A metallurgical slag online monitoring and analysis method and system

Abstract

The present invention provides an online monitoring and analysis method and system for metallurgical slag, the online monitoring and analysis method for metallurgical slag comprising: establishing a standard working curve of the element to be analyzed, completing the debugging preparation work of the element detection device; digesting the metallurgical slag by a normal temperature digestion method or a high temperature melting digestion method to obtain a slag digestion solution; wherein the normal temperature digestion method adopts ultrasonic digestion, and the high temperature melting digestion method adopts ultrasonic emulsification leaching; and at least one method selected from ICP spectroscopy, electrode method and titration analysis is used to detect the element content in the slag digestion solution. The online monitoring and analysis system for smelting slag provided by the present invention can take into account both timeliness and accuracy, and meet the demand for real-time monitoring of slag composition during the smelting process.

Description

Technical Field

[0001] The present invention relates to the technical field of metal smelting process control, and in particular to an online monitoring and analysis method and system for metallurgical slag. Background Art

[0002] In the process of metal smelting, different types of slag-forming agents need to be added during the smelting process according to the differences in the composition and properties of the metal being smelted, so as to obtain slag with different compositions and physical properties. Therefore, the composition of slag is an important parameter in the process of metal smelting. In the process of metal smelting, the composition of slag needs to be analyzed frequently to adjust the type and amount of slag-forming agents added. In order to understand the composition of metallurgical slag in a timely and accurate manner, the composition analysis of metallurgical slag needs to take into account both timeliness and accuracy.

[0003] In the prior art, the analysis methods of metallurgical slag include X-ray fluorescence spectrometry melting film method, X-ray fluorescence spectrometry powder pressing method and laser induced breakdown spectroscopy rapid analysis technology (LIBS). Among them, X-ray fluorescence spectrometry melting film method is a common detection technology for quantitative analysis of slag in various metallurgical enterprises at present, which can accurately complete the quantitative detection of elements such as calcium, magnesium, aluminum, silicon, iron and manganese in metallurgical slag. Its detection time is 40-60 minutes, which is time-consuming; X-ray fluorescence spectrometry powder pressing method is carried out using the analysis software of X-ray fluorescence spectrometer, and its detection rate is 15-20 minutes. Since the particle size and surface finish of the sample of the pressing method have a great influence on the detection results of magnesium, aluminum and silicon, the accuracy of the detection results is poor; LIBS is a new detection technology that has been gradually applied in the past 10 years. Through preliminary research, experimental system design and establishment of free calibration mathematical model, the mass fraction of each component in the slag is calculated, and the accuracy of the detection result depends on the measurement repeatability and the matching degree of the mathematical model. The relative error of calcium, magnesium, aluminum and iron is between 5-20%, and the accuracy cannot be guaranteed. Summary of the invention

[0004] The problem solved by the present invention is how to provide an online monitoring and analysis method for metallurgical slag that takes into account both timeliness and accuracy.

[0005] In order to solve at least one aspect of the above problems, the present invention provides a method for online monitoring and analysis of metallurgical slag, comprising the following steps:

[0006] Step S1, digesting the metallurgical slag by a normal temperature digestion method or a high temperature melting digestion method to obtain a slag digestion solution; wherein the normal temperature digestion method adopts ultrasonic digestion, and the high temperature melting digestion method adopts ultrasonic emulsification leaching;

[0007] Step S2, analyzing the slag digestion solution by at least one of ICP spectroscopy, electrode method and titration analysis, and obtaining the element content in the metallurgical slag by a pre-established element standard working curve.

[0008] Preferably, in step S1, the room temperature digestion method comprises: mixing the metallurgical slag with a composite digestion solution at room temperature, and then digesting the slag by ultrasonic wave to obtain the slag digestion solution.

[0009] Preferably, in step S1, the high-temperature melting digestion method comprises: mixing the metallurgical slag with a solid flux and then melting the mixture at a high temperature into a liquid to obtain a eutectic, then mixing the eutectic after rapid cooling with a leachate, then using ultrasonic emulsification leaching to obtain a sample leachate, and mixing the sample leachate with an acidifying solution to obtain the slag digestion solution; or, mixing the metallurgical slag with a solid flux and then melting the mixture at a high temperature into a liquid to obtain a eutectic, then mixing the eutectic after rapid cooling with an acidifying solution, and then using ultrasonic emulsification leaching to obtain the slag digestion solution.

