Dynamic adjustment method for blow-off period of urea hydrolysis reactor

Abstract

The invention discloses a urea hydrolysis reactor pollution discharge cycle dynamic adjustment method, which comprises: obtaining historical pollutant accumulation concentrations at a plurality of preset positions, and obtaining historical operation parameters at the same time; based on the synchronous change evaluation values of the historical pollutant accumulation concentration and the historical operation parameters, historical characteristic parameters are screened out, and a pollutant accumulation concentration prediction model of the urea hydrolysis reactor is established; determining a predicted pollutant accumulation concentration according to a pollutant accumulation concentration model, comparing the predicted pollutant accumulation concentration with a preset pollutant accumulation concentration, and obtaining a first adjusted pollution discharge period according to a comparison result; performing analogue simulation on the first adjustment pollution discharge period to obtain a first virtual influence coefficient and a second virtual influence coefficient, and generating virtual availability of the first adjustment pollution discharge period; according to the virtual availability, whether the first adjustment pollution discharge period is corrected or not is judged, if yes, a second adjustment pollution discharge period is generated, and the performance and safety of the urea hydrolysis reactor are improved.

Description

Technical Field

[0001] The present application relates to the technical field of urea hydrolysis systems, and in particular to a method for dynamically adjusting the sewage discharge period of a urea hydrolysis reactor. Background Art

[0002] The urea hydrolysis system is a system in which a urea solution with a mass concentration of about 50% is delivered to a hydrolysis reactor for producing ammonia by a urea solution delivery pump. Saturated steam heats the urea solution through a tube bundle to provide a heat source for urea hydrolysis. The urea solution undergoes a hydrolysis reaction under set temperature and pressure conditions to generate a gaseous mixture containing ammonia. After decompression, the mixture is sent to a metering and regulating module and then to an SCR reactor for flue gas denitrification. However, urea contains a certain degree of pollutants, which will accumulate in the hydrolyzer. It is necessary to formulate a discharge cycle to achieve regular discharge of pollutants from the urea hydrolysis reactor. In the prior art, a fixed discharge cycle is usually set based on experience and cannot be dynamically adjusted based on the actual situation of the pollutants, resulting in excessive accumulation of pollutants and reduced performance and safety of the urea hydrolysis reactor. Summary of the invention

[0003] In order to solve the above technical problems, the present application provides a method for dynamically adjusting the discharge cycle of a urea hydrolysis reactor. Through the synchronous change evaluation value of the historical pollutant accumulation concentration and the historical operating parameters, the historical characteristic parameters are screened out and a pollutant accumulation concentration prediction model is established. The predicted pollutant accumulation concentration is obtained according to the pollutant accumulation concentration prediction model, and a first adjusted discharge cycle is formulated. The first adjusted discharge cycle is simulated, and a virtual availability is generated according to the simulation results. It is determined whether to adjust the first adjusted discharge cycle again according to the virtual availability, and the discharge cycle is dynamically adjusted according to the pollutant accumulation concentration inside the urea hydrolysis reactor to improve the performance and safety of the urea hydrolysis reactor.

[0004] In some embodiments of the present application, a method for dynamically adjusting the sewage discharge period of a urea hydrolysis reactor is provided, comprising:

[0005] Obtaining historical pollutant accumulation concentrations at multiple preset locations inside the urea hydrolysis reactor, and simultaneously obtaining historical operating parameters of the urea hydrolysis system;

[0006] Based on the synchronous change evaluation values ​​of historical pollutant accumulation concentrations and historical operating parameters, historical characteristic parameters are screened out, and a pollutant accumulation concentration prediction model is established based on the historical characteristic parameters and historical pollutant accumulation concentrations;

[0007] Determine a predicted pollutant accumulation concentration according to a pollutant accumulation concentration prediction model, compare the predicted pollutant accumulation concentration with a preset pollutant accumulation concentration of a preset pollutant discharge cycle, and adjust the preset pollutant discharge cycle according to the comparison result to obtain a first adjusted pollutant discharge cycle;

[0008] Simulating the first adjustment and discharge cycle to obtain a first virtual influence coefficient and a second virtual influence coefficient, and generating a virtual availability of the first adjustment and discharge cycle;

[0009] It is determined whether to modify the first adjustment emission cycle according to the virtual availability, and if so, a second adjustment emission cycle is generated.

