2864 results about "High concentration" patented technology

The invention provides a solar interface evaporator based on amphoteric polyelectrolyte photo-thermal hydrogel, a preparation method and application, and belongs to the field of solar interface evaporation. The solar interface evaporator with a three-dimensional multi-surface evaporation structure is prepared by combining the polyelectrolyte resisting effect of the amphoteric polyelectrolyte photo-thermal hydrogel and the porous capillary effect of the sponge, and has the characteristics of high light absorptivity, good water absorption effect, excellent antibacterial property, mechanical property, salt resistance, evaporation property and the like; particularly, compared with a traditional hydrogel-based solar interface evaporator, the water delivery capacity and the salt resistance in high-concentration saline water are greatly improved through the application of the autonomously designed zwitterionic hydrogel, water molecules in the saline water are activated through the cooperation of salt-resistant ionized water, the evaporation enthalpy is reduced, and the evaporation efficiency is improved. And a great positive effect is achieved on improvement of the evaporation rate. The evaporator is easy to prepare and excellent in multi-dimensional performance, and a new way and thought are provided for application to seawater desalination and wastewater treatment.

The invention discloses a cyanamide axial coordination cobalt monatomic catalyst for persulfate activation and a preparation method and application thereof, and belongs to the technical field of persulfate advanced oxidation. The catalyst is prepared by the following method: simultaneously adding NH2CN and NaOH into a CoCl2 solution, stirring for reaction, and after the reaction is finished, washing, filtering and drying to obtain the catalyst CoN4 (NCN). The catalyst CoN4 (NCN) with an isolated Co site and cyanamide ([NCN] 2-) coordination structure is synthesized by adopting a one-step precipitation method. The catalyst can be used for an advanced oxidation system based on persulfate activation, and can be used for deeply treating a water body polluted by high-concentration organic matters, so that the biodegradability of the water body is improved. In addition, CoN4 (NCN) also has obvious stability and environmental adaptability, and has important application prospect and value in the field of organic pollutant degradation.

The invention provides a method for selecting a high-concentration VOCs adsorbent at different temperatures and application, and belongs to the technical field of waste gas governing. According to the method, through testing pore structure parameters of a model adsorption material with concentrated pore size distribution, a static adsorption isotherm and a dynamic penetration curve for VOCs at different temperatures, a high-concentration VOCs adsorbent is obtained; a linear relation equation of the critical aperture and the critical pressure is established through linear fitting, then a correlation equation of the critical aperture, the temperature and the partial pressure is established, and the appropriate aperture distribution range and the model selection standard of the high-concentration VOCs adsorbent at different temperatures are determined by combining dynamic adsorption results. According to the method, the ternary matching relation equation of the VOCs partial pressure, the temperature and the critical aperture is constructed, accurate type selection of the high-concentration VOCs adsorbent at different temperatures is achieved, the pore volume utilization rate and the adsorption capacity can be improved, meanwhile, desorption energy consumption and the VOCs pyrolysis risk are reduced, and a theoretical basis is provided for adsorbent type selection and technical optimization.

The invention relates to the field of water quality detection, in particular to a method, system and equipment for detecting solution impurities through a water quality detector and a medium. The method comprises the following steps: acquiring spectral data of a to-be-detected ion solution; a correction observation window is constructed on the spectral data according to the local concentration gradient and used for extracting local nonlinear features, and the local nonlinear features comprise absorbance gradient change features and fitting residual error anomaly features; establishing a mapping relation between the spectral data and a water quality detection result according to the local nonlinear characteristics in the correction observation window, and generating a correction coefficient through a scatter correction algorithm; correcting the spectral data according to the mapping relation and the correction coefficient; and identifying impurity components in the ion solution based on the corrected spectral data. The stable mapping relation between the absorbance and the impurity concentration can still be maintained in a strong ion interference environment, so that the measurement result can keep reliable precision even in a high-concentration ion intensity environment.

