Heat exchange waste gas recovery method and system, intelligent terminal and storage medium

Abstract

The invention relates to a heat exchange waste gas recycling method and system, an intelligent terminal and a storage medium, and relates to the field of energy conservation and emission reduction, the method comprises the steps that after heat exchange waste gas passes through a heat exchange device, the heat exchange waste gas is introduced into a recycling device, the recycling device comprises a steam inlet pipeline, a steam exhaust pipeline and a water drainage pipeline, and a control valve is arranged on the water drainage pipeline; the recovery device is used for separating gas and liquid in the heat exchange waste gas to obtain recovered waste gas and recovered wastewater, the recovered waste gas leaves the recovery device from the steam exhaust pipeline, and the recovered wastewater leaves the recovery device from the drainage pipeline; acquiring a real-time liquid level in the recovery device; calculating a liquid level difference value between the real-time liquid level and a first preset liquid level; and the valve opening degree of the control valve is adjusted according to the liquid level difference value, so that the real-time liquid level is located between the first preset liquid level and a second preset liquid level, and the second preset liquid level is larger than the first preset liquid level. The recovery device has the effect of ensuring the liquid level balance in the recovery device.

Description

Technical Field

[0001] The present application relates to the field of energy conservation and emission reduction, and in particular to a method, system, intelligent terminal and storage medium for recovering heat exchange waste gas. Background Art

[0002] In waste-to-energy plants, the air entering the incinerator needs to be heated to ensure efficient waste incineration. To conserve resources, the exhaust gas from the incinerator is usually used to heat the air. After the heat exchange, the exhaust gas is separated into gas and liquid, and the water in the exhaust gas is recovered.

[0003] In related technologies, heat exchange exhaust gas is passed into a recovery device, which has a drain pipe on its sidewall. A float valve is installed in the drain pipe. When the amount of wastewater in the recovery device increases, the float valve rises, increasing the opening of the drain pipe and allowing more wastewater to escape. When the amount of wastewater in the recovery device decreases, the float valve descends, decreasing the opening of the drain pipe and allowing less wastewater to escape, thereby achieving a balanced liquid level in the recovery device.

[0004] With respect to the above-mentioned related technologies, after long-term use, the float valve is prone to getting stuck, resulting in an imbalance in the adjustment of the liquid level by the float valve. Summary of the Invention

[0005] In order to ensure the liquid level balance in the recovery device, the present application provides a heat exchange exhaust gas recovery method, system, intelligent terminal and storage medium.

[0006] In a first aspect, the present application provides a method for recovering heat exchange exhaust gas, which adopts the following technical solution: A method for recovering heat exchange waste gas, comprising: After the heat exchange exhaust gas passes through the heat exchange device, the heat exchange exhaust gas is passed into a recovery device, the recovery device includes a steam inlet pipe, an exhaust pipe and a drain pipe, the drain pipe is provided with a control valve, the recovery device is used to separate the gas and liquid in the heat exchange exhaust gas to obtain recovered exhaust gas and recovered wastewater, the recovered exhaust gas leaves the recovery device through the exhaust pipe, and the recovered wastewater leaves the recovery device through the drain pipe; Obtaining the real-time liquid level in the recovery device; Calculating a liquid level difference between the real-time liquid level and a first preset liquid level; According to the liquid level difference, the valve opening of the control valve is adjusted so that the real-time liquid level is between the first preset liquid level and a second preset liquid level, and the second preset liquid level is greater than the first preset liquid level.

[0007] By adopting the above technical solution, by real-time monitoring of the liquid level and dynamically adjusting the valve opening so that the real-time liquid level is between the first preset liquid level and the second preset liquid level, it is possible to prevent the recovered waste gas from escaping from the drainage pipe, polluting the environment and affecting the recovery efficiency.

[0008] Optionally, a first real-time flow rate and a second real-time flow rate in the drainage pipe are obtained, wherein the first real-time flow rate is the flow rate of the recycled wastewater before the recycled wastewater passes through the control valve, and the second real-time flow rate is the flow rate of the recycled wastewater after the recycled wastewater passes through the control valve; Obtaining the current valve opening of the control valve; Determining a predicted flow rate in a preset flow mapping table based on the first real-time flow rate and the current valve opening, wherein the flow mapping table is used to represent a mapping relationship between the flow rate of recycled wastewater before and after passing through the control valve and the valve opening; Calculating a flow difference based on the second real-time flow and the predicted flow; If the flow difference is greater than the flow difference threshold, the mapping relationship in the flow mapping table is updated according to the flow difference.

[0009] By adopting the above technical solution, a flow difference is calculated based on the second real-time flow rate and the predicted flow rate. If the flow difference is too large, the mapping relationship in the flow mapping table is updated based on the flow difference, so that the flow prediction is more closely aligned with the current valve state, avoiding valve control failure due to valve performance degradation.

[0010] Optionally, obtaining the wastewater temperature of the recycled wastewater in the drainage pipe; In the temperature-coefficient curve, determining a compensation coefficient corresponding to the wastewater temperature, wherein the compensation coefficient is used to compensate for the error of the control valve caused by the temperature; Calculating a difference between the second real-time flow rate and the predicted flow rate to obtain a flow rate difference; The product of the compensation coefficient and the flow difference is calculated to obtain the flow difference value.