[0010] In some embodiments of the present application, historical characteristic parameters are screened out, including:

[0011] Obtain historical pollutant accumulation concentrations at multiple preset locations within the same historical period and historical operating parameters within the corresponding historical period;

[0012] Taking the historical period as the time reference line, multiple preset collection nodes are set according to the preset detection accuracy, and the historical pollutant accumulation concentration and historical operation parameters at the preset collection nodes are collected and mapped onto the time reference line;

[0013] Analyze the historical pollutant accumulation concentrations at multiple preset collection nodes at the same preset location, select the preset collection nodes whose first change degree is greater than the preset first change degree threshold, and obtain the second change degree of the historical operating parameters at the selected preset collection nodes;

[0014] Determine, according to the second degree of change, the synchronous change time nodes and synchronous change degrees of the historical pollutant cumulative concentration and the historical operating parameters at the plurality of preset collection nodes at each preset location;

[0015] Generate synchronous change evaluation values ​​of historical pollutant accumulation concentrations and corresponding historical operating parameters at corresponding preset locations according to synchronous change time nodes and synchronous change degrees;

[0016] The historical operation parameter whose synchronous change evaluation value is greater than the preset synchronous change evaluation value threshold is set as the pending characteristic parameter of the historical pollutant accumulation concentration corresponding to the preset location;

[0017] The pending characteristic parameters determined by the historical pollutant accumulation concentrations at each preset location are compared, and the pending characteristic parameters with a repetition degree greater than a preset repetition degree threshold are screened out according to the comparison results and set as the historical characteristic parameters.

[0018] In some embodiments of the present application, the calculation formula of the synchronous change evaluation value is:

[0019]

[0020] Wherein, T is the synchronous change evaluation value, t0 is the synchronous change evaluation conversion coefficient, m is the number of synchronous change time nodes of historical pollutant cumulative concentration and historical operation parameters, n is the preset collection node that screens out the first change degree greater than the preset first change degree threshold, b1i is the first change degree of the historical pollutant cumulative concentration at the i-th synchronous change time node, B1 is the preset first change degree threshold, b2i is the second change degree of the historical operation parameter at the i-th synchronous change time node, B2 is the preset second change degree threshold, is the degree of synchronization change at the i-th synchronization change time node.

[0021] In some embodiments of the present application, a pollutant accumulation concentration prediction model is established, including:

[0022] Obtain the past preset sewage discharge cycle operation log of the urea hydrolysis reactor, and filter out the historical pollutant accumulation concentration and corresponding historical characteristic parameters in the past preset sewage discharge cycle operation log according to the preset collection node;

[0023] Using multiple historical characteristic parameters at the same preset collection node as a training input parameter set, and using the historical pollutant accumulation concentration at the corresponding preset collection node as a training output parameter set;

[0024] Based on the training input parameter set and the training output parameter set, neural network training is performed to obtain a pollutant accumulation concentration prediction model.

[0025] In some embodiments of the present application, adjusting the preset sewage discharge cycle according to the comparison result to obtain a first adjusted sewage discharge cycle includes:

[0026] Acquire real-time characteristic parameters within a preset period of time, input the real-time characteristic parameters into a pollutant accumulation concentration prediction model, and obtain a predicted pollutant accumulation concentration within the preset period of time;

[0027] Generate a difference evaluation value between the predicted pollutant accumulation concentration and the preset pollutant accumulation concentration according to the change rate of the predicted pollutant accumulation concentration within the preset time period and the maximum concentration difference between the predicted pollutant accumulation concentration and the preset pollutant accumulation concentration;

[0028] Setting a first adjustment coefficient for a preset sewage discharge cycle according to the difference evaluation value;

[0029] Presetting a first preset difference evaluation value interval, a second preset difference evaluation value interval, a third preset difference evaluation value interval and a fourth preset difference evaluation value interval;

[0030] When the difference evaluation value is within the first preset difference evaluation value interval, the fourth preset adjustment coefficient z4 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle V0*z4;

[0031] When the difference evaluation value is in the second preset difference evaluation value interval, the third preset adjustment coefficient z3 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle of V0*z3;

[0032] When the difference evaluation value is in the third preset difference evaluation value interval, the second preset adjustment coefficient z2 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle of V0*z2;

[0033] When the difference evaluation value is in the fourth preset difference evaluation value interval, the first preset adjustment coefficient z1 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle V0*z1;

[0034] Among them, the first preset difference evaluation value interval < the second preset difference evaluation value interval < 0 < the third preset difference evaluation value < the fourth preset difference evaluation value interval, 0.65 < z1 < z2 < 1 < z3 < z4 < 1.35.

[0035] In some embodiments of the present application, the simulation of the first adjustment and discharge cycle includes:

[0036] Acquire equipment information and connection information of the urea hydrolysis system, and construct a urea hydrolysis system simulation model of the urea hydrolysis system based on real-time operation data of the urea hydrolysis system and a preset modeling method;

[0037] Based on the position information of the preset position and the corresponding predicted pollutant accumulation concentration, a corresponding position inside the urea hydrolysis reactor in the urea hydrolysis system simulation model is marked;

[0038] According to the first functional relationship between the historical characteristic parameters and the historical pollutant accumulation concentration, and the second functional relationship between the historical pollution discharge cycle and the historical operation data in the previous preset pollution discharge cycle operation log, the historical correlation relationship between the historical pollutant accumulation concentration, the historical characteristic parameters and the historical operation data in each historical pollution discharge cycle is obtained;

[0039] Acquire the dynamic information to be set according to the first adjustment pollutant discharge cycle, and establish a predicted dynamic relationship between the dynamic information to be set and the predicted pollutant accumulation concentration, the real-time characteristic parameters, and the real-time operation data;

[0040] The predicted dynamic relationship is linked to the urea hydrolysis system simulation model to perform a simulation of the first adjustment and discharge cycle.

