrosion, crack formation, pore development, and particle breakage; SEM-EDS or EPMA analysis of spatial distribution changes of uranium and elements such as Si, P, Ca, and Fe before and after leaching; BET analysis of changes in specific surface area, pore size distribution, and pore volume; and XPS analysis of changes in the surface chemical state of uranium and related elements.

[0094] By combining the dielectric parameters of each phase in the RDR, the electromagnetic field distribution, temperature field distribution and thermal stress evolution process of different mineral phases in the microwave field are simulated using COMSOL, HFSS or other multiphysics simulation software to determine the local selective heating region and thermal stress concentration location caused by dielectric differences; at the same time, the propagation, sound pressure distribution and cavitation intensity distribution of ultrasonic waves in the liquid-solid system are simulated to analyze the effect of shock waves generated by cavitation bubble collapse and microjets on the peeling of the coating layer on the particle surface.

[0095] By correlating experimental characterization results with multiphysics simulation results, the mechanism of ultrasound-microwave synergistic enhancement of leaching is elucidated. Microwave action induces selective heating and thermal stress cracking from within the particles, causing microcracks in the high-silicon / high-phosphorus matrix and increasing the exposure of the uranium phase. Ultrasonic action generates cavitation stripping, impact fragmentation, and interfacial mass transfer enhancement from the outside of the particles, further stripping away the cracked or loosened coating. Together, these two processes form a synergistic dissociation pathway: internal thermal stress cracking – external cavitation stripping – rapid penetration of the leaching agent – ​​migration and release of uranium. By establishing a leaching kinetic model, the chemical reaction control, diffusion control, and mixing control stages are further distinguished, demonstrating the contribution of the synergistic field effect to the leaching rate enhancement.

[0096] S104, Characteristic analysis of secondary leaching residue;

[0097] Specifically, the process includes: solid-liquid separation, washing, drying, and homogenization of the secondary leaching residue obtained under optimal synergistic leaching conditions; subsequent systematic determination of its chemical composition, residual uranium content, phase structure, particle size distribution, microstructure, pore structure, and dielectric properties; determination of residual uranium and other associated elements in the residue using ICP-MS or ICP-OES to evaluate the radioactivity reduction effect of the residue after uranium recovery; XRD analysis of the retention or transformation of silicates, phosphates, and other stable phases in the residue; SEM-EDS observation of the residue particle morphology and residual uranium element distribution; particle size analysis of the residue particle size distribution; BET or mercury intrusion porosimetry analysis of the residue pore structure; and determination of the residue dielectric properties using a vector network analyzer to provide parameter basis for subsequent microwave curing or stabilization treatment.

[0098] The residual uranium content, degree of encapsulation phase destruction, particle size change, specific surface area change, and dielectric response change of the secondary leaching residue are used as feedback indicators of the front-end leaching effect. If the residual uranium content in the residue is significantly reduced, and SEM, BET, and XRD results show that the encapsulation structure is destroyed, the mass transfer channels are increased, or the order of the stable encapsulation phase is reduced, it indicates that the ultrasonic-microwave synergistic field effectively promotes the exposure and release of encapsulated uranium. If the residue still contains a high proportion of refractory uranium, the ultrasonic power, microwave power, leaching temperature, acid concentration, or synergistic mode in step 2 are adjusted in reverse according to its phase composition and elemental distribution results.

[0099] The results of the secondary leaching residue characteristic analysis can also be used as input parameters for subsequent residue stabilization treatment; based on the content of Si, P, Al, Ca, Fe and residual uranium in the residue, it can be determined whether it is suitable as a raw material for glass-ceramic curing, phosphate curing or other stabilization treatments; based on the dielectric properties and particle size distribution of the residue, the heating behavior and molding conditions in the subsequent microwave curing process can be determined; thus, this invention achieves a dual evaluation of the front-end uranium recovery effect and the suitability for back-end safe treatment through secondary leaching residue analysis, forming a closed-loop technical route of characterization-leaching-dissociation-feedback.

