A high-temperature flue gas purification method and system

Abstract

The present invention relates to the field of flue gas purification, and particularly to a high-temperature flue gas purification method and system. The method first obtains the flue gas temperatures at the inlet and outlet of the independent cooling channel section and the flue gas temperatures and flue gas humidity at the inlet and outlet of the mixed cooling channel section at the current moment, and simultaneously obtains the outside air temperature and the air intake volume in the air inlet channel communicating with the mixed cooling channel section, adjusts the water spray volume of the independent cooling channel section, and based on the obtained real-time water spray volume, first cools the flue gas in the independent cooling channel section. Based on the obtained final atomized water content and the final air intake volume, the flue gas in the mixed cooling channel section is cooled again to obtain the finally cooled flue gas, and the finally cooled flue gas is purified. The present invention can effectively reduce the temperature of the high-temperature flue gas to a reasonable range and improve the purification effect on the high-temperature flue gas.

Description

Technical Field

[0001] The present invention relates to the field of flue gas purification, and particularly to a high-temperature flue gas purification method and system. Background Art

[0002] Flue gas purification is an important branch in the field of industrial environmental protection. Dust removal is a key process in flue gas purification. Currently, bag filters are usually used for high-temperature flue gas dust removal. However, due to the complexity of the industrial environment, under the influence of factors such as fuel, combustion efficiency, and combustion temperature requirements, the temperature of the discharged high-temperature flue gas will vary greatly. The temperature resistance range of bag filters is relatively low, and it is difficult to adapt to the repeatedly changing high-temperature environment. Therefore, in order to improve the purification effect of high-temperature flue gas, it is necessary to cool down the high-temperature flue gas in advance.

[0003] In related technologies, the temperature of high-temperature flue gas is reduced by introducing external cold air or atomized water into the high-temperature flue gas. However, the method of introducing external cold air has limited ability to control the flue gas temperature. To achieve a greater degree of temperature control, a large amount of external air needs to be introduced, increasing the workload. And for flue gas with a relatively low temperature, the method of introducing atomized water will greatly increase the humidity of the flue gas, resulting in bag hardening or pipeline corrosion, thus making it impossible to effectively cool down the high-temperature flue gas through the existing methods and reducing the purification effect of the high-temperature flue gas. Summary of the Invention

[0004] In order to solve the technical problem that the existing methods cannot effectively cool down the high-temperature flue gas and reduce the purification effect of the high-temperature flue gas, the purpose of the present invention is to provide a high-temperature flue gas purification method and system, and the specific technical solutions adopted are as follows:

[0005] The present invention provides a high-temperature flue gas purification method, and the method includes:

[0006] Obtain the flue gas temperatures at the inlet and outlet of the independent cooling channel section and the flue gas temperatures and flue gas humidity at the inlet and outlet of the mixed cooling channel section at the current moment, and at the same time obtain the external air temperature and air intake volume in the air intake channel connected to the mixed cooling channel section;

[0007] Adjust the water spraying amount of the independent cooling channel section according to the flue gas temperatures at the inlet and outlet of the independent cooling channel section to obtain the real-time water spraying amount of the independent cooling channel section; based on the real-time water spraying amount, cool down the flue gas in the independent cooling channel section to obtain the initially cooled flue gas;

[0008] Obtain the initial atomized water content and the initial air intake of the air inlet passage according to the flue gas temperature and the flue gas humidity at the inlet of the mixed cooling passage section, as well as the outside air temperature and the air intake in the air inlet passage; adjust the initial atomized water content and the initial air intake according to the flue gas temperature and the flue gas humidity at the outlet of the mixed cooling passage section to obtain the final atomized water content and the final air intake of the air inlet passage; cool down the initial cooled-down flue gas in the mixed cooling passage section based on the final atomized water content and the final air intake to obtain the final cooled-down flue gas;

[0009] Carry out purification treatment on the final cooled-down flue gas.

[0010] Further, the obtaining of the real-time water spray amount of the independent cooling passage section includes:

[0011] Use the flue gas temperature at the inlet of the independent cooling passage section as the numerator, use the preset parameter as the denominator, and use the ratio as the flue gas temperature ratio value at the inlet of the independent cooling passage section; use the product value of the preset water spray amount of the nozzle of the independent cooling passage section and the flue gas temperature ratio value at the inlet of the independent cooling passage section as the initial water spray amount of the independent cooling passage section;

[0012] Use the difference between the flue gas temperature at the outlet of the independent cooling passage section and the preset first high temperature threshold as the temperature deviation value at the outlet of the independent cooling passage section; use the product value of the preset first feedback adjustment coefficient and the temperature deviation value as the water spray adjustment amount of the independent cooling passage section;

[0013] Use the sum value of the initial water spray amount and the water spray adjustment amount as the real-time water spray amount of the independent cooling passage section.

[0014] Further, the obtaining of the initial cooled-down flue gas includes:

[0015] Use the nozzle in the independent cooling passage section to spray and water-cool the flue gas in the independent cooling passage section with the real-time water spray amount to obtain the initial cooled-down flue gas.

