Automatic control method, system, control device and storage medium for hydrochloric acid production

Abstract

The embodiment of the present application provides an automatic control method, system, control device and storage medium for hydrochloric acid production, which relates to the field of industrial control technology. The control device determines the first fitting concentration value of the hydrogen chloride solution in the first acid tank according to the first liquid level value of the first acid tank; determines whether the concentration of the hydrogen chloride solution in the first acid tank is within a preset normal range according to the first concentration difference between the first fitting concentration value and the first actual concentration value of the hydrogen chloride solution in the first acid tank; if so, adjust the water inlet regulating valve of each absorber according to the actual solution temperature value of each falling film absorber, the second liquid level value of the first acid tank and the second actual concentration value of the hydrogen chloride solution in the first acid tank. The temperature in each falling film absorber is controlled, and the liquid level and concentration of the hydrogen chloride solution in the first acid tank can be synchronously increased, thereby improving the stability of the temperature in the falling film absorber and improving the efficiency of hydrochloric acid production.

Description

Technical Field

[0001] The present application relates to the field of industrial control technology, and in particular to an automatic control method, system, control device and storage medium for hydrochloric acid production. Background Art

[0002] As an important raw material for chemical production, hydrogen chloride is widely used in chemical production. When hydrogen chloride is used in industry to prepare hydrochloric acid, the characteristic of hydrogen chloride gas absorbing water to generate hydrochloric acid is usually used. The continuous absorption of hydrogen chloride gas is achieved through the flow of water in the falling film absorber and the circulation tank to prepare hydrochloric acid with a qualified concentration. Since the concentration of acid in the falling film absorber increases with time, the absorption temperature in the falling film absorber changes continuously, and the water inlet needs to be frequently adjusted adaptively to avoid overheating or overflow of hydrogen chloride gas.

[0003] In the prior art, a hydrochloric acid storage tank circulation system is generally set up to temporarily store the hydrogen chloride solution that does not meet the concentration requirements in the falling film absorber in the hydrochloric acid tank, and the hydrogen chloride solution that does not reach the qualified concentration is continuously pumped to the falling film absorber by a circulation pump until the hydrochloric acid concentration reaches the qualified level before extraction. In the above process, the pressure of the hydrogen chloride gas in each device must also be considered to avoid safety accidents.

[0004] However, the prior art only considers whether the hydrogen chloride gas pressure and hydrochloric acid concentration in each device are qualified, and does not consider other necessary control factors such as water flow and water temperature in the hydrochloric acid production process. In addition, the control of water flow, water temperature and other factors in the prior art must be adjusted manually, and it is impossible to achieve automatic control of the hydrochloric acid production process. Summary of the invention

[0005] The purpose of the present application includes, for example, providing an automatic control method, system, control device and storage medium for hydrochloric acid production, which can adjust the absorber water inlet regulating valve according to the actual concentration value of the hydrogen chloride solution in the acid tank and the second liquid level value to achieve accurate regulation of the concentration of the hydrogen chloride solution in the acid tank. It can also adjust the water inlet according to the temperature of the falling film absorber to achieve the effect of reasonably and accurately controlling the temperature of the falling film absorber.

[0006] The embodiments of the present application can be implemented as follows:

[0007] In a first aspect, the present application provides an automatic control method for hydrochloric acid production, the method comprising:

[0008] Determine a first fitted concentration value of the hydrogen chloride solution in the first acid tank according to a first liquid level value of the first acid tank sent by a first liquid level detection device corresponding to the first acid tank, wherein the first acid tank is an acid tank currently used among the plurality of acid tanks;

[0009] determining whether the concentration of the hydrogen chloride solution in the first acid tank is within a preset normal range according to a first concentration difference between the first fitted concentration value and a first actual concentration value of the hydrogen chloride solution in the first acid tank sent by a first concentration detection device corresponding to the first acid tank;

[0010] If yes, adjusting the water inlet regulating valve of each absorber according to the actual solution temperature value of each falling film absorber sent by each absorber temperature detection device, the second liquid level value of the first acid tank sent by the first liquid level detection device, and the second actual concentration value of the hydrogen chloride solution in the first acid tank sent by the first concentration detection device;

[0011] When the second actual concentration value is equal to the target concentration value, the second acid tank currently in standby is switched to the acid tank currently in use.

[0012] In an optional embodiment, determining a first fitted concentration value of the hydrogen chloride solution in the first acid tank according to a first liquid level value of the first acid tank sent by a first liquid level detection device corresponding to the first acid tank includes:

[0013] According to the pre-obtained liquid level acid concentration fitting curve, a first fitting concentration value corresponding to the first liquid level value in the liquid level acid concentration fitting curve is determined, and the liquid level acid concentration fitting curve is obtained by fitting according to the corresponding concentration values ​​of multiple groups of hydrogen chloride solutions of target concentrations at different liquid level values.

[0014] In an optional embodiment, the step of adjusting the water inlet regulating valve of each absorber according to the actual solution temperature value of each falling film absorber sent by each absorber temperature detection device, the second liquid level value of the first acid tank sent by the first liquid level detection device, and the second actual concentration value of the hydrogen chloride solution in the first acid tank sent by the concentration detection device comprises:

[0015] According to the temperature difference between the actual solution temperature value and the target solution temperature value, the water inlet regulating valve of each absorber is adjusted respectively so that the actual solution temperature value of each falling film absorber meets the preset condition;

[0016] According to the second liquid level value, the second actual concentration value and the actual solution temperature values, the water inlet regulating valves of the absorbers are adjusted respectively so that the concentration of the hydrogen chloride solution in the first acid tank reaches the target concentration value.

[0017] In an optional implementation, the adjusting of each absorber water inlet regulating valve according to the temperature difference between each actual solution temperature value and the target solution temperature value comprises:

[0018] Determining whether a temperature difference between an actual solution temperature value of the first falling film absorber and the target solution temperature value is greater than a preset temperature threshold;

[0019] If the temperature difference is greater than a preset temperature threshold, increasing the valve position of the first absorber water inlet regulating valve;

[0020] At preset time intervals, the above steps are performed until the temperature difference is less than the preset temperature threshold, and the valve position of the first absorber water inlet regulating valve is stopped;

[0021] The first falling film absorber is any one of the plurality of falling film absorbers, and the first absorber water inlet regulating valve is an absorber water inlet regulating valve corresponding to the first falling film absorber.

[0022] In an optional implementation, the adjusting the water inlet regulating valve of each absorber according to the second liquid level value, the second actual concentration value and each actual solution temperature value respectively includes:

[0023] Determine a second fitting concentration value of the first acid tank according to the second liquid level value;

[0024] If a second concentration difference between the second fitted concentration value and the second actual concentration value is greater than a first preset concentration threshold, reducing the valve position of the absorber water inlet regulating valve of the falling film absorber corresponding to the smallest actual solution temperature value among the actual solution temperature values ​​according to the second concentration difference and a preset adjustment coefficient;

[0025] If a third concentration difference between the second actual concentration value and the second fitted concentration value is greater than a first preset concentration threshold, the valve position of the absorber water inlet regulating valve of the falling film absorber corresponding to the largest actual solution temperature value among the actual solution temperature values ​​is increased according to the third concentration difference and the preset adjustment coefficient.

[0026] In an optional embodiment, before determining the first fitting concentration value of the hydrogen chloride solution in the first acid tank according to the first liquid level value of the first acid tank sent by the first liquid level detection device corresponding to the first acid tank, the method further includes:

[0027] The first acid tank is determined according to the states of the acid inlet cut-off valve and the acid outlet cut-off valve of each of the multiple acid tanks.

[0028] In an optional embodiment, switching the currently standby second acid tank to the currently used acid tank comprises:

[0029] Controlling the second acid inlet cut-off valve and the second acid outlet cut-off valve of the second acid tank to open;

[0030] The first acid inlet cut-off valve and the first acid outlet cut-off valve of the first acid tank are controlled to be closed.

[0031] In a second aspect, the present application provides an automatic control device for hydrochloric acid production, the device comprising:

[0032] A determination module is used to determine a first fitting concentration value of the hydrogen chloride solution in the first acid tank according to a first liquid level value of the first acid tank sent by a first liquid level detection device corresponding to the first acid tank, wherein the first acid tank is an acid tank currently used among the multiple acid tanks.

[0033] The determination module is further used to determine whether the concentration of the hydrogen chloride solution in the first acid tank is within a preset normal range according to a first concentration difference between the first fitting concentration value and a first actual concentration value of the hydrogen chloride solution in the first acid tank sent by a first concentration detection device corresponding to the first acid tank.