[0041] In some embodiments of the present application, obtaining the first virtual influence coefficient and the second virtual influence coefficient includes:

[0042] According to the historical operation log of the urea hydrolysis system, first relevant operation data having a correlation degree with the operation efficiency index greater than a first preset correlation strength is selected, and second relevant operation data having a correlation degree with the ammonia demand index greater than a second preset correlation strength is selected;

[0043] Acquire simulated first relevant operation data after the first adjustment sewage discharge cycle is simulated, compare the simulated first relevant operation data with a preset standard operation data interval, and generate a first virtual influence coefficient according to the comparison result;

[0044] Acquire simulated second related operation data after the first adjustment sewage discharge cycle is simulated, compare the simulated second related operation data with a preset standard operation data interval, and generate a second virtual influence coefficient according to the comparison result.

[0045] In some embodiments of the present application, generating a virtual availability of a first adjustment blowdown period includes:

[0046] Generate a virtual availability of a first adjustment pollution discharge period according to a virtual decrease rate of the predicted pollutant accumulation concentration at each preset location, a first virtual influence coefficient, and a second virtual influence coefficient;

[0047] The calculation formula of the virtual availability is:

[0048] Y = c1*w1+*w2*c2+w3*c3;

[0049] Among them, Y is the virtual availability, w1 is the virtual decline rate, c1 is the weight coefficient of the virtual decline rate, w2 is the first virtual influence coefficient, c2 is the weight coefficient of the first virtual influence coefficient, w3 is the second virtual influence coefficient, and c3 is the weight coefficient of the second virtual influence coefficient.

[0050] In some embodiments of the present application, judging whether to modify the first adjustment pollution discharge cycle according to the virtual availability includes:

[0051] Pre-set virtual availability threshold;

[0052] If the virtual availability is less than the virtual availability threshold, a second adjustment coefficient is set according to the availability difference between the virtual availability threshold and the virtual availability, and the first adjustment discharge cycle is corrected to obtain a second adjustment discharge cycle;

[0053] If the virtual availability is greater than the virtual availability threshold, the first adjustment discharge cycle is not corrected.

[0054] Compared with the prior art, the method for dynamically adjusting the sewage discharge period of a urea hydrolysis reactor in the embodiment of the present application has the following beneficial effects:

[0055] Through the synchronous change evaluation values ​​of historical pollutant accumulation concentrations and historical operating parameters, historical characteristic parameters are screened out and a pollutant accumulation concentration prediction model is established. The predicted pollutant accumulation concentration is obtained according to the pollutant accumulation concentration prediction model, and the first adjustment discharge cycle is formulated. The first adjustment discharge cycle is simulated, and virtual availability is generated according to the simulation results. It is determined whether to adjust the first adjustment discharge cycle again according to the virtual availability. The discharge cycle is dynamically adjusted according to the pollutant accumulation concentration inside the urea hydrolysis reactor to improve the performance and safety of the urea hydrolysis reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 It is a flow chart of a method for dynamically adjusting the sewage discharge period of a urea hydrolysis reactor in a preferred embodiment of the present application. DETAILED DESCRIPTION

[0057] The specific implementation methods of the present application are further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but are not intended to limit the scope of the present application.

[0058] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0059] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0060] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0061] like Figure 1As shown, a method for dynamically adjusting the sewage discharge period of a urea hydrolysis reactor according to a preferred embodiment of the present application includes:

[0062] Step S101: obtaining historical pollutant accumulation concentrations at multiple preset positions inside a urea hydrolysis reactor, and simultaneously obtaining historical operating parameters of the urea hydrolysis system;

[0063] Step S102: based on the synchronous change evaluation value of the historical pollutant accumulation concentration and the historical operation parameter, the historical characteristic parameters are screened out, and based on the historical characteristic parameters and the historical pollutant accumulation concentration, a pollutant accumulation concentration prediction model is established;

[0064] Step S103: determining a predicted pollutant accumulation concentration according to a pollutant accumulation concentration prediction model, comparing the predicted pollutant accumulation concentration with a preset pollutant accumulation concentration of a preset pollutant discharge cycle, and adjusting the preset pollutant discharge cycle according to the comparison result to obtain a first adjusted pollutant discharge cycle;

[0065] Step S104: simulating the first adjustment sewage discharge cycle to obtain a first virtual influence coefficient and a second virtual influence coefficient, and generating a virtual availability of the first adjustment sewage discharge cycle;

[0066] Step S105: judging whether to modify the first adjustment emission cycle according to the virtual availability, and if so, generating a second adjustment emission cycle.

