Desulfurization equipment for industrial waste gas in coking plant and desulfurization method thereof

Abstract

The invention relates to desulfurization equipment for industrial waste gas in a coking plant and a desulfurization method thereof, belonging to the technical field of preparation of desulfurization liquid in the coking plant. The desulfurization equipment recycles water vapor generated after heat exchange use in the coking plant, and meanwhile, the dual temperature control requirements during preparation of a desulfurization solution and desulfurization treatment of industrial waste gas in the coking plant are met. The desulfurization equipment comprises a dosing room, a desulfurization tower and an intelligent adjustment control system. The water vapor generated after heat exchange in the coking plant is recycled and used for preparing the desulfurization liquid at the proper temperature, then the desulfurization liquid is used for desulfurization treatment of the industrial waste gas, and the temperature of the desulfurization liquid is adjusted to the target temperature by controlling the mixing ratio of the normal-temperature water and the water vapor in the whole process, so that the energy consumption is reduced. According to the invention, the dual temperature control requirements during preparation of the desulfurization liquid and desulfurization treatment of the industrial waste gas in the coking plant can be met at the same time, and the problems that surplus steam and condensate water in the coking plant are difficult to recycle, and the temperature of the desulfurization liquid does not reach the standard and the desulfurization efficiency is low due to fluctuation of the environment temperature in the coking plant are solved.

Description

Technical Field

[0001] This invention relates to the field of desulfurization liquid preparation technology in coking plants, and particularly to a desulfurization device and method for industrial waste gas in coking plants. Background Technology

[0002] In the industrial production system of coking plants, steam is widely used as an important energy carrier in various processes. However, during steam use, a large amount of condensate generated after heat exchange is often directly discharged or left idle due to a lack of suitable recycling methods, resulting in serious waste of water resources and energy consumption. This also contradicts the current trend of green and circular industrial production.

[0003] On the other hand, desulfurization of industrial waste gas is also necessary, making the preparation of desulfurization liquid a crucial step in the coal gas purification process of coking plants. In this process, the solubility of soda ash, the core alkaline raw material, is significantly temperature-dependent, reaching its peak at 35.4℃. However, due to regional climate differences and diurnal temperature variations, it is difficult to maintain this temperature consistently during production, leading to fluctuations in soda ash dissolution efficiency and consequently, low water resource utilization. Furthermore, the activity of desulfurizing agents and catalysts is also temperature-sensitive, with the optimal activity temperature range concentrated between 30-45℃. If the temperature conditions are not met, their catalytic efficiency will be directly weakened, resulting in incomplete desulfurization reactions and ultimately low desulfurization efficiency, increasing the cost of subsequent coal gas purification and environmental governance pressures. Summary of the Invention

[0004] To address the challenges of recovering and utilizing surplus steam and condensate in coking plants, as well as the issues of substandard desulfurization liquid temperature and low desulfurization efficiency due to ambient temperature fluctuations within coking plants, this invention discloses a desulfurization device and method for industrial waste gas in coking plants.

[0005] The first aspect of this invention provides a desulfurization device for industrial waste gas in a coking plant. This device recovers and utilizes water vapor generated after heat exchange within the coking plant, simultaneously meeting the dual temperature requirements during desulfurization liquid preparation and industrial waste gas desulfurization treatment. The desulfurization device includes: a dosing room containing several sets of dissolving tanks, each set including a first dissolving tank for preparing an alkaline solution and a second dissolving tank for preparing a desulfurization liquid using the alkaline solution; a desulfurization tower that uses the desulfurization liquid to treat the industrial waste gas; a cooling tower that uses ambient temperature water to react with water vapor to form cooling water, which is then transported to the first dissolving tank; and an intelligent adjustment and control system that regulates the temperature of the desulfurization liquid to the target temperature by controlling the mixing ratio of ambient temperature water and water vapor.

[0006] As a further improvement to the above scheme, the intelligent regulation and control system includes a controller, control valve one, control valve two, and a temperature sensor; the temperature sensor detects the actual temperature of the desulfurization liquid, and the controller controls the opening degree of control valve one and control valve two according to the actual temperature and target temperature of the desulfurization liquid, so as to control the input amount of water vapor and room temperature water in the cooling tower respectively.

[0007] Furthermore, when the actual temperature is ≤-10℃ and the target temperature of the desulfurization liquid is 43℃, the opening degree of control valve one is 80% and the opening degree of control valve two is 20%; when the actual temperature is -10~-5℃ and the target temperature of the desulfurization liquid is 42℃, the opening degree of control valve one is 70% and the opening degree of control valve two is 30%; when the actual temperature is -5~5℃ and the target temperature of the desulfurization liquid is 41℃, the opening degree of control valve one is 65% and the opening degree of control valve two is 35%; when the actual temperature is 5~15℃ and the target temperature of the desulfurization liquid is 40℃, the opening degree of control valve one is 50% and the opening degree of control valve two is 50%; when the actual temperature is 15~25℃ and the target temperature of the desulfurization liquid is 39℃, the opening degree of control valve one is 45% and the opening degree of control valve two is 55%; when the actual temperature is ≥25℃ and the target temperature of the desulfurization liquid is 38℃, the opening degree of control valve one is 40% and the opening degree of control valve two is 60%.