[0011] By employing this technical solution, a compensation coefficient corresponding to the wastewater temperature is determined in the temperature-coefficient curve. The difference between the second real-time flow rate and the predicted flow rate is calculated to obtain the flow difference. The product of the compensation coefficient and the flow difference is then calculated to obtain the flow difference. This eliminates temperature interference with flow measurement, improves the reliability of flow difference calculation, and eliminates the need to set up a flow mapping table for different temperatures.

[0012] Optionally, the steam inlet pipe includes an alkaline steam inlet pipe and an acidic steam inlet pipe, the heat exchange exhaust gas corresponding to the alkaline steam inlet pipe includes alkaline gas, and the heat exchange exhaust gas corresponding to the acidic steam inlet pipe includes acidic gas; the acidic steam inlet pipe is higher than the alkaline steam inlet pipe; Obtaining a first equivalent mass of the alkaline gas in the alkaline steam inlet pipeline and a second equivalent mass of the acidic gas in the acidic steam inlet pipeline; Calculating the product of the first equivalent mass and a preset absorption ratio to obtain a first absorption amount of the alkaline gas; Obtaining a required amount of the acid gas for reaction according to the first absorption amount and a reaction mode between the alkaline gas and the acid gas; obtaining a first absorption ratio of the acid gas according to the reaction demand and the second equivalent mass; Obtaining a target liquid level position according to the first absorption ratio, wherein the target liquid level position is used to represent the distance from the liquid level in the recovery device to the bottom of the acid steam inlet pipe; The valve opening is set according to the target liquid level position.

[0013] By employing this technical solution, the required reaction volume of acidic gas is calculated based on the amount of alkaline gas. The first absorption ratio of the acidic gas is calculated using the required reaction volume and the second equivalent mass. The liquid level in the recovery device is determined based on the first absorption ratio, optimizing the neutralization efficiency of the acidic and alkaline gases and reducing neutralizer waste.

[0014] Optionally, obtaining the pH value of the recycled wastewater; When the pH value is greater than the upper pH value limit or the pH value is less than the lower pH value limit, adjusting the valve opening to a first preset opening; Monitoring changes in the real-time liquid level; If the real-time liquid level is located between the bottom of the alkaline steam inlet pipe and the top of the drainage pipe, the valve opening is adjusted to a second preset opening, which is smaller than the first preset opening.

[0015] By adopting the above technical solution, when the pH value is greater than the upper limit of the pH value or the pH value is less than the lower limit of the pH value, the valve opening is adjusted to the first preset opening to achieve rapid drainage, and when the real-time liquid level is between the bottom of the alkaline steam inlet pipe and the top of the drainage pipe, the valve opening is adjusted to the second preset opening to avoid the recovery waste gas from escaping due to excessive liquid level.

[0016] Optionally, in response to the pH value being greater than the pH lower limit and less than a neutral value, obtaining a third preset liquid level and a fourth preset liquid level; Adjusting the valve opening so that the real-time liquid level is between the third preset liquid level and the fourth preset liquid level; updating the real-time liquid level and the pH value; Obtaining a required amount of the alkaline gas for neutralization according to a difference between the pH value and the neutral value; obtaining a second absorption ratio of the alkaline gas according to the real-time liquid level; The valve opening is adjusted according to the neutralization requirement and the second absorption ratio.

[0017] By adopting the above technical solution, when the pH value is greater than the lower limit and less than the neutral value, the liquid level is controlled between the third preset liquid level and the fourth preset liquid level, thereby ensuring efficient dissolution of the alkaline gas and avoiding excessive addition.

[0018] Optionally, obtaining at least two pieces of liquid level data of the recovery device, wherein the at least two pieces of liquid level data correspond to liquid levels at different positions; Obtaining a quantitative value of liquid level calmness in the recovery device according to the variance of the at least two liquid level data; updating the first absorption ratio according to the liquid level calmness quantified value to obtain an updated absorption ratio; The target liquid level position corresponding to the updated absorption ratio is retrieved from a preset liquid level-ratio mapping table, where the liquid level-ratio mapping table is used for mapping relationship between liquid level position and absorption ratio.

[0019] By adopting the above technical solution, a quantitative value of the liquid level calmness in the recovery device is obtained based on the variance of at least two liquid level data, eliminating the interference of liquid level fluctuations on the absorption ratio calculation and improving the positioning accuracy of the target liquid level.

[0020] In a second aspect, the present application provides a heat exchange exhaust gas recovery system, which adopts the following technical solutions: A heat exchange exhaust gas recovery system, comprising: Acquisition module, used to obtain real-time liquid level and valve opening; A memory for storing a program of the heat exchange exhaust gas recovery method; The program in the processor memory can be loaded and executed by the processor to implement the heat exchange exhaust gas recovery method.

[0021] By adopting the above technical solution, by real-time monitoring of the liquid level and dynamically adjusting the valve opening so that the real-time liquid level is between the first preset liquid level and the second preset liquid level, it is possible to prevent the recovered waste gas from escaping from the drainage pipe, polluting the environment and affecting the recovery efficiency.

[0022] In a third aspect, the present application provides a smart terminal that adopts the following technical solution: An intelligent terminal includes a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and execute any one of the methods described above.

[0023] In a fourth aspect, the present application provides a computer storage medium capable of storing a corresponding program, which has the characteristic of facilitating the liquid level balance in the recovery device, and adopts the following technical solution: A computer-readable storage medium stores a computer program that can be loaded by a processor and execute any of the above-mentioned heat exchange exhaust gas recovery methods.

