Method for evaluating service life of ozone catalyst

Abstract

The invention relates to the field of catalyst life evaluation, and discloses a catalyst life evaluation method, which comprises: carrying out at least one gas-liquid backwashing on an ozone catalyst; wherein each time of gas-liquid backwashing comprises the following steps: sequentially carrying out gas washing, gas-liquid combined washing and liquid washing on the ozone catalyst; wherein the number of times of gas-liquid backwashing is i, and the service life of the ozone catalyst is in negative correlation with the compressive strength or particle size qualification degree after the ith gas-liquid backwashing. By adopting the method for evaluating the service life of the ozone catalyst, the cycle of evaluating the service life of the ozone catalyst is greatly shortened, the cost in the process of evaluating the service life of the catalyst is effectively reduced, and the accuracy of evaluating the service life of the ozone catalyst is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of catalyst lifetime evaluation, and more specifically, to a method for evaluating the lifetime of an ozone catalyst. Background Technology

[0002] Catalyst lifespan is a core indicator for evaluating catalyst performance. Currently, there is no commercially available method for evaluating the lifespan of ozone catalysts. The only method is to use actual wastewater treatment to determine the lifespan of ozone catalysts. This involves the catalyst operating continuously for a long time under actual working conditions, and the lifespan is determined based on the wastewater treatment effect and catalyst changes. This testing method is time-consuming and inefficient. Therefore, it is necessary to strengthen research on catalyst lifespan evaluation and screen out stable, efficient, and long-life catalysts, which is key to the large-scale application of catalysts. Summary of the Invention

[0003] The purpose of this invention is to overcome the problem of long evaluation time in the prior art and to provide a method for evaluating catalyst lifetime, which has the advantages of short evaluation time, wide applicability to catalysts, and high accuracy.

[0004] To achieve the above objectives, the present invention provides a method for evaluating the lifetime of an ozone catalyst, the method comprising: performing at least one gas-liquid backwash on the ozone catalyst;

[0005] The steps of each gas-liquid backwashing include: sequentially performing gas washing, combined gas-liquid washing, and liquid washing on the ozone catalyst;

[0006] The number of gas-liquid backwashes is i, and the service life of the ozone catalyst is negatively correlated with the compressive strength or particle size qualification after the i-th gas-liquid backwash.

[0007] Through the above technical solution, the present invention can achieve at least the following beneficial effects:

[0008] (1) The method for evaluating the lifespan of ozone catalysts using the present invention greatly shortens the evaluation cycle of ozone catalyst lifespan and effectively reduces the cost in the process of evaluating catalyst lifespan.

[0009] (2) The calculation method for the lifespan of the ozone catalyst of the present invention effectively improves the accuracy of the evaluation of the lifespan of the ozone catalyst.

[0010] (3) In this invention, under actual working conditions, the accuracy of the life evaluation method of this invention can be verified by knowing in advance the treatment life of a certain ozone catalyst for a specific wastewater; the life evaluation method of this invention can be used to predict the life of an unknown ozone catalyst for a specific wastewater. Attached Figure Description

[0011] Figure 1 This is a preferred embodiment of the ozone catalyst lifetime evaluation device of the present invention.

[0012] Explanation of reference numerals in the attached figures

[0013] 1-Backwash air inlet; 2-Backwash air distributor; 3-Backwash water inlet; 4-Backwash water distributor; 5-Catalyst bed; 6-Overflow weir; 7-Backwash drain; 8-Backwash exhaust port. Detailed Implementation

[0014] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0015] This invention provides a method for evaluating the lifetime of an ozone catalyst, the method comprising: performing at least one gas-liquid backwash on the ozone catalyst;

[0016] The steps of each gas-liquid backwashing include: sequentially performing gas washing, combined gas-liquid washing, and liquid washing on the ozone catalyst;

[0017] The number of gas-liquid backwashes is i, and the service life of the ozone catalyst is negatively correlated with the compressive strength or particle size qualification after the i-th gas-liquid backwash.

[0018] In this invention, preferably, the lifespan of the ozone catalyst is calculated as follows: Year, T represents the lifespan of the ozone catalyst, X i X represents the compressive strength or particle size conformity after the i-th gas-liquid backwash, where i is an integer from 1 to n; i The T value and X calculated when the compressive strength is... i The T-values ​​calculated for particle size compliance are compared, and the smaller one is taken as the lifespan of the ozone catalyst.