[0034] The regulating module is used to regulate the water inlet regulating valve of each absorber according to the actual solution temperature value of each falling film absorber sent by the absorber temperature detection device, the second liquid level value of the first acid tank sent by the first liquid level detection device, and the second actual concentration value of the hydrogen chloride solution in the first acid tank sent by the first concentration detection device.

[0035] The slot cutting module is used to switch the currently spare second acid tank to the currently used acid tank when the second actual concentration value is equal to the target concentration value.

[0036] The determination module is also specifically used to determine, based on a pre-obtained liquid level acid concentration fitting curve, a first fitting concentration value corresponding to the first liquid level value in the liquid level acid concentration fitting curve, wherein the liquid level acid concentration fitting curve is fitted based on the corresponding concentration values ​​of multiple groups of hydrogen chloride solutions of target concentrations at different liquid level values.

[0037] The regulating module is further specifically used to regulate the water inlet regulating valves of the absorbers according to the temperature difference between the actual solution temperature values ​​and the target solution temperature value, so that the actual solution temperature value of each falling film absorber meets the preset conditions; and regulate the water inlet regulating valves of the absorbers according to the second liquid level value, the second actual concentration value and the actual solution temperature values, so that the concentration of the hydrogen chloride solution in the first acid tank reaches the target concentration value.

[0038] The regulating module is specifically further used to determine whether the temperature difference between the actual solution temperature value of the first falling film absorber and the target solution temperature value is greater than a preset temperature threshold; if the temperature difference is greater than the preset temperature threshold, the valve position of the first absorber water inlet regulating valve is increased; the above steps are performed at preset time intervals until the temperature difference is less than the preset temperature threshold, and the valve position of the first absorber water inlet regulating valve is stopped; the first falling film absorber is any one of the multiple falling film absorbers, and the first absorber water inlet regulating valve is the absorber water inlet regulating valve corresponding to the first falling film absorber.

[0039] The regulating module is specifically further used to determine a second fitting concentration value of the first acid tank according to the second liquid level value; if a second concentration difference between the second fitting concentration value and the second actual concentration value is greater than a first preset concentration threshold, then according to the second concentration difference and the preset regulation coefficient, the valve position of the absorber water inlet regulating valve of the falling film absorber corresponding to the smallest actual solution temperature value among the actual solution temperature values ​​is reduced; if a third concentration difference between the second actual concentration value and the second fitting concentration value is greater than the first preset concentration threshold, then according to the third concentration difference and the preset regulation coefficient, the valve position of the absorber water inlet regulating valve of the falling film absorber corresponding to the largest actual solution temperature value among the actual solution temperature values ​​is increased.

[0040] The determination module is further specifically configured to determine the first acid tank according to the states of the acid inlet cut-off valve and the acid outlet cut-off valve of each of the multiple acid tanks.

[0041] The grooving module is also specifically used to control the second acid inlet cut-off valve and the second acid outlet cut-off valve of the second acid tank to open; and control the first acid inlet cut-off valve and the first acid outlet cut-off valve of the first acid tank to close.

[0042] In a third aspect, the present application provides an automatic control system for hydrochloric acid production, the system comprising: a control device and a plurality of controlled devices, the plurality of controlled devices comprising: a plurality of falling film absorbers, a plurality of absorber temperature detection devices corresponding one-to-one to the plurality of falling film absorbers, and a plurality of absorber water inlet regulating valves corresponding one-to-one to the plurality of falling film absorbers, a plurality of liquid level detection devices, a plurality of concentration detection devices, a plurality of acid inlet cut-off valves, a plurality of acid outlet cut-off valves, and a plurality of acid tanks, the control device being communicatively connected with each of the controlled devices respectively;

[0043] The control device is used to execute the automatic control method for hydrochloric acid production described in any one of the aforementioned embodiments;

[0044] Each of the falling film absorbers is used to absorb hydrogen chloride gas to obtain a hydrogen chloride solution;

[0045] The multiple absorber water inlet regulating valves are respectively used to adjust the water inlet flow rate of the corresponding falling film absorber;

[0046] The multiple absorber temperature detection devices are respectively used to detect the temperature of the hydrogen chloride solution in the corresponding falling film absorber;

[0047] The plurality of liquid level detection devices correspond one to one with the plurality of acid tanks, and each of the liquid level detection devices is used to detect the liquid level of the hydrogen chloride solution in the corresponding acid tank;

[0048] The multiple concentration detection devices correspond to the multiple acid tanks one by one, and each of the concentration detection devices is used to detect the concentration of the hydrogen chloride solution in the corresponding acid tank;

[0049] Each of the acid inlet cut-off valves and each of the acid outlet cut-off valves are used to control the inlet and outlet of the hydrogen chloride solution in the corresponding acid tank.

[0050] In a fourth aspect, the present application provides a control device, comprising: a processor, a storage medium and a bus, the storage medium storing machine-readable instructions executable by the processor, and when the control device is running, the processor and the storage medium communicate through the bus, and the processor executes the machine-readable instructions to perform the steps of the automatic control method for hydrochloric acid production described in any one of the aforementioned embodiments.

[0051] In a fifth aspect, the present application provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the steps of the automatic control method for hydrochloric acid production described in any one of the aforementioned embodiments are implemented.

[0052] The beneficial effects of the embodiments of the present application include:

[0053] The automatic control method, system, control device and storage medium for hydrochloric acid production provided by the present application are adopted. First, the control device adjusts the water inlet flow rate of each falling film absorber by adjusting the water inlet regulating valve of each absorber to control the temperature of the hydrogen chloride solution in the falling film absorber not to exceed the normal range, thereby improving the temperature stability in the falling film absorber. Secondly, the control device can also adjust the water inlet flow rate of each falling film absorber according to the second liquid level value and the second actual concentration value in the first acid tank, further control the concentration and liquid level of the hydrogen chloride solution in the first acid tank, thereby improving the automation and intelligence of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application 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 paying creative work.

[0055] Figure 1 This is a process flow chart for preparing hydrochloric acid in the prior art;

[0056] Figure 2 A schematic diagram of the structure of each controlled device in the automatic control system for hydrochloric acid production provided in an embodiment of the present application;

[0057] Figure 3 A schematic flow chart of the steps of an automatic control method for hydrochloric acid production executed by a control device in an automatic control system for hydrochloric acid production provided in an embodiment of the present application;

[0058] Figure 4 A schematic flow chart of the steps of the automatic control method for hydrochloric acid production provided in an embodiment of the present application;

[0059] Figure 5 The fitted concentration curve and the actual concentration curve according to time changes in the first acid tank of the automatic control method for hydrochloric acid production provided in the embodiment of the present application;

[0060] Figure 6 A schematic diagram of a liquid level acid concentration fitting curve of the automatic control method for hydrochloric acid production provided in an embodiment of the present application;

[0061] Figure 7 A schematic diagram of another step flow of the automatic control method for hydrochloric acid production provided in an embodiment of the present application;

[0062] Figure 8 A schematic diagram of another step flow of the automatic control method for hydrochloric acid production provided in an embodiment of the present application;

[0063] Fig. 9 This is a curve showing the change of solution temperature over time in the falling film absorber before the control device performs temperature control;

[0064] Fig.10 A curve showing the change of the solution temperature over time in the falling film absorber after the temperature control of the automatic control method for hydrochloric acid production provided in an embodiment of the present application;

[0065] Fig.11 A schematic diagram of another step flow of the automatic control method for hydrochloric acid production provided in an embodiment of the present application;

[0066] Fig.12It is a schematic diagram of the matching relationship between the actual solution temperature curve and the actual liquid level curve in the first acid tank before the control device performs concentration control;

[0067] Fig.13 A schematic diagram of the matching relationship between the actual solution temperature curve and the actual liquid level curve in the first acid tank after concentration control in the automatic control method for hydrochloric acid production provided in an embodiment of the present application;

[0068] Fig.14 A schematic diagram of another step flow of the automatic control method for hydrochloric acid production provided in an embodiment of the present application;

[0069] Fig.15 A schematic diagram of the structure of an automatic control device for hydrochloric acid production provided in an embodiment of the present application;

[0070] Fig.16 A schematic diagram of the structure of a control device provided in an embodiment of the present application.

