High-temperature desulfurization, denitrification and dust removal integrated equipment
The integrated high-temperature desulfurization, denitrification and dust removal equipment has solved the problems of equipment corrosion and blockage caused by low-temperature treatment, achieving stable operation and high energy efficiency, and reducing operating costs and carbon emissions.
Patent Information
- Application Number
- CN202423120545.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-17
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-12-17
AI Technical Summary
Existing boiler flue gas treatment technologies, such as low-temperature dust removal, denitrification, and desulfurization, suffer from problems such as flue gas corrosion and blockage, high energy consumption, and secondary pollution.
The system employs an integrated high-temperature desulfurization, denitrification, and dust removal device, which includes an economizer, flue gas temperature control device, desulfurization system, dust collector, and air preheater. The flue gas undergoes SCR denitrification in the high-temperature section, and through dry desulfurization and high-temperature bag filter dust removal, the flue gas temperature is regulated within the range of 180-280℃, achieving integrated treatment.
It improves equipment operational stability, reduces operating costs, reduces carbon emissions, improves the overall thermal efficiency of the boiler, and avoids equipment corrosion and blockage.
Smart Images
Figure CN223530197U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of boiler flue gas treatment technology, and in particular to an integrated high-temperature desulfurization, denitrification and dust removal device. Background Technology
[0002] Existing boiler flue gas treatment methods mostly employ low-temperature treatment. Low-temperature dust removal, denitrification, and desulfurization primarily fall into two categories: One involves adding a catalyst within a flue gas temperature range of approximately 350°C to remove NOx and meet emission standards. The gas then enters a heat exchanger for heat exchange, and after heat exchange, the flue gas temperature is between 120 and 160°C before entering a dust collector for dust removal, followed by desulfurization in a desulfurization tower. Once the flue gas achieves ultra-clean emission standards, it is then discharged into the atmosphere through a chimney. The other method involves adding a catalyst within a flue gas temperature range of approximately 350°C to remove NOx and meet emission standards. The gas then enters a heat exchanger for heat exchange, and after heat exchange, the flue gas temperature is between 120 and 160°C before undergoing semi-dry desulfurization (achieving a sulfur content of 35 mg / Nm³). 3 After that, it enters the dust collector for dust removal (dust concentration reaches 5mg / Nm³). 3 (The following), and then enters the chimney and is discharged into the atmosphere.
[0003] The problems with low-temperature dust removal, desulfurization, and denitrification are as follows:
[0004] 1. Problems caused by denitrification: After a large amount of ammonia is injected, the sulfur in the flue gas reacts with ammonia to produce ammonium bisulfate, which causes significant corrosion to the flue gas heat exchanger and affects the operation of the equipment.
[0005] 2. Impact of dust removal: In the temperature range of 120-160℃, the flue gas contains a large amount of moisture, which condenses into water at low temperatures and combines with ash to form mud, clogging heat exchangers and dust collectors, leading to frequent equipment accidents.
[0006] 3. Impacts of desulfurization: Low-temperature desulfurization using ammonia desulfurization results in significant heat loss, high energy consumption, high flue gas temperature, and low overall efficiency. Semi-dry desulfurization, on the other hand, generates large amounts of wastewater, incurring high treatment costs and causing secondary pollution to the environment. Utility Model Content
[0007] The purpose of this invention is to provide an integrated high-temperature desulfurization, denitrification, and dust removal device to solve the problems existing in the prior art, reduce the corrosion of heat exchange equipment by flue gas, and enable the heat exchange equipment after the dust collector to operate continuously and stably. This device improves the operational stability of the device and the overall thermal efficiency of the boiler, reduces operating costs, and reduces carbon emissions.
[0008] To achieve the above objectives, this utility model provides the following solution: This utility model provides an integrated high-temperature desulfurization, denitrification, and dust removal device, including an economizer, a flue gas temperature regulating device, a desulfurization system, a dust collector, and an air preheater. The economizer is installed on the boiler's flue gas exhaust pipe. The high-temperature section of the economizer is equipped with a catalyst for flue gas denitrification, and the low-temperature section of the economizer is connected to the flue gas temperature regulating device. The outlet of the boiler's flue gas exhaust pipe is connected to the desulfurization system, which adopts dry desulfurization. The exhaust end of the desulfurization system is sequentially equipped with the dust collector and the air preheater. After the flue gas is dedusted by the dust collector, it enters the air preheater for heat exchange before entering the chimney or cooling tower for discharge.
