A heating control method for extracting and enriching krypton and xenon gases

Abstract

The present application relates to the field of industrial air separation, and in particular to a heating control method for krypton-xenon gas extraction and enrichment; the method comprises: controlling the liquid level of krypton-xenon cold accumulated liquid to a stable liquid level, and then performing a first heating to obtain a first krypton-xenon mixed liquid; controlling the flow rate to a stable flow rate, and then performing a second heating to an oxygen component evaporation amount of ≥98% to obtain a second krypton-xenon mixed liquid; controlling the temperature to a stable temperature, and then performing a third heating, and performing oxygen content measurement, density measurement and temperature measurement; judging whether the third krypton-xenon mixed liquid is qualified according to the oxygen content, density and temperature; and effectively and accurately controlling the temperature of different process stages through a multi-stage logic control unit, and fully evaporating the oxygen mixed in the krypton-xenon gas, thereby solving the problem of large temperature fluctuations in a secondary krypton-xenon enrichment tower caused by fluctuations in the heating stage.

Description

Technical Field

[0001] The present application relates to the field of industrial air separation, and in particular to a heating and regulating method for extracting and enriching krypton and xenon gases. Background Art

[0002] The main production process of krypton-xenon gas extraction generally includes the following systems: liquid oxygen filter, lean krypton-xenon enrichment tower, krypton-xenon pump, cold box, electric heater, hydrocarbon catalytic furnace, air bath vaporizer, cooler, molecular sieve adsorber purification system, primary krypton-xenon enrichment tower, secondary krypton-xenon enrichment tower, krypton-xenon liquid separation tank and krypton-xenon membrane compressor. In the stage between the primary krypton-xenon enrichment tower and the secondary krypton-xenon enrichment tower, the lean krypton-xenon gas after passing through the purification system is cooled and then enters the primary krypton-xenon enrichment tower for distillation, liquid oxygen is evaporated and initially purified, and the krypton-xenon mixed liquid at the bottom enters the secondary krypton-xenon enrichment tower for distillation, liquid oxygen is evaporated again, and the krypton-xenon mixed liquid is purified again, and finally a krypton-xenon mixed liquid with a purity of about 98% can be obtained.

[0003] However, in the above process, due to the use of multiple evaporations, multiple transportation and multiple heating are carried out in the system. If the heating control is unstable, it will cause large temperature fluctuations in the secondary krypton-xenon enrichment tower, affecting the purity of the product. Therefore, how to stabilize the temperature fluctuations in the secondary krypton-xenon enrichment tower is a technical problem that urgently needs to be solved. Summary of the invention

[0004] The present application provides a heating control method for krypton-xenon gas extraction and enrichment, so as to solve the technical problem of large temperature fluctuation in a secondary krypton-xenon enrichment tower in the prior art.

[0005] In a first aspect, the present application provides a heating and control method for krypton-xenon gas extraction and enrichment, the method being used to heat and control liquid in a secondary krypton-xenon enrichment tower, the method comprising:

[0006] The liquid level of the krypton-xenon cold accumulated liquid entering the secondary krypton-xenon enrichment tower is controlled to a stable liquid level, and then a first heating is performed to obtain a first krypton-xenon mixed liquid;

[0007] Controlling the flow rate of the first krypton-xenon mixed liquid to a stable flow rate, and then performing a second heating until the evaporation amount of the oxygen component of the krypton-xenon liquid is ≥ 98%, thereby obtaining a second krypton-xenon mixed liquid;

[0008] The second krypton-xenon mixed liquid is temperature controlled to a stable temperature, and then subjected to a third heating to obtain a third krypton-xenon mixed liquid;

[0009] Determining the oxygen content, density and temperature of the third krypton-xenon mixed liquid to obtain oxygen content data, density data and temperature data;

[0010] judging whether the third krypton-xenon mixed liquid is qualified according to the oxygen content data, the density data and the temperature data;

[0011] If yes, the third krypton-xenon mixed liquid is bottled to obtain high-purity krypton-xenon gas;

[0012] Wherein, the second heating comprises performing second heating at the stable liquid level and the stable flow rate;

[0013] The third heating includes performing the third heating at the stable liquid level, the stable flow rate, and the stable temperature.

