Method for calculating heat efficiency of waste heat boiler of DMTO device

Abstract

The present application relates to the technical field of chemical production, and discloses a method for accounting for the heat efficiency of a waste heat boiler of a DMTO device, which comprises the following steps: determining the heat released by regenerated flue gas according to the flue gas parameters of the waste heat boiler, then determining the heat carried by catalysts according to the catalyst parameters in the regenerator, determining the dust heat loss according to the flue gas parameters and dust parameters of the waste heat boiler, determining the heat exchange deterioration coefficient according to the pressure drop of the flue gas of the waste heat boiler, determining the stability index according to the fluctuation rate of the operation data within a target time window, and correcting the heat released by the regenerated flue gas by the heat carried by the catalysts, the dust heat loss, the heat exchange deterioration coefficient and the stability index, so as to reduce the influence of the catalysts, the waste heat boiler and the regenerator on heat transfer, and improve the judgment accuracy of the heat efficiency of the waste heat boiler.

Description

Technical Field

[0001] This invention relates to the field of chemical production technology, and in particular to a method for calculating the thermal efficiency of a waste heat boiler in a DMTO unit. Background Technology

[0002] The dimethyl ether and methanol to olefins (DMTO) unit uses dimethyl ether and methanol as feedstock to produce low-carbon olefins such as ethylene and propylene through a catalytic reaction. The DMTO unit operates with a reactor and a regenerator coupled. The catalyst undergoes a catalytic reaction in the reactor, and then the regenerator regenerates the catalyst by burning off the char, restoring its activity and enabling continuous catalyst recycling. During operation, the regenerator continuously generates high-temperature flue gas. To improve energy efficiency, a waste heat boiler is typically installed after the regenerator to recover heat from the high-temperature flue gas and generate high-pressure steam. The thermal efficiency of the waste heat boiler is a key performance indicator.

[0003] However, the thermal efficiency of existing waste heat boilers is usually calculated using the heat balance method, which represents the thermal efficiency of the waste heat boiler by the ratio of heat absorbed by steam to heat released by flue gas. This ignores the influence of catalysts, waste heat boilers, and regenerators on heat transfer, resulting in inaccurate judgment of the thermal efficiency of waste heat boilers. Summary of the Invention

[0004] This invention provides a method for calculating the thermal efficiency of a waste heat boiler in a DMTO (Digital-Depleted Thermal Oxygenation) unit.

[0005] In a first aspect, the present invention provides a method for calculating the thermal efficiency of a waste heat boiler in a DMTO (Digital-to-Oxygen Transformer) device, applied to electronic equipment. The method includes: acquiring operating data of the DMTO device, wherein the DMTO device includes a regenerator and a waste heat boiler; the operating data includes: the inlet regenerated flue gas temperature, inlet regenerated flue gas flow rate, outlet flue gas temperature, outlet flue gas flow rate, outlet dust concentration, outlet dust temperature difference, outlet steam flow rate, outlet steam pressure, outlet steam temperature, and inlet feedwater temperature of the waste heat boiler; and the catalyst circulation rate and catalyst temperature difference corresponding to the regenerator. The heat released by the regenerated flue gas is determined based on the inlet temperature, flow rate, and outlet temperature of the waste heat boiler. The heat carried by the catalyst is determined based on the catalyst circulation rate and catalyst temperature difference. The heat loss due to dust is determined based on the outlet flow rate, dust concentration, and dust temperature difference of the waste heat boiler. The heat input to the boiler is determined based on the heat released by the regenerated flue gas, the heat carried by the catalyst, and the heat loss due to dust. The heat absorbed by the steam is determined based on the outlet steam flow rate, outlet steam pressure, outlet steam temperature, and inlet feedwater temperature of the waste heat boiler. The thermal efficiency of the waste heat boiler is determined based on the boiler input heat and the heat absorbed by the steam.

[0006] In this embodiment of the invention, the heat released by the regenerated flue gas is determined based on the flue gas parameters of the waste heat boiler. Then, the heat carried by the catalyst is determined based on the catalyst parameters in the regenerator. The heat loss of dust is determined based on the flue gas parameters and dust parameters of the waste heat boiler. The heat transfer deterioration coefficient is determined based on the flue gas pressure drop of the waste heat boiler. The stability index is determined based on the fluctuation rate of the operating data within the target time window. The heat released by the regenerated flue gas is corrected by the heat carried by the catalyst, the heat loss of dust, the heat transfer deterioration coefficient, and the stability index, so as to reduce the influence of the catalyst, the waste heat boiler, and the regenerator on heat transfer and improve the accuracy of the judgment of the thermal efficiency of the waste heat boiler.

[0007] In one possible implementation of the first aspect mentioned above, the operating data further includes: the flue gas pressure drop of the waste heat boiler corresponding to the waste heat boiler; determining the boiler input heat based on the heat released by the regenerated flue gas, the heat carried by the catalyst, and the heat loss from dust, including: determining the heat transfer degradation coefficient based on the flue gas pressure drop of the waste heat boiler; and determining the boiler input heat based on the heat released by the regenerated flue gas, the heat carried by the catalyst, the heat loss from dust, and the heat transfer degradation coefficient.

[0008] In one possible implementation of the first aspect above, determining the heat transfer deterioration coefficient based on the waste heat boiler flue gas pressure drop includes: determining the waste heat boiler inlet flue pressure and the waste heat boiler outlet flue pressure; determining the waste heat boiler flue gas pressure drop based on the difference between the waste heat boiler inlet flue pressure and the waste heat boiler outlet flue pressure; obtaining a preset target pressure drop value; and determining the heat transfer deterioration coefficient based on the ratio of the target pressure drop value to the waste heat boiler flue gas pressure drop.

