Method for optimizing high-sulfur slag cavitation dissociation reactor

Abstract

The invention discloses a method for optimizing a high-sulfur slag cavitation dissociation reactor, which comprises the following steps of: constructing a geometric model of a fluid computational domain of the high-sulfur slag cavitation dissociation reactor on the basis of basic structure size parameters of the high-sulfur slag cavitation dissociation reactor; determining a reaction control equation of the geometric model; setting operation parameters of the geometric model, and performing grid division on the geometric model; carrying out analogue simulation calculation on the basis of a geometric model of grid division to obtain reaction parameters in the high-sulfur slag cavitation dissociation reactor, and obtaining a cavitation dissociation effect in the reactor according to the reaction parameters and taking the cavitation dissociation effect as an optimization basis; and adjusting the structure parameters and / or operation parameters of the reactor based on the optimization basis, performing simulation according to the above mode, judging whether the optimization basis reaches the preset condition, and if not, continuing to adjust the structure parameters and / or operation parameters of the reactor until the preset condition is reached. The method can assist in ascertaining the influence law and interaction mechanism of the multiphase multi-field system monomer mineral phase dissociation degree.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrometallurgy of zinc, and particularly to an optimization method for a cavitation dissociation reactor of high-sulfur slag. Background Art

[0002] Zinc is a metal commonly used in people's lives and is widely used in industrial applications such as galvanizing, alloy preparation, and manufacturing zinc-manganese batteries. As the mainstream metallurgical process for zinc sulfide concentrate at present, the leaching methods in the hydrometallurgy of zinc process are divided into conventional hydrometallurgy of zinc (roasting-leaching-purification-electrowinning) and oxygen pressure leaching process (oxygen pressure / atmospheric pressure leaching-purification-electrowinning). Since the oxygen pressure leaching process directly conducts the leaching process, saving the resource waste and environmental pollution of oxidative roasting, the sulfur element directly enters the leaching residue in the form of sulfur. The oxygen pressure leaching process method avoids the sulfur element entering the roasting flue gas to cause pollution. At the same time, compared with sulfuric acid products, the produced sulfur products are not only more convenient for transportation for smelting enterprises, but also have relatively stable market prices. Effectively extracting elemental sulfur from the oxygen pressure leaching residue is not only the advantage of the oxygen pressure leaching process, but also of great significance for the comprehensive utilization of valuable components in the oxygen pressure leaching residue in the future.

[0003] When a cavitation bubble grows to a certain stage or undergoes a huge pressure change, it will enter an unstable state and then collapse. The energy of the cavitation bubble collapse is mainly diffused in the surrounding fluid in the form of mechanical effect and thermal effect. The energy of the cavitation bubble collapse will act on the surrounding phases. For example, when it collapses in a liquid, a huge shock wave and water jet will be formed, and when it collapses near a solid wall surface, a huge impact force will also be generated on it. When the combination of mineral phase components is unstable, the energy of the cavitation bubble collapse will greatly exacerbate the unstable state of the mineral, and then cause an impact force in the opposite direction of the acting force between different phase components, resulting in the separation of components, that is, the cavitation dissociation of minerals.

[0004] During the process of cavitation dissociation, temperature is an important factor determining the dissociation effect of minerals. The influence of the thermal effect is mainly determined by the distance from the center of the air bubble: (1) In a cavitation bubble with water as the liquid phase, the highest temperature of the gas can reach 5200K, while in silicone oil it is 5075K; (2) On the contact surface, in the thin liquid layer near the collapsing bubble, the temperature can be as high as 1900K; (3) In a liquid medium, the collapse of the bubble will not directly affect the temperature of the medium.

[0005] The cavitation dissociation of valuable minerals is a non-classical gas-liquid-solid three-phase flow process. In the dissociation reactor, cavitation bubbles, water in the pulp, and solid-phase suspended ore particles exist. Due to the complex interaction processes among the gas-liquid-solid three phases during mineral dissociation, coupled with the difficulties and limitations of multiphase detection techniques, scientific research in the laboratory is very difficult and the data obtained is limited. The high-sulfur slag in zinc smelting has the characteristics of small particle size and ore phase inclusion and embedding, making it difficult to effectively separate. The traditional conditional experimental method is difficult to observe the microscopic morphology of the ore phase, resulting in the inability to clarify the specific physical processes during cavitation dissociation. At the same time, due to the presence of many toxic element compounds with large differences in hydrophobicity in the slag phase, the traditional experimental scheme with multiple conditions leads to huge consumption of consumables with little effect. However, due to the progress of statistical fluid mechanics research and statistical application software, it has become possible to use numerical simulation methods to explore the simplest multiphase flow phenomena.

[0006] Currently, the annual production capacity of electrolytic zinc by the direct leaching process used in domestic zinc smelting is about 500,000 tons, and about 600,000 tons of high-sulfur slag can be produced annually. In the high-sulfur slag, in addition to elemental sulfur, it also contains valuable components such as zinc, lead, silver, indium, as well as toxic substances such as arsenic, cadmium, and mercury. The safe disposal of high-sulfur slag has double significance for comprehensive resource utilization and environmental protection. The currently commonly used "flotation - hot filtration" process in refined zinc production has drawbacks such as low direct recovery rate of elemental sulfur, poor combined extraction effect of valuable components, and imperfect treatment of toxic elements, and urgent technical transformation and innovation are needed.

[0007] In recent years, the gradually emerging cavitation dissociation technology has the advantages of being fast, efficient, clean product, and pollution-free in the extraction of valuable components, and has broad application prospects in the field of solid waste treatment. However, in the actual process, a large number of process conditions will affect the efficiency of cavitation bubble dissociation of elemental sulfur in high-sulfur slag. Currently, the research on this kind of influence mainly stays in the aspect of fluid dynamics, and less attention is paid to the mechanism and industrial application. Therefore, it is of great significance to improve the influence mechanism of various process conditions on cavitation bubble dissociation of high-sulfur slag.

[0008] A large number of studies have shown that the cavitation dissociation of high-sulfur slag is a three-phase flow process of gas, liquid and solid, corresponding to the gas phase of cavitation bubbles, the aqueous solution phase in the pulp and the solid phase of high-sulfur slag particles respectively. Since the cavitation dissociation mechanism of minerals is not yet clear, and the interaction process of gas, liquid and solid is very complex, it is impossible to collect data on the internal flow field distribution of the cavitation dissociation reactor using existing scientific and technological means, making it very difficult to complete the cavitation dissociation process of high-sulfur slag with traditional experimental schemes. High-sulfur slag in zinc smelting has the characteristics of small particle size and mineral phase inclusion and embedding, making it difficult to effectively separate. Traditional conditional experimental methods are difficult to observe the microscopic morphology of the mineral phase, resulting in the inability to clarify the specific physical processes during the cavitation dissociation process. At the same time, due to the presence of a large number of toxic element compounds with large hydrophobicity differences in the slag phase, the traditional experimental scheme with multiple conditions leads to huge consumption and little effect. With the development of computational fluid dynamics and computer hardware, it has become possible to study the new three-phase flow interaction process in numerical models.