[0067] In this embodiment, the preset position refers to the position in the urea hydrolysis reactor where pollutants are easily accumulated, and is set in advance according to the historical pollutant accumulation position. The historical pollutant accumulation concentration is based on the measurement of multiple pollutant concentrations generated during the urea hydrolysis reaction using specific instruments. For example, the concentration of biuret is measured by a 752N spectrophotometer, copper sulfate, and potassium sodium tartrate.

[0068] In this embodiment, the preset pollution discharge cycle refers to the previous pollution discharge cycle before adjustment, which refers to the cycle of pollution discharge activities according to the previous specified time interval, and the preset pollutant accumulation concentration refers to the pollutant accumulation concentration based on which the previous pollution discharge cycle was set.

[0069] In this embodiment, historical characteristic parameters are screened out and a pollutant accumulation concentration prediction model is established through the evaluation value of the synchronous change of historical pollutant accumulation concentration and historical operating parameters. The predicted pollutant accumulation concentration is obtained according to the pollutant accumulation concentration prediction model, and a first adjustment discharge cycle is formulated. The first adjustment discharge cycle is simulated, and a virtual availability is generated according to the simulation results. According to the virtual availability, it is determined whether to adjust the first adjustment discharge cycle again. If it is adjusted again, a second adjustment discharge cycle is generated, and discharge is carried out according to the second adjustment discharge cycle. The discharge cycle is dynamically adjusted according to the pollutant accumulation concentration inside the urea hydrolysis reactor to improve the performance and safety of the urea hydrolysis reactor.

[0070] In some embodiments of the present application, historical characteristic parameters are screened out, including:

[0071] Obtain historical pollutant accumulation concentrations at multiple preset locations within the same historical period and historical operating parameters within the corresponding historical period;

[0072] Taking the historical period as the time reference line, multiple preset collection nodes are set according to the preset detection accuracy, and the historical pollutant accumulation concentration and historical operation parameters at the preset collection nodes are collected and mapped onto the time reference line;

[0073] Analyze the historical pollutant accumulation concentrations at multiple preset collection nodes at the same preset location, select the preset collection nodes whose first change degree is greater than the preset first change degree threshold, and obtain the second change degree of the historical operating parameters at the selected preset collection nodes;

[0074] Determine, according to the second degree of change, the synchronous change time nodes and synchronous change degrees of the historical pollutant cumulative concentration and the historical operating parameters at the plurality of preset collection nodes at each preset location;

[0075] Generate synchronous change evaluation values ​​of historical pollutant accumulation concentrations and corresponding historical operating parameters at corresponding preset locations according to synchronous change time nodes and synchronous change degrees;

[0076] The historical operation parameter whose synchronous change evaluation value is greater than the preset synchronous change evaluation value threshold is set as the pending characteristic parameter of the historical pollutant accumulation concentration corresponding to the preset location;

[0077] The pending characteristic parameters determined by the historical pollutant accumulation concentrations at each preset location are compared, and the pending characteristic parameters with a repetition degree greater than a preset repetition degree threshold are screened out according to the comparison results and set as the historical characteristic parameters.

[0078] In this embodiment, if the second change degree of the historical operating parameters at the screened preset collection node is greater than the preset second change degree threshold, the corresponding preset collection node is set as the synchronous change node of the corresponding historical operating parameters and the historical pollutant accumulation concentration at the corresponding preset position, and the synchronous change degree refers to the difference in the degree of change between the first change degree being greater than the preset first change degree threshold / the second change degree being greater than the preset second change degree threshold.

[0079] In this embodiment, according to the synchronous change evaluation values ​​of the historical pollutant accumulation concentration and the historical operating parameters at multiple preset collection nodes at each preset position, the correlation between the historical pollutant accumulation concentration and the historical operating parameters is obtained, thereby screening out the historical characteristic parameters, laying the foundation for the subsequent establishment of a pollutant accumulation concentration prediction model, reducing the amount of data monitoring and processing, accurately obtaining the changing relationship between the operating parameters of the urea hydrolysis system and the historical pollutant accumulation concentration, accurately predicting the pollutant accumulation concentration based on the real-time characteristic parameters, accurately adjusting the sewage discharge cycle, and improving the performance and safety of the urea hydrolysis reactor.

[0080] In some embodiments of the present application, the calculation formula of the synchronous change evaluation value is:

[0081]

[0082] Wherein, T is the synchronous change evaluation value, t0 is the synchronous change evaluation conversion coefficient, m is the number of synchronous change time nodes of historical pollutant cumulative concentration and historical operation parameters, n is the preset collection node that screens out the first change degree greater than the preset first change degree threshold, b1i is the first change degree of the historical pollutant cumulative concentration at the i-th synchronous change time node, B1 is the preset first change degree threshold, b2i is the second change degree of the historical operation parameter at the i-th synchronous change time node, B2 is the preset second change degree threshold, is the degree of synchronization change at the i-th synchronization change time node.