[0071] Icons: 101-falling film absorption device; 102-hydrochloric acid tank; 2011-first falling film absorber; 2012-second falling film absorber; 2013-third falling film absorber; 2014-fourth falling film absorber; 2021-first absorber temperature detection device; 2022-second absorber temperature detection device; 2023-third absorber temperature detection device; 2024-fourth absorber temperature detection device; 2031-first absorber water inlet regulating valve; 2032-second absorber water inlet regulating valve; 2033-third absorber water inlet regulating valve; 2034-fourth absorber water inlet regulating valve; 2041-first liquid level detection device; 2042-second liquid level detection device; 2051-first concentration detection device; 2052-second concentration detection device; 2061-first acid inlet cut-off valve; 2062-second acid inlet cut-off valve; 2071a-first reflux acid outflow cut-off valve; 2071b-first de-tank acid outflow cut-off valve; 2072a-second reflux acid outflow cut-off valve; 2072b-second de-tank acid outflow cut-off valve; 2081-first acid tank; 2082-second acid tank; 10-automatic control device for hydrochloric acid production; 1001-determination module; 1002-regulation module; 1003-grooving module; 2001-processor; 2002-memory. DETAILED DESCRIPTION

[0072] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0073] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0074] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0075] In addition, the terms “first”, “second”, etc., if used, are merely used to distinguish between the descriptions and should not be understood as indicating or implying relative importance.

[0076] It should be noted that, in the absence of conflict, the features in the embodiments of the present application may be combined with each other.

[0077] Falling film absorption is a common process for preparing hydrochloric acid in industry. Hydrogen chloride gas is absorbed by water stored in the falling film absorber to obtain a hydrogen chloride solution, which is then discharged into the acid tank. As the temperature in the falling film absorber and the hydrogen chloride solution in the acid tank change continuously, it is necessary to adaptively adjust the water inlet of the falling film absorber to obtain a hydrochloric acid solution of qualified concentration while avoiding overheating in the falling film absorber or overflow of hydrogen chloride gas.

[0078] Figure 1 The figure shows a process flow chart of hydrochloric acid preparation in the prior art. Figure 1 As shown, the falling film absorption device 101 absorbs hydrogen chloride gas to obtain a hydrogen chloride solution, which is temporarily stored in the hydrochloric acid tank 102. The concentration detector in the hydrochloric acid tank 102 further detects the concentration of the hydrogen chloride solution. If the concentration is unqualified, the hydrogen chloride solution in the hydrochloric acid tank 102 is continuously pumped to the falling film absorption device 101 through a circulation pump, and the absorption is circulated in this way until the concentration of the hydrogen chloride solution in the hydrochloric acid tank 102 is qualified, and the hydrochloric acid solution is extracted. Figure 1 In the hydrochloric acid preparation process shown, only whether hydrochloric acid with a qualified concentration can be obtained in the end is considered. The system cannot control other necessary control factors in the hydrochloric acid preparation process, such as water flow, water temperature, etc., and further adjustments need to be made manually, resulting in a waste of manpower. Due to the high frequency of temperature changes in the falling film absorption device 101, the absorption rate of hydrogen chloride gas by the falling film absorption device 101 is uncertain, resulting in the difficulty in adjusting the concentration to a qualified range when preparing hydrochloric acid by a circulating pump, and the efficiency is low. In addition, it is also possible that hydrogen chloride gas may overflow due to the failure of the falling film absorption device 101 to absorb it in time, increasing environmental risks.

[0079] To this end, the present application proposes an automatic control method, system, control device and storage medium for hydrochloric acid production, which can adjust the temperature of the falling film absorber and the concentration of the hydrogen chloride solution in the first acid tank by adjusting the absorber water inlet regulating valve, thereby improving the automatic control and intelligent degree of the hydrochloric acid production process and improving the production efficiency of hydrochloric acid. It also improves the stability of the temperature in the falling film absorber, thereby ensuring the timely absorption of hydrogen chloride gas.

[0080] The embodiments of the present application provide an automatic control method, system, control device and storage medium for hydrochloric acid production, which are described in detail below.

[0081] In the process of gasification of organic compounds, a large amount of hydrogen chloride gas is generated. Using it to produce byproduct hydrochloric acid is the main way to prepare hydrochloric acid in chemical production. The system includes: control device and multiple controlled devices, please refer to Figure 2 , Figure 2 The figure shows a schematic diagram of multiple controlled devices in the automatic control system for hydrochloric acid production provided by the embodiment of the present application. The multiple controlled devices include: multiple falling film absorbers, multiple absorber temperature detection devices corresponding to the multiple falling film absorbers, and multiple absorber water inlet regulating valves corresponding to the multiple falling film absorbers, multiple liquid level detection devices, multiple concentration detection devices, multiple acid inlet cut-off valves, multiple acid outlet cut-off valves, and multiple acid tanks, and the control device is respectively connected to each controlled device for communication.

[0082] The control device is used to execute the automatic control method for hydrochloric acid production in the following embodiment.

[0083] Each falling film absorber is used to absorb hydrogen chloride gas to obtain hydrogen chloride solution.

[0084] A plurality of absorber inlet regulating valves are respectively used to adjust the inlet flow rate of the corresponding falling film absorber.

[0085] The multiple absorber temperature detection devices are respectively used to detect the temperature of the hydrogen chloride solution in the corresponding falling film absorber.

[0086] The multiple liquid level detection devices correspond to the multiple acid tanks one by one, and each liquid level detection device is used to detect the liquid level of the hydrogen chloride solution in the corresponding acid tank.

[0087] The multiple concentration detection devices correspond to the multiple acid tanks one by one, and each concentration detection device is used to detect the concentration of the hydrogen chloride solution in the corresponding acid tank.

[0088] Each acid inlet cut-off valve and each acid outlet cut-off valve are used to control the inlet and outlet of the hydrogen chloride solution in the corresponding acid tank.

[0089] Below, according to Figure 2 The structural diagram of each controlled device and Figure 3The control device shown in the figure performs a step flow diagram of the automatic control method for hydrochloric acid production, and takes the automatic control system for hydrochloric acid production including 4 falling film absorbers and 2 acid tanks as an example to illustrate the process flow of hydrochloric acid production by the system. Figure 3 The dashed box represents the input variable of the control device, the solid box represents the processing action performed by the controller, and the dotted box represents the output variable of the control device.

[0090] First, the reaction materials pass through the hydrogen chloride separation tower to separate the hydrogen chloride gas and obtain the organic material. The hydrogen chloride gas is respectively input into the first falling film absorber 2011, the second falling film absorber 2012, the third falling film absorber 2013 and the fourth falling film absorber 2014 for absorption. It should be noted that before the hydrogen chloride gas enters the above-mentioned falling film absorbers, the control device adjusts the first absorber water inlet regulating valve 2031, the second absorber water inlet regulating valve 2032, the third absorber water inlet regulating valve 2033 and the fourth absorber water inlet regulating valve 2034 corresponding to each falling film absorber to allow industrial water to enter each falling film absorber. In addition, when the hydrogen chloride solution in the standby acid tank does not reach the qualified concentration, but the liquid level of the hydrogen chloride solution has exceeded the normal range, it can be used as a circulating acid and pumped into each falling film absorber after being detected by an acidity meter.

[0091] Next, the control device can include: the first reflux out acid cut-off valve 2071a, the first go tank out acid cut-off valve 2071b and the second go tank out acid cut-off valve by the first acid inlet cut-off valve 2061, the second acid inlet cut-off valve 2062 and the first acid out cut-off valve, and can include: the second reflux out acid cut-off valve 2072a, the second go tank out acid cut-off valve 2072b state, determine the acid tank currently used. Exemplarily, when the first acid inlet cut-off valve 2061, the first reflux out acid cut-off valve 2071a, the first go tank out acid cut-off valve 2071b are all open states, the first acid tank 2081 is the acid tank currently used.

[0092] The liquid level of the solution in the first acid tank 2081 is detected by the first liquid level detection device 2041 in the first acid tank 2081, and a first liquid level value is obtained and sent to the control device, and the control device determines the first fitting concentration value corresponding to the first liquid level value according to the liquid level acid concentration fitting curve obtained in advance. Since the concentration of the hydrogen chloride solution in the first acid tank 2081 increases with the increase of its liquid level, the first fitting concentration value is used to express the concentration that should be reached at the first liquid level value when the concentration of the hydrogen chloride solution in the first acid tank 2081 is the target concentration value.

