High-temperature flue gas purification method and system

Abstract

The invention relates to the field of flue gas purification, in particular to a high-temperature flue gas purification method and system. The method comprises the following steps: firstly, acquiring the flue gas temperatures of an inlet and an outlet of an independent cooling channel section at the current moment, and the flue gas temperatures and the flue gas humidity of an inlet and an outlet of a mixed cooling channel section, and acquiring the external air temperature and the air inlet amount in an air inlet channel communicated with the mixed cooling channel section at the same time; the water spraying amount of the independent cooling channel section is adjusted, the flue gas in the independent cooling channel section is cooled for the first time on the basis of the obtained real-time water spraying amount, the flue gas in the mixed cooling channel section is cooled again on the basis of the obtained final atomized water content and final air inlet amount, and finally cooled flue gas is obtained; and finally, the cooled flue gas is purified. According to the invention, the temperature of the high-temperature flue gas can be effectively reduced to a reasonable range, and the purification effect on the high-temperature flue gas is improved.

Description

Technical Field

[0001] The present invention relates to the field of flue gas purification, and specifically relates to a method and system for purifying high-temperature flue gas. 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, affected by factors such as fuel, combustion efficiency, and combustion temperature requirements, there will be significant differences in the temperature of the discharged high-temperature flue gas. 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 significantly 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 high-temperature flue gas and reduce the purification effect of high-temperature flue gas, the purpose of the present invention is to provide a method and system for purifying high-temperature flue gas, and the specific technical solutions adopted are as follows: The present invention proposes a method for purifying high-temperature flue gas, and the method includes: 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 inlet channel communicating with the mixed cooling channel section; 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 down the flue gas in the independent cooling channel section to obtain the initially cooled flue gas; Obtain the initial atomized water content and the initial air intake of the air inlet channel according to the flue gas temperature and the flue gas humidity at the inlet of the mixed cooling channel section, as well as the outside air temperature and the air intake in the air inlet channel; 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 channel section to obtain the final atomized water content and the final air intake of the air inlet channel; based on the final atomized water content and the final air intake, cool the initial cooled flue gas in the mixed cooling channel section to obtain the final cooled flue gas; Carry out purification treatment on the final cooled flue gas.

[0005] Further, the obtaining of the real-time water spray amount of the independent cooling channel section includes: Use the flue gas temperature at the inlet of the independent cooling channel 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 channel section; use the product value of the preset water spray amount of the nozzle of the independent cooling channel section and the flue gas temperature ratio value at the inlet of the independent cooling channel section as the initial water spray amount of the independent cooling channel section; Use the difference between the flue gas temperature at the outlet of the independent cooling channel section and the preset first high temperature threshold as the temperature deviation value at the outlet of the independent cooling channel 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 channel section; 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 channel section.

[0006] Further, the obtaining of the initial cooled flue gas includes: Use the nozzle in the independent cooling channel section to spray and water-cool the flue gas in the independent cooling channel section with the real-time water spray amount to obtain the initial cooled flue gas.

[0007] Further, the obtaining of the initial atomized water content and the initial air intake of the air inlet channel includes: Input 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 of the mixed cooling channel section is output by the optimal atomized water content model; Use the sum value of the air intake in the air inlet channel and the air intake of the flue gas in the pipeline as the comprehensive gas volume of the mixed cooling channel 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 channel section; Use the product value of the air intake of the 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; Use the difference between the optimal water content and the flue gas water content as the numerator, use the air intake in the air inlet channel as the denominator, and use the ratio as the initial atomized water content of the air inlet channel; Obtain the initial air intake of the air inlet passage based on the flue gas temperature at the inlet of the mixed cooling passage section, the outside air temperature in the air inlet passage, the intake air volume of the flue gas in the pipeline, and the initial atomized water content of the mixed cooling passage section.

[0008] Further, the obtaining of the initial air intake of the air inlet passage includes: Based on the calculation formula for the initial air intake of the air inlet passage, obtain the initial air intake of the air inlet passage. The calculation formula for the initial air intake of the mixed cooling passage section is: Wherein, represents the initial air intake of the air inlet passage; 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 passage 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.