[0009] In one embodiment, the flue gas outlet temperature of the high-temperature section of the economizer is set to 350-370°C, and the flue gas temperature of the low-temperature section of the economizer is 240°C.
[0010] In one embodiment, the smoke temperature regulating device is used to mix cold air with the smoke in the exhaust duct to regulate the temperature of the smoke in the exhaust duct, and the smoke temperature regulating device regulates the temperature of the smoke in the exhaust duct to 180-280°C.
[0011] In one embodiment, the smoke temperature regulating device is a fan.
[0012] In one embodiment, the desulfurization system employs a desulfurization tower, and powdered sodium bicarbonate is used as the desulfurization medium inside the desulfurization tower.
[0013] In one embodiment, the dust collector is a high-temperature bag filter, which removes NOx and dust from the flue gas.
[0014] In one embodiment, the dust collector is a high-temperature denitrification filter bag dust collector, which removes NOx and dust from the flue gas.
[0015] In one embodiment, the flue gas after dust removal by the dust collector enters the air preheater for heat exchange at a temperature range of 180-280°C, and the temperature of the flue gas after heat exchange in the air preheater drops to below 120°C.
[0016] In one embodiment, a low-temperature economizer is also provided on the outlet side of the air preheater. The flue gas enters the low-temperature economizer for heat exchange after passing through the air preheater. The temperature of the flue gas after heat exchange in the low-temperature economizer is below 80°C.
[0017] The present invention achieves the following beneficial technical effects compared to the prior art:
[0018] This utility model discloses an integrated high-temperature desulfurization, denitrification, and dust removal device, comprising an economizer, a flue gas temperature regulation device, a desulfurization system, a dust collector, and an air preheater. Flue gas undergoes heat exchange in the high-temperature section of the economizer, with a designed outlet temperature of approximately 350–370°C. Within this approximately 350°C range, a catalyst is added for SCR denitrification. After denitrification, the gas enters the low-temperature section of the economizer for further heat exchange, with an outlet temperature of approximately 240°C. A flue gas temperature regulation device is then added to adjust the flue gas temperature within the flue duct to a range of 180–280°C. The flue gas then enters the desulfurization system through the boiler flue outlet for desulfurization, achieving a concentration of <30 mg / m³. 3 The flue gas then enters the dust collector, where NOx and dust are removed by bag filtration to meet ultra-low emission standards. The flue gas, ranging from 180 to 280°C, then enters the air preheater for heat exchange before being discharged into the atmosphere through a chimney or cooling tower. This equipment improves the operational stability of the unit and the overall thermal efficiency of the boiler, reduces operating costs, and decreases carbon emissions. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is an overall layout diagram of the integrated high-temperature desulfurization, denitrification, and dust removal equipment.
[0021] Among them, 1. Economizer; 2. Fly ash discharge outlet; 3. Desulfurization system; 4. Dust collector; 5. Air preheater; 6. Low temperature economizer; 7. Chimney; 8. Flue gas duct. Detailed Implementation
[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0023] The purpose of this invention is to provide an integrated high-temperature desulfurization, denitrification, and dust removal device to solve the problems existing in the prior art, reduce the corrosion of heat exchange equipment by flue gas, and enable the heat exchange equipment after the dust collector to operate continuously and stably. This device improves the operational stability of the device and the overall thermal efficiency of the boiler, reduces operating costs, and reduces carbon emissions.