The invention relates to the technical field of exosome loaded drugs, and provides a preparation method and application of exosome vesicles capable of efficiently loading drugs, and the preparation method comprises the following steps: exosome preparation: preparing an exosome sample with enough granularity and purity; pretreatment of exosomes: performing precipitation treatment and collecting the exosomes to prepare exosome precipitates; carrying out loaded medicine pretreatment: treating loaded medicine or a medicine preparation by using a lipid reagent; target drug loading: rapidly treating the exosome precipitate by using a drug lipid component, and then treating by using a buffer system to obtain the exosome load of the drug; and free lipid and drug removal: reducing free lipid and drug residues by re-enriching the exosomes. The problems of high concentration, high purity and low cost in industrial production of the exosome are solved, meanwhile, an efficient and convenient technical method is provided for taking the exosome loaded medicine as a delivery system, and the method can be suitable for the fields of health medical treatment, medical beauty cosmetics and biological medicine products.

The invention belongs to the technical field of back contact photovoltaic cells, and particularly relates to a back contact photovoltaic cell with high-concentration co-doped regions and a manufacturing method and application thereof.The back contact photovoltaic cell with the high-concentration co-doped regions is characterized in that N-type doped regions and P-type doped regions which are alternately distributed are arranged on the backlight face of an intrinsic amorphous silicon layer, and the high-concentration co-doped regions are arranged between the N-type doped regions and the P-type doped regions; a doping source of the co-doped region comprises doping source phosphorus of the N-type doped region and doping source boron of the P-type doped region, the co-doped region, the doping source of the N-type doped region and the doping source of the P-type doped region form a specific concentration gradient structure, and the specific concentration gradient structure meets the condition that the doping concentration of phosphorus contained in the co-doped region is greater than that of phosphorus contained in the N-type doped region; the doping concentration of boron contained in the co-doped region is greater than the doping concentration of boron in the P-type doped region. The carrier transport and collection efficiency is optimized, the fill factor and open-circuit voltage are improved, the cell conversion efficiency and stability are improved, the preparation process is simple, and multiple times of opening etching are not needed.

The invention discloses a method, a device, equipment and a medium for simulating migration of a proppant, and relates to the technical field of analogue simulation. Simulation is carried out through fluid dynamics and a discrete element analysis model, specifically, fluid parameters are obtained, a calculation model is constructed, and constraints are set; parameters are input for fluid and particle stress analysis, and particle displacement and grid updating are calculated; contact is judged through the particle collision sequence, boundary force is calculated, and the particle motion state is updated; and cyclically feeding back the flow field parameters to particle stress analysis until the number of iterations is met so as to obtain the void ratio, the flow velocity, the position and the momentum of the particles. According to the invention, the motion among particles can be captured and accurately calculated in a high-concentration particle flow or particle dominated collision system.

The invention relates to the technical field of laser particle size analyzers, in particular to a laser particle size analyzer with a double-ultrasonic structure, which comprises a particle size analyzer body, a sample pool is arranged on the particle size analyzer body, a sample dispersion mechanism for crushing particle blocks is arranged in the sample pool, and a stirring auxiliary mechanism for preventing suspended particles from settling is arranged above the sample pool. The stirring auxiliary mechanism can push the particles to a sound field strong area of the sample dispersion mechanism so as to improve the dispersion efficiency, and a splash-proof covering mechanism is arranged at the upper end of the sample pool. By arranging the sample dispersion mechanism and adopting a mode of combining phase orthogonality and material orthogonality layout, a stable three-dimensional acoustic vortex can be formed in the sample pool, and the coverage range of the ultrasonic cavitation effect can be obviously improved, so that the particle dispersion uniformity is improved, and the particle dispersion efficiency is improved. A detachable low-frequency ultrasonic vibrator is adopted at the bottom, so that the penetrating power of a high-concentration and high-viscosity sample is further enhanced, and dispersion dead angles can be effectively eliminated.