[0014] Optionally, judging whether the third krypton-xenon mixed liquid is qualified according to the oxygen content data, the density data and the temperature data specifically includes:

[0015] According to the oxygen content data and the standard oxygen content, the density data and the standard density, and the temperature data and the standard temperature, judging whether the third krypton-xenon mixed liquid is qualified;

[0016] If the oxygen content data is greater than the standard oxygen content, and / or the density data is not within the standard density range, and / or the temperature data is not within the standard temperature range, the third krypton-xenon mixed liquid is determined to be unqualified;

[0017] If the oxygen content data ≤ the standard oxygen content, the density data is within the standard density range, and the temperature is within the standard temperature range, the third krypton-xenon mixed liquid is determined to be qualified, and the third krypton-xenon mixed liquid is bottled to obtain high-purity krypton-xenon gas.

[0018] Optionally, the standard oxygen content is ≤3%.

[0019] Optionally, the standard density is 2199kg / m 3 ~2201kg / m 3 .

[0020] Optionally, the standard temperature is -132°C to -130°C.

[0021] Optionally, the second heating temperature is -140°C to -135°C.

[0022] Optionally, the method further includes: performing liquid level detection and flow rate detection on the second krypton-xenon mixed liquid respectively to obtain liquid level data and flow rate data of the second krypton-xenon mixed liquid;

[0023] According to the liquid level data and the flow data, determining whether the second krypton-xenon mixed liquid needs to be level-controlled again to a stable liquid level;

[0024] If yes, the liquid level of the second krypton-xenon mixed liquid is controlled to a stable liquid level.

[0025] Optionally, judging whether the second krypton-xenon mixed liquid needs to be level-controlled again to a stable liquid level according to the liquid level data and the flow rate data specifically includes:

[0026] According to the liquid level data and the size of the standard liquid level, and the flow rate data and the size of the stable flow rate, respectively, determining whether the second krypton-xenon mixed liquid needs to be level-controlled again to a stable liquid level;

[0027] If the liquid level data is less than the stable liquid level, and / or the flow rate data is not within the range of the stable flow rate, it is determined that the second krypton-xenon mixed liquid needs to be level-controlled to a stable liquid level;

[0028] If the liquid level data is greater than or equal to the stable liquid level and the flow rate data is within the range of the stable flow rate, it is determined that the second krypton-xenon mixed liquid enters the next step of processing.

[0029] Optionally, the stable liquid level is ≥ 60%.

[0030] Optionally, the stable flow rate is 6m 3 / h~8m 3 / h.

[0031] Optionally, the first heating is terminated when the oxygen component in the krypton-xenon cold liquid begins to evaporate.

[0032] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0033] The embodiment of the present application provides a heating control method for krypton-xenon gas extraction and enrichment. The method first controls the liquid level of the krypton-xenon cold accumulated liquid to be stable, so that the liquid level control logic can be used to perform the first heating with a stable liquid level. The flow rate of the first krypton-xenon mixed liquid is then controlled to be stable, so that the evaporation amount control logic can be used to perform the second heating with a stable liquid level and a stable flow rate, thereby further accelerating the evaporation of oxygen in the krypton-xenon gas and reducing the evaporation of the krypton-xenon gas product. Finally, the temperature control logic is performed on the second krypton-xenon mixed liquid to be stable, and the oxygen content, density and temperature in the third heating process are detected. The qualification degree of the generated third krypton-xenon mixed liquid is judged by the data of oxygen content, density and temperature. The multi-stage control logic unit can be used to effectively and accurately control the temperature of different process stages, and fully evaporate the oxygen mixed in the krypton-xenon gas, thereby solving the problem of large temperature fluctuation in the secondary krypton-xenon enrichment tower caused by fluctuations in the heating stage. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0036] Figure 1 A schematic diagram of a process for a method provided in an embodiment of the present application;

