Repeated adsorption treatment system for SRG flue gas in sintering flue gas desulfurization and denitrification process

Abstract

The utility model belongs to the technical field of industrial waste gas treatment, and discloses a repeated adsorption treatment system for SRG flue gas in a sintering flue gas desulfurization and denitrification process. According to the repeated adsorption treatment system, a re-adsorption pipeline is arranged on each SRG flue gas pipeline of a reason SRG flue gas treatment system and connected with an inlet of a booster fan, an electric cut-off valve is arranged on the inlet of the booster fan, and a first manual cut-off valve is arranged on each re-adsorption pipeline; in addition, the two discharging pipelines are communicated and utilized through the overpressure transmitter and the electric stop valve. When an acid making system breaks down, the system can be automatically switched to a re-adsorption mode, SRG gas is guided to the first-stage adsorption tower for secondary adsorption treatment, and continuity and high efficiency of waste gas treatment are ensured. Meanwhile, a nitrogen purging belt and an electric heating belt are arranged, so that the pipeline is prevented from being corroded. According to the SRG flue gas treatment device, the SRG flue gas treatment efficiency is improved, and potential safety hazards in the waste gas treatment process are reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of industrial waste gas treatment, and specifically relates to a repeated adsorption treatment system for SRG flue gas in a sintering flue gas desulfurization and denitrification process. Background Art

[0002] With the rapid development of industrialization, environmental protection and safe production have become the focus of attention of enterprises and society. In current industrial production, desulfurization and denitrification technologies are widely used to reduce the emission of sulfur oxides and nitrogen oxides in flue gas, thereby effectively improving the quality of the atmospheric environment. The desulfurization and denitrification system adopted by our company, as an important part of environmental protection, aims to reduce the content of harmful substances in flue gas and ensure the green and efficient production process.

[0003] However, in actual operation, the industry generally adopts a treatment mode in which two desulfurization and denitrification systems share one acid production system. This design mode may improve efficiency, but it brings potential risks to production safety. Once the acid production system fails to shut down in time, the accident will be aggravated; and shutting down the acid production system will cause the following problems: (1) If the acid production system fails to shut down in time, SRG gas may overflow. SRG gas is a harmful substance. Its overflow will not only pollute the surrounding environment, but also touch the red line of production safety and cause major environmental pollution accidents. (2) The shutdown of the acid production system will also directly affect the normal operation of the desorption tower. The desorption tower is a key equipment in the desulfurization and denitrification process, responsible for desorption of sulfides on the activated carbon. Once the acid production system stops working, the desorption tower will lose its desorption function, resulting in a sharp increase in the total sulfur content on the activated carbon. The high sulfur content of activated carbon will greatly reduce the effect of flue gas purification. In severe cases, it may cause the flue gas purification to fail to meet the standards, thereby affecting the normal operation of the sintering machine, and even having to stop production to deal with it. (3) Excessive total sulfur content in activated carbon may also cause serious accidents such as "flying temperature fire". Under certain conditions, high-sulfur activated carbon may reach its auto-ignition point, causing a sharp rise in local temperature, which will not only damage the equipment, but may also cause fires, posing a threat to production safety. (4) Long-term acid production system failures may also cause corrosion and perforation of the desorption tower itself. Due to the lack of necessary maintenance, the desorption tower may suffer from corrosion and eventually perforation under the continuous influence of the acidic environment, which will not only affect the life of the equipment, but may also lead to the collapse of the entire desulfurization and denitrification system.

[0004] In summary, once the acid production system fails, due to the interdependence between systems, it is impossible to shut down for maintenance in time, which may lead to a chain reaction of accidents, causing the problem to expand rapidly and affect the stability and safety of the production line. In order to ensure the stability and safety of the production line, it is necessary to optimize and improve the existing system configuration to reduce potential failure risks and ensure production safety and environmental protection. Utility Model Content

[0005] In view of the many problems existing in the prior art regarding the failure of the existing SRG flue gas in the acid-making system, the utility model provides a repeated adsorption treatment system for the SRG flue gas in the sintering flue gas desulfurization and denitrification process.