[0083] In some embodiments of the present application, a pollutant accumulation concentration prediction model is established, including:

[0084] Obtain the past preset sewage discharge cycle operation log of the urea hydrolysis reactor, and filter out the historical pollutant accumulation concentration and corresponding historical characteristic parameters in the past preset sewage discharge cycle operation log according to the preset collection node;

[0085] Using multiple historical characteristic parameters at the same preset collection node as a training input parameter set, and using the historical pollutant accumulation concentration at the corresponding preset collection node as a training output parameter set;

[0086] Based on the training input parameter set and the training output parameter set, neural network training is performed to obtain a pollutant accumulation concentration prediction model.

[0087] In this embodiment, a pollutant accumulation concentration prediction model is constructed through multiple historical pollutant accumulation concentrations and corresponding multiple historical characteristic parameters in the past preset sewage discharge cycle operation logs, laying the foundation for the subsequent generation of the first adjusted sewage discharge cycle, accurately realizing the dynamic adjustment of the sewage discharge cycle, and improving the performance of the urea hydrolysis reactor.

[0088] In some embodiments of the present application, adjusting the preset sewage discharge cycle according to the comparison result to obtain a first adjusted sewage discharge cycle includes:

[0089] Acquire real-time characteristic parameters within a preset period of time, input the real-time characteristic parameters into a pollutant accumulation concentration prediction model, and obtain a predicted pollutant accumulation concentration within the preset period of time;

[0090] Generate a difference evaluation value between the predicted pollutant accumulation concentration and the preset pollutant accumulation concentration according to the change rate of the predicted pollutant accumulation concentration within the preset time period and the maximum concentration difference between the predicted pollutant accumulation concentration and the preset pollutant accumulation concentration;

[0091] Setting a first adjustment coefficient for a preset sewage discharge cycle according to the difference evaluation value;

[0092] Presetting a first preset difference evaluation value interval, a second preset difference evaluation value interval, a third preset difference evaluation value interval and a fourth preset difference evaluation value interval;

[0093] When the difference evaluation value is within the first preset difference evaluation value interval, the fourth preset adjustment coefficient z4 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle V0*z4;

[0094] When the difference evaluation value is in the second preset difference evaluation value interval, the third preset adjustment coefficient z3 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle of V0*z3;

[0095] When the difference evaluation value is in the third preset difference evaluation value interval, the second preset adjustment coefficient z2 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle of V0*z2;

[0096] When the difference evaluation value is in the fourth preset difference evaluation value interval, the first preset adjustment coefficient z1 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle V0*z1;

[0097] Among them, the first preset difference evaluation value interval < the second preset difference evaluation value interval < 0 < the third preset difference evaluation value < the fourth preset difference evaluation value interval, 0.65 < z1 < z2 < 1 < z3 < z4 < 1.35.

[0098] In this embodiment, the preset pollutant discharge cycle refers to a cycle for performing pollutant discharge activities according to a previously specified time interval, and the first adjustment coefficient is set to adjust the time interval specified in the preset pollutant discharge cycle to obtain a first adjusted pollutant discharge cycle.

[0099] In this embodiment, when the preset difference evaluation value interval is less than 0, it means that the predicted pollutant cumulative concentration is less than the preset pollutant cumulative concentration and the change rate of the predicted pollutant cumulative concentration is small, then the difference evaluation value is negative, when the preset difference evaluation value interval in which the difference evaluation value is located is a negative value, the time interval specified in the preset pollution discharge cycle should be increased, when the preset difference evaluation value interval in which the difference evaluation value is located is a positive value, it means that the predicted pollutant cumulative concentration is greater than the preset pollutant cumulative concentration or the change rate of the predicted pollutant cumulative concentration is large, and the time interval specified in the preset pollution discharge cycle should be increased, thereby obtaining the first adjusted pollution discharge cycle, dynamically adjusting the pollution discharge cycle according to the actual situation of the pollutant cumulative concentration, and improving the pollution discharge efficiency and operation efficiency of the urea hydrolysis reactor under the premise of ensuring the pollutant emission standards.

[0100] In some embodiments of the present application, the simulation of the first adjustment and discharge cycle includes:

[0101] Acquire equipment information and connection information of the urea hydrolysis system, and construct a urea hydrolysis system simulation model of the urea hydrolysis system based on real-time operation data of the urea hydrolysis system and a preset modeling method;

[0102] Based on the position information of the preset position and the corresponding predicted pollutant accumulation concentration, a corresponding position inside the urea hydrolysis reactor in the urea hydrolysis system simulation model is marked;

[0103] According to the first functional relationship between the historical characteristic parameters and the historical pollutant accumulation concentration, and the second functional relationship between the historical pollution discharge cycle and the historical operation data in the previous preset pollution discharge cycle operation log, the historical correlation relationship between the historical pollutant accumulation concentration, the historical characteristic parameters and the historical operation data in each historical pollution discharge cycle is obtained;

[0104] Acquire the dynamic information to be set according to the first adjustment pollutant discharge cycle, and establish a predicted dynamic relationship between the dynamic information to be set and the predicted pollutant accumulation concentration, the real-time characteristic parameters, and the real-time operation data;

[0105] The predicted dynamic relationship is linked to the urea hydrolysis system simulation model to perform a simulation of the first adjustment and discharge cycle.