[0016] Further, the obtaining of the initial atomized water content and the initial air intake of the air inlet passage includes:

[0017] Input the flue gas temperature at the inlet of the mixed cooling passage section into the optimal atomized water content model, and the optimal atomized water content of the mixed cooling passage section is output by the optimal atomized water content model;

[0018] Use the sum value of the air intake in the air inlet passage and the air intake of the flue gas in the pipeline as the comprehensive gas volume of the mixed cooling passage section; use the product value of the optimal atomized water content and the comprehensive gas volume as the optimal water content of the mixed cooling passage section;

[0019] Take the product value of the intake air volume of the flue gas in the pipeline and the humidity of the flue gas at the inlet of the mixed cooling channel section as the moisture content of the flue gas at the inlet of the mixed cooling channel section;

[0020] Take the difference between the optimal moisture content and the moisture content of the flue gas as the numerator, take the intake air volume in the air inlet channel as the denominator, and take the ratio as the initial atomized water content of the air inlet channel;

[0021] Obtain the initial intake air volume of the air inlet channel according to the flue gas temperature at the inlet of the mixed cooling channel section, the outside air temperature in the air inlet channel, the intake air volume of the flue gas in the pipeline, and the initial atomized water content of the mixed cooling channel section.

[0022] Further, the obtaining of the initial intake air volume of the air inlet channel includes:

[0023] Obtain the initial intake air volume of the air inlet channel based on the calculation formula of the initial intake air volume of the air inlet channel. The calculation formula of the initial intake air volume of the mixed cooling channel section is:

[0024]

[0025] Wherein, represents the initial intake air volume of the air inlet channel; represents the intake air volume of the flue gas in the pipeline; represents the density of the flue gas in the pipeline; represents the specific heat capacity of the flue gas in the pipeline; represents the flue gas temperature at the inlet of the mixed cooling channel section; represents the preset second high temperature threshold; represents the density of the outside air in the air inlet channel; represents the specific heat capacity of the outside air in the air inlet channel; represents the initial atomized water content of the air inlet channel; represents the specific heat capacity of water; represents the outside air temperature in the air inlet channel.

[0026] Further, the obtaining of the final atomized water content and the final intake air volume of the air inlet channel includes:

[0027] Take the difference between the flue gas temperature at the outlet of the mixed cooling channel section and the preset second high temperature threshold as the numerator, take the preset second high temperature threshold as the denominator, and take the ratio as the temperature performance value at the outlet of the mixed cooling channel section;

[0028] Take the difference between the flue gas humidity at the outlet of the mixed cooling channel section and the preset humidity threshold as the numerator, take the preset humidity threshold as the denominator, and take the ratio as the humidity accumulation at the outlet of the mixed cooling channel section;

[0029] Obtain the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage according to the temperature performance value and the humidity accumulation amount at the outlet of the mixed cooling passage section;

[0030] Take the sum value of the initial atomized water content and the atomized water adjustment amount of the air inlet passage as the final atomized water content of the air inlet passage, and take the sum value of the initial air intake amount and the air intake adjustment amount of the air inlet passage as the final air intake amount of the air inlet passage.

[0031] Further, the obtaining of the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage includes:

[0032] Based on the calculation formulas of the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage, obtain the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage. The calculation formulas of the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage are:

[0033]

[0034]

[0035] Wherein, represents the air intake adjustment amount of the air inlet passage; represents the atomized water adjustment amount of the air inlet passage; represents a preset second feedback adjustment coefficient; represents the humidity accumulation amount at the outlet of the mixed cooling passage section; represents the temperature performance value at the outlet of the mixed cooling passage section; represents a preset adjustment parameter; represents an activation function.

[0036] Further, the obtaining of the finally cooled flue gas includes:

[0037] Adjust the operating power of the cooling fan and the nozzle in the air inlet passage so that the air intake of the cooling fan is the final air intake amount, and at the same time make the content of moisture in the outside air in the air inlet passage be the final atomized water content. Mix the moisture ejected from the nozzle with the outside air, and use the outside air containing moisture to cool the initial cooled flue gas in the mixed cooling passage section to obtain the finally cooled flue gas.

[0038] Further, the purification treatment of the finally cooled flue gas includes:

[0039] Perform dehydration treatment on the finally cooled flue gas to obtain the dehydrated finally cooled flue gas, and sequentially pass the dehydrated finally cooled flue gas through a dust collector, a desulfurization tower and a denitration reactor for purification treatment.

[0040] The present invention also provides a high-temperature flue gas purification system, which includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the steps of any one of the high-temperature flue gas purification methods are implemented.

