35 results about "High magnesium" patented technology

The purpose of the present disclosure is to provide magnesium glycinate which has a high magnesium concentration.　Disclosed is magnesium glycinate which is configured such that, in differential scanning calorimetry analysis, the value S1 / S2 obtained by dividing the area S1 of an endothermic peak that has a starting temperature in the range of 230°C to 255°C by the area S2 of an endothermic peak that has a starting temperature in the range of 330°C to 370°C is 0 to 7 inclusive.

The invention discloses a vanadium inhibitor and a preparation method thereof, a petroleum additive and application, and the vanadium inhibitor comprises the following components in percentage by mass: 45%-70% of a magnesium-containing compound, 5%-22% of a dispersing agent, 15%-45% of a solvent and 0.5%-8% of an anti-settling agent. Wherein the mass percent of the magnesium element in the vanadium inhibitor is 20%-36%, the particle size D100 of the vanadium inhibitor is smaller than 350 nm, and the magnesium-containing compound comprises one or more of magnesium oxide, magnesium hydroxide and magnesium carbonate. The vanadium inhibitor with high magnesium element content and small particle size range is obtained by selecting the specific magnesium-containing compound and optimizing the formula of the vanadium inhibitor, can be efficiently combined with the vanadium element in an oil material to generate magnesium vanadate, has a good vanadium inhibition effect, still keeps excellent flowability in a water-containing environment or high and low-temperature environments, and can be used for preparing magnesium vanadate. Decomposition and curing do not occur, and good stability is achieved.

The present invention belongs to the technical field of glass fibers, and specifically relates to a high-magnesium, high-specific modulus glass fiber composition and glass fibers. The mass percentages of the components are SiO2: 58.5-63.0%, Al2O3: 15.0-20.0%, CaO: 0.3-2.5%, MgO: 16.0-19.5%, Fe2O3: 0.2-0.6%, Y2O3+B2O3: 1.0-3.5%, B2O3: 0.1-1.0%, and K2O+Na2O: 0.3-0.8%. The present invention significantly increases the MgO content, increases the SiO2 content, reduces the Al2O3 and CaO contents, and adjusts the usage ratio of MgO / Al2O3, thereby achieving a density of the glass fiber composition of 2.610 g / cm. 3 The elastic modulus of the glass fiber is ≧94.0GPa, and the specific elastic modulus is ≧3.67*10 6 m.

The present invention discloses a method and device for preparing calcium-removed magnesium-rich recrystallized dolomite, the method comprising: preparing a reaction solution 1, wherein the Ca in the reaction solution 1 is 2+ Mg 2+ 、Na + The ion concentration is equal to the Ca in standard seawater 2+ Mg 2+ 、Na + Ion concentration value; prepare reaction solution 2, CO3 in reaction solution 2 2‑ Ions and Ca in reaction solution 1 2+ The ion concentration is consistent, and the Na + Ions and Na in reaction solution 1 + The ion concentration is consistent; a configured basic reaction solution is added to the reactor; the prepared magnesium-rich carbonate seed is added to the basic reaction solution in the reactor; reaction solution one and reaction solution two are injected into a reaction vessel via a peristaltic pump, and a gas source of different components is supplied during the reaction to adjust the pH value of the solution in the reaction vessel. The pH is lowered and raised in a continuous alternating manner day and night, and a dolomite sample with a high magnesium-calcium ratio is obtained after 30-60 days. The present invention achieves the preparation of dolomite by decalcification and magnesium-rich recrystallization under normal temperature and pressure laboratory conditions.

The utility model relates to the technical field of external refining forming, in particular to an ultrahigh magnesium spheroidizing cored wire external refining forming device, which is characterized in that the inner wall of a ladle refining furnace body is rotatably connected with an internal barrel, the inner wall of the internal barrel is fixedly provided with an inner ring gear, and the upper end of an external connecting plate is fixedly connected with a middle connecting block; the outer wall of the stirring rod is fixedly connected with a stirring paddle and a driving gear, one end of the driving gear is in meshed connection with a driven gear, and when the stirring rod rotates, the driving gear is driven to synchronously rotate, so that the driven gear drives the inner barrel to rotate through the inner ring gear, and the rotating direction of the inner barrel is opposite to that of the stirring rod; at the moment, the stirring range of the stirring paddle is increased along with rotation of the inner barrel, the stirring efficiency is high, and the problem that the stirring efficiency is low due to the fact that a stirring structure of an existing cored wire external refining forming device is fixed to a certain position and the stirring range is limited when a cored wire enters molten steel for stirring is solved.