[0010] Preferably, in step S2, the ICP spectroscopy includes using an ICP-AES spectrometer to detect the content of calcium, magnesium, silicon, aluminum, iron, manganese, chromium, vanadium, titanium, phosphorus, sulfur or copper in the slag digestion solution.

[0011] Preferably, in step S2, the electrode method includes using a multifunctional ion meter to detect the content of fluorine in the slag digestion solution.

[0012] Preferably, in step S2, the titration analysis method includes using a redox titration analysis method using a potassium dichromate standard solution or a potassium permanganate standard solution to detect the content of ferrous elements in the slag digestion solution.

[0013] Preferably, the element standard working curve includes at least one of a calcium standard working curve, a magnesium standard working curve, a silicon standard working curve, an aluminum standard working curve, an iron standard working curve, a manganese standard working curve, a chromium standard working curve, a vanadium standard working curve, a titanium standard working curve, a copper standard working curve, a fluorine standard working curve, a sulfur standard working curve, a phosphorus standard working curve and a ferrous standard working curve.

[0014] The present invention establishes a standard working curve of the element to be analyzed in advance and prepares for debugging the element detection device. After obtaining the slag digestion solution, the sample can be quickly and continuously injected. Then, a normal temperature digestion method or a high temperature melting digestion method is selected according to the type of the smelting slag. When the normal temperature digestion method is adopted, ultrasonic waves are used to digest the sample, while when the high temperature melting digestion method is adopted, ultrasonic emulsification leaching is used to avoid the problem of too long digestion time caused by the heating and cooling processes. Then, at least one method of ICP spectroscopy, electrode method and titration analysis is selected according to the type of the element to be analyzed to detect the element in the smelting slag. Ultrasonic digestion or emulsification leaching can avoid the problem of long time caused by heating and cooling during digestion or leaching, and selecting different digestion methods according to the type of smelting slag can further save digestion time and reduce operation difficulty. The digestion method can fully leach the elements in the smelting slag and improve the detection accuracy. ICP spectroscopy, electrode method and titration analysis have fast detection speed and high detection accuracy, and can be applied to the detection of most elements. Therefore, the online monitoring and analysis system for smelting slag provided by the present invention can take into account timeliness and accuracy, and meet the needs of real-time monitoring of slag composition during the smelting process.

[0015] Another object of the present invention is to provide an online monitoring and analysis system for metallurgical slag, comprising a digestion tank, a leaching tank and an element detection device; wherein the digestion tank is used to digest the metallurgical slag by ultrasound; the leaching tank is used to emulsify and leach elements in the metallurgical slag by ultrasound; and the element detection device is used to detect the element content in the slag digestion solution.

[0016] Preferably, it also includes a heating device, a cooling device and a liquid adding device; wherein the heating device is used to heat and melt the metallurgical slag and the solid solvent into a eutectic; the cooling device is used to rapidly cool the eutectic; and the liquid adding device is used to quantitatively add the required test solution.

[0017] Preferably, the liquid adding device comprises a constant temperature liquid storage tank and a transfer pump.

[0018] The metallurgical slag online monitoring and analysis system provided by the present invention has the same beneficial effects as the metallurgical slag online monitoring and analysis method compared with the prior art, which will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Flow chart of the on-line monitoring and analysis method for metallurgical slag in an embodiment of the present invention;

[0020] Figure 2 This is an example diagram of online monitoring and analysis of blast furnace slag in the steelmaking process in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below.

[0022] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention can be combined with each other. The meanings of the terms "comprise", "include", "contain", and "have" are non-restrictive, that is, other steps and other components that do not affect the results can be added. The above terms cover the terms "consisting of..." and "consisting essentially of...". Unless otherwise specified, materials, equipment, and reagents are all commercially available. At the same time, it should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable where appropriate, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here.

