Flask applied to distillation separation nitrogen measurement, distillation separation nitrogen measurement device and method

Abstract

The invention discloses a flask applied to distillation separation nitrogen measurement and a distillation separation nitrogen measurement device and method.The flask applied to distillation separation nitrogen measurement comprises a flask body, a guide pipe, a first connecting pipe and a diameter expanding part are arranged at a bottle neck, the diameter of the top of the guide pipe is the same as that of the bottle neck, and the bottom of the guide pipe is located at the bottom of the flask; a connecting opening of the first connecting pipe and the bottle neck is located above the guide pipe, the diameter expanding part is located below the top of the guide pipe, and the diameter expanding part is further provided with a second connecting pipe capable of being communicated with the outer side of the flask body. The flask with a special structure is adopted as a reaction device, in the sample detection process, waste liquid can be automatically sucked back into the waste liquid bottle, the device does not need to be frequently disassembled and assembled, and subsequent sample nitrogen content detection can be carried out.

Description

Technical Field

[0001] The invention relates to the technical field of analysis and testing, in particular to a flask used for distillation separation and nitrogen measurement, a distillation separation and nitrogen measurement device and a method. Background Art

[0002] Steel enterprises use a large amount of vanadium-nitrogen alloys and aluminum slag balls, and their nitrogen content is directly related to the quality of molten steel. Usually, the nitrogen content of vanadium-nitrogen alloys used by steel enterprises is 13-18%, and the nitrogen content of aluminum slag balls is 0-3%. The main principle of the method for detecting nitrogen content is to decompose the powdered raw materials in a sulfur-phosphorus mixed acid medium to obtain a diluted decomposition liquid, in which the nitrogen in the raw materials forms ammonium salts with the acid solution after dilution reaction. Under the action of excess alkali, the generated nitrogen is distilled and separated along with water vapor, and the vapor is condensed to form ammonia water. The ammonia water is absorbed with a boric acid solution and titrated with a standard aminosulfonic acid titration solution to calculate the percentage of nitrogen.

[0003] However, the applicant discovered during the nitrogen measurement process that the nitrogen measurement device has a great impact on the accuracy and efficiency of the nitrogen measurement method. In view of this, the present invention is proposed. Summary of the invention

[0004] The purpose of the present invention is to provide a flask used for distillation separation and nitrogen measurement and a distillation separation and nitrogen measurement method, so as to overcome the problem of low nitrogen measurement efficiency in the prior art.

[0005] The present invention is achieved in that:

[0006] In a first aspect, the present invention provides a flask for distillation separation and nitrogen measurement, comprising a flask body, wherein a conduit, a first connecting tube and an expansion portion are arranged at the bottleneck, the top of the conduit has the same diameter as the bottleneck, and the bottom is located at the bottom of the flask; the connection port between the first connecting tube and the bottleneck is located above the conduit, the expansion portion is located below the top of the conduit, and the expansion portion is further provided with a second connecting tube capable of communicating with the outside of the flask body.

[0007] In a second aspect, the present invention provides a distillation separation nitrogen measurement device, comprising: a water vapor generating device, a waste liquid bottle, the flask described in the above embodiment, a nitrogen determination ball, a condensing device and a distillate receiving bottle connected in sequence by pipelines.

[0008] In an optional embodiment, the water vapor generating device comprises a container for containing water and a heating device for heating the water in the container.

[0009] In an optional embodiment, a water vapor outlet is provided at the top of the water vapor generating device, and the horizontal distance between the water vapor outlet and the water vapor inlet of the waste liquid bottle is 19-21 cm, the vertical distance is 5-6 cm, and the pipe diameter is 0.8-1.2 cm.

[0010] In an optional embodiment, the horizontal distance between the outlet of the waste liquid bottle and the inlet of the first connecting tube of the flask is 17-19 cm, the vertical distance is 4-5 cm, and the diameter of the tube is 0.8-1.2 cm.

[0011] In an optional embodiment, the horizontal distance between the gas outlet of the flask and the highest point of the nitrogen determination ball is 21-23 cm, the vertical distance is 7-8 cm, and the diameter of the pipeline between the flask and the nitrogen determination ball is 0.8-1.2 cm.

[0012] In an optional embodiment, the nitrogen determination ball is a double-ball nitrogen determination ball.