The invention provides a composition with high magnesium absorption and utilization rate and capable of improving emotion and sleep as well as a preparation method, application and related products of the composition, and belongs to the technical field of magnesium-containing compositions. The composition provided by the invention comprises the following components: magnesium glycinate, magnesium taurine and magnesium malate, and further comprises gamma-aminobutyric acid, vitamin B6, vitamin D and phospholipid. The composition can be made into a variety of dosage forms including tablets. Animal experiments show that the composition provided by the invention can achieve a higher magnesium utilization rate and better effects of improving anxiety and depression and improving sleep.

The invention discloses a magnesium removal method for a high-magnesium-content lithium leaching solution. The high-magnesium-content lithium leaching solution is a lithium sulfate solution obtained by roasting, acidifying, leaching and impurity removal of spodumene ore; the magnesium removal method comprises the following steps: introducing a sodium hydroxide solution into the lithium leaching solution with high magnesium content, synchronously adding calcium hydroxide and magnesium hydroxide seed crystals, and carrying out solid-liquid separation by using a filtering device after complete reaction. By optimizing the reaction raw materials and controlling and adjusting the process, the magnesium removal and filtration efficiency can be obviously improved under the condition that the equipment process flow is not adjusted on a production line, so that the treatment yield is improved, and the production cost is saved.

The invention discloses an Al-Mg-Zn aluminum alloy with ultrahigh strength, high toughness and high magnesium content and a preparation method of the Al-Mg-Zn aluminum alloy. The alloy contains 83.30 wt%-89.51 wt% of Al, 6.0 wt%-9.9 wt% of Mg, 4.01 wt%-5.50 wt% of Zn, 0.025 wt%-0.6 wt% of Si and at least one of Mn, Cu, Zr, Sc, Ti, Be and Sb, wherein the total content of the Mn, the Cu, the Zr, the Sc, the Ti, the Be and the Sb is not larger than 0.7 wt%. The contents of Mg, Zn and Si meet the relational expression: 0.83 < = [(2 * Mg) + Si] / [(3 * Zn)-(0.2 * Mg)] < = 2.03. The preparation method of the aluminum alloy deformation processing material comprises the following steps: (1) manufacturing an aluminum alloy cast ingot; (2) homogenizing heat treatment; (3) processing into a processing material; (4) solid solution heat treatment; (5) cooling to room temperature; and (6) aging treatment. The aluminum alloy has low density, high strength and high fracture toughness.

This application discloses an air-suspension granulation technology for preparing spherical magnesium nitrate hexahydrate, belonging to the field of magnesium nitrate hexahydrate granulation technology. It includes magnesium nitrate hexahydrate purification and granulation. This application incorporates a hydrophobic agent to form a robust microscopic protective layer, which effectively blocks water molecule intrusion and has a low moisture absorption rate. Furthermore, the air-suspension granulation tower technology is redesigned to better handle surface free water, resulting in higher magnesium nitrate purity, better crystal form, and better applicability to various magnesium nitrate applications. The particle size of the magnesium nitrate hexahydrate particles prepared by this application can be adjusted according to the air velocity, ranging from 0.5 to 12 mm. This technology has a wide range of applications, low cost, high sphericity, and eliminates the need for subsequent separate processing of broken particles, reducing labor costs and improving production efficiency. The magnesium nitrate hexahydrate also exhibits high purity, few impurities, and high product quality.

This invention relates to the field of phosphate rock beneficiation technology. It discloses a composite beneficiation method for removing iron, aluminum, silicon, and magnesium impurities from phosphate rock, comprising the following steps: S1, crushing and grinding phosphate rock to remove magnesium; S2, adding water to the demagnesified phosphate concentrate at a concentration controlled at 15-20%, and classifying it using a hydrocyclone to obtain coarse and fine products; S3, subjecting the coarse product to aeration reverse flotation for desiliconization; S4, concentrating the fine product and then subjecting it to aeration flotation for desiliconization, iron removal, and aluminum removal; S5, merging high-quality phosphate concentrate one and high-quality phosphate concentrate two to obtain a low-silicon, low-magnesium, low-iron, and low-aluminum high-quality phosphate concentrate; S6, merging the tailings as total tailings. This invention effectively solves the problem of high magnesium, silicon, iron, and aluminum impurity content in phosphate rock due to depletion, which is difficult to effectively remove. It is an easy-to-operate and easily industrialized composite beneficiation process for efficient phosphate rock impurity removal.