[0093] In addition, the first concentration detection device 2051 in the first acid tank 2081 detects the first actual concentration value of the current hydrogen chloride solution in the first acid tank 2081, and sends it to the control device. The control device compares the first fitted concentration value determined above with the first actual concentration value, and according to the first concentration difference ΔCT, determines whether the concentration of the hydrogen chloride solution in the first acid tank 2081 is within the preset normal interval. If not, the control device performs operating condition one, and acid is poured, and the part of the hydrogen chloride solution in the first acid tank 2081 is transported to the second acid tank 2082 for standby use. Optionally, the above-mentioned acid pouring process can be realized by controlling the first reflux acid cut-off valve 2071a or the first tank acid cut-off valve 2071b and the second reflux acid cut-off valve 2072a or the second tank acid cut-off valve 2072b.

[0094] If yes, the control device performs temperature control and concentration control in sequence. First, the control device adjusts the absorber water inlet regulating valve corresponding to each falling film absorber according to the actual solution temperature value of the hydrogen chloride solution in each falling film absorber sent by the first absorber temperature detection device 2021, the second absorber temperature detection device 2022, the third absorber temperature detection device 2023 and the fourth absorber temperature detection device 2024 in each falling film absorber, so as to control the temperature of the hydrogen chloride solution in each falling film absorber. Exemplarily, when the temperature difference between the actual solution temperature value of the first falling film absorber 2011 and the preset target solution temperature value is greater than the preset temperature threshold, the temperature of the first absorber water inlet regulating valve 2031 is increased, and the water inlet is increased to cool down the hydrogen chloride solution in the first falling film absorber 2011. At every preset time interval, the control device again determines the temperature of the hydrogen chloride solution in the first falling film absorber 2011 according to the received temperature detection devices of each absorber until the temperature difference is less than the preset temperature threshold, and stops adjusting the valve position of the first absorber water inlet regulating valve 2031. It can be understood by those skilled in the art that the above temperature control process can be performed sequentially or synchronously for multiple falling film absorbers in the system, and this application does not limit it here.

[0095] After the temperature control is completed, the control device can sort the actual solution temperature values ​​sent again by each absorber temperature detection device to obtain a temperature sorting result. Further, the second fitting concentration value is determined according to the first liquid level detection device 2041 in the first acid tank 2081, and the difference between the second actual concentration value of the first acid tank 2081 is determined to determine the second concentration difference. Finally, the concentration control is performed according to the above-mentioned temperature sorting result and the concentration threshold. Optionally, when the second concentration difference is greater than the first preset concentration threshold, it means that the second fitting concentration value is greater than the second actual concentration value, then the valve position adjustment amount is determined according to the preset adjustment coefficient and the second concentration difference, and the control device further reduces the valve position of the absorber water inlet regulating valve of the falling film absorber with the lowest actual solution temperature value in the above-mentioned temperature sorting result according to the above-mentioned valve position adjustment amount to ensure that the concentration of the falling film absorber with a higher temperature does not decrease. The control device can also determine the third concentration difference according to the difference between the above-mentioned second actual concentration value and the second fitting concentration value. When the third concentration difference is greater than the first preset concentration threshold, indicating that the second fitted concentration value is less than the second actual concentration value, the valve position adjustment amount is determined according to the preset adjustment coefficient and the third concentration difference. The control device further increases the valve position of the absorber inlet regulating valve of the falling film absorber having the highest actual solution temperature value in the above temperature sorting result according to the above valve position adjustment amount, so as to reduce the concentration of the falling film absorber with the highest temperature.

[0096] It can be understood that the spare second acid tank 2082 can calculate its fitting concentration through the second liquid level detection device 2042, and can also obtain its actual concentration according to the second concentration detection device 2052.

[0097] At last, when the concentration of the hydrogen chloride solution in the first acid tank 2081 was qualified, all valves of the first acid tank 2081 of current use can be closed, comprise the first acid inlet cut-off valve 2061, the first reflux out acid cut-off valve 2071a and the first go jar and go out acid cut-off valve 2071b, all valves of the second acid tank 2082 for standby use are opened simultaneously, comprise the second acid inlet cut-off valve 2062, the second reflux out acid cut-off valve 2072a and the second go jar and go out acid cut-off valve 2072b.Like this, the second acid tank 2082 is switched to the acid tank of current use, and has produced qualified hydrochloric acid in the first acid tank 2081.

[0098] The above scenario description of the controlled device of the automatic control system for hydrochloric acid production is merely an application example. The application scenario of the control device in the automatic control system for hydrochloric acid production described in the embodiment of the present application is only to more clearly illustrate the technical solution of the embodiment of the present application, and does not constitute a limitation on the technical solution provided in the embodiment of the present application.

[0099] In order to clearly explain the automatic control method for hydrochloric acid production performed by the control device in the automatic control system for hydrochloric acid production of the present application, the automatic control method for hydrochloric acid production provided by the present application is explained as follows in combination with application examples of multiple embodiments.

[0100] Figure 4 The figure shows a flow chart of an embodiment of the automatic control method for hydrochloric acid production provided in the embodiment of the present application, and the execution subject of the method is the control device in the above embodiment. Figure 4 As shown, the method includes the following steps.

[0101] S301, determining a first fitting concentration value of a hydrogen chloride solution in the first acid tank according to a first liquid level value of the first acid tank sent by a first liquid level detection device corresponding to the first acid tank.

[0102] Among them, the first acid tank is the acid tank currently used among the multiple acid tanks.

[0103] It is understandable that among the multiple alternative acid tanks, one can be selected as the acid tank currently in use, namely the first acid tank, which is connected to the falling film absorber, and the falling film absorber transports the hydrogen chloride solution to the first acid tank currently in use.

[0104] A first liquid level detection device is provided in the first acid tank, for detecting a first liquid level value of the first acid tank and sending the first liquid level value to the control device. Optionally, the first liquid level detection device can detect the liquid level value of the first acid tank at every preset detection time interval.

[0105] It should be noted that, in the present application embodiment, the concentration of the hydrogen chloride solution in the first acid tank is to slowly increase with the liquid level value of the first acid tank simultaneously, and in the present application embodiment, when the concentration of the hydrogen chloride solution in the first acid tank reaches the target concentration value, the liquid level of the hydrogen chloride solution just arrives at the liquid level upper limit of the first acid tank.Therefore, when the first liquid level value is different, the concentration of the hydrogen chloride solution in its first acid tank is also different.Like this, the control device just can determine the corresponding first fitting concentration value when the hydrogen chloride solution in the first acid tank is the hydrochloric acid of the target concentration value according to the current first liquid level value.

[0106] S302, determining whether the concentration of the hydrogen chloride solution in the first acid tank is within a preset normal range according to a first concentration difference between the first fitted concentration value and a first actual concentration value of the hydrogen chloride solution in the first acid tank sent by a first concentration detection device corresponding to the first acid tank.

[0107] After the control device determines the first fitting concentration value, the first concentration detection device disposed in the first acid tank sends the first actual concentration value of the hydrogen chloride solution in the first acid tank to the control device. Optionally, the preset detection time interval of the first concentration detection device can be the same as that of the first liquid level detection device, so as to perform detection synchronously to ensure that the obtained first actual concentration value and the first fitting concentration value correspond to the same first liquid level value. Figure 5 The figure shows the fitted concentration curve and the actual concentration curve according to time changes in the first acid tank. It can be seen that the first concentration difference ΔCT of the first liquid level value can be determined according to the difference between the first fitted concentration value and the first actual concentration value at the same time.

[0108] The preset normal interval may be an interval in which the first concentration difference ΔCT is within a controllable range. It can be understood that when the first concentration difference is within the preset normal interval, the control device makes a small adjustment to the hydrogen chloride solution in the first acid tank to obtain hydrochloric acid with a target concentration value.

[0109] If the first concentration difference is not within the preset normal range, for example, the first actual concentration value corresponding to the current first liquid level value is much smaller than the first fitting concentration value, so that the first concentration difference ΔCT exceeds the preset normal range, the control device determines that the current condition is operating condition 1, and controls the acid outlet cut-off valve of the first acid tank and the acid inlet cut-off valve of the second acid tank to open, so as to transfer part or all of the hydrogen chloride solution in the first acid tank to the second acid tank.

[0110] S303: If yes, then adjust the water inlet regulating valve of each absorber according to the actual solution temperature value of each falling film absorber sent by each absorber temperature detection device, the second liquid level value of the first acid tank sent by the first liquid level detection device, and the second actual concentration value of the hydrogen chloride solution in the first acid tank sent by the first concentration detection device.