[0023] The embodiment of the present invention provides a method for online monitoring and analysis of metallurgical slag, such as Figure 1 As shown, the following steps are included:

[0024] Step S1, digesting the metallurgical slag by a normal temperature digestion method or a high temperature melting digestion method to obtain a slag digestion solution; wherein the normal temperature digestion method adopts ultrasonic digestion, and the high temperature melting digestion method adopts ultrasonic emulsification leaching;

[0025] Step S2, analyzing the slag digestion solution by at least one of ICP spectroscopy, electrode method and titration analysis, and obtaining the element content in the metallurgical slag by a pre-established element standard working curve.

[0026] In order to improve the timeliness of online analysis of smelting slag, after sampling in the smelting furnace, the smelting slag is placed in a sealed metal can and quickly transported to the testing laboratory through a special sample delivery air duct, and then the smelting slag sample is quickly ground through a vibration mill.

[0027] In addition, a standard working curve of elements is established in advance, and preparations for debugging the element detection device are made, so that after obtaining the slag digestion solution, sampling and analysis can be carried out immediately, and data on element content can be obtained through the standard working curve.

[0028] Among them, the element standard working curve includes at least one of a calcium standard working curve, a magnesium standard working curve, a silicon standard working curve, an aluminum standard working curve, an iron standard working curve, a manganese standard working curve, a chromium standard working curve, a vanadium standard working curve, a titanium standard working curve, a copper standard working curve, a fluorine standard working curve, a phosphorus working curve, a sulfur working curve and a ferrous standard working curve; the debugging equipment work of the element detection device is completed, so that the element detection device is in a state of waiting for sampling, and the sample can be directly sampled and tested after processing, thereby saving time.

[0029] It should be understood that the relevant standard working curve is established according to the elements that need to be detected in the smelting slag, and the element detection devices used to establish the standard working curve are different according to the different element detection devices used to detect different elements, that is, the element detection and the establishment of the element standard curve are completed using the same element detection device; in addition, the online monitoring and analysis method of smelting slag can be applied to the online monitoring and analysis of elements in the smelting slag including calcium oxide, calcium fluoride, magnesium oxide, aluminum oxide, silicon dioxide, titanium dioxide, vanadium oxide, sulfur, phosphorus, iron, manganese, chromium, nickel, cobalt, boron, zinc, molybdenum, copper, niobium, arsenic, tin, antimony, zirconium and cerium. The element standard working curve provided in this embodiment is used as an example and is not used to limit the scope of protection of the present invention.

[0030] Exemplarily, a calcium standard working curve, a magnesium standard working curve, a silicon standard working curve, an aluminum standard working curve, an iron standard working curve, a manganese standard working curve, a chromium standard working curve, a vanadium standard working curve, a titanium standard working curve and a copper standard working curve are established by an ICP-AES spectrometer, and the specific establishment steps include:

[0031] Prepare calcium standard solution, magnesium standard solution, silicon standard solution, aluminum standard solution, iron standard solution, manganese standard solution, chromium standard solution, vanadium standard solution, titanium standard working curve and copper standard solution suitable for the metallurgical slag to be tested; draw 0-100 mL of different types of standard solutions into a container, add a composite digestion solution equal to the metallurgical slag digestion, add 5-50 mL of internal standard solution, mix well and make up to volume, and detect by ICP-AES spectrometer to obtain a standard curve;

[0032] The steps for establishing the standard curve of fluorine element include:

[0033] Prepare a fluorine element standard solution suitable for the metallurgical slag to be tested; draw 0-100 mL of the fluorine element standard solution respectively, add 10-100 mL of an ionic strength agent to adjust the pH of the solution to 6.0-7.0, use distilled water to make up the volume and shake well, and detect with a multifunctional ion meter to obtain a standard curve;

[0034] Correspondingly, the ferrous ion standard curve is obtained by titrating ferrous ion standard solutions of different concentrations with oxidizing standard solutions such as potassium dichromate standard solution or potassium permanganate solution.