[0019] In a preferred embodiment of the present invention, the value of n in "i is an integer from 1 to n" is not particularly limited, as long as n≥1 is guaranteed. For example, the value of n can be 1-15 (for example, it can be any two values ​​formed by 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and the value within the range), preferably 2-10.

[0020] It is understandable that X in the formula i-1 X refers to the compressive strength or particle size conformity of the ozone catalyst after the (i-1)th gas-liquid backwash. When i = 1, Xi-1 This refers to the compressive strength or particle size compliance of ozone catalysts that have not undergone gas-liquid backwashing. Compressive strength (N / particle) refers to the ability of catalyst particles to resist external pressure without breaking or deforming; compressive strength is measured using a particle strength tester. Particle size compliance (%) refers to the percentage of catalyst particles within the acceptable particle size range; the test method is sieving.

[0021] In this invention, catalyst lifetime evaluation employs a combination of separate gas washing, gas-water backwashing, and separate water washing. By increasing the backwashing intensity, the catalyst is brought to a damaged state under extreme conditions, thus more closely reflecting the actual operating state of ozone catalysts. The backwashed catalyst is characterized and analyzed, with its compressive strength and particle size distribution measured. Calculations using the formula of this invention yield more reasonable and accurate results. This invention offers advantages such as simple operation, short processing time, and high efficiency.

[0022] In this invention, preferably, the gas source for gas scrubbing can be at least one of a blower, compressed air, and pressure swing adsorption.

[0023] In this invention, preferably, the conditions for gas scrubbing may include: a gas scrubbing intensity of 12-28 L·m -2 ·s -1 (For example, it can be 12 L·m -2 ·s -1 13 L·m -2 ·s -1 14 L·m -2 ·s -1 15L·m -2 ·s -1 16 L·m -2 ·s -1 17 L·m -2 ·s -1 18L·m -2 ·s -1 19 L·m -2 ·s -1 20L·m -2 ·s -1 21 L·m -2 ·s -1 22 L·m -2 ·s -1 23 L·m -2 ·s -1 24 L·m -2 ·s -1 25L·m -2 ·s -1 26 L·m -2 ·s -1 27 L·m-2 ·s -1 28 L·m -2 ·s -1 The range formed by any two values ​​in the range and the values ​​within that range are preferred to be 15-25 L·m. -2 ·s -1 The air washing time can be 4-12h (e.g., it can be any two values ​​formed by 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h, 12h and values ​​within that range), more preferably 5-10h; the air washing temperature can be 15-35℃ (e.g., it can be any two values ​​formed by 15℃, 16℃, 17℃, 18℃, 19℃, 20℃, 21℃, 22℃, 23℃, 24℃, 25℃, 26℃, 27℃, 28℃, 29℃, 30℃, 31℃, 32℃, 33℃, 34℃, 35℃ and values ​​within that range), more preferably 20-30℃.

[0024] In this invention, it can be understood that "L·m" -2 ·s -1 "" refers to the volume of fluid (gas or liquid) passing through a unit area per unit time during the gas washing or liquid washing process.

[0025] In this invention, preferably, the liquid used for gas-liquid combined washing and liquid washing can be a liquid commonly used in the art, such as at least one of water, brine, and circulating cooling water.

[0026] In this invention, preferably, the influent requirements for the gas-liquid combined washing and liquid washing may include: suspended solids (SS) ≤ 10 mg / L (e.g., any two values ​​from 2 mg / L, 4 mg / L, 6 mg / L, 8 mg / L, 10 mg / L, or values ​​within that range), hardness ≤ 300 mg / L (e.g., any two values ​​from 100 mg / L, 120 mg / L, 140 mg / L, 160 mg / L, 180 mg / L, 200 mg / L, 220 mg / L, 240 mg / L, 260 mg / L, 280 mg / L, 300 mg / L, or values ​​within that range), and COD (chemical oxygen demand) ≤ 20 mg / L (e.g., 5 mg / L, 10 mg / L, 12 mg / L). The requirements for the influent of the gas-liquid combined washing and liquid washing may include: suspended solids content ≤ 5 mg / L, hardness ≤ 250 mg / L, salt content ≤ 500 mg / L, COD ≤ 10 mg / L, and pH value 6.5-8. (For example, it can be any two values ​​from 100 mg / L, 200 mg / L, 400 mg / L, 600 mg / L, 800 mg / L, 1000 mg / L, forming a range and values ​​within that range).