[0008] Furthermore, when the deviation between the actual temperature and the target temperature is within the preset range, the current opening degree of control valve one and control valve two is readjusted according to the predetermined value.

[0009] Preferably, when the deviation between the actual temperature and the target temperature is ≤-1℃, the current opening of control valve one increases by 10%, and the current opening of control valve two decreases by 5%; when the deviation between the actual temperature and the target temperature is ≤-0.5℃, the current opening of control valve one increases by 5%, and the current opening of control valve two decreases by 3%; when the deviation between the actual temperature and the target temperature is ≤-0.2℃, the current opening of control valve one increases by 2%, and the current opening of control valve two decreases by 1%; when the deviation between the actual temperature and the target temperature is ≤+0.2℃, the current opening of control valve one decreases by 2%, and the current opening of control valve two increases by 1%; when the deviation between the actual temperature and the target temperature is ≤+0.5℃, the current opening of control valve one decreases by 5%, and the current opening of control valve two increases by 3%; when the deviation between the actual temperature and the target temperature is ≤+1℃, the current opening of control valve one decreases by 10%, and the current opening of control valve two increases by 5%.

[0010] Furthermore, the intelligent regulation and control system also includes a level gauge for detecting the condensate level in the cooling tower. The controller also determines whether the condensate level in the cooling tower is within a preset level range: if the condensate level is below the minimum limit of the level range, the system continues to monitor the condensate level; if the condensate level is above the maximum limit of the level range, control valve one and control valve two are closed.

[0011] Preferably, the intelligent adjustment and control system further includes: a control valve three for controlling the amount of condensate delivered to dissolving tank one; a feeder for controlling the amount of soda ash delivered to dissolving tank one; a feeder for controlling the amount of desulfurizing agent and desulfurization catalyst added to dissolving tank two; and a pump for controlling the amount of alkaline solution delivered from dissolving tank one to dissolving tank two. The controller is also used to maintain a preset matching ratio between the amount of condensate delivered and the amount of soda ash delivered to dissolving tank one within a unit time by controlling control valve three and the feeder; and to maintain a preset matching ratio between the amount of alkaline solution delivered and the amount of desulfurizing agent and desulfurization catalyst added to dissolving tank two within a unit time by controlling the pump and the feeder.

[0012] Preferably, the intelligent adjustment and control system further includes a booster pump for transporting the desulfurization liquid in the dissolving tank to the desulfurization tower for desulfurization treatment. The controller is also used to control the amount of desulfurization liquid transported to the desulfurization tower by controlling the booster pump.

[0013] As a further improvement to the above scheme, the cooling tower is equipped with a spray pipe network, baffles, and steam pipe network from top to bottom. The spray pipe network sprays water mist into the cooling tower, and the steam pipe network introduces water vapor into the cooling tower. Under the guiding effect of the baffles, the condensation of water vapor by the water mist is accelerated.

[0014] The second aspect of the present invention also provides a desulfurization treatment method for industrial waste gas in a coking plant, which adopts any of the above-mentioned desulfurization equipment for industrial waste gas in a coking plant, and utilizes the water vapor generated after heat exchange in the coking plant to simultaneously meet the dual temperature requirements during the preparation of desulfurization liquid and the desulfurization treatment of industrial waste gas.

[0015] The advantages of this invention are: 1. This invention recycles and utilizes water vapor generated after heat exchange in a coking plant. The water vapor is cooled by the reaction of ambient temperature water with the cooling water, which is then used to prepare a desulfurization solution at a suitable temperature. This solution is then used for the desulfurization treatment of industrial waste gas within the coking plant. The entire process involves controlling the mixing ratio of ambient temperature water and water vapor to adjust the temperature of the desulfurization solution to the target temperature. Therefore, this invention can simultaneously meet the dual temperature control requirements during both the preparation of the desulfurization solution and the desulfurization treatment of industrial waste gas within the coking plant. It solves the problems of difficulty in recycling excess steam and condensate in coking plants, as well as the issues of substandard desulfurization solution temperature and low desulfurization efficiency caused by fluctuations in the ambient temperature within the coking plant.

[0016] 2. Efficient recovery of steam and condensate to improve resource utilization: Innovatively utilizes excess steam and condensate generated during the factory production process as a source of water for desulfurization liquid preparation, avoiding the waste of water resources and heat energy caused by direct discharge of condensate, realizing industrial water recycling, reducing water costs and energy consumption in coking plants, and conforming to the concept of green production.