[0037] Figure 2 Detailed flow chart of the method provided in the embodiment of the present application

[0038] Figure 3 A schematic diagram of a flow chart of adding a second krypton-xenon mixed liquid to control the liquid level in the method provided in an embodiment of the present application;

[0039] Figure 4 for Figure 3 continuation of

[0040] Figure 5 A schematic diagram of the application of the method provided in the embodiment of the present application;

[0041] Among them, 1-secondary krypton-xenon enrichment tower, 2-krypton-xenon enrichment tower heater, 3-krypton-xenon liquid separation tank, 4-krypton-xenon membrane compressor, 5-krypton-xenon bottle filling rack;

[0042] LI is the liquid level at the bottom of the secondary krypton-xenon enrichment tower; LIC is the liquid level control logic; FI is the evaporation amount of the oxygen component in the secondary krypton-xenon enrichment tower; FIC is the evaporation amount control logic of the oxygen component; TI is the bottom temperature of the secondary krypton-xenon enrichment tower; TIC is the temperature control logic. DETAILED DESCRIPTION

[0043] The present invention will be described in detail below in conjunction with specific implementations and examples, and the advantages and various effects of the present invention will be more clearly presented. It should be understood by those skilled in the art that these specific implementations and examples are for illustrating the present invention, rather than limiting the present invention.

[0044] Throughout the specification, unless otherwise specifically stated, the terms used herein should be understood as meanings commonly used in the art. Therefore, unless otherwise defined, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art to which the present invention belongs. In the event of a conflict, the present specification takes precedence.

[0045] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0046] The creative thinking of the present application is: the main production process of krypton-xenon gas extraction, the basic process of which is: krypton and xenon in the atmosphere enter the air separation device along with the air, after gas separation, they are concentrated and accumulated into oxygen-rich liquid in the main condenser evaporator of the air separation, and then pass through a liquid oxygen filter to remove nitrous oxide and some heavy hydrocarbons, and then send it to a lean krypton-xenon enrichment tower for distillation and accumulation, and a lean krypton-xenon liquid is obtained at the bottom of the lean krypton-xenon enrichment tower, and then it is compressed by a krypton-xenon pump and sent to a water bath evaporator for gasification, the obtained lean krypton-xenon gas is heated to a high temperature by an electric heater, and then enters a hydrocarbon catalytic furnace to remove hydrocarbons in the lean krypton-xenon gas, and then enters a cooling system to cool and remove free water, and then enters an adsorber to remove water and carbon dioxide, and then passes through ... After being adsorbed by the adsorption system, the lean krypton-xenon gas is cooled and then enters a first-stage krypton-xenon enrichment tower, wherein the heat source for distillation in the first-stage krypton-xenon enrichment tower comes from the electric heater at the bottom of the tower, so that the liquid oxygen is evaporated and initially purified. The krypton-xenon mixed liquid obtained at the bottom of the first-stage krypton-xenon enrichment tower enters a second-stage krypton-xenon enrichment tower again, wherein the heat source for distillation in the second-stage krypton-xenon enrichment tower comes from the electric heater at the bottom of the tower, the liquid oxygen in the mixed liquid is evaporated again, the krypton-xenon mixed liquid is purified again, and finally a krypton-xenon mixed liquid with a purity of about 98% is obtained. Qualified liquid krypton-xenon products are extracted from the bottom of the second-stage krypton-xenon enrichment tower, stored in a krypton-xenon liquid separation tank, vaporized into gas by a water bath vaporizer, and then sent to a krypton-xenon membrane compressor, and filled into a gas cylinder through isothermal compression.