[0106] In this embodiment, the urea hydrolysis system simulation model refers to the actual scenario and actual operation of the urea hydrolysis reactor and the equipment involved in the urea hydrolysis system. By predicting the dynamic relationship and the urea hydrolysis system simulation model, a simulated sewage discharge process of the current first adjustment sewage discharge cycle is built, so as to obtain the influence of the subsequent first adjustment sewage discharge cycle on the operating efficiency, ammonia demand and accumulated concentration of pollutants of the urea hydrolysis system. This is conducive to discovering and improving the shortcomings of the first adjustment sewage discharge cycle, improving the sewage discharge efficiency of the urea hydrolysis reactor and the operating efficiency of the urea hydrolysis system, thereby improving the performance and safety of the urea hydrolysis reactor.

[0107] In some embodiments of the present application, obtaining the first virtual influence coefficient and the second virtual influence coefficient includes:

[0108] According to the historical operation log of the urea hydrolysis system, first relevant operation data having a correlation degree with the operation efficiency index greater than a first preset correlation strength is selected, and second relevant operation data having a correlation degree with the ammonia demand index greater than a second preset correlation strength is selected;

[0109] Acquire simulated first relevant operation data after the first adjustment sewage discharge cycle is simulated, compare the simulated first relevant operation data with a preset standard operation data interval, and generate a first virtual influence coefficient according to the comparison result;

[0110] Acquire simulated second related operation data after the first adjustment sewage discharge cycle is simulated, compare the simulated second related operation data with a preset standard operation data interval, and generate a second virtual influence coefficient according to the comparison result.

[0111] In this embodiment, the first relevant operating data refers to data that has an impact on evaluating the operating efficiency index of the urea hydrolysis system. The first preset correlation strength is set in advance, and the weight coefficient of the corresponding first relevant operating data is set according to the difference between the correlation strength with the operating efficiency index and the first preset correlation strength.

[0112] In this embodiment, the second relevant operating data refers to the influencing data for evaluating whether the ammonia demand index meets the preset demand. The second preset correlation strength is set in advance, and the weight coefficient of the corresponding second relevant operating data is set according to the difference between the correlation strength with the ammonia demand index and the second preset correlation strength.

[0113] In this embodiment, the first virtual influence coefficient is generated based on the difference between the simulated first relevant operating data and the simulated first relevant operating data in a pre-set standard operating data interval and the corresponding weight coefficient. When the difference between the simulated first relevant operating data is smaller, the first virtual influence coefficient is smaller, indicating that the first adjustment sewage discharge cycle has less impact on the operating efficiency of the urea hydrolysis system.

[0114] In this embodiment, the second virtual influence coefficient is generated based on the difference between the simulated second relevant operating data and the simulated second relevant operating data in a pre-set standard operating data interval and the corresponding weight coefficient. When the difference between the simulated second relevant operating data is smaller, the second virtual influence coefficient is smaller, indicating that the first adjustment of the sewage discharge cycle has less impact on whether the ammonia demand is met.

[0115] In some embodiments of the present application, generating a virtual availability of a first adjustment blowdown period includes:

[0116] Generate a virtual availability of a first adjustment pollution discharge period according to a virtual decrease rate of the predicted pollutant accumulation concentration at each preset location, a first virtual influence coefficient, and a second virtual influence coefficient;

[0117] The calculation formula of the virtual availability is:

[0118] Y = c1*w1+*w2*c2+w3*c3;

[0119] Among them, Y is the virtual availability, w1 is the virtual decline rate, c1 is the weight coefficient of the virtual decline rate, w2 is the first virtual influence coefficient, c2 is the weight coefficient of the first virtual influence coefficient, w3 is the second virtual influence coefficient, and c3 is the weight coefficient of the second virtual influence coefficient.

[0120] In this embodiment, the virtual decline rate is obtained by averaging the virtual decline rates of the predicted pollutant accumulation concentrations at multiple preset positions, c1+c2+c3=1, and the application effect of the first adjusted sewage discharge cycle is evaluated based on the virtual availability of the first adjusted sewage discharge cycle, so as to determine whether to adjust the first adjusted sewage discharge cycle again to improve the sewage discharge efficiency and operation efficiency of the urea hydrolysis reactor.

[0121] In some embodiments of the present application, judging whether to modify the first adjustment pollution discharge cycle according to the virtual availability includes:

[0122] Pre-set virtual availability threshold;

[0123] If the virtual availability is less than the virtual availability threshold, a second adjustment coefficient is set according to the availability difference between the virtual availability threshold and the virtual availability, and the first adjustment discharge cycle is corrected to obtain a second adjustment discharge cycle;

[0124] If the virtual availability is greater than the virtual availability threshold, the first adjustment discharge cycle is not corrected.