[0100] Firstly, in characterizing the mineralogical features and uranium occurrence states of S101RDR, a quantitative index system for the uranium occurrence state in RDR is further established. Specifically, parameters such as the distribution ratio of uranium in different mineral phases, the proportion of residual uranium, the spatial overlap between uranium and Si / P enrichment regions, the surface distribution intensity of uranium elements, and the U-O, U-P, or U-Si related binding states can be obtained through testing methods such as XRD, SEM-EDS, EPMA, XPS, stepwise chemical extraction, and ICP-MS. Furthermore, these results can be transformed into quantitative indicators that can be used for process design, such as the proportion of encapsulated uranium, the encapsulation strength of the silicon / phosphorus matrix, the uranium spatial dispersion coefficient, and the co-location coefficient of uranium with silicon / phosphorus elements. Through this quantitative index system, the main occurrence locations and encapsulation modes of difficult-to-leach uranium in RDR can be clearly identified, making the selection of subsequent ultrasonic-microwave synergistic leaching parameters no longer dependent on empirical judgment, but rather based on calculable, comparable, and controllable principles.

[0101] Secondly, between the optimization of the ultrasonic-microwave synergistic leaching process parameters in step S102 and the dissociation mechanism of the encapsulated matrix in the ultrasonic-microwave synergistic field in step 3, a coupling relationship between the synergistic field parameters and the dissociation effect of the encapsulated matrix is ​​further introduced. Specifically, parameters such as ultrasonic power, ultrasonic power density, sound pressure distribution, cavitation intensity, microwave power, microwave field strength, dielectric loss factor, heating rate, temperature gradient, and thermal stress intensity can be correlated with dissociation effect indicators such as uranium leaching rate, residual uranium content, microcrack density, particle fragmentation degree, specific surface area increment, and pore volume change. A functional relationship or semi-quantitative correlation model between the synergistic field input parameters, the encapsulated matrix structural response, and the uranium release efficiency can be constructed using response surface methodology, multiple regression, kinetic models, or multiphysics simulation methods. This design demonstrates that the ultrasonic-microwave synergistic effect of this invention is not a simple superposition, but rather achieves controllable dissociation of the high-silicon / high-phosphorus encapsulated matrix through parameter matching between acoustic cavitation stripping and microwave thermal stress cracking.

[0102] Thirdly, in the analysis of the characteristics of the secondary leaching residue of S104, traceable residue evaluation indicators are further introduced and used as the basis for reverse control of the front-end leaching process. Specifically, the actual damage to the encapsulated matrix caused by ultrasonic-microwave synergistic leaching can be evaluated by indicators such as residual uranium content, proportion of undissociated uranium, proportion of residual encapsulated uranium, degree of co-location of uranium with Si / P elements in the residue, retention rate of crystalline phase in the residue, microcrack density, pore structure evolution parameters, specific surface area change rate, and particle size change rate. If a high proportion of undissociated uranium still exists in the secondary leaching residue, parameters such as ultrasonic power, microwave power, synergistic action mode, leaching temperature, acid concentration, and liquid-solid ratio can be adjusted in reverse according to its corresponding phase, particle size, pore structure, and elemental distribution characteristics. Thus, step 4 is no longer just a result analysis of the leaching residue, but becomes a feedback loop for front-end process optimization, enabling this invention to form a closed-loop control technology route of occurrence identification—synergistic dissociation—leaching optimization—residue feedback—parameter correction.

[0103] Through the above optimizations, this invention further enhances the following inventive features without altering the original four-step technical route: First, it elevates the occurrence state of encapsulated uranium in RDR from qualitative description to quantitative identification; second, it elevates ultrasonic-microwave leaching from empirical parameter screening to coupled control of field effect and dissociation effect; third, it elevates secondary leaching residue analysis from end-stage detection to a basis for reverse optimization of the front-end process. These technical features collectively improve the mechanistic depth, parameter controllability, and engineering applicability of this invention, significantly enhancing its inventiveness compared to conventional acid leaching, single ultrasonic-enhanced leaching, or single microwave-enhanced leaching.

[0104] The mineralogical characteristics and uranium occurrence state characterization of RDR provided in this embodiment of the invention are as follows: XRD, SEM-EDS, EPMA and other methods are used to analyze the phase composition, microstructure and elemental distribution of RDR; through stepwise chemical extraction combined with ICP-MS analysis, the occurrence forms of uranium in different phases (exchangeable state, carbonate-bound state, iron-manganese oxide-bound state, and residue state) are identified, and the proportion of encapsulated uranium and its stable phase are determined; the dielectric properties (dielectric constant ε', dielectric loss factor ε'', dielectric loss tangent tanδ) of RDR and its main components are measured using a vector network analyzer to evaluate microwave absorption capacity, and its acoustic characteristic parameters are measured at the same time to provide basic data for synergistic enhancement process design.