[0024] In summary, this application includes at least one of the following beneficial technical effects: 1. By real-time monitoring of the liquid level and dynamically adjusting the valve opening to keep the real-time liquid level between the first preset level and the second preset level, it is possible to prevent the recovered waste gas from escaping from the drainage pipe, polluting the environment and affecting the recovery efficiency; 2. Calculate the flow difference based on the second real-time flow and the predicted flow. If the flow difference is too large, update the mapping relationship in the flow mapping table based on the flow difference to make the flow prediction more consistent with the current valve status, avoiding valve control failure due to valve performance degradation; 3. Calculate the required acid gas reaction volume based on the alkaline gas volume. The first absorption ratio of the acid gas is calculated using the required reaction volume and the second equivalent mass. This first absorption ratio is used to determine the liquid level in the recovery unit, optimizing the neutralization efficiency of the acid and alkaline gases and reducing neutralizer waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic diagram of a heat exchange exhaust gas recovery device provided in an embodiment of the present application.

[0026] Figure 2 This is a flow chart of a method for recovering heat exchange waste gas provided in an embodiment of the present application.

[0027] Figure 3 This is a flow chart of a method for updating a traffic mapping table provided in an embodiment of the present application.

[0028] Figure 4 This is a flow chart of a method for calculating flow difference provided in an embodiment of the present application.

[0029] Figure 5 It is a flow chart of a first method for setting a valve opening provided in an embodiment of the present application.

[0030] Figure 6 This is a flow chart of a second method for setting a valve opening provided in an embodiment of the present application.

[0031] Figure 7 This is a flow chart of a third method for setting a valve opening provided in an embodiment of the present application.

[0032] Figure 8It is a flow chart of a liquid level correction method provided in an embodiment of the present application.

[0033] Figure 9 It is a structural schematic diagram of a heat exchange exhaust gas recovery system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of this application more clear, the following Figures 1 to 9 It should be understood that the specific embodiments described herein are only used to explain the present application and are not intended to limit the present application.

[0035] The embodiment of the present application discloses a heat exchange waste gas recovery system. Figure 1 The system includes: a heat exchange device 11 and a recovery device 12. The recovery device 12 includes a steam inlet pipe 121, an exhaust pipe 122 and a drain pipe 123. A control valve 1231 is provided on the drain pipe 123. The recovery device 12 is used to separate the gas and liquid in the heat exchange exhaust gas to obtain recovered exhaust gas and recovered wastewater. The recovered exhaust gas leaves the recovery device 12 from the exhaust pipe 122, and the recovered wastewater leaves the recovery device 12 from the drain pipe 123.

[0036] In some embodiments, the steam inlet pipe 121 includes an alkaline steam inlet pipe and an acidic steam inlet pipe. The heat exchange exhaust gas corresponding to the alkaline steam inlet pipe includes alkaline gas, and the heat exchange exhaust gas corresponding to the acidic steam inlet pipe includes acidic gas; the acidic steam inlet pipe is higher than the alkaline steam inlet pipe.

[0037] The present application discloses a method for recovering heat exchange waste gas. Figure 2 , the method comprising: Step S201: After the heat exchange exhaust gas passes through the heat exchange device, the heat exchange exhaust gas is passed into the recovery device, which includes a steam inlet pipe, an exhaust pipe and a drainage pipe. A control valve is provided on the drainage pipe. The recovery device is used to separate the gas and liquid in the heat exchange exhaust gas to obtain recovered exhaust gas and recovered wastewater. The recovered exhaust gas leaves the recovery device from the exhaust pipe, and the recovered wastewater leaves the recovery device from the drainage pipe.

[0038] Heat exchange exhaust gas originates from the incineration waste gas generated by the waste-to-energy power plant. To recover the heat from the incineration waste gas, the incineration waste gas is passed through a heat exchanger to exchange heat between the incineration waste gas and the air, heating the air. The heated air then enters the waste-to-energy power plant. After the incineration waste gas passes through the heat exchanger, heat exchange exhaust gas is obtained.

[0039] Step S202: Acquire the real-time liquid level in the recovery device.

[0040] Optionally, a liquid level meter is provided in the recovery device, and the real-time liquid level can be obtained through the liquid level meter.

[0041] Furthermore, multiple level gauges can be installed in the recovery device to obtain the level data of each level gauge, calculate the average of the level data, and obtain the real-time level.

[0042] Step S203: Calculating the liquid level difference between the real-time liquid level and the first preset liquid level.

[0043] The first preset liquid level is the acceptable minimum liquid level of the recovery device. When the liquid level in the recovery device is too low, the drainage pipe will be exposed to the liquid surface, causing the recovered waste gas to escape from the drainage pipe.

[0044] Optionally, the first preset liquid level is the level at which the recycled wastewater reaches the top of the drainage pipe. Furthermore, to reduce the probability of recycled waste gas escaping from the drainage pipe, a target liquid level is obtained when the recycled wastewater reaches the top of the drainage pipe. The sum of the target liquid level and the preset liquid level error is calculated to obtain the first preset liquid level.

[0045] Step S204: adjusting the valve opening of the control valve according to the liquid level difference so that the real-time liquid level is between the first preset liquid level and the second preset liquid level, and the second preset liquid level is greater than the first preset liquid level.