[0006] To achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a repeated adsorption treatment system for SRG flue gas in the desulfurization and denitrification process of sintering flue gas, including two desulfurization and denitrification systems and an acid making system, the two desulfurization and denitrification systems have the same structure, and both include a primary adsorption tower, a secondary adsorption tower, a chimney, and a desorption tower, the flue gas outlet of the primary adsorption tower is connected to the flue gas inlet of the secondary adsorption tower through a flue gas pipeline, the flue gas outlet of the secondary adsorption tower is connected to the chimney through an exhaust pipeline, the flue gas inlet of the primary adsorption tower is connected to the inlet of a booster fan, the inlet of the booster fan is externally connected to the flue gas discharge port of the sintering machine, the depleted sulfur outlet of the secondary adsorption tower is connected to the depleted sulfur inlet of the primary adsorption tower through a first section of the depleted sulfur pipeline, the depleted sulfur outlet of the primary adsorption tower is connected to the depleted sulfur inlet of the desorption tower through a second section of the depleted sulfur pipeline, and the rich sulfur outlet of the desorption tower is connected to the secondary adsorption tower through a rich sulfur pipeline The sulfur-rich inlet of the tower is connected, and the gas phase outlet of the analysis tower transports the SRG gas to the purification process scrubber of the acid-making system through the SRG flue gas pipeline for primary reverse injection to participate in the acid-making process. A first electrically-controlled shut-off valve is arranged on the SRG flue gas pipeline. The tail gas discharge port of the acid-making system is connected to the inlet of the booster fan through the discharge pipeline. A second electrically-controlled shut-off valve is arranged on the tail gas discharge port of the acid-making system. A re-adsorption pipeline is arranged on the SRG flue gas pipeline and is connected to the inlet of the booster fan. An electric shut-off valve is arranged on the inlet of the booster fan. The re-adsorption pipeline is located on the left side of the first electrically-controlled shut-off valve. A first manual shut-off valve is arranged on the re-adsorption pipeline. When a fault occurs in the acid-making system, the first electrically-controlled shut-off valve and the second electrically-controlled shut-off valve are closed and the first manual shut-off valve is opened, so that the SRG gas is transported to the primary adsorption tower under the negative pressure of the booster fan for adsorption treatment.

[0007] As a further supplement to the above technical solution, a second manual shut-off valve is arranged on the re-adsorption pipeline, a purge bypass pipeline is bridged across both ends of the second manual shut-off valve, a nitrogen purge pipeline is arranged on the purge bypass pipeline, a third manual shut-off valve and a pneumatic valve are respectively arranged on the nitrogen purge pipeline, and a first manual control valve and a second manual control valve are respectively arranged on the purge bypass pipelines on both sides of the nitrogen purge pipeline.

[0008] As a further supplement to the above technical solution, electric heating tapes are respectively wrapped around the purge bypass pipe and the re-adsorption pipe near the second manual shut-off valve. The electric heating tapes maintain the pipe wrapped with the electric heating tapes at above 150°C to prevent the SRG gas from generating condensed acid to corrode the pipe.

[0009] As a further supplement to the above technical solution, a condensate discharge pipe is provided on the SRG flue gas pipe located on the left side of the first electrically controlled shut-off valve, the condensate discharge pipe is connected to the waste acid tank, and a condensate drain valve is provided on the condensate discharge pipe.

[0010] As a further supplement to the above technical solution, pressure transmitters are respectively provided on the flue gas inlets of the two primary adsorption towers, and the two emission pipes are connected. The two electric shut-off valves use the pressure transmitter to form a chain control through the on-site DCS control system. When any one of the booster fans fails, the electric shut-off valve is controlled to allow the SRG gas to enter the primary adsorption tower through the emission pipe under the negative pressure of the other booster fan, thereby realizing the mutual utilization of the two emission pipes.

[0011] As a further supplement to the above technical solution, a pressure gauge, a temperature gauge and a manual shut-off valve are respectively installed on the gas phase outlet of each of the analytical towers to ensure the safe and normal operation of each repeated adsorption treatment system.