[0017] 3. Precise temperature control optimizes desulfurization solution preparation, improving dissolution and desulfurization efficiency: The system determines the opening degree of control valve one and control valve two, as well as the target temperature of the desulfurization solution, based on the ambient temperature of the system. Then, by detecting the temperature of the generated desulfurization solution, the opening degree of control valve one and control valve two is finely adjusted according to the feedback, so that the generated desulfurization solution is always within a suitable temperature range, ensuring that soda ash dissolves quickly and fully. Compared with the fluctuating conditions caused by temperature differences in conventional water sources, the dissolution efficiency is significantly improved, reducing soda ash waste and water consumption. At the same time, the temperature carried by the prepared desulfurization solution can also avoid the decline in catalytic efficiency caused by temperature fluctuations.

[0018] 4. The controller sets the target temperature based on the external ambient temperature and fine-tunes the opening of control valve one and control valve two according to the temperature deviation to ensure that the condensate is always kept within the range of 38-43℃ under different seasons and ambient temperatures (such as around 38℃). As a result, the temperature when preparing desulfurization water is always kept at around 35.4℃, and the temperature of desulfurization treatment is always kept within the optimal activity range of 30-45℃. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a desulfurization device for industrial waste gas in a coking plant, provided in an embodiment of the present invention.

[0020] Figure 2 yes Figure 1 A schematic diagram of the control architecture of the intelligent adjustment and control system for desulfurization equipment. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] It should be noted that when a component is said to be "installed on" another component, it can be directly on the other component or it may be in a component that is centered on it. When a component is said to be "set on" another component, it can be directly set on the other component or it may also be in a component that is centered on it. When a component is said to be "fixed to" another component, it can be directly fixed to the other component or it may also be in a component that is centered on it.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0024] Please refer to Figure 1 , Figure 1 This is a schematic diagram of a desulfurization device for industrial waste gas in a coking plant, provided by an embodiment of the present invention. The desulfurization device mainly includes a desulfurization liquid preparation system, a desulfurization tower 23, and an intelligent regulation and control system. The desulfurization liquid preparation system includes a cooling tower 1 and a dosing room 15. The dosing room 15 is equipped with several sets of dissolving tanks, each set including a dissolving tank 14 for preparing an alkaline solution and a dissolving tank 20 for preparing desulfurization liquid using the alkaline solution. The desulfurization tower 23 uses the desulfurization liquid to desulfurize the industrial waste gas. The cooling tower 1 recovers and utilizes the water vapor generated after heat exchange within the coking plant, simultaneously meeting the dual temperature requirements during desulfurization liquid preparation and industrial waste gas desulfurization treatment. The intelligent regulation and control system adjusts the desulfurization liquid temperature to the target temperature by controlling the mixing ratio of room temperature water and water vapor.

[0025] Cooling tower 1 is used to recover the large amount of water vapor generated in the coking plant after heat exchange. It utilizes ambient temperature water to react with the water vapor to form cooling water, which is then transported to dissolving tank 14. Cooling tower 1 receives water vapor through pipe 8 and ambient temperature water through pipe 4. To control the input of water vapor and the delivery time, control valve 7 can be installed in pipe 8, and to control the input of ambient temperature water and the delivery time, control valve 3 can be installed in pipe 4. The control system rationally configures the mixing ratio of ambient temperature water and water vapor in cooling tower 1 to form temperature-controlled water that maintains the water temperature at the target temperature. The target temperature is lower than the temperature of the water vapor. The ambient temperature water temperature refers to the natural temperature, such as the temperature of tap water (the temperature under natural conditions without heating or cooling). The chemical dosing room 15 uses the temperature-controlled water to prepare desulfurization liquid according to the desulfurization liquid preparation process requirements. The prepared desulfurization liquid can be transported to desulfurization tower 23 for use via a transmission system.

[0026] The cooling tower 1 is equipped with a spray pipe network 2, baffles 5, and steam pipe network 6 arranged sequentially from top to bottom. The steam pipe network 6 is connected to pipe 8 and receives water vapor from pipe 8, which is then introduced into the cooling tower 1. The spray pipe network 2 is connected to pipe 4 and receives ambient temperature water from pipe 4, which is used to spray water mist into the cooling tower 1 to contact the water vapor and condense it into condensate. The condensate flows to the bottom of the cooling tower 1, where a drain outlet is provided. To facilitate condensate drainage, the bottom of the cooling tower 1 can be funnel-shaped, with the drain outlet located at the bottom of the funnel. A level gauge 24 can be installed inside the cooling tower 1 to detect the water level after condensate accumulation.

[0027] To improve the efficiency of condensate formation, several baffles 5 can be installed. Their function is to ensure that the water mist sprayed from the spray network 2 and the steam sprayed from the steam network 6 are evenly distributed and to prolong the contact time between them. The installation direction of the baffles 5 within the cooling tower 1 is as parallel as possible to the rising direction of the steam to accelerate condensation. All baffles 5 are generally parallel to each other. There are many types of baffles 5: single-arch baffles, double-arch baffles, arched sections without pipes, perforated baffles, baffle rods, annular baffles, rectangular baffles, etc. In this embodiment, a single-arch baffle is used, and the baffle path extends from the side facing the spray network 2 to the side facing the steam network 6. The rising steam sprayed from the steam network 6 contacts the water mist sprayed from the spray network 2, and with the aid of the baffles 5, condensate quickly forms on the baffles 5, falling in large droplets. Therefore, the water mist output from the spray pipe network 2 diffuses downward under the action of gravity, while the water vapor output from the steam pipe network 6 rises upward under the action of rising. Under the guiding action of the baffle plate 5, the water mist and water vapor can be fully mixed and condensed.