[0009] Further, the obtaining of the final atomized water content and the final air intake of the air inlet passage includes: Use the difference between the flue gas temperature at the outlet of the mixed cooling passage section and the preset second high temperature threshold as the numerator, and the preset second high temperature threshold as the denominator, and use the ratio as the temperature performance value at the outlet of the mixed cooling passage section; Use the difference between the flue gas humidity at the outlet of the mixed cooling passage section and the preset humidity threshold as the numerator, and the preset humidity threshold as the denominator, and use the ratio as the humidity cumulative amount at the outlet of the mixed cooling passage section; According to the temperature performance value and the humidity cumulative amount at the outlet of the mixed cooling passage section, obtain the atomized water adjustment amount and the air intake adjustment amount of the air inlet passage; Use the sum 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 of the initial air intake and the air intake adjustment amount of the air inlet passage as the final air intake of the air inlet passage.

[0010] Further, 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 for the atomized water adjustment amount and the air intake adjustment amount of the air intake passage, the atomized water adjustment amount and the air intake adjustment amount of the air intake passage are obtained. The calculation formulas for the atomized water adjustment amount and the air intake adjustment amount of the air intake passage are as follows: Among them, represents the air intake adjustment amount of the air intake passage; represents the atomized water adjustment amount of the air intake passage; represents a preset second feedback adjustment coefficient; represents the cumulative humidity 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.

[0011] Further, the obtaining of the finally cooled flue gas includes: Adjust the operating power of the cooling fan and the nozzle in the air intake 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 intake passage 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.

[0012] Further, the purification treatment of the finally cooled flue gas includes: 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 into a dust collector, a desulfurization tower, and a denitrification reactor for purification treatment.

[0013] The present invention also proposes a high-temperature flue gas purification system, which includes a memory, a processor, and a computer program stored in the memory and operable 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.

[0014] The present invention has the following beneficial effects: Considering that the existing methods cannot effectively cool high-temperature flue gas and reduce the purification effect of high-temperature flue gas, this 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. At the same time, it obtains the outside air temperature and the air intake volume in the air inlet channel interconnected with the mixed cooling channel section. Subsequently, based on this data and by combining two methods of introducing outside cold air and atomized water, it can effectively cool the high-temperature flue gas in the pipeline. Since the temperature of the flue gas in the pipeline is relatively high before cooling treatment, first, through the obtained real-time water spraying 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 drop rapidly. 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. By reasonably allocating the usage amounts of atomized water and outside cold air, while 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 the high-temperature flue gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] 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 drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0016] Figure 1 It is a flowchart of a method for purifying high-temperature flue gas provided by an embodiment of the present invention; Figure 2 It is a framework diagram of a high-temperature flue gas purification device provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] In order to further elaborate on the technical means and effects adopted by the present invention to achieve the intended invention purpose, the following, in combination with the drawings and preferred embodiments, details the specific implementation manners, structures, features, and effects of a method and system for purifying high-temperature flue gas proposed according to the present invention. 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.

[0018] 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 the present invention belongs.

[0019] The following specifically describes the specific solutions of a high-temperature flue gas purification method and system provided by the present invention in conjunction with the accompanying drawings.

[0020] 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: Step S1: 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. At the same time, obtain the outside air temperature and the air intake volume in the air inlet channel that is interconnected with the mixed cooling channel section.

[0021] In the embodiment of the present invention, an independent cooling channel section is first deployed at 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 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 cooling fan and a nozzle are installed in the air inlet channel. The air inlet channel introduces outside cold air using the cooling fan, 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, in the embodiment of the present invention, a dehydration link is also deployed in the flue gas pipeline to dry and dehydrate the flue gas and improve the subsequent purification effect of the flue gas. 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.

[0022] To improve the cooling effect of the high-temperature flue gas in the pipeline, it is necessary to adjust the water spraying amount of the nozzle and the air intake volume of the cooling fan based on the temperature change of the flue gas. Therefore, in the embodiment 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 temperatures 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 inlet channel, and the temperature sensors and air flow meters are used to collect the outside air temperature and the air intake volume in the air inlet channel in real time.

[0023] 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 down the flue gas in the independent cooling channel section to obtain the initially cooled-down flue gas.

[0024] 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 nozzles of the independent cooling channel section, which has the most direct cooling effect on the high-temperature flue gas and can quickly cool down the high-temperature flue gas. At this time, the water injection volume of the nozzles and the cooling effect on 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, first, the water injection volume of the independent cooling channel section is 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 nozzles in the independent cooling channel section, the flue gas can be quickly cooled down.