[0111] Since each falling film absorber generates heat when absorbing hydrogen chloride gas, the temperature in the falling film absorber changes with the change of the concentration of the hydrogen chloride solution in the falling film absorber. Therefore, an absorber temperature detection device is provided in each falling film absorber to detect the temperature of the hydrogen chloride solution in each falling film absorber in real time or periodically.

[0112] If the first concentration difference is within the preset normal range, the control device determines that the current state is operating condition 2, and the hydrogen chloride solution in the first acid tank can be further controlled. The first liquid level detection device and the first concentration detection device arranged in the first acid tank can detect the liquid level and concentration of the hydrogen chloride solution in the first acid tank again at preset detection time intervals, obtain a second liquid level value and a second actual concentration value, and send them to the control device.

[0113] In this embodiment, since the flow rate of the hydrogen chloride gas is automatically adjusted by the advanced process control (APC) model predictive controller according to the temperature of the sensitive plate in the hydrogen chloride separation tower and the load change, and the flow rate and the water inlet amount jointly affect the solution temperature in the falling film absorber and the concentration of the hydrogen chloride solution in the first acid tank and the falling film absorber, the water inlet amount of the falling film absorber can be controlled to achieve self-adaptation with the flow rate of the hydrogen chloride gas, thereby achieving the purpose of controlling the temperature in the falling film absorber and the concentration of the hydrogen chloride solution in the first acid tank and each falling film absorber.

[0114] Therefore, the control device can determine the water inlet amount of each falling film absorber according to the actual solution temperature value of each falling film absorber, the second liquid level value and the concentration of the hydrogen chloride solution in the first acid tank and the falling film absorber determined by the second actual concentration value, thereby adjusting the water inlet regulating valve of each absorber to achieve the determined corresponding water inlet amount.

[0115] S304, when the second actual concentration value is equal to the target concentration value, the second acid tank currently in standby mode is switched to the acid tank currently in use.

[0116] The hydrogen chloride solution having a solution concentration value of the target concentration value can be understood as the concentration of the hydrochloric acid to be produced which is preset by the staff. Therefore, when the second actual concentration value of the hydrogen chloride solution in the first acid tank is equal to the target concentration value, the target hydrochloric acid product is obtained, and the hydrochloric acid in the first acid tank can be produced at this time.

[0117] To ensure that the system can still operate normally during the process of extracting hydrochloric acid, the control device can control the spare second acid tank to replace the first acid tank in real time and switch to the acid tank currently in use.

[0118] In this embodiment, the water inlet flow rate of each falling film absorber is adjusted by adjusting the water inlet regulating valve of each absorber to achieve control of the temperature in each falling film absorber, and the liquid level and concentration of the hydrogen chloride solution in the first acid tank can be increased synchronously, thereby improving the temperature stability in the falling film absorber, avoiding the overflow of hydrogen chloride gas, and improving the automation degree of the system, thereby improving the efficiency of hydrochloric acid production and reducing the workload of the staff.

[0119] Optionally, in the above step S301, determining a first fitted concentration value of the hydrogen chloride solution in the first acid tank according to the first liquid level value of the first acid tank sent by the first liquid level detection device corresponding to the first acid tank may include: determining a first fitted concentration value corresponding to the first liquid level value in the liquid level acid concentration fitting curve according to a pre-obtained liquid level acid concentration fitting curve, wherein the liquid level acid concentration fitting curve is obtained by fitting according to the expected concentration values ​​of multiple groups of hydrogen chloride solutions with target concentrations at different liquid level values.

[0120] Optionally, multiple groups of data on the concentration and liquid level of the hydrogen chloride solution in the acid tank may be collected in advance when the hydrochloric acid having a target concentration is produced and the liquid level reaches the upper limit of the liquid level of the acid tank and the concentration of the hydrogen chloride solution in the acid tank reaches the target concentration. Figure 6 As shown in the figure, based on the data obtained after multiple collection and screening, the polynomial method is used to obtain the liquid level acid concentration fitting curve in the hydrochloric acid production of the target concentration value, which is used to express the corresponding relationship between different liquid level values ​​and concentration values ​​in the target hydrochloric acid production. The goodness of fit evaluation of the liquid level acid concentration fitting curve shows that the correlation coefficient R 2 =1, it has feasibility and linear relationship, and the fitting effect is good.

[0121] It is understandable that the above-mentioned target concentration value can be determined by the staff according to production needs, and a plurality of liquid level acid concentration fitting curves corresponding to the target concentration values ​​can be pre-generated and stored in the control device, and the corresponding liquid level acid concentration fitting curve can be directly called when producing hydrochloric acid.

[0122] In this way, the first fitting concentration value corresponding to the liquid level acid concentration fitting curve under the target concentration value can be determined according to the first liquid level value of the first acid tank. Optionally, the second fitting concentration value can be determined according to the second liquid level value in the same way.

[0123] In this embodiment, a liquid level acid concentration curve is obtained by fitting multiple groups of reasonable data, and then the fitting concentration is determined according to the liquid level in the acid tank. In this way, the concentration of hydrochloric acid can be accurately controlled throughout the process of producing hydrochloric acid, avoiding the problem that the acid tank is not full when hydrochloric acid with a target concentration value is obtained or the concentration of the hydrogen chloride solution is still unqualified when the acid tank is full, thereby improving the production efficiency of hydrochloric acid.

[0124] Alternatively, if Figure 7 As shown, in the above step S303, the water inlet regulating valve of each absorber is adjusted according to the actual solution temperature value of each falling film absorber sent by the temperature detection device of each absorber, the second liquid level value of the first acid tank sent by the first liquid level detection device, and the second actual concentration value of the hydrogen chloride solution in the first acid tank sent by the concentration detection device, which may include the following steps S401 to S402.

[0125] S401, adjusting the water inlet regulating valves of the absorbers respectively according to the temperature difference between the actual solution temperature and the target solution temperature, so that the actual solution temperature of each falling film absorber meets the preset condition.

[0126] The target solution temperature value may be the highest temperature value at which each falling film absorber can operate normally, and the temperature difference value may be determined based on the difference between each actual solution temperature value and the target solution temperature value. When the temperature of the hydrogen chloride solution in each falling film absorber gradually increases to exceed the target solution temperature value, the falling film absorber is overheated, resulting in a decrease in its absorption rate of hydrogen chloride gas. When the flow rate of hydrogen chloride gas does not change in a short period of time, the decrease in the absorption rate of the falling film absorber may cause the hydrogen chloride gas to overflow. Therefore, it is necessary to control the solution temperature in each falling film absorber to be lower than the target solution temperature value.

[0127] Therefore, in the embodiment of the present application, when the temperature difference is greater than zero, that is, each actual solution temperature value is greater than the target solution temperature value, the control device can adjust the water inlet to reduce the temperature of the solution in each falling film absorber, so as to realize the temperature control of each falling film absorber by the control device, so that the difference between the actual solution temperature value and the target solution temperature value of each falling film absorber is less than zero, and the preset condition is met. Exemplarily, when the temperature difference of a certain falling film absorber is greater than zero, the valve position of the absorber water inlet regulating valve of the falling film absorber can be adaptively increased to increase the water inlet, thereby reducing the temperature of the hydrogen chloride solution in the falling film absorber.

[0128] S402, adjusting the water inlet regulating valve of each absorber according to the second liquid level value, the second actual concentration value and the actual solution temperature values, so that the concentration of the hydrogen chloride solution in the first acid tank reaches the target concentration value.

[0129] As described in the above embodiment, the second liquid level value and the second actual concentration value can be used to determine the concentration deviation value of the hydrogen chloride solution in the first acid tank at the second liquid level value relative to the process of producing hydrochloric acid with a target concentration value.

[0130] Therefore, after the control device adjusts the actual solution temperature value of each falling film absorber to meet the preset conditions, the control device can further perform concentration control on this basis. Optionally, the control device can determine the required water inlet amount for the concentration of the hydrogen chloride solution in the first acid tank to reach the target concentration value based on the second liquid level value, the second actual concentration value and the actual solution temperature value collected again, and adjust the absorber water inlet regulating valves corresponding to each falling film absorber accordingly, so that the concentration of the hydrogen chloride solution in the first acid tank reaches the target concentration value.

[0131] In this embodiment, the control device performs temperature control and concentration control respectively, and gradually adjusts the target concentration value of the hydrogen chloride solution in the first acid tank while ensuring that each falling film absorber does not overheat, thereby reducing the potential safety hazards in the hydrochloric acid production process and improving the accuracy of the hydrochloric acid concentration control.

