Method for detecting content of phosphorus in phosphogypsum

Abstract

The invention provides a method for detecting the content of phosphorus in ardealite, which comprises the following steps: A) adding hydroxypropyl methyl cellulose and a solvent into an ardealite sample to be detected, and grinding and tabletting to obtain a treated sample to be detected; b) determining the truth value of the standard phosphogypsum sample; the method comprises the following steps: detecting a standard ardealite sample with known concentration by adopting an X-ray fluorescence spectrometer, and establishing a standard curve according to the concentration and fluorescence intensity; and C) detecting a phosphogypsum sample to be detected by using the X fluorescence spectrometer to obtain a fluorescence intensity value, and calculating the phosphorus content according to the established standard curve. The method has the advantages of being high in automation degree, high in analysis speed, accurate and reliable in data, energy-saving, environment-friendly and the like; unmanned and nondestructive detection of the phosphorus content in the phosphogypsum is basically realized, and an efficient solution is provided for quality control in the phosphorus chemical industry.

Description

Technical Field

[0001] The present invention relates to the technical field of detection methods, and in particular to a method for detecting phosphorus content in phosphogypsum. Background Art

[0002] Phosphoric acid production processes are divided into wet and thermal processes, with the sulfuric acid wet process being the most prevalent. The wet process generates a large amount of phosphogypsum solid waste. According to statistics, every ton of phosphoric acid produced in the wet process generates 4-5 tons of phosphogypsum. Because phosphogypsum's primary component is calcium sulfate dihydrate, with a concentration exceeding 85%, it is a potential resource for replacing natural gypsum. Phosphogypsum has shown potential in building material substitution, chemical raw material recycling, soil improvement, and environmental remediation, but production and disposal are far from balanced. The phosphorus chemical industry is constantly exploring new pathways for phosphogypsum disposal. The decomposition of phosphogypsum to produce sulfuric acid and cement is a key approach to its comprehensive utilization. Substantial breakthroughs have been made in phosphogypsum as a calcium supplement for cement. However, impurities in phosphogypsum, particularly phosphorus content, are crucial for determining whether the physical properties of clinker and cement meet early strength requirements.

[0003] Currently, the main methods used to determine phosphorus content in phosphogypsum samples include quinoline gravimetric analysis, quinoline volumetric analysis, and vanadium molybdenum yellow dual-wavelength photometry. These methods all require cumbersome pretreatment, consume environmentally unfriendly chemical reagents, are time-consuming, and are susceptible to significant human influence, making them unsuitable for high-load production operations.

[0004] Compared with traditional methods, X-ray fluorescence analysis offers advantages such as rapid analysis, simple sample preparation, excellent stability and precision, and non-destructive testing. Currently, there is no research on X-ray fluorescence analysis of phosphorus content in phosphogypsum. This patent establishes a rapid analytical method for detecting phosphorus content in phosphogypsum based on a fully automated sampling system combined with X-ray fluorescence. Summary of the Invention

[0005] In view of this, the technical problem to be solved by the present invention is to provide a method for detecting the phosphorus content in phosphogypsum. The detection method provided by the present invention is simple, highly automated and produces accurate results.

[0006] The present invention provides a method for detecting the phosphorus content in phosphogypsum, comprising the following steps:

[0007] A) adding hydroxypropyl methylcellulose and a solvent to the phosphogypsum sample to be tested and grinding and tableting to obtain the treated sample to be tested;

[0008] B) determining the true value of a standard phosphogypsum sample; testing a standard phosphogypsum sample of known concentration using an X-ray fluorescence spectrometer, and establishing a standard curve based on the concentration and fluorescence intensity;

[0009] C) The phosphogypsum sample to be tested is tested using an X-ray fluorescence spectrometer to obtain a fluorescence intensity value, and the phosphorus content is calculated based on the established standard curve.

[0010] In some specific embodiments, the mass ratio of the phosphogypsum sample to be tested and hydroxypropyl methylcellulose in step A) is (10-30): (1.5-4.5).

[0011] In some specific embodiments, the solvent in step A) is methanol; the time for adding methanol is 20 to 40 seconds; and the flow rate of methanol is 0.04 mL / s.

[0012] In some specific embodiments, the grinding time in step A) is 1 to 2.5 min; and the grinding speed is 750 to 950 r / min.