The invention is suitable for the technical field of inorganic luminescent materials, and provides a fluorescent powder material based on a double-perovskite structure and a preparation method and application thereof. The general chemical formula of the fluorescent powder is Ca2AlNbO6: xEu < 3 + >, wherein x is a molar fraction of 0.06 to 0.30; the excitation spectrum coverage range of the fluorescent powder under the condition of monitoring the emission wavelength of 615 nm is 260-500 nm, and the emission main peak is located at 615 nm; when x is equal to 0.18, the quantum efficiency under the excitation of 396nm ultraviolet light is greater than or equal to 91%, and the red light emission ratio is greater than or equal to 85%. According to the invention, Ca2AlNbO6 double perovskite is taken as a substrate, and a red fluorescent powder material with wide-spectrum excitation and high quantum efficiency is designed through Eu < 3 + > high-concentration doping and local symmetry regulation and control design engineering, so that the characteristics of high quantum efficiency, efficient red light emission, wide-spectrum excitation and excellent concentration quenching resistance are realized.

The invention relates to the technical field of high-concentration chemical wastewater treatment of explosives and powders, and particularly discloses anti-blocking treatment equipment for high-concentration chemical wastewater treatment of explosives and powders. One end of a filter pipe is fixedly connected with a water inlet pipe, and the other end of the filter pipe is fixedly connected with a water outlet pipe; the ends, away from the filter pipe, of the water inlet pipe and the water outlet pipe are fixedly connected with net plates. The anti-blocking treatment equipment for treating high-concentration chemical wastewater of explosives and powders is provided with an intercepting part, and when a baffle intercepts impurities for a long time to cause blockage of meshes, the impact force of wastewater passing through the baffle is weakened and is smaller than the tensile force of a first spring, the first spring pulls a connecting frame to move towards the baffle; the connecting frame drives the ejector rod to penetrate into the meshes of the baffle through the sliding rod, impurities blocked in the meshes are ejected out, the filtering function of the baffle is recovered, quick response can be achieved in the early stage of blocking, the problems of treatment efficiency reduction, unsmooth water flow, even equipment failure and the like caused by impurity accumulation are solved, and the anti-blocking performance of equipment is improved.

The invention provides particles, compositions including the particles, and methods of making the particles using electrospray. In certain embodiments, the particles allow for high concentrations of a therapeutic or diagnostic agent to be delivered at low viscosity. Particles may also exhibit beneficial properties with respect to stability.

The invention discloses a coal mine safety production monitoring method and system based on video images, and relates to the technical field of computer vision and mine safety monitoring, and the method comprises the following steps which are executed in sequence: (a) collecting a real-time video stream of an underground monitoring area; (b) establishing a light-dust coupling degradation model based on video frames in a real-time video stream, and decomposing an image into an illumination substrate layer, a dynamic dust layer and a target feature layer; according to the coal mine safety production monitoring method and system based on the video image, accurate separation of interference sources is achieved by establishing a light-dust coupling degradation physical model, target essential features are reconstructed in combination with a dual-channel dynamic enhancement mechanism, and the problem of micro-feature annihilation caused by coupling of underground complex illumination fluctuation and high-concentration dust is fundamentally solved.

The invention relates to the technical field of conductive materials, in particular to a high-concentration dispersion system and a preparation method thereof. The high-concentration dispersion system comprises a conductive agent, a dispersing agent, a solvent and a viscosity reduction auxiliary agent, the conductive agent is modified carbon nanotubes, the dispersing agent is modified polyvinylpyrrolidone, the solvent is N-methyl pyrrolidone or deionized water, and the viscosity reduction auxiliary agent is piperazine anhydrous; wherein the modified carbon nano tube is obtained by mixing and heating a carbon nano tube and a mixed acid solution of nitric acid and sulfuric acid, then cooling, filtering, washing, drying, then dispersing in 75% ethanol, and finally adding 3-[3-carboxyl allylamido] propyltriethoxysilane for modification; the modified polyvinylpyrrolidone is obtained by heating polyvinylpyrrolidone at 310-330 DEG C and then oxidizing the polyvinylpyrrolidone. The conductive agent content of the high-concentration dispersion system is high, the conductive agent accounts for 15%-20% of the high-concentration dispersion system by mass, and the high-concentration dispersion system is low in viscosity, high in dispersity and good in conductivity.