[0047] The technical solution provided by the embodiment of the present invention is to solve the above technical problems, and the overall idea is as follows:

[0048] In one embodiment of the present application, Figure 1 As shown, a heating and regulating method for krypton-xenon gas extraction and enrichment is provided, the method is used to heat and regulate the liquid in the secondary krypton-xenon enrichment tower, the method comprising:

[0049] S1. Controlling the liquid level of the krypton-xenon cold accumulated liquid entering the secondary krypton-xenon enrichment tower to a stable liquid level, and then performing a first heating to obtain a first krypton-xenon mixed liquid;

[0050] S2. Controlling the flow rate of the first krypton-xenon mixed liquid to a stable flow rate, and then performing a second heating until the oxygen component of the krypton-xenon liquid evaporates ≥ 98%, to obtain a second krypton-xenon mixed liquid;

[0051] S3. The temperature of the second krypton-xenon mixed liquid is controlled to a stable temperature, and then a third heating is performed to obtain a third krypton-xenon mixed liquid;

[0052] S4. Determine the oxygen content, density and temperature of the third krypton-xenon mixed liquid to obtain oxygen content data, density data and temperature data;

[0053] S5. Determine whether the third krypton-xenon mixed liquid is qualified according to the oxygen content data, the density data and the temperature data;

[0054] If yes, the third krypton-xenon mixed liquid is bottled to obtain high-purity krypton-xenon gas;

[0055] Wherein, the liquid level control logic includes first heating at a stable liquid level,

[0056] The evaporation amount control logic includes performing a second heating at the stable liquid level and stable flow rate;

[0057] The temperature control logic includes performing the third heating at the stable liquid level, the stable flow rate and the stable heating temperature.

[0058] In some optional embodiments, such as Figure 2 As shown, judging whether the third krypton-xenon mixed liquid is qualified according to the oxygen content data, the density data and the temperature data specifically includes:

[0059] S501. Determine whether the third krypton-xenon mixed liquid is qualified according to the oxygen content data and the standard oxygen content, the density data and the standard density, and the temperature data and the standard temperature;

[0060] If the oxygen content data is greater than the standard oxygen content, and / or the density data is not within the standard density range, and / or the temperature data is not within the standard temperature range, the third krypton-xenon mixed liquid is determined to be unqualified;

[0061] If the oxygen content data ≤ the standard oxygen content, the density data is within the standard density range, and the temperature is within the standard temperature range, the third krypton-xenon mixed liquid is determined to be qualified, and the third krypton-xenon mixed liquid is bottled to obtain high-purity krypton-xenon gas.

[0062] In the embodiment of the present application, by comprehensively judging the data of oxygen content, density and temperature and standard data, it can be ensured that the purity of the krypton-xenon product in the third krypton-xenon mixed liquid is above 99%.

[0063] In some optional embodiments, the standard oxygen content is ≤3%.

[0064] In the embodiment of the present application, the positive effect of the standard oxygen content ≤ 3% is to ensure that the quality of the krypton-xenon product meets the standard.

[0065] In some optional embodiments, the standard density is 2199 kg / m 3 ~2201kg / m 3 .

[0066] In the present application, the standard density is 2199 kg / m 3 ~2201kg / m 3 The positive effect is to ensure that the purity of krypton-xenon products is qualified; when the standard density is greater than or less than the endpoint value of this range, the adverse effect will be that the purity of krypton-xenon products is unqualified.

[0067] In some optional embodiments, the standard temperature is -132°C to -130°C, and the second heating temperature is -136°C to -135°C.

[0068] In the embodiment of the present application, the positive effect of the standard temperature of -132°C to -130°C is to ensure that the quality and output of krypton-xenon products meet the standards; when the standard temperature is greater than the endpoint value of the range, the adverse effect that will result is a reduction in the output of krypton-xenon products; when the standard temperature is less than the endpoint value of the range, the adverse effect that will result is that the quality of the krypton-xenon products does not meet the standards.

[0069] In some optional embodiments, the second heating temperature is -140°C to -135°C.

[0070] In the embodiment of the present application, the positive effect of controlling the second heating temperature to -140°C to -135°C is that the distillation condition of the krypton-xenon tower can be stabilized; when the second heating temperature is greater than or less than the endpoint value of the range, the adverse effect will be unstable operation of the krypton-xenon tower and disordered distillation condition.