[0024] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0025] like Figure 1 As shown, this utility model provides an integrated high-temperature desulfurization, denitrification, and dust removal device, including an economizer 1, a flue gas temperature regulating device, a desulfurization system 3, a dust collector 4, and an air preheater 5. The economizer 1 is installed on the boiler's exhaust pipe 8. The high-temperature section of the economizer 1 is equipped with a catalyst for flue gas denitrification, and the low-temperature section of the economizer 1 is connected to the flue gas temperature regulating device. The outlet of the boiler's exhaust pipe 8 is connected to the desulfurization system 3, which employs dry desulfurization. The exhaust end of the desulfurization system 3 is sequentially equipped with a dust collector 4 and an air preheater 5. After dust removal by the dust collector 4, the flue gas enters the air preheater 5 for heat exchange before entering the chimney 7 or cooling tower for discharge. The flue gas outlet temperature of the high-temperature section of the economizer 1 is set to 350-370℃, and the flue gas temperature of the low-temperature section of the economizer 1 is 240℃. The flue gas temperature regulating device is used to mix cold air with the flue gas in the flue gas duct 8 to regulate the flue gas temperature in the flue gas duct 8. The flue gas temperature regulating device regulates the flue gas temperature in the flue gas duct 8 to 180-280℃. Fly ash discharge outlets 2 are provided at the end of the flue gas duct 8, the end of the desulfurization system 3, and the end of the dust collector 4.
[0026] In one embodiment, the flue gas originates from a boiler. After ammonia injection (SNCR) for denitrification at high temperature, the flue gas then passes through the high-temperature section of economizer 1 for heat exchange. The outlet temperature of the high-temperature section of economizer 1 is designed to be approximately 350–370°C. A catalyst is added within this approximately 350°C range for SCR denitrification. The flue gas then enters the low-temperature section of economizer 1 for heat exchange, with an outlet temperature of approximately 240°C. A flue gas temperature regulation device is then added (using a mixture of cold air and hot flue gas for regulation, for example, by installing a fan on the exhaust duct 8 to introduce cold air to cool the hot flue gas) to regulate the flue gas temperature within the flue, adjusting it to a range of 180–280°C. The flue gas then enters the desulfurization system 3 for desulfurization (NaHCO3—baking soda is injected into the desulfurization tower or flue) to achieve a concentration of <30 mg / m³. 3 The flue gas then enters the bag filter 4 (using high-temperature bags), where NOx and dust are removed through bag filtration to achieve ultra-low emission standards. The flue gas, with a temperature range of 180-280°C, enters the air preheater 5 for heat exchange (the flue gas temperature drops below 120°C), and then enters the low-temperature economizer 6 for heat exchange (the flue gas temperature drops below 80°C). Finally, the flue gas enters the chimney 7 or cooling tower and is discharged into the atmosphere.
[0027] When the flue gas temperature is above 160℃, SO2 has very little corrosive effect on the equipment, or even no corrosive effect at all. After sulfur, nitrates, and dust are removed from the flue gas, heat exchange is performed again at a flue gas temperature of 180-280℃. At this temperature, the sulfur, nitrate, and dust content in the flue gas is high, which reduces the corrosion problem of the flue gas on the heat exchange equipment. This allows the heat exchange equipment after dust collector 4 to operate continuously and stably, solving the impact of low-temperature dust removal on the equipment. This process improves the stable operation of the equipment and the overall thermal efficiency of the boiler, reduces operating costs, and reduces carbon emissions.
[0028] In one embodiment, desulfurization system 3 employs a desulfurization tower, within which powdered sodium bicarbonate is used as the desulfurization medium. The dry desulfurization system uses sodium bicarbonate (NaHCO3) as the desulfurizing agent. NaHCO3 reacts with SO2, SO3, and other acidic gases such as HCl in the flue gas to produce Na2SO4 and NaCl. The reaction principle is as follows:
[0029] 2NaHCO3 + SO3 = Na2SO4 + H2O + 2CO2
[0030] 2NaHCO3+1 / 2O2+SO2=Na2SO4+H2O+2CO2
[0031] NaHCO3 + HCl = NaCl + H2O + CO2;
[0032] Dry desulfurization produces no desulfurization wastewater, making desulfurization simpler and more efficient.
[0033] In another embodiment, the flue gas originates from the boiler. Ammonia injection (SNCR) is used for denitrification in the high-temperature flue gas. After heat exchange in the high-temperature section of economizer 1, the flue gas outlet temperature in the high-temperature and low-temperature sections of economizer 1 is approximately 180–280°C. A flue gas temperature regulating device (using a mixture of cold air and hot flue gas for regulation) is added to regulate the flue gas temperature within the flue, maintaining it within the range of 180–280°C. The flue gas then enters the desulfurization system 3 through the boiler flue outlet for desulfurization (NaHCO3—baking soda is injected in the desulfurization tower or flue) to reduce the nitrogen content to <30 mg / m³. 3 The flue gas then enters the bag filter 4 (using high-temperature denitrification filter bags), where NOx and dust are removed by the filter bags, achieving ultra-low emission standards. The flue gas, with a temperature range of 180-280°C, enters the air preheater 5 for heat exchange (the flue gas temperature drops below 120°C), and then enters the low-temperature economizer 6 for heat exchange (the flue gas temperature drops below 80°C). Finally, the flue gas enters the chimney 7 or cooling tower and is discharged into the atmosphere.