[0013] In some specific embodiments, the tableting parameters in step A) include:

[0014] The mass ratio of the phosphogypsum sample to be tested and boric acid is (4-5):(14-15); the tableting time is maintained at 10s, and the tableting pressure is maintained at 40N.

[0015] In some specific embodiments, the X-ray fluorescence spectrometer detection parameters include:

[0016] Spectral line Kα1,2, crystal PE, measurement time 10s, PHD25-75, collimator 300μm, voltage 40kV, current 60mA, detection angle 89.4462°, energy 2.01keV.

[0017] In some specific implementations, the calculation formula is as follows:

[0018] y=13.7404x+0.7925;

[0019] Where y is the X-ray fluorescence absorption intensity; x is the percentage of P2O5 in phosphogypsum; 13.7404 is the slope; 0.7925 is the intercept; and its linear range is 0.326-1.283%.

[0020] In some specific embodiments, the method for determining the true value of the standard phosphogypsum sample is: using the quinoline phosphomolybdate weight method for total P2O5 determination.

[0021] In some specific embodiments, the introduction of the phosphogypsum sample to be tested includes remote automatic sampling or manual introduction.

[0022] In some specific embodiments, the detection limit is 0.08 and the quantification limit is 0.26.

[0023] Compared to the prior art, the present invention provides a method for detecting phosphorus content in phosphogypsum, comprising the following steps: A) adding hydroxypropyl methylcellulose and a solvent to a phosphogypsum sample to be tested, grinding and tableting the sample to obtain a treated sample; B) determining the true value of a standard phosphogypsum sample; testing a standard phosphogypsum sample of known concentration using an X-ray fluorescence spectrometer, and establishing a standard curve based on the concentration and fluorescence intensity; C) testing the phosphogypsum sample to be tested using an X-ray fluorescence spectrometer to obtain a fluorescence intensity value, and calculating the phosphorus content based on the established standard curve. The method of the present invention has the advantages of a high degree of automation, fast analysis speed, accurate and reliable data, energy conservation and environmental protection; it essentially achieves unmanned, non-destructive testing of phosphorus content in phosphogypsum, providing an efficient solution for quality control in the phosphorus chemical industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is the X-ray fluorescence P2O5 standard curve. DETAILED DESCRIPTION

[0025] The present invention provides a method for detecting the phosphorus content in phosphogypsum. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve it. It should be pointed out in particular that all similar replacements and modifications are obvious to those skilled in the art and they all fall within the scope of protection of the present invention. The method and application of the present invention have been described through preferred embodiments. Relevant personnel can obviously modify or appropriately change and combine the method and application of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0026] The present invention provides an analysis method for rapidly detecting the phosphorus content in phosphogypsum using a fully automated system combined with X-ray fluorescence, thereby achieving the advantages of high automation, fast analysis speed, accurate and reliable data, energy saving and environmental protection, and realizing unmanned and non-destructive detection of the phosphorus content in phosphogypsum.

[0027] The present invention provides a method for detecting the phosphorus content in phosphogypsum, comprising the following steps:

[0028] A) adding hydroxypropyl methylcellulose and a solvent to the phosphogypsum sample to be tested and grinding and tableting to obtain the treated sample to be tested;

[0029] B) determining the true value of a standard phosphogypsum sample; testing a standard phosphogypsum sample of known concentration using an X-ray fluorescence spectrometer, and establishing a standard curve based on the concentration and fluorescence intensity;

[0030] C) The phosphogypsum sample to be tested is tested using an X-ray fluorescence spectrometer to obtain a fluorescence intensity value, and the phosphorus content is calculated based on the established standard curve.

[0031] The present invention first determines the true value of a standard phosphogypsum sample.

[0032] In some specific embodiments, the method for determining the true value of the standard phosphogypsum sample is: using the quinoline phosphomolybdate weight method for total P2O5 determination.

[0033] The present invention is not limited to the above method, and it can be well known to those skilled in the art.

[0034] The present invention adopts a method of averaging multiple measurements to make the true value determination result more accurate. The present invention preferably adopts a method of averaging the P2O5 results of 5 to 10 times of testing the same batch of phosphogypsum.