[0012] Compared with the previous modification, the utility model has the following advantages:

[0013] 1. The utility model realizes emergency treatment when the acid production system fails through clever pipeline design and valve control. When the acid production system fails, the relevant valves can be quickly closed to guide the SRG gas to the re-adsorption pipeline for adsorption treatment, avoiding further impact on the acid production system, while also ensuring the effective treatment of SRG gas and maintaining the stability of the production environment. The repeated adsorption treatment system of the utility model realizes efficient and safe treatment of SRG gas through clever design and effective control, improves the stability and reliability of the production process, and also extends the service life of the equipment, reduces production costs, and has significant economic and social benefits.

[0014] 2. The utility model adds a nitrogen purge solution to the re-adsorption pipeline, which effectively solves the pipeline corrosion problem caused by the residual SRG gas in the re-adsorption pipeline after the acid production system returns to normal. Through nitrogen purge, the residual gas in the pipeline can be quickly emptied, ensuring the safe operation of the pipeline and extending the service life of the pipeline.

[0015] 3. In response to the corrosion problem of the re-adsorption pipeline, the utility model adopts two measures for protection: electric heating belt and condensation discharge pipeline. The electric heating belt can effectively prevent SRG gas from generating condensed acid in the pipeline, thereby avoiding corrosion of the pipeline; while the condensation discharge pipeline can discharge the generated condensed acid in time to prevent damage to the pipeline. These two measures together enhance the anti-corrosion ability of the pipeline and ensure the normal operation of the pipeline.

[0016] 4. The utility model also realizes the intercommunication between the two desulfurization and denitrification systems through the interlocking control of the pressure transmitter and the electric shut-off valve. This design not only improves the flexibility of the system, but also enhances the stability of the system. When any booster fan fails, the other booster fan can quickly take over the processing task, ensuring the continuous processing of SRG gas and reducing the risk of production interruption. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of the repeated adsorption treatment system in the utility model.

[0018] In the figure: the desulfurization and denitrification system is 100, the acid making system is 200, the electric heating belt is 300, the primary adsorption tower is 1, the secondary adsorption tower is 2, the chimney is 3, the analysis tower is 4, the booster fan is 5, the SRG flue gas duct is 6, the discharge duct is 7, the first electric control shut-off valve is 8, the second electric control shut-off valve is 9, the re-adsorption duct is 10, the electric shut-off valve is 11, the first manual shut-off valve is 12, the second manual shut-off valve is 13, the purge bypass duct is 14, the nitrogen purge duct is 15, the third manual shut-off valve is 16, the pneumatic valve is 17, the first manual control valve is 18, the second manual control valve is 19, the condensate discharge duct is 20, the condensate drain valve is 21, the pressure transmitter is 22, the pressure gauge is 23, the temperature gauge is 24, and the manual shut-off valve is 25. DETAILED DESCRIPTION

[0019] In order to further illustrate the technical solution of the utility model, the following Figure 1 , we further illustrate the utility model through four embodiments according to the on-site transformation implementation situation.

[0020] As attached Figure 1As shown, in the existing sintering flue gas desulfurization and denitrification process, the SRG flue gas treatment system is as follows: it includes two desulfurization and denitrification systems 100 and an acid making system 200, the two desulfurization and denitrification systems 100 have the same structure, and both include a primary adsorption tower 1, a secondary adsorption tower 2, a chimney 3, and a desorption tower 4, the flue gas outlet of the primary adsorption tower 1 is connected to the flue gas inlet of the secondary adsorption tower 2 through a flue gas pipeline, the flue gas outlet of the secondary adsorption tower 2 is connected to the chimney 3 through an exhaust pipeline, the flue gas inlet of the primary adsorption tower 1 is connected to the inlet of a booster fan 5, the inlet of the booster fan 5 is externally connected to the flue gas discharge port of the sintering machine, and the secondary adsorption tower The sulfur-poor outlet of the first adsorption tower 2 is connected to the sulfur-poor inlet of the first adsorption tower 1 through the first section of the sulfur-poor pipeline, the sulfur-poor outlet of the first adsorption tower 1 is connected to the sulfur-poor inlet of the desorption tower 4 through the second section of the sulfur-poor pipeline, the sulfur-rich outlet of the desorption tower 4 is connected to the sulfur-rich inlet of the second adsorption tower 2 through the sulfur-rich pipeline, the gas phase outlet of the desorption tower 4 is connected to the scrubber inlet through the SRG flue gas pipeline 6, and the first electrically controlled shut-off valve 8 is arranged on the SRG flue gas pipeline 6, the tail gas discharge port of the acid-making system 200 is connected to the inlet of the booster fan 5 through the discharge pipeline 7, and the second electrically controlled shut-off valve 9 is arranged on the tail gas discharge port of the acid-making system 200. In the normal production process, the SRG gas from the desorption tower is transported to the scrubber of the purification process of the acid-making system 200 for the first-level reverse injection to participate in the acid-making process. Embodiment 1