[0027] In this invention, preferably, the conditions for the combined gas-liquid washing may include: a gas washing intensity of 10-20 L·m -2 ·s -1 (For example, it can be 10 L·m -2 ·s -1 11 L·m -2 ·s -1 12L·m -2 ·s -1 13 L·m -2 ·s -1 14 L·m -2 ·s -1 15L·m -2 ·s -1 16 L·m -2 ·s -1 17 L·m -2 ·s -1 18L·m -2 ·s -1 19 L·m -2 ·s -120L·m -2 ·s -1 The range formed by any two values ​​in the range and the values ​​within that range, more preferably, is 12-15 L·m -2 ·s -1 The washing strength can be 2-8 L·m. -2 ·s -1 (For example, it can be 2 L·m -2 ·s -1 3L·m -2 ·s -1 4L·m -2 ·s -1 5L·m -2 ·s -1 6L·m -2 ·s -1 7L·m -2 ·s -1 8L·m -2 ·s -1 The range formed by any two values ​​in the range and the values ​​within that range are preferred to be 4-6 L·m -2 ·s -1 The combined gas-liquid backwashing time can be 2-6 hours (e.g., any two values ​​from 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours, and 6 hours, or any value within that range), more preferably 3-5 hours; the combined gas-liquid backwashing temperature can be 15-35°C (e.g., any two values ​​from 15°C, 18°C, 20°C, 22°C, 25°C, 28°C, 30°C, 33°C, and 35°C, or any value within that range), more preferably 20-30°C.

[0028] In this invention, preferably, the conditions for liquid washing may include: a liquid washing intensity of 4-12 L·m -2 ·s -1 (For example, it can be 4 L·m -2 ·s -1 5L·m -2 ·s -1 6L·m -2 ·s -1 7L·m -2 ·s -1 8L·m -2 ·s -1 9L·m -2 ·s -1 10 L·m -2 ·s -1 11 L·m -2 ·s -1 12L·m-2 ·s -1 The range formed by any two values ​​in the range and the values ​​within the range, more preferably 5-10 L·m -2 ·s -1 The washing time can be 5-12h (for example, it can be any two values ​​formed by 5h, 6h, 7h, 8h, 9h, 10h, 11h, 12h and the values ​​within that range), more preferably 6-10h; the washing temperature can be 15-35℃ (for example, it can be any two values ​​formed by 15℃, 18℃, 20℃, 22℃, 25℃, 28℃, 30℃, 33℃, 35℃ and the values ​​within that range), more preferably 20-30℃.

[0029] In this invention, by controlling the washing intensity and washing time of gas washing, gas-liquid combined washing, and liquid washing, the loss of catalyst in actual application is simulated. The consumption of a catalyst for one year can be simulated in a short time, which greatly reduces the time for evaluating catalyst life. The catalyst required for production can be selected in a short time. Furthermore, by precisely controlling each washing condition, the accuracy of the catalyst life results is high.

[0030] In this invention, preferably, the method further includes: drying the catalyst after gas-liquid backwashing and then performing performance testing; wherein the drying temperature and time are sufficient to dry the catalyst after gas-liquid backwashing, for example, the drying time can be 200-400℃ (for example, it can be any two values ​​formed by 200℃, 210℃, 220℃, 230℃, 240℃, 250℃, 260℃, 270℃, 280℃, 290℃, 300℃, 310℃, 320℃, 330℃, 340℃, 350℃, 360℃, 370℃, 380℃, 390℃, 400℃, forming a range or values ​​within the range), and the drying time can be 2-5h (for example, it can be any two values ​​formed by 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, forming a range or values ​​within the range).

[0031] In a preferred embodiment of the present invention, there is no particular limitation on the ozone catalyst lifetime assessment device, as long as it can perform gas-liquid backwashing. For example, it can be an ozone catalyst lifetime assessment device with a main structure similar to a catalytic oxidation tower (e.g., Figure 1As shown in the figure, the ozone catalyst life evaluation device is provided with a backwash air inlet 1, a backwash water inlet 3, a backwash liquid outlet 7 and a backwash exhaust outlet 8 from bottom to top on the outside. The ozone catalyst life evaluation device is provided with a backwash air distributor 2, a backwash water distributor 4, a catalyst bed 5 and an overflow weir 6 from bottom to top on the inside. The backwash air inlet 1 is connected to the backwash air distributor 2, the backwash water inlet 3 is connected to the backwash water distributor 4, the backwash exhaust outlet 8 and the backwash liquid outlet 7 are located above the overflow weir 6, and the catalyst bed 5 is located between the overflow weir 6 and the backwash water distributor 4.