[0125] In this embodiment, if adjustment is made again, a second adjusted discharge cycle is generated, and discharge is performed according to the second adjusted discharge cycle. The discharge cycle is dynamically adjusted according to the accumulated concentration of pollutants inside the urea hydrolysis reactor to improve the performance and safety of the urea hydrolysis reactor.

[0126] The above is only a preferred implementation of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present application. These improvements and substitutions should also be regarded as the scope of protection of the present application.

Claims

1. A method for dynamically adjusting the blowdown cycle of a urea hydrolysis reactor, characterized in that: include: Obtaining historical pollutant accumulation concentrations at multiple preset locations inside the urea hydrolysis reactor, and simultaneously obtaining historical operating parameters of the urea hydrolysis system; Based on the synchronous change evaluation values ​​of historical pollutant accumulation concentrations and historical operating parameters, historical characteristic parameters are screened out, and a pollutant accumulation concentration prediction model is established based on the historical characteristic parameters and historical pollutant accumulation concentrations; Determine a predicted pollutant accumulation concentration according to a pollutant accumulation concentration prediction model, compare the predicted pollutant accumulation concentration with a preset pollutant accumulation concentration of a preset pollutant discharge cycle, and adjust the preset pollutant discharge cycle according to the comparison result to obtain a first adjusted pollutant discharge cycle; Simulating the first adjustment and discharge cycle to obtain a first virtual influence coefficient and a second virtual influence coefficient, and generating a virtual availability of the first adjustment and discharge cycle; It is determined whether to modify the first adjustment emission cycle according to the virtual availability, and if so, a second adjustment emission cycle is generated.

2. The method for dynamically adjusting the discharge cycle of a urea hydrolysis reactor according to claim 1, characterized in that: Filter out historical characteristic parameters, including: Obtain historical pollutant accumulation concentrations at multiple preset locations within the same historical period and historical operating parameters within the corresponding historical period; Taking the historical period as the time reference line, multiple preset collection nodes are set according to the preset detection accuracy, and the historical pollutant accumulation concentration and historical operation parameters at the preset collection nodes are collected and mapped onto the time reference line; Analyze the historical pollutant accumulation concentrations at multiple preset collection nodes at the same preset location, select the preset collection nodes whose first change degree is greater than the preset first change degree threshold, and obtain the second change degree of the historical operating parameters at the selected preset collection nodes; Determine, according to the second degree of change, the synchronous change time nodes and synchronous change degrees of the historical pollutant cumulative concentration and the historical operating parameters at the plurality of preset collection nodes at each preset location; Generate synchronous change evaluation values ​​of historical pollutant accumulation concentrations and corresponding historical operating parameters at corresponding preset locations according to synchronous change time nodes and synchronous change degrees; The historical operation parameter whose synchronous change evaluation value is greater than the preset synchronous change evaluation value threshold is set as the pending characteristic parameter of the historical pollutant accumulation concentration corresponding to the preset location; The pending characteristic parameters determined by the historical pollutant accumulation concentrations at each preset location are compared, and the pending characteristic parameters with a repetition degree greater than a preset repetition degree threshold are screened out according to the comparison results and set as the historical characteristic parameters.

3. The method for dynamically adjusting the discharge cycle of a urea hydrolysis reactor according to claim 2, characterized in that: The calculation formula of the synchronous change evaluation value is: Wherein, T is the synchronous change evaluation value, t0 is the synchronous change evaluation conversion coefficient, m is the number of synchronous change time nodes of historical pollutant cumulative concentration and historical operation parameters, n is the preset collection node that screens out the first change degree greater than the preset first change degree threshold, b1i is the first change degree of the historical pollutant cumulative concentration at the i-th synchronous change time node, B1 is the preset first change degree threshold, b2i is the second change degree of the historical operation parameter at the i-th synchronous change time node, B2 is the preset second change degree threshold, is the degree of synchronization change at the i-th synchronization change time node.

4. The method for dynamically adjusting the discharge cycle of a urea hydrolysis reactor according to claim 3, characterized in that: Establish a pollutant accumulation concentration prediction model, including: Obtain the past preset sewage discharge cycle operation log of the urea hydrolysis reactor, and filter out the historical pollutant accumulation concentration and corresponding historical characteristic parameters in the past preset sewage discharge cycle operation log according to the preset collection node; Using multiple historical characteristic parameters at the same preset collection node as a training input parameter set, and using the historical pollutant accumulation concentration at the corresponding preset collection node as a training output parameter set; Based on the training input parameter set and the training output parameter set, neural network training is performed to obtain a pollutant accumulation concentration prediction model.