[0105] The optimization of ultrasonic-microwave synergistic leaching process parameters provided in this embodiment of the invention involves: conducting leaching experiments in a self-developed multifunctional synergistic treatment experimental device to screen suitable leaching systems (sulfuric acid, nitric acid, hydrochloric acid, and combinations thereof); systematically investigating the influence of ultrasonic power, microwave power, synergistic mode, leaching temperature, leaching time, acid concentration, and liquid-solid ratio on uranium leaching rate using response surface methodology, establishing a response model between process parameters and leaching efficiency, and determining the optimal parameter combination; and measuring the uranium concentration in the leaching solution using ICP-MS.

[0106] The embodiments of this invention employ the response surface methodology to systematically investigate ultrasonic power of 100~1000 W; microwave power of 100~5000 W; synergistic mode of synchronous / stepwise; leaching temperature of 60~200 ℃; leaching time of 0.5~6 h; acid concentration of 0.5~5 mol / L; and liquid-solid ratio of 2:1~10:1.

[0107] The present invention provides a dissociation mechanism of the encapsulated matrix in an ultrasonic-microwave synergistic field: a typical leaching residue sample was selected, and XRD was used to analyze the phase evolution, SEM-EDS was used to observe the changes in microstructure and the characteristics of microcrack formation and propagation, XPS was used to analyze the changes in surface chemical state, and BET was used to analyze the evolution of pore structure; combined with temperature field simulation and cavitation field analysis, the dissociation mechanism of silicon / phosphorus encapsulated matrix by ultrasonic-microwave synergistic effect was elucidated, the synergistic strengthening mechanism of cavitation exfoliation-thermal stress cracking was revealed, and a leaching kinetic model was established.

[0108] The secondary leaching residue characteristic analysis provided in this embodiment of the invention: The leaching residue obtained under optimal process conditions is systematically characterized to clarify its chemical composition, phase structure, particle size distribution, dielectric properties and residual uranium content, providing raw material data for Project 2.

[0109] like Figure 2 As shown in the figure, an embodiment of the present invention provides a uranium recovery system from high-silicon / high-phosphorus radioactive dissolution slag, comprising:

[0110] The state characterization module is used for RDR mineralogical characteristics and uranium occurrence state characterization;

[0111] The parameter optimization module is used to optimize the parameters of the ultrasonic-microwave leaching process.

[0112] Dissociation module for understanding the dissociation mechanism of encapsulated matrix in ultrasonic-microwave synergistic field;

[0113] The characteristic analysis module is used for the characteristic analysis of secondary leaching residue.

[0114] Figure 3 This is a schematic diagram of the acid leaching process of natural uranium ore and the generation process of radioactive dissolution residue.

[0115] Figure 4 This is a schematic diagram of the synergistic enhancement mechanism of ultrasound and microwave leaching.

[0116] 1. Overall technical roadmap of the present invention (e.g.) Figure 5 (As shown) Based on an in-depth analysis of the challenges of RDR treatment: Uranium in RDR is tightly encapsulated by a stable silicon / phosphorus phase, resulting in low efficiency with conventional leaching methods. Furthermore, the high-silicon, high-phosphorus residue generated after leaching still requires safe disposal. A single technology cannot simultaneously address resource recovery and environmental safety; therefore, a synergistic leaching-solidification strategy is necessary. The application of ultrasonic-microwave synergy leverages its unique advantages—the cavitation effect of ultrasound can enhance mass transfer and stripping from the outside, while the selective heating of microwaves can generate thermal stress-induced cracking from the inside, forming a three-dimensional dissociation network through internal and external synergy; simultaneously, microwave heating can rapidly densify glass ceramics. The two physical fields exert a synergistic effect on the same technological platform. The technical route, with source reduction, stabilization, and safety assessment as its main lines and specialized equipment as its support, forms a research system with four interconnected research components:

[0117] Front-end resource recovery: By using ultrasonic-microwave synergistic enhanced leaching, efficient dissociation and recovery of encapsulated uranium is achieved, producing leaching residues with clear physicochemical properties, thus completing waste reduction at the source;

[0118] Back-end stabilization and solidification: Using leaching residue as raw material, microwave glass-ceramic solidification technology is used to transform it into a chemically stable solid body, thereby achieving effective fixation of radionuclides;

[0119] Safety verification: The physical and mechanical properties, chemical stability and radiation resistance of the microwave-cured body are evaluated, a process-structure-performance correlation model is established, and its long-term safety and reliability are verified.