[0028] The chemical dosing room 15 may be equipped with several sets of dissolving tanks, each set including dissolving tank 14 and dissolving tank 20. Cooling tower 1, dissolving tank 14, and dissolving tank 20 are connected sequentially. The connection between cooling tower 1 and dissolving tank 14 can be via pipe 3 25. To better control the condensate delivery volume and delivery time, a control valve 3 9 can be installed on pipe 3 25. The connection between dissolving tank 14 and dissolving tank 20 can be via pipe 4 26. To better control the delivery volume and delivery time, a pump 17 can be installed on pipe 4 26.

[0029] In the preparation process of the desulfurization liquid, soda ash is first added to dissolving tank 14. Then, the soda ash is fully dissolved using the condensate flowing from cooling tower 1 (at the target temperature). After thorough mixing by mixer 12, an alkaline solution is formed. This alkaline solution is then transported to dissolving tank 20, where desulfurizing agent and desulfurization catalyst are added according to a preset ratio. After thorough mixing by mixer 19, the desulfurization liquid is formed and can be output through pipeline 27. During use, a booster pump 22 can be installed on pipeline 27 to transport the desulfurization liquid to desulfurization tower 23. A temperature sensor 21 can also be installed on pipeline 27 to detect the temperature of the desulfurization liquid. Alternatively, the temperature sensor 21 can be installed at the desulfurization liquid outlet of dissolving tank 20 to detect the temperature of the desulfurization liquid.

[0030] The addition of soda ash can be achieved by installing a discharge mechanism 1 at the top of the dosing room 15. Of course, as long as it does not affect the addition of soda ash to the dissolving tank 14 or the performance of the soda ash, the discharge mechanism 1 can be installed in any location. The discharge mechanism 1 may include a discharge trough 10, a discharge pipe 13, and a feeder 11. The discharge trough 10 is used to hold soda ash and is connected to the dissolving tank 14 through the discharge pipe 13, which discharges the soda ash into the dissolving tank 14. The feeder 11, installed in the discharge pipe 13, can be used to control whether soda ash needs to be discharged into the dissolving tank 14, and the specific amount to be discharged. To facilitate the full dissolution of soda ash in the condensate, a stirrer 12 can be added to the dissolving tank 14. The motor of the stirrer 12 can be located on the top of the outer wall of the dissolving tank 14. One end of the drive shaft of the stirrer 12 is driven to rotate by the motor, and the other end extends into the dissolving tank 14 and is equipped with several blades. The motor drives the blades to rotate in the condensate, accelerating the dissolution of soda ash in the condensate.

[0031] The addition of desulfurizing agent and desulfurization catalyst can also be achieved by installing a discharge mechanism 2 on the top of the dosing room 15. The discharge mechanism 2 can be set up with reference to the discharge mechanism 1. A feeder 18 can be installed on the top of the dissolving tank 20 to control the amount of desulfurizing agent and desulfurization catalyst added to the dissolving tank 20. Alternatively, a mixer 2 19 can be installed to stir the liquid in the dissolving tank 20.

[0032] The intelligent regulation and control system may include a controller 16, control valve 7, control valve 3, control valve 9, feeder 11, feeder 18, temperature sensor 21, and level gauge 24. All three control valves can be solenoid valves. The control method of the intelligent regulation and control system is as follows: Figure 2As shown, controller 16 controls the feeding frequency of soda ash through the feeding valve 11 according to the set soda ash feeding amount; it can also control the feeding frequency of desulfurizing agent and desulfurization catalyst through the feeder 18 according to the set desulfurizing agent and desulfurization catalyst; it can also control the opening ratio of control valve 7 and control valve 3 according to the set target temperature (i.e., temperature index) detected by temperature sensor 21; and it can control the opening degree of control valve 9 according to the liquid level detected by level gauge 24 and the liquid level index of cooling tower. Therefore, controller 16 can control the water temperature of condensate through control valve 7 and control valve 3, maintaining the water temperature above the target temperature, such as 40°C.

[0033] In this embodiment, the controller 16 controls the opening of control valve 7 and control valve 3 according to the actual temperature and target temperature of the desulfurization liquid, so as to control the input of water vapor and room temperature water in the cooling tower 1 respectively. When the deviation between the actual temperature and the target temperature is within a preset range, the controller 16 can also readjust the current opening of control valve 7 and control valve 3 according to a predetermined value. The controller 16 is also used to determine whether the condensate level in the cooling tower 1 is within a preset level range: if the condensate level is lower than the minimum limit of the level range, the condensate level is further determined; if the condensate level is higher than the maximum limit of the level range, control valve 7 and control valve 3 are closed. The controller 16 is also used to control the condensate delivery rate and soda ash delivery rate in the dissolving tank 14 to maintain a preset matching ratio within a unit time by controlling control valve 9 and feeder 11; and to control the alkaline solution delivery rate and the input amount of desulfurizing agent and desulfurization catalyst in the dissolving tank 20 to maintain a preset matching ratio within a unit time by controlling pump 17 and feeder 18. The controller 16 is also used to control the amount of desulfurization liquid delivered to the desulfurization tower 23 by controlling the booster pump 22.

