TWI697470B - Rapid methylene blue test method - Google Patents

Abstract

A rapid methylene blue test method is disclosed. Methylene blue solution is used to titrate the sample of fine aggregates from a specific source, so as to obtain a calibration curve equation and acceptance ranges for that fine aggregates, which is used as the basis for the subsequent acceptance of the fine aggregates from the same source. Compared with the prior art, in addition to saving operation time and reducing the amount of work of the personnel, the present invention is also possible to roughly analyze the components in the fine aggregates as a basis for adding surfactants.

Description

Fast screening method of methylene blue for sand and gravel

The invention relates to a fast screening method for fine sand and gravel materials, in particular to a fast screening method for detecting methylene blue of fine sand and gravel materials.

For any product manufacturer, before manufacturing the product, it is necessary to confirm whether the incoming material meets the specification requirements. The same is true for concrete manufacturers. Generally speaking, concrete mainly includes coarse aggregates, fine aggregates, cement and chemical additives (interface active agents), etc. The fine aggregates include fine sand and mud that people often say, and the boundary is the No. 200 screen (grain Diameter 75µm). Although the source of fine-grained materials is fixed (such as a stream sand, construction excavation sand, and machine-made sand), each batch of incoming materials may come from a different location of the source of the material, and is affected by changes in natural landforms and environmental climate. The ratio of fine sand to mud may be different. Because the mud will adsorb the surfactant, the characteristics of the concrete will change. Therefore, how to determine the sludge content in a batch of fine particles to meet the feed demand is a very important topic.

Generally speaking, the ready-mixed concrete plant will use the CNS491 specification to find out the mud content in a batch of fine-grained materials. However, it takes a long time (several days) to operate in accordance with the CNS491 specification, which only increases the time cost of the concrete ready-mix plant. In addition, although the CNS491 standard can find out the mud content, it cannot define the adsorption capacity of the mud components to the surfactant. Two batches of fine particles of the same source with the same mud content may be due to differences in chemical substances in the mud composition, resulting in a batch of interface active agent adsorption capacity higher than the other batch. If the other components remain the same, the quality of the concrete that leaves the factory will be different. The analysis of the chemical substances in the mud composition is generally not carried out in the concrete ready-mix plant, and needs to be sent to the laboratory, which is time-consuming and expensive. However, CNS491 or other specifications do not provide a simple and easy way to solve this problem.

Therefore, based on the long-term research and development in the concrete industry, the inventor proposed the methylene blue fast screening method for sand and gravel fine particles of the present invention. This innovative fast screening method not only can quickly know whether the mud content in a batch of fine particles meets the requirements, but also can detect the adsorption of the chemical substances in the interface to the surfactant, which can be used as a reference for the acceptance of the feed.

This paragraph extracts and compiles certain features of the present invention. Other features will be revealed in subsequent paragraphs. Its purpose is to cover the spirit and scope of the additional patent application, various modifications and similar arrangements.

In order to achieve the foregoing objective, the present invention proposes a fast sieve detection method for methylene blue of sand and gravel fines, which includes the steps of: a) disposing a methylene blue solution; b) providing a first fine particle; c) using the first fine particle Take multiple groups of mud powders of different weights and add them to quantitative deionized water respectively to calculate the mud content percentage of each group of mud powder in the corresponding mixed solution; d) Use the methylene blue solution to titrate the mixed solutions to obtain A calibration curve equation and the upper and lower standard deviation range of the calibration curve equation, where the horizontal axis data of the calibration curve equation is the percentage of mud content, and the vertical axis data is the amount of the methylene blue solution titrated on the filter paper when it is saturated; e) Provide a second fine granular material sieved through #200 screen, and determine the percentage of mud content in the second fine granular material; f) take a first amount of the first sieved Add two fine particles to a second amount of water, and drop the mixed liquid on a filter paper; g) Add a third amount of the methylene blue solution to the mixed liquid and stir evenly with a magnet rod for one minute, and take a few drops The mixed solution is dropped on the filter paper; h) if the filter paper titration result is saturated or supersaturated, record a current saturated amount of the methylene blue solution; if the filter paper titration result is unsaturated, repeat step g); and i) if the saturated amount and The corresponding mud content percentage of the mud powder in the second fine aggregate falls within the upper and lower standard deviation range of the calibration curve equation. It is determined that the mud content of the second fine aggregate is close to the mud content of the first fine aggregate. Is acceptable.