[0120] Platform support: We have independently developed a multi-functional ultrasonic-microwave synergistic processing device that integrates synergistic leaching and microwave sintering functions, providing a dedicated platform for the research of the entire process.

[0121] 2. The device design is feasible, the module development is mature, and the platform support is reliable.

[0122] To support research on leaching and curing processes, this invention has independently developed a multifunctional experimental device integrating microwave-enhanced leaching and microwave sintering functions. The development of this device is supported by the following feasibility guarantees:

[0123] The technical design is feasible: Microwave heating technology is widely used in laboratories and industries, and the electromagnetic field distribution of the microwave resonant cavity can be accurately simulated and optimized using simulation software such as HFSS and COMSOL. Single-mode and multi-mode cavity design schemes are mature and can be tailored to the specific needs of leaching and sintering. The high-pressure acid-resistant reaction vessels (PTFE lining, quartz jars) required for the leaching module are already maturely used in microwave digestion systems; the high-temperature insulation structures (porous ceramics, fiber felt) and temperature measurement methods (infrared, thermocouples) required for the sintering module are widely used in microwave high-temperature furnaces. The device design is based on mature technology and faces no fundamental obstacles.

[0124] Complete manufacturing chain: The R&D team of this invention has established stable cooperative relationships with microwave equipment manufacturers, and can rely on the mature processing and manufacturing capabilities of these companies to complete the machining of the device, selection of microwave components, and system integration. Key components (microwave source, circulator, impedance modulator, temperature sensor, etc.) are all commercially available mature products, with smooth procurement channels and controllable manufacturing and assembly processes.

[0125] Standardized calibration methods: After the device is built, performance calibration can be performed using a standard system—water heating experiments to determine thermal efficiency and heating uniformity, standard glass sintering experiments to determine temperature uniformity and temperature control accuracy at high temperatures, and pressure resistance tests to verify the sealing performance of the leaching module. The calibration methods are simple and reliable, ensuring that the device performance meets research requirements and providing a stable and reliable platform for subsequent process experiments.

[0126] In summary, the design, manufacturing, and verification of this device are all adequately guaranteed, ensuring the smooth implementation of this invention and accumulating key design experience for subsequent engineering applications.

[0127] 3. Revealing the dual mechanism of dissociation-reconstruction of silicon / phosphorus matrix in microwave field

[0128] In the leaching process, the selective heating properties of microwaves are used to induce micro-regional thermal stress in the silicon / phosphorus encapsulated matrix, promoting the formation and propagation of microcracks and elucidating the enhanced dissociation mechanism of encapsulated uranium by microwave fields. In the solidification process, the rapid bulk heating properties of microwaves are used to reconstruct the glass network of silicon / phosphorus components, revealing the in-situ precipitation patterns of stable phases such as monazite and the coordination environment of residual nuclides. Through the integrated study of the dissociation-reconstruction dual mechanisms, a correlation model of leaching process, solidification parameters, microstructure, and macroscopic properties is established, providing a theoretical basis for the application of microwave technology in the treatment of complex radioactive waste.

[0129] 4. Independently developed a multifunctional microwave experimental device integrating leaching and curing.

[0130] To address the challenge of existing equipment simultaneously meeting the demands of complex processes involving strong acid leaching and high-temperature sintering, this invention presents a self-developed multifunctional microwave processing experimental device. This device integrates two main functional modules: microwave-enhanced leaching and microwave sintering, overcoming key technical challenges such as the design of pressure-resistant and corrosion-resistant reaction vessels, temperature uniformity control under high-temperature conditions, and precise measurement and control of multiple parameters. This device provides a dedicated platform for process optimization and mechanism research, while also accumulating key design parameters and operational experience for subsequent engineering applications.