[0009] In one possible implementation of the first aspect above, the boiler input heat is determined based on the heat released by the regenerated flue gas, the heat carried by the catalyst, the heat loss from dust, and the heat transfer deterioration coefficient, including: determining the stability index based on operating data within the target time window; and determining the boiler input heat based on the heat released by the regenerated flue gas, the heat carried by the catalyst, the heat loss from dust, the heat transfer deterioration coefficient, and the stability index.

[0010] In one possible implementation of the first aspect above, the stability index is determined based on the operating data within the target time window, including: determining the temperature fluctuation rate of the regenerated flue gas temperature at the inlet of the waste heat boiler within the target time window, and the first weight corresponding to the temperature fluctuation rate; determining the flow fluctuation rate of the steam flow rate at the outlet of the waste heat boiler within the target time window, and the second weight corresponding to the flow fluctuation rate; determining the circulation fluctuation rate of the catalyst circulation volume within the target time window, and the third weight corresponding to the circulation fluctuation rate; and determining the stability index based on the product of the temperature fluctuation rate and the first weight, the product of the flow fluctuation rate and the second weight, and the product of the circulation fluctuation rate and the third weight.

[0011] In one possible implementation of the first aspect above, determining the heat carried by the catalyst based on the catalyst circulation rate and the catalyst temperature difference includes: determining the temperature of the catalyst to be generated and the temperature of the regenerated catalyst in the regenerator; determining the catalyst temperature difference based on the difference between the temperature of the catalyst to be generated and the temperature of the regenerated catalyst; obtaining a preset average specific heat capacity of the catalyst; and determining the heat carried by the catalyst based on the product of the catalyst circulation rate, the catalyst temperature difference, and the average specific heat capacity of the catalyst.

[0012] In one possible implementation of the first aspect above, determining the dust heat loss based on the waste heat boiler outlet flue gas flow rate, waste heat boiler outlet dust concentration, and waste heat boiler outlet dust temperature difference includes: determining the waste heat boiler outlet dust temperature and a preset ambient reference temperature; determining the waste heat boiler outlet dust temperature difference based on the difference between the waste heat boiler outlet dust temperature and the ambient reference temperature; obtaining a preset dust specific heat capacity; and determining the dust heat loss based on the product of the waste heat boiler outlet flue gas flow rate, waste heat boiler outlet dust concentration, waste heat boiler outlet dust temperature difference, and dust specific heat capacity.

[0013] Secondly, the present invention provides a system for calculating the thermal efficiency of a waste heat boiler in a DMTO (Digital-Depleted Thermal Oxide) unit. The system includes: an acquisition module for acquiring operating data of the DMTO unit, wherein the DMTO unit includes a regenerator and a waste heat boiler, and the operating data includes: the inlet regenerated flue gas temperature, inlet regenerated flue gas flow rate, outlet flue gas temperature, outlet flue gas flow rate, outlet dust concentration, outlet dust temperature difference, outlet steam flow rate, outlet steam pressure, outlet steam temperature, and inlet feedwater temperature of the waste heat boiler; and the catalyst circulation rate and catalyst temperature difference corresponding to the regenerator; and a regenerated flue gas heat release determination module for determining the heat released based on the inlet regenerated flue gas temperature, outlet regenerated flue gas flow rate, outlet dust temperature difference, outlet feedwater temperature, and inlet feedwater temperature of the waste heat boiler; and the catalyst circulation rate and catalyst temperature difference corresponding to the regenerator. The regenerated flue gas flow rate and the waste heat boiler outlet flue gas temperature determine the heat released by the regenerated flue gas; the catalyst-carried heat determination module determines the heat carried by the catalyst based on the catalyst circulation rate and catalyst temperature difference; the dust heat loss determination module determines the dust heat loss based on the waste heat boiler outlet flue gas flow rate, waste heat boiler outlet dust concentration, and waste heat boiler outlet dust temperature difference; the boiler input heat determination module determines the boiler input heat based on the heat released by the regenerated flue gas, the catalyst-carried heat, and the dust heat loss; the steam absorption heat determination module determines the steam absorption heat based on the waste heat boiler outlet steam flow rate, waste heat boiler outlet steam pressure, waste heat boiler outlet steam temperature, and waste heat boiler inlet feedwater temperature; and the thermal efficiency determination module determines the waste heat boiler thermal efficiency based on the boiler input heat and steam absorption heat.

[0014] Thirdly, embodiments of the present invention provide a computer-readable storage medium storing instructions that, when executed on an electronic device, cause the electronic device to implement any of the methods for calculating the thermal efficiency of a waste heat boiler in a DMTO device provided by the first aspect and various possible implementations of the first aspect.

[0015] Fourthly, embodiments of the present invention provide an electronic device comprising: a memory for storing instructions executed by one or more processors of the electronic device; and a processor, one of the processors of the electronic device, for executing the instructions stored in the memory to implement any of the methods for calculating the thermal efficiency of a waste heat boiler in a DMTO device provided by the first aspect and various possible implementations of the first aspect.

[0016] Fifthly, embodiments of the present invention provide a program product including instructions that, when executed by an electronic device, enable the electronic device to implement any of the methods for calculating the thermal efficiency of a DMTO device waste heat boiler provided by the first aspect and various possible implementations of the first aspect. Attached Figure Description

[0017] Figure 1 According to some embodiments of the present invention, a schematic flowchart of a method for calculating the thermal efficiency of a waste heat boiler in a DMTO unit is shown. Figure 2 According to some embodiments of the present invention, a schematic diagram of a module example of an apparatus for calculating the thermal efficiency of a waste heat boiler in a DMTO unit is shown. Figure 3 According to some embodiments of the present invention, an example schematic diagram of an electronic device is shown. Detailed Implementation

[0018] The illustrative embodiments of the present invention include, but are not limited to, a method for calculating the thermal efficiency of a waste heat boiler in a DMTO unit.

[0019] The following description is intended to disclose the present invention and enable those skilled in the art to implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art. The basic principles of the invention defined in the following description can be applied to other embodiments, modifications, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the invention.