[0046] In one embodiment, the valve opening is determined based on the liquid level difference from a preset liquid level difference-valve opening mapping table. The liquid level difference and valve opening are positively correlated, meaning that the greater the liquid level difference, the greater the valve opening. The liquid level difference-valve opening mapping table is used to record the corresponding relationship between the liquid level difference and the valve opening.

[0047] The second preset liquid level is a preset empirical value, and a technician can adjust the value of the second preset liquid level.

[0048] By adopting the above technical solution, by real-time monitoring of the liquid level and dynamically adjusting the valve opening so that the real-time liquid level is between the first preset liquid level and the second preset liquid level, it is possible to prevent the recovered waste gas from escaping from the drainage pipe, polluting the environment and affecting the recovery efficiency.

[0049] In the following embodiments, during the use of the control valve, the control valve itself will gradually age over time, thereby affecting the opening control of the control valve. To solve the above problem, the embodiment of the present application discloses a method for updating the flow mapping table. Figure 3 , the method comprising: Step S301: Obtain a first real-time flow rate and a second real-time flow rate in the drainage pipe, wherein the first real-time flow rate is the flow rate of the recycled wastewater before it passes through the control valve, and the second real-time flow rate is the flow rate of the recycled wastewater after it passes through the control valve.

[0050] Optionally, a first flow meter and a second flow meter are provided in the drainage pipe. The first flow meter and the second flow meter are provided on either side of the control valve, with the first flow meter provided on the side closer to the recovery device and the second flow meter provided on the side farther from the recovery device. The first real-time flow rate can be obtained using the first flow meter, and the second real-time flow rate can be obtained using the second flow meter.

[0051] Furthermore, there may be multiple first flow meters, and a first flow reading of each first flow meter is obtained, and an average of the first flow readings is calculated to obtain the first real-time flow.

[0052] Furthermore, there may be multiple second flow meters, and a second flow reading of each second flow meter is obtained, and an average of the second flow readings is calculated to obtain the second real-time flow.

[0053] Step S302: Acquire the current valve opening of the control valve.

[0054] Optionally, a positioner is installed inside the control valve, and the valve opening of the control valve can be output through the positioner to obtain the current valve opening.

[0055] Step S303: Determine the predicted flow rate in a preset flow mapping table according to the first real-time flow rate and the current valve opening. The flow mapping table is used to represent the mapping relationship between the recycled wastewater flow rate before and after passing through the control valve and the valve opening.

[0056] The flow mapping table records the ideal relationship between the recycled wastewater flow rate before and after the control valve and the valve opening. This means that the control valve itself is not aged or damaged. Furthermore, the flow mapping table can be obtained by measuring the control valve at the factory.

[0057] The predicted flow rate represents the recycled wastewater flow rate after the control valve under ideal conditions.

[0058] Step S304: Calculate the flow difference based on the second real-time flow and the predicted flow.

[0059] The flow difference is used to describe the error between the second real-time flow and the predicted flow. The calculation method of the flow difference can be referred to Figure 4 The embodiments shown will not be described in detail here.

[0060] Step S305: If the flow difference is greater than the flow difference threshold, the mapping relationship in the flow mapping table is updated according to the flow difference.

[0061] The flow difference threshold is a preset empirical value, and technicians can adjust the specific value of the flow difference threshold according to actual needs.

[0062] If the flow difference is greater than the flow difference threshold, the control valve may be aging or corroded, resulting in a significant deviation between the second real-time flow rate and the predicted flow rate. Therefore, the flow mapping table needs to be updated. For example, the flow mapping table is searched for a mapping relationship between the first real-time flow rate, valve opening, and predicted flow rate, and this mapping relationship is updated to the first real-time flow rate, valve opening, and second real-time flow rate. Furthermore, the mapping relationship in the flow mapping table is set to be upstream flow rate, valve opening, and valve flow rate, and the mapping relationship is updated to the upstream flow rate, valve opening, and (valve flow rate + flow difference).

[0063] In some other embodiments, if the flow difference is less than the flow difference threshold, it means that there is no large difference between the second real-time flow and the predicted flow, and the operating status of the control valve is good.

[0064] By adopting the above technical solution, a flow difference is calculated based on the second real-time flow rate and the predicted flow rate. If the flow difference is too large, the mapping relationship in the flow mapping table is updated based on the flow difference, so that the flow prediction is more closely aligned with the current valve state, avoiding valve control failure due to valve performance degradation.

[0065] In the following embodiments, when calculating the flow difference, since the recycled wastewater itself has a certain temperature, the control valve will be affected by thermal expansion and contraction, resulting in inaccurate valve opening. Therefore, in this application, when calculating the flow difference, the flow difference will be corrected according to the temperature to ensure the accuracy of subsequent steps. This embodiment of the application discloses a method for calculating the flow difference. Figure 4 , the method comprising: Step S401: Obtaining the wastewater temperature of the recovered wastewater in the drainage pipe.

[0066] Optionally, a temperature sensor is provided in the drainage pipe, and the wastewater temperature can be obtained through the temperature sensor.

[0067] Furthermore, multiple temperature sensors can be installed in the drainage pipe to obtain temperature data from each temperature sensor, and the mean of the temperature data is calculated to obtain the wastewater temperature.

[0068] Step S402: In the temperature-coefficient curve, a compensation coefficient corresponding to the wastewater temperature is determined. The compensation coefficient is used to compensate for the error of the control valve caused by the temperature.