[0131] 5. Evaluation of the long-term stability and radionuclide retardation performance of microwave-cured bodies

[0132] This invention conducts a system performance evaluation of the microwave-cured body prepared in step two, verifies its safety and reliability as a final disposal body, and establishes a process-structure-performance correlation model. The main research contents are as follows:

[0133] (1) Physical and mechanical property testing: The bulk density of the solidified body was determined by the Archimedes method (target ≥ 2.5 g / cm³). 3 ); Vickers hardness tester to determine hardness; DSC / TG thermal analysis to determine glass transition temperature and thermal stability; mercury intrusion porosimetry (MIP) to analyze pore structure characteristics (pore size distribution, porosity); universal testing machine to test compressive strength and elastic modulus.

[0134] (2) Chemical stability evaluation: Referring to ASTM C1285-21 (PCT-B) method, the cured powder pulverized to 100~200 mesh was soaked in deionized water at 90 °C for 42 days, the concentration of each element in the solution was measured, and the normalized leaching rate (L) was calculated. Ri Leaching experiments were conducted under different pH conditions (4, 7, 10) and different temperatures (40 ℃, 90 ℃) to study the influence of environmental factors on leaching behavior.

[0135] Figure 6 Schematic diagram of static leaching experiment of solidified powder

[0136] (3) Microstructure characterization: XRD was used to analyze phase changes before and after leaching; SEM-EDS was used to observe the microstructure and elemental distribution of the leached layer; TEM was used to observe the evolution of the nanoscale structure; XPS was used to analyze the changes in the surface chemical state; and Raman spectroscopy was used to analyze the changes in the glass network structure. By comparing the microstructures before and after leaching, the microscopic mechanism of element leaching was revealed.

[0137] (4) Radiation resistance stability study: Heavy ion irradiation (Au, Xe ions, energy MeV-GeV level) was used to simulate the radiation damage effect accumulated by α decay during long-term storage of the solidified body. The radiation resistance performance of the solidified body was evaluated by XRD analysis of the degree of amorphization before and after irradiation (calculation of amorphization dose), measurement of volume expansion rate, and TEM observation of microstructure. The correlation between irradiation dose and structural evolution and performance degradation was established.

[0138] 6. Independent research and development and integrated verification of a multifunctional ultrasonic-microwave synergistic processing experimental device

[0139] This invention addresses the experimental requirements of ultrasonic-microwave synergistic enhanced leaching and microwave sintering curing. A multifunctional experimental device integrating ultrasonic-microwave synergistic leaching and microwave sintering functions was independently developed, providing platform support for process research and accumulating design experience for engineering applications. The main research contents are as follows:

[0140] (1) Design and optimization of ultrasonic-microwave co-resonant cavity: The electromagnetic field distribution of different cavity structures was simulated and analyzed using software such as HFSS or COMSOL Multiphysics, while considering the placement and coupling method of the ultrasonic transducer. The compatibility between the ultrasonic probe and the microwave field was studied in detail to avoid mutual interference and ensure efficient energy transfer. Based on the simulation results, the optimal cavity size, energy feeding method and ultrasonic wave introduction structure were determined, taking into account the requirements of both co-leaching and sintering application scenarios. In the leaching process, the wave transmittance, sound conduction and acid corrosion resistance of the reaction vessel were considered, while in the sintering process, the heat preservation design and temperature uniformity at high temperature were considered.

[0141] (2) Design of a multifunctional reaction vessel: A multifunctional reaction module was developed to meet the different requirements of co-leaching and sintering. The co-leaching module adopts a double-layer structure design—the outer layer is a high-strength metal pressure-bearing shell, and the inner layer is a PTFE or quartz reaction vessel resistant to strong acids and high temperatures. The bottom or side wall of the vessel integrates an ultrasonic probe inlet interface to ensure effective transmission of acoustic energy; it is equipped with fiber optic temperature and pressure sensors, and the design working pressure is ≥3 MPa. The sintering module adopts a porous ceramic insulation structure, and is equipped with infrared temperature measurement or platinum-rhodium thermocouples to meet the requirements of high-temperature (≥1400 ℃) sintering, and a reserved atmosphere control interface is provided.

[0142] (3) Integration of Ultrasonic-Microwave Coordinated Measurement and Control System: A combination of fiber optic temperature measurement (suitable for the strong acid environment of the leaching module) and infrared temperature measurement (suitable for the high temperature environment of the sintering module) is adopted to achieve precise temperature monitoring of the reaction system. The ultrasonic generator and microwave source are controlled in coordination, which can realize flexible switching between synchronous or step-by-step operation modes. The pressure sensor monitors the pressure change in the leaching module in real time and sets overpressure alarm and automatic pressure relief protection. The control system adopts PLC or embedded system to realize closed-loop regulation of microwave power, continuous adjustable ultrasonic power (0~1000 W) and programmed control of heating curve. The temperature control accuracy is better than ±5℃, and process parameters such as temperature, pressure, power and time are recorded in real time.