[0020] As mentioned earlier, the thermal efficiency of existing waste heat boilers is usually calculated using the heat balance method, which represents the thermal efficiency of the waste heat boiler by the ratio of heat absorbed by steam to heat released by flue gas. This ignores the influence of catalysts, waste heat boilers, and regenerators on heat transfer, leading to inaccurate judgment of the thermal efficiency of waste heat boilers.

[0021] To address this, the present invention provides a method for calculating the thermal efficiency of a waste heat boiler in a DMTO (Digital-Depleted Thermal Oxygenation) unit. The method involves determining the heat released by the regenerated flue gas based on the flue gas parameters of the waste heat boiler, then determining the heat carried by the catalyst based on the catalyst parameters in the regenerator, determining the dust heat loss based on the flue gas and dust parameters of the waste heat boiler, determining the heat transfer degradation coefficient based on the flue gas pressure drop of the waste heat boiler, and determining the stability index based on the fluctuation rate of the operating data within a target time window. By adjusting the heat released by the regenerated flue gas using the catalyst heat carry-on, dust heat loss, heat transfer degradation coefficient, and stability index, the method aims to reduce the impact of the catalyst, waste heat boiler, and regenerator on heat transfer and improve the accuracy of determining the thermal efficiency of the waste heat boiler.

[0022] The following is in conjunction with the appendix Figures 1 to 3 The technical solution of the present invention will be described.

[0023] Figure 1 According to some embodiments of the present invention, a flowchart of a method for calculating the thermal efficiency of a waste heat boiler in a DMTO (Digital-to-Oxygen Transmission) unit is shown. It can be understood that... Figure 1 The processes shown are all executed by electronic devices. For the sake of simplicity, the following description will be further elaborated upon. Figure 1The execution entity will not be described again in the illustrated process. For example, as shown... Figure 1 As shown, the method for calculating the thermal efficiency of the waste heat boiler in a DMTO unit includes, but is not limited to, the following process: S11: Obtain the operating data of the DMTO device.

[0024] In some embodiments, a DMTO unit includes a regenerator and a waste heat boiler. It is understood that the DMTO unit operates in a reactor-regenerator coupling configuration, where the catalyst undergoes a catalytic reaction in the reactor, and then the regenerator regenerates the catalyst after the catalytic reaction by burning off the coke to restore its activity, thus achieving continuous catalyst recycling. During the operation of the DMTO unit, the regenerator continuously generates high-temperature flue gas. To improve energy efficiency, a waste heat boiler is typically installed after the regenerator to recover heat from the high-temperature flue gas generated by the regenerator and produce high-pressure steam. Therefore, the regenerator and the waste heat boiler are connected, and the inlet of the waste heat boiler is connected to the outlet of the regenerator.

[0025] In some embodiments, the electronic device communicates with the distributed control system (DCS) of the DMTO device to acquire operational data. Exemplarily, the operational data includes: the inlet regenerated flue gas temperature, inlet regenerated flue gas flow rate, outlet flue gas temperature, outlet flue gas flow rate, outlet dust concentration, outlet dust temperature difference, outlet steam flow rate, outlet steam pressure, outlet steam temperature, and inlet feedwater temperature of the waste heat boiler; and the catalyst circulation rate and catalyst temperature difference of the regenerator.

[0026] In some embodiments, a flue gas temperature transmitter and a flue gas flow meter are installed at the inlet flue of the waste heat boiler. The flue gas temperature transmitter is used to measure the temperature of the regenerated flue gas entering the waste heat boiler in real time and send the corresponding temperature data to the DCS system. The flue gas flow meter is used to measure the flow rate of the regenerated flue gas entering the waste heat boiler in real time and send the corresponding flow rate data to the DCS system. Electronic equipment reads the temperature and flow rate of the regenerated flue gas from the DCS system via an industrial Ethernet or OPC communication interface.

[0027] In some embodiments, a flue gas temperature transmitter, a flue gas flow meter, and a dust concentration analyzer are installed at the outlet flue of the waste heat boiler. The flue gas temperature transmitter measures the temperature of the flue gas after heat exchange to obtain the outlet flue gas temperature of the waste heat boiler; the flue gas flow meter measures the flow rate of the flue gas at the outlet of the waste heat boiler; and the dust concentration analyzer measures the concentration of particulate matter in the flue gas to obtain the dust concentration at the outlet of the waste heat boiler. The flue gas temperature transmitter, flue gas flow meter, and dust concentration analyzer upload the measured data to the DCS system, and electronic equipment reads the corresponding data from the DCS system, such as the outlet flue gas temperature, flow rate, and dust concentration of the waste heat boiler.

[0028] In some embodiments, a dust temperature measuring device is installed in the flue gas outlet of the waste heat boiler. The dust temperature at the outlet of the waste heat boiler is measured by the dust temperature measuring device. After the dust temperature measuring device uploads the measured data to the DCS system, the electronic equipment reads the corresponding data from the DCS system, such as the dust temperature at the outlet of the waste heat boiler. Then, the electronic equipment determines the dust temperature difference at the outlet of the waste heat boiler by the temperature difference between the dust temperature at the outlet of the waste heat boiler and the preset ambient reference temperature.

[0029] In some embodiments, a steam flow meter, a temperature gauge, and a pressure transmitter are installed at the steam outlet main pipe of the waste heat boiler. The steam flow meter measures the steam flow rate generated by the waste heat boiler to obtain the waste heat boiler outlet steam flow rate; the temperature gauge measures the steam temperature to obtain the waste heat boiler outlet steam temperature; and the pressure transmitter measures the steam pressure to obtain the waste heat boiler outlet steam pressure. A feedwater temperature transmitter is installed on the waste heat boiler feedwater inlet pipeline to measure the feedwater temperature entering the waste heat boiler to obtain the waste heat boiler inlet feedwater temperature. The steam flow meter, temperature gauge, pressure transmitter, and feedwater flow meter upload the measured data to the DCS system. Electronic equipment reads the corresponding data from the DCS system, such as the waste heat boiler outlet steam flow rate, waste heat boiler outlet steam pressure, waste heat boiler outlet steam temperature, and waste heat boiler inlet feedwater temperature.