[0009] Therefore, there is an urgent need for a method that can explore the influence law of monomer mineral phase dissociation degree and the interaction mechanism in a multiphase and multi-field system by numerical simulation of the cavitation dissociation process, strengthen the efficient separation of elemental sulfur and other mineral phases, and realize the synergistic extraction of valuable components from high-sulfur slag and the safe dissociation of toxic elements. Summary of the Invention

[0010] Aiming at the deficiencies of the existing technology, the present invention provides an optimization method for a high-sulfur slag cavitation dissociation reactor, which can simulate the internal flow field distribution of the cavitation dissociation reactor, further understand the cavitation dissociation mechanism of minerals, and explore the influence law of monomer mineral phase dissociation degree and the interaction mechanism in a multiphase and multi-field system.

[0011] In the first aspect, the present invention proposes an optimization method for a high-sulfur slag cavitation dissociation reactor, including:

[0012] S1: Based on the basic structural dimension parameters of the high-sulfur slag cavitation dissociation reactor, construct a geometric model of the fluid calculation domain of the high-sulfur slag cavitation dissociation reactor;

[0013] S2: Determine the reaction control equation of the geometric model, which is used to simulate the cavitation dissociation process of high-sulfur slag in the reactor;

[0014] S3: Set the operating parameters of the geometric model and perform grid division on the geometric model; wherein, the operating parameters include the corresponding boundary conditions and parameter initial values;

[0015] S4: Based on the geometric model with grid division, perform simulation calculation to obtain the reaction parameters inside the high-sulfur slag cavitation dissociation reactor, and obtain the cavitation dissociation effect inside the reactor according to the reaction parameters as the optimization basis;

[0016] S5: Adjust the structural parameters and / or operating parameters of the reactor based on the optimization criterion, then perform simulation in the aforesaid manner, and determine whether the optimization criterion reaches the preset condition. If not, continue to adjust the structural parameters and / or operating parameters of the reactor until the preset condition is reached.

[0017] Further, in S2, for the mass transfer process of the geometric model, the reaction control equations set include:

[0018] Material flux vector equation in the high-sulfur slag pyrolysis dissociation reactor:

[0019]

[0020] In the formula, i refers to substance i in the high-sulfur slag pyrolysis dissociation reactor; N i is the material flux vector in the high-sulfur slag pyrolysis dissociation reactor; D i is the diffusion coefficient of the substance in the high-sulfur slag pyrolysis dissociation reactor; c i is the concentration of the substance in the high-sulfur slag pyrolysis dissociation reactor; is the sum of the first-order partial differentials of the substance concentration c i in three directions; u is the material fluid velocity vector in the high-sulfur slag pyrolysis dissociation reactor;

[0021] Material balance control equation:

[0022]

[0023] In the formula, is the Laplace operator; R i represents the substance reaction rate;

[0024] In the geometric model, the multiphase flow model, the turbulence model and the interphase force model are important components of the two-phase flow model. The Eulerian model can be used to construct models for many individually acting phases, and such phases may basically be liquids, gases or solids composed of any components. The Eulerian mode is also applied to the simulation of two-phase flows such as bubble columns and fluidized beds.

[0025] The continuity equation is:

[0026]

[0027] Among them, q is the q phase; a q is the volume fraction of the q phase; ρ q is the density of the q phase; is the flow velocity of the q phase; is the mass transfer from the p phase to the q phase; is the mass transfer from the q phase to the p phase; S qis the mass source term for the q-phase; n is the number of terms;

[0028] The momentum equation is:

[0029]

[0030]

[0031] where τ q is the stress-strain tensor for the q-phase; is the acceleration due to gravity; is the interphase exchange coefficient; are all interphase velocities; is the body force; is the lift force; is the wall lubrication force; is the virtual mass force; is the turbulent dispersion force;

[0032] The energy equation is:

[0033]

[0034] where h q is the specific enthalpy of the q-phase; is the shear viscosity of the q-phase; is the heat flux of the q-phase; Q pq is the heat exchange rate between the p- and q-phases; is the mass transfer from the p-phase to the q-phase; is the mass transfer from the q-phase to the p-phase; h pq is the difference in specific enthalpy between the p- and q-phases; h pq is the difference in specific enthalpy between the q- and p-phases.

[0035] Specifically, the Eulerian model considers the continuous phase and the dispersed phase separately. In the space within the time range of both, there are corresponding rates, temperatures, and pressures, and they will transfer and slide with each other.

[0036] The calculation formula for the virtual mass force is:

[0037]

[0038] where is the virtual mass force; C VM is the model constant; a l is the liquid volume fraction; ρ g is the gas density; is the gas flow velocity; is the liquid flow velocity; D / D tIt is the substantial derivative of two phases. The virtual mass force is equivalent to a driving force applied to the foam, specifically manifested as the cavitation bubble occupying a certain space of the surrounding liquid when moving in the liquid and simultaneously showing an accelerating motion.

[0039] The calculation formula for the lift force is:

[0040]

[0041] Where, is the lift force; a g is the gas volume fraction; ρ l is the liquid phase density; C L is the lift force model constant; is the gas phase flow velocity; is the liquid phase flow velocity. The shear action between liquid phases is studied by utilizing the lift force.

[0042] The calculation formula for the drag force is:

[0043]

[0044] Where, F D,l is the liquid phase drag force; F D,g is the gas phase drag force; ρ l is the liquid phase density; a g is the gas volume fraction; a l is the liquid phase volume fraction; C D is the drag coefficient; d b is the bubble diameter; is the gas phase flow velocity; is the liquid phase flow velocity. Usually, a dispersion phase accumulation rate is used to represent the drag force.

[0045] By establishing combinations of different inter-phase force models for numerical simulation, the gas phase distribution results are obtained.

[0046] Furthermore, the cavitation dissociation reactor adopts a round orifice jet, and the Standard k-ε model is selected as the turbulence model. The transport equation of the Standard k-ε model is:

[0047]

[0048] Where, ρ is the fluid density; k is the turbulent kinetic energy; u i is the component of the fluid velocity in the i direction; x i is the component of the spatial coordinate in the i direction; x j is the component of the spatial coordinate in the j direction; μ is the viscosity; μ t is the turbulent viscosity; σ k is the turbulent Prandtl number of the turbulent kinetic energy; G kis the turbulent kinetic energy caused by the average velocity gradient; G b is the turbulent kinetic energy generated by buoyancy; ε is the turbulent energy dissipation rate; Y M is the contribution of the fluctuating expansion of compressible turbulence to the total dissipation rate; S k is the source term;

[0049] The turbulent viscosity μ T can be expressed as:

[0050]

[0051] where ρ is the fluid density; k is the turbulent kinetic energy; ε is the turbulent energy dissipation rate; where k and ε satisfy:

[0052]

[0053] In the formula, the derivative term P k satisfies:

[0054]

[0055] where C μ , σ k , σ ε , C ε1 , C ε2 , and C ε are all model parameters.

[0056] Furthermore, the mineral phase dissociation equation at the gas-liquid interface is specifically as follows:

[0057] Mineral phase dissociation equation at the gas interface:

[0058]

[0059] Mineral phase dissociation equation at the liquid interface:

[0060]

[0061] where α is the two-phase volume fraction, n is the two-phase high-sulfur slag particle concentration, and φ is the two-phase transfer source term.

