Device for detecting calcium oxide in slaked lime and application thereof

Abstract

The invention provides a device for detecting calcium oxide in slaked lime and application thereof. The device comprises a display screen, a controller, a reaction container, a temperature probe and an operation panel. The controller is electrically connected with the operation panel, the temperature probe and the display screen. The application method comprises the following steps: calcining calcium oxide at 580 DEG C, putting calcium oxide and calcium hydroxide with gradient concentrations into a reaction container, detecting the temperature by using a temperature probe, and drawing a calcium oxide content standard curve; placing a sample to be detected in the reaction container, recording temperature change data t1, and calculating the corresponding calcium oxide content according to the calcium oxide content standard curve. The influence of calcium hydroxide content detection is eliminated by accurately detecting the calcium oxide content in the slaked lime, so that the accuracy of the calcium hydroxide content detection structure in the slaked lime is ensured, and the problem of high calcium hydroxide content detection data caused by the existence of calcium oxide when the calcium hydroxide content is detected by adopting a sucrose method is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical detection, and in particular relates to a device for detecting calcium oxide in slaked lime and application thereof. Background Art

[0002] Industrial slaked lime, also known as slaked lime or calcium hydroxide, has a chemical formula of Ca(OH) 2 It is a white powdery solid. It is usually prepared by limestone calcination method. Limestone is calcined into calcium oxide (quicklime), and then screened, digested (reacted with water), purified, separated, deslagging, centrifugal dehydration and dried to obtain slaked lime. Slaked lime is widely used in industry. In wastewater treatment, slaked lime is often used as a neutralizer to remove acidic substances and heavy metal ions in water. At the same time, it can also be used for flue gas desulfurization to effectively remove pollutants such as sulfur dioxide in flue gas. The calcium hydroxide content of slaked lime is mainly determined by sucrose method. The principle is that calcium hydroxide has very low solubility in water. After adding sucrose solution, it can be made into sucrose calcium with high solubility. Then, the content of calcium hydroxide in sucrose calcium is titrated with acid. The test solution uses phenolphthalein as an indicator and is titrated with hydrochloric acid standard titration solution until colorless. Since calcium oxide may exist due to incomplete digestion during the preparation of calcium hydroxide, the test result is high when the calcium hydroxide content is measured by sucrose method.

[0003] There is no standard method for the detection of calcium oxide in slaked lime. In the industry standard HG / T 4120-2009, calcium hydroxide has very low solubility in water. After adding sucrose solution, it can be made into sucrose calcium with high solubility. Then the content of calcium hydroxide in sucrose calcium is titrated with acid. The test solution uses phenolphthalein as an indicator and is titrated with hydrochloric acid standard titration solution until it is colorless. Because in the detection process of this method, calcium hydroxide and calcium oxide in slaked lime are reacted with hydrochloric acid, the converted calcium oxide is included in the calcium hydroxide content detection data, resulting in a high calcium hydroxide content. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies in the prior art, provide a device for detecting calcium oxide in slaked lime and its application, establish a method for detecting the calcium oxide content in slaked lime through a temperature rise experiment, eliminate the influence of calcium hydroxide content detection by accurately detecting the calcium oxide content in slaked lime, thereby ensuring the accuracy of the calcium hydroxide content detection structure in slaked lime.

[0005] In order to solve the above technical problems, the present invention provides a device for detecting calcium oxide in slaked lime, the device comprising: a display screen 3, a controller 4, a reaction container 5, a temperature probe 6, and an operation panel 7; the controller 4 is electrically connected to the operation panel 7, the temperature probe 6, and the display screen 3 respectively.

[0006] The above device further includes a shell 1 , the temperature probe 6 is arranged in the shell 1 , and the display screen 3 , the controller 4 and the operation panel 7 are arranged on the surface of the shell 1 .

[0007] The above device further includes a temperature measuring tank 2 , which is arranged in the housing 1 , and a temperature probe 6 is fixed in the temperature measuring tank 2 .

[0008] The above device further comprises an ultrasonic generating element 8 provided on the outer wall of the temperature measuring chamber 2 , and the ultrasonic generating element 8 is electrically connected to the controller 4 .