[0143] (4) System integration and performance verification of the device: Integrate a microwave source (0~5 kW continuously adjustable, frequency 2.45 GHz), an ultrasonic generator (20~40 kHz, power 0~1000 W adjustable), a circulator, an impedance tuner, a temperature and pressure monitoring system, a control system, and other units to form a complete experimental device prototype. Performance calibration is performed using a standard system: water heating experiments determine thermal efficiency and heating uniformity; ultrasonic cavitation yield measurement experiments verify sound field distribution and cavitation intensity; standard glass sintering experiments determine temperature uniformity and temperature control accuracy at high temperatures; pressure resistance tests verify the sealing performance of the leaching module. Preliminary RDR-coordinated leaching and sintering verification experiments are conducted to verify the applicability and reliability of the device under actual process conditions, resulting in complete device design drawings, usage specifications, and maintenance manuals.

[0144] Combination Figures 4-6 This invention achieves efficient release of encapsulated uranium from a high-silicon / high-phosphorus matrix through a chain relationship of reaction device structure—multi-physics field input—particle dissociation evolution—leaching migration output.

[0145] like Figure 6 As shown, the system uses a constant-temperature experimental chamber as the external environment control unit to provide a stable temperature boundary and suppress environmental disturbances. Inside the chamber, an alloy reaction vessel is arranged, forming a sealed, pressure-resistant reaction space. A polytetrafluoroethylene (PTFE)-lined container is installed inside to hold the leachate and high-silicon / high-phosphorus radioactive dissolution slag samples. This lining structure isolates the corrosive medium from the metal vessel body while ensuring effective penetration and uniform coupling of microwave energy. Simultaneously, it provides a continuous liquid medium for ultrasonic wave propagation, thus forming a composite reaction cavity compatible with both microwave and ultrasonic fields.

[0146] In terms of mechanism of action, such as Figure 4As shown, microwave input, acting as a volumetric heating source, directly acts on the interior of mineral particles, causing selective absorption between different mineral phases due to dielectric differences. This creates a temperature gradient within the particles and induces thermal stress concentration, driving the initiation and propagation of microcracks. Simultaneously, ultrasonic input induces cavitation in the liquid phase, generating and collapsing numerous cavitation bubbles near the particle surface. This produces localized high-pressure shock waves and high-speed microjets, continuously impacting and peeling away the outer layer of the particle's structure. The synergistic effect of these two fields forms a coupled strengthening path of internal fracturing and external fragmentation: microwaves promote internal structural relaxation and crack propagation, while ultrasonic waves reduce external diffusion resistance and enhance interfacial mass transfer, gradually exposing the encapsulated uranium and causing it to migrate into the liquid phase, thus achieving the transformation from a solid-phase bound state to a leachable state.

[0147] like Figure 5 As shown, step 1 characterizes the mineral composition, crystal structure, and uranium occurrence state of the RDR, clarifying the input parameters. Step 2 synergistically optimizes ultrasonic power, microwave power, reaction temperature, and time to match the energy input with the mineral response characteristics. Step 3 establishes a dissociation mechanism model of the encapsulated matrix in the synergistic field, linking crack propagation, particle fragmentation, and uranium release. Step 4 uses phase and structure analysis of the secondary leaching residue to reverse-verify the relationship between the degree of pyrolysis and leaching efficiency, and adjusts the parameter settings accordingly. This forms a closed-loop enhanced leaching principle centered on structural support, multi-field coupling, mechanism-driven processes, and result feedback, achieving efficient recovery of uranium resources in high-silicon / high-phosphorus systems.