[0062] Even further, the collision frequency model in the cavitation dissociation process is:

[0063]

[0064] where r collision is the collision frequency; n l is the particle concentration; n g is the cavitation bubble concentration; z pb is the collision frequency coefficient (dimensionless) between particles and bubbles; d p is the particle diameter; db is the bubble diameter; U p is the particle turbulent pulse flow velocity; U b represents the cavitation turbulent pulse flow velocity.

[0065] Furthermore, the dissociation energy between the gas phase and the liquid phase is:

[0066]

[0067] where E dissociation is the dissociation energy; D is the effective distance between two surfaces; ε is the relative dielectric constant; ε0 is the medium constant in vacuum; R is the solid state; T is the temperature; R s is the equivalent zero-point five diameter; κ is the DebyeHtckel (Debye) parameter; F is the Faraday constant; ψ δ is the voltage at the start surface of the diffusion layer.

[0068] Furthermore, the dissociation probability in the cavitation dissociation process is:

[0069]

[0070] where p a is the dissociation probability in the cavitation dissociation process; Re b is the Reynolds number of the bubble; U b represents the cavitation turbulent pulse flow velocity; t ind is the induction time, that is, the time required for the ore particle to reach stable attachment after contacting the bubble; E dissociation (D) is the dissociation energy; d p is the particle diameter; d b is the bubble diameter;; E collapse is the bubble collapse energy.

[0071] Furthermore, the boundary conditions and parameter initial values in S3 include: the boundary conditions and initial values of the flow field, and the boundary conditions and initial values of the concentration field in the reactor;

[0072] The initial values corresponding to the flow field include: the boundary positions of the gas phase inlet and outlet, the inflow velocity, the outflow velocity, and the pressure and gravity conditions in the calculation domain of the cavitation dissociation reactor;

[0073] The initial values corresponding to the concentration field in the reactor include: the initial overall regional substance concentration of the cavitation dissociation reactor.

[0074] Furthermore, the preset conditions achieved by the optimization basis in S5 are specifically:

[0075] The cavitation dissociation effect is judged by whether the volume cumulative distribution rate of high-sulfur slag particles is greater than or equal to a preset value: if so, it indicates that the preset conditions are met; if not, it indicates that the preset conditions are not met.

[0076] In a second aspect, the present invention provides an optimization system for a high-sulfur slag cavitation dissociation reactor, comprising:

[0077] A geometric model construction model: used to construct a geometric model of the fluid calculation domain of the high-sulfur slag cavitation dissociation reactor based on the basic structural dimension parameters of the high-sulfur slag cavitation dissociation reactor;

[0078] A reaction control equation determination module: used to determine the reaction control equation of the geometric model, and the reaction control equation is used to simulate the high-sulfur slag cavitation dissociation process in the reactor;

[0079] A parameter setting and simulation module: used to set the operating parameters of the geometric model and perform mesh division on the geometric model; wherein, the operating parameters include the corresponding boundary conditions and parameter initial values; used to perform simulation calculation based on the geometric model after mesh division to obtain the reaction parameters inside the high-sulfur slag cavitation dissociation reactor, and obtain the cavitation dissociation effect in the reactor based on the reaction parameters as the optimization basis;

[0080] A model optimization module: based on the optimization basis, adjust the structural parameters and / or operating parameters of the reactor in the parameter setting and simulation module, then perform simulation, and judge whether the optimization basis reaches the preset conditions. If not, continue to adjust the structural parameters and / or operating parameters of the reactor until the preset conditions are reached.

[0081] In a third aspect, the present invention provides an electronic terminal, comprising a processor and a memory, the memory stores a computer program, and the processor calls the computer program to execute the steps of the method as described above.

[0082] In a fourth aspect, the present invention provides a readable storage medium storing a computer program, and the computer program is called by a processor to execute the steps of the method as described above.

[0083] Beneficial effects

[0084] The present invention proposes an optimization method for a high-sulfur slag cavitation dissociation reactor. First, the method can simulate the flow field distribution in the cavitation dissociation reactor, and at the same time further understand the cavitation dissociation mechanism of minerals and clarify the specific physical processes during the cavitation dissociation process; second, the method uses the high-temperature, high-pressure, and high-speed shock waves formed by the collapse of cavitation bubbles to act on mineral particles to achieve effects such as extracting components and dissociating impurities; finally, the method explores the influence law and interaction mechanism of the dissociation degree of monomer ore phases in the multiphase and multi-field system through numerical simulation of the cavitation dissociation process, realizes the collaborative extraction of valuable components in high-sulfur slag and the safe dissociation of toxic elements, and effectively guarantees the sustainable development of the zinc smelting industry. Description of the drawings

[0085] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0086] Figure 1 It is a flowchart of an optimization method for a high-sulfur slag air dissociation reactor provided by an embodiment of the present invention;

[0087] Figure 2 Schematic diagram of the geometric structure of a high-sulfur slag air dissociation reactor;

[0088] Figure 3 It is a schematic diagram of the mesh division of a high-sulfur slag air dissociation reactor provided by an embodiment of the present invention;

[0089] Figure 4 It is a schematic diagram of high-sulfur slag particles in the control volume state provided by an embodiment of the present invention;

[0090] Figure 5 It is a distribution diagram of the bubble content at different diameters along different heights in the air dissociation reactor A provided by an embodiment of the present invention;

[0091] Figure 6 It is a distribution diagram of the bubble content at different diameters along different heights in the air dissociation reactor B provided by an embodiment of the present invention;

[0092] Figure 7 It is a vertical velocity diagram of the gas-liquid two-phase along the central axis in the air dissociation reactor A provided by an embodiment of the present invention;

[0093] Figure 8 It is a vertical velocity diagram of the gas-liquid two-phase along the central axis in the air dissociation reactor B provided by an embodiment of the present invention;

[0094] Figure 9 It is a vertical velocity diagram of height-diameter in the liquid phase of the air dissociation reactor A provided by an embodiment of the present invention;

[0095] Figure 10 It is a vertical velocity diagram of height-diameter in the liquid phase of the air dissociation reactor B provided by an embodiment of the present invention;

[0096] Figure 11 It is an influence diagram of the dissociation time on the particle size distribution of high-sulfur slag particles at the outlet; where, (a) 0s; (b) 60s; (c) 120s; (d) 180s; (e) 240s; (f) 300s;

[0097] Figure 12It is a graph showing the change of the solid content distribution in the dissociator with time provided by an embodiment of the present invention;

[0098] Figure 13 It is a graph showing the change of the velocity field in the dissociator with time provided by an embodiment of the present invention;

[0099] Figure 14 It is a trajectory graph of particles with a diameter of 100 μm in the dissociator provided by an embodiment of the present invention;

[0100] Figure 15 It is a graph showing the influence of the reactor temperature on the particle size distribution of high-sulfur slag particles at the outlet provided by an embodiment of the present invention; where, (a) 60 °C; (b) 70 °C; (c) 80 °C; (d) 90 °C;

[0101] Figure 16 It is a graph showing the influence of the gas mass flow rate on the particle size distribution of high-sulfur slag particles at the outlet provided by an embodiment of the present invention; where, (a) 1×10 -3 kg / s; (b) 3×10 -3 kg / s; (c) 6×10 -3 kg / s; (d) 1×10 -2 kg / s;

[0102] Figure 17 It is a graph showing the influence of the pulp concentration on the particle size distribution of high-sulfur slag particles at the outlet provided by an embodiment of the present invention; where, (a) 4 g / L; (b) 5 g / L; (c) 6 g / L; (d) 9 g / L. Detailed implementation manners

[0103] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other implementation manners obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope protected by the present invention.