[0041] The present invention has the following beneficial effects:

[0042] Considering that the existing methods cannot effectively cool high-temperature flue gas and reduce the purification effect of high-temperature flue gas, the present invention first obtains the flue gas temperatures at the inlet and outlet of the independent cooling channel section and the flue gas temperatures and flue gas humidity at the inlet and outlet of the mixed cooling channel section at the current moment, and simultaneously obtains the outside air temperature and the air intake volume in the air inlet channel communicating with the mixed cooling channel section. Subsequently, based on this data and by combining two methods of introducing outside cold air and atomized water, the high-temperature flue gas in the pipeline can be effectively cooled. Since the temperature of the flue gas in the pipeline is relatively high before cooling treatment, first, through the obtained real-time water injection amount, the flue gas in the independent cooling channel section is cooled for the first time by introducing atomized water, so that the temperature of the flue gas can rapidly drop. Then, through the obtained final atomized water content and final air intake volume of the air inlet channel, the initially cooled flue gas in the mixed cooling channel section is cooled again by introducing a mixture of outside cold air and atomized water. While reasonably coordinating the usage amounts of atomized water and outside cold air and reducing unnecessary energy consumption, the cooling effect is ensured, and the temperature of the high-temperature flue gas in the pipeline is reduced to a reasonable range, thereby improving the purification effect of high-temperature flue gas. Description of the Drawings

[0043] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0044] Figure 1 It is a flowchart of a high-temperature flue gas purification method provided by an embodiment of the present invention;

[0045] Figure 2 It is a framework diagram of a high-temperature flue gas purification device provided by an embodiment of the present invention. Detailed Embodiments

[0046] To further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following specifically describes, with reference to the accompanying drawings and preferred embodiments, a high-temperature flue gas purification method and system according to the present invention, including its specific implementation manner, structure, features, and effects. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this invention belongs.

[0048] The following specifically describes the specific solution of a high-temperature flue gas purification method and system provided by the present invention with reference to the accompanying drawings.

[0049] Please refer to Figure 1 , which shows a flowchart of a high-temperature flue gas purification method provided by an embodiment of the present invention. The method includes:

[0050] Step S1: Obtain the flue gas temperatures at the inlet and outlet of the independent cooling channel section, as well as the flue gas temperatures and humidity at the inlet and outlet of the mixed cooling channel section at the current moment. At the same time, obtain the outside air temperature and air intake volume in the air inlet channel that is interconnected with the mixed cooling channel section.

[0051] In the embodiment of the present invention, an independent cooling channel section is first deployed at a position 1-2 meters downstream of the inlet of the high-temperature flue gas pipeline. A nozzle is installed in the independent cooling channel section, and a high-temperature resistant two-fluid nozzle can be selected. The independent cooling channel section cools the flue gas in the pipeline by spraying atomized water into the flue gas using the nozzle. Then, a mixed cooling channel section is deployed at a position 3-5 meters downstream of the inlet of the high-temperature flue gas pipeline. The mixed cooling channel section is interconnected with the air inlet channel. A cold air blower and a nozzle are installed in the air inlet channel. The air inlet channel introduces outside cold air using the cold air blower, and at the same time, introduces atomized water into the outside cold air using the nozzle. Then, the outside cold air containing atomized water enters the mixed cooling channel section and cools the high-temperature flue gas in the mixed cooling channel section again. Since atomized water is introduced into the flue gas, the moisture content in the flue gas is relatively large. Therefore, a dehydration link is also deployed in the flue gas pipeline in the embodiment of the present invention to dry and dehydrate the flue gas and improve the subsequent flue gas purification effect. Please refer to Figure 2 , which shows a framework diagram of a high-temperature flue gas purification device provided by an embodiment of the present invention.

[0052] In order to improve the cooling effect of high-temperature flue gas in the pipeline, it is necessary to adjust the water injection volume of the nozzle and the air intake volume of the cooling fan based on the temperature change of the flue gas. Therefore, in the embodiments of the present invention, temperature sensors are first installed at the inlet and outlet of the independent cooling channel section respectively, and the temperature sensors are used to collect the flue gas temperatures at the inlet and outlet of the independent cooling channel section in real time. Then, temperature sensors and humidity sensors are installed at the inlet and outlet of the mixed cooling channel section respectively, and the temperature sensors and humidity sensors are used to collect the flue gas temperature and flue gas humidity at the inlet and outlet of the independent cooling channel section in real time. At the same time, temperature sensors and air flow meters are also installed at the inlet of the air intake channel, and the temperature sensors and air flow meters are used to collect the outside air temperature and air intake volume in the air intake channel in real time.

[0053] Step S2: Adjust the water injection volume of the independent cooling channel section according to the flue gas temperatures at the inlet and outlet of the independent cooling channel section to obtain the real-time water injection volume of the independent cooling channel section; based on the real-time water injection volume, cool the flue gas in the independent cooling channel section to obtain the initially cooled flue gas.

[0054] When the flue gas generated in the high-temperature furnace first enters the pipeline, the temperature of the flue gas is relatively high, usually reaching above 500 degrees Celsius or even higher. At this time, atomized water is introduced into the flue gas through the nozzle of the independent cooling channel section, which has the most direct cooling effect on the high-temperature flue gas and can quickly cool the high-temperature flue gas. At this time, the water injection volume of the nozzle and the cooling effect of the high-temperature flue gas can be considered to be positively correlated, that is, the higher the water injection volume, the better the cooling effect on the high-temperature flue gas, and the more obvious the temperature drop of the high-temperature flue gas. Therefore, in the embodiments of the present invention, the water injection volume of the independent cooling channel section is first adjusted according to the flue gas temperatures at the inlet and outlet of the independent cooling channel section to obtain the real-time water injection volume of the independent cooling channel section. Subsequently, based on the real-time water injection volume and using the nozzle in the independent cooling channel section, the flue gas can be quickly cooled.