[0071] In some optional embodiments, such as Figure 3 and Figure 4 As shown, the method also includes:

[0072] S21. Performing level detection and flow detection on the second krypton-xenon mixed liquid to obtain level data and flow data of the second krypton-xenon mixed liquid;

[0073] S22. According to the liquid level data and the flow data, determining whether the second krypton-xenon mixed liquid needs to be level-controlled again to a stable liquid level;

[0074] If yes, the liquid level of the second krypton-xenon mixed liquid is controlled to a stable liquid level.

[0075] In the embodiment of the present application, the liquid level and flow rate of the second krypton-xenon mixed liquid are judged to ensure the stability of the liquid level and flow rate. Because the second krypton-xenon mixed liquid is in the heating stage, the flow rate can effectively control the evaporation amount of the oxygen component in the krypton-xenon mixed liquid. Therefore, by judging the liquid level and flow rate of the second krypton-xenon mixed liquid, the liquid level and flow rate of the second krypton-xenon mixed liquid can be controlled to ensure the effective implementation of the third heating, and avoid the temperature change of the third heating due to the fluctuation of the liquid level and flow rate, thereby affecting the purity of the krypton-xenon product.

[0076] In some optional implementations, judging whether the second krypton-xenon mixed liquid needs to be level-controlled again to a stable liquid level according to the liquid level data and the flow rate data specifically includes:

[0077] S221. Determine whether the second krypton-xenon mixed liquid needs to be level-controlled again to a stable liquid level according to the liquid level data and the size of the standard liquid level, the flow data and the size of the stable flow rate;

[0078] If the liquid level data is less than the stable liquid level, and / or the flow rate data is not within the range of the stable flow rate, it is determined that the second krypton-xenon mixed liquid needs to be level-controlled to a stable liquid level;

[0079] If the liquid level data is greater than or equal to the stable liquid level and the flow rate data is within the range of the stable flow rate, it is determined that the second krypton-xenon mixed liquid enters the next step of processing.

[0080] In the embodiment of the present application, by judging the specific liquid level data and flow data, it can be accurately judged whether the second krypton-xenon mixed liquid meets the requirements, thereby ensuring the stability of the liquid level and flow during the third heating process, thereby ensuring the purity of the final krypton-xenon product, and at the same time ensuring the stability of the third heating.

[0081] In some optional embodiments, the stable liquid level is ≥ 60%; and / or,

[0082] The stable flow rate is 6m 3 / h~8m 3 / h.

[0083] In the embodiment of the present application, the positive effect of the stable liquid level ≥ 60% is to ensure that the bottom heater of the krypton-xenon tower is in a fully immersed state and to establish a stable distillation condition; when the stable liquid level is less than the endpoint value of this range, the adverse effect that will result is that the bottom heater of the krypton-xenon tower is at risk of dry burning and damage.

[0084] Stable flow rate is 6m 3 / h~8m 3 / h has the positive effect of ensuring the gas-liquid equilibrium state of the krypton-xenon components; when the value of the stable flow rate is greater than the endpoint value of this range, the adverse effect that will result is the loss of the krypton-xenon product components; when the value of the stable flow rate is less than the endpoint value of this range, the adverse effect that will result is excessive accumulation of impurities in the krypton-xenon product components, thereby reducing the distillation efficiency.

[0085] In some optional embodiments, the first heating is terminated when the oxygen component in the krypton-xenon cold liquid begins to evaporate.

[0086] In the embodiment of the present application, limiting the termination time of the first heating can effectively ensure accurate control of the liquid level in the first heating stage, facilitate the liquid level control logic, and facilitate the subsequent evaporation control logic, thereby ensuring precise control of the temperature of the two heating stages.