[0013] In a third aspect, the present invention provides a method for measuring nitrogen by distillation separation, comprising:

[0014] The water vapor generating device is started, so that the water vapor passes through the waste liquid bottle, the flask containing the reaction liquid, and the nitrogen determination ball in sequence, and then is condensed in the condensing device and recovered into the distillate receiving bottle containing the boric acid absorption liquid;

[0015] When the volume of the liquid in the distillate receiving bottle is 150-180 ml, the liquid in the distillate receiving bottle is titrated with aminosulfonic acid standard titration solution to calculate the nitrogen content in the alloy powder to be tested;

[0016] After the sample test is completed, the distillate receiving bottle is removed, and the water vapor generating device is turned off to discharge the post-reaction liquid in the flask to the waste liquid bottle through the first connecting pipe.

[0017] In an optional embodiment, the volume of water in the water vapor generating device is Mml, the temperature is T°C, the condensing device is a condenser, the lower end of the condenser extends into the liquid in the distillate receiving bottle to an initial depth of Lcm, and L, M, and T satisfy Formula I:

[0018] L=(M / 2000+(M-2000) / 2000)+(T / 390+(T-390) / 390) Formula I.

[0019] In an optional embodiment, the M is 2000-3000, and the T is 390-420.

[0020] The present invention has the following beneficial effects:

[0021] The present application adopts a flask with a special structure as a reaction device. During the sample detection process, the waste liquid can be automatically sucked into the waste liquid bottle, and the subsequent nitrogen content of the sample can be detected without frequent disassembly and assembly of the device.

[0022] The distillation separation nitrogen measurement device and method of the present application are beneficial to improving the test efficiency, reducing the distillation time, and reducing the test error. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0024] Figure 1 Schematic diagram of the structure of a flask for distillation separation and nitrogen measurement;

[0025] Figure 2 This is a schematic diagram of the structure of the distillation separation and nitrogen measurement device.

[0026] Illustration: 100 - flask; 110 - opening; 120 - catheter; 130 - first connecting pipe; 140 - expansion part; 150 - second connecting pipe; 200 - water vapor generating device; 300 - waste liquid bottle; 400 - nitrogen determination ball; 500 - condensing device; 600 - distillate receiving bottle. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0028] The embodiment of the present invention provides a flask 100 for distillation separation and nitrogen measurement, such as Figure 1 As shown, it includes a flask body, wherein a conduit 120, a first connecting tube 130 and a diameter expansion portion 140 are arranged at the bottleneck, the top of the conduit 120 has the same diameter as the bottleneck, and the bottom is located at the bottom of the flask 100; the connection port between the first connecting tube 130 and the bottleneck is located above the conduit 120, the diameter expansion portion 140 is located below the top of the conduit 120, and the diameter expansion portion 140 is further provided with a second connecting tube 150 capable of communicating with the outside of the flask 100 body.

[0029] The flask 100 used for distillation separation and nitrogen measurement in the embodiment of the present application is provided with an opening 110 at the top of the bottleneck to facilitate the addition of liquid into the flask 100. When nitrogen measurement is required, the reaction liquid can be added into the flask 100 from the opening 110, and then water vapor is introduced into the bottom of the flask 100 from the first connecting tube 130 and the conduit 120 to heat the reaction liquid so that the reactants react fully, and the nitrogen-containing gas released after the reaction leaves from the second connecting tube 150; when the reaction is completed, the introduction of water vapor is stopped, and the liquid in the body of the flask 100 will be sucked out along the conduit 120 and the first connecting tube 130. In this way, during the test process, there is no need to remove the flask 100 from the reaction device to pour out the post-reaction liquid, and the waste liquid can be directly extracted, which is more conducive to improving the test efficiency.

[0030] It should be noted that, since the reaction in the flask 100 is relatively violent during the nitrogen measurement process, in order to prevent the reaction liquid from overflowing from the second connecting tube 150, an expansion portion 140 is further provided at the outlet of the second connecting tube 150 to play a buffering role.

[0031] The present application adopts a flask 100 of a special structure as a reaction device. During the sample detection process, the waste liquid can be automatically sucked back into the waste liquid bottle 300, and the subsequent nitrogen content of the sample can be detected without frequent disassembly and assembly of the device.

[0032] The embodiment of the present invention further provides a distillation separation nitrogen measuring device, such as Figure 2 As shown, it includes: a water vapor generating device 200, a waste liquid bottle 300, the flask 100 described in the above embodiment, a nitrogen determination ball 400, a condensing device 500 and a distillate receiving bottle 600 which are sequentially connected by pipelines.