[0035] In step S1, the smelting slag includes smelting slag produced in steelmaking, ironmaking, copper smelting and other non-ferrous metal smelting processes, and the scope of application includes blast furnace slag, converter slag, secondary smelting slag, refined slag, pre-melted slag, electric furnace slag, copper slag, sintered pellets and blast furnace sintered material. In addition, it can also be used for the detection and analysis of metallurgical mineral products such as fluorite, limestone, dolomite, metallurgical lime and iron ore.

[0036] The room temperature digestion method comprises mixing the metallurgical slag with a composite digestion solution at room temperature, and then performing ultrasonic digestion to obtain a slag digestion solution; wherein the composite digestion solution comprises at least one of hydrochloric acid, nitric acid, sulfuric acid, perchloric acid, hydrobromic acid, hydroiodic acid, citric acid, tartaric acid and hydrofluoric acid, and also comprises an organic reagent. The composite digestion solution can react with the metallurgical slag to dissolve the elements in the metallurgical slag for detection and analysis, and the ultrasonic wave can accelerate the reaction rate of the composite digestion solution and the metallurgical slag through high-frequency vibration, and make the dissolved elements fully dispersed in the composite digestion solution. Moreover, since ultrasonic digestion replaces heating digestion, the problem of a long time caused by the heating and cooling processes is avoided, and the method is suitable for online monitoring.

[0037] Exemplarily, the room temperature digestion method comprises the following steps:

[0038] Step T1, grinding the metallurgical slag by vibration for 10-30s using a tungsten carbide bowl or a high manganese / chromium steel bowl, weighing 0.1-0.5g of the sample into a beaker, accurate to 0.1mg, and recording the weighed mass;

[0039] Step T2, add 10-500 mL of the composite digestion solution into a beaker, turn on the ultrasonic device, digest the solution in the beaker by ultrasonic waves, and keep stirring for 1-10 minutes to complete the digestion.

[0040] The high-temperature melting digestion method comprises melting metallurgical slag and solid flux at a high temperature of 400-1000°C into a liquid state to obtain a eutectic, then mixing the eutectic after rapid cooling with a leachate, then using ultrasonic emulsification leaching to obtain a sample leachate, and mixing the sample leachate with an acidifying solution to obtain a slag digestion solution; or, mixing the metallurgical slag with a solid flux and then melting them at a high temperature of 400-1000°C into a liquid state to obtain a eutectic, then mixing the eutectic after rapid cooling with an acidifying solution, and then using ultrasonic emulsification leaching to obtain a slag digestion solution; wherein the solid flux comprises nitrates such as potassium nitrate, magnesium nitrate, lithium nitrate, strontium nitrate, copper nitrate, iron nitrate and manganese nitrate, permanganates such as potassium permanganate and sodium permanganate, chlorates and perchlorates such as sodium chlorate and potassium chlorate, chromates such as chromium trioxide, potassium chromate, sodium chromate and potassium dichromate, and acid anhydrides or other strong oxidizing oxygen-containing acid salts, peroxide Metal peroxides or other peroxides such as potassium, sodium peroxide and lithium peroxide, carbonates such as potassium carbonate, sodium carbonate and lithium carbonate, caustic alkalis such as potassium hydroxide and sodium hydroxide and other hydroxides, and acidic fluxes such as potassium pyrosulfate, sodium pyrosulfate and sodium sulfate; the leachate includes distilled water, acidic leachate or alkaline leachate, the alkaline leachate includes at least one of sodium hydroxide, potassium hydroxide and ammonia water, the acidic leachate includes at least one of hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, citric acid, tartaric acid and hydrofluoric acid; the acidizing solution includes at least one of hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, perchloric acid, hydrobromic acid, hydroiodic acid, citric acid, tartaric acid and hydrofluoric acid; the solid flux and the metallurgical slag are melted into liquid at high temperature to destroy the structure of the metallurgical slag, and then the elements in the eutectic are fully leached into the solution through the leachate, and the acidizing solution is added for acidification, so as to meet the detection and analysis conditions.

[0041] Among them, rapid cooling includes water bath cooling, flowing water cooling, ice salt bath cooling, bottom spray cooling or air cooling. By adopting the rapid cooling method, the cooling process of the eutectic can be completed in 5-20 seconds, which significantly shortens the cooling time.