[0104] As Figure 1 shown, the present invention provides an optimization method for a high-sulfur slag cavitation dissociation reactor, and proposes to use the high-temperature, high-pressure, and high-speed shock waves formed by the collapse of cavitation bubbles to act on mineral particles to achieve effects such as extracting components and dissociating impurities. It mainly includes the following steps:

[0105] S1: Based on the basic structural dimension parameters of the high-sulfur slag air dissociation reactor, construct the geometric model of the fluid calculation domain of the high-sulfur slag air dissociation reactor. Specifically: According to the basic dimension parameters of the high-sulfur slag air dissociation reactor under the preliminary structural design, establish the geometric model of the fluid calculation domain of the air dissociation reactor. The main purpose is to determine the main structure of the reactor and the positions of each inlet and outlet, and parameterize the basic dimensions of the air dissociation reactor and the position parameters of each inlet and outlet to construct the geometric model.

[0106] S2: Determine the reaction control equations of the geometric model, which are used to simulate the air dissociation process of high-sulfur slag in the reactor. Specifically: Determine the reaction control equations of the geometric model. In order to simulate the air dissociation process of high-sulfur slag in the reactor, the two-phase flow fields of gas phase and slag phase, the chemical reaction mass transfer field, the solid-phase coupling equation, etc. need to be coupled in the model.

[0107] S3: Set the operating parameters of the geometric model and perform mesh division on the geometric model; among them, the operating parameters include the corresponding boundary conditions and parameter initial values. Specifically: Perform three-dimensional geometric model setting of the reactor, and after completion, perform mesh division and evaluate the mesh quality. After the basic model is constructed, the physical field setting is mainly to connect the completed solid-phase coupling equation with the two-phase numerical model control equation, and at the same time set the corresponding parameters and boundary conditions.

[0108] S4: Based on the geometric model with mesh division, perform simulation calculations to obtain the reaction parameters inside the high-sulfur slag air dissociation reactor, and based on the reaction parameters, obtain the gas-liquid two-phase velocity distribution, gas phase distribution, and air dissociation effect. Specifically: Perform CFD finite element simulation calculations, solve the distribution characteristics of the model and the concentration distribution structure of the reaction substances, and obtain the air dissociation effect, gas-liquid two-phase velocity distribution, gas phase distribution, etc. inside the high-sulfur slag air dissociation reactor under the set operating parameters. For the calculation results, analyze the air dissociation effect of the high-sulfur slag air dissociation reactor under the current structural operating parameters and use it as the optimization basis.

[0109] S5: Adjust the structural parameters and / or operating parameters of the reactor based on the optimization criteria, then perform simulation in the aforesaid manner, and determine whether the optimization criteria reach the preset conditions. If not, continue to adjust the structural parameters and / or operating parameters of the reactor until the preset conditions are met. According to S4, after analyzing the reactor characteristics, further adjust the reactor structure and / or operating parameters according to the actual situation and design concept, that is, by changing the basic dimension parameters in S1 and / or the boundary conditions and initial values in S3. Specifically, there are: the basic shape and size of the high-sulfur slag vacuum dissociation reactor, the boundary positions of the gas-phase inlet and outlet, the inlet and outlet sizes and shapes, the gas-phase inflow velocity and outflow velocity, the gas-phase pressure, etc. Then perform simulation in the manner of S4, compare the calculated data obtained under different conditions until the design optimization results of the structural parameters and / or operating parameters of the high-sulfur slag vacuum dissociation reactor reach the purposes of extracting components and dissociating impurities, etc.

[0110] Example

[0111] Step 1: Based on the basic structural dimension parameters of the high-sulfur slag vacuum dissociation reactor under the preliminary structural design, construct a geometric model of the fluid calculation domain of the high-sulfur slag vacuum dissociation reactor as shown in Figure 2 In the figure. The reactor is an axisymmetric geometric shape. To reduce the calculation amount, perform equal-proportion scaling. As shown in Figure 2 In the figure, for the vacuum dissociation reactor A, gas-liquid co-current flow is adopted, the main body diameter is 11.5 cm, the height is 70 cm, a gas-phase inlet with a width of 1 cm is set at the top layer about 15 cm high, and the pulp is fed vertically downward at the top layer. For the vacuum dissociation reactor B, gas-liquid countercurrent flow is adopted, the main body diameter is 11.5 cm, the height is 70 cm, a gas-phase inlet with a width of 1 cm is set at the bottom layer about 15 cm high, and the pulp is fed vertically downward.

[0112] Step 1: Determine the reaction control equation of the geometric model, and the reaction control equation is used to simulate the high-sulfur slag vacuum dissociation process in the reactor. To simulate the high-sulfur slag vacuum dissociation process in the reactor, physical fields such as the two-phase flow field of gas phase and slag phase, chemical reaction mass transfer field, and vacuum dissociation need to be coupled in the model.

[0113] Specifically, the mass flux vector equation in the high-sulfur slag vacuum dissociation reactor:

[0114]

[0115] In the formula, i refers to the substance i in the high-sulfur slag vacuum dissociation reactor; N i is the mass flux vector in the high-sulfur slag vacuum dissociation reactor; D i is the diffusion coefficient of the substance in the high-sulfur slag vacuum dissociation reactor; c i is the concentration of the substance in the high-sulfur slag vacuum dissociation reactor; is the concentration c of a certain substance in the high-sulfur slag air dissociation reactor i is the sum of the first-order partial derivatives in three directions; u is the fluid velocity vector of the substance in the high-sulfur slag air dissociation reactor;

[0116] Material balance control equation:

[0117]

[0118] In the formula, is the Laplace operator; R i represents the substance reaction rate.

[0119] In the geometric model, the multiphase flow model, the turbulence model, and the interphase force model are important components of the two-phase flow model.

[0120] The Eulerian model can construct many individually acting phases. And such phases can basically be liquid, gas, or solid composed of any components. The Eulerian mode is also applied to the simulation of two-phase flows such as bubble columns and fluidized beds.