[0132] Alternatively, if Figure 8As shown, in the above step S401, the water inlet regulating valve of each absorber is adjusted respectively according to the temperature difference between each actual solution temperature value and the target solution temperature value, which can be achieved by the following steps S501 to S503.

[0133] S501, determining whether a temperature difference between an actual solution temperature value and a target solution temperature value of a first falling film absorber is greater than a preset temperature threshold.

[0134] Exemplarily, the value of the preset temperature threshold may be zero. Thus, from the above description, if the actual solution temperature of the first falling film absorber is greater than the target solution temperature, the temperature difference is greater than the preset threshold and the falling film absorber is over-temperature.

[0135] If the actual solution temperature of the first falling film absorber is lower than the target solution temperature, the temperature difference is lower than the preset threshold value, and the falling film absorber operates within a normal temperature range.

[0136] S502: If the temperature difference is greater than a preset temperature threshold, the valve position of the first absorber water inlet regulating valve is increased.

[0137] Those skilled in the art can understand that, when the flow rate of hydrogen chloride gas does not change in a short period of time, increasing the water flow rate of the falling film absorber can reduce the temperature of the solution in the falling film absorber.

[0138] The control device can set multiple valve positions of the absorber inlet regulating valve in a gradient manner according to the magnitude of the temperature threshold exceeded by the falling film absorber. In this way, when the solution temperature of a certain falling film absorber exceeds the temperature, the control device can determine a valve position of a certain gradient as the starting valve position according to the corresponding relationship between the exceeded temperature and the valve position, and issue a corresponding control instruction to adjust the first absorber inlet regulating valve to the specified valve position.

[0139] Exemplarily, 10 valve positions with increasing gradients can be preset, corresponding to 10 ranges in which the temperature difference is greater than the preset temperature threshold. When the value of the temperature difference greater than the preset temperature threshold is within the range corresponding to the valve position of the 4th gradient, the valve position of the 4th gradient can be used as the starting valve position.

[0140] S503, executing the above steps at preset time intervals until the temperature difference is less than a preset temperature threshold, and then stopping adjusting the valve position of the first absorber water inlet regulating valve.

[0141] According to the above description, the first absorber temperature detection device detects the solution temperature in the first falling film absorber at preset time intervals and sends it to the control device. If the temperature difference is less than the preset threshold, that is, the actual solution temperature of the first falling film absorber is less than the target solution temperature, the temperature control of the falling film absorber can be stopped.

[0142] Otherwise, the valve position of the first absorber water inlet regulating valve of the first falling film absorber is adjusted to the valve position of the next gradient. For example, when the temperature was controlled last time, the corresponding valve position was the valve position of the 4th gradient, so this temperature control sets it to the valve position of the 5th gradient.

[0143] The first falling film absorber is any one of the multiple falling film absorbers, and the first absorber water inlet regulating valve is an absorber water inlet regulating valve corresponding to the first falling film absorber.

[0144] It can be understood that the temperature control process of the first falling film absorber by the control device can be executed on each falling film absorber simultaneously or sequentially.

[0145] Fig. 9 The figure shows the time variation curve of the solution temperature in a falling film absorber before the control device performs temperature control. Fig.10 The figure shows the curve of the solution temperature change over time in the same falling film absorber after the control device performs temperature control. Fig. 9 It can be seen that before temperature control is implemented, the temperature of the falling film absorber fluctuates greatly. When the preset temperature threshold is 45 degrees Celsius, over-temperature often occurs, which affects the absorption efficiency of hydrogen chloride gas and may cause hydrogen chloride gas to overflow due to insufficient absorption. Fig.10 It can be seen that after the control device uses temperature control, the temperature in the falling film absorber only fluctuates periodically and in a small range when the second acid tank is switched to the currently used acid tank, and no overtemperature occurs.

[0146] In this embodiment, the control device controls the temperature of the falling film absorber to ensure the temperature of the hydrogen chloride solution in the falling film absorber is stable, preventing the falling film absorber from affecting the absorption of hydrogen chloride gas due to overheating, thereby improving the safety and stability of the system.

[0147] Alternatively, if Fig.11 As shown, in the above step S402, the water inlet regulating valve of each absorber is adjusted according to the second liquid level value, the second actual concentration value and each actual solution temperature value, which can be achieved by the following steps S601 to S603.

[0148] S601, determining a second fitting concentration value of the first acid tank according to the second liquid level value.

[0149] Optionally, the control device may determine a second fitting concentration value corresponding to a second liquid level value in the first acid tank according to the above-mentioned liquid level-acid concentration fitting curve.

[0150] S602: If a second concentration difference between the second fitted concentration value and the second actual concentration value is greater than a first preset concentration threshold, then according to the second concentration difference and a preset adjustment coefficient, the valve position of the absorber water inlet regulating valve of the falling film absorber corresponding to the smallest actual solution temperature value among the actual solution temperature values ​​is reduced.

[0151] Further, the control device determines the second concentration difference value according to the difference between the second fitted concentration value and the second actual concentration value. As in the above embodiment, the second liquid level value and the second actual concentration value can be collected at a preset detection time interval and sent to the control device.

[0152] Exemplarily, the first preset concentration threshold C_CT may be a minimum concentration deviation value between the second fitting concentration value and the second actual concentration value. When the second concentration difference value is greater than the first preset concentration threshold C_CT, it can be understood that the second actual concentration value is less than the second fitting concentration value, and the deviation value is greater than the minimum concentration deviation value, and the concentration of the hydrogen chloride solution in the falling film absorber needs to be increased.

[0153] It can be understood by those skilled in the art that as the solution temperature of the falling film absorber increases, the absorption rate of the falling film absorber decreases. After sorting the solution temperatures of the falling film absorbers, the valve position of the absorber water inlet regulating valve of the falling film absorber with the lowest actual solution temperature value is reduced, so that the concentration of the falling film absorber can be increased, and the concentration of each falling film absorber whose actual solution temperature is higher than the actual solution temperature of the falling film absorber is ensured not to decrease.

[0154] Among them, the valve position adjustment amount of the valve position reduction is determined by the following formula according to the value of the second concentration difference exceeding C_CT and the preset adjustment coefficient. The control device outputs a control instruction to control the valve position of the corresponding absorber water inlet regulating valve to reduce the valve position adjustment amount according to the valve position adjustment amount.

[0155] S603, if a third concentration difference between the second actual concentration value and the second fitted concentration value is greater than a first preset concentration threshold, then according to the third concentration difference and a preset adjustment coefficient, the valve position of the absorber water inlet regulating valve of the falling film absorber corresponding to the largest actual solution temperature value among the actual solution temperature values ​​is increased.

[0156] Optionally, the control device may also determine a third concentration difference value according to a difference value between the second actual concentration value and the second fitted concentration value. The third concentration difference value is compared with the first preset concentration threshold value C_CT. If the third concentration difference value is greater than C_CT, it can be understood that the second actual concentration value is greater than the second fitted concentration value, and the deviation value is greater than the minimum concentration deviation value, and the concentration of the hydrogen chloride solution in the falling film absorber needs to be reduced.

[0157] Therefore, after sorting the solution temperatures of each falling film absorber, increasing the valve position of the absorber inlet regulating valve of the falling film absorber with the highest actual solution temperature value can reduce the concentration of the falling film absorber and ensure that the concentration of each falling film absorber whose actual solution temperature is lower than the actual solution temperature of the falling film absorber does not continue to increase.

[0158] When the valve position of the water inlet regulating valve of each falling film absorber is increased or decreased, the corresponding relationship between the valve position adjustment amount ΔMV and the concentration deviation value ΔCT can be expressed by the following formula:

[0159] ΔMV=K*ΔCT

[0160] Wherein, K is the adjustment coefficient, and its value is determined according to the required adjustment speed and accuracy.

[0161] The concentration control of steps S601 to S603 may be performed multiple times until the concentration value of the hydrogen chloride solution in the first acid tank is equal to the target concentration value.

[0162] Fig.12 It is a schematic diagram showing the matching relationship between the actual solution temperature curve and the actual liquid level curve in the first acid tank when the control device does not perform concentration control. Fig.13 The figure shows the matching relationship between the actual solution temperature curve and the actual liquid level curve in the first acid tank after the control device performs concentration control. Fig.12 It can be seen that when concentration control is not performed, the matching relationship between the actual solution concentration and the actual liquid level is poor, and the actual solution concentration increases too fast, the initial actual solution concentration is high, and the actual solution concentration increases slowly relative to the actual liquid level, resulting in the actual liquid level exceeding the upper limit of the first acid tank and still failing to meet the requirements. Fig.13 It can be seen that after concentration control, the actual solution concentration and the actual liquid level match well and can remain synchronized in multiple cycles.