[0034] The dust collector 4 adopts a high-temperature denitrification filter bag dust collector 4, which removes NOx and dust from the flue gas, reducing the investment and operating costs of environmental protection.
[0035] Denitrification filter bag principle:
[0036] 4NO + 4NH3 + O2 = 4N2 + 6H2O
[0037] 4NO2 + 8NH3 + 2O2 = 6N2 + 12H2O.
[0038] It should be noted that, for those skilled in the art, it is obvious that this utility model is not limited to the details of the above exemplary embodiments, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this utility model. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this utility model is defined by the appended claims rather than the foregoing description. Therefore, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this utility model, and no reference numerals in the claims should be construed as limiting the scope of the claims.
[0039] This utility model uses specific examples to illustrate its principles and implementation methods. The above description of the embodiments is only for the purpose of helping to understand the method and core idea of this utility model. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the idea of this utility model. In summary, the content of this specification should not be construed as a limitation of this utility model.
Claims
1. A high-temperature desulfurization, denitrification, and dust removal integrated equipment, characterized in that: The system includes an economizer, a flue gas temperature control device, a desulfurization system, a dust collector, and an air preheater. The economizer is installed on the boiler's flue gas exhaust pipe. The high-temperature section of the economizer is equipped with a catalyst for flue gas denitrification, and the low-temperature section of the economizer is connected to the flue gas temperature control device. The outlet of the boiler's flue gas exhaust pipe is connected to the desulfurization system, which uses dry desulfurization. The exhaust end of the desulfurization system is sequentially equipped with the dust collector and the air preheater. After the flue gas is dedusted by the dust collector, it enters the air preheater for heat exchange before entering the chimney or cooling tower for discharge.
2. The integrated high-temperature desulfurization, denitrification, and dust removal equipment according to claim 1, characterized in that: The flue gas outlet temperature of the high-temperature section of the economizer is set to 350-370℃, and the flue gas temperature of the low-temperature section of the economizer is 240℃.
3. The integrated high-temperature desulfurization, denitrification, and dust removal equipment according to claim 2, characterized in that: The smoke temperature regulating device is used to mix cold air with the smoke in the exhaust pipe to regulate the temperature of the smoke in the exhaust pipe. The smoke temperature regulating device regulates the temperature of the smoke in the exhaust pipe to 180-280℃.
4. The integrated high-temperature desulfurization, denitrification, and dust removal equipment according to claim 1, characterized in that: The smoke temperature regulating device uses a fan.
5. The integrated high-temperature desulfurization, denitrification, and dust removal equipment according to claim 1, characterized in that: The desulfurization system uses a desulfurization tower, and powdered baking soda is used as the desulfurization medium inside the desulfurization tower.
6. The integrated high-temperature desulfurization, denitrification, and dust removal equipment according to claim 1, characterized in that: The dust collector is a high-temperature bag filter, which removes NOx and dust from the flue gas.
7. The integrated high-temperature desulfurization, denitrification, and dust removal equipment according to claim 1, characterized in that: The dust collector is a high-temperature denitrification filter bag dust collector, which removes NOx and dust from the flue gas.
8. The integrated high-temperature desulfurization, denitrification, and dust removal equipment according to claim 1, characterized in that: The flue gas after dust removal by the dust collector enters the air preheater for heat exchange at a temperature range of 180-280℃. After heat exchange in the air preheater, the temperature of the flue gas drops to below 120℃.
9. The integrated high-temperature desulfurization, denitrification, and dust removal equipment according to claim 8, characterized in that: The air preheater is also equipped with a low-temperature economizer at its outlet. The flue gas enters the low-temperature economizer for heat exchange after passing through the air preheater. The temperature of the flue gas after heat exchange in the low-temperature economizer is below 80°C.