According to the present invention, step c) may further include the following sub-steps: c1) washing and sieving the first fine granular material with #200 mesh water; c2) collecting the muddy water after washing and sieving, and letting it stand for precipitation 2~3 Days; c3) Remove the upper clear liquid after the sedimentation layer, and dry the lower sediment at a temperature of 110±5°C to constant weight, and determine its mass to be accurate to 0.1% of the sediment; c4) Dry it After the sample 8g±0.05g, 6.5g±0.05g, 5g±0.05g, 3.5±0.05g, 2±0.05g, add 100g±0.1g of deionized water to form a mixed solution, and stir with a magnet rod Uniform; and c5) Calculate the percentage of mud content of each group of samples in the corresponding mixture.

According to the present invention, step d) may further include the following sub-steps: d1) take a set of obtained mixed solutions and drop a quantitative methylene blue solution into it and continue to stir for three minutes; d2) take a few drops of methylene blue solution and mix Droplets on the filter paper; d3) If saturation occurs on the filter paper, record the amount of methylene blue solution added; if there is unsaturation on the filter paper, drop a quantitative amount of methylene blue solution and continue stirring for one minute, and repeat step d2); d4) Repeat step d1) until the amount of methylene blue solution corresponding to the saturation of all the mixtures is recorded; d5) Take the percentage of mud content as the horizontal axis data, and the amount of methylene blue solution at saturation as the vertical axis data. Perform regression analysis on the experimental data of each group of mixed solution to obtain a calibration curve equation; and d6) calculate the upper and lower standard deviation range of the calibration curve equation and form a boundary line respectively.

In order to achieve the foregoing objective, the present invention also proposes another method for rapid screening of methylene blue in fine sand and gravel, which includes the steps of: a) disposing a methylene blue solution; b) providing a first fine particle; c) determining the first fine particle The sludge content and water content of the washed material in the material; d) The titration result of the first fine granular material with the methylene blue solution is used to obtain a calibration curve equation and a range of 1 ml above and below the calibration curve equation, wherein the calibration curve equation The data on the horizontal axis of the line equation is the percentage of mud content, and the data on the vertical axis is the amount of the methylene blue solution titrated on the filter paper when it is saturated. The calibration curve equation has a fixed empirical regression after several batches of samples from the same first fine particle source. Intercept value, the conversion between percentage of mud content and washing mud content and moisture content into mud content percentage = washing mud content * (1- moisture content); e) Provide one of the first sifting through #200 screen Two fine granules, and determine the percentage of mud content in the second fine granules; f) Take a first quantity of the sieved second fine granules and add a second quantity of water , And drop the mixed liquid on a filter paper; g) Add a third amount of the methylene blue solution to the mixed liquid and stir evenly with a magnet rod for one minute, then drop the mixed liquid on the filter paper; h) If the filter paper is titrated If the result is saturated or supersaturated, record the current saturated dosage of the methylene blue solution; if the filter paper titration result is unsaturated, repeat step g); and i) if the saturated dosage and the corresponding second fine granular material accounted for If the percentage of mud content falls within a range of 1 ml above and below the calibration curve equation, it is determined that the mud content of the second fine aggregate is close to the mud content of the first fine aggregate and is acceptable.

According to the present invention, step c) may further include the following sub-steps: c1) take a first part of the first fine pellets and record a first weight of the first fine pellets of the first part; c2) heating The first fine particles of the first part even contain no moisture, record a second weight at this time; c3) Wash and sieve the first fine particles of the first part with #200 mesh; c4) Wash the sieved fine sand with water until the filtered water is clarified; c5) Heat the fine sand to remove moisture and record a third weight; and c6) Calculate the washing mud content and moisture content, where the washing mud content = second weight-third Weight; moisture content = ((first weight-second weight) / first weight) * 100%.