The invention relates to the technical field of image data processing, in particular to a water-soluble fertilizer dissolution rate visual measurement method and system, and the method comprises the steps: obtaining a sequence image of a dissolution process; performing multi-scale frequency domain analysis on the image, and calculating a scale convergence index by using the deviation between a local phase and a weighted average phase; a spectral sharpness factor is calculated according to the ratio of the high-frequency energy response to the low-frequency energy response; fusing the scale convergence index and the spectral sharpness factor to obtain a solid boundary probability; segmenting the particle region based on the probability and converting the particle region into physical mass, and differentiating a mass change sequence to obtain a dissolution rate. By fusing the phase consistency and the frequency domain energy distribution characteristics, the physical entity edge and the optical refraction halo are effectively distinguished, the refraction interference problem during high-concentration dissolution is solved, and the dissolution rate measurement accuracy is improved.

The invention relates to an electrochemical cleaning method for removing organic matters on the surface of a silicon carbide wafer, which comprises the following steps of: immersing the silicon carbide wafer with the polluted surface into electrolyte containing bivalent and / or trivalent ferric salt, applying voltage or current between a cathode material and an anode material, and carrying out electrochemical reaction to remove the organic matters on the surface of the silicon carbide wafer. The surface of the silicon carbide wafer is subjected to organic matter removal. According to the method, an electrochemical oxidation method technology is adopted, the strong oxidation effect of hydroxyl free radicals is utilized, organic residues on the surface of the silicon carbide wafer are oxidized and decomposed into short-chain organic matter, water, carbon dioxide and other products, and the purpose of removing the organic residues is achieved. The method provided by the invention is simple and efficient, can quickly remove organic pollutant residues on the surface of the silicon carbide wafer, does not use high-concentration chemicals and organic component cleaning agents which are difficult to degrade in the cleaning process, is safe and reliable to operate, reduces the consumption of the chemicals, avoids secondary pollution, and is more environment-friendly.

The invention discloses a tracing method and system for atmospheric pollution in a chemical industry park, and relates to the technical field of tracing of atmospheric pollution. The method comprises the following steps: determining at least one first pollution source according to an enterprise-pollutant-raw material incidence matrix and at least one pollutant in the chemical industry park; and according to the real-time pollutant concentration data and a Gaussian diffusion model simulation result, screening out an enterprise with a relatively high fitting degree with the real-time pollutant concentration data, and according to a screening result, determining at least one second pollution source. And determining at least one third pollution source according to the position of the at least one pollution source. And determining at least one fourth pollution source in the high-concentration change area. And determining a pollution traceability result. According to the invention, multi-source data are fused to trace the air pollution, the comprehensiveness and timeliness of the data are ensured, and the accuracy of pollution traceability can be improved.

The invention discloses a temperature control method for low-temperature high-NOx-concentration flue gas denitration in the nuclear industry, and relates to the technical field of flue gas denitration control. According to the method, flue gas temperature time sequence distribution, NOx concentration gradient and environment radiation intensity data are integrated through a space-time alignment algorithm, a synchronous data matrix representing a system coupling state is generated, then a temperature and efficiency response curved surface is established, a high-efficiency temperature area and an inactivation risk area are dynamically divided through fuzzy logic control, and an optimal temperature regulation and control threshold value is recognized. The drift effect of quantitative radiation on the surface temperature of the catalyst is analyzed through regression, a quantitative relation model of radiation dose and temperature zone deviation is established, and real-time correction of anti-radiation compensation parameters is achieved. And finally, optimizing the multi-objective cost function by adopting a non-dominated sorting genetic algorithm, and obtaining dynamic balance between the maximum NOx conversion rate and the minimum temperature fluctuation. And multi-parameter coupling control of a temperature field and a radiation field is realized, and the denitration efficiency stability under a low-temperature condition is remarkably improved.