[0025] 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: Use the flue gas temperature at the inlet of the independent cooling channel section as the numerator, the preset parameter as the denominator, and the ratio as the flue gas temperature proportion value at the inlet of the independent cooling channel section. Multiply the preset water injection volume of the nozzles in the independent cooling channel section by the flue gas temperature proportion value at the inlet of the independent cooling channel section to obtain the initial water injection volume of the independent cooling channel section.

[0026] Since the function of the independent cooling channel section is to quickly cool down 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 injection adjustment volume of the independent cooling channel section. Among them, the value range of the preset first high-temperature threshold is usually 500 - 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.

[0027] Furthermore, the sum value of the initial water injection volume and the water injection adjustment volume is used as the real-time water injection volume of the independent cooling channel section to realize the feedback adjustment of the initial water injection volume of the independent cooling channel section, ensuring that the water injection volume of the independent cooling channel section can effectively reduce the temperature of the flue gas therein to below the preset first high-temperature threshold.

[0028] As an example, in an embodiment of the present invention, the expression for the real-time water spray volume of the independent cooling channel section can be specifically, for example: Wherein, represents the real-time water spray volume of the independent cooling channel section; represents the initial water spray volume of the independent cooling channel section; represents the water spray adjustment volume of the independent cooling channel section; represents the preset water spray volume 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 for narrowing the value of, 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; represents the flue gas temperature ratio value at the inlet of the independent cooling channel section; represents the flue gas temperature at 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.

[0029] After determining the real-time water spray volume of the independent cooling channel section, the flue gas in the independent cooling channel section can be subjected to the first cooling treatment based on the real-time water spray volume, thereby obtaining the initially cooled flue gas.

[0030] Preferably, in an embodiment of the present invention, the method for obtaining the initially cooled flue gas specifically includes: Since nozzles are installed in the independent cooling channel section, the nozzles in the independent cooling channel section can be utilized to spray water in real time to cool down the flue gas in the independent cooling channel section through spray water cooling, obtaining initially cooled flue gas. This process can be achieved by adjusting the operating power of the nozzles or the opening and closing degree of the valves through, for example, a PLC control system to control the water spray volume of the nozzles.

[0031] Thus, the first cooling treatment of the high-temperature flue gas is realized.

[0032] 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 down the initially cooled flue gas in the mixed cooling channel section to obtain the finally cooled flue gas.

[0033] After the first cooling of the flue gas in the pipeline to obtain the initially cooled flue gas, then the initially cooled flue gas continues to advance 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 down 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 by using nozzles 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 outside cold air into the initially cooled flue gas is used for cooling, since the cooling effect of the outside 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 outside cold air and the atomized water and introducing the outside cold air containing atomized water into the initially cooled flue gas, the effective cooling of the initially cooled flue gas is realized.

[0034] Since the initial cooling flue gas has undergone a cooling treatment before, its temperature is lower than before. When using atomized water for cooling, the relatively lower temperature initial cooling flue gas has a lower utilization efficiency for atomized water. Therefore, in the mixed cooling channel section, in order to prevent the humidity of the flue gas after secondary cooling from being too high, and at the same time to ensure that the temperature of the initial cooling 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 embodiments of the present invention, first, according to the flue gas temperature and 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 initial cooling flue gas in the mixed cooling channel section, and the initial atomized water content represents the content of atomized water required in the external cold air for cooling the initial cooling 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.

[0035] 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: 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. Therefore, 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.

[0036] It should be noted that the optimal atomized water content model is a function, where the independent variable is the flue gas temperature and the dependent variable is the optimal atomized water content of the mixed cooling channel section. This model can be obtained through an experimental process. The general process of the experiment 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, spray different contents 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, and use the ratio as the evaluation value for each group. The larger the evaluation value of a certain group of experiments, the more 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 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 be the least squares method or other methods, which is not limited here.

[0037] The sum of the air intake volume in the air inlet passage and the flue gas intake volume in the pipeline is used as the comprehensive gas volume of the mixed cooling passage section, and the product value of the optimal atomized water content and the comprehensive gas volume is used as the optimal water content of the mixed cooling passage section.

[0038] The product value of the flue gas intake volume in the pipeline and the flue gas humidity at the inlet of the mixed cooling passage section is used as the flue gas water content at the inlet of the mixed cooling passage section.

[0039] Taking the difference between the optimal water content and the flue gas water content as the numerator, and the air intake volume in the air inlet passage as the denominator, the ratio is used as the initial atomized water content of the air inlet passage. It should be noted that the initial atomized water content refers to the atomized water content in the outside air in the air inlet passage.