[0035] The average value of the results of 5 to 10 parallel manual tests (phosphomolybdic acid quinoline weight method for total P2O5 determination in JC / T 2073-2011) is the true value of the test sample.

[0036] Standard phosphogypsum samples of known concentration were detected using an X-ray fluorescence spectrometer, and a standard curve was established based on the concentration and fluorescence intensity.

[0037] Hydroxypropyl methylcellulose and a solvent are added to the phosphogypsum sample to be tested, and the sample is ground and tableted to obtain a processed sample to be tested.

[0038] In some specific embodiments, the mass ratio of the phosphogypsum sample to be tested and hydroxypropyl methylcellulose is (10-30): (1.5-4.5); more preferably (20-30): (3.5-4.5)

[0039] The mass ratio of the phosphogypsum sample to be tested to the hydroxypropyl methylcellulose of the present invention can be 10:3.5, 15:3.5, 25:3.5, 30:3.5; or 25:1.5, 25:2.5, 25:3.5, 25:4.5.

[0040] The present invention has found through research that when the mass ratio of the phosphogypsum sample to be tested and hydroxypropyl methylcellulose is 25:3.5, the linear effect is optimal.

[0041] In some specific embodiments, the solvent is methanol, and the time for adding methanol is 20 to 40 seconds, specifically 20, 30, or 40 seconds. The inventors have found that the linear effect is best when the time is 20 seconds.

[0042] The flow rate of methanol was 0.04 mL / s.

[0043] In some specific embodiments, the grinding time is 1 to 2.5 min; preferably 1.5 to 2.5 min; specifically 1, 1.5, 2, or 2.5 min.

[0044] The inventors found that the linear effect was best when grinding for 2 minutes.

[0045] The grinding speed of the present invention is 750-950 r / min, preferably 850-950 r / min, specifically 650, 750, 850, 950 r / min, or a range between any two of the above.

[0046] The inventors found that the linearity was optimal when the grinding speed was 850 r / min.

[0047] In some specific embodiments, the tableting parameters in step A) include: boric acid coating;

[0048] The mass ratio of the phosphogypsum sample to be tested and boric acid is (4-5):(14-15); the tableting time is maintained at 10s, and the tableting pressure is maintained at 40N.

[0049] The present inventors have found that under the above tableting parameters, the measurement results are accurate, while under non-above tableting parameters, the effect is poor.

[0050] Standard phosphogypsum samples with known concentrations were tested using an X-ray fluorescence spectrometer, and a standard curve was established based on the concentration and fluorescence intensity.

[0051] The phosphogypsum sample to be tested is detected by an X-ray fluorescence spectrometer to obtain the fluorescence intensity value, and the phosphorus content is calculated according to the established standard curve.

[0052] In some specific embodiments, the X-ray fluorescence spectrometer detection parameters include:

[0053] Spectral line Kα1,2, crystal PE, measurement time 10s, PHD25-75, collimator 300μm, voltage 40kV, current 60mA, detection angle 89.4462°, energy 2.01keV.

[0054] In some specific implementations, the calculation formula is as follows:

[0055] y=13.7404x+0.7925;

[0056] Where y is the X-ray fluorescence absorption intensity; x is the percentage of P2O5 in phosphogypsum; 13.7404 is the slope; 0.7925 is the intercept; and its linear range is 0.326-1.283%.

[0057] In some specific embodiments, the introduction of the phosphogypsum sample to be tested includes remote automatic sampling or manual introduction. Specifically, the sample introduction can be: ① remote automatic sampling (an automatic sampling port is provided in the dried storage bin, and the sample is automatically introduced to the automated system sample station by the remote system); ② manual introduction (when the remote automatic sampling fails or a temporary sample needs to be analyzed (to establish a standard curve), manual introduction is input into the sample station).

[0058] The remote automatic sampling process of the present invention can preferably be:

[0059] An automatic material taking port is set up in the storage bin after drying → sampling (intermittent grabbing with the help of the mechanical arm's telescopic hand) → screening (the hopper at the bottom of the sampler can screen the sample) → entering the conveying system (through a closed pipe and a power fan) and transporting it to the receiving station in the analysis room → the mechanical arm grabs the sample cup from the sample table and takes it to the receiving station to retain the sample (according to the material density, the sample volume is set to reversely infer the material mass) → After the analysis system receives the material, the mechanical arm grabs the sample and enters the grinder, adds grinding aids according to the program, and grinds it together with the material → transports it to the tablet press for tableting → transports it to the fluorescence system → automatically performs detection and analysis according to the fluorescence setting parameters.