[0148] In the description of this invention, unless otherwise stated, "multiple" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," and "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0149] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for recovering uranium from high-silicon, high-phosphorus radioactive dissolution slag, characterized in that, include: High-silicon, high-phosphorus radioactive dissolution residue is mixed with acidic leachate to form a liquid-solid slurry; In the same leaching process, microwave and ultrasonic fields are applied to the liquid-solid slurry. The microwave field utilizes the difference in dielectric response between different mineral phases in the high-silicon and high-phosphorus radioactive dissolution slag to form local selective heating and thermal stress concentration inside the particles, causing thermal stress cracking of the silicate-encapsulated matrix and phosphate-encapsulated matrix and forming microcracks. The ultrasonic field creates cavitation outside the particles, causing the shock waves and microjets generated by the collapse of cavitation bubbles to peel off the cracked or loosened silicate-encapsulated matrix and phosphate-encapsulated matrix, and enhances the mass transfer of the acidic leachate to the microcracks and the interior of the particles. The encapsulated uranium enters the acidic leaching solution through the microcracks and peeling interface; The leached liquid-solid slurry is subjected to solid-liquid separation to obtain uranium-containing leaching solution and secondary leaching residue.

2. The method for uranium recovery from high-silicon, high-phosphorus radioactive dissolution slag as described in claim 1, characterized in that, Before the formation of the liquid-solid slurry, the contents of silicon, phosphorus, aluminum, calcium, iron, and uranium are determined by X-ray fluorescence spectroscopy or ICP-OES. The phase composition is analyzed by X-ray diffraction. The particle morphology and elemental spatial distribution are analyzed by scanning electron microscopy combined with energy dispersive spectroscopy, electron probe microanalysis, or micro-area Raman spectroscopy. The exchangeable state, carbonate-bound state, iron-manganese oxide-bound state, organic matter-bound state, and residual state of uranium are distinguished by stepwise chemical extraction combined with ICP-MS or ICP-OES. The dielectric constant, dielectric loss factor, and dielectric loss tangent are determined by vector network analysis. The acoustic propagation characteristics, acoustic attenuation characteristics, or cavitation response characteristics are obtained by acoustic testing. Based on the measurement results, the mineral phase suitable for microwave selective heating, the encapsulation structure suitable for ultrasonic cavitation exfoliation, and the interaction parameters of the microwave field and the ultrasonic field are determined.

3. The method for uranium recovery from high-silicon, high-phosphorus radioactive dissolution slag as described in claim 1, characterized in that, The acidic leachate contains one or more of sulfuric acid, nitric acid, and hydrochloric acid; the microwave field and the ultrasonic field adopt a synergistic action mode of synchronous action, ultrasonic followed by microwave, microwave followed by ultrasonic, or intermittent alternating action; the ultrasonic power is 100~1000W, the microwave power is 100~5000W, the leaching temperature is 60~200 ℃, the leaching time is 0.5~6 h, the acid concentration is 0.5~5mol / L, and the liquid-solid ratio is 2∶1 to 10∶1.

4. The method for uranium recovery from high-silicon, high-phosphorus radioactive dissolution slag as described in claim 1, characterized in that, Using uranium leaching rate, residual uranium content in secondary leaching residue, acid consumption, leaching time, and degree of damage to the coating matrix as evaluation indicators, single-factor experiments were conducted to determine the effective ranges of ultrasonic power, microwave power, leaching temperature, leaching time, acid concentration, and liquid-solid ratio. Response surface methodology was used to establish a response relationship model between these parameters and uranium leaching rate. Based on the phase composition, spatial distribution of residual uranium, particle size distribution, pore structure, and dielectric response of the secondary leaching residue, ultrasonic power, microwave power, leaching temperature, acid concentration, liquid-solid ratio, or synergistic action mode were adjusted.

5. The method for uranium recovery from high-silicon, high-phosphorus radioactive dissolution slag as described in claim 1, characterized in that, It also includes comparative characterization of residues obtained from acid leaching without ultrasonic and microwave fields, leaching with only ultrasonic fields, leaching with only microwave fields, and leaching with a combination of ultrasonic and microwave fields. X-ray diffraction is used to analyze phase evolution, scanning electron microscopy combined with energy dispersive spectroscopy is used to analyze particle surface corrosion, cracks, pores, and elemental spatial distribution, specific surface area analysis is used to determine specific surface area, pore size distribution, and pore volume, and X-ray photoelectron spectroscopy is used to analyze the surface chemical state of uranium, silicon, phosphorus, calcium, and iron. Based on dielectric parameters, the electromagnetic field distribution, temperature field distribution, and thermal stress evolution in the microwave field are simulated, and based on acoustic parameters, the sound pressure distribution and cavitation intensity distribution in the liquid-solid slurry are simulated. A leaching kinetic model that distinguishes between chemical reaction control, diffusion control, and mixing control stages is established.