[0030] In some embodiments, a catalyst circulation rate measuring device is installed on the catalyst circulation line of the regenerator to measure the mass flow rate of the circulating catalyst per unit time, thereby obtaining the catalyst circulation rate. A regenerated catalyst temperature measuring device is installed in the dense phase bed region of the regenerator to obtain the regenerated catalyst temperature; a dormant catalyst temperature measuring device is installed on the dormant catalyst return line to obtain the dormant catalyst temperature. The catalyst circulation rate measuring device, the regenerated catalyst temperature measuring device, and the dormant catalyst temperature measuring device upload the measured data to the DCS system. Electronic equipment reads the corresponding data from the DCS system, such as the catalyst circulation rate, the regenerated catalyst temperature, and the dormant catalyst temperature. Subsequently, the electronic equipment determines the catalyst temperature difference based on the temperature difference between the regenerated catalyst temperature and the dormant catalyst temperature.

[0031] S12: Determine the heat released by the regenerated flue gas based on the inlet temperature of the waste heat boiler, the inlet flow rate of the regenerated flue gas, and the outlet temperature of the waste heat boiler.

[0032] In some embodiments, the electronic device acquires a preset average specific heat capacity of the flue gas, determines the temperature difference between the inlet and outlet flue gas of the waste heat boiler based on the inlet regenerated flue gas temperature and the outlet flue gas temperature of the waste heat boiler, and then determines the heat released by the regenerated flue gas based on the product of the average specific heat capacity of the flue gas, the inlet regenerated flue gas flow rate of the waste heat boiler, and the temperature difference between the inlet and outlet flue gas of the waste heat boiler. For example, see formula (1): Qg=Fg,in×Cpg×(Tg,in-Tg,out) (Formula 1) As shown in formula (1), Qg represents the heat released by the regenerated flue gas, Fg,in represents the flow rate of the regenerated flue gas at the inlet of the waste heat boiler, Cpg represents the preset average specific heat capacity of the flue gas, Tg,in represents the temperature of the regenerated flue gas at the inlet of the waste heat boiler, and Tg,out represents the temperature of the flue gas at the outlet of the waste heat boiler. For example, the flow rate of the regenerated flue gas at the inlet of the waste heat boiler is 420,000 Nm³. 3 With a preset average specific heat capacity of flue gas of 1.15 kJ / (Nm3⋅℃), an inlet temperature of 720℃ for the regenerated flue gas from the waste heat boiler, and an outlet temperature of 265℃ for the waste heat boiler, the heat released by the regenerated flue gas is approximately 61.05 MW.

[0033] S13: Determine the heat carried by the catalyst based on the catalyst circulation rate and catalyst temperature difference.

[0034] In some embodiments, the electronic device reads the temperature of the catalyst to be generated and the temperature of the catalyst to be regenerated in the regenerator from the DCS system, and determines the catalyst temperature difference based on the difference between the temperatures of the catalyst to be generated and the catalyst to be regenerated; then the electronic device obtains a preset average specific heat capacity of the catalyst, and determines the heat carried by the catalyst based on the product of the catalyst circulation rate, the catalyst temperature difference, and the average specific heat capacity of the catalyst. For example, see formula (2): Qc=Fc×Cpc×ΔTc (Formula 2) As shown in formula (2), Qc represents the heat carried by the catalyst; Fc represents the catalyst circulation rate, which characterizes the total mass of catalyst participating in the circulation per unit time. The larger the catalyst circulation rate, the more catalyst enters the waste heat boiler area per unit time, and therefore the more heat it can carry; Cpc represents the preset average specific heat capacity of the catalyst, which characterizes the catalyst's ability to store heat. When the catalyst composition changes, its heat storage capacity will also change. Therefore, the specific heat capacity parameter is used to describe the thermal characteristics of the catalyst; ΔTc represents the catalyst temperature difference, which represents the temperature change before and after the catalyst releases heat. The larger the temperature difference, the more heat is released. For example, if the catalyst circulation rate is 118000 kg / h, the preset average specific heat capacity of the catalyst is 1.02 kJ / (kg·℃), and the catalyst temperature difference is 120℃, then the catalyst carries approximately 4.0 MW of heat.

[0035] It is understandable that the catalyst in the regenerator is typically at a high temperature after coking regeneration, such as above 650℃. During catalyst circulation, a large amount of heat is stored inside the catalyst particles in the form of sensible heat. When some fine catalyst particles enter the waste heat boiler, the sensible heat they carry will continue to participate in the heat exchange process. Therefore, the actual heat entering the waste heat boiler should include at least the heat released by the regenerated flue gas and the heat carried by the catalyst. Incorporating the heat carried by the catalyst into the thermal efficiency calculation can significantly improve the accuracy of the heat input calculation.

[0036] S14: Determine the dust heat loss based on the flue gas flow rate at the waste heat boiler outlet, the dust concentration at the waste heat boiler outlet, and the dust temperature difference at the waste heat boiler outlet.