[0042] Exemplarily, the high temperature melting digestion method comprises the following steps:

[0043] Step U1, grinding the metallurgical slag by vibration for 10-30s using a tungsten carbide bowl or a high manganese / chromium steel bowl, weighing 0.1-0.5g of the sample into a beaker, accurate to 0.1mg, and recording the weighed mass;

[0044] Step U2, adding weighed metallurgical slag into a nickel crucible containing 1-15 g of solid flux, and mixing the metallurgical slag and the solid flux evenly;

[0045] Step U3, placing the nickel crucible on an alcohol burner, burning until the metallurgical slag and the solid flux are completely melted, and maintaining for 1-30 seconds to obtain a eutectic;

[0046] Step U4, take out the nickel crucible and place its bottom in a cold water tank, and rapidly cool it for 5-30 seconds;

[0047] Step U5, pouring the rapidly cooled eutectic into a beaker containing 50-150 mL of sodium hydroxide, placing the beaker in an ultrasonic device, and performing ultrasonic emulsification leaching for 1-5 minutes to obtain a sample leachate;

[0048] Step U6, mix the sample leaching solution and 20-50 mL of an acidified solution with a concentration of 5-50% to obtain a slag digestion solution.

[0049] It should be understood that the room temperature digestion method or the high temperature melting digestion method is selected according to the type of smelting slag that needs to be digested. The room temperature digestion method is suitable for the digestion of non-ferrous metals and their alloys, steel materials, cement, metallurgical slag, metallic manganese, low-carbon ferromanganese or nickel, but is not suitable for oxides or mineral products with lithologic structures, while the high temperature melting digestion method is suitable for the digestion of all smelting slags; but compared with the high temperature melting digestion method, the room temperature digestion method is simpler to operate and takes less time, so the room temperature digestion method is preferred. When the room temperature digestion method cannot meet the requirements, the high temperature melting digestion method is used.

[0050] In addition, in order to further save digestion time, the temperature and amount of the added test solution are controlled during the digestion process so that the temperature and volume of the obtained slag digestion solution reach the preset values; that is, through pre-calculation, the test solution of appropriate temperature is added quantitatively so that the temperature and total volume of the slag digestion solution finally obtained meet the preset values, thereby avoiding the problem of long time caused by repeated volume setting and temperature reduction processes.

[0051] In step S2, the slag digestion solution is analyzed by at least one of ICP spectroscopy, electrode method and titration analysis, and the element content in the metallurgical slag is obtained by a pre-established element standard working curve.

[0052] Specifically, the ICP spectroscopy method includes using an ICP-AES spectrometer to detect the content of calcium, magnesium, silicon, aluminum, iron, manganese, chromium, vanadium, titanium or copper in the slag digestion solution; the electrode method includes using a multifunctional ion meter to detect the content of fluorine in the slag digestion solution; the titration analysis method includes using a potassium dichromate standard solution or a potassium permanganate standard solution redox titration analysis method to detect the content of ferrous elements in the slag digestion solution.

[0053] ICP-AES spectrometer, or inductively coupled plasma-atomic emission spectrometer, can quantitatively analyze element content through the intensity of characteristic spectral lines. It has a wide range of applications, high sensitivity, low detection limit, short detection time, and high degree of automation, making it suitable for online monitoring and analysis. Elements that cannot be detected by ICP spectroscopy are detected by other methods, such as detecting fluorine by electrode method to obtain the mass fraction of calcium fluoride in metallurgical slag, and detecting the ferrous element content by titration analysis.

[0054] After obtaining the content of elements in the smelting slag through ICP spectroscopy, electrode method or titration analysis, it can be used to monitor the "compliance" of the content of each component of the smelting slag, determine whether slag-making raw materials need to be added, and thus regulate the composition of the slag.

[0055] Another object of the present invention is to provide an online monitoring and analysis system for metallurgical slag, comprising a digestion tank, a leaching tank and an element detection device; wherein the digestion tank is used to digest the metallurgical slag by ultrasound; the leaching tank is used to emulsify and leach elements in the metallurgical slag by ultrasound; and the element detection device is used to detect the element content in the slag digestion solution.