5. The method for dynamically adjusting the sewage discharge period of a urea hydrolysis reactor according to claim 4, characterized in that: The preset sewage discharge cycle is adjusted according to the comparison result to obtain a first adjusted sewage discharge cycle, including: Acquire real-time characteristic parameters within a preset period of time, input the real-time characteristic parameters into a pollutant accumulation concentration prediction model, and obtain a predicted pollutant accumulation concentration within the preset period of time; Generate a difference evaluation value between the predicted pollutant accumulation concentration and the preset pollutant accumulation concentration according to the change rate of the predicted pollutant accumulation concentration within the preset time period and the maximum concentration difference between the predicted pollutant accumulation concentration and the preset pollutant accumulation concentration; Setting a first adjustment coefficient for a preset sewage discharge cycle according to the difference evaluation value; Presetting a first preset difference evaluation value interval, a second preset difference evaluation value interval, a third preset difference evaluation value interval and a fourth preset difference evaluation value interval; When the difference evaluation value is within the first preset difference evaluation value interval, the fourth preset adjustment coefficient z4 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle V0*z4; When the difference evaluation value is in the second preset difference evaluation value interval, the third preset adjustment coefficient z3 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle of V0*z3; When the difference evaluation value is in the third preset difference evaluation value interval, the second preset adjustment coefficient z2 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle of V0*z2; When the difference evaluation value is in the fourth preset difference evaluation value interval, the first preset adjustment coefficient z1 is selected as the first adjustment coefficient and the preset sewage discharge cycle V0 is adjusted to obtain a first adjusted sewage discharge cycle V0*z1; Among them, the first preset difference evaluation value interval < the second preset difference evaluation value interval < 0 < the third preset difference evaluation value < the fourth preset difference evaluation value interval, 0.65 < z1 < z2 < 1 < z3 < z4 < 1.

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6. The method for dynamically adjusting the sewage discharge period of a urea hydrolysis reactor according to claim 5, characterized in that: The first adjustment and discharge cycle is simulated, including: Acquire equipment information and connection information of the urea hydrolysis system, and construct a urea hydrolysis system simulation model of the urea hydrolysis system based on real-time operation data of the urea hydrolysis system and a preset modeling method; Based on the position information of the preset position and the corresponding predicted pollutant accumulation concentration, a corresponding position inside the urea hydrolysis reactor in the urea hydrolysis system simulation model is marked; According to the first functional relationship between the historical characteristic parameters and the historical pollutant accumulation concentration, and the second functional relationship between the historical pollution discharge cycle and the historical operation data in the previous preset pollution discharge cycle operation log, the historical correlation relationship between the historical pollutant accumulation concentration, the historical characteristic parameters and the historical operation data in each historical pollution discharge cycle is obtained; Acquire the dynamic information to be set according to the first adjustment pollutant discharge cycle, and establish a predicted dynamic relationship between the dynamic information to be set and the predicted pollutant accumulation concentration, the real-time characteristic parameters, and the real-time operation data; The predicted dynamic relationship is linked to the urea hydrolysis system simulation model to perform a simulation of the first adjustment and discharge cycle.

7. The method for dynamically adjusting the discharge cycle of a urea hydrolysis reactor according to claim 6, characterized in that: Obtaining the first virtual influence coefficient and the second virtual influence coefficient includes: According to the historical operation log of the urea hydrolysis system, first relevant operation data having a correlation degree with the operation efficiency index greater than a first preset correlation strength is selected, and second relevant operation data having a correlation degree with the ammonia demand index greater than a second preset correlation strength is selected; Acquire simulated first relevant operation data after the first adjustment sewage discharge cycle is simulated, compare the simulated first relevant operation data with a preset standard operation data interval, and generate a first virtual influence coefficient according to the comparison result; Acquire simulated second related operation data after the first adjustment sewage discharge cycle is simulated, compare the simulated second related operation data with a preset standard operation data interval, and generate a second virtual influence coefficient according to the comparison result.

8. The method for dynamically adjusting the sewage discharge period of a urea hydrolysis reactor according to claim 7, characterized in that: And generate the virtual availability of the first adjustment sewage discharge cycle, including: Generate a virtual availability of a first adjustment pollution discharge period according to a virtual decrease rate of the predicted pollutant accumulation concentration at each preset location, a first virtual influence coefficient, and a second virtual influence coefficient; The calculation formula of the virtual availability is: Y = c1*w1+*w2*c2+w3*c3; Among them, Y is the virtual availability, w1 is the virtual decline rate, c1 is the weight coefficient of the virtual decline rate, w2 is the first virtual influence coefficient, c2 is the weight coefficient of the first virtual influence coefficient, w3 is the second virtual influence coefficient, and c3 is the weight coefficient of the second virtual influence coefficient.

9. The method for dynamically adjusting the discharge cycle of a urea hydrolysis reactor according to claim 8, characterized in that: Determining whether to modify the first adjustment discharge cycle according to the virtual availability includes: Pre-set virtual availability threshold; If the virtual availability is less than the virtual availability threshold, a second adjustment coefficient is set according to the availability difference between the virtual availability threshold and the virtual availability, and the first adjustment discharge cycle is corrected to obtain a second adjustment discharge cycle; If the virtual availability is greater than the virtual availability threshold, the first adjustment discharge cycle is not corrected.

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