According to the present invention, step d) may further include the following sub-steps: d1) take a second part of the first fine pellets, and record a fourth weight of the first fine pellets of the second part; d2 ) Add the second part of the first fine particles to a quantitative water to form a mixed liquid, and calculate the percentage of mud content in the mixed liquid according to the fourth weight and the quantitative water weight; d3) In the mixed liquid Add a quantitative amount of methylene blue solution and keep stirring for three minutes; d4) Take a few drops of the mixed solution of methylene blue solution and drop it on the filter paper; d5) If it appears saturated on the filter paper, record the amount of methylene blue solution added; if it appears on the filter paper For unsaturation, add a quantitative amount of methylene blue solution and keep stirring for one minute, and repeat step d4); d6) Take the percentage of mud content as the horizontal axis data, and the amount of methylene blue solution when saturated is the vertical axis data, connect the fixed intercept The point where the value is located to obtain the calibration curve equation; and d7) Calculate the upper and lower 1ml range of the calibration curve equation and form a boundary line respectively.

As described in the two quick-screen detection methods for methylene blue of fine sand and gravel materials, step a) may further include the following sub-steps: a1) provide 5±0.01 g of reagent grade methylene blue; a2) place the reagent grade methylene blue Into a 300±100ml beaker of deionized water and stir with a magnet rod until it is completely dissolved; a3) pour the solution obtained in step a2) into a volumetric flask; and a4) add deionized water to the volumetric flask until the final The solution is 1000ml. The filter paper titration result is unsaturated, which is defined as the methylene blue solution mixed with the mixed solution and then dropped on the filter paper. The methylene blue is adsorbed on the fine particles and does not diffuse to the edge of the filter paper.

The aforementioned first quantitative and the second quantitative are 100g±0.05g, and the third quantitative is 1ml.

In the present invention, the methylene blue solution is used to perform titration test on the fine granular material sample of the specific material source, thereby obtaining the calibration line equation and the allowable range of the fine granular material of the material source, which serve as the basis for subsequent acceptance of the fine granular material of the same source. Compared with the prior art, in addition to saving operation time and reducing the workload of operators, it can also analyze the incoming fine particles as a basis for subsequent interface active agent addition.

The present invention will be described more specifically by referring to the following embodiments.

Please see Fig. 1, which is a flow chart of a fast screening method for detecting methylene blue of fine sand and gravel material according to an embodiment of the present invention. According to the spirit of the present invention, the first step of the fast screening method is to prepare a methylene blue solution (S01) for testing. For the configuration of methylene blue solution, please see Figure 2, which is a flow chart of methylene blue solution configuration. First, provide 5±0.01g reagent grade methylene blue (S011). Next, put the reagent grade methylene blue into a 300±100ml beaker of deionized water and stir with a magnet rod until it is completely dissolved (S012). After that, pour the solution obtained in step S012 into a volumetric flask (S013). It is best to use deionization to rinse the remaining liquid on the beaker into the volumetric flask. Finally, add deionized water to the volumetric flask until the final solution is 1000ml (S014). At this time, the volume molar concentration of the prepared methylene blue solution is about 0.0156 mol/L.

Next, the second step of the fast screening method is to provide a first fine pellet (S02). The sources of the first fine pellets and the second fine pellets mentioned later must be the same, for example from the same source. The first fine pellets are used to set the samples that determine the acceptance criteria, and the second fine pellets refer to the source samples for each subsequent feed test. When the first fine granular material is determined, multiple groups of mud powder with different weights are taken from the first fine granular material and added to quantitative deionized water respectively to calculate the mud content percentage of each group of mud powder in the corresponding mixture ( S03). Regarding this step, it can be subdivided into sub-steps to operate. Please see Figure 3, which is a flowchart of the sub-steps of step S03. First, the first fine particles are washed and sieved with #200 mesh water (S031), and the fine particles remaining on the 200 mesh and filtered water passing through the 200 mesh can be obtained. Then, collect the muddy water that has been washed and sieved, and let it stand for 2~3 days to settle (S032). The purpose of step S032 is to wait for the mud powder in the muddy water to settle. Since the first fine particles from different sources will have different mud content, the physical properties or chemical properties of the mud powder will also be different. Therefore, based on the actual situation of mud sedimentation, it is decided that this step will be carried out for 2 or 3 days (the higher the mud content, the longer it will take). After the sedimentation is separated, the upper clear liquid is removed, and the lower sediment is dried at a temperature of 110±5°C to a constant weight, and its mass is determined to be accurate to 0.1% of the sediment (S033). The dried product will be mud powder that has passed through 200 screens. Thus, take 8g±0.05g, 6.5g±0.05g, 5g±0.05g, 3.5±0.05g, 2±0.05g of the dried sample, and add 100g±0.1g of deionized water to form a mixed solution. Stir evenly with a magnet rod (S034), and calculate the percentage of mud content of each group of samples in the corresponding mixture (S035).

