A method for testing the dust removal effect of nanofluid

Abstract

The application provides a nanofluid dust removal effect test method. The method designs a new dust removal system as much as possible beneficial to dust adsorption through analysis of physical properties and adsorption of the nanofluid, the system sets corresponding adjusting devices for main influencing factors of the nanofluid dust removal effect, and realizes full process recording of the nanofluid dust removal under different influencing factors. The test method with adjustable variables is formed according to the device, the method puts forward two new evaluation indexes, and realizes quantitative analysis of the nanofluid dust removal effect through absorption rate and utilization rate. The nanofluid dust removal effect can be further predicted, and the selection of the nanofluid under different conditions is provided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of dust control, in particular to a nanofluid dust removal effect testing method. BACKGROUND

[0002] Dust is a common floating particulate matter in construction sites, mining sites, industrial yards, processing workshops and other places, which is generated by external forces such as human power, wind power and mechanical force. High concentration of dust can increase the wear rate of production machinery and equipment, and can cause respiratory system and cardiovascular diseases in workers, and can even cause dust explosion under certain conditions. Therefore, most production industries such as mining, metal smelting and construction have put forward important requirements for dust removal technology.

[0003] Wet dust removal technology is a technology in which dust removal liquid acts on dust-containing gas to prevent dust from escaping and purify the gas environment. Wet dust removal technology has the characteristics of high efficiency, simple structure of dust removal device, low cost, small land occupation, convenient operation and maintenance, and is particularly suitable for treating high-temperature, high-humidity, flammable and explosive dust-containing gas, so it has been widely used.

[0004] As the key of wet dust removal, the selection of dust removal liquid has an important influence on the dust removal effect. Compared with the widely used water, the selection of liquid with stronger adsorption capacity for dust can significantly improve the effect of wet dust removal.

[0005] Nanofluid is a new type of fluid material, which has excellent adsorption capacity due to its nanoscale size. However, there is no related testing device and testing method for testing the dust removal effect of nanofluid at present, which limits the application of nanofluid as dust removal liquid. It is also impossible to provide objective and accurate basis for selecting appropriate nanofluid types, particle sizes, concentrations and other influencing factors.

[0006] Therefore, it is of great significance to provide a nanofluid dust removal effect testing method for the application of nanofluid in the field of dust removal. SUMMARY

[0007] The purpose of the present application is to provide a nanofluid dust removal effect testing method to solve the problems in the prior art.

[0008] The technical solution adopted to achieve the purpose of the present application is as follows: a nanofluid dust removal effect testing method, which uses a nanofluid dust removal system to test the dust removal effect of nanofluid.

[0009] The nanofluid dust removal system includes a nanofluid testing system, a nanofluid recovery system and a nanofluid preparation system.

[0010] The nanofluid test system comprises a dust removal chamber, a spray pipe network and a dust concentration meter. The dust removal chamber comprises a dust removal cavity and a dust hopper in communication. The dust hopper is arranged below the dust removal cavity. The dust hopper is communicated with the nanofluid recovery system through a nanofluid output pipe. An air inlet, an air outlet and a liquid inlet are arranged on the outer wall of the dust removal cavity. The air inlet, the air outlet and the liquid inlet communicate the inner cavity of the dust removal cavity with the external environment. The dust concentration meters are arranged at the positions of the air inlet and the air outlet, respectively, to measure the dust concentration in the gas before and after dust removal.

[0011] The spray pipe network comprises a nanofluid input pipe and a spray head. The nanofluid input pipe is communicated with the nanofluid preparation system. The nanofluid input pipe extends into the inner cavity of the dust removal cavity through the liquid inlet. A plurality of spray heads are connected to the nanofluid input pipe.

[0012] The nanofluid dust removal effect test method specifically comprises the following steps:

[0013] 1) Prepare a nanofluid.

[0014] 2) The nanofluid forms a spray in the dust removal cavity through the spray head, and the dust enters through the air inlet and is adsorbed by the nanofluid spray and then settles. The remaining gas is discharged through the air outlet. The nanofluid droplets adsorbed with the dust are collected by the dust hopper and injected into the nanofluid recovery system through the nanofluid output pipe.