[0034] This invention relates to a desulfurization liquid preparation system for coking plants, belonging to the field of desulfurization liquid preparation technology. Its aim is to achieve efficient recycling of the large amount of water vapor generated after heat exchange within the coking plant and to improve the quality of the desulfurization liquid in the preparation process. In the desulfurization liquid preparation process, soda ash, as a key alkaline component, reaches its maximum solubility at 35.4℃, facilitating rapid dissolution to form an alkaline solution. Simultaneously, the optimal temperature range for the activity of the desulfurizing agent and desulfurization catalyst is 30-45℃. However, due to seasonal changes and diurnal temperature variations, the temperature of conventional water sources fluctuates significantly, making it difficult to meet the temperature control requirements for desulfurization liquid preparation. Therefore, this invention introduces the large amount of water vapor generated after heat exchange within the coking plant as a temperature control medium, ensuring a stable reaction environment through precise temperature regulation.

[0035] In actual operation, the intelligent adjustment and control system can set the target temperature to 40℃. Temperature sensor 21 monitors the temperature of the desulfurization liquid in real time and dynamically adjusts the opening of control valve 7 and control valve 3 to control the temperature of the condensate. In the preparation process, soda ash is first added to dissolving tank 14, where it is fully dissolved using temperature-controlled condensate to form an alkaline solution, which is then transferred to dissolving tank 20. In dissolving tank 20, desulfurizing agent and desulfurization catalyst are precisely added according to a preset ratio. After thorough mixing, the desulfurization liquid is transported to the desulfurization tower 23 by booster pump 22.

[0036] This technical solution not only effectively solves the problem of recovering a large amount of water vapor generated after heat exchange in coking plants, but also improves the quality of desulfurization liquid through systematic temperature control, significantly enhancing desulfurization efficiency. It has both environmental benefits and economic value, providing an innovative path for energy-saving optimization of desulfurization processes in coking plants.

[0037] The desulfurization liquid preparation method of the desulfurization liquid preparation system in the coking plant of the present invention includes the following steps.

[0038] S1 controls the opening of control valve 7 and control valve 3 according to the actual temperature and target temperature of the desulfurization liquid, so as to control the input of water vapor and room temperature water in cooling tower 1 respectively.

[0039] The system determines the temperature range of the desulfurization liquid and controls the opening of control valve 7 and control valve 3 accordingly. When the desulfurization liquid preparation system starts up, if there is no desulfurization liquid in dissolving tank 20, temperature sensor 21 detects the ambient temperature; if there is desulfurization liquid, temperature sensor 21 detects the temperature of the desulfurization liquid. Neither the ambient temperature nor the temperature of the desulfurization liquid affects the control of control valve 7 and control valve 3.

[0040] When control valve 1 (7) and control valve 2 (3) are opened, room temperature water (approximately 20℃-25℃) is transported to spray network 2 through pipe 2 (4), and water mist is sprayed downwards from spray network 2. At the same time, water vapor (high temperature, generally ≥80℃) is transported to steam network 6 through pipe 1 (8). The room temperature water and water vapor meet and form condensate, which flows into the bottom of cooling tower 1.

[0041] The relationship between the temperature of the desulfurization liquid and the opening degree of control valve 7 and control valve 3 is shown in Table 1.

[0042] Table 1 Temperature and Opening Control Table for Control Valve 7 and Control Valve 3 As shown in Table 1, the control method of controller 16 is as follows: When the actual temperature is ≤-10℃ and the target temperature of the desulfurization liquid is 43℃, control valve 7 is opened at 80% and control valve 3 is opened at 20%. When the actual temperature is -10 to -5℃ and the target temperature of the desulfurization liquid is 42℃, control valve 17 is opened at 70% and control valve 23 is opened at 30%. When the actual temperature is -5 to 5℃ and the target temperature of the desulfurization liquid is 41℃, the opening degree of control valve 17 is 65% and the opening degree of control valve 23 is 35%. When the actual temperature is 5-15℃ and the target temperature of the desulfurization liquid is 40℃, control valve 1-7 is opened at 50% and control valve 2-3 is opened at 50%. When the actual temperature is 15-25℃ and the target temperature of the desulfurization liquid is 39℃, the opening degree of control valve 17 is 45% and the opening degree of control valve 23 is 55%. When the actual temperature is ≥25℃ and the target temperature of the desulfurization liquid is 38℃, the opening degree of control valve 17 is 40% and the opening degree of control valve 23 is 60%.