[0037] In some embodiments, the electronic device reads the dust temperature at the outlet of the waste heat boiler from the DCS system and determines the dust temperature difference at the outlet of the waste heat boiler based on the difference between the dust temperature at the outlet of the waste heat boiler and a preset ambient reference temperature; subsequently, the electronic device obtains a preset dust specific heat capacity and determines the dust heat loss based on the product of the flue gas flow rate at the outlet of the waste heat boiler, the dust concentration at the outlet of the waste heat boiler, the dust temperature difference at the outlet of the waste heat boiler, and the dust specific heat capacity. For example, see formula (3): Qd=Cd×Fg,out×Cpd×(Td-Ta) (Formula 3) As shown in formula (3), Qd represents the dust heat loss, Cd represents the dust concentration at the outlet of the waste heat boiler, Fg,out represents the flue gas flow rate at the outlet of the waste heat boiler, Cpd represents the preset dust specific heat capacity, Td represents the dust temperature at the outlet of the waste heat boiler, and Ta represents the ambient reference temperature. For example, the dust concentration at the outlet of the waste heat boiler is 42 mg / Nm³. 3 The flue gas flow rate at the outlet of the waste heat boiler is 420,000 Nm³. 3The preset dust specific heat capacity is 0.95 kJ / (kg·℃), the waste heat boiler outlet dust temperature is 265℃, the ambient reference temperature is 25℃, and the dust heat loss is approximately 0.001MW.

[0038] It is understandable that the large amount of catalyst dust entrained in the regenerated flue gas will also affect the heat balance. This is because the dust particles remain at a relatively high temperature when they leave the waste heat boiler, and the heat they carry is not absorbed by the steam but is directly discharged from the system. Therefore, the actual heat entering the waste heat boiler should at least deduct the heat loss due to dust to avoid artificially inflated thermal efficiency. Although this portion of heat accounts for a small proportion of the total heat, it can reflect the impact of the heat entrained by dust on the heat balance.

[0039] S15: Determine the boiler input heat based on the heat released by the regenerated flue gas, the heat carried by the catalyst, and the heat loss from dust.

[0040] In some embodiments, the electronic device can determine the boiler input heat by adding the heat released by the regenerated flue gas and the heat carried by the catalyst, and then subtracting the heat loss from the dust. For example, if the heat released by the regenerated flue gas is approximately 61.05 MW, the heat carried by the catalyst is approximately 4.0 MW, and the heat loss from the dust is approximately 0.001 MW, then the boiler input heat is approximately 65.049 MW.

[0041] In other embodiments, ash accumulation is prone to occur on the surface of the heat exchange tubes in the waste heat boiler. The ash layer increases thermal resistance, making it difficult for heat in the flue gas to be transferred to the interior of the heat exchange tubes. Therefore, this invention further incorporates the influence of ash accumulation on the surface of the heat exchange tubes when calculating the boiler input heat. For example, the electronic equipment determines the heat transfer degradation coefficient based on the flue gas pressure drop of the waste heat boiler, and determines the boiler input heat based on the heat released by the regenerated flue gas, the heat carried by the catalyst, the heat loss from dust, and the heat transfer degradation coefficient.

[0042] For example, pressure measuring devices are installed at the inlet and outlet flues of the waste heat boiler to measure the inlet and outlet flue pressures, respectively. The measured data is then uploaded to the DCS system, and electronic equipment reads the corresponding data, such as the inlet and outlet flue pressures, from the DCS system. The electronic equipment then determines the flue gas pressure drop of the waste heat boiler based on the difference between the inlet and outlet flue pressures. It can be understood that changes in pressure drop essentially reflect changes in flue gas flow resistance. When ash accumulation on the heat exchanger tube surface increases, the flue gas flow cross-section decreases, and the pressure drop increases. Therefore, changes in pressure drop can indirectly reflect changes in heat exchange capacity.

[0043] Furthermore, the electronic device acquires a preset target pressure drop value, which represents the difference between the inlet flue pressure and the outlet flue pressure of the waste heat boiler when the waste heat boiler is in a clean state. Subsequently, the electronic device determines the heat transfer degradation coefficient based on the ratio of the target pressure drop value to the waste heat boiler flue gas pressure drop. For example, if the target pressure drop value is 6.0 kPa and the waste heat boiler flue gas pressure drop is 8.6 kPa, then the heat transfer degradation coefficient is approximately 1.433.

[0044] For example, the electronic equipment can determine the boiler input heat by adding the heat released by the regenerated flue gas and the heat carried by the catalyst, subtracting the heat loss from the dust, and finally multiplying by the thermal degradation coefficient. For instance, if the heat released by the regenerated flue gas is approximately 61.05 MW, the heat carried by the catalyst is approximately 4.0 MW, the heat loss from the dust is approximately 0.001 MW, and the thermal degradation coefficient is approximately 1.433, then the boiler input heat is approximately 93.215 MW.

[0045] In other embodiments, the DMTO unit is a dynamic production system. For example, changes in methanol feed, regeneration air volume, and catalyst circulation volume can all cause fluctuations in the heat transfer process. If instantaneous data is used directly to calculate the thermal efficiency, the results may show significant jumps. Therefore, this invention further incorporates the influence of unit operation variations when calculating the boiler input heat. For example, the electronic equipment determines a stability index based on operating data within a target time window, and then determines the boiler input heat based on the heat released by the regeneration flue gas, the heat carried by the catalyst, the heat loss from dust, the heat transfer deterioration coefficient, and the stability index.

[0046] For example, the electronic device determines the temperature fluctuation rate of the regenerated flue gas temperature at the inlet of the waste heat boiler within a target time window, and the first weight corresponding to the temperature fluctuation rate; determines the flow rate fluctuation rate of the steam flow rate at the outlet of the waste heat boiler within the target time window, and the second weight corresponding to the flow rate fluctuation rate; and determines the circulation rate fluctuation rate of the catalyst circulation within the target time window, and the third weight corresponding to the circulation rate fluctuation rate. The electronic device then determines a stability index based on the product of the temperature fluctuation rate and the first weight, the product of the flow rate fluctuation rate and the second weight, and the product of the circulation rate fluctuation rate and the third weight.

[0047] In some embodiments, the temperature fluctuation rate of the waste heat boiler inlet regenerated flue gas temperature within the target time window can be determined by the ratio of the standard deviation to the average value of multiple waste heat boiler inlet regenerated flue gas temperatures at a preset time interval (e.g., 1 second) within the target time window (e.g., 30 minutes); the flow rate fluctuation rate and circulation rate fluctuation rate are similar and will not be elaborated here.