The invention provides a pre-magnesium-removal wet processing method for nickel-cobalt mixed hydroxides, and relates to the field of wet metallurgy. The pre-magnesium-removal wet treatment method of the nickel-cobalt mixed hydroxide comprises the following steps: mixing the nickel-cobalt mixed hydroxide with a first washing solution, and carrying out first slurrying treatment; adding an acid solution into the ore pulp subjected to the first pulpifying treatment, stirring, and carrying out first solid-liquid separation to obtain first washing slag and first filtrate; mixing the first washing slag with a second washing solution, carrying out second pulpifying treatment, adjusting the pH value of the ore pulp subjected to the second pulpifying treatment to 6.8-7.2, introducing CO2 gas, and carrying out carbonization reaction to obtain carbonized ore pulp; and carrying out second solid-liquid separation on the carbonized ore pulp to obtain a pre-magnesium-removed solid and a second filtrate. According to the method, the high magnesium removal efficiency can be achieved under the mild condition, loss of metal such as nickel and cobalt is reduced to the maximum extent, and the method has the advantages of being low in acid consumption, low in water consumption and short in process, and has the feasibility of continuous amplification.

A planting method for tea with high magnesium content relates to the technical field of tea planting and specifically comprises the following steps: S1, before planting, applying a magnesium fertilizer to improve soil; s2, tea trees are planted in the soil improved in the S1, and base fertilizer is applied to improve the soil structure; s3, in the growing period of the tea trees planted in the S2, magnesium fertilizer topdressing is conducted in multiple times in combination with drip irrigation; s4, after the tea trees in the S3 grow up, spraying a magnesium glycinate solution to leaves of the tea leaves in the young shoot growing period of the tea trees; s5, picking the tea leaves entering the picking period in the tea trees in the step S4; the method disclosed by the invention is simple and easy to implement, the operation of each step is easy to master, and the method is suitable for large-scale popularization, can meet the requirements of the market on the high-magnesium functional tea and has good economic benefits and social benefits.

This invention relates to a method for treating and utilizing high magnesium-to-sulfur ratio chlorine-containing wastewater, belonging to the field of environmental protection. This invention utilizes inexpensive calcium alkali to treat high magnesium-to-sulfur ratio chlorine-containing wastewater. During the treatment process, dilute hydrochloric acid is used as a circulation starter. Taking advantage of the difficult-to-remove chloride ions in the wastewater, the calcium alkali is used to generate calcium chloride solution, thereby continuously recovering sulfate ions from the high magnesium-to-sulfur ratio wastewater. Magnesium is converted into magnesium hydroxide, transforming into valuable by-products such as calcium chloride and gypsum, thus achieving resource utilization of waste. This method reduces the environmental impact of wastewater discharge, while also reducing treatment costs and achieving resource recycling. It is highly feasible for existing enterprises and has significant economic, social, and environmental benefits.

The invention belongs to the technical field of wet smelting, and provides a method for continuously preparing high-activity magnesium oxide slurry from superfine magnesium oxide powder and applying the high-activity magnesium oxide slurry to cobalt precipitation and nickel precipitation, and the method comprises the following steps: S1, selecting light calcined magnesium oxide meeting the quality requirement to prepare the superfine magnesium oxide powder meeting the quality requirement; s2, superfine magnesium oxide powder is conveyed to a high-position stock bin, quantitative and continuous feeding is conducted through a metering feeding device, and the superfine magnesium oxide powder is continuously mixed with water or cobalt precipitation pre-liquid or nickel precipitation pre-liquid by means of a Venturi ejector; s3, performing high-shear emulsification dispersion to obtain high-activity magnesium oxide slurry; and S4, directly conveying to a cobalt and nickel deposition reaction system to realize seamless joint between magnesium oxide continuous pulping and continuous cobalt and nickel deposition processes. The invention solves the technical problems of easy agglomeration and caking of magnesium oxide slurry, poor activity, poor cobalt and nickel deposition performance, low grade of crude cobalt hydroxide or nickel cobalt hydroxide product, high content of impurity magnesium, high unit consumption of magnesium oxide and the like in the traditional process.