[0069] The temperature-coefficient curve can be obtained by technicians through repeated experimental measurements.

[0070] Step S403: Calculate the difference between the second real-time flow rate and the predicted flow rate to obtain the flow rate difference.

[0071] The flow difference refers to the difference between the second real-time flow and the predicted flow.

[0072] Step S404: Calculate the product of the compensation coefficient and the flow difference to obtain the flow difference value.

[0073] The product of the compensation coefficient and the flow difference is calculated, and the flow difference can be adjusted using the wastewater temperature to make the flow difference consistent with the effect of the wastewater temperature on the control valve.

[0074] By employing this technical solution, a compensation coefficient corresponding to the wastewater temperature is determined in the temperature-coefficient curve. The difference between the second real-time flow rate and the predicted flow rate is calculated to obtain the flow difference. The product of the compensation coefficient and the flow difference is then calculated to obtain the flow difference. This eliminates temperature interference with flow measurement, improves the reliability of flow difference calculation, and eliminates the need to set up a flow mapping table for different temperatures.

[0075] In the following embodiment, the steam inlet pipe of the recovery device may include an alkaline steam inlet pipe for introducing alkaline gas and an acidic steam inlet pipe for passing acidic gas, so that the alkaline gas and the acidic gas are dissolved in the recovered wastewater and acid-base neutralization is achieved. Therefore, the embodiment of the present application discloses a method for setting the valve opening. Figure 5 , the method comprising: Step S501: obtaining a first equivalent mass of alkaline gas in the alkaline steam inlet pipeline and a second equivalent mass of acidic gas in the acidic steam inlet pipeline.

[0076] Optionally, the steam inlet pipe includes an alkaline steam inlet pipe and an acidic steam inlet pipe. The heat exchange exhaust gas corresponding to the alkaline steam inlet pipe includes alkaline gas, and the heat exchange exhaust gas corresponding to the acidic steam inlet pipe includes acidic gas. The acidic steam inlet pipe is higher than the alkaline steam inlet pipe. Exemplarily, the acidic gas is sulfur dioxide, and the alkaline gas is ammonia or a gas containing calcium hydroxide powder.

[0077] Alternatively, the alkaline gas and the acidic gas are output from an incinerator in a waste-to-energy plant that burns different types of materials. For example, sulfur dioxide is a product of the combustion of sulfur-containing compounds, and ammonia is generated by the decomposition of nitrogen-containing waste.

[0078] The first equivalent mass refers to the mass of alkaline gas entering the recovery device from the alkaline steam inlet pipe per unit time. Optionally, the content and type of the alkaline gas are obtained by a first gas analyzer. The first equivalent mass is obtained based on the content and type of the alkaline gas.

[0079] The second equivalent mass refers to the mass of acid gas entering the recovery device from the acid steam inlet pipeline per unit time. Optionally, the acid gas content and type are obtained using a second gas analyzer. The second equivalent mass is calculated based on the acid gas content and type.

[0080] Step S502: Calculate the product of the first equivalent mass and the preset absorption ratio to obtain a first absorption amount of the alkaline gas.

[0081] The preset absorption ratio refers to the proportion of alkaline gas absorbed by the recycled wastewater. This ratio is determined when the recycled wastewater level is above the alkaline steam inlet pipe. In actual scenarios, the amount of alkaline gas generated is less than the amount of acidic gas generated. Therefore, during conventional treatment, the positional relationship between the liquid level and the acidic steam inlet pipe must be adjusted while the liquid level remains above the alkaline steam inlet pipe. This controls the amount of acidic gas dissolved in the recycled wastewater and achieves a balanced acid-base balance in the recycled wastewater.

[0082] Step S503: Obtaining a required amount of the acid gas for reaction according to the first absorption amount and the reaction mode between the alkaline gas and the acid gas.

[0083] The reaction mode refers to the chemical reaction formula of alkaline gas and acidic gas. For example, sulfur dioxide dissolves in water to form H2SO3, H2SO3 + NH3 → NH4HSO3.

[0084] The reaction demand refers to the mass of acidic gas required to neutralize the first absorbed amount of alkaline gas.

[0085] Step S504: Obtaining a first absorption ratio of the acid gas according to the reaction demand and the second equivalent mass.

[0086] The first absorption ratio refers to the ratio of acid gas absorbed by the recycled wastewater. This first absorption ratio is related to the position of the liquid level. When the liquid level is between the top and bottom of the acid steam inlet pipe, the higher the liquid level, the greater the contact area and duration of the acid gas with the recycled wastewater when entering the acid recovery device. Therefore, in this embodiment, the first absorption ratio of the acid gas is adjusted by controlling the liquid level, and the amount of acid gas dissolved in the recycled wastewater is adjusted accordingly.

[0087] Exemplarily, the ratio of the second equivalent mass to the reaction requirement is calculated to obtain the first absorption ratio.

[0088] Step S505: obtaining a target liquid level position according to the first absorption ratio. The target liquid level position is used to represent the distance from the liquid level in the recovery device to the bottom of the acid steam inlet pipe.

[0089] For example, in the first absorption ratio-liquid level mapping table, the target liquid level position is determined according to the first absorption ratio. The first absorption ratio-liquid level mapping table is used to record the mapping relationship between the first absorption ratio of the acid gas and the liquid level.