[0060] The manual sampling process of the present invention can preferably be:

[0061] Manually introduce the sample input into the sample table, weigh a certain amount of material and put it on the sample table → After the analysis system receives the material, the robotic arm grabs the sample and puts it into the grinder, adds grinding aid according to the program, and grinds it together with the material → transports it to the tablet press for tableting → transports it to the fluorescence system → automatically detects and analyzes it according to the fluorescence setting parameters.

[0062] In some specific embodiments, the detection limit is 0.08 and the quantification limit is 0.26.

[0063] The present invention provides a method for detecting the phosphorus content in phosphogypsum, comprising the following steps: A) adding hydroxypropyl methylcellulose and a solvent to a phosphogypsum sample to be tested, grinding and tableting the sample to obtain a treated sample to be tested; B) determining the true value of a standard phosphogypsum sample; testing a standard phosphogypsum sample of known concentration using an X-ray fluorescence spectrometer, and establishing a standard curve based on the concentration and fluorescence intensity; C) testing the phosphogypsum sample to be tested using an X-ray fluorescence spectrometer to obtain a fluorescence intensity value, and calculating the phosphorus content based on the established standard curve. The method of the present invention has the advantages of a high degree of automation, fast analysis speed, accurate and reliable data, energy conservation and environmental protection, and substantially realizes unmanned, non-destructive testing of phosphorus content in phosphogypsum, providing an efficient solution for quality control in the phosphorus chemical industry.

[0064] It should be understood that the expression "one or more of" includes individually each of the items recited after the expression and various combinations of two or more of the recited items, unless otherwise apparent from the context and usage. The expression "and / or" in conjunction with three or more recited items should be understood to have the same meaning, unless otherwise apparent from the context.

[0065] The terms "comprising", "having" or "containing", including their grammatical synonyms, should generally be understood as open and non-restrictive, e.g., not excluding other unrecited elements or steps, unless otherwise specifically stated or understood from the context.

[0066] In this application, the term "and / or" describes the association relationship between associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural.

[0067] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items.

[0068] It should be understood that the order of steps or the order in which certain actions are performed are not important as long as the present invention remains operable. Additionally, two or more steps or actions may be performed simultaneously.

[0069] The use of any and all examples or exemplary language, such as "such as" or "including," herein is intended merely to better illustrate the invention and does not limit the scope of the invention unless otherwise claimed. No language in this specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0070] In addition, the numerical ranges and parameters used to define the present invention are approximate values. The relevant numerical values ​​in the specific examples have been presented as accurately as possible. However, any numerical value inherently inevitably contains standard deviations due to individual testing methods. Therefore, unless otherwise expressly stated, all ranges, amounts, values, and percentages used in this disclosure should be understood to be modified by the word "about." As used herein, "about" generally means that the actual value is within plus or minus 10%, 5%, 1%, or 0.5% of a specified value or range.

[0071] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. Some or all of the steps can be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0072] Some cases are described in the embodiments and comparative examples of the present invention, wherein the embodiments illustrate certain implementations of the present invention. However, this does not mean that the effects of the present invention can only be achieved in these cases.

[0073] In order to further illustrate the present invention, the lithium ion battery positive electrode material provided by the present invention is described in detail below with reference to the examples.

[0074] Example 1

[0075] The true value of the standard phosphogypsum sample was determined. For the powder tableting method, the matrix effect, particle size and component composition are the main factors leading to analytical errors. In order to eliminate the influence of the matrix effect, samples were collected over a long period of time and the phosphogypsum samples produced by Wengfu (Group) Co., Ltd. were used. The average value of the results of 5 parallel manual tests (phosphomolybdic acid quinoline weight method for total P205 determination according to JC / T 2073-2011) was used as the true value of the standard.