After determining the percentage of each mud content, use the methylene blue solution to titrate the mixtures to obtain a calibration curve equation and the next standard deviation range of the calibration curve equation, where the calibration curve equation horizontal axis data It is the percentage of mud content, and the vertical axis data is the amount of the methylene blue solution titrated on the filter paper when it is saturated (S04). Here, the calibration curve equation is used to judge and accept the standard of the second fine-grained material of the subsequent same material source, and the next standard deviation range is its error range (allowable range). In order to have a better understanding of this, the method of obtaining the calibration curve equation is illustrated by a flowchart, see Figure 4. First, take a set of obtained mixed solutions and drop a quantitative methylene blue solution into it and continue stirring for three minutes (S041), for example, take a mixed solution formed by adding 8g±0.05g sample. Then, take a few drops of the mixed solution of methylene blue solution and drop it on the filter paper (S042), that is, the mixed solution dropped on the filter paper contains deionized water, mud powder and methylene blue, and further analysis is performed on the filter paper. If it appears saturated on the filter paper, record the amount of methylene blue solution added; if it appears unsaturated on the filter paper, drop a quantitative amount of methylene blue solution and continue to stir for one minute, and repeat step S042 (S043). For the description of saturation, unsaturation and possible supersaturation, please see Figure 5. The figure shows the test results of unsaturated, saturated and supersaturated filter paper in sequence from top to bottom. The reason for the unsaturation is that methylene blue is adsorbed by the mud powder or additives in the fine granular material, and will not diffuse as the deionized water diffuses outside the titration area. In the subsequent testing of the second fine-grained material, the occurrence of unsaturation means that the material source remains unchanged, but the mud content has increased; or the material source has changed. At this time, it is necessary to increase the amount of interface active agent, otherwise the viscosity of the concrete using the fine-grained material will increase. It can be said that the definition of unsaturation is that the methylene blue solution is mixed with the mixed solution and then dropped on the filter paper, and the methylene blue is adsorbed on the fine particles and does not diffuse to the edge of the filter paper. The reason for the saturation phenomenon is that although methylene blue is absorbed by the mud powder or additives in the fine particles, it is in the limit state. If the amount of methylene blue is increased, the methylene blue will diffuse from the titration area to the outside. At this time, there will be a faint blue halo around the titration area, but it is not very obvious. In the subsequent test of the second fine-grained material, the occurrence of saturation means that the material source remains unchanged and the mud content is also stable. The reason for the supersaturation phenomenon is that although the methylene blue is partially adsorbed by the mud powder or additives in the fine particles, the other part is not. These methylene blue will diffuse from the titration area to the outside, forming a clear blue halo, and continue to change Deeper. In the subsequent testing of the second fine-grained material, the occurrence of supersaturation means that the material source remains unchanged, but the mud content has increased; or the material source has changed. At this time, it is necessary to reduce the amount of interface active agent, otherwise the viscosity of the concrete using the fine-grained material will change.