[0015] 3) The nanofluid adsorbed with the dust gradually settles and stratifies in the nanofluid recovery system. The upper layer of the nanofluid is taken to study and analyze the changes in the properties of the nanofluid after dust removal.

[0016] 4) Calculate the nanofluid absorption rate and the nanofluid utilization rate.

[0017] 5) Change the working conditions and number, and repeat the steps 1) to 4). Explore the change rules of the nanofluid absorption rate, the nanofluid utilization rate and the properties of the nanofluid after dust removal under different working conditions.

[0018] Further, the calculation formula of the nanofluid absorption rate is shown as formula (1).

[0019]

[0020] In the formula, C1 is the dust concentration of the air inlet, mg / m3. C2 is the dust concentration of the air outlet, mg / m3.

[0021] Further, the nanofluid recovery system comprises a separation cavity. The dust hopper is communicated with the inner cavity of the separation cavity through a nanofluid output pipe. A liquid outlet is arranged on the side wall of the separation cavity. The liquid outlet communicates the inner cavity of the separation cavity with the external environment. A valve group is arranged on the pipeline of the liquid outlet. A Zeta potential instrument, a surface tension instrument and an absorbance detector are arranged in the separation cavity.

[0022] Further, the nanofluid preparation system comprises a preparation cavity and a liquid pump. The preparation cavity is in the form of a box structure. A nanoparticle adding port and a water adding port are arranged on the top wall of the preparation cavity. An ultrasonic vibrator is attached to the inner wall of the preparation cavity. The preparation cavity contains a nanofluid primary liquid. A Zeta potential instrument, a surface tension instrument and an absorbance detection instrument are arranged in the inner cavity of the preparation cavity. The nanofluid input pipe is provided with a liquid pump.

[0023] Further, the calculation formula of the nanofluid utilization rate based on the potential change is shown as formula (2). The calculation formula of the nanofluid utilization rate based on the tension change is shown as formula (3). The calculation formula of the nanofluid utilization rate based on the absorbance change is shown as formula (4).

[0024]

[0025]

[0026]

[0027] In the formula, U1 is the potential of the nanofluid at the separation cavity, mV. U2 is the potential of the nanofluid at the preparation cavity, mV. In the formula, σ1 is the surface tension of the nanofluid at the separation cavity, mN / m. σ2 is the surface tension of the nanofluid at the preparation cavity, mN / m. A1 is the absorbance of the nanofluid at the separation cavity, L / (mol·cm). A2 is the absorbance of the nanofluid at the preparation cavity, L / (mol·cm).

[0028] Further, the dust removal cavity is further provided with a support. The spray head is mounted on the support.

[0029] Further, in step 5), the working conditions are changed, such as the type of nanofluid, the particle size of nanofluid, the concentration of nanofluid, the pressure of spray head, the number of spray heads and the environment temperature of the dust removal cavity.

[0030] Further, the dust removal cavity is provided with a temperature changer in the inner cavity.

[0031] Further, the dust removal cavity is in the form of a box structure.

[0032] Further, the ash bucket is in the form of a cone or a funnel structure.

[0033] The technical effects of the present application are self-evident:

[0034] A. The present application further proposes the utilization rate of nanofluid on the basis of the nanofluid dust removal efficiency, realizes the quantitative analysis of the property change of nanofluid before and after dust removal, and provides a basis for the evaluation of nanofluid dust removal capacity.

[0035] B.The application realizes the influence analysis of influencing factors such as the type, particle size, concentration of nanofluid, nozzle pressure, quantity, and environmental temperature on the absorption rate and utilization rate of nanofluid, and provides a theoretical basis for improving the dust removal effect of nanofluid;

[0036] C.The application provides a nanofluid dust removal effect test method, which provides an experimental basis for subsequent research on the dust removal properties of nanofluid and provides a train of thought for promoting the application of nanofluid in dust removal. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 It is a schematic diagram of a nanofluid dust removal system.