The invention provides extraction sewage treatment equipment and process for extracting lithium from brine with a high magnesium-lithium ratio, and relates to the technical field of water pollution treatment, the extraction sewage treatment equipment comprises a reaction tank, a dosing mechanism, a slag scraping mechanism and a slag removing mechanism; the slag scraping mechanism comprises a scraping plate and two threaded lead screws, the scraping plate is arranged in the reaction tank, the two threaded lead screws are in threaded connection with the scraping plate, and the left ends of the two threaded lead screws are rotationally connected with first connecting seats. According to the scheme, the slag removal frame and the filter screen are in an inclined state through continuous rightward movement of a scraper blade under the cooperation of an overturning gear and an overturning toothed plate, so that the separated floccule scum can be further treated conveniently, and lime milk can be in better full contact with lower-layer sewage after the floating scum is cleaned, so that the reaction rate is increased, and the reaction time is shortened. And scum can be prevented from being taken out by water flow, so that secondary entrainment of heavy metals and organic matters is reduced, the subsequent recycling or discharging standard is met, and the risk of secondary pollution is avoided.

This invention discloses a ternary composite extraction system for iron-containing brine with a high magnesium-to-lithium ratio and its application. The ternary composite extraction system includes: a main extractant, a co-extractant, a phase behavior modifier, and a diluent; wherein the main extractant includes diphenyl octyl phosphate, the co-extractant includes di(2-ethylhexyl)phosphoric acid, and the phase behavior modifier includes diethyl succinate. This invention proposes a ternary composite extraction system containing DPOP, P2O4, and DES, and establishes a differentiated extraction-back-extraction pathway for complex iron-containing systems. It enables effective lithium recovery through water back-extraction and controls the distribution behavior of iron in the system, thereby simplifying the process and improving the stability of the organic phase cycle.

The invention relates to an oxygen pressure leaching treatment method and an oxygen pressure leaching treatment system for high-magnesium zinc concentrate. The oxygen pressure leaching treatment system comprises a first pipeline, N high-pressure autoclaves, a second pipeline, a third pipeline, a fourth pipeline, a plurality of ninth valves, a tenth valve, a twelfth valve, a flash drum and a solid-liquid separation unit, and the flash drum is communicated with the solid-liquid separation unit; the autoclave comprises a tank body, the tank body is provided with feed ports, discharge ports, air inlets and a manhole, a stirring mechanism is arranged in the tank body, all the feed ports are connected to a first pipeline in parallel, all the discharge ports are connected to a third pipeline in parallel, and all the air inlets are connected to a second pipeline in parallel. According to the oxygen pressure treatment system, deposited and scaled magnesium slag can be regularly cleaned for a single autoclave through the manhole, all the autoclaves can be standby for each other, and during cleaning, by controlling opening and closing of related valves, other autoclaves can be connected in series so as to meet the oxygen pressure leaching process, continuous operation of other autoclaves is guaranteed, and the service life of the autoclaves is prolonged. The operation continuity and the treatment efficiency of the whole oxygen pressure treatment system are favorably improved.

This disclosure aims to provide magnesium glycinate with a high magnesium concentration. [Solution] Magnesium glycinate having a first peak with its peak in the range where 2θ is between 11.1° and 12.1°, and a second peak with its peak in the range where 2θ is between 13.3° and 14.3°, in its powder X-ray diffraction spectrum.

The application provides an extraction sewage treatment equipment and process for extracting lithium from high-magnesium-lithium-ratio brine, relates to the technical field of water pollution treatment, and comprises a reaction tank, a dosing mechanism, a slag scraping mechanism and a slag removal mechanism. The slag scraping mechanism comprises a scraper and two threaded lead screws. The scraper is arranged in the interior of the reaction tank. The two threaded lead screws are threadedly connected with the scraper. First connecting seats are rotationally connected to the left ends of the two threaded lead screws. The scraper continuously moves to the right. The slag removal frame and the filter screen are in an inclined state under the cooperation of the turnover gear and the turnover toothed plate, so that the separated flocculent scum can be further treated. After the floating scum is cleaned, the lime milk and the lower layer of sewage can be better contacted, so that the reaction rate is improved. The scum can be prevented from being carried out by the water flow, so that the secondary entrainment of heavy metals and organic matters is reduced, subsequent reuse or discharge standards are met, and the risk of secondary pollution is avoided.