[0033] In some embodiments, the water vapor generating device 200 includes a three-necked flask 100, the mouths of which are all provided with sealing plugs, the liquid adding port is in a normally closed state, and the safety port is provided with a safety tube that can conduct airflow inside and outside the bottle body. The outer end of the safety tube is connected to a rubber safety conduit 120, the air outlet is provided with an air outlet pipe, which is connected to the reaction device, and the connection part is provided with a spiral clamp for controlling the airflow. The flask 100 is connected to the water vapor generating device 200 through a waste liquid bottle 300 for chemical reaction. The condensing device 500 is used to cool the steam generated by the reaction to prevent it from volatilizing. The distillate receiving bottle 600 is used to collect the distilled liquid.

[0034] During the nitrogen measurement process, the water vapor generated by the water vapor generator 200 enters the flask 100 through the waste liquid bottle 300, heats the reaction liquid in the flask 100, and takes out the gas generated by the reaction. The gas passes through the nitrogen ball 400 and the condenser 500 in sequence and is condensed before being collected in the distillate receiving bottle 600. When the distillate receiving bottle 600 has completed collecting the liquid, the distillate receiving bottle 600 is removed, and the outlet valve of the water vapor generator 200 is closed. The reaction liquid in the flask 100 will return to the waste liquid bottle 300 along the conduit 120 and the first connecting pipe 130 due to back suction. When the liquid in the flask 100 has been discharged, the reaction liquid of the subsequent sample can be added to continue the test of the subsequent sample.

[0035] In an optional embodiment, the water vapor generating device 200 includes a container for containing water and a heating device for heating the water in the container.

[0036] When the water vapor generator is heated and boiling at high temperature, the hot air inside the generator cannot be discharged at a uniform speed due to uneven heating, resulting in local concentrated discharge of boiling gas, which may cause boiling gas injuries. The heating device uses an electric heating sleeve, which can be cylindrical with evenly distributed resistance wires inside. It is used for heating, which can balance the air pressure, reduce the occurrence of safety accidents, facilitate the addition of liquid, improve experimental efficiency, increase the heating area of ​​the water vapor generator, and provide sufficient water vapor to speed up the distillation speed.

[0037] The relative position between the units of the device has a significant impact on the distillation rate, vapor path, etc. Improper connection may result in a distillation rate that is difficult to meet the requirement of 120 mL of distilled liquid within 25 minutes, and a nitrogen recovery rate lower than 95%, reducing the accuracy of the test results.

[0038] In an optional embodiment, a water vapor outlet is provided at the top of the water vapor generating device 200, and the horizontal distance between the water vapor outlet and the water vapor inlet of the waste liquid bottle is 19-21 cm, the vertical distance is 5-6 cm, and the pipe diameter is 0.8-1.2 cm.

[0039] The horizontal and vertical distances between the water vapor outlet and the water vapor inlet of the waste liquid bottle will affect the passage time and pressure of the water vapor, and further affect the temperature and volume of the water vapor reaching the flask 100, the heating effect on the reaction liquid and the discharge rate of the nitrogen-containing gas generated by the reaction, and further affect the accuracy of the nitrogen measurement results.

[0040] In an optional embodiment, the horizontal distance between the outlet of the waste liquid bottle and the inlet of the first connecting tube 130 of the flask 100 is 17-19 cm, the vertical distance is 4-5 cm, and the pipe diameter is 0.8-1.2 cm.

[0041] The horizontal and vertical distances between the outlet of the waste liquid bottle and the inlet of the first connecting pipe 130 of the flask 100 will affect the passage time and pressure of the water vapor, and further affect the temperature and volume of the water vapor reaching the flask 100, the heating effect on the reaction liquid and the discharge rate of the nitrogen-containing gas generated by the reaction, and further affect the accuracy of the nitrogen measurement results.

[0042] In an optional embodiment, the horizontal distance between the gas outlet of the flask 100 and the highest point of the nitrogen-fixing ball 400 is 21-23 cm, and the vertical distance is 7-8 cm. The diameter of the pipeline between the flask 100 and the nitrogen-fixing ball 400 is 0.8-1.2 cm.

[0043] The horizontal and vertical distances between the gas outlet of the flask 100 and the highest point of the nitrogen determination ball 400 will affect the passage time and pressure of water vapor, affect the cooling effect of water vapor, and further affect the accuracy of the nitrogen measurement result.

[0044] In an optional embodiment, the nitrogen determining ball 400 is a double-spherical nitrogen determining ball 400, which can better play a buffering role and increase the residence time of the gas, which is beneficial to reducing the temperature of the liquid received in the distillate receiving bottle 600 compared to a single-spherical nitrogen determining ball.