[0038] In the figure: air inlet 1, air outlet 2, liquid inlet 3, dust concentration meter 4, support 5, nozzle 6, dust removal cavity 7, ash bucket 8, valve group 9, liquid outlet 10, separation cavity 11, Zeta potential instrument 12, surface tension instrument 13, absorbance detector 14, nanoparticle adding port 15, water inlet 16, ultrasonic vibrator 17, preparation cavity 18, liquid pump 22, nanofluid input pipe 23, nanofluid output pipe 24. DETAILED DESCRIPTION

[0039] The application will be further described below in conjunction with examples, but should not be understood as limiting the above-mentioned subject matter of the application to the following examples. According to ordinary technical knowledge and conventional means in the art, various substitutions and modifications can be made without departing from the technical idea of the application, and all should be included in the protection scope of the application.

[0040] Example 1

[0041] The embodiment provides a nanofluid dust removal effect test method, which adopts a nanofluid dust removal system to test the dust removal effect of nanofluid.

[0042] Referring to Figure 1 , the nanofluid dust removal system includes a nanofluid test system, a nanofluid recovery system, and a nanofluid preparation system.

[0043] The nanofluid test system includes a dust removal chamber, a spray pipe network, and a dust concentration meter 4. The dust removal chamber includes a dust removal cavity 7 and an ash bucket 8 in communication. The ash bucket 8 is arranged below the dust removal cavity 7. The ash bucket 8 is communicated with the nanofluid recovery system through the nanofluid output pipe 24. The dust removal cavity 7 is provided with an air inlet 1, an air outlet 2, and a liquid inlet 3 on the outer wall. The air inlet 1, the air outlet 2, and the liquid inlet 3 communicate the inner cavity of the dust removal cavity 7 with the external environment. The dust concentration meters 4 are arranged at the positions of the air inlet 1 and the air outlet 2, respectively, to measure the dust concentration in the gas before and after dust removal.

[0044] The spray pipe network comprises a nanofluid input pipe 23 and a spray head 6. The nanofluid input pipe 23 is in communication with a nanofluid preparation system. The nanofluid input pipe 23 extends into the inner cavity of the dust removal cavity 7 through the liquid inlet 3. A plurality of spray heads 6 are connected to the nanofluid input pipe 23.

[0045] The nanofluid dust removal effect testing method specifically comprises the following steps:

[0046] 1) Prepare a nanofluid.

[0047] 2) The nanofluid forms a spray in the dust removal cavity 7 through the spray head 6, and the dust enters through the air inlet 1 and is adsorbed by the nanofluid spray and then settles. The remaining gas is discharged through the air outlet 2. The nanofluid droplets adsorbed with the dust are collected by the ash bucket 8 and injected into the nanofluid recovery system through the nanofluid output pipe 24.

[0048] 3) The nanofluid adsorbed with the dust gradually settles and stratifies in the nanofluid recovery system. The upper layer of the nanofluid is taken to study and analyze the changes in the properties of the nanofluid after dust removal.

[0049] 4) Calculate the nanofluid absorption rate and nanofluid utilization rate.

[0050] 5) Change the working conditions and number, and repeat the steps 1) to 4). Explore the change rules of the nanofluid absorption rate, nanofluid utilization rate and properties of the nanofluid after dust removal under different working conditions.

[0051] The embodiment designs a new dust removal system that is as favorable as possible for dust adsorption through the analysis of the physical properties and adsorption of the nanofluid. The system sets corresponding adjusting devices for the main influencing factors of the nanofluid dust removal effect, realizes the whole process recording of the nanofluid dust removal under different influencing factors. The testing method with adjustable variables is formed according to the device, and the quantitative analysis of the nanofluid dust removal effect is realized through the absorption rate and utilization rate. The nanofluid dust removal effect can be further predicted, and the basis for the selection of nanofluids under different conditions is provided.

[0052] Example 2:

[0053] The main content of the embodiment is the same as that of example 1, wherein the calculation formula of the nanofluid absorption rate is shown as formula (1).