[0090] Optionally, a target liquid level height is obtained according to the target liquid level position and the position of the acid steam inlet pipe in the recovery device. The target liquid level height refers to the liquid level of the recovered wastewater in the recovery device.

[0091] Step S506: setting the valve opening according to the target liquid level position.

[0092] Exemplarily, with the target liquid level position as the target, the valve opening is adjusted to maintain the liquid level of the recycled wastewater at the target liquid level position.

[0093] By employing this technical solution, the required reaction volume of acidic gas is calculated based on the amount of alkaline gas. The first absorption ratio of the acidic gas is calculated using the required reaction volume and the second equivalent mass. The liquid level in the recovery device is determined based on the first absorption ratio, optimizing the neutralization efficiency of the acidic and alkaline gases and reducing neutralizer waste.

[0094] In the following embodiment, the pH value of the recycled wastewater may be abnormal, making it difficult to adjust the pH value of the recycled wastewater by introducing acidic gas and alkaline gas. For this reason, the embodiment of the present application discloses a second method for setting the valve opening. Figure 6 , the method comprising: Step S601: Obtaining the pH value of the recycled wastewater.

[0095] Optionally, a pH meter is provided at the drainage pipe of the recovery device, and the pH value of the recovered wastewater is obtained by reading the pH meter.

[0096] Step S602 : When the pH value is greater than the upper pH value limit or the pH value is less than the lower pH value limit, adjusting the valve opening to a first preset opening.

[0097] The upper limit of pH value and the lower limit of pH value are preset empirical values, for example, the upper limit of pH value is 8.7 and the lower limit of pH value is 5.0.

[0098] Exemplarily, the first preset opening is 90%. When the control valve is at the first preset opening, the liquid level in the recovery device will drop at a faster rate.

[0099] Step S603: monitor the change of the real-time liquid level.

[0100] Exemplarily, the real-time liquid level is acquired once every preset time period, wherein the preset time period is a preset value, for example, the preset time period is 1 second.

[0101] Step S604: If the real-time liquid level is between the bottom of the alkaline steam inlet pipe and the top of the drainage pipe, the valve opening is adjusted to a second preset opening, which is smaller than the first preset opening.

[0102] When the real-time liquid level is between the bottom of the alkaline steam inlet pipe and the top of the drain pipe, the valve opening needs to be promptly reduced to prevent the liquid level from dropping too quickly, potentially exposing the drain pipe and allowing gas to escape from the drain pipe. For example, the second preset opening is 5%. At this second preset opening, the liquid level in the recovery device can be maintained stable or its rate of rise can be less than the preset rate.

[0103] Furthermore, after adjusting the valve opening to the second preset opening, the heat exchange exhaust gas continues to enter the recovery device, which in turn means that the wastewater in the heat exchange exhaust gas is continuously replenished to the recovery device. Meanwhile, the valve opening is maintained at the second preset opening, allowing a certain amount of recycled wastewater to exit, ensuring a stable liquid level within the recovery device. Through this process, the pH value of the recycled wastewater can be brought closer to a neutral value.

[0104] By adopting the above technical solution, when the pH value is greater than the upper limit of the pH value or the pH value is less than the lower limit of the pH value, the valve opening is adjusted to the first preset opening to achieve rapid drainage, and when the real-time liquid level is between the bottom of the alkaline steam inlet pipe and the top of the drainage pipe, the valve opening is adjusted to the second preset opening to avoid the recovery waste gas from escaping due to excessive liquid level.

[0105] In the following embodiment, the bottom of the acidic steam inlet pipe is lower than the top of the alkaline steam inlet pipe. At this time, the acidic steam inlet pipe and the alkaline steam inlet pipe will overlap in the horizontal direction. When the recycled wastewater is weakly acidic, it is necessary to appropriately reduce the amount of dissolved alkaline gas to better control the pH value of the recycled wastewater. This embodiment of the application discloses a third method for setting the valve opening. Figure 7 , the method comprising: Step S701 : In response to the pH value being greater than the pH lower limit and less than the neutral value, obtaining a third preset liquid level and a fourth preset liquid level.

[0106] Assuming the bottom of the acidic steam inlet pipe is lower than the top of the alkaline steam inlet pipe, the third preset liquid level corresponds to the bottom of the acidic steam inlet pipe, the fourth preset liquid level corresponds to the horizontal overlap of the acidic and alkaline steam inlet pipes, and the first absorption ratio corresponding to the fourth preset liquid level is less than the minimum preset ratio. When the liquid level is a short distance above the bottom of the acidic steam inlet pipe, the recycled wastewater's absorption of acid gases is poor, and it can be considered that the recycled wastewater has essentially absorbed no acid gases.

[0107] Step S702: adjusting the valve opening so that the real-time liquid level is between the third preset liquid level and the fourth preset liquid level.

[0108] Exemplarily, the valve opening is adjusted to control the discharge rate of the recovered wastewater in the recovery device to adjust the real-time liquid level so that the real-time liquid level is between the third preset liquid level and the fourth preset liquid level.

[0109] Step S703: Update the real-time liquid level and pH value.

[0110] Exemplarily, the real-time liquid level and pH value are acquired once every preset time period, wherein the preset time period is a preset value, for example, 1 second.

[0111] Step S704: Obtaining the neutralization requirement of the alkaline gas according to the difference between the pH value and the neutral value.

[0112] Neutralization demand refers to the mass of alkaline gas required to make the pH value of the recovered waste gas reach a neutral value.