[0121] The continuity equation for phase q is:

[0122]

[0123] where q is phase q, and phase q includes liquid phase, gas phase, and solid phase; a q is the volume fraction of phase q; ρ q is the density of phase q; is the flow velocity of phase q; p is phase p; is the mass transfer from phase p to phase q; is the mass transfer from phase q to phase p; S q is the mass source term of phase q, which can be adjusted according to the actual situation during specific implementation. In this embodiment, it is 0; n is the number of terms;

[0124] The momentum equation is:

[0125]

[0126] where τ q is the stress-strain tensor of phase q; is the gravitational acceleration; is the interphase exchange coefficient; is the interphase velocity; is the body force; is the lift force; is the wall lubrication force; is the virtual mass force; is the turbulent dispersion force;

[0127] The energy equation is:

[0128]

[0129] Among them, h q is the specific enthalpy of phase q; is the shear viscosity of phase q; is the heat flux of phase q; Q pq is the heat exchange rate between phases p and q; is the mass transfer from phase p to phase q; is the mass transfer from phase q to phase p; h pq is the specific enthalpy difference between phases p and q; h qp is the specific enthalpy difference between phases q and p.

[0130] Specifically, the Eulerian model considers the continuous phase and the dispersed phase separately. In the time range of both, the space has corresponding rates, temperatures, and pressures, and they will transfer and slide with each other.

[0131] Furthermore, the virtual mass force model means that when the cavitation bubble moves in the liquid, it occupies a certain space of the surrounding liquid, and at the same time, an accelerated motion occurs. Therefore, to describe this process, the virtual mass force model is provided, which is equivalent to a driving force applied to the bubble. The calculation formula for the virtual mass force is:

[0132]

[0133] Among them, is the virtual mass force, that is, the virtual mass force model; C VM is the virtual mass force model constant, which can be adjusted according to the actual situation during specific implementation. In this embodiment, it is taken as 0.5; a l is the liquid volume fraction; ρ g is the gas density; is the gas flow velocity; is the liquid flow velocity; D / D t is the substantial derivative of the two phases; The lift model is used to study the shear action between the liquid phases.

[0134] The calculation formula for the lift is:

[0135]

[0136] Among them, is the lift, that is, the lift model; a g is the gas volume fraction; ρ l is the liquid density; C L is the lift model constant, which can be adjusted according to the actual situation during specific implementation. In this embodiment, it is taken as 0.5; is the gas flow velocity; is the liquid flow velocity. By using the lift to study the shear action between the liquid phases.

[0137] Drag force models usually use a formula that includes the cumulative rate of the dispersed phase to calculate the volume distribution ratio of the gas-liquid two-phase through the cumulative rate of the dispersed phase. The calculation formula for the drag force is as follows:

[0138]

[0139] Among them, F D,l is the liquid-phase drag force; F D,g is the gas-phase drag force; ρ l is the liquid-phase density; a g is the gas-phase volume fraction; a l is the liquid-phase volume fraction; C D is the drag coefficient; d b is the bubble diameter; is the gas-phase flow velocity; is the liquid-phase flow velocity. Usually, a formula that includes the cumulative rate of the dispersed phase is used to represent the drag force.

[0140] By establishing combinations of different interphase force models for numerical simulation, after obtaining the gas-phase distribution results, continue to compare with the verification experiment.

[0141] Furthermore, the air dissociation reactor uses a round orifice jet and selects the Standard k-ε model as the turbulence model. The transport equations of the Standard k-ε model are as follows:

[0142]

[0143] Among them, ρ is the fluid density; k is the turbulent kinetic energy; u i is the component of the fluid velocity in the i direction; x i is the component of the spatial coordinate in the i direction; x j is the component of the spatial coordinate in the j direction; μ is the viscosity; μ t is the turbulent viscosity; σ k is the turbulent Prandtl number of the turbulent kinetic energy; G k is the turbulent kinetic energy caused by the average velocity gradient; G b is the turbulent kinetic energy generated by buoyancy; ε is the turbulent energy dissipation rate; Y M is the contribution of the fluctuating expansion of the compressible turbulence to the total dissipation rate; S k is the source term;

[0144] Among them, the constants of the Standard k-ε model selected in this embodiment are shown in Table 1:

[0145] Table 1 Constants of the Standard k-ε Model

[0146]

[0147] Turbulent viscosity μ T can be expressed as:

[0148]

[0149] where ρ is the fluid density; k is the turbulent kinetic energy; ε is the turbulent energy dissipation rate; and k and ε satisfy:

[0150]

[0151] In the formula, the derivative term P k satisfies:

[0152]

[0153] where C μ , σ k , σ ε , C ε1 , C ε2 , and C ε are all model parameters.

[0154] Furthermore, the solid-phase coupling equation is the control equation of the numerical model for the mineral phase dissociation in the cavitation dissociation process. In the cavitation dissociation process, the microscopic processes of the high-sulfur slag particles colliding with the cavitating bubbles, the cavitating bubbles collapsing, and the high-sulfur slag particles dissociating are corresponding simplifications of the actual cavitation dissociation process. The dissociation process of the high-sulfur slag particles in the cavitation dissociation process is to visualize the high-sulfur slag particles generated in the cavitation dissociation process in the macroscopic multi-level particle concentration field by studying the dissociation process of the high-sulfur slag phase on the basis of the gas-solid two-phase flow and studying the processes of the cavitation bubbles colliding with and collapsing on the high-sulfur slag particles during the dissociation process.

[0155] More specifically, the main interaction processes between the fine particles and the cavitation reaction bubbles are all at the microscopic scale, and their interactions are in the main interaction domain of the particles. Taking the friction mainly caused by the inertial effect between the bubbles and the particles during the cavitation process in the cavitation reaction as the main interaction, the collision frequency model of the cavitation dissociation process is thus formed. Therefore, the collision frequency model in the cavitation dissociation process is:

[0156]

[0157] where r collision is the collision frequency; n l is the particle concentration; n g is the cavitation bubble concentration; z pb is the collision frequency coefficient (dimensionless) between the particles and the bubbles; d p is the particle diameter; d b is the bubble diameter; U p is the particle turbulent pulse flow velocity; Ub Represents the pulsatile flow velocity of cavitation turbulence.

[0158] U i The expression is:

[0159] Where, U i is the pulsatile flow velocity of turbulence between particles and cavitation; ε is the dissipation rate; d i is the diameter of the cavitation or particle; ρ i is the density of the cavitation or particle; v is the kinematic viscosity of the fluid; ρ f is the kinematic density of the fluid. v and ρ f are simultaneously applied to the full flow induced by inertial effect-induced collision.

[0160] The van der Waals force is a kind of solid-state force, including three parts: (a) the force between instantaneous dipoles; (b) the directional force between permanent magnetic dipoles (Keesom force); (c) the attractive force between permanent dipoles (Debye force). Due to the distance between the two interfaces, the performance of the three interactions decreases. Therefore, the van der Waals force is regarded as the common action of many objects in the magnetic field.

[0161] The force between two solid-phase planes without charge is called the van der Waals force, that is, F vdW , and its expression is:

[0162]

[0163] Where, F vdW is the van der Waals force; D is the effective distance between two solid-phase planes without charge; A eff is the Hamaker constant; R s is the equivalent half-diameter. The van der Waals force usually only acts in the relatively close area.