The invention provides particles, compositions including the particles, and methods of making the particles using electrospray. In certain embodiments, the particles allow for high concentrations of a therapeutic or diagnostic agent to be delivered at low viscosity. Particles may also exhibit beneficial properties with respect to stability.

The invention relates to a rapid VOCs source component spectrum construction and evaluation method. The method comprises the following steps of S1, performing field investigation and survey to determine a target VOCs emission source, a sampling port position and a sampling mode; s2, carrying out on-site collection on a target VOCs source sample by utilizing an air bag or a Suma tank; s3, the sample is sent to a vehicle-mounted VOCs online analysis laboratory staying near a sampling source within 1-2 hours after being collected, and analysis and determination are conducted through an analysis instrument; and S4, based on the measured data of the plurality of VOCs samples of the same type of emission sources, constructing and evaluating the VOCs source component spectrum of the source type. According to the present invention, the on-site sampling and analysis determination method is adopted, the rationality of the on-site sampling method and the dilution scheme of the high concentration VOCs source sample are improved so as to achieve the detection range of the analysis instrument, and the timeliness and the accuracy of the obtained data are improved.

The utility model belongs to the field of wastewater treatment, in particular relates to a multi-stage evaporation and concentration device for high-concentration wastewater, and aims to solve the problems that the normal operation and efficiency are influenced due to the fact that existing crystals are deposited at the bottom of an evaporator along with the flowing of the wastewater. In order to solve the problems that in the prior art, during cleaning, manual cleaning is needed, the efficiency is low, each tank body needs to be cleaned independently, and automatic operation is difficult to achieve to improve the efficiency, according to the scheme, the evaporation device comprises a plurality of evaporation tanks, feeding ends are arranged at the tops of the evaporation tanks, and discharging ends are arranged at the bottoms of the evaporation tanks; an air inlet end is arranged on one side of the outer wall of the evaporation tank, an air outlet end is arranged on the other side of the outer wall of the evaporation tank, when crystals on the inner wall of the evaporation tank need to be cleaned, only water needs to be injected into the evaporation tank indirectly, the crystals can be scraped and discharged together with water through the cleaning assembly, and therefore automatic cleaning is achieved.

Disclosed herein are methods and systems for identifying target analytes such as H2S and CO2 during downhole fluid analysis. The systems may include a fluid sampling tool comprising at least one probe to fluidly connect the fluid sampling tool to a formation in a wellbore, at least one passageway that passes through the at least one probe and into the fluid sampling tool, a sensor section comprising a measurement region in fluid communication with the at least one passageway, and a thin film deposited on the measurement region, wherein the thin film changes at least one of its physical properties upon exposure to the target analyte found in the at least one passageway. The methods may include disposing the fluid sampling tool into a wellbore, drawing a formation fluid from a sampling zone, and passing the fluid sample over the thin film deposited on a measurement region.

The invention discloses a molecular film type automotive nitrogen and oxygen separation device which comprises a turbocharger, a nitrogen and oxygen separator, a gas inlet valve, a gas outlet valve, a negative pressure pump and an electric control throttling valve. The turbocharger is driven by a turbine in an automobile turbocharger, so that the air is compressed to be conveyed to two paths of the nitrogen and oxygen separation device, the nitrogen and oxygen separation device can separate oxygen from the air, the air with high oxygen content is output, and the air is supplied to an engine for use through the gas outlet valve. The two paths of the nitrogen and oxygen separation device work alternately, when the temperature of the two paths of the nitrogen and oxygen separation device is too high to influence oxygen production efficiency, a main air inlet pipeline is opened to provide air normally by controlling the opening degree of the electric control throttling valve, and thus the phenomena of gas circuit plugging and engine stalling are avoided. According to the automotive nitrogen and oxygen separation device, the two branch paths work alternately, high concentration oxygen can be supplied to the engine continuously so that fuel can burn and act, and the burning utilization rate of the fuel is improved.