[0032] In a preferred embodiment of the present invention, the gas-liquid backwashing step may include:

[0033] S1. The gas source enters through the backwash inlet and the ozone catalyst is washed separately from bottom to top. The gas washed out is discharged through the backwash exhaust port.

[0034] S2. The backwash liquid and compressed air together from bottom to top backwash the ozone catalyst through the backwash inlet, and the backwash liquid is discharged from the backwash outlet.

[0035] S3. Stop the gas supply and use backwash liquid to perform liquid washing on the ozone catalyst from bottom to top. The backwash liquid is discharged from the backwash drain port.

[0036] In a preferred embodiment of the present invention, the technical features of steps S1-S3 of the gas-liquid backwashing are the same as those described above, and will not be repeated here.

[0037] In this invention, preferably, the ozone catalyst is not specifically limited and can be a common ozone catalyst in the art. For example, the ozone catalyst includes at least one of alumina-based catalysts, silica-alumina-based catalysts, ceramsite-based catalysts, and activated carbon-based catalysts according to the carrier classification; and according to the shape classification, the ozone catalyst includes spherical and / or columnar shapes.

[0038] In this invention, preferably, there is no special limitation on the average particle size of the ozone catalyst, and it can be dynamically selected according to the actual production requirements. For example, the average particle size of the spherical ozone catalyst can be 2-8 mm (for example, it can be any two values ​​formed by 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, and 8 mm, or the value within the range), and more preferably it can be 3-5 mm; the particle size of the columnar ozone catalyst can be Φ(2-6)×(5-10) mm, and more preferably it can be Φ(3-4)×(6-8) mm.

[0039] In this invention, preferably, there is no particular limitation on the compressive strength of the ozone catalyst. For example, the compressive strength of the ozone catalyst can be 40-200 N / particle (for example, it can be any two values ​​formed by 40 N / particle, 50 N / particle, 60 N / particle, 70 N / particle, 80 N / particle, 90 N / particle, 100 N / particle, 110 N / particle, 120 N / particle, 130 N / particle, 140 N / particle, 150 N / particle, 160 N / particle, 170 N / particle, 180 N / particle, 190 N / particle, and 200 N / particle, or a value within the range), and more preferably, it can be 50-150 N / particle.

[0040] In a preferred embodiment of the present invention, the method for evaluating the lifetime of the ozone catalyst of the present invention can be used to evaluate ozone catalysts treated under a wide range of wastewater treatment conditions, for example, wastewater with a floating matter content ≤50mg / L, hardness ≤300mg / L, salt content ≤5000mg / L, chemical oxygen demand ≤1000mg / L, and pH 6-9; more preferably, the wastewater has a floating matter content ≤8mg / L, hardness ≤300mg / L, salt content ≤2000mg / L, chemical oxygen demand ≤100mg / L, and pH 6-9.

[0041] It is understood that the service life standards for different ozone catalysts vary. The minimum service life requirement for the ozone catalyst described in this invention should meet the following conditions: when the compressive strength is lower than (10±3) N / particle or the particle size compliance is lower than (30±3)%, either condition is met, indicating that the ozone catalyst has reached its service life. For example: for aluminum-based spherical ozone catalysts, when the compressive strength is lower than (50±3) N / particle or the particle size compliance is lower than (45±3)%, either condition is met, indicating that the ozone catalyst has reached its service life; for carbon-based columnar ozone catalysts, when the compressive strength is lower than (10±3) N / particle or the particle size compliance is lower than (50±3)%, either condition is met, indicating that the ozone catalyst has reached its service life; for ceramic spherical ozone catalysts, when the compressive strength is lower than (75±3) N / particle or the particle size compliance is lower than (40±3)%, either condition is met, indicating that the ozone catalyst has reached its service life.

[0042] It is understood that the ozone catalyst lifetime evaluation method of the present invention is the lifetime of the ozone catalyst under non-extreme environments, and the lifetime of the ozone catalyst operating under optimal conditions is closer to its actual lifetime.

[0043] In this invention, in order to further improve the accuracy of the ozone catalyst lifetime evaluation method, the wastewater used in the ozone catalyst lifetime evaluation method can be kept consistent with the composition of wastewater in the actual use process.

[0044] It is understood that the ozone catalyst life evaluation method of the present invention yields an ozone catalyst lifespan that is basically consistent with the ozone catalyst lifespan obtained after the actual treatment of the aforementioned wastewater. The ozone catalyst lifespan evaluation method of the present invention has high accuracy and a short evaluation cycle.