[0055] Preferably, in an embodiment of the present invention, the method for obtaining the real-time water injection volume of the independent cooling channel section specifically includes:

[0056] Take the flue gas temperature at the inlet of the independent cooling channel section as the numerator, take the preset parameter as the denominator, and take the ratio as the flue gas temperature proportion value at the inlet of the independent cooling channel section. Take the product value of the preset water injection volume of the nozzle of the independent cooling channel section and the flue gas temperature proportion value at the inlet of the independent cooling channel section as the initial water injection volume of the independent cooling channel section.

[0057] Since the function of the independent cooling channel section is to rapidly cool the flue gas so that the temperature of the high-temperature flue gas can drop below the preset first high-temperature threshold, the difference between the flue gas temperature at the outlet of the independent cooling channel section and the preset first high-temperature threshold can be used as the temperature deviation value at the outlet of the independent cooling channel section, and the product value of the preset first feedback adjustment coefficient and the temperature deviation value can be used as the water spray adjustment amount for the independent cooling channel section. Among them, the value range of the preset first high-temperature threshold is usually 500 to 800 degrees Celsius. In an embodiment of the present invention, the preset first high-temperature threshold is set to 500 degrees Celsius. The specific value of the preset first high-temperature threshold can also be set by the implementer according to the specific implementation scenario and is not limited herein.

[0058] Furthermore, the sum value of the initial water spray amount and the water spray adjustment amount is used as the real-time water spray amount of the independent cooling channel section, realizing the feedback adjustment of the initial water spray amount of the independent cooling channel section, and ensuring that the water spray amount of the independent cooling channel section can effectively reduce the temperature of the flue gas therein below the preset first high-temperature threshold.

[0059] As an example, in an embodiment of the present invention, the expression of the real-time water spray amount of the independent cooling channel section can be specifically, for example:

[0060]

[0061]

[0062]

[0063] Among them, represents the real-time water spray amount of the independent cooling channel section; represents the initial water spray amount of the independent cooling channel section; represents the water spray adjustment amount of the independent cooling channel section; represents the preset water spray amount of the nozzle of the independent cooling channel section, and its value range is usually 1 to 10 cubic meters per hour. In an embodiment of the present invention, is set to 3, The specific value of can also be set by the implementer according to the specific implementation scenario and is not limited herein; represents the flue gas temperature at the inlet of the independent cooling channel section; represents a preset parameter used to narrow the value, The value range of is 1000 to 1200. In an embodiment of the present invention, is set to 1000, The specific value of can also be set by the implementer according to the specific implementation scenario and is not limited herein; The proportional value of the flue gas temperature representing the inlet of the independent cooling channel section; The flue gas temperature representing the outlet of the independent cooling channel section; Represents a preset first high temperature threshold; Represents the temperature deviation value at the outlet of the independent cooling channel section; Represents a preset first feedback adjustment coefficient. In an embodiment of the present invention, is set to 0.3, The specific value of can also be set by the implementer according to the specific implementation scenario and is not limited herein.

[0064] After determining the real-time water injection volume of the independent cooling channel section, based on the real-time water injection volume, the flue gas in the independent cooling channel section can be cooled for the first time to obtain the initially cooled flue gas.

[0065] Preferably, in an embodiment of the present invention, the method for obtaining the initially cooled flue gas specifically includes:

[0066] Since nozzles are installed in the independent cooling channel section, the nozzles in the independent cooling channel section can be used to spray and water-cool the flue gas in the independent cooling channel section with the real-time water injection volume to obtain the initially cooled flue gas. This process can be achieved by, for example, adjusting the operating power of the nozzles or the opening and closing degree of the valves through a PLC control system to control the water injection volume of the nozzles.

[0067] Thus, the first cooling treatment of the high-temperature flue gas is achieved.

[0068] Step S3: Obtain the initial atomized water content and the initial air intake volume of the air intake channel according to the flue gas temperature and humidity at the inlet of the mixed cooling channel section, as well as the outside air temperature and air intake volume in the air intake channel; adjust the initial atomized water content and the initial air intake volume according to the flue gas temperature and humidity at the outlet of the mixed cooling channel section to obtain the final atomized water content and the final air intake volume of the air intake channel; based on the final atomized water content and the final air intake volume, cool the initially cooled flue gas in the mixed cooling channel section to obtain the finally cooled flue gas.

[0069] After the flue gas in the pipeline is cooled for the first time to obtain the initially cooled flue gas, then the initially cooled flue gas continues to move forward in the pipeline and enters the mixed cooling channel section. At this time, although the temperature of the initially cooled flue gas has been greatly reduced, its temperature is still relatively high, which is not conducive to subsequent purification treatment. Therefore, it is necessary to cool the initially cooled flue gas again. When performing the second cooling treatment, if only the method of introducing atomized water into the initially cooled flue gas using a nozzle is used for cooling, it will cause the humidity in the flue gas to be too high, resulting in filter bag caking or pipeline corrosion. And if only the method of introducing external cold air into the initially cooled flue gas is used for cooling, since the cooling effect of the external cold air on the initially cooled flue gas is not obvious, a large amount of external air needs to be introduced, increasing the workload. Therefore, in the embodiment of the present invention, by deploying the mixed cooling channel section, by mixing the external cold air and the atomized water, the external cold air containing atomized water is introduced into the initially cooled flue gas to effectively cool the initially cooled flue gas.