[0021] As attached Figure 1 As shown, a repeated adsorption treatment system, based on the above-mentioned SRG flue gas treatment system, we set a re-adsorption pipeline 10 on the SRG flue gas pipeline 6 to connect with the inlet of the booster fan 5, and an electric shut-off valve 11 is set on the inlet of the booster fan 5. The re-adsorption pipeline 10 is located on the left side of the first electric control shut-off valve 8, and a first manual shut-off valve 12 is set on the re-adsorption pipeline 10. In this embodiment, once the acid-making system 200 fails, we isolate the acid-making system 200 by closing the first electric control shut-off valve 8 and the second electric control shut-off valve 9, and open the first manual shut-off valve 12 at the same time, so that the SRG gas coming out of the analysis tower 4 is transported to the primary adsorption tower 1 for adsorption treatment under the negative pressure of the booster fan 5. Of course, in order to ensure the safe and normal operation of each repeated adsorption treatment system, we install pressure gauges 23, temperature gauges 24, manual shut-off valves 25 and other instrumentation equipment on the gas phase outlet of each of the analysis towers 4, so that on-site personnel can observe and control the entire treatment system on the spot. Embodiment 2

[0022] After the acid production system returns to normal, the SRG gas is stopped from continuing to pass through the re-adsorption pipeline. We open the first electrically controlled shut-off valve and the second electrically controlled shut-off valve to allow the SRG gas from the analysis tower to be transported to the purification process scrubber of the acid production system to continue to participate in the acid production process. At the same time, the first manual shut-off valve is closed. At this time, the SRG gas remaining in the re-adsorption pipeline will corrode the pipeline if it is not emptied in time.

[0023] Therefore, in order to prevent the above situation from happening, we have added a nitrogen purge solution. Figure 1 As shown, a second manual shut-off valve 13 is provided on the re-adsorption pipeline 10, a purge bypass pipeline 14 is connected across both ends of the second manual shut-off valve 13, a nitrogen purge pipeline 15 is provided on the purge bypass pipeline 14, a third manual shut-off valve 16 and a pneumatic valve 17 are respectively provided on the nitrogen purge pipeline 15, and a first manual control valve 18 and a second manual control valve 19 are respectively provided on the purge bypass pipeline 14 located on both sides of the nitrogen purge pipeline 15.

[0024] When the acid-making system returns to normal, we first close the second manual shut-off valve 13, open the third manual shut-off valve 16 and the pneumatic valve 17, the first electric-controlled shut-off valve 8 and the second electric-controlled shut-off valve 9, and use nitrogen to purge all the SRG gas remaining in the re-adsorption pipeline 10; then close the first manual shut-off valve 12, the first electric-controlled shut-off valve 8 and the second electric-controlled shut-off valve 9, and finally close the third manual shut-off valve 16 and the pneumatic valve 17. Thus, the nitrogen purge operation is completed. Embodiment 3