[0087] Example 1

[0088] A heating and regulating method for extracting and enriching krypton-xenon gas, used for heating and regulating liquid in a secondary krypton-xenon enrichment tower, comprising:

[0089] S1. The krypton-xenon cold accumulated liquid entering the secondary krypton-xenon enrichment tower is level controlled to be stable, and then the first heating is performed using the level control logic to allow the krypton-xenon liquid to enter the enrichment stage to obtain a first krypton-xenon mixed liquid;

[0090] S2. The flow rate of the first krypton-xenon mixed liquid is controlled to be stable, and then a second heating is performed using an evaporation control logic to stabilize the evaporation amount of the oxygen component of the krypton-xenon liquid to obtain a second krypton-xenon mixed liquid;

[0091] S21. Performing level detection and flow detection on the second krypton-xenon mixed liquid to obtain level data and flow data of the second krypton-xenon mixed liquid;

[0092] S221. Determine whether the second krypton-xenon mixed liquid needs to be level controlled again to a stable level based on the liquid level data and the size of the standard liquid level, the flow data and the size of the stable flow rate;

[0093] If the liquid level data is less than the stable liquid level, and / or the flow data is not within the range of the stable flow, it is determined that the second krypton-xenon mixed liquid needs to be level controlled to a stable liquid level;

[0094] If the liquid level data is greater than or equal to the stable liquid level and the flow rate data is within the range of the stable flow rate, it is determined that the second krypton-xenon mixed liquid enters the next step of processing;

[0095] S3. The temperature of the second krypton-xenon mixed liquid is controlled to a stable temperature, and then a third heating is performed to obtain a third krypton-xenon mixed liquid;

[0096] S4. Determine the oxygen content, density and temperature of the third krypton-xenon mixed liquid to obtain oxygen content data, density data and temperature data;

[0097] S501. Determine whether the third krypton-xenon mixed liquid is qualified based on the oxygen content data and the standard oxygen content, density data and the standard density, temperature data and the standard temperature;

[0098] If the oxygen content data is greater than the standard oxygen content, and / or the density data is not within the standard density range, and / or the temperature data is not within the standard temperature range, the third krypton-xenon mixed liquid is determined to be unqualified;

[0099] If the oxygen content data is less than or equal to the standard oxygen content, the density data is within the standard density range, and the temperature is within the standard temperature range, the third krypton-xenon mixed liquid is determined to be qualified, and the third krypton-xenon mixed liquid is bottled to obtain high-purity krypton-xenon gas;

[0100] Wherein, the second heating includes performing the second heating at a stable liquid level and a stable flow rate;

[0101] The third heating includes performing the third heating at a stable liquid level, a stable flow rate, and a stable temperature.

[0102] Specific control logic units such as Figure 4 shown.

[0103] Standard oxygen content ≤3%.

[0104] Standard density is 2200kg / m 3 .

[0105] The standard temperature is -131°C and the second heating temperature is -136°C.

[0106] Stable liquid level ≥60%.

[0107] Stable flow rate is 7m 3 / h.

[0108] The first heating is terminated when the oxygen component in the krypton-xenon cold accumulation liquid begins to evaporate.

[0109] Example 2

[0110] Comparing Example 2 with Example 1, the difference between Example 2 and Example 1 is:

[0111] Standard density is 2199kg / m 3 .

[0112] The standard temperature is -132°C and the second heating temperature is -136°C.

[0113] Stable flow rate is 6m 3 / h.

[0114] Example 3

[0115] Comparing Example 3 with Example 1, the difference between Example 3 and Example 1 is:

[0116] Standard density is 2201kg / m 3 .

[0117] The standard temperature is -130°C and the second heating temperature is -135°C.

[0118] Stable flow rate is 8m 3 / h.

[0119] Comparative Example 1

[0120] Comparing Comparative Example 1 with Example 1, the difference between Comparative Example 1 and Example 1 is:

[0121] No multi-level logic control unit is used, and the process is carried out directly according to the traditional process.

[0122] Comparative Example 2

[0123] Comparing Comparative Example 2 with Example 1, the difference between Comparative Example 2 and Example 1 is:

[0124] Standard density is 2190kg / m 3 .

[0125] The standard temperature is -135°C and the second heating temperature is -140°C.

[0126] Stable liquid level <60%.

[0127] Stable flow rate is 5m 3 / h.

[0128] Comparative Example 3

[0129] Comparing Comparative Example 3 with Example 1, the difference between Comparative Example 3 and Example 1 is:

[0130] Standard oxygen content>3%.