[0040] As an example, in an embodiment of the present invention, the expression of the initial atomized water content of the air inlet passage can be specifically, for example: Wherein, represents the initial atomized water content of the air inlet passage; represents the optimal atomized water content of the mixed cooling passage section; represents the air intake volume in the air inlet passage; represents the flue gas intake volume in the pipeline, is a known fixed value in a specific scenario, and has different values in different scenarios; represents the comprehensive gas volume of the mixed cooling passage section; represents the optimal water content of the mixed cooling passage section; represents the flue gas humidity at the inlet of the mixed cooling passage section; represents the flue gas water content at the inlet of the combined cooling passage section.

[0041] Among them, this formula is obtained by transforming the equation This equation means that the sum of the water content required in the outside air and the flue gas water content at the inlet of the mixed cooling passage section is equal to the optimal water content corresponding to the mixed gas formed by the flue gas and the outside air in the mixed cooling passage 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 passage section.

[0042] Then, analyze the initial air intake volume of the air inlet passage, and obtain the initial air intake volume of the air inlet passage according to the flue gas temperature at the inlet of the mixed cooling passage section, the outside air temperature in the air inlet passage, the flue gas intake volume in the pipeline, and the initial atomized water content of the mixed cooling passage section.

[0043] Preferably, in an embodiment of the present invention, the method for obtaining the initial air intake volume of the air inlet passage further includes: Based on the calculation formula of the initial air intake of the air inlet channel, the initial air intake of the air inlet channel is obtained. The calculation formula of the initial air intake of the mixed cooling channel section is as follows: Wherein, represents the initial air intake 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, 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 it here , 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 in the air inlet channel; represents the specific heat capacity of water, usually 4.2; represents the outside air temperature in the air inlet channel.

[0044] Among them, this formula is obtained by transforming the equation This equation means 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.

[0045] Since in the above feedforward regulation, some parameters use fixed values under ideal conditions, there will inevitably be deviations in the actual situation. In order to perform more refined regulation on the feedforward regulation, it is also necessary to perform feedback regulation to improve the accuracy of high-temperature flue gas cooling.

[0046] When the initial atomized water content in the feedforward regulation is too large, then 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 causing the temperature of the flue gas after cooling to be too low; when the initial atomized water content in the feedforward regulation is too small, at this time, the atomized water in the mixed cooling channel section is quickly consumed, and the atomized water content at the outlet decreases, resulting in the temperature of the flue gas after cooling being too high.

[0047] When the initial air intake in the feed-forward adjustment is too small, the temperature reduction effect in the mixed cooling channel section will overly rely on the atomized water in the outside air. However, since the temperature reduction effect of atomized water on the initially cooled flue gas with a relatively low temperature is limited, the atomized water content at the outlet of the mixed cooling channel section will be relatively sufficient, 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 adjustment is too large, the atomized water content at the outlet of the mixed cooling channel section will 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 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 can be reduced to a reasonable range, improving the subsequent flue gas purification effect.

[0048] 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: 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, and 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.

[0049] 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, and taking the preset humidity threshold as the denominator, and taking the ratio as the humidity accumulation amount at the outlet of the mixed cooling channel section.

[0050] According to the temperature performance value and the humidity accumulation 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 channel.

[0051] 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 inlet channel specifically includes: Based on the calculation formulas for the atomized water adjustment amount and the air intake adjustment amount of the air inlet channel, obtain the atomized water adjustment amount and the air intake adjustment amount of the air inlet channel. The calculation formulas for the atomized water adjustment amount and the air intake adjustment amount of the air inlet channel are: Among them, represents the air intake adjustment amount of the air inlet channel; represents the atomized water adjustment amount of the air inlet channel; represents the preset second feedback adjustment coefficient. In an embodiment of the present invention, Set to 0.05, The specific value of represents the cumulative humidity 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

[0052] Furthermore, the sum of the initial atomized water content and the atomized water adjustment amount of the air inlet channel can be used as the final atomized water content of the air inlet channel, and the sum of the initial air inlet volume and the air inlet adjustment amount of the air inlet channel can be used as the final air inlet volume of the air inlet channel, so as to realize the feedback adjustment of the initial atomized water content and the initial air inlet volume of the air inlet channel.

[0053] 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 channel can be specifically, for example: Wherein, represents the final atomized water content of the air inlet channel; represents the final air inlet volume of the air inlet channel; represents the initial atomized water content of the air inlet channel; represents the atomized water adjustment amount of the air inlet channel; represents the initial air inlet volume of the air inlet channel; represents the air inlet adjustment amount of the air inlet channel.