[0025] After the repeated adsorption treatment system was put into operation for a period of time, we found that the re-adsorption pipes near the SRG flue gas pipe and the purge bypass pipe section of the acid production system had different degrees of wear. Figure 1 As shown, we take different measures: on the one hand, electric heating belts 300 are respectively wound around the purge bypass pipe 14 and the re-adsorption pipe 10 near the second manual shut-off valve 13, and the electric heating belts 300 keep the pipes wound around the electric heating belts 300 at above 150°C to prevent the SRG gas from generating condensed acid to corrode the pipes. On the other hand, a condensation discharge pipe 20 is arranged on the SRG flue gas pipe 6 on the left side of the first electric-controlled shut-off valve 8, and the condensation discharge pipe 20 is connected to the waste acid pool, and a condensation drain valve 21 is arranged on the condensation discharge pipe 20. Embodiment 4

[0026] Since this renovation involves a treatment mode in which two desulfurization and denitrification systems share one acid production system, it is also crucial to use the two desulfurization and denitrification systems to achieve mutual treatment of the SRG gases analyzed by the two desulfurization and denitrification systems. Such a design helps to increase the stability of the entire system operation.

[0027] As attached Figure 1 As shown, we respectively set pressure transmitters 22 on the flue gas inlets of the two primary adsorption towers 1, and the two exhaust pipes 7 are connected. The two electric shut-off valves 11 use the pressure transmitter 22 to form a chain control through the on-site DCS control system. When any one of the booster fans 5 fails, the electric shut-off valve 11 is controlled to allow the SRG gas to enter the primary adsorption tower 1 through the exhaust pipe 7 under the negative pressure of the other booster fan 5, thereby realizing the mutual use of the two exhaust pipes 7.

[0028] In summary, the transformation of this project cleverly utilized pipeline design and valve control to achieve emergency treatment when the acid production system fails, improving the stability and reliability of the production process. At the same time, the repeated adsorption treatment system, through clever design and effective control, achieved efficient and safe treatment of SRG gas, extended the service life of the equipment, reduced production costs, and had significant economic and social benefits.

[0029] At the same time, the project transformation solved the safety hazards brought about by the treatment mode of two desulfurization and denitrification systems sharing one acid production system, avoided the overflow of SRG gas and the sharp increase in the total sulfur content on the activated carbon, ensured the stability of the production environment, and improved the safety and environmental protection of the production process.

[0030] Before the transformation plan was put into use, the analytical tower was perforated due to the shutdown of the acid production plant due to a fault. It took 6 days to replace the analytical tower, with equipment costs of 4 million yuan and construction costs of 270,000 yuan, affecting the profit of sintered ore by 5.1 million yuan. This device is the first SRG gas recycling process device for activated carbon desulfurization and denitrification, which can effectively obtain maintenance time for acid production. It is the first and only application of activated carbon desulfurization and denitrification in the country.

[0031] The above shows and describes the main features and advantages of the utility model. For those skilled in the art, it is obvious that the specific implementation of the utility model is not limited to the details of the above exemplary embodiments, and the creative ideas and design ideas of the utility model can be realized in other specific forms without departing from the spirit or basic features of the utility model, which should be equivalent to the protection scope disclosed in the technical solution of the utility model. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the utility model is limited by the attached claims rather than the above description, so it is intended to include all changes that fall within the meaning and scope of the equivalent elements of the claims in the utility model.