[0131] Standard density is 2205kg / m 3 .

[0132] The standard temperature is -125°C and the second heating temperature is -140°C.

[0133] Stable flow rate is 10m 3 / h.

[0134] Related experiments:

[0135] The purity of the krypton-xenon products obtained in each embodiment and comparative example was tested, and the results are shown in Table 1.

[0136] Test methods for related experiments:

[0137] Purity of Krypton-Xenon Products:

[0138] In the first heating stage, the reference standard is a two-stage krypton-xenon tower with a standard density of 1200kg / m 3 , stable liquid level ≥60%.

[0139] In the second heating stage, the reference standard is the standard density of the two-stage krypton-xenon tower, which is 1600kg / m 3 , stable liquid level ≥ 60%, stable evaporation flow rate is 6m 3 / h~8m 3 / h.

[0140] The third heating stage uses temperature control, and the temperature is set at -132°C. The reference standard is the standard density of the secondary krypton-xenon tower, which is 2200kg / m 3 , stable liquid level ≥ 60%, standard oxygen content < 3%, at this time the krypton-xenon purity ≥ 98%.

[0141] By adopting the method of the present application, the liquid level of the krypton-xenon cold accumulated liquid is first controlled to be stable, and then the first heating is performed using the liquid level control logic, and then the flow rate of the first krypton-xenon mixed liquid is controlled to be stable, and then the second heating is performed using the evaporation control logic, and finally the temperature of the second krypton-xenon mixed liquid is controlled by the temperature control logic until the temperature is stable, and then the qualification of the generated third krypton-xenon mixed liquid is judged by the data of oxygen content, density and temperature, so that the temperature of different process stages can be effectively and accurately controlled by using a multi-stage control logic unit, so as to solve the problem of large temperature fluctuation in the secondary krypton-xenon enrichment tower caused by fluctuation in the heating stage, and the purity of the final krypton-xenon product can be improved.

[0142] From the data of Comparative Examples 1-3, it can be seen that:

[0143] If the method of the present application is not adopted, or the process parameter range defined in the present application is not adopted, the purity of the obtained krypton-xenon product is low.

[0144] One or more technical solutions in the embodiments of the present application also have at least the following technical effects or advantages:

[0145] (1) The method provided in the embodiment of the present application controls the liquid level of the krypton-xenon cold accumulated liquid, and uses the liquid level control logic to perform the first heating with a stable liquid level, then controls the flow rate of the first krypton-xenon mixed liquid, and uses the evaporation control logic to perform the second heating with a stable liquid level and a stable flow rate, and finally performs the temperature control logic on the second krypton-xenon mixed liquid until the temperature is stable, and finally determines the qualification of the third krypton-xenon mixed liquid generated by combining the data of oxygen content, density and temperature, thereby realizing the use of a multi-stage control logic unit to accurately control the temperature of different process stages, and fully evaporate the oxygen mixed in the krypton-xenon gas, thereby solving the problem of large temperature fluctuations in the secondary krypton-xenon enrichment tower caused by fluctuations in the heating stage, and can improve the purity of the final krypton-xenon product.

[0146] (2) The method provided in the embodiment of the present application is simple to operate because it adopts a control method of a multi-level logic control unit for the secondary krypton-xenon enrichment tower. It can accelerate the finished product conversion rate of the secondary krypton-xenon enrichment tower when the krypton-xenon gas extraction system is initially put into use, and can effectively optimize the process operation of the krypton-xenon gas extraction system and put the krypton-xenon gas extraction system into production and operation more quickly.

[0147] (3) Although the method provided in the embodiment of the present application only improves the heating control of the secondary krypton-xenon enrichment tower, due to the use of a multi-level logic control unit, it can facilitate the adjustment of production operations under any conditions, ensuring the continuity of the entire krypton-xenon gas extraction process, thereby better meeting the demand for krypton-xenon gas products.