6. A uranium recovery system from high-silicon, high-phosphorus radioactive dissolution slag, characterized in that, include: The state characterization module is configured to obtain the phase composition, uranium occurrence morphology, uranium spatial distribution, dielectric response and acoustic response of high-silicon and high-phosphorus radioactive dissolution slag, and to determine the mineral phase suitable for microwave selective heating and the encapsulation structure suitable for ultrasonic cavitation exfoliation. The parameter optimization module is configured to determine the acid leaching system, liquid-solid ratio, ultrasonic power, microwave power, synergistic mode, leaching temperature, and leaching time based on the results obtained by the state characterization module. The dissociation module is configured to mix the high-silicon, high-phosphorus radioactive dissolution slag with acidic leachate to form a liquid-solid slurry, and apply microwave and ultrasonic fields to the liquid-solid slurry according to parameters determined by the parameter optimization module. By utilizing the difference in dielectric response between different mineral phases, local selective heating and thermal stress concentration are formed inside the particles, causing thermal stress cracking of the silicate-encapsulated matrix and phosphate-encapsulated matrix. Ultrasonic cavitation is used to peel off the cracked or loose silicate-encapsulated matrix and phosphate-encapsulated matrix outside the particles. The dissociation module is also configured to perform solid-liquid separation on the leached liquid-solid slurry to obtain uranium-containing leachate and secondary leaching residue. The characteristic analysis module is configured to obtain the residual uranium content, phase structure, particle size distribution, microstructure, pore structure and dielectric properties of the secondary leaching residue, and provide the obtained results to the parameter optimization module.

7. The uranium recovery system from high-silicon, high-phosphorus radioactive dissolution slag as described in claim 6, characterized in that, The state characterization module is configured to determine the chemical composition using X-ray fluorescence spectroscopy or ICP-OES, analyze the phase composition using X-ray diffraction, analyze the particle morphology and elemental spatial distribution using scanning electron microscopy combined with energy dispersive spectroscopy, electron probe microscopy, or micro-area Raman spectroscopy, analyze the uranium occurrence morphology using stepwise chemical extraction combined with ICP-MS or ICP-OES, determine the dielectric properties using vector network analysis, and obtain sound propagation characteristics, sound attenuation characteristics, or cavitation response characteristics using acoustic testing.

8. The uranium recovery system from high-silicon, high-phosphorus radioactive dissolution slag as described in claim 6, characterized in that, The parameter optimization module is configured to determine the effective range of parameters using single-factor experiments, establish a response relationship model between ultrasonic power, microwave power, synergistic mode, leaching temperature, leaching time, acid concentration, liquid-solid ratio and uranium leaching rate using response surface methodology, and use uranium leaching rate, residual uranium content in secondary leaching residue, acid consumption, leaching time and degree of damage to the coating matrix as evaluation indicators for the parameter combination.

9. The uranium recovery system from high-silicon, high-phosphorus radioactive dissolution slag as described in claim 6, characterized in that, The acidic leaching solution used in the dissociation module contains one or more of sulfuric acid, nitric acid, and hydrochloric acid; the ultrasonic power of the dissociation module is 100~1000 W, the microwave power is 100~5000 W, the leaching temperature is 60~200 ℃, the leaching time is 0.5~6 h, the acid concentration is 0.5~5 mol / L, the liquid-solid ratio is 2∶1 to 10∶1, and the synergistic action mode is one of synchronous action, ultrasonic followed by microwave, microwave followed by ultrasonic, or intermittent alternating action.

10. The uranium recovery system from high-silicon, high-phosphorus radioactive dissolution slag as described in claim 6, characterized in that, The characteristic analysis module is configured to determine the residual uranium content using ICP-MS or ICP-OES, analyze the phase structure using X-ray diffraction, analyze the microstructure and spatial distribution of residual uranium using scanning electron microscopy combined with energy dispersive spectroscopy, determine the particle size distribution using particle size analysis, determine the pore structure using specific surface area analysis or mercury porosimetry, analyze the surface chemical state using X-ray photoelectron spectroscopy, and determine the dielectric properties using vector network analysis. The parameter optimization module is configured to adjust the ultrasonic power, microwave power, leaching temperature, acid concentration, liquid-solid ratio, or synergistic mode based on the results obtained from the characteristic analysis module.

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