[0045] The present invention will be described in detail below through examples. In the following examples, the compressive strength and particle size qualification parameters can be determined by referring to the method in industrial activated alumina "HG / T 3927-2020"; the aluminum-based spherical heterogeneous ozone catalyst (average particle size of 4 mm) is a commercially available product of Sinochem Environmental Science and Technology Engineering Co., Ltd., with the brand name ET-CY01, and its service life is 6-8 years in its technical parameters; the carbon-based columnar heterogeneous ozone catalyst (catalyst size of Φ3×6 mm) is a commercially available product of Sinochem Environmental Science and Technology Engineering Co., Ltd., with the brand name ET-CY05, and its service life is 1-2 years in its technical parameters; the ceramsite-based spherical heterogeneous ozone catalyst (catalyst size of Φ5 mm) is a commercially available product of Sinochem Environmental Science and Technology Engineering Co., Ltd., with the brand name ET-CY07, and its service life is 4-6 years in its technical parameters.

[0046] Example 1

[0047] The ozone catalyst evaluated in this embodiment is an aluminum-based spherical heterogeneous ozone catalyst with an average particle size of 4 mm. Each backwash simulates the loss of the ozone catalyst under actual operating conditions for one year. The operation steps of the extreme gas-water backwash are as follows:

[0048] (1) Individual air washing: Close the backwash inlet and outlet, open the backwash air inlet and outlet, and start individual air washing with an air washing intensity of 25 L·m. -2 ·s -1 The air washing time is 10 hours and the air washing temperature is 25℃.

[0049] (2) Combined air-water backwashing: Open the backwash inlet and outlet, adjust the air-washing intensity, and start the combined air-water backwashing. The air-washing intensity is 15 L·m. -2 ·s -1 The water washing strength is 6 L·m -2 ·s -1 The backwashing time is 5 hours and the backwashing temperature is 25℃.

[0050] (3) Separate water wash: Close the backwash air inlet and backwash exhaust outlet, and adjust the backwash water intensity to 10 L·m -2 ·s -1 The backwashing time is 10 hours, and the water washing temperature is 25℃.

[0051] The backwash air source of this invention is a blower. The water quality indicators of the backwash inlet water are: SS = 5 mg / L, hardness = 250 mg / L, salt content = 500 mg / L, COD = 10 mg / L, and pH value = 6.5.

[0052] Five extreme backwashes were performed following the above operating steps. After each backwash, the ozone catalyst was dried at 200°C for 2 hours. After natural cooling, the physical properties of the ozone catalyst were tested. The test indicators included compressive strength and particle size compliance. The test results are shown in Table 1.

[0053] Table 1

[0054]

[0055]

[0056] In the table, "*" indicates the physical properties of the catalyst before backwashing.

[0057] Based on the data in Table 1, through Based on annual calculations, T = 5.8 according to compressive strength and T = 7.2 according to particle size compliance. Taking the minimum value, the estimated service life of the aluminum-based spherical heterogeneous ozone catalyst is 5.8 years.

[0058] Example 2

[0059] The ozone catalyst evaluated in this embodiment is a carbon-based columnar heterogeneous ozone catalyst with a catalyst size of Φ3×6mm. Each backwash simulates the loss of the ozone catalyst under actual operating conditions for one year. The operation steps of the extreme gas-water backwash are as follows:

[0060] (1) Individual air washing: Close the backwash inlet and outlet, open the backwash air inlet and outlet, and start individual air washing with an air washing intensity of 25 L·m. -2 ·s -1 The air washing time is 10 hours and the air washing temperature is 20℃.

[0061] (2) Combined air-water backwashing: Open the backwash inlet and outlet, adjust the air-washing intensity, and start the combined air-water backwashing. The air-washing intensity is 15 L·m. -2 ·s -1 The water washing strength is 6 L·m -2 ·s -1 The backwashing time is 5 hours, and the air washing temperature is 20℃.

[0062] (3) Separate water wash: Close the backwash air inlet and backwash exhaust outlet, and adjust the backwash water intensity to 10 L·m -2 ·s -1 The backwashing time is 10 hours, and the air washing temperature is 20℃.

[0063] The backwash air source of this invention is a blower. The water quality indicators of the backwash inlet water are: SS = 4 mg / L, hardness = 200 mg / L, salt content = 300 mg / L, COD = 8 mg / L, pH value = 7.0.