[0054] After determining the final atomized water content and the final air inlet volume of the air inlet channel, the initial cooling flue gas in the mixed cooling channel 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.

[0055] Preferably, in an embodiment of the present invention, the method for obtaining the final cooling flue gas specifically includes: 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 channel, so that the air intake of the cooling fan is the final air intake, and at the same time, the moisture content in the outside air in the air inlet channel is the final atomized water content. The moisture ejected from the nozzle is mixed with the outside air, and the initial cooled flue gas in the mixed cooling channel section is cooled by using the outside air containing moisture to obtain the final cooled flue gas.

[0056] Thus, the second cooling treatment of the flue gas is realized.

[0057] Step S4: Purify the final cooled flue gas.

[0058] After the above continuous two-stage cooling treatment of the high-temperature flue gas, the temperature of the high-temperature flue gas is reduced to a reasonable range. Then, the final cooled flue gas can be purified to improve the final purification effect.

[0059] Preferably, in an embodiment of the present invention, the method for purifying the final cooled flue gas specifically includes: First, dehydrate the final cooled flue gas to obtain the dehydrated final cooled flue gas. Then, pass the dehydrated final cooled flue gas through a dust collector, a desulfurization tower, and a denitrification reactor in sequence for purification treatment. After the flue gas after purification treatment meets the emission standards, it can be discharged into the atmosphere through a chimney.

[0060] 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 methods described in steps S1 to S4.

[0061] It should be noted that the above sequence of embodiments of the present invention is only for description and does not represent the advantages or 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.

[0062] Each embodiment in this specification is described in a progressive manner. The same or similar parts between each embodiment 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 comprises: Obtain the smoke temperature at the inlet and outlet of the independent cooling channel section at the current moment, as well as the smoke temperature and smoke humidity at the inlet and outlet of the mixed cooling channel section, and at the same time obtain the outside air temperature and air intake volume in the air intake channel interconnected with the mixed cooling channel section; According to the smoke temperature at the inlet and outlet of the independent cooling channel section, the water spraying amount of the independent cooling channel section is adjusted to obtain the real-time water spraying amount of the independent cooling channel section; based on the real-time water spraying amount, the smoke in the independent cooling channel section is cooled to obtain the initial cooled smoke; According to the flue gas temperature and flue gas humidity at the inlet of the mixed cooling channel section, and the outside air temperature and air intake in the air intake channel, the initial atomized water content and the initial air intake of the air intake channel are obtained; according to the flue gas temperature and flue gas humidity at the outlet of the mixed cooling channel section, the initial atomized water content and the initial air intake are adjusted to obtain the final atomized water content and the final air intake of the air intake channel; based on the final atomized water content and the final air intake, the initial cooling flue gas in the mixed cooling channel section is cooled to obtain the final cooling flue gas; The final cooled flue gas is purified.

2. A 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 channel section comprises: The flue gas temperature at the inlet of the independent cooling channel section is used as a numerator, the preset parameter is used as a denominator, and the ratio is used as the flue gas temperature ratio value at the inlet of the independent cooling channel section; the product value of the preset water spraying amount of the nozzle of the independent cooling channel section and the flue gas temperature ratio value at the inlet of the independent cooling channel section is used as the initial water spraying amount of the independent cooling channel section; The difference between the flue gas temperature at the outlet of the independent cooling channel section and the preset first high temperature threshold is used as the temperature deviation value at the outlet of the independent cooling channel section; the product value of the preset first feedback adjustment coefficient and the temperature deviation value is used as the water spray adjustment amount of the independent cooling channel section; The sum of the initial water spraying amount and the water spraying adjustment amount is used as the real-time water spraying amount of the independent cooling channel section.