[0056] In addition, the metallurgical slag online monitoring and analysis system also includes a heating device, a cooling device and a liquid adding device; wherein the heating device is used to heat and melt the metallurgical slag and the solid solvent into a eutectic; the cooling device is used to rapidly cool the eutectic; and the liquid adding device is used to quantitatively add the required test solution.

[0057] The heating device includes a flame burner, a high-frequency inductive coupling coil or a flat heating capacitor, and is preferably a flame burner. The flame burner includes a gas burner and an alcohol burner, which has a simple structure, low operation and maintenance costs, a high temperature, and can wrap the container to be heated more tightly, heat up faster, and has a more stable temperature, which can improve the heating and melting efficiency;

[0058] The digestion tank includes an ultrasonic generator, an energy converter and a stirrer, wherein the ultrasonic generator is used to convert the mains electricity into a high-frequency alternating current signal that matches the energy converter, the energy converter is used to receive the high-frequency alternating current signal generated by the ultrasonic generator and convert it into mechanical power (i.e., ultrasonic wave), and the stirrer is used to stir the solution during ultrasonic digestion;

[0059] Exemplarily, the digestion tank includes a stainless steel tank, an ultrasonic generator, an energy converter and a magnetic stirrer. When digesting at room temperature, a container containing smelting slag and a composite digestion solution is placed in the stainless steel tank, and the ultrasonic generator and the magnetic stirrer are turned on. After the energy converter receives the high-frequency alternating current signal generated by the ultrasonic generator, it generates ultrasonic waves to digest the smelting slag, and the magnetic stirrer continuously stirs to accelerate the mixing of the metallurgical slag and the composite digestion solution.

[0060] Exemplarily, the cooling tank comprises a stainless steel tank filled with cold water, and a container containing the eutectic is placed in the cooling tank for rapid cooling.

[0061] The leaching tank includes an ultrasonic generator and an energy converter, and the functions of the ultrasonic generator and the energy converter are as described above;

[0062] Exemplarily, the cooling leaching tank includes a stainless steel tank, an ultrasonic generator and an energy converter. After the container containing the eutectic is cooled, the leachate is added thereto and transferred to the stainless steel tank. The ultrasonic generator is turned on, and the energy converter generates ultrasonic waves after receiving the high-frequency alternating current signal generated by the ultrasonic generator, and the mixed solution of the eutectic and the leachate is emulsified and leached to fully leach the elements.

[0063] The liquid adding device includes a constant temperature liquid storage tank and a pipette pump, the constant temperature liquid storage tank is used to store test solutions of different temperatures, and the pipette pump is used to quantitatively absorb the test solutions; wherein, the constant temperature liquid storage tank may include multiple ones, which are used to store test solutions of different temperatures. By quantitatively adding test solutions of suitable temperatures, the temperature and total volume of the slag digestion solution finally obtained can reach preset values, thereby further saving digestion time.

[0064] The element detection device comprises an ICP-AES spectrometer, a multifunctional ion meter and a burette; wherein the ICP-AES spectrometer is used for the detection and analysis of calcium, magnesium, silicon, aluminum, iron, manganese, chromium, vanadium, titanium or copper elements, has a wide range of applications, a high degree of automation, a low detection limit and a short detection time, the multifunctional ion meter is used for the detection and analysis of fluorine element content, has a high detection accuracy and a short detection time, and the burette is used for the detection and analysis of ferrous elements, has a high detection accuracy and a short detection time.

[0065] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples without specifying specific conditions are usually based on the conditions recommended by the manufacturer.