[0064] Three extreme backwashes were performed following the above operating steps. After each backwash, the ozone catalyst was dried at 200°C for 2 hours. After natural cooling, the physical properties of the ozone catalyst were tested. The test indicators included compressive strength and particle size compliance. The test results are shown in Table 2.

[0065] Table 2

[0066] Experimental batch Compressive strength (N / particle) Particle size compliance (%) <![CDATA[0 * ]]> 80 100 1 43 82 2 10 64 3 8 42

[0067] In the table, "*" indicates the physical properties of the catalyst before backwashing.

[0068] Based on the data in Table 2, through Based on annual calculations, T = 1.9 according to compressive strength and T = 2.9 according to particle size compliance. Taking the minimum value, the estimated service life of the carbon-based spherical heterogeneous ozone catalyst is 1.9 years.

[0069] Example 3

[0070] The ozone catalyst evaluated in this embodiment is a ceramic-based spherical heterogeneous ozone catalyst with a catalyst size of Φ5mm. Each backwash simulates the loss of the ozone catalyst under actual operating conditions for one year. The operation steps of the extreme gas-water backwash are as follows:

[0071] (1) Individual air washing: Close the backwash inlet and outlet, open the backwash air inlet and outlet, and start individual air washing with an air washing intensity of 25 L·m. -2 ·s -1 The air washing time is 10 hours and the air washing temperature is 30℃.

[0072] (2) Combined air-water backwashing: Open the backwash inlet and outlet, adjust the air-washing intensity, and start the combined air-water backwashing. The air-washing intensity is 15 L·m. -2 ·s -1 The water washing strength is 6 L·m -2 ·s -1 The backwashing time is 5 hours and the backwashing temperature is 30℃.

[0073] (3) Separate water wash: Close the backwash air inlet and backwash exhaust outlet, and adjust the backwash water intensity to 10 L·m -2 ·s -1 The backwashing time is 10 hours, and the water washing temperature is 30℃.

[0074] The backwash air source of this invention is a blower. The water quality indicators of the backwash inlet water are: SS = 5 mg / L, hardness = 100 mg / L, salt content = 200 mg / L, COD = 10 mg / L, pH value = 7.5.

[0075] Perform 10 extreme backwashes according to the above operating steps. After each backwash, dry the ozone catalyst at 200°C for 2 hours. After natural cooling, test the physical properties of the ozone catalyst, including compressive strength and particle size compliance.

[0076] Table 3

[0077] Experimental batch Compressive strength (N / particle) Particle size compliance (%) <![CDATA[0 * ]]> 150 100 1 136 88 2 115 76 3 103 66 4 95 50 5 88 42 6 78 36 7 64 30 8 50 21 9 43 18 10 35 15

[0078] In the table, "*" indicates the physical properties of the catalyst before backwashing.

[0079] Based on the data in Table 3, through Based on annual calculations, T = 7.5 according to compressive strength and T = 5.8 according to particle size compliance. Taking the minimum value, the estimated service life of the carbon-based spherical heterogeneous ozone catalyst is 5.8 years.

[0080] Example 4

[0081] The lifetime of the ozone catalyst was evaluated according to the method of Example 1, except that the gas scrubbing intensity was 12 L·m during the individual gas scrubbing in step (1). -2 ·s -1 The air washing time was 12 hours, and the air washing temperature was 35℃. The test results are shown in Table 4.

[0082] Table 4

[0083] Experimental batch Compressive strength (N / particle) Particle size compliance (%) <![CDATA[0 * ]]> 140 100 1 125 92 2 116 80 3 110 71 4 103 66 5 94 58

[0084] In the table, "*" indicates the physical properties of the catalyst before backwashing.

[0085] Based on the data in Table 4, through Based on annual calculations, T = 11.1 according to compressive strength and T = 8.4 according to particle size compliance. Taking the minimum value, the estimated service life of the aluminum-based spherical heterogeneous ozone catalyst is 8.4 years.

[0086] Example 5

[0087] The lifetime of the ozone catalyst was evaluated according to the method in Example 1, except that the gas washing intensity was 20 L / m³ during the combined gas-water backwashing in step (2). 2 •s, washing strength is 8L / m 2 The test results are shown in Table 5.

[0088] Table 5

[0089]

[0090]

[0091] In the table, "*" indicates the physical properties of the catalyst before backwashing.

[0092] Based on the data in Table 5, through Based on annual calculations, T = 6.1 according to compressive strength and T = 7.0 according to particle size compliance. Taking the minimum value, the estimated service life of the aluminum-based spherical heterogeneous ozone catalyst is 6.1 years.