[0009] In the above device, further, the reaction container 5 includes a tank body 51, a cover body 52 and a hollow tube 53, the hollow tube 53 is arranged on the cover body 52, the cover body 52 covers the opening of the tank body 51, and the hollow tube 53 is suspended in the tank body 51.

[0010] Based on a general technical concept, the present invention provides an application of the device in detecting calcium oxide in slaked lime, and the application method comprises: S1. Calcium oxide is calcined at 580°C. Calcium oxide and calcium hydroxide with gradient concentrations are placed in a reaction vessel 5. The temperature is detected by a temperature probe 6. S2. Draw a standard curve of calcium oxide content; S3. Place the sample to be tested in the reaction container 5, record the temperature change data △t1, and calculate the corresponding calcium oxide content according to the calcium oxide content standard curve.

[0011] In the above application, further, in S2, the calcium oxide content standard curve is: y = 0.018△t, Among them, y is the calcium oxide content, the unit is %; △t is the temperature change data of the solution before and after the experiment.

[0012] Compared with the prior art, the advantages of the present invention are: (1) The present invention provides a detection device for detecting calcium oxide in slaked lime, which is easy and quick to operate and can quickly and accurately detect the content of calcium oxide in slaked lime.

[0013] (2) The present invention provides a method for detecting calcium oxide in slaked lime. By using the principle of heat release from the dissolution of calcium oxide, different ratios of calcium oxide and calcium hydroxide are mixed for detection, and a standard curve is established to accurately detect the content of calcium oxide in slaked lime. By detecting the accurate content of calcium oxide, the problem of high calcium hydroxide content detection data due to the presence of calcium oxide when using the sucrose method to detect the content of calcium hydroxide is avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to make the purpose, technical solution and advantages of the embodiments of the present invention more clear, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0015] Figure 1 The present invention is a schematic diagram of the structure of a device for detecting the calcium oxide content in slaked lime; in the figure: 1, shell; 2, temperature measuring tank; 3, display screen; 4, controller; 5, reaction container; 51, tank body; 52, cover body; 53, hollow tube; 6, temperature probe; 7, operation panel; 8, ultrasonic generating element.

[0016] Figure 2 This is the electrical connection diagram of the calcium oxide detection device in slaked lime.

[0017] Figure 3 This is a flow chart for the detection of calcium oxide in slaked lime. DETAILED DESCRIPTION

[0018] The present invention is further described below in conjunction with specific preferred embodiments, but the protection scope of the present invention is not limited thereby.

[0019] The materials, reagents and instruments used in the following examples can all be purchased from commercial channels. The experimental methods in the following examples are all conventional methods in the art unless otherwise specified.

[0020] the term Standard curve: A standard curve is a numerical curve of a property obtained by measuring a certain physical and chemical property of a series of standard substances with known components. In analytical chemistry experiments, the standard curve method is often used for quantitative analysis. Usually, the standard working curve is a straight line.

[0021] Example 1 A device for detecting calcium oxide in slaked lime of the present invention, see Figure 1 , including: a display screen 3, a controller 4, a reaction container 5, a temperature probe 6, and an operation panel 7.

[0022] See also Figure 2 , the controller 4 is electrically connected to the operation panel 7, the temperature probe 6, and the display screen 3. After the sample to be tested is added to the reaction container 5, the power of the detection device is turned on, the temperature of the reaction container 5 is detected by the temperature probe 6 and transmitted to the controller 4, and the controller 4 transmits the acquired temperature data to the display screen 3, and records the temperature change data △t of the mixed solution in the reaction container 5.

[0023] Further, in order to better fix the device, the display screen 3, the controller 4, the reaction container 5, the temperature probe 6, and the operation panel 7 are fixed in the housing 1, wherein the temperature probe 6 is arranged in the housing 1, so as to better fix the temperature probe 6. The display screen 3, the controller 4, and the operation panel 7 are arranged on the surface of the housing 1, so as to more conveniently control the device and view the displayed content.