The fourth step of the method of obtaining the calibration curve equation is to repeat step S041 until the amount of methylene blue solution corresponding to the saturation of all the mixtures is recorded (S044), which means that the mud content of 6.5g±0.05g, 5g is completed in sequence Each group of ±0.05g, 3.5±0.05g and 2±0.05g. Next, take the percentage of mud content as the horizontal axis data and the amount of methylene blue solution when saturated as the vertical axis data, and perform regression analysis on the experimental data of each group of mixed solutions obtained before this step to obtain a calibration curve equation (S045). An example is shown in Figure 6. Figure 6 The black point data source (material source) is a certain area of fine grains. The calibration curve equation is shown as the dotted line in the figure. The square of the distance between the straight line and each data point shown in the calibration curve equation is the smallest. Finally, calculate the upper and lower standard deviation range of the calibration curve equation, and form a boundary (S046). As shown in Figure 6, there is a boundary line on the upper and lower sides of the calibration curve equation, and the interval formed between the two lines is the acceptable range of the mud content of the second fine particles.

The fifth step of the fast sieve detection method for methylene blue of sand and gravel fines is to provide one of the second fines sieved through the #200 screen and determine the percentage of mud content in the second fines. (S05). As mentioned above, the second fine pellets and the first fine pellets are materials of the same source and different batches, and the second fine pellets should be checked according to the inspection standard set by the first fine pellets to see if its mud content is the same To accept. The percentage of mud content can be determined by recording the original weight of the second fine granular material, the weight after heating (without water) and the weight of the mud after sieving. The second fine particles need to be stirred evenly. Then, take a first amount of the sieved second fine particles into a second amount of water, and drop the mixed liquid on a filter paper (S06). The first quantitative and the second quantitative can be any suitable operating weights. According to the present invention, both the first quantitative and the second quantitative can be 100g±0.05g. Then, add a third amount of the methylene blue solution to the mixed solution and stir evenly with a magnet rod for one minute, and drop a few drops of the mixed solution on the filter paper (S07). In practice, the third quantity can be used without too much, such as 1ml. If the filter paper titration result is saturated or supersaturated, record the current saturated amount of the methylene blue solution; if the filter paper titration result is unsaturated, repeat step S07 (S08). In other words, if the first titration reaches saturation or supersaturation, the current amount of methylene blue is sufficient. If it is not saturated, add 1ml of methylene blue solution to the mixture each time, and continue filter paper titration until the filter paper titration result is saturated or supersaturated. Mark the data points of the percentage of mud content and the amount of methylene blue on the axis of the calibration curve equation. Finally, if the saturated amount and the corresponding percentage of the mud content in the second fine aggregate fall within the upper and lower standard deviation of the calibration curve equation, it is determined that the mud content of the second fine aggregate is close to the first The sludge content of the fine particles is acceptable (S09). For an explanation of this point, please refer to Figure 6. Open circles and solid asterisks respectively indicate the test results of two different second fine particles. It can be seen from Fig. 6 that the hollow dot falls within the upper and lower standard deviation range of the calibration curve equation, so the mud content of the second fine particles is close to the mud content of the first fine particles and is acceptable. Conversely, if the solid asterisk falls outside the last standard deviation range, it means that the batch of fine-grained materials either contains too much mud or contains many components that may increase the viscosity of the concrete. Either check it out, or increase the interface active agent to improve the batch of feed.

The methylene blue fast screening method for sand and gravel fine particles introduced above is a standard method. Although it is faster than the conventional method for detecting mud content, it still requires concrete pre-mix plant staff to spend a certain amount of time to deal with it. Considering the limitations of the equipment in the ready-mixed concrete plant and the operability of the personnel, the present invention also provides a fast method for detecting methylene blue of fine sand and gravel materials. Please refer to the following description.

Please refer to Fig. 7, which is a flowchart of another method for rapid sieve detection of methylene blue of fine sand and gravel material (quick mode) according to an embodiment of the present invention.

The first step of the quick mode, as in the standard mode, is to configure a methylene blue solution (S11), which will not be repeated here. The second step is to provide a first fine pellet (S12). Next, the water-washed mud content and water content in the first fine pellets are determined (S13). In order to have a further understanding of this step, please refer to Figure 8, which is a flow chart for obtaining the mud content and moisture content of washing.