[0093] Example 6

[0094] The lifetime of the ozone catalyst was evaluated according to the method of Example 1, except that the water washing intensity was 12 L / m during the separate water washing in step (3). 2 The test results are shown in Table 6.

[0095] Table 6

[0096] Experimental batch Compressive strength (N / particle) Particle size compliance (%) <![CDATA[0 * ]]> 140 100 1 120 93 2 104 86 3 88 70 4 69 66 5 60 50

[0097] In the table, "*" indicates the physical properties of the catalyst before backwashing.

[0098] Based on the data in Table 6, through Based on annual calculations, T = 6.4 according to compressive strength and T = 7.9 according to particle size compliance. Taking the minimum value, the estimated service life of the aluminum-based spherical heterogeneous ozone catalyst is 6.4 years.

[0099] Comparative Example 1

[0100] The lifetime of the ozone catalyst was evaluated according to the method in Example 1, except that the combined gas-water backwashing and water washing in steps (2) and (3) were not performed; only a gas washing was performed, with the gas washing time being 25 hours. The test results are shown in Table 7.

[0101] Table 7

[0102] Experimental batch Compressive strength (N / particle) Particle size compliance (%) <![CDATA[0 * ]]> 140 100 1 126 90 2 120 83 3 112 76 4 106 70 5 95 66

[0103] In the table, "*" indicates the physical properties of the catalyst before backwashing.

[0104] Based on the data in Table 7, through Based on annual calculations, T = 13.5 according to compressive strength and T = 12.6 according to particle size compliance. Taking the minimum value, the estimated service life of the aluminum-based spherical heterogeneous ozone catalyst is 12.6 years.

[0105] Comparative Example 2

[0106] The lifetime of the ozone catalyst was evaluated according to the method in Example 1, except that step (2) of combined gas and water backwashing was not performed; only gas washing and water washing were performed separately. The time for gas washing alone was 12.5 hours, and the time for water washing alone was 12.5 hours. The test results are shown in Table 8.

[0107] Table 8

[0108]

[0109] In the table, "*" indicates the physical properties of the catalyst before backwashing.

[0110] Based on the data in Table 8, through Based on annual calculations, T = 9.1 according to compressive strength and T = 9.8 according to particle size compliance. Taking the minimum value, the estimated service life of the aluminum-based spherical heterogeneous ozone catalyst is 9.1 years.

[0111] Comparative Example 3

[0112] The lifetime of the ozone catalyst was evaluated according to the method in Example 1, except that the separate gas washing and combined gas-water backwashing in steps (1) and (2) were not performed; only a separate water washing was performed, with the water washing time being 25 hours. The test results are shown in Table 9.

[0113] Table 9

[0114] Experimental batch Compressive strength (N / particle) Particle size compliance (%) <![CDATA[0 * ]]> 140 100 1 120 91 2 105 79 3 97 70 4 86 63 5 80 58

[0115] In the table, "*" indicates the physical properties of the catalyst before backwashing.

[0116] Based on the data in Table 9, through Based on annual calculations, T = 9.5 according to compressive strength and T = 9.7 according to particle size compliance. Taking the minimum value, the estimated service life of the aluminum-based spherical heterogeneous ozone catalyst is 9.5 years.

[0117] Comparative Example 4

[0118] The lifetime of the ozone catalyst was evaluated according to the method in Example 1, except that the separate gas washing and separate water washing in steps (1) and (3) were not performed; only a combined gas-water backwash was performed, with the combined gas-water backwash lasting for 25 hours. The test results are shown in Table 10.

[0119] Table 10

[0120] Experimental batch Compressive strength (N / particle) Particle size compliance (%) <![CDATA[0 * ]]> 140 100 1 123 92 2 110 85 3 93 78 4 92 66 5 85 59

[0121] In the table, "*" indicates the physical properties of the catalyst before backwashing.

[0122] Based on the data in Table 10, through Based on annual calculations, T = 10.7 according to compressive strength and T = 10.0 according to particle size compliance. Taking the minimum value, the estimated service life of the aluminum-based spherical heterogeneous ozone catalyst is 10 years.

[0123] In this invention, the ozone catalyst lifetime evaluation method of this invention is more accurate when the wastewater used in the lifetime evaluation method is consistent with the wastewater used in the actual treatment process.