[0164] Furthermore, the van der Waals force is generated by the overlap of the diffusion surface, and the dissociation energy is obtained based on the pressure on the starting surface of the diffusion layer. The dissociation energy expressions for the gas phase and the liquid phase are:

[0165]

[0166] Where, E dissociation is the dissociation energy; D is the effective distance between the two surfaces; ε is the relative dielectric constant; ε0 is the dielectric constant in vacuum; R is the solid state; T is the temperature; R s is the equivalent half-diameter; κ is the Debye-Hückel (Debye) parameter; F is the Faraday constant; ψ δ is the voltage on the starting surface of the diffusion layer.

[0167] When the ore particles collide with the bubbles during the cavitation reaction, the huge heat energy released by the fracture of the bubbles makes it impossible for the ore particles to remain fixed under the heat flow field, thus causing a dissociation process, that is, the originally embedded elemental sulfur is separated from the ore phase particles. Since the cavitation reaction involves the interaction between bubbles and ore particles of different sizes, the cavitation dissociation process includes flow field turbulence, photo-dissociation process, etc. Therefore, in order to more comprehensively explain the cavitation dissociation process, the photo-dissociation process of the ore particles should also be investigated preferentially.

[0168] The dissociation probability is used to handle the situation where the ore particles actually do not dissociate with the cavitation bubbles due to the streamline of the ore particles passing through the cavitation bubbles. The dissociation probability in the cavitation dissociation process is as follows:

[0169]

[0170] where p a is the dissociation probability in the cavitation dissociation process; Re b is the Reynolds number of the bubble; U b is the representative cavitation turbulence pulse velocity; t ind is the induction time, that is, the time required for the ore particles to reach stable attachment after contacting the bubbles; E dissociation (D) is the dissociation energy; d p is the particle diameter; d b is the bubble diameter; E collapse is the bubble collapse energy..

[0171] After determining the reaction control equation, the three-phase flow modeling of the cavitation dissociation process of elemental sulfur in high-sulfur slag is completed by using the finite volume method of FLUENT software. The simplified process of the modeling flow and implementation method is as follows:

[0172] (1) Suspend the solid phase in the solution, without considering precipitation and diffusion, and its velocity is the velocity of the phase where it is located;

[0173] (2) The cavitation bubbles cannot continue to collapse after collapse to dissociate the particles;

[0174] (3) Obtain the parameters determining the particle size and cavitation bubbles from the internal flow field, and use the solution of UDS to obtain the concentration parameters of the particles in two stages within the gas-liquid interface.

[0175] According to the above assumptions, the situation where the particle phase is in the control volume is shown in Figure 4 .

[0176] Based on the above-mentioned collision frequency simulation and dissociation probability model, during the cavitation reaction bubble collapse process and the high-sulfur slag particle dissociation process, the cavitation dissociation process of high-sulfur slag particles in the reactor was studied, and the concentration field was obtained. However, since the diffusion process in the cavitation dissociation process is slow compared to the gas convection process, the diffusion effect of mineral particles in the liquid was ignored in the modeling process. There are two states of high-sulfur slag in the reactor, namely: existing in the liquid or the cavitation bubbles existing in the gas phase are correspondingly suspended in the liquid or collide with the cavitation bubbles. Therefore, the concentration equations of particles are established separately for the gas phase and the liquid phase to describe the dissociation process of particles in the gas-liquid two-phase respectively. And the source term of the transport equation is added to the control volume to illustrate the transfer process of mutual trust between the two phases of particles at the gas-liquid interface during dissociation. The mineral phase dissociation equation at the gas-liquid interface is as follows:

[0177] Mineral phase dissociation equation at the gas interface:

[0178]

[0179] Mineral phase dissociation equation at the liquid interface:

[0180]

[0181] Among them, α is the two-phase volume fraction; n is the concentration of high-sulfur slag particles in the two phases; φ is the two-phase transfer source term.

[0182] The mineral phase dissociation equation at the gas-liquid interface directly quantifies the macroscopic dissociation rate through the product of the "collision frequency" and the "dissociation probability". The collision frequency simulation (such as the hydrodynamic model) calculates the dynamic collision times of mineral particles at the interface, reflecting the particle transport efficiency; the dissociation probability model (based on the interface energy or activation energy) calculates the probability of mineral dissociation in a single collision, reflecting the thermodynamic energy barrier of the interface reaction. The combination of the two realizes the cross-scale coupling of the kinetic process (particle motion) and the thermodynamic process (interface reaction), thus transforming the microscopic collision event into the core term of the macroscopic dissociation rate equation and finally embedding it into the mass and energy conservation equations to predict the mineral phase evolution.

[0183] Step 3: Define the boundary conditions, initial values of the model and the model grid division.

[0184] In this example, a degassing boundary is set for the gas outlet above the high-sulfur slag cavitation dissociation reactor. The gas volume fraction of the entire calculation area of the reactor is set to 0. It is considered that when the gas flow rate and mass flow rate at the gas inlet and gas outlet are equal, the model reaches a quasi-steady state, and the two-phase turbulent kinetic energy in the reactor remains basically unchanged. It is determined that the two-phase numerical model under this quasi-steady state can calculate the gas-liquid two-phase flow field in the high-sulfur slag cavitation dissociation reactor.

[0185] In this embodiment, the physical property parameters of the gas-liquid two-phase of the two-phase flow model are shown in Table 2.

[0186] Table 2 Physical properties of gas and liquid phases in two-phase flow model

[0187]

[0188] The boundary conditions and parameter initial values include: flow field boundary conditions and initial values, and reactor concentration field boundary conditions and initial values;

[0189] The initial values corresponding to the flow field include: gas phase inlet and outlet boundary positions, inflow velocity, outflow velocity, pressure and gravity conditions of the calculation domain in the cavitation dissociation reactor;

[0190] The initial values corresponding to the concentration field in the reactor include: initial overall regional substance concentration setting of the cavitation dissociation reactor;

[0191] The boundary conditions in different models are shown in Tables 3 and 4:

[0192] Table 3 Experimental conditions of cavitation dissociation experiment

[0193]

[0194] Table 4 Experimental conditions for cavitation dissociation experiments (continued)

[0195]

[0196] In this example, meshing was primarily based on finite element analysis of the physical field equations. For the model constructed in this study, ANSYS Fluent simulation software used the finite volume method (FVM) to mesh and solve the CFD model. A mesh independence test was performed to ensure that the calculation results were consistent with different mesh counts. The resulting Reactor A mesh had 19,358 grid cells. The resulting Reactor B mesh had 20,789 grid cells.

[0197] Step 4: After completing steps 1 to 3, perform CFD finite element simulation calculations to couple the gas phase and slag phase two-phase flow control equations, chemical reaction mass transfer and cavitation dissociation in the high-sulfur slag cavitation dissociation reactor to solve the flow field distribution characteristics, reaction material concentration distribution and cavitation dissociation efficiency results of the model; obtain the cavitation dissociation effect, gas-liquid two-phase velocity distribution, and gas phase distribution under the set operating parameters, as shown in the figure. Figures 5 - 10 As shown. The relationship between the reaction parameters and the gas-liquid two-phase flow field, gas-liquid two-phase velocity distribution, and gas phase distribution is as follows: Under the same gas flow, the smaller the total surface area of large bubbles, the faster the rising rate of bubbles, and the less favorable it is for the cavitation decomposition of fine particles. The smaller the bubbles, the easier they are to decompose. The lower the rising rate of bubbles, the more uniform the gas distribution and the greater the cavitation effect. The gas phase velocity in the reactor is much higher than the liquid phase velocity, and its internal field changes mainly depend on the liquid phase velocity. The higher the turbulence, the better the dissociation effect.