[0076]

[0077] Pre-tabletting treatment is a crucial step in fluorescence detection. Its quality directly affects the accuracy and reliability of the test results. In order to improve sample homogeneity, optimize sample surface properties, and eliminate matrix effects, it is necessary to explore the methods of grinding and tableting. For example, hydroxypropyl methylcellulose and solvent are added to the phosphogypsum sample to be tested, and then ground and tableted to obtain the treated sample to be tested.

[0078] Standard phosphogypsum samples with known concentrations were tested using an X-ray fluorescence spectrometer, and a standard curve was established based on the concentration and fluorescence intensity.

[0079] The phosphogypsum sample to be tested is detected by an X-ray fluorescence spectrometer to obtain the fluorescence intensity value, and the phosphorus content is calculated according to the established standard curve.

[0080] Weigh 10 g of reference phosphogypsum onto the sample stand, set the system to add 3.5 g of methyl fiber, the methanol flow rate to 0.04 mL / s, the addition time to 20 s, the grinding time to 2 min, and the grinding speed to 850 r / min.

[0081] Example 2

[0082] 25g of reference phosphogypsum was placed on the sample stand, the system was set to add 3.5g of methyl fiber, the methanol flow rate was set to 0.04mL / s, the addition time was set to 20s, the grinding time was maintained at 2min, and the grinding speed was maintained at 850r / min.

[0083] Example 3

[0084] Weigh 25g of the reference substance phosphogypsum onto the sample table, set the system to add 4.5g of hydroxypropyl methylcellulose, add methanol for 20s, keep the grinding time at 2min, and keep the grinding speed at 850r / min.

[0085] Example 4

[0086] Weigh 25g of the reference substance phosphogypsum onto the sample holder, set the system to add 3.5g of hydroxypropyl methylcellulose, add methanol for 40s, maintain the tableting time for 10s, and maintain the tableting pressure at 40N.

[0087] Example 5

[0088] Weigh 25g of the reference substance phosphogypsum onto the sample holder, set the system to add 3.5g of hydroxypropyl methylcellulose, add methanol for 20s, keep the grinding time at 1min, and keep the grinding speed at 850r / min.

[0089] Example 6

[0090] Weigh 25g of reference phosphogypsum onto the sample stand, set the system to add 3.5g of methyl fiber, add methanol for 20s, keep the grinding time at 2min, and keep the grinding speed at 650r / min.

[0091] Set specific working parameters. The working parameters of XRF instrument for determination of phosphorus in phosphogypsum are shown in Table 1.

[0092] Table 1

[0093]

[0094]

[0095] Calculate the phosphorus content in the sample: according to the following formula:

[0096] y=13.7404x+0.7925

[0097] Where y is the X-ray fluorescence absorption intensity; x is the P2O5 content in phosphogypsum; 13.7404 is the slope; 0.7925 is the intercept; and the linear range is 0.326-1.283%. When testing unknown samples, the P2O5 content in phosphogypsum can be calculated based on the X-ray fluorescence absorption intensity.

[0098] The linear relationship R2 results of the standard curves established between the test sample and the fluorescence intensity in Examples 1, 2, 3, 4, 5, and 6 are shown in Table 2.

[0099] Table 2

[0100] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 <![CDATA[R 2 =0.9877]]> <![CDATA[R 2 =0.9984]]> <![CDATA[R 2 =0.9902]]> <![CDATA[R 2 =0.9859]]> <![CDATA[R 2 =0.9921]]> <![CDATA[R 2 =0.9895]]>

[0101] As shown in Table 2, the optimal parameters for sample pretreatment are 25 g of phosphogypsum, 3.5 g of hydroxypropyl methylcellulose, 20 s of methanol addition time, 2 min of grinding time, and 850 r / min of grinding speed.

[0102] Example 7

[0103] The standard curve of the test sample was prepared according to the optimal parameters of sample pretreatment. The relationship between its P2O5 content and fluorescence intensity is as follows, see Table 3.

[0104] Table 3

[0105]

[0106] Under optimal analytical parameters, the linear relationship between the P2O5 content of phosphogypsum and X-ray fluorescence absorption intensity is as follows: y = 13.7404x + 0.7925, where y is the X-ray fluorescence absorption intensity; x is the P2O5 content of phosphogypsum; 13.7404 is the slope; and 0.7925 is the intercept. The linear range is 0.326-1.283%. When testing unknown samples, the P2O5 content in the phosphogypsum can be calculated based on the X-ray fluorescence absorption intensity.