[0048] In some embodiments, the first weight, the second weight, and the third weight can be preset by the user, for example, 0.4, 0.4, and 0.2 respectively, without any specific limitation. For example, see formula (4): SI=1-(w1×RT+w2×RS+w3×RC) (Formula 4) As shown in formula (4), SI represents the stability index, RT represents the temperature fluctuation rate, w1 represents the first weight, RS represents the flow fluctuation rate, w2 represents the second weight, RC represents the circulation fluctuation rate, and w3 represents the third weight. For example, if the temperature fluctuation rate is 2.5%, the flow fluctuation rate is 1.8%, the circulation fluctuation rate is 2.2%, and the first, second, and third weights are 0.4, 0.4, and 0.2 respectively, then the stability index is approximately 0.978.

[0049] For example, the electronic equipment can determine the boiler input heat by adding the heat released by the regenerated flue gas and the heat carried by the catalyst, subtracting the dust heat loss, and finally multiplying by the thermal deterioration coefficient and the stability index. For instance, if the heat released by the regenerated flue gas is approximately 61.05 MW, the heat carried by the catalyst is approximately 4.0 MW, the dust heat loss is approximately 0.001 MW, the thermal deterioration coefficient is approximately 1.433, and the stability index is approximately 0.978, then the boiler input heat is approximately 91.164 MW.

[0050] S16: Determine the heat absorbed by the steam based on the steam flow rate, steam pressure, steam temperature, and feedwater temperature at the outlet of the waste heat boiler.

[0051] In some embodiments, see formula (5): Qout = Fs × [H(Ps,Ts) - H(Tw)] (Formula 5) As shown in formula (5), Qout represents the heat absorbed by the steam, Fs represents the steam flow rate at the outlet of the waste heat boiler, Ps represents the steam pressure at the outlet of the waste heat boiler, Ts represents the steam temperature at the outlet of the waste heat boiler, H(Ps, Ts) represents the steam enthalpy obtained from the steam pressure and temperature at the outlet of the waste heat boiler, Tw represents the feedwater temperature at the inlet of the waste heat boiler, and H(Tw) represents the feedwater enthalpy obtained from the feedwater temperature at the inlet of the waste heat boiler. For example, the heat absorbed by the steam is approximately 79.632 MW.

[0052] S17: Determine the thermal efficiency of the waste heat boiler based on the heat input to the boiler and the heat absorbed by the steam.

[0053] In some embodiments, the electronic device determines the waste heat boiler thermal efficiency based on the ratio of heat absorbed by the steam to heat input to the boiler. For example, if the boiler heat input is approximately 91.164 MW and the steam heat absorption is approximately 79.632 MW, then the waste heat boiler thermal efficiency is 87.35%.

[0054] It is understood that this invention corrects the heat released by regenerated flue gas by considering the heat carried by the catalyst, the heat loss from dust, the heat transfer deterioration coefficient, and the stability index, so as to reduce the impact of the catalyst, the waste heat boiler, and the regenerator on heat transfer and improve the accuracy of judging the thermal efficiency of the waste heat boiler.

[0055] In some embodiments, this application also proposes a system for calculating the thermal efficiency of a waste heat boiler in a DMTO (Digital-Depleted Thermal Oxygenation) unit. Exemplarily, Figure 2 According to some embodiments of the present invention, a block diagram of a system for calculating the thermal efficiency of a waste heat boiler in a DMTO (Digital-Depleted Thermal Oxygenation) unit is shown. Figure 2 As shown, the system 200 for calculating the thermal efficiency of the waste heat boiler in the DMTO unit includes, but is not limited to: acquisition module 21, regenerated flue gas heat release determination module 22, catalyst heat carry-over determination module 23, dust heat loss determination module 24, boiler input heat determination module 25, steam absorption heat determination module 26, and thermal efficiency determination module 27.

[0056] For example, the acquisition module 21 is used to acquire the operating data of the DMTO device, wherein the DMTO device includes a regenerator and a waste heat boiler, and the operating data includes: the waste heat boiler inlet regenerated flue gas temperature, waste heat boiler inlet regenerated flue gas flow rate, waste heat boiler outlet flue gas temperature, waste heat boiler outlet flue gas flow rate, waste heat boiler outlet dust concentration, waste heat boiler outlet dust temperature difference, waste heat boiler outlet steam flow rate, waste heat boiler outlet steam pressure, waste heat boiler outlet steam temperature, and waste heat boiler inlet feedwater temperature, and the catalyst circulation rate and catalyst temperature difference corresponding to the regenerator; For example, the regenerated flue gas heat release determination module 22 is used to determine the regenerated flue gas heat release based on the regenerated flue gas temperature at the inlet of the waste heat boiler, the regenerated flue gas flow rate at the inlet of the waste heat boiler, and the waste heat boiler outlet flue gas temperature. For example, the catalyst carrying heat determination module 23 is used to determine the catalyst carrying heat based on the catalyst circulation rate and the catalyst temperature difference; For example, the dust heat loss determination module 24 is used to determine the dust heat loss based on the flue gas flow rate at the outlet of the waste heat boiler, the dust concentration at the outlet of the waste heat boiler, and the dust temperature difference at the outlet of the waste heat boiler. For example, the boiler input heat determination module 25 determines the boiler input heat based on the heat released by the regenerated flue gas, the heat carried by the catalyst, and the heat loss from the dust. For example, the steam absorption heat determination module 26 determines the steam absorption heat based on the steam flow rate at the outlet of the waste heat boiler, the steam pressure at the outlet of the waste heat boiler, the steam temperature at the outlet of the waste heat boiler, and the feedwater temperature at the inlet of the waste heat boiler. For example, the thermal efficiency determination module 27 is used to determine the thermal efficiency of the waste heat boiler based on the heat input to the boiler and the heat absorbed by the steam.