[0054]

[0055] In the formula, C1 is the dust concentration at the air inlet, mg / m 3 . C2 is the dust concentration at the air outlet, mg / m 3 .

[0056] Example 3:

[0057] The embodiment mainly includes the same content as the embodiment 1, wherein the nanofluid recovery system comprises a separation chamber 11. The ash chute 8 is communicated with the inner cavity of the separation chamber 11 through a nanofluid output pipe 24. A liquid discharge port 10 is arranged on the side wall of the separation chamber 11. The liquid discharge port 10 communicates the inner cavity of the separation chamber 11 with the external environment. A valve group 9 is arranged on the pipeline of the liquid discharge port 10. A Zeta potential instrument 12, a surface tension instrument 13 and an absorbance detector 14 are arranged in the separation chamber 11. In the embodiment, the Zeta potential instrument 12, the surface tension instrument 13 and the absorbance detector 14 are all installed on the top wall of the separation chamber.

[0058] The nanofluid preparation system comprises a preparation chamber 18 and a liquid pump 22. The preparation chamber 18 is in the form of a box structure as a whole. A nanoparticle adding port 15 and a water injection port 16 are arranged on the top wall of the preparation chamber 18. An ultrasonic vibrator 17 is attached to the inner wall of the preparation chamber 18. The preparation chamber 18 contains a nanofluid primary liquid. A Zeta potential instrument 12, a surface tension instrument 13 and an absorbance detector 14 are arranged in the inner cavity of the preparation chamber 18. In the embodiment, the Zeta potential instrument 12, the surface tension instrument 13 and the absorbance detector 14 are all installed on the top wall of the preparation chamber. The liquid pump 22 is arranged on the pipeline of the nanofluid input pipe 23 communicated with the preparation chamber 18.

[0059] Embodiment 4:

[0060] The embodiment mainly includes the same content as the embodiment 3, wherein the calculation formula of the nanofluid utilization rate based on the potential change is shown as formula (2). The calculation formula of the nanofluid utilization rate based on the tension change is shown as formula (3). The calculation formula of the nanofluid utilization rate based on the absorbance change is shown as formula (4).

[0061]

[0062]

[0063]

[0064] In the formula, U1 is the nanofluid potential at the separation chamber, mV. U2 is the nanofluid potential at the preparation chamber, mV. In the formula, σ1 is the nanofluid surface tension at the separation chamber, mN / m. σ2 is the nanofluid surface tension at the preparation chamber, mN / m. A1 is the nanofluid absorbance at the separation chamber, L / (mol·cm). A2 is the nanofluid absorbance at the preparation chamber, L / (mol·cm).

[0065] It is worth mentioning that the higher the concentration of nanofluid, the greater the absorbance; the absorbance also reflects the stability of the nanofluid. The greater the p, the higher the utilization rate. The higher the concentration of nanofluid, the greater the surface tension. The surface tension also reflects the flowability of the nanofluid. The greater the ω, the higher the utilization rate. The lower the concentration of nanofluid, the better the stability, and the higher the Zeta potential. The greater the p, the higher the utilization rate.

[0066] Embodiment 5:

[0067] The main content of this embodiment is the same as that of any one of embodiments 1-4, wherein the dust removal cavity 7 is further provided with a support 5. The spray head 6 is installed on the support 5.

[0068] Embodiment 6:

[0069] The main content of this embodiment is the same as that of any one of embodiments 1-5, wherein in step 5), the working conditions are changed to the type of nanofluid, the particle size of nanofluid, the concentration of nanofluid, the pressure of spray head, the number of spray heads, and the environmental temperature of the dust removal cavity. The change rules of the absorption rate and utilization rate of different types of nanofluids such as SiO2, TiO2, and Al2O3 are analyzed, and the influence rules of the type of nanofluid on the dust removal capacity and use efficiency of nanofluid are illustrated. Different particle sizes of nanofluids such as 20 nm, 40 nm, 60 nm, and 80 nm are added, the change rules of the absorption rate and utilization rate of different particle sizes of nanofluids are analyzed, and the influence rules of the particle size of nanofluid on the dust removal capacity and use efficiency of nanofluid are illustrated. Different masses of nanofluids such as 50 g, 100 g, 150 g, and 200 g are added, the change rules of the absorption rate and utilization rate of different concentrations of nanofluids are analyzed, and the influence rules of the concentration of nanofluid on the dust removal capacity and use efficiency of nanofluid are illustrated. The pressure of the spray head is changed, the change rules of the absorption rate and utilization rate of nanofluid under different spray head pressures are analyzed, and the influence rules of the spray head pressure on the dust removal capacity and use efficiency of nanofluid are illustrated. The number of spray heads is changed, the change rules of the absorption rate and utilization rate of nanofluid under different numbers of spray heads are analyzed, and the influence rules of the number of spray heads on the dust removal capacity and use efficiency of nanofluid are illustrated. The temperature of the dust removal cavity 7 is changed, the change rules of the absorption rate and utilization rate of nanofluid under different temperatures are analyzed, and the influence rules of the environmental temperature on the dust removal capacity and use efficiency of nanofluid are illustrated.

[0070] Embodiment 7:

[0071] The main content of this embodiment is the same as that of any one of embodiments 1-6, wherein a temperature changer 25 is arranged in the inner cavity of the dust removal cavity 7. The temperature of the dust removal cavity 7 is changed by the temperature changer 25.

[0072] Embodiment 8:

[0073] The embodiment mainly comprises the same content as any one of embodiments 1-7, wherein the dust removal cavity 7 is a box structure.

[0074] Embodiment 9:

[0075] The embodiment mainly comprises the same content as any one of embodiments 1-8, wherein the ash bucket 8 is a conical or funnel-shaped structure.

[0076] Embodiment 10:

[0077] The embodiment mainly comprises the same content as any one of embodiments 1-9, wherein after step 5) is completed, the influencing factors such as the type, particle size, and concentration of the nanofluid obtained through multiple experiments, the pressure and number of the spray head, and the environmental temperature form a nanofluid dust removal effect database corresponding to the absorption rate and utilization rate. A prediction model of the nanofluid dust removal effect is constructed through a BP neural network, the main influencing factors are used as 6 neurons of the input layer, the absorption rate and utilization rate are used as 2 neurons of the output layer, 3 hidden layer neurons are set, the hidden layer excitation function is tansig, the output layer excitation function is logsig, the training function is traingdx, the performance function is mse, and the iteration number epochs is 5000 times. The data obtained through the experiments are divided into 3 independent data sets, i.e., a training set, a test set, and a validation set, which respectively account for 70%, 15%, and 15% of the database. The network is trained using the training set, and the test set is used to test the current network whenever the iteration number is reached. The network with the minimum error is selected as the final network, which is verified through the validation set. The nanofluid dust removal effect under multiple factor comprehensive conditions is predicted based on the model, and the best condition for using the nanofluid for dust removal is determined.