[0043] The controller 16 compares the detected desulfurization liquid temperature with a dynamically set "suitable temperature range" based on the ambient temperature. This "suitable temperature range" is not a fixed value; due to the large temperature difference between summer and winter, and the temperature drop of the desulfurization liquid during transport to the desulfurization tower (especially significant in winter), it needs to be dynamically adjusted: the target temperature is ≤43℃ in winter and ≥38℃ in summer. The controller 16 determines the current target control temperature and the corresponding initial solenoid valve opening based on the real-time detected ambient temperature (which can be set via an additional atmospheric temperature sensor or manual input).

[0044] If temperature sensor 21 detects that the desulfurization liquid temperature deviates from the current target control temperature, controller 16 calculates the temperature deviation (detected temperature - target control temperature) and fine-tunes the opening of control valve 7 and control valve 3 according to the magnitude of the deviation. By changing the ratio of hot and cold fluids, the temperature of the mixed solution is precisely controlled, thereby regulating the final temperature of the desulfurization liquid. The fine-tuning strategy is shown in Table 2, the solenoid valve opening fine-tuning table: Table 2. Fine-tuning table for the opening of control valve 1 (7) and control valve 2 (3) As shown in Table 2, the control method of controller 16 may also include: When the deviation between the actual temperature and the target temperature is ≤-1℃, the current opening degree of control valve 7 increases by 10%, and the current opening degree of control valve 3 decreases by 5%. When the deviation between the actual temperature and the target temperature is ≤-0.5℃, the current opening degree of control valve 7 increases by 5%, and the current opening degree of control valve 3 decreases by 3%. When the deviation between the actual temperature and the target temperature is ≤ -0.2℃, the current opening degree of control valve 7 increases by 2%, and the current opening degree of control valve 3 decreases by 1%. When the deviation between the actual temperature and the target temperature is ≤ +0.2℃, the current opening degree of control valve 7 decreases by 2%, and the current opening degree of control valve 3 increases by 1%. When the deviation between the actual temperature and the target temperature is ≤ +0.5℃, the current opening degree of control valve 7 decreases by 5%, and the current opening degree of control valve 3 increases by 3%. When the deviation between the actual temperature and the target temperature is ≤ +1℃, the current opening of control valve 7 decreases by 10%, and the current opening of control valve 3 increases by 5%.

[0045] For example, if the current target control temperature is 43℃, but the detected desulfurization liquid temperature is 45℃, then the temperature deviation is +2℃ (≥+1℃). In this case, controller 16 will increase the opening of control valve 2 (3) by 5% and decrease the opening of control valve 1 (7) by 10% based on the current initial opening. That is, the opening of control valve 2 (3) is now 25%, and the opening of control valve 1 (7) is 70%.

[0046] During the opening of control valves 2 (3) and 1 (7) for temperature regulation, the liquid level in cooling tower 1 will rise. If the liquid level rises to the set high level, controller 16 will close control valves 2 (3) and 1 (7) to stop feeding and prevent overflow. Subsequently, the system will repeat the complete process of preparing desulfurization liquid (feeding, stirring, transfer, chemical addition, and re-stirring) and check the temperature of the newly prepared desulfurization liquid again until its temperature stabilizes within the target range.

[0047] S2, determine whether the condensate level in cooling tower 1 is within the preset level range. If the condensate level is lower than the minimum limit of the level range, return to step S2. If the condensate level is higher than the maximum limit of the level range, proceed to step S3. If the condensate level is within the level range, proceed to step S4.

[0048] The logic of controller 16 controlling control valve 23 and control valve 17 is as follows: when the liquid level in the cooling tower is lower than the low liquid level, control valve 23 and control valve 17 are opened to ensure that the liquid level in the cooling tower is always greater than or equal to the low liquid level. When the liquid level rises to the high liquid level due to the opening of control valve 23 and control valve 17 caused by temperature regulation, control valve 23 and control valve 17 are closed to prevent overflow.

[0049] S3, close control valve 1 (7) and control valve 2 (3).

[0050] S4, open control valve 39, feeder 11 and mixer 12, the flow rate of condensate delivered by control valve 39 and the amount of soda ash fed by feeder 11 maintain a preset matching ratio within a unit time.

[0051] When the feeder 11 on the feed pipe 13 is opened, the soda ash in the feed trough 10 can fall into the dissolving tank 14 by gravity through the feed pipe 13. When the control valve 9 on the pipe 25 is opened, the condensate from the cooling tower 1 can flow into the dissolving tank 14 by gravity through the pipe 25, and then the condensate and soda ash are stirred by the agitator 12. The density of the alkaline solution in the dissolving tank 14 can be monitored by a density detector.

[0052] S5, start pump 17, feeder 18 and mixer 12, the amount of desulfurizing agent and desulfurizing catalyst added by feeder 18 and the amount of alkaline solution delivered by pump 17 maintain a preset matching ratio within a unit time.

[0053] When pump 17 on pipeline 426 is turned on, the alkaline solution in dissolving tank 14 can be transported to dissolving tank 20. When feeder 18 is turned on, desulfurizing agent and desulfurization catalyst are added to dissolving tank 20. Then, the alkaline solution, desulfurizing agent and desulfurization catalyst are stirred by mixer 219.