[0070] Since the initially cooled flue gas has undergone a cooling treatment before, its temperature is lower than before. When using atomized water for cooling, the utilization efficiency of the atomized water by the initially cooled flue gas with a relatively lower temperature is also lower. Therefore, in the mixed cooling channel section, in order to prevent the humidity of the flue gas after the second cooling from being too high, and at the same time to ensure that the temperature of the initially cooled flue gas can be reduced to a reasonable range after the second cooling, it is necessary to accurately control the content of atomized water in the external cold air and the intake air volume of the external cold air in the air intake channel. Therefore, in the embodiment of the present invention, first, according to the flue gas temperature and flue gas humidity at the inlet of the mixed cooling channel section, as well as the external air temperature and intake air volume in the air intake channel, the initial atomized water content and the initial intake air volume of the air intake channel are initially obtained. Among them, the initial intake air volume of the air intake channel represents the intake air volume required for cooling the initially cooled flue gas in the mixed cooling channel section, and the initial atomized water content represents the content of atomized water required to be contained in the external cold air for cooling the initially cooled flue gas in the mixed cooling channel section. Subsequently, the initial atomized water content and the initial intake air volume of the air intake channel can be further adjusted to ensure the cooling effect on the flue gas.

[0071] Preferably, in an embodiment of the present invention, the method for obtaining the initial atomized water content and the initial intake air volume of the air intake channel specifically includes:

[0072] First, since different atomized water contents have different cooling effects on high-temperature flue gas, and there is an optimal atomized water content for flue gas at a certain temperature, the flue gas temperature at the inlet of the mixed cooling channel section can be input into the optimal atomized water content model, and the optimal atomized water content of the mixed cooling channel section is output by the optimal atomized water content model.

[0073] It should be noted that the optimal atomized water content model is a function. The independent variable is the flue gas temperature, and the dependent variable is the optimal atomized water content in the mixed cooling channel section. This model can be obtained through the experimental process. The general experimental process is as follows: First, heat the flue gas used in the experiment to a certain temperature, such as 500 degrees Celsius. Then, set multiple groups of experiments at this temperature. In different groups of experiments, inject different amounts of atomized water into the flue gas at this temperature. After each group of experiments is completed, measure the temperature and humidity of the flue gas, and use the difference in the temperature of the flue gas before and after cooling as the numerator, and the humidity of the flue gas after cooling as the denominator. The ratio is used as the evaluation value for each group. The larger the evaluation value of a certain group of experiments, the more it indicates that the atomized water content corresponding to this group of experiments is the optimal atomized water content at this temperature. Then, heat the flue gas to different temperatures and perform the above experimental process on the flue gas at different temperatures, so as to obtain the optimal atomized water content at different temperatures, and perform curve fitting on the optimal atomized water content at different temperatures to obtain the corresponding function, that is, the optimal atomized water content model. Among them, the method of curve fitting can choose the least squares method or other methods, which is not limited here.

[0074] Take the sum of the air intake in the air inlet channel and the flue gas intake in the pipeline as the comprehensive gas volume in the mixed cooling channel section, and take the product value of the optimal atomized water content and the comprehensive gas volume as the optimal water volume in the mixed cooling channel section.

[0075] Take the product value of the flue gas intake in the pipeline and the flue gas humidity at the inlet of the mixed cooling channel section as the flue gas water volume at the inlet of the mixed cooling channel section.

[0076] Take the difference between the optimal water volume and the flue gas water volume as the numerator, and the air intake in the air inlet channel as the denominator. The ratio is used as the initial atomized water content in the air inlet channel. It should be noted that the initial atomized water content refers to the atomized water content in the outside air in the air inlet channel.

[0077] As an example, in an embodiment of the present invention, the expression of the initial atomized water content in the air inlet channel can be specifically, for example:

[0078]

[0079] Among them, represents the initial atomized water content in the air inlet channel; represents the optimal atomized water content in the mixed cooling channel section; represents the air intake in the air inlet channel; represents the flue gas intake in the pipeline, is a known fixed value in a specific scenario, and its value varies in different scenarios; represents the comprehensive gas volume in the mixed cooling channel section; Represents the optimal moisture content of the mixed cooling channel section; Represents the flue gas humidity at the inlet of the mixed cooling channel section; Represents the moisture content of the flue gas at the inlet of the combined cooling channel section.

[0080] Among them, this formula is obtained by transforming the equation This equation indicates that the sum of the moisture content required in the outside air and the moisture content of the flue gas at the inlet of the mixed cooling channel section is equal to the optimal moisture content corresponding to the mixed gas formed by the flue gas and the outside air in the mixed cooling channel section, so as to ensure that the atomized water content in the outside air can achieve the best cooling effect on the initial cooling flue gas in the mixed cooling channel section.

[0081] Then, analyze the initial air intake volume of the air inlet channel. Based on the flue gas temperature at the inlet of the mixed cooling channel section, the outside air temperature in the air inlet channel, the intake volume of the flue gas in the pipeline, and the initial atomized water content in the mixed cooling channel section, obtain the initial air intake volume of the air inlet channel.