First, take a first part of the first fine pellets and record a first weight of the first part of the first fine pellets (S131). The present invention limits the first weight, which can range from tens of g to 200 g in practice, depending on the on-site experimental equipment. Next, heat the first fine particles of the first part to be free of moisture, record a second weight at this time (S132), and wash and sieve the first fine particles of the first part with #200 mesh water (S133 ), wash the unscreened fine sand until the filtered water is clear (S134), and record a third weight after heating the fine sand to remove moisture (S135). So far, the first weight, second weight, and third weight for calculation are obtained. Finally, calculate the mud content and moisture content of the washing, where the mud content of the washing = the second weight-the third weight; the moisture content = ((the first weight-the second weight) / the first weight) * 100% (S136).

The fourth step of the quick way is to use the titration result of the methylene blue solution on the first fine particles to obtain a calibration curve equation and a range of 1 ml above and below the calibration curve equation, wherein the calibration curve equation horizontal axis data Is the percentage of mud content, the vertical axis data is the amount of the methylene blue solution titrated on the filter paper when it is saturated, the calibration curve equation has a fixed intercept value after empirical regression of several batches of samples from the same first fine particle source, containing The conversion between mud content percentage, washed mud content and water content is converted into mud content percentage = washed mud content*(1-water content) (S14). For the production of the calibration curve equation and the upper and lower ranges, please refer to the flowchart shown in Figure 9.

First, take a second part of the first fine pellets, and record a fourth weight of the first fine pellets of the second part (S141). The aforementioned fourth weight is not limited by the present invention, but can be several tens of g to 200 g according to different field experiment equipment. Then, the second part of the first fine pellets is added to a quantitative water to form a mixed liquid, and the mud content percentage in the mixed liquid is calculated according to the fourth weight and the quantitative water weight (S142). Quantitative water weight, such as 100g. Drop a quantitative amount of methylene blue solution into the mixed solution and continue stirring for three minutes (S143). Take a few drops of the mixed solution of methylene blue solution and drop it on the filter paper (S144). If the filter paper is saturated, record the amount of added methylene blue solution. Dosage: If there is unsaturation on the filter paper, drop a quantitative methylene blue solution and keep stirring for one minute, and repeat step S144 (S145). Step S145 is the same as step S043 of the previous embodiment, increasing the amount of methylene blue to find the saturation point. Next, take the percentage of mud content as the horizontal axis data, and the amount of methylene blue solution when it is saturated as the vertical axis data, and connect the points of the fixed intercept value to obtain the calibration curve equation (S146). A schematic example is shown in Figure 10. The calibration curve equation (straight line) is drawn with a dashed line, and the two end points formed are the data points (solid circles) of the percentage of mud content and the amount of methylene blue solution at saturation (solid circles), and the points where the fixed intercept value is (hollow circles) . It should be emphasized that the fixed intercept value is the empirical value found after many experiments with the same source of fine particles in the laboratory. Although each source is different, it maintains a fixed value for the same source. . Finally, calculate the upper and lower 1ml range of the calibration curve equation, and form a boundary (S147). In other words, the vertical axis data corresponding to each horizontal axis data of the upper and lower boundary lines (solid lines) in Fig. 10 are 1ml larger or 1ml smaller than the vertical axis data of the corresponding calibration curve equation.

The fifth step to the eighth step of the quick way are basically the same as the steps S05 to S07 of the previous embodiment: provide one of the second fine particles sieved through a #200 screen, and determine the mud powder in the second fine particles The percentage of mud content (S15), take a first amount of the second fine particles after sieving into a second amount of water, and drop the mixed liquid on a filter paper (S16), add Add a third amount of the methylene blue solution to the mixed solution and stir evenly for one minute with a magnet rod, drop the mixed solution on the filter paper (S17) and if the filter paper titration result is saturated or supersaturated, record the current amount of the methylene blue solution Saturated dosage; if the result of filter paper titration is unsaturated, repeat step S17 (S18). The operation purpose and quantitative value of this embodiment are the same as those of the previous embodiment, and will not be repeated here. Finally, if the saturated amount and the corresponding percentage of the mud content in the second fine aggregate fall within the range of 1 ml above and below the calibration curve equation, it is determined that the mud content of the second fine aggregate is close to the first The sludge content of the fine particles is not acceptable (S19). As mentioned above, as long as the subsequent test results of the second fine pellets from the same source can fall within the upper and lower boundaries of Figure 10, the batch of fine pellets can be accepted. Compared with the standard method, the fast method only needs a set of test data to simplify the acquisition of the calibration curve equation, but the acquisition of the set of test data must be very accurate.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the relevant technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, The protection scope of the present invention shall be subject to those defined by the attached patent application scope.