[0054] S6, turn on the booster pump 22 to transport the desulfurization liquid in the dissolving tank 20 to the desulfurization tower 23 for desulfurization reaction.

[0055] Through continuous monitoring and feedback fine-tuning of the above control system, the temperature of the final output desulfurization liquid can be precisely controlled, effectively avoiding the decline in the efficiency of the desulfurization catalyst due to temperature fluctuations, and ensuring the stable and efficient operation of the desulfurization process.

[0056] Of course, the entire process can also be carried out in real time. For example, the temperature of the desulfurization liquid in the dissolution tank 20 needs to be monitored in real time, that is, the temperature detected by the temperature sensor 21 is acquired in real time for temperature determination. The condensate level in the cooling tower 1 also needs to be monitored in real time, that is, the level detected by the level gauge 24 is acquired in real time for level determination. Therefore, temperature determination and level determination can also be carried out in real time.

[0057] In summary, the desulfurization liquid preparation system for coking plants of the present invention has the following beneficial effects.

[0058] 1. Highly efficient water vapor recovery, improving resource utilization. The condensate formed by the large amount of water vapor (steam network 6) generated after heat exchange in the coking plant and mixed with water mist (room temperature water sprayed out through spray network 2) is used as the water source for desulfurization liquid preparation. This avoids the waste of water resources and heat energy caused by direct discharge of water vapor, realizes industrial water recycling, reduces water cost and energy consumption in the coking plant, and is in line with the concept of green production.

[0059] 2. Precise temperature control optimizes desulfurization solution preparation and improves dissolution efficiency. By dynamically adjusting the temperature of steam and room temperature water to above 40°C through the control system, soda ash is ensured to dissolve quickly and fully. Compared with the fluctuating operating conditions caused by temperature differences in conventional water sources, the dissolution efficiency is significantly improved, reducing soda ash waste and water consumption.

[0060] 3. Stabilizes catalyst activity and significantly improves desulfurization efficiency. The control system precisely maintains the reaction temperature at the optimal activity level of the desulfurizing agent and catalyst, avoiding a decrease in catalytic efficiency due to temperature fluctuations, thus making the desulfurization reaction more complete, improving desulfurization efficiency, and reducing subsequent coal gas purification costs and environmental governance pressure.

[0061] 4. Systematic integrated design enables intelligent and precise control. The control system, through linkage with temperature sensors and solenoid valves, monitors and dynamically adjusts the water temperature in real time. It can adapt to day-night temperature differences and seasonal changes without manual intervention, solving the problem of unstable temperature control in traditional processes and improving the automation and reliability of desulfurization liquid preparation.

[0062] 5. It possesses both environmental and economic value, driving technological upgrades. This technology not only fills the gap in the industry regarding the recovery of large amounts of water vapor generated after heat exchange in coking plants, but also improves the efficiency of desulfurization processes through temperature control optimization, reducing wastewater discharge and energy consumption, bringing direct economic benefits to coking plants, and providing an innovative demonstration for the energy-saving and intelligent upgrading of desulfurization processes.

[0063] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0064] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A desulfurization device for industrial waste gas in a coking plant, comprising: a dosing chamber (15) in which a plurality of groups of dissolving tanks are arranged, each group of dissolving tanks including a dissolving tank one (14) for preparing an alkaline solution and a dissolving tank two (20) for preparing a desulfurization solution by using the alkaline solution; a desulfurization tower (23) for desulfurization treatment of the industrial waste gas in the coking plant by using the desulfurization solution; characterized in that the desulfurization device recycles water vapor generated after heat exchange in the coking plant, while meeting the dual temperature requirements of desulfurization solution preparation and industrial waste gas desulfurization treatment, and further comprising: a cooling tower (1) for forming cooling water by meeting water vapor with normal temperature water and delivering the cooling water into the dissolving tank one (14); an intelligent adjustment control system for adjusting the temperature of the desulfurization solution to a target temperature by controlling the mixing ratio of the normal temperature water and the water vapor.

2. The apparatus for desulfurization of industrial waste gas in a coking plant according to claim 1, characterized by, The intelligent adjustment control system includes a controller (16), a control valve one (7), a control valve two (3), and a temperature sensor (21); the temperature sensor (21) detects the actual temperature of the desulfurization solution, and the controller (16) controls the opening degrees of the control valve one (7) and the control valve two (3) according to the actual temperature and the target temperature of the desulfurization solution to control the input amounts of the water vapor and the normal temperature water in the cooling tower (1) respectively.