[0057] Understandable. Figure 2 For a detailed description of the functions and roles of the system modules shown, please refer to the aforementioned Figure 1 The process descriptions of S01 to S07 shown are not repeated here.

[0058] It needs to be explained that, Figure 2 This is merely one possible implementation of the present invention. In actual applications, the system 200 for calculating the thermal efficiency of the waste heat boiler of the DMTO device may include more or fewer modules, which will not be elaborated here.

[0059] Figure 3 According to some embodiments of the present invention, a schematic diagram of the structure of an electronic device 100 is shown. For example... Figure 3 As shown, the electronic device 100 includes a processor 101, a communication interface 103, and a memory 102. The processor 101, communication interface 103, and memory 102 can be interconnected via an internal bus 104, or they can communicate via wireless transmission or other means. This embodiment of the invention uses the connection via bus 104 as an example. Bus 104 can be a peripheral component interconnect express (PCIe) bus, an extended industry standard architecture (EISA) bus, a unified bus (Ubus or UB), a compute express link (CXL), a cache coherent interconnect for accelerators (CCIX), etc. Bus 104 can be divided into address bus, data bus, control bus, etc. In addition to the data bus, bus 104 can also include a power bus, a control bus, and a status signal bus. For clarity, all buses are labeled as bus 104 in the figure.

[0060] Processor 101 may consist of at least one general-purpose processor, such as a central processing unit (CPU), or a combination of a CPU and a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The PLD may be a complex programmable logic device (CPLD), a field-programmable gate array (FPGA), a generic array logic (GAL), or any combination thereof. Processor 101 executes various types of digital storage instructions, such as software or firmware programs stored in memory 102, enabling electronic device 100 to provide a variety of services.

[0061] Memory 102 may include volatile memory, such as random access memory (RAM); memory 102 may also include non-volatile memory, such as read-only memory (ROM), flash memory, hard disk drive (HDD), or solid-state drive (SSD); memory 102 may also include combinations of the above types.

[0062] The communication interface 103 can be a wired interface (e.g., an Ethernet interface), an internal interface (e.g., a PCIe bus interface), a wired interface (e.g., an Ethernet interface), or a wireless interface (e.g., a cellular network interface or a wireless LAN interface), for communicating with other devices or modules.

[0063] It needs to be explained that, Figure 3 This is merely one possible implementation of an embodiment of the present invention. In actual applications, the electronic device 100 may include more or fewer components, which will not be elaborated here.

[0064] In some embodiments, the present invention also provides a computer-readable medium storing program code that, when run on a computer, causes the computer to perform the methods described in the above aspects.

[0065] In some embodiments, the present invention also provides a computer program product comprising: computer program code that, when run on a computer, causes the computer to perform the methods described above.

[0066] In the accompanying drawings, some structural or methodological features may be shown in a specific arrangement and / or order. However, it should be understood that such a specific arrangement and / or order may not be necessary. Rather, in some embodiments, these features may be arranged in a manner and / or order different from that shown in the illustrative drawings. Furthermore, the inclusion of structural or methodological features in a particular figure does not imply that such features are required in all embodiments, and in some embodiments, these features may be omitted or may be combined with other features.

[0067] It should be noted that the units / modules mentioned in the various device embodiments of the present invention are all logical units / modules. Physically, a logical unit / module can be a physical unit / module, a part of a physical unit / module, or a combination of multiple physical units / modules. The physical implementation of these logical units / modules themselves is not the most important factor; the combination of functions implemented by these logical units / modules is the key to solving the technical problem proposed by the present invention. Furthermore, to highlight the innovative aspects of the present invention, the above-described device embodiments of the present invention have not introduced units / modules that are not closely related to solving the technical problem proposed by the present invention. This does not mean that the above-described device embodiments do not contain other units / modules.

[0068] It should be noted that in the examples and description of this patent, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0069] Although the invention has been illustrated and described with reference to certain preferred embodiments thereof, those skilled in the art will understand that various changes in form and detail may be made therein without departing from the scope of the invention.

Claims

1. A method for calculating the thermal efficiency of a waste heat boiler in a DMTO (Digital-to-Energy) unit, applied to electronic equipment, characterized in that... The method includes: Obtain operating data of the DMTO device, wherein the DMTO device includes a regenerator and a waste heat boiler, and the operating data includes: the inlet regenerated flue gas temperature, the inlet regenerated flue gas flow rate, the outlet flue gas temperature, the outlet flue gas flow rate, the outlet dust concentration, the outlet dust temperature difference, the outlet steam flow rate, the outlet steam pressure, the outlet steam temperature, and the inlet feedwater temperature of the waste heat boiler; and the catalyst circulation rate and catalyst temperature difference corresponding to the regenerator. The heat released by the regenerated flue gas is determined based on the inlet temperature of the waste heat boiler, the inlet flow rate of the regenerated flue gas, and the outlet temperature of the waste heat boiler. The heat carried by the catalyst is determined based on the catalyst circulation rate and the catalyst temperature difference. Dust heat loss is determined based on the flue gas flow rate at the outlet of the waste heat boiler, the dust concentration at the outlet of the waste heat boiler, and the dust temperature difference at the outlet of the waste heat boiler. The boiler input heat is determined based on the heat released by the regenerated flue gas, the heat carried by the catalyst, and the heat loss from the dust. The heat absorbed by the steam is determined based on the steam flow rate at the outlet of the waste heat boiler, the steam pressure at the outlet of the waste heat boiler, the steam temperature at the outlet of the waste heat boiler, and the feedwater temperature at the inlet of the waste heat boiler. The thermal efficiency of the waste heat boiler is determined based on the heat input to the boiler and the heat absorbed by the steam.