[0082] Preferably, in an embodiment of the present invention, the method for obtaining the initial air intake volume of the air inlet channel further includes:

[0083] Based on the calculation formula for the initial air intake volume of the air inlet channel, obtain the initial air intake volume of the air inlet channel. The calculation formula for the initial air intake volume of the mixed cooling channel section is:

[0084]

[0085] Among them, Represents the initial air intake volume of the air inlet channel; Represents the intake volume of the flue gas in the pipeline; Represents the density of the flue gas in the pipeline, usually 0.6; Represents the specific heat capacity of the flue gas in the pipeline, usually 1.2; Represents the flue gas temperature at the inlet of the mixed cooling channel section; Represents the preset second high temperature threshold. Since the purpose of deploying the mixed cooling channel section is to reduce the temperature of the flue gas below the preset second high temperature threshold, it is necessary to set , The value range of is usually 200 - 400 degrees Celsius. In an embodiment of the present invention, is set to 200 degrees Celsius. The specific value of can also be set by the implementer according to the specific implementation scenario and is not limited herein; Represents the density of the outside air in the air inlet channel, usually 1.2; Represents the specific heat capacity of the outside air in the air inlet channel, usually 1.005; ​Represents the initial atomized water content of the air inlet channel; Represents the specific heat capacity of water, usually 4.2; Represents the outside air temperature in the air inlet channel.

[0086] Among them, this formula is obtained by transforming the equation This equation represents that the heat absorbed by the outside air and the atomized water is equal to the heat lost by the flue gas in the mixed cooling channel section.

[0087] Since in the above-mentioned feed-forward regulation, some parameters use fixed values under ideal conditions, there will inevitably be deviations in the actual situation. In order to carry out more refined control of the feed-forward regulation, it is also necessary to perform feedback regulation to improve the accuracy of high-temperature flue gas cooling.

[0088] When the initial atomized water content in the feed-forward regulation is too large, the atomized water in the mixed cooling section is not completely consumed. In the long run, too much atomized water content will accumulate in the mixed cooling channel section, resulting in an increase in the atomized water content at the outlet of the mixed cooling section and a too low temperature of the flue gas after cooling; when the initial atomized water content in the feed-forward regulation is too small, the atomized water in the mixed cooling channel section is quickly consumed, and the atomized water content at the outlet decreases, resulting in a too high temperature of the flue gas after cooling.

[0089] When the initial air intake in the feed-forward regulation is too small, it will cause the cooling effect in the mixed cooling channel section to overly rely on the atomized water in the outside air. However, since the cooling effect of the atomized water on the initially cooled flue gas with a lower temperature is limited, it will result in a relatively sufficient atomized water content at the outlet of the mixed cooling channel section, but the temperature of the flue gas after cooling will be relatively too high. On the contrary, when the initial air intake in the feed-forward regulation is too large, it will cause the atomized water content at the outlet of the mixed cooling channel section to decrease, and the temperature of the flue gas after cooling will be relatively too low. Therefore, the initial atomized water content and the initial air intake can be adjusted according to the flue gas temperature and flue gas humidity at the outlet of the mixed cooling channel section to obtain the final atomized water content and the final air intake of the air inlet channel. Subsequently, based on the final atomized water content and the final air intake, the initially cooled flue gas in the mixed cooling channel section can be cooled again, so that the temperature of the high-temperature flue gas is reduced to a reasonable range, improving the subsequent effect of flue gas purification.

[0090] Preferably, in an embodiment of the present invention, the method for obtaining the final atomized water content and the final air intake of the air inlet channel specifically includes:

[0091] Taking the difference between the flue gas temperature at the outlet of the mixed cooling channel section and the preset second high-temperature threshold as the numerator, taking the preset second high-temperature threshold as the denominator, and taking the ratio as the temperature performance value at the outlet of the mixed cooling channel section.

[0092] Take the difference between the flue gas humidity at the outlet of the mixed cooling channel section and the preset humidity threshold as the numerator, and the preset humidity threshold as the denominator, and use the ratio as the humidity accumulation amount at the outlet of the mixed cooling channel section.

[0093] Obtain the atomized water adjustment amount and the air intake adjustment amount of the air intake channel according to the temperature performance value and the humidity accumulation amount at the outlet of the mixed cooling channel section.

[0094] Preferably, in an embodiment of the present invention, the method for obtaining the atomized water adjustment amount and the air intake adjustment amount of the air intake channel specifically includes:

[0095] Based on the calculation formulas for the atomized water adjustment amount and the air intake adjustment amount of the air intake channel, obtain the atomized water adjustment amount and the air intake adjustment amount of the air intake channel. The calculation formulas for the atomized water adjustment amount and the air intake adjustment amount of the air intake channel are:

[0096]

[0097]

[0098]

[0099]

[0100] Wherein, represents the air intake adjustment amount of the air intake channel; represents the atomized water adjustment amount of the air intake channel; represents a preset second feedback adjustment coefficient. In an embodiment of the present invention, is set to 0.05, The specific value of can also be set by the implementer according to the specific implementation scenario and is not limited here; represents the humidity accumulation amount at the outlet of the mixed cooling channel section; represents the temperature performance value at the outlet of the mixed cooling channel section; represents a preset adjustment parameter; represents an activation function; represents the flue gas temperature at the outlet of the mixed cooling channel section; represents a preset second high temperature threshold; represents the flue gas humidity at the outlet of the mixed cooling channel section; represents a preset humidity threshold. In an embodiment of the present invention, is set to 0.08, The specific value of can also be set by the implementer according to the specific real-time scenario and is not limited here.