[0045] The embodiment of the present invention further provides a method for measuring nitrogen by distillation separation, comprising:

[0046] The water vapor generating device 200 is started, so that the water vapor passes through the waste liquid bottle, the flask 100 containing the reaction liquid, and the nitrogen ball 400 in sequence, and then is condensed in the condensing device 500 and recovered into the distillate receiving bottle 600 containing the boric acid absorption liquid;

[0047] When the volume of the liquid in the distillate receiving bottle 600 is 150-180 ml, the liquid in the distillate receiving bottle 600 is titrated with aminosulfonic acid standard titration solution to calculate the nitrogen content in the alloy powder to be tested;

[0048] After the sample test is completed, the distillate receiving bottle 600 is removed, and the water vapor generating device 200 is turned off to discharge the post-reaction liquid in the flask 100 to the waste liquid bottle through the first connecting pipe 130 .

[0049] It should be noted that, if necessary, between two sampling tests, water can be added to the flask 100 to clean the flask 100 to avoid high nitrogen content caused by residual reaction liquid; the reaction liquid in the flask 100 is: the sample powder is decomposed in a mixed acid of sulfuric acid and phosphoric acid, and then diluted and an excess of alkali is added to form a reaction liquid: specifically, the sample powder vanadium nitrogen alloy is added to the mixed acid (phosphoric acid ρ = 1.70 g / mL, sulfuric acid ρ = 1.84 g / mL) to dissolve, and then sodium hydroxide solution (500 g / L) is added to obtain the reaction liquid. The method is shown in GB / T 24583.3-2019.

[0050] When adding the reaction liquid to the flask 100 using a funnel (first add the acid solution for dissolving the alloy, then add the sodium hydroxide solution), in order to prevent the reaction liquid from overflowing from the first connecting tube 130, the reaction liquid can be slowly dripped into the flask 100 until the volume of the reaction liquid in the flask 100 is about 1 / 3 of the volume of the flask 100, and then the grinding mask is covered. If necessary, a small amount of water can be added to clean the funnel after adding the reaction liquid.

[0051] Before the distillate receiving bottle 600 is removed, a small amount of distilled water can be used to rinse the lower end of the condensation device 500. Usually, 30 mL of boric acid absorption liquid (20 g / L) and 2d to 3d of methyl red-methylene blue indicator are pre-added to the distillate receiving bottle 600.

[0052] The distillation separation nitrogen measurement device and method of the present application are beneficial to improving the test efficiency, reducing the distillation time, and reducing the test error.

[0053] In an optional embodiment, the volume of water in the water vapor generating device 200 is Mml, the temperature is T°C, the condensing device 500 is a condenser, the lower end of the condenser extends into the liquid in the distillate receiving bottle to an initial depth of Lcm, and L, M, and T satisfy Formula I:

[0054] L=(M / 2000+(M-2000) / 2000)+(T / 390+(T-390) / 390) Formula I.

[0055] In an optional embodiment, the M is 2000-3000, and the T is 390-420.

[0056] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0057] Examples and Comparative Examples

[0058] This embodiment and comparative example provide a method for measuring nitrogen by distillation separation, comprising:

[0059] Device connection, such as Figure 1As shown, a water vapor generator 200, a waste liquid bottle 300 (300 ml), a flask 100 (400 ml), a double-ball nitrogen determination ball 400 and a condenser 500 (snake-shaped condenser, effective length 250 mm) are sequentially connected by a pipeline (inner diameter 1 cm), and a distillate receiving bottle 600 (250 ml conical flask) is arranged at the bottom of the condenser 500; a water vapor outlet is arranged at the top of the water vapor generator 200, and the horizontal distance between the water vapor outlet and the water vapor inlet of the waste liquid bottle is X1 cm, and the vertical distance is Y1 cm; the horizontal distance between the outlet of the waste liquid bottle and the inlet of the first connecting pipe 130 of the flask 100 is X2 cm, and the vertical distance is Y2 cm; the horizontal distance between the gas outlet of the flask 100 and the highest point of the nitrogen determination ball 400 is X3 cm, and the vertical distance is Y3 cm;

[0060] The water vapor generating device 200 is started, so that the water vapor passes through the waste liquid bottle, the flask 100 containing the reaction liquid, and the nitrogen ball 400 in sequence, and then is condensed in the condensing device 500 and recovered into the distillate receiving bottle 600 containing the boric acid absorption liquid;

[0061] When the volume of the liquid in the distillate receiving bottle 600 is 150-180 ml, the liquid in the distillate receiving bottle 600 is titrated with aminosulfonic acid standard titration solution to calculate the nitrogen content in the alloy powder to be tested;

[0062] After the sample test is completed, the distillate receiving bottle 600 is removed and the water vapor generating device 200 is turned off to discharge the reaction liquid in the flask 100 to the waste liquid bottle through the conduit 120 and the first connecting pipe 130, and then perform subsequent sample tests.