2. The method according to claim 1, characterized in that, The operating data also includes: the flue gas pressure drop of the waste heat boiler corresponding to the waste heat boiler; The determination of boiler input heat based on the heat released by the regenerated flue gas, the heat carried by the catalyst, and the heat loss from dust includes: The heat transfer degradation coefficient is determined based on the pressure drop of the waste heat boiler flue gas. The boiler input heat is determined based on the heat released by the regenerated flue gas, the heat carried by the catalyst, the heat loss from the dust, and the heat exchange deterioration coefficient.

3. The method according to claim 2, characterized in that, The determination of the heat transfer degradation coefficient based on the flue gas pressure drop of the waste heat boiler includes: Determine the inlet flue pressure and outlet flue pressure of the waste heat boiler; The pressure drop of the waste heat boiler flue gas is determined based on the difference between the inlet flue pressure and the outlet flue pressure of the waste heat boiler. Obtain the preset target pressure drop value; The heat exchange deterioration coefficient is determined based on the ratio of the target pressure drop value to the flue gas pressure drop of the waste heat boiler.

4. The method according to claim 2, characterized in that, The step of determining the boiler input heat based on the heat released by the regenerated flue gas, the heat carried by the catalyst, the heat loss from dust, and the heat transfer deterioration coefficient includes: The stability index is determined based on the operational data within the target time window. The boiler input heat is determined based on the heat released by the regenerated flue gas, the heat carried by the catalyst, the heat loss from dust, the heat exchange deterioration coefficient, and the stability index.

5. The method according to claim 4, characterized in that, The step of determining the stability index based on the operational data within the target time window includes: Determine the temperature fluctuation rate of the regenerated flue gas at the inlet of the waste heat boiler within the target time window, and the first weight corresponding to the temperature fluctuation rate; Determine the flow rate fluctuation of the waste heat boiler outlet steam flow rate within the target time window, and the second weight corresponding to the flow rate fluctuation; Determine the volatility of the catalyst circulation volume within the target time window, and the third weight corresponding to the volatility of the circulation volume; The stability index is determined based on the product of the temperature volatility and the first weight, the product of the flow volatility and the second weight, and the product of the circulation volatility and the third weight.

6. The method according to any one of claims 1 to 5, characterized in that, The step of determining the heat carried by the catalyst based on the catalyst circulation rate and the catalyst temperature difference includes: Determine the temperature of the catalyst to be generated and the temperature of the catalyst to be regenerated in the regenerator; The catalyst temperature difference is determined based on the difference between the temperature of the catalyst to be generated and the temperature of the regenerated catalyst. Obtain the preset average specific heat capacity of the catalyst; The heat carried by the catalyst is determined by the product of the catalyst circulation rate, the catalyst temperature difference, and the catalyst average specific heat capacity.

7. The method according to any one of claims 1 to 5, characterized in that, The determination of dust heat loss based on the flue gas flow rate at the outlet of the waste heat boiler, the dust concentration at the outlet of the waste heat boiler, and the dust temperature difference at the outlet of the waste heat boiler includes: Determine the dust temperature at the outlet of the waste heat boiler and the preset ambient reference temperature; The waste heat boiler outlet dust temperature difference is determined based on the difference between the outlet dust temperature of the waste heat boiler and the ambient reference temperature. Obtain the preset specific heat capacity of the dust; The dust heat loss is determined by multiplying the flue gas flow rate at the outlet of the waste heat boiler, the dust concentration at the outlet of the waste heat boiler, the dust temperature difference at the outlet of the waste heat boiler, and the specific heat capacity of the dust.

8. A system for calculating the thermal efficiency of a waste heat boiler in a DMTO (Digital-to-Oxygen Transmission) unit, characterized in that, The system includes: The acquisition module is used to acquire the operating data of the DMTO device, wherein the DMTO device includes a regenerator and a waste heat boiler, and the operating data includes: the inlet regenerated flue gas temperature, the inlet regenerated flue gas flow rate, the outlet flue gas temperature, the outlet flue gas flow rate, the outlet dust concentration, the outlet dust temperature difference, the outlet steam flow rate, the outlet steam pressure, the outlet steam temperature, and the inlet feedwater temperature of the waste heat boiler; and the catalyst circulation rate and catalyst temperature difference corresponding to the regenerator. The module for determining the heat released by regenerated flue gas is used to determine the heat released by regenerated flue gas based on the temperature of the regenerated flue gas at the inlet of the waste heat boiler, the flow rate of the regenerated flue gas at the inlet of the waste heat boiler, and the temperature of the flue gas at the outlet of the waste heat boiler. A catalyst heat carrying capacity determination module is used to determine the catalyst heat carrying capacity based on the catalyst circulation rate and the catalyst temperature difference. The dust heat loss determination module is used to determine the dust heat loss based on the flue gas flow rate at the outlet of the waste heat boiler, the dust concentration at the outlet of the waste heat boiler, and the dust temperature difference at the outlet of the waste heat boiler. The boiler input heat determination module determines the boiler input heat based on the heat released by the regenerated flue gas, the heat carried by the catalyst, and the heat loss from the dust. The steam heat absorption determination module determines the steam heat absorption based on the waste heat boiler outlet steam flow rate, the waste heat boiler outlet steam pressure, the waste heat boiler outlet steam temperature, and the waste heat boiler inlet feedwater temperature. The thermal efficiency determination module is used to determine the thermal efficiency of the waste heat boiler based on the heat input to the boiler and the heat absorbed by the steam.

9. A computer-readable storage medium, characterized in that, The readable storage medium stores instructions that, when executed on an electronic device, cause the electronic device to perform the method of any one of claims 1 to 7.

10. An electronic device, characterized in that, include: Memory is used to store instructions executed by one or more processors of an electronic device; And a processor, one of the processors of the electronic device, for executing instructions stored in the memory to implement the method of any one of claims 1 to 7.

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