[0101] Furthermore, the sum of the initial atomized water content and the atomized water adjustment amount of the air inlet passage can be used as the final atomized water content of the air inlet passage, and the sum of the initial air inlet volume and the air inlet adjustment amount of the air inlet passage can be used as the final air inlet volume of the air inlet passage, so as to realize the feedback adjustment of the initial atomized water content and the initial air inlet volume of the air inlet passage.

[0102] As an example, in an embodiment of the present invention, the expressions of the final atomized water content and the final air inlet volume of the air inlet passage can be specifically, for example:

[0103]

[0104]

[0105] Among them, represents the final atomized water content of the air inlet passage; represents the final air inlet volume of the air inlet passage; represents the initial atomized water content of the air inlet passage; represents the atomized water adjustment amount of the air inlet passage; represents the initial air inlet volume of the air inlet passage; represents the air inlet adjustment amount of the air inlet passage.

[0106] After determining the final atomized water content and the final air inlet volume of the air inlet passage, the initial cooling flue gas in the mixed cooling passage section can be cooled again based on the final atomized water content and the final air inlet volume, so as to obtain the final cooling flue gas, making the temperature of the final cooling flue gas more suitable for subsequent flue gas purification treatment.

[0107] Preferably, in an embodiment of the present invention, the method for obtaining the final cooling flue gas specifically includes:

[0108] For example, a PLC control system can be used to adjust the operating power of the cooling fan and the nozzle in the air inlet passage, so that the air inlet volume of the cooling fan is the final air inlet volume, and at the same time, the water content in the outside air in the air inlet passage is the final atomized water content. Mix the water ejected from the nozzle with the outside air, and use the outside air containing water to cool the initial cooling flue gas in the mixed cooling passage section to obtain the final cooling flue gas.

[0109] Thus, the second cooling treatment of the flue gas is realized.

[0110] Step S4: Purify the final cooling flue gas.

[0111] After the above-mentioned continuous two-stage cooling treatment of the high-temperature flue gas, the temperature of the high-temperature flue gas drops to a reasonable range. Furthermore, the final cooling flue gas can be purified to improve the final purification effect.

[0112] Preferably, in an embodiment of the present invention, the method for purifying the finally cooled flue gas specifically includes:

[0113] First, dehydrate the finally cooled flue gas to obtain the dehydrated finally cooled flue gas, and then sequentially introduce the dehydrated finally cooled flue gas into a dust collector, a desulfurization tower, and a denitration reactor for purification treatment. After the flue gas passes the emission standard after purification treatment, it can be discharged into the atmosphere through a chimney.

[0114] An embodiment of the present invention provides a high-temperature flue gas purification system, which includes a memory, a processor, and a computer program. The memory is used to store the corresponding computer program, and the processor is used to run the corresponding computer program. When the computer program runs in the processor, it can implement the method described in steps S1 to S4.

[0115] It should be noted that the above sequence of embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0116] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments can be referred to each other, and the key points of each embodiment are the differences from other embodiments.