[0024] Furthermore, an ultrasonic generating element 8 is provided on the outer wall of the temperature measuring tank 2, and the ultrasonic generating element 8 is electrically connected to the controller 4. By starting the ultrasonic generating element 8 through the controller 4, the mixing and reaction of the lime and water in the reaction container 5 can be accelerated.

[0025] Furthermore, a temperature measuring tank 2 is provided in the shell 1, a temperature probe 6 is fixed in the temperature measuring tank 2, and an ultrasonic generating element 8 is provided on the outer wall of the temperature measuring tank. When the reaction container 5 is placed in the temperature measuring tank 2, the temperature probe 6 can better detect the temperature of the reaction container 5.

[0026] Furthermore, the reaction container 5 includes a tank body 51, a cover body 52 and a hollow tube 53; the hollow tube 53 is arranged on the cover body 52, and the cover body 52 covers the opening of the tank body 51 to seal the substance in the tank body 51, and the hollow tube 53 is suspended in the tank body 51. After adding the sample to be tested into the tank body 51, the cover body 52 is covered, and the reaction container 5 is placed upside down in the temperature measuring tank 2, and the temperature probe 6 arranged in the temperature measuring tank 2 is inserted into the hollow tube 53. The temperature probe 6 can detect the temperature of the mixed solution in the reaction container 5 more accurately.

[0027] Example 2 An application of the detection device of Example 1 in detecting calcium oxide in slaked lime, the detection process thereof is shown in Figure 3 , specifically including the following steps: (1) Preparation of standard chemicals: Calcium hydroxide is of high purity, and calcium oxide is of high purity. Calcinated at 580°C, the mixture is transferred to a dryer for cooling.

[0028] (2) Drawing of the standard curve: Take high-grade pure calcium hydroxide and prepared calcium oxide and mix them to prepare standard samples with gradient concentrations.

[0029] Standard sample 1: 4.9 g calcium hydroxide + 0.1 g calcium oxide, calcium oxide content 2%; Standard sample 2: 4.8 g calcium hydroxide + 0.2 g calcium oxide, calcium oxide content 4%; Standard sample 3: 4.6g calcium hydroxide + 0.4g calcium oxide, calcium oxide content 8%; Standard sample 4: 4.5 g calcium hydroxide + 0.5 g calcium oxide, calcium oxide content 10%; Standard sample 5: 4.0g calcium hydroxide + 1.0g calcium oxide, calcium oxide content 20%.

[0030] The above standard sample is placed in the reaction container 5, and the reaction container 5 is placed in the detection device of Example 1. The power of the detection device is turned on, and the temperature of the reaction container 5 is detected by the temperature probe 6 and transmitted to the controller 4. The controller 4 transmits the acquired temperature data to the display screen 3, and records the temperature change data △t on the display screen 3. Arrange the data, and draw a standard curve of calcium oxide according to the detection data: y=a△t+b. Wherein y is the calcium oxide content, in units of %; △t is the temperature change data of the solution before and after the experiment, that is, the temperature after the reaction minus the temperature before the reaction.

[0031] In this embodiment, the standard curve of calcium oxide content is y= 0.018Δt.

[0032] (3) Detection of the sample to be tested: Add 10 ml of water to the tank 51, add 5 g of the slaked lime sample to be tested, quickly cover the cover 52, shake to mix, invert the reaction container 5 in the temperature measuring tank 2, turn on the power of the detection device, use the temperature probe 6 to detect the temperature of the reaction container 5 and transmit it to the controller 4, and the controller 4 transmits the acquired temperature data to the display screen 3. After the reaction is completed, record the temperature change data △t1, and calculate the corresponding calcium oxide content y1 according to the calcium oxide content standard curve y= 0.018△t, which can be converted into molar concentration according to the sample amount.

[0033] (4) Conversion of calcium hydroxide content: If you need to obtain the calcium hydroxide content in slaked lime, take 5 g of slaked lime sample, convert the calcium in it into sucrose calcium with greater solubility, and then use phenolphthalein as an indicator and titrate with hydrochloric acid standard titration solution until the end point is colorless. The result of this method is converted into the molar concentration of calcium. The molar concentration of calcium oxide measured in the above sample is subtracted from the result to obtain the molar concentration of calcium hydroxide in slaked lime. The accurate content of calcium hydroxide in slaked lime can be obtained by conversion.