[0107] Example 8

[0108] The precision determination was carried out by analyzing and testing the dry basis of phosphogypsum produced in the same batch according to Example 7, and statistical analysis was performed on the test results of 10 tablet analyses, and the mean value, standard deviation and RSD were examined respectively.

[0109] Table 4 Precision statistical results

[0110]

[0111] As shown in Table 4, the P2O5 results of the same batch of phosphogypsum were tested 10 times, with an average of 0.86%, a standard deviation of 0.01%, and an RSD of 1.20% < 2%, indicating that the fluorescence curve method established in this paper has good precision and can meet the production control requirements.

[0112] Example 9

[0113] Accuracy determination was carried out by analyzing and testing three different control phosphogypsum dry bases (TP contents were 0.65, 0.75, and 0.82%, respectively) according to Example 7. The nine test results were statistically analyzed to examine their mean values, standard deviations, and RSDs.

[0114] Table 5 Accuracy statistics

[0115]

[0116]

[0117] The accuracy of the new method was tested on three standard control phosphogypsums. Table 5 shows that the accuracy of the new method is good, and the method is suitable for the analysis of P2O5 content in phosphogypsum.

[0118] Example 10

[0119] Spiked recovery was determined using samples from the same production batch as the test sample and phosphogypsum with P₂O₅ contents of 0.65%, 0.75%, and 0.82% as the reference. Since 25 g of phosphogypsum was used during the grinding process, the reference sample was added to 25 g of phosphogypsum of known concentration and thoroughly mixed. Then, another 25 g of phosphogypsum was weighed and ground.

[0120] Table 6 Statistical results of spike recovery

[0121]

[0122] The fully automatic system combined with fluorescence rapid detection of phosphorus content in phosphogypsum established in this study was subjected to a spike recovery test. As shown in Table 6, the spike recovery rate of the new method was between (93.3% and 102.9%), which was a good recovery rate.

[0123] Example 11

[0124] Detection limit and quantification limit determination, take 20 phosphogypsum samples, analyze and detect according to Example 7. The average value of the test results of 20 samples is used The detection limit and quantification limit of the established P2O5 analysis method were calculated using the standard deviation (σ).

[0125] Table 7 Statistical results of detection limit and quantification limit

[0126]

[0127] The fully automated system established in this study was combined with an X-ray fluorescence analysis method to rapidly determine the phosphorus content in phosphogypsum. Twenty phosphogypsum samples produced in the same batch were measured. The test results of the 20 samples, as well as their means and standard deviations, were calculated using this method and are shown in Table 7.

[0128] Detection limit:

[0129] Limit of Quantitation:

[0130] The detection limit and quantification limit were 0.08 and 0.26, respectively.

[0131] Example 12

[0132] To further prove the feasibility of the new method, the new method was compared with the volumetric method in the "Determination of phosphorus and fluorine in phosphogypsum" JC / T 2073-2011 for the accuracy of the standard sample.

[0133] Table 8 Test results of accuracy and repeatability

[0134]

[0135]

[0136] Table 8 shows that there is no significant difference between the results of the new method and the volumetric method. The new method can achieve a single-sample testing time of less than 10 minutes, while the volumetric analysis method takes >120 minutes. Furthermore, the new method essentially enables unmanned, nondestructive testing of phosphorus content in phosphogypsum, providing a highly efficient solution for quality control in the phosphorus chemical industry.

[0137] Verification Example

[0138] (1) Influence of phosphogypsum dosage

[0139] Weigh 10, 15, 25, and 30 g of reference phosphogypsum onto the sample stand. Set the system to add 3.5 g of methyl fiber, the methanol flow rate to 0.04 mL / s, the addition time to 20 s, the grinding time to 2 min, and the grinding speed to 850 r / min.

[0140]

[0141] When the dosage of phosphogypsum is 25g, the linearity is the best.

[0142] (2) Effect of the dosage of hydroxypropyl methylcellulose

[0143] Weigh 25g of the reference substance phosphogypsum onto the sample table, set the system to add 1.5, 2.5, 3.5, and 4.5g of hydroxypropyl methylcellulose, the methanol addition time is 20s, the grinding time is maintained at 2min, and the grinding speed is maintained at 850r / min.