3. A high-temperature flue gas purification method according to claim 1, characterized in that: The obtaining of the initial cooling flue gas comprises: The nozzles in the independent cooling channel section are used to spray water-cool the flue gas in the independent cooling channel 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 step of obtaining the initial atomized water content and the initial air intake volume of the air intake passage comprises: Inputting the flue gas temperature at the inlet of the mixed cooling channel section into an optimal atomization water content model, and outputting the optimal atomization water content of the mixed cooling channel section from the optimal atomization water content model; The sum of the air intake volume in the air intake channel and the air intake volume of the smoke in the pipeline is used as the comprehensive gas volume of the mixed cooling channel section; the product value of the optimal atomized water content and the comprehensive gas volume is used as the optimal moisture content of the mixed cooling channel section; The product of the intake volume of the smoke in the pipeline and the smoke humidity at the inlet of the mixed cooling channel section is used as the smoke moisture content at the inlet of the mixed cooling channel section; The difference between the optimum moisture content and the smoke moisture content is used as the numerator, the air volume in the air inlet channel is used as the denominator, and the ratio is used as the initial atomized water content of the air inlet channel; The initial air intake volume of the air intake channel is obtained according to the flue gas temperature at the inlet of the mixing cooling channel section, the outside air temperature in the air intake channel, the air intake volume of the flue gas in the pipeline, and the initial atomized water content of the mixing cooling channel section.

5. A high-temperature flue gas purification method according to claim 4, characterized in that: The obtaining of the initial air intake volume of the air intake channel comprises: Based on the calculation formula of the initial air intake volume of the air intake channel, the initial air intake volume of the air intake channel is obtained. The calculation formula of the initial air intake volume of the mixed cooling channel section is: in, Indicates the initial air volume of the air inlet channel; Indicates the amount of flue gas intake in the duct; Indicates the density of smoke in the duct; Indicates the specific heat capacity of the flue gas in the duct; Indicates the flue gas temperature at the inlet of the mixing cooling channel section; Indicates a preset second high temperature threshold; Indicates the density of the outside air in the air inlet channel; It represents the specific heat capacity of the outside air in the air inlet channel; Indicates the initial atomized water content in the air inlet channel; represents the specific heat capacity of water; Indicates the outside air temperature in the air inlet duct.

6. A high-temperature flue gas purification method according to claim 1, characterized in that: The method of obtaining the final atomized water content and the final air intake volume of the air intake passage comprises: The difference between the flue gas temperature at the outlet of the mixed cooling channel section and the preset second high temperature threshold is used as the numerator, the preset second high temperature threshold is used as the denominator, and the ratio is used as the temperature representation value of the outlet of the mixed cooling channel section; The difference between the smoke humidity at the outlet of the mixed cooling channel section and the preset humidity threshold is used as the numerator, the preset humidity threshold is used as the denominator, and the ratio is used as the humidity accumulation at the outlet of the mixed cooling channel section; According to the temperature performance value and the humidity accumulation at the outlet of the mixing cooling channel section, an atomized water adjustment amount and an air intake adjustment amount of the air intake channel are obtained; The sum of the initial atomized water content and the atomized water adjustment amount of the air inlet channel is used as the final atomized water content of the air inlet channel, and the sum of the initial air intake volume and the air intake adjustment amount of the air inlet channel is used as the final air intake volume of the air inlet channel.

7. A high-temperature flue gas purification method according to claim 6, characterized in that: The step of obtaining the atomized water adjustment amount and the air intake adjustment amount of the air intake passage comprises: Based on the calculation formula of the atomized water adjustment amount and the air intake adjustment amount of the air intake channel, the atomized water adjustment amount and the air intake adjustment amount of the air intake channel are obtained. The calculation formula of the atomized water adjustment amount and the air intake adjustment amount of the air intake channel is: in, Indicates the air intake adjustment amount of the air intake channel; Indicates the atomized water adjustment amount of the air inlet channel; Indicates a preset second feedback adjustment coefficient; Indicates the accumulated humidity at the outlet of the mixed cooling channel section; Indicates the temperature performance value of the outlet of the mixed cooling channel section; Indicates preset adjustment parameters; Represents the activation function.

8. A high-temperature flue gas purification method according to claim 1, characterized in that: The final cooling flue gas is obtained by: The operating power of the air cooler and the nozzle in the air inlet channel is adjusted so that the air inlet volume of the air cooler is the final air inlet volume, and the moisture content in the outside air in the air inlet channel is the final atomized water content, the moisture sprayed from the nozzle is mixed with the outside air, and the outside air containing moisture is used to cool the initial cooling flue gas in the mixed cooling channel section to obtain the final cooling flue gas.

9. A high-temperature flue gas purification method according to claim 1, characterized in that: The purification treatment of the final cooling flue gas comprises: The final cooling flue gas is dehydrated to obtain the dehydrated final cooling flue gas, and the dehydrated final cooling flue gas is sequentially introduced into a dust collector, a desulfurization tower and a denitrification reactor for purification.

10. 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, the steps of the method according to any one of claims 1 to 9 are implemented.

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