[0163] In this embodiment, the control device performs concentration control so that when the concentration of the hydrogen chloride solution in the first acid tank reaches the target concentration, the actual solution concentration matches the actual liquid level. In this way, hydrochloric acid with the target concentration value can be obtained when the actual liquid level reaches the upper limit of the liquid level of the first acid tank, thereby reducing the acid tank switching frequency, reducing the output of unqualified hydrogen chloride solution, and improving the efficiency of producing hydrochloric acid.

[0164] Optionally, in the above step S301, before determining the first fitting concentration value of the hydrogen chloride solution in the first acid tank according to the first liquid level value of the first acid tank sent by the first liquid level detection device corresponding to the first acid tank, the method may further include: determining the first acid tank according to the states of the acid inlet shut-off valve and the acid outlet shut-off valve of each acid tank among the multiple acid tanks.

[0165] It is understandable that the acid tank currently used needs to be connected with falling film absorber, and the hydrogen chloride solution not in the preset normal interval is delivered to the current standby acid tank, therefore, the acid feed cut-off valve in each acid tank and a plurality of acid outlet cut-off valves are all open state. The acid feed cut-off valve of standby acid tank and other unused acid tanks and a plurality of acid outlet valves are all closed state.

[0166] It can be seen from the above description that the control device is communicatively connected with the acid inlet shut-off valve and the acid outlet shut-off valve of each acid tank. Therefore, the control device can mark the opening and closing status of each valve, and accordingly, the acid tank in which all valves are in the open state is used as the first acid tank, and one of the other acid tanks is used as a spare acid tank and marked.

[0167] In this embodiment, the control device directly, accurately and quickly determines the first acid tank currently in use through the states of the acid inlet shut-off valve and the acid outlet shut-off valve, thereby improving the working efficiency of the system.

[0168] Alternatively, if Fig.14 As shown, in the above step S304, switching the currently spare second acid tank to the currently used acid tank can be achieved by the following steps S701 to S702.

[0169] S701, control the second acid inlet cut-off valve and the second acid outlet cut-off valve of the second acid tank to open.

[0170] After the control device has executed the above-mentioned temperature control and concentration control process, when the concentration of the hydrogen chloride solution in the first acid tank reaches the target concentration value, and its liquid level reaches the first acid tank when the maximum liquid level, a control instruction can be sent to the second acid inlet shut-off valve and a plurality of second acid outlet shut-off valves of the second acid tank to open them, switch to the acid tank currently used, and continue to execute the steps in the above-described embodiment.

[0171] S702, controlling the first acid inlet cut-off valve and the first acid outlet cut-off valve of the first acid tank to close.

[0172] At the same time, the control device can send control instructions to the first acid inlet cut-off valve and multiple acid outlet cut-off valves of the first acid tank to close them and extract the hydrochloric acid in the first acid tank.

[0173] Optionally, after the control device completes the process of acid tank switching and hydrochloric acid collection, it can output a prompt screen of "grooving completed" to a display device connected thereto.

[0174] In this embodiment, hydrochloric acid with a liquid level and concentration that meet the requirements is automatically produced, and the spare acid tank is automatically switched to the acid tank currently in use, thereby improving the degree of automation in hydrochloric acid production.

[0175] See also Fig.15The embodiment of the present application also provides an automatic control device 10 for hydrochloric acid production, the device comprising:

[0176] The determination module 1001 is used to determine a first fitting concentration value of the hydrogen chloride solution in the first acid tank according to a first liquid level value of the first acid tank sent by a first liquid level detection device corresponding to the first acid tank, where the first acid tank is the acid tank currently used among the multiple acid tanks.

[0177] The determination module 1001 is also used to determine whether the concentration of the hydrogen chloride solution in the first acid tank is within a preset normal range according to a first concentration difference between the first fitting concentration value and a first actual concentration value of the hydrogen chloride solution in the first acid tank sent by a first concentration detection device corresponding to the first acid tank.

[0178] The regulating module 1002 is used to regulate the water inlet regulating valve of each absorber according to the actual solution temperature value of each falling film absorber sent by each absorber temperature detection device, the second liquid level value of the first acid tank sent by the first liquid level detection device, and the second actual concentration value of the hydrogen chloride solution in the first acid tank sent by the first concentration detection device.

[0179] The slot cutting module 1003 is used to switch the currently spare second acid tank to the currently used acid tank when the second actual concentration value is equal to the target concentration value.

[0180] The determination module 1001 is also specifically used to determine the first fitting concentration value corresponding to the first liquid level value in the liquid level acid concentration fitting curve according to the pre-obtained liquid level acid concentration fitting curve, and the liquid level acid concentration fitting curve is obtained by fitting the corresponding concentration values ​​of multiple groups of hydrogen chloride solutions with target concentrations at different liquid level values.

[0181] The regulating module 1002 is further specifically used to regulate the water inlet regulating valve of each absorber according to the temperature difference between each actual solution temperature value and the target solution temperature value, so that the actual solution temperature value of each falling film absorber meets the preset condition; and regulate the water inlet regulating valve of each absorber according to the second liquid level value, the second actual concentration value and each actual solution temperature value, so that the concentration of the hydrogen chloride solution in the first acid tank reaches the target concentration value.

[0182] The regulating module 1002 is also specifically used to determine whether the temperature difference between the actual solution temperature value and the target solution temperature value of the first falling film absorber is greater than a preset temperature threshold; if the temperature difference is greater than the preset temperature threshold, the valve position of the first absorber water inlet regulating valve is increased; at preset time intervals, the above steps are performed until the temperature difference is less than the preset temperature threshold, and the valve position of the first absorber water inlet regulating valve is stopped; the first falling film absorber is any one of the multiple falling film absorbers, and the first absorber water inlet regulating valve is the absorber water inlet regulating valve corresponding to the first falling film absorber.

[0183] The adjustment module 1002 is also specifically used to determine a second fitting concentration value of the first acid tank according to the second liquid level value; if a second concentration difference between the second fitting concentration value and the second actual concentration value is greater than a first preset concentration threshold, then according to the second concentration difference and the preset adjustment coefficient, the valve position of the absorber water inlet regulating valve of the falling film absorber corresponding to the smallest actual solution temperature value among the actual solution temperature values ​​is reduced; if a third concentration difference between the second actual concentration value and the second fitting concentration value is greater than the first preset concentration threshold, then according to the third concentration difference and the preset adjustment coefficient, the valve position of the absorber water inlet regulating valve of the falling film absorber corresponding to the largest actual solution temperature value among the actual solution temperature values ​​is increased.

[0184] The determination module 1001 is further specifically configured to determine the first acid tank according to the states of the acid inlet cut-off valve and the acid outlet cut-off valve of each of the multiple acid tanks.

[0185] The grooving module 1003 is also specifically used to control the second acid inlet cut-off valve and the second acid outlet cut-off valve of the second acid tank to open; and control the first acid inlet cut-off valve and the first acid outlet cut-off valve of the first acid tank to close.

[0186] See also Fig.16 This embodiment also provides a control device, which includes: a processor 2001, a memory 2002 and a bus. The memory 2002 stores machine-readable instructions executable by the processor 2001. When the control device is running, the above machine-readable instructions are executed. The processor 2001 communicates with the memory 2002 through the bus. The processor 2001 is used to execute the steps of the automatic control method for hydrochloric acid production in the above embodiment.

[0187] The memory 2002, the processor 2001 and the bus components are electrically connected to each other directly or indirectly to realize the transmission or interaction of data. For example, these components can be electrically connected to each other through one or more communication buses or signal lines. The automatic control device for hydrochloric acid production includes at least one software function module that can be stored in the memory 2002 in the form of software or firmware or solidified in the operating system (OS) of the control device. The processor 2001 is used to execute the executable modules stored in the memory 2002, such as the software function modules and computer programs included in the automatic control device for hydrochloric acid production.

[0188] Among them, the memory 2002 can be, but is not limited to, random access memory (Random Access Memory, RAM), read only memory (Read Only Memory, ROM), programmable read-only memory (Programmable Read-Only Memory, PROM), erasable programmable read-only memory (Erasable Programmable Read-Only Memory, EPROM), electrically erasable read-only memory (Electric Erasable Programmable Read-Only Memory, EEPROM), etc.