The invention relates to the technical field of fluorescent probes, and provides a low-concentration ratio type high-concentration enhanced fluorescent probe as well as a preparation method and application thereof in order to solve the problems that a traditional fluorescent probe depends on a high-concentration use condition and is often faced with fast probe consumption, increased biotoxicity, non-specific target binding and the like in a biological sample. The preparation method of the fluorescent probe comprises the following steps: step 1, preparing phenothiazine dialdehyde; and 2, mixing phenothiazine dialdehyde, malononitrile, ethanol, acetonitrile, DMF and piperidine, and carrying out a reflux reaction to obtain the low-concentration ratio-type high-concentration enhanced fluorescent probe. The probe provided by the invention realizes quantitative detection of HClO through synchronous change of two emission channels, and the detection sensitivity and reliability are remarkably improved; when the concentration is high, an enhanced single-channel fluorescence amplification effect is shown, and strong signal identification and macroscopic visual imaging in specific application are facilitated, so that the dual requirements of trace monitoring and high-throughput screening are met.

The present invention relates to devices and systems for generating nanobubbles. The present invention also relates to methods of generating nanobubbles. The devices, systems and methods of present invention generate nanobubbles by employing one or more mechanism such as cavitation hydrodynamics, shearing force mechanism, baffle jet system and membrane-based diffusion. The devices, systems and methods of present invention produce uniformly sized nanobubbles and find applications in preparing stable nanobubble-infused beverages with high concentration of nanobubbles.

The invention discloses a multi-network anti-freezing hydrogel electrolyte, a preparation method thereof and application of the multi-network anti-freezing hydrogel electrolyte in an electrochemical device. The hydrogel is prepared by using polyvinyl alcohol (PVA) and polyacrylamide (PAM) to form a basic network skeleton, introducing phytic acid, ethylene glycol and lithium / zinc bimetal salt (Li2SO4 / ZnSO4), and carrying out thermal initiation polymerization and freeze thawing. The hydrogel prepared by the invention has a multiple physical cross-linked network formed by polymer molecular chain entanglement, hydrogen-bond interaction among functional groups and metal coordinate bonds constructed between phosphate groups and divalent metal ions, so that the hydrogel electrolyte has excellent mechanical properties. Due to introduction of ethylene glycol, formation of ice crystals is effectively inhibited, and the hydrogel is endowed with excellent anti-freezing performance; the high-concentration Li < + > and Zn < 2 + > ensure the high ionic conductivity. The supercapacitor assembled by using the hydrogel electrolyte shows relatively high specific capacitance and good capacitance retention rate under bending and freezing conditions, and has good electrochemical properties and safety performance.

The invention discloses a method for detecting the concentration of vanadium ions in an electrolyte of an all-vanadium redox flow battery, and relates to the technical field of batteries. The method for detecting the concentration of vanadium ions in the electrolyte of the all-vanadium redox flow battery comprises the following steps: preparing trivalent and tetravalent vanadium ion reference solutions and trivalent and tetravalent vanadium ion standard solutions with different concentrations; performing baseline correction by using a high-concentration reference solution, setting an absorbance difference value between a corresponding reference cell and a sample cell as 0, and obtaining a trivalent vanadium ion standard curve and a tetravalent vanadium ion standard curve by using standard solutions with different concentration gradients; and detecting the absorbance difference value of the electrolyte stock solution to be detected, and substituting the absorbance difference value into the corresponding standard curve to calculate the vanadium ion concentration. According to the present invention, the detection can be performed without diluting the electrolyte stock solution during the detection, the interference of the adjacent valence vanadium ions is not easily generated, and the detection result is accurate.