[0113] Step S705: obtaining a second absorption ratio of the alkaline gas according to the real-time liquid level.

[0114] For example, in the second absorption ratio-liquid level mapping table, the target second absorption ratio is determined according to the real-time liquid level. The second absorption ratio-liquid level mapping table is used to record the mapping relationship between the second absorption ratio of the alkaline gas and the liquid level.

[0115] Step S706: adjusting the valve opening according to the neutralization demand and the second absorption ratio.

[0116] For example, the product of the first equivalent mass and the second absorption ratio is calculated to obtain the mass of alkaline gas absorbed per unit time. The ratio of the neutralization requirement to the absorbed mass is calculated to obtain the absorption time. During the absorption time, the valve opening is adjusted so that the real-time liquid level is between the third preset liquid level and the fourth preset liquid level.

[0117] By adopting the above technical solution, when the pH value is greater than the lower limit and less than the neutral value, the liquid level is controlled between the third preset liquid level and the fourth preset liquid level, thereby ensuring efficient dissolution of the alkaline gas and avoiding excessive addition.

[0118] In the following embodiment, when the heat exchange exhaust gas enters the recovery device through the steam inlet pipe, the heat exchange exhaust gas will cause the liquid level to be disturbed, thereby affecting the accuracy of the liquid level. Therefore, the embodiment of the present application discloses a liquid level correction method. Figure 8 , the method comprising: Step S801: Acquire at least two pieces of liquid level data of a recovery device, where the at least two pieces of liquid level data correspond to liquid levels at different positions.

[0119] Optionally, the liquid level data is obtained by a liquid level gauge installed in the recovery device, and the distance between the liquid level gauges needs to be greater than a preset installation distance, which is a preset empirical value to ensure the independence of liquid level data sampling.

[0120] Step S802: Obtaining a quantitative value of the liquid level calmness in the recovery device according to the variance of at least two liquid level data.

[0121] Optionally, the variance of at least two liquid level data is calculated and normalized to obtain a quantitative value of the liquid level calmness in the recovery device.

[0122] Step S803: Retrieve the theoretical liquid level position corresponding to the first absorption ratio from a preset liquid level-ratio mapping table, where the liquid level-ratio mapping table is used for mapping the liquid level position and the absorption ratio.

[0123] The data in the liquid level-proportion mapping table can be obtained by technicians through repeated experiments.

[0124] Step S804: updating the theoretical liquid level position according to the liquid level calmness quantization value to obtain the target liquid level position.

[0125] For example, the liquid level height corresponding to the theoretical liquid level position is determined, the product of the liquid level calmness quantization value and the theoretical liquid level is calculated to obtain the target liquid level height, and the target liquid level height is converted into the target liquid level position.

[0126] By adopting the above technical solution, a quantitative value of the liquid level calmness in the recovery device is obtained based on the variance of at least two liquid level data, eliminating the interference of liquid level fluctuations on the absorption ratio calculation and improving the positioning accuracy of the target liquid level.

[0127] Based on the same inventive concept, the present application provides a heat exchange exhaust gas recovery system, please refer to Figure 9 , the system comprises: Acquisition module 901, used to obtain real-time liquid level and valve opening; Memory 902, used to store the program of the heat exchange exhaust gas recovery method; Processor 903, the program in the memory can be loaded and executed by the processor to implement the above-mentioned heat exchange exhaust gas recovery method.

[0128] By adopting the above technical solution, by real-time monitoring of the liquid level and dynamically adjusting the valve opening so that the real-time liquid level is between the first preset liquid level and the second preset liquid level, it is possible to prevent the recovered waste gas from escaping from the drainage pipe, polluting the environment and affecting the recovery efficiency.

[0129] Those skilled in the art will clearly understand that for the sake of convenience and brevity, the division of the above-mentioned functional modules is only used as an example for illustration. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working processes of the above-mentioned systems, devices, and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0130] An embodiment of the present application provides a computer-readable storage medium storing a computer program that can be loaded by a processor and executed to implement a method for recovering heat exchange exhaust gas.

[0131] Computer storage media include, for example, various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical disks.

[0132] Based on the same inventive concept, an embodiment of the present application provides an intelligent terminal, including a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and execute a method for recovering heat exchange exhaust gas.

[0133] Those skilled in the art will clearly understand that for the sake of convenience and brevity, the division of the above-mentioned functional modules is only used as an example for illustration. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working processes of the above-mentioned systems, devices, and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0134] The above are all preferred embodiments of the present application and are not intended to limit the scope of protection of this application. Unless otherwise specified, any feature disclosed in this specification (including the abstract and drawings) may be replaced by other equivalent or similar features. In other words, unless otherwise specified, each feature is merely an example of a series of equivalent or similar features.

Claims

1. A method for recovering heat exchange waste gas, characterized in that: The method comprises: After the heat exchange exhaust gas passes through the heat exchange device, the heat exchange exhaust gas is passed into a recovery device, the recovery device includes a steam inlet pipe, an exhaust pipe and a drain pipe, the drain pipe is provided with a control valve, the recovery device is used to separate the gas and liquid in the heat exchange exhaust gas to obtain recovered exhaust gas and recovered wastewater, the recovered exhaust gas leaves the recovery device through the exhaust pipe, and the recovered wastewater leaves the recovery device through the drain pipe; Obtaining the real-time liquid level in the recovery device; Calculating a liquid level difference between the real-time liquid level and a first preset liquid level; According to the liquid level difference, the valve opening of the control valve is adjusted so that the real-time liquid level is between the first preset liquid level and a second preset liquid level, and the second preset liquid level is greater than the first preset liquid level.