3. The apparatus for desulfurization of industrial waste gas in a coking plant according to claim 2, characterized by, The control method of the controller (16) includes: when the actual temperature is ≤-10℃ and the target temperature of the desulfurization solution is 43℃, the opening degree of the control valve one (7) is 80% and the opening degree of the control valve two (3) is 20%; when the actual temperature is -10~-5℃ and the target temperature of the desulfurization solution is 42℃, the opening degree of the control valve one (7) is 70% and the opening degree of the control valve two (3) is 30%; when the actual temperature is -5~5℃ and the target temperature of the desulfurization solution is 41℃, the opening degree of the control valve one (7) is 65% and the opening degree of the control valve two (3) is 35%; when the actual temperature is 5~15℃ and the target temperature of the desulfurization solution is 40℃, the opening degree of the control valve one (7) is 50% and the opening degree of the control valve two (3) is 50%; when the actual temperature is 15~25℃ and the target temperature of the desulfurization solution is 39℃, the opening degree of the control valve one (7) is 45% and the opening degree of the control valve two (3) is 55%; when the actual temperature is ≥25℃ and the target temperature of the desulfurization solution is 38℃, the opening degree of the control valve one (7) is 40% and the opening degree of the control valve two (3) is 60%.

4. The apparatus for desulfurization of industrial waste gas in a coking plant according to claim 3, characterized by, When the deviation between the actual temperature and the target temperature is within a preset range, the controller (16) adjusts the current opening degrees of the control valve one (7) and the control valve two (3) again according to the predetermined values.

5. The apparatus for desulfurization of industrial off-gas in a coking plant according to claim 4, characterized in that, The control method of the controller (16) further includes: when the deviation between the actual temperature and the target temperature is ≤-1℃, the current opening degree of the control valve one (7) is increased by 10% and the current opening degree of the control valve two (3) is reduced by 5%; when the deviation between the actual temperature and the target temperature is ≤-0.5℃, the current opening degree of the control valve one (7) is increased by 5% and the current opening degree of the control valve two (3) is reduced by 3%; when the deviation between the actual temperature and the target temperature is ≤-0.2℃, the current opening degree of the control valve one (7) is increased by 2% and the current opening degree of the control valve two (3) is reduced by 1%. When the deviation between the actual temperature and the target temperature is ≤+0.2℃, the current opening of the control valve one (7) is reduced by 2%, and the current opening of the control valve two (3) is increased by 1%; When the deviation between the actual temperature and the target temperature is ≤+0.5℃, the current opening of the control valve one (7) is reduced by 5%, and the current opening of the control valve two (3) is increased by 3%; When the deviation between the actual temperature and the target temperature is ≤+1℃, the current opening of the control valve one (7) is reduced by 10%, and the current opening of the control valve two (3) is increased by 5%.

6. The apparatus for desulfurization of industrial waste gas in a coking plant according to claim 2, characterized by, The intelligent adjustment control system further comprises: a liquid level meter (24) for detecting the condensate water level in the cooling tower (1); The controller (16) is further configured to determine whether the condensate water level in the cooling tower (1) is within a preset liquid level range: if the condensate water level is below the lower limit of the liquid level range, the determination of the condensate water level continues; if the condensate water level is above the upper limit of the liquid level range, the control valve one (7) and the control valve two (3) are closed.

7. The apparatus for desulfurization of industrial off-gas within a coking plant according to claim 6, characterized in that, The intelligent adjustment control system further comprises: a control valve three (9) for controlling the delivery amount of the condensate water into the dissolving tank one (14); a feeder (11) for controlling the discharge amount of the soda ash into the dissolving tank one (14); a feeder (18) for controlling the input amount of the desulfurizing agent and the desulfurizing catalyst into the dissolving tank two (20); a pump (17) for controlling the delivery amount of the alkaline solution in the dissolving tank one (14) into the dissolving tank two (20); The controller (16) is further configured to control the delivery amount of the condensate water and the discharge amount of the soda ash in the dissolving tank one (14) to maintain a preset matching ratio within a unit time by controlling the control valve three (9) and the feeder (11), and to control the delivery amount of the alkaline solution in the dissolving tank two (20) and the input amount of the desulfurizing agent and the desulfurizing catalyst to maintain a preset matching ratio within a unit time by controlling the pump (17) and the feeder (18).

8. The apparatus for desulfurization of industrial off-gas within a coking plant according to claim 7, characterized in that, The intelligent adjustment control system further comprises: a booster pump (22) for delivering the desulfurizing solution in the dissolving tank two (20) to the desulfurizing tower (23) for desulfurization treatment; The controller (16) is further configured to control the delivery amount of the desulfurizing solution into the desulfurizing tower (23) by controlling the booster pump (22).

9. The apparatus for desulfurization of industrial off-gas in a coking plant according to claim 1, characterized in that, The cooling tower (1) is sequentially provided from top to bottom with a spray pipe network (2), a baffle (5), and a steam pipe network (6); the spray pipe network (2) sprays water mist in the cooling tower (1), and the steam pipe network (6) introduces water vapor into the cooling tower (1), which, under the guiding action of the baffle (5), accelerates the condensation of the water mist on the water vapor.

10. A method for desulfurization treatment of industrial waste gas in a coking plant, characterized by, The desulfurization device for industrial waste gas in a coking plant adopts the desulfurization device for industrial waste gas in a coking plant according to any one of claims 1 to 9, uses the water vapor generated after heat exchange in the coking plant, and simultaneously meets the double temperature requirements of desulfurizing solution preparation and industrial waste gas desulfurization treatment.

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