[0034] Experiment 1: Detect the content of calcium oxide in actual samples.

[0035] Add 10 ml of water to the tank 51, add 5 g of slaked lime sample, quickly cover with lid 52, shake to mix, and place the reaction container 5 upside down in the temperature measuring tank 2. After the reaction is completed, record the temperature change data of 1.3°C. According to the standard curve of calcium oxide content y=0.018x, the corresponding calcium oxide content is calculated to be 2.34%, i.e., 0.117 g, which can be converted into a molar concentration of 0.002 mol according to the sample amount.

[0036] Take 5 g of slaked lime sample, convert the calcium in it into sucrose calcium with greater solubility, then use phenolphthalein as an indicator and titrate with hydrochloric acid standard titration solution until the end point is colorless. The calcium hydroxide content in the sample is detected to be 95% (0.064 mol).

[0037] Subtract the molar concentration of calcium oxide measured in the above sample (0.002) from the result to get the molar concentration of calcium hydroxide in slaked lime (0.0062). The exact content of calcium hydroxide in slaked lime is 91.8%. Experiment 2: Verify the accuracy of the method in Example 2.

[0038] Take 4.8 g of the above-mentioned slaked lime sample, add 0.2 g of calcium oxide and mix, pour into the tank 51 with 10 ml of water, quickly cover with the cover 52, shake to mix, and place the reaction container 5 upside down in the temperature measuring tank 2. After the reaction is completed, record the temperature change data of 3.4°C, and calculate the corresponding calcium oxide content of 6.12% or 0.306 g based on the calcium oxide content standard curve y=0.018x.

[0039] The actual calcium oxide content in the sample is 0.317 g (0.117+0.2), with a deviation of 3.5%. From the above results, it can be seen that the method of Example 2 of the present invention has high accuracy.

[0040] The above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as above in the preferred embodiment, it is not used to limit the present invention. Any technician familiar with the art can make many possible changes and modifications to the technical solution of the present invention by using the methods and technical contents disclosed above without departing from the spirit and technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention, still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A device for detecting calcium oxide in slaked lime, characterized in that: The device comprises: a display screen (3), a controller (4), a reaction container (5), a temperature probe (6), and an operation panel (7); the controller (4) is electrically connected to the operation panel (7), the temperature probe (6), and the display screen (3), respectively.

2. The device according to claim 1, characterized in that The device further comprises a housing (1), the temperature probe (6) being arranged inside the housing (1), and the display screen (3), the controller (4) and the operation panel (7) being arranged on the surface of the housing (1).

3. The device according to claim 1, characterized in that The device further comprises a temperature measuring tank (2), wherein the temperature measuring tank (2) is arranged in the housing (1), and a temperature probe (6) is fixed in the tank of the temperature measuring tank (2).

4. The device according to claim 3, characterized in that An ultrasonic generating element (8) is provided on the outer wall of the temperature measuring tank (2), and the ultrasonic generating element (8) is electrically connected to the controller (4).

5. The device according to claim 1, characterized in that The reaction container (5) comprises a tank body (51), a cover body (52) and a hollow tube (53); the hollow tube (53) is arranged on the cover body (52); the cover body (52) is used to cover the opening of the tank body (51); and the hollow tube (53) is suspended in the tank body (51).

6. Use of the device according to any one of claims 1 to 5 in detecting calcium oxide in slaked lime, characterized in that: The method of application includes: S1. Calcium oxide is calcined at 580°C. Calcium oxide and calcium hydroxide with gradient concentrations are placed in a reaction container (5). The temperature is detected by a temperature probe (6). S2. Draw a standard curve of calcium oxide content; S3. Place the sample to be tested in a reaction container (5), record the temperature change data △t1, and calculate the corresponding calcium oxide content according to the calcium oxide content standard curve.

7. The use according to claim 6, characterized in that: In the S2, the calcium oxide content standard curve is: y = 0.018△t, Among them, y is the calcium oxide content, the unit is %; △t is the temperature change data of the solution before and after the experiment.

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