2. The heat exchange exhaust gas recovery method according to claim 1, characterized in that: The method further comprises: Obtaining a first real-time flow rate and a second real-time flow rate in the drainage pipe, wherein the first real-time flow rate is the flow rate of the recycled wastewater before it passes through the control valve, and the second real-time flow rate is the flow rate of the recycled wastewater after it passes through the control valve; Obtaining the current valve opening of the control valve; Determining a predicted flow rate in a preset flow mapping table based on the first real-time flow rate and the current valve opening, wherein the flow mapping table is used to represent a mapping relationship between the flow rate of recycled wastewater before and after passing through the control valve and the valve opening; Calculating a flow difference based on the second real-time flow and the predicted flow; If the flow difference is greater than the flow difference threshold, the mapping relationship in the flow mapping table is updated according to the flow difference.

3. The heat exchange exhaust gas recovery method according to claim 2, characterized in that: The calculating a flow difference according to the second real-time flow and the predicted flow includes: Obtaining the wastewater temperature of the recycled wastewater in the drainage pipe; In the temperature-coefficient curve, determining a compensation coefficient corresponding to the wastewater temperature, wherein the compensation coefficient is used to compensate for the error of the control valve caused by the temperature; Calculating a difference between the second real-time flow rate and the predicted flow rate to obtain a flow rate difference; The product of the compensation coefficient and the flow difference is calculated to obtain the flow difference value.

4. The heat exchange exhaust gas recovery method according to claim 1, characterized in that: The steam inlet pipe includes an alkaline steam inlet pipe and an acidic steam inlet pipe, the heat exchange exhaust gas corresponding to the alkaline steam inlet pipe includes alkaline gas, and the heat exchange exhaust gas corresponding to the acidic steam inlet pipe includes acidic gas; the acidic steam inlet pipe is higher than the alkaline steam inlet pipe; The method further comprises: Obtaining a first equivalent mass of the alkaline gas in the alkaline steam inlet pipeline and a second equivalent mass of the acidic gas in the acidic steam inlet pipeline; Calculating the product of the first equivalent mass and a preset absorption ratio to obtain a first absorption amount of the alkaline gas; Obtaining a required amount of the acid gas for reaction according to the first absorption amount and a reaction mode between the alkaline gas and the acid gas; obtaining a first absorption ratio of the acid gas according to the reaction demand and the second equivalent mass; Obtaining a target liquid level position according to the first absorption ratio, wherein the target liquid level position is used to represent the distance from the liquid level in the recovery device to the bottom of the acid steam inlet pipe; The valve opening is set according to the target liquid level position.

5. The heat exchange exhaust gas recovery method according to claim 4, characterized in that: The method further comprises: Obtaining the pH value of the recycled wastewater; When the pH value is greater than the upper pH value limit or the pH value is less than the lower pH value limit, adjusting the valve opening to a first preset opening; Monitoring changes in the real-time liquid level; If the real-time liquid level is located between the bottom of the alkaline steam inlet pipe and the top of the drainage pipe, the valve opening is adjusted to a second preset opening, which is smaller than the first preset opening.

6. The heat exchange exhaust gas recovery method according to claim 5, characterized in that: The bottom of the acidic steam inlet pipe is lower than the top of the alkaline steam inlet pipe; The method further comprises: In response to the pH value being greater than the pH lower limit and less than a neutral value, obtaining a third preset liquid level and a fourth preset liquid level; Adjusting the valve opening so that the real-time liquid level is between the third preset liquid level and the fourth preset liquid level; updating the real-time liquid level and the pH value; Obtaining a required amount of the alkaline gas for neutralization according to a difference between the pH value and the neutral value; obtaining a second absorption ratio of the alkaline gas according to the real-time liquid level; The valve opening is adjusted according to the neutralization requirement and the second absorption ratio.

7. The heat exchange exhaust gas recovery method according to claim 4, characterized in that: Obtaining a target liquid level position according to the first absorption ratio includes: Acquire at least two pieces of liquid level data of the recovery device, wherein the at least two pieces of liquid level data correspond to liquid levels at different positions; Obtaining a quantitative value of liquid level calmness in the recovery device according to the variance of the at least two liquid level data; Retrieving a theoretical liquid level position corresponding to the first absorption ratio from a preset liquid level-ratio mapping table, wherein the liquid level-ratio mapping table is used for mapping the liquid level position and the absorption ratio; The theoretical liquid level position is updated according to the liquid level calmness quantization value to obtain a target liquid level position.

8. A heat exchange exhaust gas recovery system, characterized in that: The system is used to perform the heat exchange exhaust gas recovery method according to any one of claims 1 to 7, and the system comprises: Acquisition module, used to obtain real-time liquid level and valve opening; A memory for storing a program of the heat exchange exhaust gas recovery method; The program in the processor memory can be loaded and executed by the processor to implement the heat exchange exhaust gas recovery method.

9. An intelligent terminal, characterized in that: The method comprises a memory and a processor, wherein the memory stores a computer program that can be loaded by the processor and execute the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that A computer program is stored which can be loaded by a processor and execute the method according to any one of claims 1 to 7.

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