The invention belongs to the technical field of new energy materials, and discloses a preparation method of a lithium magnesium alloy negative electrode material with high magnesium content. 35%-45% of lithium; 2%-4% of aluminum; 1%-2% of zinc; 0.3%-0.8% of calcium; 0.1%-0.5% of lanthanum; 0.05%-0.3% of neodymium; comprising the following steps: screening raw materials, and removing obviously oxidized and damaged parts on the surface; magnesium, lithium, aluminum, zinc, calcium, lanthanum and neodymium are respectively put into an ultrasonic cleaning machine; according to the method, the raw material ratio is optimized, aluminum, zinc, calcium and rare earth elements lanthanum and neodymium are added, a segmented feeding process is combined, vacuum melting and binary gas stirring are combined, and the problem of composition segregation of a traditional melting method is effectively solved; wherein the rare earth elements lanthanum and neodymium can significantly refine grains, improve the distribution uniformity of the magnesium element and reduce the impurity content, so that the electrochemical stability of the alloy is significantly enhanced, and the cycle performance is superior to that of similar alloys in the prior art.

The invention discloses a copper-nickel sulfide ore flotation composite foaming agent as well as a preparation method and application thereof, belongs to the technical field of mineral separation, and solves one of the problems of weak bubble stability, poor flotation selectivity, low copper-nickel recovery rate and high magnesium content of concentrate in a copper-nickel sulfide ore flotation separation process in the prior art. Raw materials of the copper-nickel sulfide ore flotation composite foaming agent comprise short-chain higher alcohol, ethoxylated low-carbon alcohol ether and sodium oleate. When the copper-nickel sulfide ore flotation composite foaming agent is used for copper-nickel sulfide ore flotation, the grade and the recovery rate of copper-nickel concentrate can be remarkably improved, and the content of MgO in the concentrate is reduced.

The application discloses a preparation process of special magnesium oxide and relates to the technical field of special magnesium oxide preparation, and comprises the following steps: crushing magnesite, processing the magnesite into a plurality of ore blocks, screening the ore blocks with high magnesium content for further crushing, setting the initial rotating speed of a converter, starting the converter and preheating, pouring the ore blocks into the converter, continuously heating the converter, when the temperature and heating time of the converter reach the requirements, stopping the heating and closing the converter, cooling the converter to the ambient temperature, completing the first-time burning of the magnesium oxide, resetting the rotating speed of the converter, starting the converter and heating, when the temperature and heating time of the converter reach the requirements, stopping the heating and closing the converter, cooling the converter to the ambient temperature, taking out the special magnesium oxide after repeated burning, mixing and bagging, and completing the preparation of the special magnesium oxide. The repeated calcination method is adopted, the prepared magnesium oxide has high catalytic performance, and thus the combustion performance of double-base propellant is improved.

The present invention relates to the technical field of pharmaceutical excipients, and particularly to a high-purity, light-weight and highly active magnesium oxide and a preparation method thereof, comprising the following steps: preparing a magnesium sulfate solution and a precipitant, stirring and mixing the magnesium sulfate solution and the precipitant in a high-speed spiral manner to obtain basic magnesium carbonate hydrate, and calcining the basic magnesium carbonate hydrate at a stepwise progressive temperature to obtain magnesium oxide. The present invention further refines and purifies the semi-finished products of the magnesium solution and the precipitant, adopts the method of the present invention to prepare a specific crystal form precursor, basic magnesium carbonate hydrate, and controls the calcination time node according to the stepwise progressive calcination method to obtain high-purity, light-weight and highly active magnesium oxide. Compared with the existing magnesium oxide products on the market, the high-purity, light-weight and highly active magnesium oxide prepared by the present invention has a higher magnesium oxide content, and better quality and service performance.

The application discloses a hydrotalcite-derived material, a preparation method and application thereof, and belongs to the field of inorganic nanometer material metal ion adsorption; the nanometer material prepared by the application is an oxide derived from layered structure magnesium-aluminum hydrotalcite; the nanometer material is in a nanometer sheet structure; in the preparation process, a magnesium-aluminum hydrotalcite material with a high magnesium / aluminum atomic ratio is used as a precursor, and high-temperature calcination treatment is carried out at a specific temperature to convert the magnesium-aluminum hydrotalcite material into a derived oxide; the derived oxide has a high ion adsorption capacity for trivalent metal ions, and ion enrichment products can return to the layered structure of the hydrotalcite.

The invention discloses an Al-Mg-Zn aluminum alloy with high strength and toughness, fatigue resistance and high magnesium content and a preparation method of the Al-Mg-Zn aluminum alloy. The aluminum alloy comprises the following components in percentage by weight: 86.16%-92.27% of Al, 6.1%-9.5% of Mg, 1.6%-3.0% of Zn, 0.025%-0.099% of Si, and at least one of Mn, Cu, Zr, Sc, Ti, Be and Sb, wherein the total content of the at least one of Mn, Cu, Zr, Sc, Ti, Be and Sb is not more than 0.75%. The preparation method of the aluminum alloy deformation processing material comprises the following steps: (1) manufacturing an aluminum alloy cast ingot; (2) homogenizing heat treatment; (3) processing into a processing material; (4) solid solution heat treatment; (5) cooling to room temperature; and (6) aging treatment. The aluminum alloy material has low density, high strength and excellent fatigue resistance.