no

Figure 1 is a flow chart of a fast screening method for detecting methylene blue of fine sand and gravel material according to an embodiment of the present invention, Figure 2 is a flow chart of the configuration of methylene blue solution, Figure 3 is a flow chart of sub-steps of step S03 of the fast screening method, Figure 4 In order to obtain the flow chart of the calibration curve equation, Figure 5 shows the test results of unsaturated, saturated and supersaturated filter paper in sequence from top to bottom. Figure 6 shows an example of the calibration curve equation for a source, and Figure 7 shows According to an embodiment of the present invention, another method for rapid screening of methylene blue in fine sand and gravel is shown. Figure 8 is a flow chart for obtaining the mud content and water content of washing. Figure 9 is a calibration curve equation and upper and lower ranges. Fig. 10 shows an example of the calibration curve equation for a material source.

Claims (5)

A fast screening method for detecting methylene blue of fine sand and gravel material, comprising the steps of: a) configuring a methylene blue solution; b) providing a first fine particle; c) taking multiple groups of mud powder with different weights from the first fine particle Add 100g±0.1g of deionized water to calculate the percentage of mud content of each group of mud powder in the corresponding mixture; d1) Take a set of mixtures and gradually add methylene blue solution to it, and after adding methylene blue solution Perform filter paper chromatography and record the amount of methylene blue solution added when the filter paper is saturated; d2) Repeat step d1) until the amount of methylene blue solution corresponding to the saturation of all the mixed solutions is recorded; d3) Take the percentage of mud content as Data on the horizontal axis, the amount of methylene blue solution used when saturated is the data on the vertical axis. Perform regression analysis on the experimental data of each group of mixed solutions obtained before this step to obtain a calibration curve equation; d4) Calculate the next standard deviation of the calibration curve equation Range and form a boundary respectively; e) Provide a second fine granular material sieved through #200 screen, and determine the percentage of mud content in the second fine granular material; f) Take a first A certain amount of the sieved second fine particles is added to a second amount of water, and the mixed liquid is dropped on a filter paper; g) a third amount of the methylene blue solution is added to the mixed liquid and Stir the magnet rod uniformly for one minute, and drip the mixture on the filter paper; h) if the filter paper titration result is saturated or supersaturated, record a current saturated amount of the methylene blue solution; if the filter paper titration result is unsaturated, repeat step g); and i) If the saturated amount and the corresponding percentage of mud content in the second fine aggregate fall within one standard deviation of the calibration curve equation, it is determined that the mud content of the second fine aggregate is close to the first The sludge content of the fine particles is acceptable. Among them, the filter paper titration result is unsaturated, which is defined as the methylene blue solution mixed with the mixed liquid and then dropped on the filter paper. The methylene blue is adsorbed on the fine particles and does not diffuse to the edge of the filter paper. A blue halo is formed around the methylene blue titration area, at this time the filter paper titration result is defined as saturation; if the blue halo formed around the methylene blue titration area continues to grow larger and deeper, the filter paper titration result is defined as supersaturated at this time, the first quantitative 100g±0.05g , The second quantitative is 100g±0.05g, and the third quantitative is 1ml. As described in item 1 of the scope of patent application, the methylene blue fast screening method for sand and gravel fine particles, wherein step c) further comprises the following sub-steps: c1) the first fine particles are washed and sieved with #200 mesh; c2 ) Collect the muddy water after washing and sieving, and let it stand for 2~3 days for sedimentation; c3) After sedimentation, remove the upper clear liquid, and dry the lower sediment at a temperature of 110±5℃ to a constant weight. The quality is accurate to 0.1% of the sediment; c4) Take the dried sample 8g±0.05g, 6.5g±0.05g, 5g±0.05g, 3.5±0.05g, 2±0.05g, and add 100g±0.1 respectively g of deionized water to form a mixed solution, and stir evenly with a magnet rod; and c5) Calculate the mud content percentage of each group of samples in the corresponding mixed solution. A fast screening method for