[0063] The above method was used to test a vanadium-nitrogen alloy sample (sample number GBW(E)010299) with a nitrogen content of 14.57%. The equipment and step parameters used as well as the test results are shown in Table 1.

[0064] Table 1

[0065]

[0066]

[0067] It can be seen from the above embodiments and comparative examples that in the embodiments of the present application, the distillation time can be shortened to 18 minutes, and the absolute error between the measured value and the standard value can be controlled within ±0.03%, which is much smaller than the comparative example.

[0068] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A flask used for distillation separation and nitrogen measurement, characterized in that: The invention comprises a flask body, wherein the top of the bottleneck of the flask is provided with an opening, and the bottleneck is provided with a conduit, a first connecting tube and a diameter expansion portion, the top of the conduit has the same diameter as the bottleneck, and the bottom is located at the bottom of the flask; the connection port between the first connecting tube and the bottleneck is located above the conduit, the diameter expansion portion is located below the top of the conduit, and the diameter expansion portion is further provided with a second connecting tube capable of communicating with the outside of the flask body.

2. A distillation separation nitrogen measuring device, characterized in that: include: A water vapor generating device, a waste liquid bottle, a flask as claimed in claim 1, a nitrogen determination ball, a condensing device and a distillate receiving bottle are sequentially connected by pipelines.

3. The distillation separation nitrogen measuring device according to claim 2, characterized in that: The water vapor generating device comprises a container for containing water and a heating device for heating the water in the container.

4. The distillation separation nitrogen measuring device according to claim 2, characterized in that: A water vapor outlet is arranged on the top of the water vapor generating device, and the horizontal distance between the water vapor outlet and the water vapor inlet of the waste liquid bottle is 19-21 cm, the vertical distance is 5-6 cm, and the pipeline diameter is 0.8-1.2 cm.

5. The distillation separation nitrogen measuring device according to claim 2, characterized in that: The horizontal distance between the outlet of the waste liquid bottle and the inlet of the first connecting pipe of the flask is 17-19 cm, the vertical distance is 4-5 cm, and the pipe diameter is 0.8-1.2 cm.

6. The distillation separation nitrogen measuring device according to claim 2, characterized in that: The horizontal distance between the gas outlet of the flask and the highest point of the nitrogen determination ball is 21-23 cm, and the vertical distance is 7-8 cm. The diameter of the pipeline between the flask and the nitrogen determination ball is 0.8-1.2 cm.

7. The distillation separation nitrogen measuring device according to claim 2, characterized in that: The nitrogen determination ball is a double-ball type nitrogen determination ball.

8. A method for measuring nitrogen using the distillation separation nitrogen measuring device according to any one of claims 2 to 7, characterized in that: include: The water vapor generating device is started, so that the water vapor passes through the waste liquid bottle, the flask containing the reaction liquid, and the nitrogen determination ball in sequence, and then is condensed in the condensing device and recovered into the distillate receiving bottle containing the boric acid absorption liquid; When the volume of the liquid in the distillate receiving bottle is 150-180 ml, the liquid in the distillate receiving bottle is titrated with aminosulfonic acid standard titration solution to calculate the nitrogen content in the alloy powder to be tested; After the sample test is completed, the distillate receiving bottle is removed, and the water vapor generating device is turned off to discharge the post-reaction liquid in the flask to the waste liquid bottle through the first connecting pipe.

9. The method for measuring nitrogen by the distillation separation nitrogen measuring device according to claim 8, characterized in that: The volume of water in the water vapor generating device is Mml, the temperature is T℃, the condensing device is a condenser, the lower end of the condenser extends into the liquid in the distillate receiving bottle to an initial depth of Lcm, and L, M and T satisfy Formula I: L=(M / 2000+(M-2000) / 2000)+(T / 390+(T-390) / 390) Formula I.

10. The method for measuring nitrogen by the distillation separation nitrogen measuring device according to claim 9, characterized in that: The M is 2000-3000, and the T is 390-420.

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