The utility model relates to the technical field of aluminum alloy manufacturing equipment, in particular to a high-magnesium-content Al-Mg-Si alloy magnesium adding device which comprises an outer cylinder arranged in an open mode. One end of the T-shaped ventilation device is located at one end of an opening of the outer barrel, the conical cover plate is welded to the outer circumference of a ventilation outlet, extending into the outer barrel, of the other end of the T-shaped ventilation device, the molten aluminum barrel is defined by the inner wall of the outer barrel and the conical cover plate, and the vacant magnesium barrel is located below the molten aluminum barrel. The frame vacant magnesium cylinder is connected with a bearing arm in a welding manner; a pressing device is connected to the outer portion of the T-shaped ventilation device in a welded mode and provided with a handle, the large opening end of the conical cover plate is welded to a supporting ring, and the large opening end of the conical cover plate is movably clamped in the outer cylinder through the supporting ring. According to the method, the utilization rate of magnesium is increased through isolation design and accurate control in the vacuum environment, meanwhile, the purity of molten aluminum is guaranteed, and an effective technical means is provided for manufacturing the Al-Mg-Si alloy with the high magnesium content.

The invention relates to a method and a device, by means of which particles with a high magnesium content can be obtained from sea water. The particles can be magnesium hydroxide for example as well as other water-insoluble magnesium salts, such as magnesium sulfate, magnesium carbonate, etc., for example. The particles are produced in a precipitation process using a suitable alkali reagent. When the precipitation is carried out using a nozzle construction according to the invention and / or while adding auxiliary reagents, the size of the obtained particles and the yield thereof can be influenced within a specified range. The aqueous suspension obtained from the process can be further processed in order to produce different products, up to metallic magnesium for metallurgy, using existing technical methods.

The application provides a pre-magnesium removal wet treatment method of nickel-cobalt mixed hydroxide, and relates to the field of hydrometallurgy. The pre-magnesium removal wet treatment method of nickel-cobalt mixed hydroxide comprises the following steps: mixing the nickel-cobalt mixed hydroxide with a first washing liquid, and performing first slurry treatment; adding an acidic solution into the slurry after the first slurry treatment, stirring, performing first solid-liquid separation, and obtaining first washing residue and first filtrate; mixing the first washing residue with a second washing liquid, and performing second slurry treatment; adjusting the pH of the slurry after the second slurry treatment to 6.8-7.2, introducing CO2 gas, performing carbonization reaction, and obtaining slurry after carbonization; performing second solid-liquid separation on the slurry after carbonization, and obtaining pre-magnesium removal solid and second filtrate. The application can realize high magnesium removal efficiency under mild conditions, maximally reduce the loss of metals such as nickel and cobalt, and has the advantages of less acid consumption, less water consumption and short process, so that the application has the feasibility of continuous amplification.

The invention discloses a preparation method and a preparation device of calcium-removed magnesium-rich recrystallized dolomite. The method comprises the following steps: preparing a reaction liquid I, wherein the concentration of Ca < 2 + >, Mg < 2 + > and Na < + > ions in the reaction liquid I is equal to the concentration value of Ca < 2 + >, Mg < 2 + > and Na < + > ions in standard seawater; preparing a reaction solution II, wherein the concentration of CO3 < 2-> ions in the reaction solution II is consistent with that of Ca < 2 + > ions in the reaction solution I, and the concentration of Na < + > ions in the reaction solution II is consistent with that of Na < + > ions in the reaction solution I; adding the prepared basic reaction solution into a reactor; adding the prepared magnesium-rich carbonate rock seeds into the basic reaction solution in the reactor; and injecting the reaction liquid I and the reaction liquid II into a reaction container through a peristaltic pump, supplying gas sources with different components in the reaction process to adjust the pH value of the solution in the reaction container, performing pH reduction and pH increase adjustment in a day-night continuous alternating manner, and obtaining a dolomite sample with a high magnesium-calcium ratio after 30-60 days. According to the method, dolomite is prepared in a calcium-removing magnesium-rich recrystallization mode under the conditions of normal temperature and normal pressure in a laboratory.