Claims

1. A high-temperature flue gas purification method, characterized in that, The method includes: Obtaining the flue gas temperatures at the inlet and outlet of the independent cooling channel section and the flue gas temperatures and flue gas humidity at the inlet and outlet of the mixed cooling channel section at the current moment, and simultaneously obtaining the outside air temperature and air intake in the air inlet channel communicating with the mixed cooling channel section; Adjusting the water injection amount of the independent cooling channel section according to the flue gas temperatures at the inlet and outlet of the independent cooling channel section to obtain the real-time water injection amount of the independent cooling channel section; based on the real-time water injection amount, cooling the flue gas in the independent cooling channel section to obtain initially cooled flue gas; Obtaining the initial atomized water content and initial air intake of the air inlet channel according to the flue gas temperature and flue gas humidity at the inlet of the mixed cooling channel section, as well as the outside air temperature and air intake in the air inlet channel; adjusting the initial atomized water content and initial air intake according to the flue gas temperature and flue gas humidity at the outlet of the mixed cooling channel section to obtain the final atomized water content and final air intake of the air inlet channel; based on the final atomized water content and final air intake, cooling the initially cooled flue gas in the mixed cooling channel section to obtain finally cooled flue gas; Performing purification treatment on the finally cooled flue gas; The obtaining of the initial atomized water content and initial air intake of the air inlet channel includes: Inputting the flue gas temperature at the inlet of the mixed cooling channel section into the optimal atomized water content model, and the optimal atomized water content model outputs the optimal atomized water content of the mixed cooling channel section, and the optimal atomized water content model is a fitting function obtained by curve fitting of the optimal atomized water content at different temperatures; Taking the sum value of the air intake in the air inlet channel and the intake of flue gas in the pipeline as the comprehensive gas volume of the mixed cooling channel section; taking the product value of the optimal atomized water content and the comprehensive gas volume as the optimal water content of the mixed cooling channel section; Taking the product value of the intake of flue gas in the pipeline and the flue gas humidity at the inlet of the mixed cooling channel section as the flue gas water content at the inlet of the mixed cooling channel section; Taking the difference between the optimal water content and the flue gas water content as the numerator, taking the air intake in the air inlet channel as the denominator, and taking the ratio as the initial atomized water content of the air inlet channel; Obtaining the initial air intake of the air inlet channel according to the flue gas temperature at the inlet of the mixed cooling channel section, the outside air temperature in the air inlet channel, the intake of flue gas in the pipeline, and the initial atomized water content of the mixed cooling channel section; The obtaining of the initial air intake of the air inlet channel includes: Based on the calculation formula for the initial air intake of the air inlet channel, obtaining the initial air intake of the air inlet channel, and the calculation formula for the initial air intake of the mixed cooling channel section is: Among them, represents the initial air intake of the air inlet passage; represents the intake of flue gas in the pipeline; represents the density of the flue gas in the pipeline; represents the specific heat capacity of the flue gas in the pipeline; represents the flue gas temperature at the inlet of the mixed cooling channel section; represents the preset second high temperature threshold; represents the density of the outside air in the air inlet passage; represents the specific heat capacity of the outside air in the air inlet passage; represents the initial atomized water content of the air inlet passage; represents the specific heat capacity of water; represents the outside air temperature in the air inlet passage; The obtaining of the final atomized water content and final air intake of the air inlet channel includes: Taking the difference between the flue gas temperature at the outlet of the mixed cooling channel section and the preset second high temperature threshold as the numerator, taking the preset second high temperature threshold as the denominator, and taking the ratio as the temperature performance value at the outlet of the mixed cooling channel section; Taking the difference between the flue gas humidity at the outlet of the mixed cooling channel section and the preset humidity threshold as the numerator, taking the preset humidity threshold as the denominator, and taking the ratio as the humidity cumulative amount at the outlet of the mixed cooling channel section; Obtain the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage according to the temperature performance value and the humidity accumulation amount at the outlet of the mixed cooling passage section; Use the sum value of the initial atomized water content and the atomized water adjustment amount of the air inlet passage as the final atomized water content of the air inlet passage, and use the sum value of the initial air intake amount and the air intake adjustment amount of the air inlet passage as the final air intake amount of the air inlet passage; The obtaining of the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage includes: Based on the calculation formulas of the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage, obtain the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage. The calculation formulas of the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage are: Among them, represents the air intake regulation amount of the air intake passage; represents the atomized water regulation amount of the air intake passage; represents the preset second feedback regulation coefficient; represents the humidity accumulation amount at the outlet of the mixed cooling passage section; represents the temperature performance value at the outlet of the mixed cooling passage section; represents the preset regulation parameter; represents the activation function.

2. The high-temperature flue gas purification method according to claim 1, characterized in that The obtaining of the real-time water spraying amount of the independent cooling passage section includes: Use the flue gas temperature at the inlet of the independent cooling passage section as the numerator, use the preset parameter as the denominator, and use the ratio as the flue gas temperature ratio value at the inlet of the independent cooling passage section; use the product value of the preset water spraying amount of the nozzle of the independent cooling passage section and the flue gas temperature ratio value at the inlet of the independent cooling passage section as the initial water spraying amount of the independent cooling passage section; Use the difference between the flue gas temperature at the outlet of the independent cooling passage section and the preset first high temperature threshold as the temperature deviation value at the outlet of the independent cooling passage section; use the product value of the preset first feedback adjustment coefficient and the temperature deviation value as the water spraying adjustment amount of the independent cooling passage section; Use the sum value of the initial water spraying amount and the water spraying adjustment amount as the real-time water spraying amount of the independent cooling passage section.

3. A high-temperature flue gas purification method according to claim 1, characterized in that, The obtaining of the initial cooled flue gas includes: Use the nozzles in the independent cooling passage section to spray water-cool the flue gas in the independent cooling passage section with the real-time water spraying amount to obtain the initial cooled flue gas.

4. A high-temperature flue gas purification method according to claim 1, characterized in that, The obtaining of the final cooled flue gas includes: Adjust the operating power of the cooling fan and the nozzles in the air inlet passage so that the air intake of the cooling fan is the final air intake amount, and at the same time make the content of moisture in the outside air in the air inlet passage be the final atomized water content. Mix the moisture sprayed by the nozzles with the outside air, and use the outside air containing moisture to cool the initial cooled flue gas in the mixed cooling passage section to obtain the final cooled flue gas.

5. A high-temperature flue gas purification method according to claim 1, characterized in that, The purification treatment of the final cooled flue gas includes: Perform dehydration treatment on the final cooled flue gas to obtain the dehydrated final cooled flue gas, and sequentially pass the dehydrated final cooled flue gas into a dust collector, a desulfurization tower and a denitrification reactor for purification treatment.

6. A high-temperature flue gas purification system, the system comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 5.

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