[0198] Step 5: Data analysis and further optimization of structure and parameters. When using the dissociation effect, gas-liquid two-phase velocity distribution, and gas-phase distribution as the basis for optimizing the reactor, the optimization strategy is as follows: If you want to improve the dissociation effect, gas distribution uniformity, and gas-liquid two-phase flow rate, then select an appropriate extension of the dissociation time, an appropriate reactor temperature, adjust the gas flow rate, and avoid too high a pulp concentration. In this embodiment, the preset value in the preset conditions satisfied by the cavitation dissociation effect is 95%, that is, the volume cumulative distribution rate of high-sulfur slag particles being greater than or equal to 95% satisfies the preset conditions.

[0199] In this embodiment, the results described in Step 4 are obtained based on the numerical simulation of the cavitation dissociation reactor using CFD technology. Each time, 5 g of ore sample and 40 mL of water are weighed and stirred for 2 min using a stirrer, and then enter the cavitation dissociation reactor from the slag mixing barrel through a feed pump. The gas used enters the cavitation dissociation reactor through a cavitator from a gas reservoir, and is adjusted using flow meters respectively. The material circulates internally through the main circulation pump. After the cavitation dissociation time reaches 4 min, all products are dried and weighed respectively. Some products are sent for particle size measurement, and some products are sieved and then subjected to phase analysis. Generally speaking, under this structure and operating parameters, there is a large gap between the reactor design with co-current gas-liquid flow and the reactor design with counter-current gas-liquid flow, which is mainly reflected in the intensity of the cavitation dissociation zone. At the same time, it is also manifested as a relatively low gas-phase volume fraction, uneven distribution of the normal velocities of the gas-liquid two-phase, and a low turbulence intensity distribution. All these lead to the difficulty of cavitation occurring in the laboratory-scale co-current gas-liquid reactor, and thus result in a low dissociation efficiency of high-sulfur slag. The design of the cavitation dissociation reactor with counter-current gas-liquid flow is relatively successful, and it can be considered that the conditions for cavitation are basically met, realizing the cavitation dissociation process of high-sulfur slag elemental sulfur, and still needing to carry out the next step of structure and operating parameter optimization.

[0200] Based on Steps 1 to 5, the reactor structure is optimized. Appropriately extend the dissociation time, set an appropriate reactor temperature, adjust the gas flow rate, and avoid too high a pulp concentration respectively. After performing the above steps, new simulation calculation results are obtained, as shown in Figures 11 - 17As shown, it can be found that in the cavitation dissociation reactor with an optimized structure, the particle size with the best dissociation effect during the cavitation dissociation process of high-sulfur slag is 100 μm, and the key factor affecting the particle dissociation effect is the gas-liquid-solid three-phase distribution; increasing the cavitation dissociation time in the reactor can promote the transformation of high-sulfur slag particles from the original wrapped form to the dissociated form. Under different dissociation time conditions, the gas-phase and liquid-phase distributions required for the cavitation dissociation of high-sulfur slag are different. Specifically, the longer the dissociation time, the higher the required gas-phase volume fraction and the higher the liquid-phase turbulence intensity; temperature is also a key factor affecting the cavitation dissociation of elemental sulfur in high-sulfur slag. Increasing the temperature in the reactor increases the maximum equivalent radius of the cavitation bubbles and prolongs the cavitation pulsation period. And due to the influence of the saturated vapor pressure, the energy of the cavitation bubbles reaches the maximum at a reactor temperature of 80 °C, and the dissociation effect is the best; the gas flow rate in the reactor is not the higher the better, and there is a critical value for the gas-phase volume fraction distribution. When exceeding this value, the tendency to generate cavitation bubbles will weaken; the pulp concentration is inversely proportional to the dissociation effect. The increase in pulp concentration will lead to an increase in the volume fraction of solid-phase particles in the reactor, resulting in a decrease in the dissociation effect of high-sulfur slag.

[0201] Example 2

[0202] The present invention provides an optimized system for a high-sulfur slag cavitation dissociation reactor, including:

[0203] Geometric model construction model: used to construct a geometric model of the fluid calculation domain of the high-sulfur slag cavitation dissociation reactor based on the basic structure size parameters of the high-sulfur slag cavitation dissociation reactor;

[0204] Reaction control equation determination module: used to determine the reaction control equation of the geometric model, and the reaction control equation is used to simulate the high-sulfur slag cavitation dissociation process in the reactor;

[0205] Parameter setting and simulation module: used to set the operating parameters of the geometric model and perform grid division on the geometric model; wherein, the operating parameters include the corresponding boundary conditions and parameter initial values; used to perform simulation calculation based on the geometric model after grid division to obtain the reaction parameters inside the high-sulfur slag cavitation dissociation reactor, and obtain the cavitation dissociation effect in the reactor as the optimization basis;

[0206] Model optimization module: based on the optimization basis, adjust the structural parameters and / or operating parameters of the reactor in the parameter setting and simulation module, and then perform simulation, and judge whether the optimization basis reaches the preset conditions. If not, continue to adjust the structural parameters and / or operating parameters of the reactor until the preset conditions are reached.

[0207] Example 3

[0208] The present invention provides an electronic terminal, including a processor and a memory. The memory stores a computer program, and the processor calls the computer program to execute the steps of the method described above.

[0209] Embodiment 4

[0210] The present invention provides a readable storage medium storing a computer program, and when the computer program is called by a processor, the steps of the method described above are executed.

[0211] It can be understood that the same or similar parts in the above embodiments can be referred to each other, and the content not described in detail in some embodiments can be referred to the same or similar content in other embodiments.

[0212] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0213] It should be understood that in the embodiments of the present invention, the so-called processor may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The memory may include a read-only memory and a random access memory, and provide instructions and data to the processor. A part of the memory may also include a non-volatile random access memory. For example, the memory may also store information about the device type.

[0214] The readable storage medium is a computer-readable storage medium, which may be an internal storage unit of the controller described in any of the foregoing embodiments, such as the hard disk or memory of the controller. The readable storage medium may also be an external storage device of the controller, such as a plug-in hard disk equipped on the controller, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, etc. Further, the readable storage medium may also include both the internal storage unit of the controller and the external storage device. The readable storage medium is used to store the computer program and other programs and data required by the controller. The readable storage medium may also be used to temporarily store data that has been output or is to be output.

[0215] Based on such an understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, may be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The foregoing readable storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disc.