[0144]

[0145] The linearity was optimal when the amount of methylcellulose was 3.5 g.

[0146] (3) Influence of methanol dosage

[0147] Weigh 25g of the reference substance phosphogypsum onto the sample holder, set the system to add 3.5g of hydroxypropyl methylcellulose, the methanol addition time to 10, 20, 30, and 40s, the tableting time to 10s, and the tableting pressure to 40N.

[0148]

[0149] The linearity is best when the methanol addition time is 20s.

[0150] (4) Influence of grinding time

[0151] Weigh 25g of the reference substance phosphogypsum onto the sample table, set the system to add 3.5g of hydroxypropyl methylcellulose, add methanol for 20s, keep the grinding time at 1, 1.5, 2, and 2.5min, and keep the grinding speed at 850r / min.

[0152]

[0153]

[0154] The linear equation is optimal when the grinding time is 2 min.

[0155] (5) Influence of grinding speed

[0156] Weigh 25g of reference phosphogypsum onto the sample stand, set the system to add 3.5g of methyl fiber, add methanol for 20s, keep the grinding time at 2min, and keep the grinding speed at 650, 750, 850, and 950r / min.

[0157]

[0158] The linearity is best when the grinding speed is 850 r / min.

[0159] (6) Influence of fluorescence parameter integration measurement time

[0160] Weigh 25g of the reference phosphogypsum onto the sample holder. Set the system to add 3.5g of methylcellulose, add methanol for 20 seconds, grind for 2 minutes, and maintain a grinding speed of 850 rpm. After tableting, a conveyor belt transports the sample to the fluorescence detection window. The fluorescence parameter integration measurement time is adjusted, while other parameters remain unchanged. Fluorescence integration measurement times are set to 8, 10, 12, and 14 seconds.

[0161]

[0162] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for detecting phosphorus content in phosphogypsum, characterized in that: The steps include: A) adding hydroxypropyl methylcellulose and a solvent to the phosphogypsum sample to be tested and grinding and tableting to obtain the treated sample to be tested; B) determining the true value of a standard phosphogypsum sample; testing a standard phosphogypsum sample of known concentration using an X-ray fluorescence spectrometer, and establishing a standard curve based on the concentration and fluorescence intensity; C) The phosphogypsum sample to be tested is tested using an X-ray fluorescence spectrometer to obtain a fluorescence intensity value, and the phosphorus content is calculated based on the established standard curve.

2. The detection method according to claim 1, wherein In step A), the mass ratio of the phosphogypsum sample to be tested to hydroxypropyl methylcellulose is (10-30): (1.5-4.5).

3. The detection method according to claim 1, wherein In step A), the solvent is methanol; the time for adding methanol is 20 to 40 seconds; and the flow rate of methanol is 0.04 mL / s.

4. The detection method according to claim 1, wherein The grinding time of step A) is 1 to 2.5 minutes; and the grinding speed is 750 to 950 r / min.

5. The detection method according to claim 1, wherein Step A) the tableting parameters include: The mass ratio of the phosphogypsum sample to be tested and boric acid is (4-5):(14-15); the tableting time is maintained at 10s, and the tableting pressure is maintained at 40N.

6. The detection method according to claim 1, characterized in that The X-ray fluorescence spectrometer detection parameters include: Spectral line Kα1,2, crystal PE, measurement time 10s, PHD25-75, collimator 300μm, voltage 40kV, current 60mA, detection angle 89.4462°, energy 2.01keV.

7. The detection method according to claim 1, characterized in that The calculation formula is as follows: y=13.7404x+0.7925; Where y is the X fluorescence absorption intensity; x is the percentage content of phosphogypsum P2O5; 13.7404 is the slope; The intercept is 0.7925; its linear range is 0.326~1.283%.

8. The detection method according to claim 1, wherein The method for determining the true value of the standard phosphogypsum sample is: using the quinoline phosphomolybdate weight method for total P2O5 determination.

9. The detection method according to claim 1, wherein The introduction of the phosphogypsum sample to be tested includes remote automatic sampling or manual introduction.

10. The detection method according to claim 1, characterized in that The detection limit was 0.08 and the quantification limit was 0.26.

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