[0124] The wastewater introduced into the control group above is only to illustrate the accuracy of the evaluation method of the present invention, and is not intended to be limited to wastewater with the above composition. Because the actual wastewater treatment cycle is too long, only one type of influent water was used in the experiment to ensure parallel processing. Furthermore, the above embodiments also demonstrate that even with different treatment conditions, the lifespan of the ozone catalyst can be accurately determined.

[0125] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for evaluating the lifetime of an ozone catalyst, characterized in that, The method includes: performing at least one gas-liquid backwash on the ozone catalyst; The steps of each gas-liquid backwashing include: sequentially performing gas washing, combined gas-liquid washing, and liquid washing on the ozone catalyst; The number of gas-liquid backwashes is i, and the service life of the ozone catalyst is negatively correlated with the compressive strength or particle size qualification after the i-th gas-liquid backwash.

2. The method according to claim 1, wherein, The calculation method for the service life of the ozone catalyst is as follows: Year, T represents the lifespan of the ozone catalyst, X i The compressive strength or particle size qualification degree after the i-th gas-liquid backwash, where i is an integer from 1 to n; X i The T value and X calculated when the compressive strength is... i The T-values ​​calculated for particle size compliance are compared, and the smaller one is taken as the service life of the ozone catalyst. And / or, the gas source for the gas scrubbing comes from at least one of a blower, compressed air, and pressure swing adsorption; And / or, the conditions relative to the gas scrubbing include: a gas scrubbing intensity of 12-28 L·m -2 ·s -1 Preferably 15-25 L·m -2 ·s -1 The air washing time is 4-12 hours, preferably 5-10 hours; the air washing temperature is 15-35℃, preferably 20-30℃.

3. The method according to claim 1, wherein, The liquid used for the combined gas-liquid washing and liquid washing is selected from at least one of tap water, salt water, and circulating cooling water.

4. The method according to claim 1 or 3, wherein, The inlet requirements for the gas-liquid combined washing and liquid washing include: suspended solids content ≤10mg / L, hardness ≤300mg / L, salt content ≤1000mg / L, COD ≤20mg / L, and pH value 6-9. Preferably, the influent requirements for the gas-liquid combined washing and liquid washing include: suspended solids content ≤ 5 mg / L, hardness ≤ 250 mg / L, salt content ≤ 500 mg / L, COD ≤ 10 mg / L, and pH value 6.5-8.

5. The method according to any one of claims 1-3, wherein, The conditions for the combined gas-liquid scrubbing include: a gas scrubbing intensity of 10-20 L·m. -2 ·s -1 Preferably 12-15 L·m -2 ·s -1 The washing strength is 2-8 L·m. -2 ·s -1 Preferably 4-6 L·m -2 ·s -1 The combined gas-liquid backwashing time is 2-6 hours, preferably 3-5 hours; the combined gas-liquid backwashing temperature is 15-35℃, preferably 20-30℃.

6. The method according to any one of claims 1-3, wherein, The conditions for liquid washing include: a washing intensity of 4-12 L·m. -2 ·s -1 Preferably 5-10 L·m -2 ·s -1 The washing time is 5-12 hours, preferably 6-10 hours; the washing temperature is 15-35℃, preferably 20-30℃.

7. The method according to claim 1, wherein, The method further includes: drying the catalyst after gas-liquid backwashing and then performing performance testing; wherein the drying temperature is 200-400℃ and the drying time is 2-5h.

8. The method according to any one of claims 1-3, wherein, The gas-liquid backwashing step includes: S1. The gas source enters through the backwash inlet and the ozone catalyst is washed separately from bottom to top. The gas washed out is discharged through the backwash exhaust port. S2. The backwash liquid and compressed air together from bottom to top backwash the ozone catalyst through the backwash inlet, and the backwash liquid is discharged from the backwash outlet. S3. Stop the gas supply and use backwash liquid to perform liquid washing on the ozone catalyst from bottom to top. The backwash liquid is discharged from the backwash drain port.

9. The method according to claim 1, wherein the ozone catalyst, classified according to the carrier, comprises: At least one of alumina-based catalysts, silica-alumina-based catalysts, ceramsite-based catalysts, and activated carbon-based catalysts; And / or, classified by shape, the ozone catalyst includes: spherical and / or columnar shapes.

10. The method according to claim 9, wherein, The average particle size of the spherical ozone catalyst is 2-8 mm, preferably 3-5 mm; And / or, the particle size of the columnar ozone catalyst is Φ(2-6)×(5-10)mm, preferably Φ(3-4)×(6-8)mm; And / or, the compressive strength of the ozone catalyst is 40-200 N / particle, preferably 50-150 N / particle.

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