Claims

1. An optimization method for a high-sulfur slag air dissociation reactor, characterized in that Including: S1: Based on the basic structural dimension parameters of the high-sulfur slag thermal dissociation reactor, construct a geometric model of the fluid calculation domain of the high-sulfur slag thermal dissociation reactor; S2: Determine the reaction control equations of the geometric model, which are used to simulate the high-sulfur slag thermal dissociation process in the reactor; S3: Set the operating parameters of the geometric model and perform grid division on the geometric model; wherein, the operating parameters include the corresponding boundary conditions and parameter initial values; S4: Perform simulation calculation based on the geometric model after grid division to obtain the reaction parameters inside the high-sulfur slag thermal dissociation reactor, and obtain the thermal dissociation effect inside the reactor based on the reaction parameters as the optimization basis; S5: Adjust the structural parameters and / or operating parameters of the reactor based on the optimization basis, then perform simulation in the aforementioned manner, and judge whether the optimization basis reaches the preset conditions. If not, continue to adjust the structural parameters and / or operating parameters of the reactor until the preset conditions are reached.

2. The optimized method for the high-sulfur slag air dissociation reactor according to claim 1, characterized in that The reaction control equations in S2 include: Material flux vector equation in the high-sulfur slag thermal dissociation reactor: Where, i refers to substance i in the high-sulfur slag air dissociation reactor; N i is the substance flux vector in the high-sulfur slag air dissociation reactor; D i is the diffusion coefficient of substances in the high-sulfur slag air dissociation reactor; c i is the concentration of substances in the high-sulfur slag air dissociation reactor; is the sum of the first-order partial derivatives of the substance concentration c i in three directions; u is the fluid velocity vector of substances in the high-sulfur slag air dissociation reactor; Material balance control equation: In the formula, is the Laplace operator; R i represents the reaction rate of the substance; The continuity equation is: Among them, a q is the volume fraction of the q-phase; ρ q is the density of the q-phase; is the flow velocity of the q-phase; is the mass transfer from the p-phase to the q-phase; is the mass transfer from the q-phase to the p-phase; S q is the mass source term of the q-phase; n is the number of terms; The momentum equation is: where τ q is the q-corresponding stress-strain tensor; is the gravitational acceleration; is the interphase exchange coefficient; are all the interphase velocities; is the body force; is the lift force; is the wall lubrication force; is the virtual mass force; is the turbulent dispersion force; The energy equation is: where h q is the specific enthalpy of phase q; is the shear viscosity of phase q; is the heat flux of phase q; Q pq is the heat exchange rate between phases p and q; is the mass transfer from phase p to phase q; is the mass transfer from phase q to phase p; h pq is the specific enthalpy difference between phases p and q; h qp is the specific enthalpy difference between phases q and p.

3. The optimization method of the high-sulfur slag air dissociation reactor according to claim 2, wherein The calculation formula for the virtual mass force is: Among them, is the virtual mass force; C VM is the virtual mass force model constant; a l is the liquid volume fraction; ρ g is the gas density; is the gas velocity; is the liquid velocity; D / D t is the substantial derivative of the two-phase; The calculation formula for the lift force is: Among them, is the lift force; a g is the gas volume fraction; ρ l is the liquid phase density; C L is the lift force model constant; is the gas phase flow velocity; is the liquid phase flow velocity; The calculation formula for the drag force is: Among them, F D,l is the liquid-phase drag force; F D,g is the gas-phase drag force; ρ l is the liquid-phase density; a g is the gas-phase volume fraction; a l is the liquid-phase volume fraction; C D is the drag coefficient; d b is the bubble diameter; is the gas-phase flow velocity; is the liquid-phase flow velocity.

4. The optimization method of the high-sulfur slag air dissociation reactor according to claim 1, characterized in that, The thermal dissociation reactor adopts a round orifice jet, and the Standard k-ε model is selected as the turbulence model. The transport equation of the Standard k-ε model is: where ρ is the fluid density; k is the turbulent kinetic energy; u i is the component of the fluid velocity in the i direction; x i is the component of the spatial coordinate in the i direction; x j is the component of the spatial coordinate in the j direction; μ is the viscosity; μ t is the turbulent viscosity; σ k is the turbulent Prandtl number of the turbulent kinetic energy; G k is the turbulent kinetic energy caused by the mean velocity gradient; G b is the turbulent kinetic energy generated by buoyancy; ε is the turbulent energy dissipation rate; Y M is the contribution of the fluctuating expansion of the compressible turbulence to the total dissipation rate; S k is the source term; Turbulent viscosity μ T It can be expressed as: Among them, ρ is the fluid density; k is the turbulent kinetic energy; ε is the turbulent energy dissipation rate; among them, k and ε satisfy: where the derivative term P k satisfies: Among them, C μ , σ k , σ ε , C ε1 , C ε2 , and C ε are all model parameters.

5. The optimization method of the high-sulfur slag air dissociation reactor according to claim 1, characterized in that The mineral phase dissociation equation at the gas-liquid interface is specifically as follows: Mineral phase dissociation equation at the gas interface: Mineral phase dissociation equation at the liquid interface: Among them, α is the two-phase volume fraction, n is the two-phase high-sulfur slag particle concentration, and φ is the two-phase transfer source term.

6. The optimized method for the high-sulfur slag air dissociation reactor according to claim 5, wherein The collision frequency model during the thermal dissociation process is: r collision = z pb n l n g where r collision is the collision frequency; n l is the particle concentration; n g is the cavitation bubble concentration; z pb is the collision frequency coefficient between particles and bubbles; d p is the particle diameter; d b is the bubble diameter; U p is the particle turbulent pulsation velocity; U b represents the cavitation bubble turbulent pulsation velocity.

7. The optimization method of the high-sulfur slag air dissociation reactor according to claim 5, characterized in that The dissociation energy between the gas phase and the liquid phase is: Among them, E dissociation is the dissociation energy; D is the effective distance between the two surfaces; ε is the relative dielectric constant; ε0 is the permittivity in vacuum; R is the solid state; T is the temperature; R s is the equivalent zero-point five radius; κ is the Debye-Hückel parameter; F is the Faraday constant; ψ δ is the voltage at the start surface of the diffusion layer.

8. The optimized method for the high-sulfur slag air dissociation reactor according to claim 5, wherein The dissociation probability during the thermal dissociation process is: Among them, p a is the dissociation probability during the cavitation dissociation process; Re b is the Reynolds number of the bubble; U b represents the cavitation turbulence pulse flow velocity; t ind is the induction time, that is, the time required for the ore particle to reach stable attachment after contacting the bubble; E dissociation (D) is the dissociation energy; d p is the particle diameter; d b is the bubble diameter; E collapse is the bubble collapse energy.

9. The optimization method of the high-sulfur slag air dissociation reactor according to claim 1, wherein The boundary conditions and parameter initial values in S3 include: flow field boundary conditions and initial values, boundary conditions and initial values of the concentration field inside the reactor; The initial values corresponding to the flow field include: gas phase inlet and outlet boundary positions, inflow velocity, outflow velocity, pressure and gravity conditions in the calculation domain of the thermal dissociation reactor; The initial values corresponding to the concentration field inside the reactor include: the initial overall area material concentration of the thermal dissociation reactor.

10. The optimized method for the high-sulfur slag air dissociation reactor according to claim 1, wherein The preset conditions reached by the optimization basis in S5 are specifically: The thermal dissociation effect is judged by whether the volume accumulation distribution rate of the high-sulfur slag particles is greater than or equal to the preset value: if so, it indicates that the preset conditions are met; if not, it indicates that the preset conditions are not met.

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