The invention belongs to the technical field of assisted reproduction, and particularly relates to a device and a method for gradually adjusting the glucose concentration of an in-vitro embryo culture solution. The device comprises at least two miniature liquid storage bins, wherein each miniature liquid storage bin is filled with a high-concentration glucose solution in advance; the slow release channel is respectively connected with each micro liquid storage bin and the culture solution main container; the culture solution main container is used for accommodating an embryo and a basal culture medium; the control unit is used for sequentially opening the release ports of the miniature liquid storage bins, so that the high-concentration glucose solution sequentially flows into the culture solution main container through the slow release channels. The technical means of staged closed-loop micro sugar control is introduced into the structure and the using method of the device, so that the accurate adjustment of the sugar concentration of the in-vitro embryo culture solution is realized, the requirements of embryos in different development stages can be effectively met, and the embryo culture quality and the subsequent development potential are remarkably improved.

The invention relates to a P-type GaN LED epitaxial structure based on segmented annealing and compensation doping and a preparation method thereof, and belongs to the technical field of nitride semiconductor epitaxial growth and doping activation. The epitaxial structure sequentially comprises a buffer layer, a non-doped GaN layer, an N-type GaN layer, a multi-quantum well active layer, a P-type AlGaN electron barrier layer, a P-type GaN layer and an MgN compensation layer which are arranged on the substrate layer; wherein the MgN compensation layer is a high-concentration magnesium-doped nitride semiconductor layer, is arranged on the P-type GaN layer, and is used for compensating Mg loss and inhibiting nitrogen vacancy formation in the subsequent annealing process. The preparation method comprises the steps of performing multi-stage annealing treatment on the P-type GaN layer, performing epitaxial growth and annealing on the compensation layer, and finally performing low-temperature post-treatment annealing to form a surface passivation region. According to the structure, the Mg activation efficiency and the hole concentration are remarkably improved through an in-vivo activation and surface compensation synergistic mechanism, the contact resistance is reduced, the conductivity and the light-emitting performance of an LED device are improved, and the structure has excellent implementability and industrialization prospects.

The present invention discloses a production method for reducing slag grooves during the casting process of spring steel billets, specifically: the superheat degree of the continuous casting molten steel is between 20 and 40°C, slag is automatically added to the continuous casting billet, and the protective slag is transported to the crystallizer through compressed air as a carrier, thereby ensuring a relatively high concentration of compressed air atmosphere at the upper mouth of the crystallizer, which has a combustion-supporting effect on the protective slag, thereby improving the melting effect of the protective slag. The insertion depth of the submerged nozzle is 70‑80mm, which ensures a relatively high temperature of the molten steel on the meniscus of the crystallizer, thereby improving the melting effect of the slag surface. The slag line remains unchanged during the casting process; the crystallizer uses high-frequency and high-amplitude vibration parameters to increase the negative slip time and the crystallizer vibration advance, which is beneficial to the inflow of liquid protective slag into the air gap between the billet and the copper tube, thereby avoiding the slag groove phenomenon during the billet casting process.

The embodiment of the invention discloses a fluorine removal agent and a fluorine removal process for rare earth feed liquid. The fluorine removal agent comprises a first fluorine removal agent and a second fluorine removal agent, the first fluorine removal agent is polycrystal system composite calcium, the polycrystal system composite calcium is composed of calcium oxide / calcium hydroxide and calcium carbonate according to the mass ratio of (0.1-1): (0.1-1), and the second fluorine removal agent is composed of polycrystal system composite calcium and an inorganic flocculant according to the mass ratio of (0.01-1): (0.01-1). According to the method, fluorine is removed under the condition that the pH value is 4.6-5.8, fluoride composite salt precipitation is formed, fluorine in the rare earth solution can be efficiently removed, rare earth carbonate precipitated from subsequent oxalic acid or carbonate (sodium carbonate, sodium bicarbonate, ammonium bicarbonate and the like) or high-concentration rare earth feed liquid can be recycled, and the quality of the rare earth is improved. The requirements (the F content in the mixed rare earth oxide is less than 0.3%, and the F content in the high-concentration rare earth feed liquid (the concentration is greater than 100g / L) is less than 100mg / L) are met. The method is simple in process and high in operability, and has a relatively good application prospect.