Claims

1. A method for testing the dust removal effect of a nanofluid, characterized in that: The nanofluid dust removal system is used to test the nanofluid dust removal effect; The nanofluid dust removal system comprises a nanofluid test system, a nanofluid recovery system and a nanofluid preparation system; The nanofluid test system comprises a dust removal chamber, a spraying pipe network and a dust concentration meter (4); the dust removal chamber comprises a dust removal cavity (7) and a dust hopper (8) in communication; the dust hopper (8) is arranged below the dust removal cavity (7); the dust hopper (8) is communicated with the nanofluid recovery system through a nanofluid output pipe (24); an air inlet (1), an air outlet (2) and a liquid inlet (3) are arranged on the outer wall of the dust removal cavity (7); the air inlet (1), the air outlet (2) and the liquid inlet (3) are communicated with the inner cavity of the dust removal cavity (7) and the external environment; the dust concentration meters (4) are arranged at the positions of the air inlet (1) and the air outlet (2), respectively, to measure the dust concentration in the gas before and after dust removal; The spraying pipe network comprises a nanofluid input pipe (23) and a spray head (6); the nanofluid input pipe (23) is communicated with the nanofluid preparation system; the nanofluid input pipe (23) extends into the inner cavity of the dust removal cavity (7) through the liquid inlet (3); a plurality of spray heads (6) are connected to the nanofluid input pipe (23); The nanofluid dust removal effect test method specifically comprises the following steps: 1) preparing nanofluid; 2) the nanofluid forms a spray in the dust removal cavity (7) through the spray head (6), the dust enters through the air inlet (1) and is adsorbed by the nanofluid spray and then settles down, the remaining gas is discharged through the air outlet (2), the nanofluid droplets adsorbing the dust are collected by the dust hopper (8) and are injected into the nanofluid recovery system through the nanofluid output pipe (24); 3) the nanofluid adsorbing the dust gradually settles down and is layered in the nanofluid recovery system; the nanofluid in the upper layer is taken to study and analyze the property change of the nanofluid after dust removal; 4) calculating the nanofluid absorption rate and the nanofluid utilization rate; the calculation formula of the nanofluid utilization rate based on the potential change is shown as formula (1); the calculation formula of the nanofluid utilization rate based on the tension change is shown as formula (2); the calculation formula of the nanofluid utilization rate based on the absorbance change is shown as formula (3); (1) (2) (3) wherein is the nanofluidic potential at the separation chamber, mV; is the nanofluidic potential at the preparation chamber, mV; wherein is the nanofluidic surface tension at the separation chamber, mN / m; is the nanofluidic surface tension at the preparation chamber, mN / m; is the nanofluidic absorbance at the separation chamber, L / (mol-cm); is the nanofluidic absorbance at the preparation chamber, L / (mol-cm); 5) changing the working conditions and numbering, repeating the steps 1) to 4); exploring the change rules of the nanofluid absorption rate, the nanofluid utilization rate and the property of the nanofluid after dust removal under different working conditions.

2. The method according to claim 1, wherein: The calculation formula of the nanofluid absorption rate is shown as formula (4); (4) wherein is the inlet dust concentration, mg / m 3 ; is the outlet dust concentration, mg / m 3 . 3.The method according to claim 1, characterized in that: The nanofluid recovery system comprises a separation cavity (11); the dust hopper (8) is communicated with the inner cavity of the separation cavity (11) through the nanofluid output pipe (24); a liquid discharge port (10) is arranged on the side wall of the separation cavity (11); the liquid discharge port (10) is communicated with the inner cavity of the separation cavity (11) and the external environment; a valve group (9) is arranged on the pipeline of the liquid discharge port (10); a Zeta potential instrument (12), a surface tension instrument (13) and an absorbance detector (14) are arranged in the separation cavity (11).

4. The method according to claim 3, wherein: The nanofluid preparation system comprises a preparation cavity (18) and a liquid pump (22); the preparation cavity (18) is in the form of a box structure as a whole; a nanoparticle adding port (15) and a water injection port (16) are arranged on the top wall of the preparation cavity (18); an ultrasonic vibrator (17) is attached to the inner wall of the preparation cavity (18); the preparation cavity (18) contains a nanofluid initial liquid; a Zeta potential instrument (12), a surface tension instrument (13) and an absorbance detector (14) are arranged in the inner cavity of the preparation cavity (18); and the nanofluid input pipe (23) is provided with the liquid pump (22) on the pipeline in communication with the preparation cavity (18).

5. The method according to claim 1, wherein: The dust removal cavity (7) is further provided with a support (5); and the spray head (6) is mounted on the support (5). 6.The method according to claim 1, wherein: In step 5), the working conditions are changed, such as the type of nanofluid, the particle size of nanofluid, the concentration of nanofluid, the pressure of spray head, the number of spray heads and the environmental temperature of dust removal cavity.

7. The method according to claim 1, wherein the method is characterized by: The dust removal cavity (7) is provided with a temperature changer (25) in the inner cavity. 8.The method according to claim 1, wherein: The dust removal cavity (7) is in the form of a box structure. 9.The method according to claim 1, wherein: The ash bucket (8) is in the form of a cone or a funnel structure.

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