[0148] (4) The method provided in the embodiment of the present application adopts control logic as a whole, which can avoid frequent manual operations and reduce the energy of operators, thereby ensuring that the temperature fluctuation in the secondary krypton-xenon enrichment tower is small, the overall operating conditions are stable, and the waste of krypton-xenon raw material products is avoided.

[0149] It should be noted that, in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "include..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0150] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0151] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A heating control method for extracting and enriching krypton and xenon gases, characterized in that: The method is used to heat and regulate the liquid in the secondary krypton-xenon enrichment tower, and the method comprises: The liquid level of the krypton-xenon cold accumulated liquid entering the secondary krypton-xenon enrichment tower is controlled to a stable liquid level, and then a first heating is performed to obtain a first krypton-xenon mixed liquid; Controlling the flow rate of the first krypton-xenon mixed liquid to a stable flow rate, and then performing a second heating until the evaporation amount of the oxygen component of the krypton-xenon liquid is ≥ 98%, thereby obtaining a second krypton-xenon mixed liquid; The second krypton-xenon mixed liquid is temperature controlled to a stable temperature, and then subjected to a third heating to obtain a third krypton-xenon mixed liquid; Determining the oxygen content, density and temperature of the third krypton-xenon mixed liquid to obtain oxygen content data, density data and temperature data; judging whether the third krypton-xenon mixed liquid is qualified according to the oxygen content data, the density data and the temperature data; If yes, the third krypton-xenon mixed liquid is bottled to obtain high-purity krypton-xenon gas; Wherein, the second heating comprises performing second heating at the stable liquid level and the stable flow rate; The third heating comprises performing the third heating at the stable liquid level, the stable flow rate and the stable temperature; The determining whether the third krypton-xenon mixed liquid is qualified according to the oxygen content data, the density data and the temperature data specifically includes: According to the oxygen content data and the standard oxygen content, the density data and the standard density, and the temperature data and the standard temperature, respectively, judging whether the third krypton-xenon mixed liquid is qualified; If the oxygen content data is greater than the standard oxygen content, and / or the density data is not within the standard density range, and / or the temperature data is not within the standard temperature range, the third krypton-xenon mixed liquid is determined to be unqualified; If the oxygen content data is less than or equal to the standard oxygen content, the density data is within the standard density range, and the temperature is within the standard temperature range, the third krypton-xenon mixed liquid is determined to be qualified, and the third krypton-xenon mixed liquid is bottled to obtain high-purity krypton-xenon gas; The standard oxygen content is ≤3%; the standard density is 2199kg / m 3 ~2201kg / m 3 ; The standard temperature is -132℃~-130℃; The second heating temperature is -140℃~-135℃, The stable liquid level is ≥60%; The stable flow rate is 6m 3 / h~8m 3 / h, the third heating temperature is -132°C; The method further comprises: performing liquid level detection and flow rate detection on the second krypton-xenon mixed liquid respectively to obtain liquid level data and flow rate data of the second krypton-xenon mixed liquid; According to the liquid level data and the flow data, determining whether the second krypton-xenon mixed liquid needs to be level-controlled again to a stable liquid level; If yes, the liquid level of the second krypton-xenon mixed liquid is controlled to a stable liquid level.

2. The method according to claim 1, characterized in that The determining, based on the liquid level data and the flow rate data, whether the second krypton-xenon mixed liquid needs to be level-controlled again to a stable liquid level specifically includes: According to the liquid level data and the size of the standard liquid level, and the flow rate data and the size of the stable flow rate, respectively, determining whether the second krypton-xenon mixed liquid needs to be level-controlled again to a stable liquid level; If the liquid level data is less than the stable liquid level, and / or the flow rate data is not within the range of the stable flow rate, it is determined that the second krypton-xenon mixed liquid needs to be level-controlled to a stable liquid level; If the liquid level data is greater than or equal to the stable liquid level and the flow rate data is within the range of the stable flow rate, it is determined that the second krypton-xenon mixed liquid enters the next step of processing.

3. The method according to claim 1, characterized in that The first heating is terminated when the oxygen component in the krypton-xenon cold accumulation liquid begins to evaporate.

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