[0066] Example 1

[0067] The contents of CaO, CaF2, MgO, Al2O3, SiO2, Fe and Mn in the refined slag during the steelmaking process are monitored and analyzed online. The test solutions used include: composite digestion solution 1: prepared by hydrochloric acid, nitric acid, perchloric acid, citric acid, tartaric acid, hydrofluoric acid, methanol and water in a volume ratio of 10:10:5:2:1:5:2:65; composite digestion solution 2: prepared by hydrochloric acid, nitric acid, perchloric acid, citric acid, tartaric acid, methanol and water in a volume ratio of 10:10:5:2:1:2:70; internal standard solution: 0.1% yttrium nitrate solution; ionic strength agent: a composite solution containing 30% sodium citrate and 10% potassium chloride. The following steps are included:

[0068] 1.1. Use standard products or reference reagents to prepare standard solutions at each mass concentration point of the ICP-AES spectrometer working curve. Compare the matrix of the refined slag measurement test solution, perform basic matching on the standard solutions, select appropriate analysis lines, and establish standard working curves for calcium, magnesium, aluminum, silicon, iron and manganese elements respectively; use sodium fluoride to prepare standard solutions of fluorine at five different mass concentration points, adjust the ionic strength and pH to 6.5, use a multifunctional ion meter and a fluorine electrode to measure the standard solutions, and draw a standard working curve for fluorine; adjust the ICP-AES spectrometer and the multifunctional ion meter to the injection state;

[0069] 1.2. Take samples from the smelting furnace, put them into sealed metal cans, and transport them to the testing laboratory through a special sample delivery air duct. Grind the refined slag with a vibration mill, weigh 0.2g (accurate to 0.1mg) of the ground refined slag sample and put it into beaker 1 containing 150mL of composite digestion solution 1, and weigh 0.5g (accurate to 0.1mg) of the ground refined slag sample and put it into beaker 2 containing 150mL of composite digestion solution 2;

[0070] 1.3. Place beaker 1 and beaker 2 in a digestion tank, turn on the ultrasonic generator and magnetic stirrer, digest for 60 seconds, then add 10 mL of internal standard solution and 90 mL of distilled water to beaker 1 to obtain slag digestion solution 1, and add 100 mL of distilled water to beaker 2 to obtain slag digestion solution 2;

[0071] 1.4. Add 30 mL of ionic strength agent and 30 mL of distilled water into a volumetric flask, add two drops of phenol red reagent, take 5 mL of slag digestion solution 2 and place it into a volumetric flask, use sodium hydroxide and hydrochloric acid to adjust the solution from red to yellow, then add one drop of hydrochloric acid in excess, add water to make up to 100 mL, and obtain test solution 2;

[0072] 1.5. Place the slag digestion solution 1 directly on the ICP-AES spectrometer for analysis, and analyze the test solution 2 using the fluorine electrode in the multifunctional ion meter;

[0073] 1.6. The analysis results of calcium, magnesium, aluminum, silicon, iron and manganese can be directly read from the ICP-AES spectrometer. Calcium is expressed as a single element W. Ca The fluorine element is obtained from the result of the multifunctional ion meter, and the calcium fluoride monitoring result is calculated by formula (1):

[0074] W CaF2 =W F ×78 / 38; (1)

[0075] The calcium oxide content is calculated by formula (2):

[0076] W CaO =(W Ca -W CaF2 ×40 / 78)×56: (2).

[0077] The test results are compared with the given values ​​of YSBC13836-96, as shown in Table 1:

[0078] Table 1 Refined slag analysis results (w%)

[0079]

[0080] It took 7 minutes and 30 seconds from sampling to obtaining the test results.

[0081] Example 2

[0082] This example uses the same analysis method as Example 1, except that the GSBH42009-94 blast furnace slag standard sample is analyzed. The test analysis results are shown in Table 2:

[0083] Table 2 Accuracy test of GSBH42009-94 blast furnace slag standard sample

[0084]

[0085] Example 3

[0086] This example adopts the same analysis method as Example 1, except that the GBW01707 converter slag standard sample is analyzed. The test analysis results are shown in Table 3:

[0087] Table 3 Accuracy test of GBW 01707 converter slag standard sample

[0088]

[0089]

[0090] It can be seen from Tables 1, 2 and 3 that the online monitoring and analysis method for metallurgical slag provided by the embodiment of the present invention can obtain accurate detection results, has the remarkable characteristics of high accuracy, and is short in time, taking into account both timeliness and accuracy; in addition, the online monitoring and analysis method for metallurgical slag provided by the embodiment of the present invention performs detection and analysis through the basic principle of quantitative analysis, and the obtained detection data has metrological traceability.