[0189] Optionally, the present application further provides a storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the above method embodiment are executed. The specific implementation method and technical effect are similar and will not be repeated here.

[0190] Those skilled in the art can clearly understand that, for the convenience and simplicity of description, the specific working process of the system and device described above can refer to the corresponding process in the method embodiment, and will not be repeated in this application. In the several embodiments provided in this application, it should be understood that the disclosed system, device and method can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the modules is only a logical function division. There may be other division methods in actual implementation. For example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some communication interfaces, indirect coupling or communication connection of devices or modules, which can be electrical, mechanical or other forms.

[0191] In addition, each functional unit in each embodiment of the present application can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a ROM, a RAM, a magnetic disk, or an optical disk.

[0192] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. An automatic control method for hydrochloric acid production, characterized in that: A control device for an automatic control system for hydrochloric acid production, the automatic control system for hydrochloric acid production comprising: the control device and a plurality of controlled devices, the plurality of controlled devices comprising: a plurality of falling film absorbers, a plurality of absorber temperature detection devices corresponding one-to-one to the plurality of falling film absorbers, a plurality of absorber water inlet regulating valves corresponding one-to-one to the plurality of falling film absorbers, a plurality of liquid level detection devices, a plurality of concentration detection devices, a plurality of acid inlet cut-off valves, a plurality of acid outlet cut-off valves and a plurality of acid tanks, the control device being respectively connected in communication with each of the controlled devices; The method comprises: Determine a first fitted concentration value of the hydrogen chloride solution in the first acid tank according to a first liquid level value of the first acid tank sent by a first liquid level detection device corresponding to the first acid tank, wherein the first acid tank is an acid tank currently used among the plurality of acid tanks; determining whether the concentration of the hydrogen chloride solution in the first acid tank is within a preset normal range according to a first concentration difference between the first fitted concentration value and a first actual concentration value of the hydrogen chloride solution in the first acid tank sent by a first concentration detection device corresponding to the first acid tank; If so, the water inlet regulating valves of the absorbers are adjusted according to the actual solution temperature values ​​of the falling film absorbers sent by the absorber temperature detection devices, the second liquid level value of the first acid tank sent by the first liquid level detection device, and the second actual concentration value of the hydrogen chloride solution in the first acid tank sent by the first concentration detection device; the second liquid level value and the second actual concentration value are obtained by the first liquid level detection device and the first concentration detection device detecting the liquid level and concentration of the hydrogen chloride solution in the first acid tank again at preset detection time intervals; When the second actual concentration value is equal to the target concentration value, the second acid tank currently in standby mode is switched to the acid tank currently in use; The method of determining a first fitted concentration value of the hydrogen chloride solution in the first acid tank according to a first liquid level value of the first acid tank sent by a first liquid level detection device corresponding to the first acid tank comprises: determining a first fitted concentration value corresponding to the first liquid level value in the liquid level acid concentration fitting curve according to a pre-obtained liquid level acid concentration fitting curve, wherein the liquid level acid concentration fitting curve is obtained by fitting according to the expected concentration values ​​of hydrogen chloride solutions of multiple groups of target concentrations at different liquid level values.

2. The automatic control method for hydrochloric acid production according to claim 1, characterized in that: The step of adjusting the water inlet regulating valve of each absorber according to the actual solution temperature value of each falling film absorber sent by each absorber temperature detection device, the second liquid level value of the first acid tank sent by the first liquid level detection device, and the second actual concentration value of the hydrogen chloride solution in the first acid tank sent by the concentration detection device comprises: According to the temperature difference between the actual solution temperature value and the target solution temperature value, the water inlet regulating valve of each absorber is adjusted respectively so that the actual solution temperature value of each falling film absorber meets the preset condition; According to the second liquid level value, the second actual concentration value and the actual solution temperature values, the water inlet regulating valves of the absorbers are adjusted respectively so that the concentration of the hydrogen chloride solution in the first acid tank reaches the target concentration value.

3. The automatic control method for hydrochloric acid production according to claim 2, characterized in that: The step of adjusting the water inlet regulating valves of the absorbers according to the temperature difference between the actual solution temperature values ​​and the target solution temperature values ​​comprises: Determining whether a temperature difference between an actual solution temperature value of the first falling film absorber and the target solution temperature value is greater than a preset temperature threshold; If the temperature difference is greater than a preset temperature threshold, increasing the valve position of the first absorber water inlet regulating valve; At preset time intervals, the above steps are performed until the temperature difference is less than the preset temperature threshold, and the valve position of the first absorber water inlet regulating valve is stopped; The first falling film absorber is any one of the plurality of falling film absorbers, and the first absorber water inlet regulating valve is an absorber water inlet regulating valve corresponding to the first falling film absorber.

4. The automatic control method for hydrochloric acid production according to claim 2, characterized in that: The step of adjusting the water inlet regulating valve of each absorber according to the second liquid level value, the second actual concentration value and each actual solution temperature value comprises: Determine a second fitting concentration value of the first acid tank according to the second liquid level value; If a second concentration difference between the second fitted concentration value and the second actual concentration value is greater than a first preset concentration threshold, reducing the valve position of the absorber water inlet regulating valve of the falling film absorber corresponding to the smallest actual solution temperature value among the actual solution temperature values ​​according to the second concentration difference and a preset adjustment coefficient; If a third concentration difference between the second actual concentration value and the second fitted concentration value is greater than a first preset concentration threshold, the valve position of the absorber water inlet regulating valve of the falling film absorber corresponding to the largest actual solution temperature value among the actual solution temperature values ​​is increased according to the third concentration difference and the preset adjustment coefficient.

5. The automatic control method for hydrochloric acid production according to claim 1, characterized in that: Before determining the first fitted concentration value of the hydrogen chloride solution in the first acid tank according to the first liquid level value of the first acid tank sent by the first liquid level detection device corresponding to the first acid tank, the method further includes: The first acid tank is determined according to the states of the acid inlet cut-off valve and the acid outlet cut-off valve of each of the multiple acid tanks.

6. The automatic control method for hydrochloric acid production according to claim 1, characterized in that: The step of switching the currently standby second acid tank to the currently used acid tank comprises: Controlling the second acid inlet cut-off valve and the second acid outlet cut-off valve of the second acid tank to open; The first acid inlet cut-off valve and the first acid outlet cut-off valve of the first acid tank are controlled to be closed.

7. An automatic control system for hydrochloric acid production, characterized in that: The system comprises: a control device and a plurality of controlled devices, wherein the plurality of controlled devices comprise: a plurality of falling film absorbers, a plurality of absorber temperature detection devices corresponding to the plurality of falling film absorbers one by one, a plurality of absorber water inlet regulating valves corresponding to the plurality of falling film absorbers one by one, a plurality of liquid level detection devices, a plurality of concentration detection devices, a plurality of acid inlet cut-off valves, a plurality of acid outlet cut-off valves and a plurality of acid tanks, and the control device is respectively connected in communication with each of the controlled devices; The control device is used to execute the automatic control method for hydrochloric acid production according to any one of claims 1 to 6; Each of the falling film absorbers is used to absorb hydrogen chloride gas to obtain a hydrogen chloride solution; The multiple absorber water inlet regulating valves are respectively used to adjust the water inlet flow rate of the corresponding falling film absorber; The multiple absorber temperature detection devices are respectively used to detect the temperature of the hydrogen chloride solution in the corresponding falling film absorber; The plurality of liquid level detection devices correspond one to one with the plurality of acid tanks, and each of the liquid level detection devices is used to detect the liquid level of the hydrogen chloride solution in the corresponding acid tank; The multiple concentration detection devices correspond to the multiple acid tanks one by one, and each of the concentration detection devices is used to detect the concentration of the hydrogen chloride solution in the corresponding acid tank; Each of the acid inlet cut-off valves and each of the acid outlet cut-off valves are used to control the inlet and outlet of the hydrogen chloride solution in the corresponding acid tank.

8. A control device, characterized in that: The control device includes: a processor, a storage medium and a bus, the storage medium stores machine-readable instructions executable by the processor, and when the control device is running, the processor communicates with the storage medium through the bus, and the processor executes the machine-readable instructions to perform the steps of the automatic control method for hydrochloric acid production as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the automatic control method for hydrochloric acid production as described in any one of claims 1 to 6.

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