detecting methylene blue of fine sand and gravel material, comprising the steps of: a) configuring a methylene blue solution; b) providing a first fine granular material; c) determining the water-washed mud content and water content in the first fine granular material ； d1) Take a second part of the first fine pellets, and record a fourth weight of the first fine pellets of the second part; d2) Add a quantitative amount of water to the first fine pellets of the second part To form a mixed solution, and calculate the percentage of mud content in the mixed solution according to the fourth weight and quantitative water weight; d3) Gradually add methylene blue solution to the mixed solution, and perform filter paper color analysis after adding the methylene blue solution , Record the amount of methylene blue solution added when the filter paper is saturated; d4) Take the percentage of mud content as the horizontal axis data, and the amount of methylene blue solution when saturated is the vertical axis data, connect a fixed intercept value to obtain a calibration Line equation; d5) Calculate the upper and lower 1ml range of the calibration line equation, and form a boundary line respectively, where the calibration line equation has the fixed intercept value after empirically regression of several batches of samples from the same first fine particle source , The conversion between the percentage of mud content and the mud content and moisture content of washing is converted into percentage of mud content = washing mud content*(1-moisture content); e) Provide one of the second fine particles sieved by #200 screen And determine the percentage of mud content in the second fine granular material; f) take a first quantity of the sieved second fine granular material and add it to a second quantity of water, and add The mixed liquid is dropped on a filter paper; g) a third amount of the methylene blue solution is added to the mixed liquid and uniformly stirred with a magnet rod for one minute, and the mixed liquid is dropped on the filter paper; h) if the filter paper titration result is saturated or If it is oversaturated, record the current saturated amount of the methylene blue solution; if the filter paper titration result is unsaturated, repeat step g); and i) If the saturated amount and the corresponding percentage of mud content in the second fine aggregate fall within the range of 1 ml above and below the calibration curve equation, it is determined that the mud content of the second fine aggregate is close to the first The sludge content of the fine particles is acceptable. Among them, the filter paper titration result is unsaturated, which is defined as the methylene blue solution mixed with the mixed liquid and then dropped on the filter paper. The methylene blue is adsorbed on the fine particles and does not diffuse to the edge of the filter paper. A blue halo is formed around the methylene blue titration area, at this time the filter paper titration result is defined as saturation; if the blue halo formed around the methylene blue titration area continues to grow larger and deeper, the filter paper titration result is defined as supersaturated at this time, the first quantitative 100g±0.05g , The second quantitative is 100g±0.05g, and the third quantitative is 1ml. As described in item 3 of the scope of patent application, the methylene blue fast screening method for sand and gravel fine particles, wherein step c) further includes the following sub-steps: c1) take a first part of the first fine particles and record the first part A first weight of the first fine pellets; c2) Heat the first part of the first fine pellets so that they do not contain moisture, and record a second weight at this time; c3) Wash and sift the first fine pellets with #200 mesh water The first fine granular material of the first part; c4) Wash the unsieved fine sand until the filtered water is clear; c5) Heat the fine sand to remove water and record a third weight; and c6) Calculate the mud content of the washed water and Moisture content, where mud content in water washing = second weight-third weight; moisture content = ((first weight-second weight) / first weight) * 100%. As described in item 1 or item 3 of the scope of patent application, the method for detecting methylene blue of fine sand and gravel, wherein step a) further includes the following sub-steps: a1) providing 5±0.01 g of reagent grade methylene blue; a2) Put the reagent grade methylene blue into a 300±100ml beaker of deionized water and stir with a magnet rod until it is completely dissolved; a3) Pour the solution obtained in step a2) into a volumetric flask; and a4) add it Ion water is put into the volumetric flask until the final solution is 1000ml.

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