[0091] Figure 2 The method and device for online monitoring and analysis of metallurgical slag provided by the present invention are used to online monitor and analyze the operation status of refined slag in the steelmaking process.

[0092] like Figure 2 As shown, on April 16, 2021, the ingot shape was 67t and the sampling time was the refined slag after alloying. The analysis showed that the CaO content was 63.45%, the CaF2 content was 8.57%, the MgO content was 3.44%, the Al2O3 content was 2.16%, the SiO2 content was 18.78%, the Fe content was 0.26%, and the Mn content was 0.03%; on July 13, 2021, the ingot shape was 185t and the sampling time was the refined slag before steelmaking, and the analysis showed that the CaO content was 50.21%, the CaF2 content was 10.07%, the MgO content was 9.48%, the Al2O3 content was 1.46%, the SiO2 content was 27.93%, the Fe content was 0.44%, and the Mn content was 0.03%; through the online monitoring and analysis method and device for metallurgical slag, the situation of the refined slag can be understood in real time and accurately, so as to make timely adjustments.

[0093] Although the disclosure is disclosed as above, the protection scope of the disclosure is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims

1. A method for online monitoring and analysis of metallurgical slag, It is characterized in that Based on an online monitoring and analysis system for metallurgical slag, the system includes a digestion tank and an element detection device; Wherein, the digestion tank comprises a stainless steel tank, an ultrasonic generator, an energy converter and a magnetic stirrer, and the digestion tank is used to digest the metallurgical slag by ultrasonic waves; The element detection device is used to detect the element content in the slag digestion solution; The method comprises the following steps: Step S1, digesting the metallurgical slag by a normal temperature digestion method to obtain a slag digestion solution; wherein the normal temperature digestion method adopts a "composite digestion solution + ultrasonic" digestion method to obtain an acidic digestion solution of the slag sample; The room temperature digestion method comprises: grinding the metallurgical slag and mixing it with a composite digestion solution, placing it in ultrasound for 30-120s to obtain the slag digestion solution; the composite digestion solution is prepared by compounding hydrochloric acid, nitric acid, perchloric acid, citric acid, tartaric acid, hydrofluoric acid, methanol and water in a volume ratio of 10:10:5:2:1:5:2:65, or by compounding hydrochloric acid, nitric acid, perchloric acid, citric acid, tartaric acid, methanol and water in a volume ratio of 10:10:5:2:1:2:70; Step S2, analyzing the slag digestion solution by at least one of ICP spectroscopy, electrode method and titration analysis, and obtaining the element content in the metallurgical slag by using a pre-established and run element standard working curve.

2. The on-line monitoring and analysis method for metallurgical slag according to claim 1, It is characterized in that In step S2, an element standard working curve pre-established and run by ICP spectroscopy is used to complete the online analysis of multiple elements in metallurgical slag within 1-2 minutes. The ICP spectroscopy includes using an ICP-AES spectrometer to detect the content of calcium, magnesium, silicon, aluminum, iron, manganese, chromium, vanadium, titanium, phosphorus, sulfur or copper elements in the slag digestion solution.

3. The on-line monitoring and analysis method for metallurgical slag according to claim 1, It is characterized in that In the step S2, the fluorine element standard working curve pre-established and run by the electrode method is used to complete the online analysis of the fluorine element in the metallurgical slag within 1-2 minutes. The electrode method includes using a multifunctional ion meter to detect the content of fluorine element in the slag digestion solution.

4. The on-line monitoring and analysis method for metallurgical slag according to claim 1, It is characterized in that The element standard working curve includes at least one of a calcium standard working curve, a magnesium standard working curve, a silicon standard working curve, an aluminum standard working curve, an iron standard working curve, a manganese standard working curve, a chromium standard working curve, a vanadium standard working curve, a titanium standard working curve, a copper standard working curve, a fluorine standard working curve, a sulfur standard working curve, a phosphorus standard working curve and a ferrous standard working curve.

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