[0032] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A repeated adsorption treatment system for SRG flue gas in a sintering flue gas desulfurization and denitrification process, comprising two desulfurization and denitrification systems (100) and an acid production system (200), wherein the two desulfurization and denitrification systems (100) have the same structure and both comprise a primary adsorption tower (1), a secondary adsorption tower (2), a chimney (3), and a desorption tower (4), wherein the flue gas outlet of the primary adsorption tower (1) is connected to the flue gas inlet of the secondary adsorption tower (2) through a flue gas pipeline, the flue gas outlet of the secondary adsorption tower (2) is connected to the chimney (3) through an exhaust pipeline, the flue gas inlet of the primary adsorption tower (1) is connected to the inlet of a booster fan (5), the inlet of the booster fan (5) is externally connected to the flue gas discharge port of a sintering machine, and the desulfurized outlet of the secondary adsorption tower (2) is connected to a first section of the desulfurized outlet through a first section of the desulfurized outlet. The sulfur-poor inlet of the first-stage adsorption tower (1) is connected, the sulfur-poor outlet of the first-stage adsorption tower (1) is connected to the sulfur-poor inlet of the desorption tower (4) through the second section of the sulfur-poor pipeline, the sulfur-rich outlet of the desorption tower (4) is connected to the sulfur-rich inlet of the second-stage adsorption tower (2) through the sulfur-rich pipeline, the gas phase outlet of the desorption tower (4) transports the SRG gas to the purification process scrubber of the acid production system (200) through the SRG flue gas pipeline (6) to perform the first-stage reverse injection to participate in the acid production process, a first electrically controlled shut-off valve (8) is arranged on the SRG flue gas pipeline (6), the tail gas discharge port of the acid production system (200) is connected to the inlet of the booster fan (5) through the discharge pipeline (7), and a second electrically controlled shut-off valve (9) is arranged on the tail gas discharge port of the acid production system (200), characterized in that: A re-adsorption pipeline (10) is provided on the SRG flue gas pipeline (6) and is connected to the inlet of the booster fan (5). An electric shut-off valve (11) is provided on the inlet of the booster fan (5). The re-adsorption pipeline (10) is located on the left side of the first electric-controlled shut-off valve (8). A first manual shut-off valve (12) is provided on the re-adsorption pipeline (10). When a fault occurs in the acid-making system (200), the first electric-controlled shut-off valve (8) and the second electric-controlled shut-off valve (9) are closed and the first manual shut-off valve (12) is opened, so that the SRG gas is transported to the first-level adsorption tower (1) for adsorption treatment under the negative pressure of the booster fan (5).

2. The repeated adsorption treatment system for SRG flue gas in the sintering flue gas desulfurization and denitrification process according to claim 1 is characterized by: A second manual shutoff valve (13) is provided on the re-adsorption pipeline (10); a purge bypass pipeline (14) is connected across both ends of the second manual shutoff valve (13); a nitrogen purge pipeline (15) is provided on the purge bypass pipeline (14); a third manual shutoff valve (16) and a pneumatic valve (17) are respectively provided on the nitrogen purge pipeline (15); and a first manual control valve (18) and a second manual control valve (19) are respectively provided on the purge bypass pipelines (14) located on both sides of the nitrogen purge pipeline (15).

3. The repeated adsorption treatment system for SRG flue gas in the sintering flue gas desulfurization and denitrification process according to claim 2 is characterized by: Electric heating tapes (300) are respectively wound around the purge bypass pipeline (14) and the re-adsorption pipeline (10) near the second manual shut-off valve (13), and the electric heating tapes (300) maintain the pipeline wound around the electric heating tapes (300) at a temperature above 150° C., so as to prevent the SRG gas from generating condensed acid that corrodes the pipeline.

4. A repeated adsorption treatment system for SRG flue gas in a sintering flue gas desulfurization and denitrification process according to any one of claims 1 to 3, characterized in that: A condensate discharge pipe (20) is provided on the SRG flue gas pipe (6) located on the left side of the first electrically controlled shut-off valve (8); the condensate discharge pipe (20) is connected to the waste acid tank; and a condensate drain valve (21) is provided on the condensate discharge pipe (20).

5. The repeated adsorption treatment system for SRG flue gas in the sintering flue gas desulfurization and denitrification process according to claim 4 is characterized by: Pressure transmitters (22) are respectively provided at the flue gas inlets of the two primary adsorption towers (1), and the two exhaust pipes (7) are connected. The two electric shut-off valves (11) form interlocking control through the on-site DCS control system by utilizing the pressure transmitters (22). When any one of the booster fans (5) fails, the electric shut-off valves (11) are controlled to allow the SRG gas to enter the primary adsorption tower (1) through the exhaust pipe (7) under the negative pressure of the other booster fan (5), thereby realizing the interconnection and utilization of the two exhaust pipes (7).

6. A repeated adsorption treatment system for SRG flue gas in a sintering flue gas desulfurization and denitrification process according to any one of claims 1 to 3 or 5, characterized in that: A pressure gauge (23), a temperature gauge (24), and a manual shut-off valve (25) are respectively installed at the gas phase outlet of each of the analytical towers (4) to ensure the safe and normal operation of each repeated adsorption treatment system.

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