A dual cyclone burner and thermal oxidation device suitable for oxygen-containing tail gas

Abstract

A double cyclone burner and thermal oxidation device suitable for oxygen-containing tail gas relates to the field of environmental protection treatment of chemical waste, comprising a burner shell, the burner shell comprising a front end cover, a rear end cover, an inner shell, an outer shell and a partition plate, the outer shell being sleeved outside the inner shell, the two ends of the outer shell and the inner shell being connected with the front end cover and the rear end cover, the partition plate separating the space between the inner shell and the outer shell into an air cavity and an oxygen-containing tail gas cavity, the outer shell being provided with an air inlet communicating with the air cavity and an oxygen-containing tail gas inlet communicating with the oxygen-containing tail gas cavity, the inside of the inner shell being a mixing duct, one end of the inner shell penetrating out of the rear shell to form a burner outlet; an air cyclone device and a tail gas cyclone device being arranged in the inner shell and located on the two sides of the partition plate, the air cyclone device communicating the air cavity and the mixing duct, the tail gas cyclone device communicating the oxygen-containing tail gas cavity and the mixing duct; a liquid gun and a gas gun being connected with the front end cover and penetrating out of the inner shell to the burner outlet. The system operation flexibility and energy saving effect are improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of environmental protection treatment of chemical waste, and particularly relates to a double-cyclone burner and a thermal oxidation device suitable for oxygen-containing tail gas. BACKGROUND

[0002] The new HCN production process of the chemical industry and the maleic anhydride production process by n-butane oxidation method can produce a large amount of oxygen-containing tail gas, in which the oxygen volume fraction is 13% to 16%, and has a certain combustion-supporting effect. At the same time, the tail gas also contains acetic acid, propionic acid, n-butanol, HCN and CO and other substances, and has a certain heat value and toxicity, so the thermal oxidation method is the most economical and effective for incineration treatment and heat recovery. Therefore, the effective utilization of this kind of tail gas in the industrial field has been continuously explored.

[0003] The patent with the application number 202110074486.3 "Thermal oxidation incineration treatment burner, device and process for HCN-containing waste gas" introduces a device for treating HCN waste gas by incineration method, which mainly adopts the method of improving the operation flexibility of the burner to adapt to the adjustment requirements of complex working conditions such as large flow and high fluctuation of HCN waste gas, but the HCN device exhaust gas almost does not contain oxygen, and the waste gas has high heat value, and the waste gas adopts the way of opposite mixing, and the combustion effect needs to be improved, which is obviously different from the application scene of the present application. The patent with the application number 202211620540.0 "Process method for treating tail gas of RTO furnace of maleic anhydride device" introduces a kind of incineration device for treating maleic anhydride tail gas and liquid fuel by TO furnace and RTO furnace, in which the maleic anhydride tail gas is mainly oxidized and decomposed in the RTO furnace, and the TO furnace is mainly used for treating high heat value liquid fuel, and the system is energy-saving and efficient, but the operation is complex, the system stability is poor, and there is a problem of insufficient tail gas combustion. SUMMARY

[0004] The technical problem solved by the present application is to overcome the shortcomings of the prior art and provide a double-cyclone burner and a thermal oxidation device suitable for oxygen-containing tail gas. Through the double-cyclone design of the burner and the reasonable configuration of the materials, the operation flexibility and energy-saving effect of the system are improved. At the same time, the gradient-enhanced cyclone combustion technology is applied to improve the mixing and combustion effect of the large-flow oxygen-containing tail gas in the thermal oxidation furnace, realize low-nitrogen full combustion, and finally realize the standard emission of flue gas.

[0005] The technical scheme provided by the present application is as follows:

[0006] In a first aspect, a double-cyclone burner suitable for oxygen-containing tail gas is provided, which comprises a burner shell, an air cyclone, a tail gas cyclone, a liquid gun and a gas gun.

[0007] The burner housing includes a front cover, a rear cover, an inner housing, an outer housing, and a partition. The outer housing is fitted over the inner housing. The front cover and rear cover are connected to the two ends of the outer housing and the inner housing, respectively. The partition connects the inner housing and the outer housing and divides the space between them into an air chamber and an oxygen-containing exhaust gas chamber. The outer housing has an air inlet and an oxygen-containing exhaust gas inlet. The air inlet communicates with the air chamber, and the oxygen-containing exhaust gas inlet communicates with the oxygen-containing exhaust gas chamber. A mixing duct is formed inside the inner housing. The end of the inner housing away from the front housing extends out of the rear housing to form the burner outlet. An air cyclone and an exhaust gas cyclone are located in the inner housing and on both sides of the partition. The air cyclone communicates with the air chamber and the mixing duct, and the exhaust gas cyclone communicates with the oxygen-containing exhaust gas chamber and the mixing duct.

[0008] The liquid gun and gas gun are connected to the front cover and extend from inside the inner housing to the burner outlet.

[0009] The air cyclone and exhaust cyclone align the rotation direction of the airflow; both the air cyclone and exhaust cyclone include through holes and inclined blades on the outer casing, with the through holes located between adjacent inclined blades; the airflow passes between the inclined blades and then enters the mixing duct through the through holes, forming a rotating airflow.

[0010] The liquid gun and gas gun include a central liquid gun, an annular gas gun, a central gas gun, and a surrounding liquid gun. The central liquid gun and the central gas gun are coaxially combined, with the central gas gun sleeved outside the central liquid gun. The central gas gun and the surrounding liquid gun are arranged in concentric circles outside the central gas gun. The central liquid gun and the surrounding liquid gun are used to inject liquid fuel into the burner outlet, and the central gas gun and the annular gas gun are used to inject gaseous fuel into the burner outlet.

[0011] A flame stabilizer is fitted at the end of the central gas gun near the burner outlet, and a surrounding liquid gun is arranged outside the flame stabilizer, while an annular gas gun is arranged outside the surrounding liquid gun.

[0012] When the liquid fuel provides the heat source for combustion, air is introduced through the air inlet and oxygen-containing exhaust gas is introduced through the oxygen-containing exhaust gas inlet, using both air and oxygen-containing exhaust gas for dual combustion support; when the gas is used to provide the heat source for combustion, oxygen-containing exhaust gas is introduced through the oxygen-containing exhaust gas inlet and the air inlet is closed, using oxygen-containing exhaust gas for independent combustion support.

[0013] Secondly, a thermal oxidation device suitable for oxygen-containing exhaust gas is provided, comprising an oxidizer inlet, a primary exhaust gas chamber, a secondary exhaust gas chamber, a thermal oxidizer outlet, and a dual-swirl burner as described above suitable for oxygen-containing exhaust gas. The burner outlet of the burner shell is connected to the oxidizer inlet. The oxidizer inlet, the primary exhaust gas chamber, the secondary exhaust gas chamber, and the thermal oxidizer outlet are connected sequentially. The primary exhaust gas chamber is provided with a primary exhaust gas nozzle for injecting oxygen-containing exhaust gas into the primary exhaust gas chamber, and the secondary exhaust gas chamber is provided with a secondary exhaust gas nozzle for injecting oxygen-containing exhaust gas into the secondary exhaust gas chamber. Both the primary and secondary exhaust gas nozzles include at least two layers of exhaust gas nozzles.

[0014] The first-stage exhaust gas nozzle includes an A1 layer exhaust gas nozzle and an A2 layer exhaust gas nozzle. The A2 layer exhaust gas nozzle is located on the side of the A1 layer exhaust gas nozzle away from the burner housing. The outer wall of the first-stage exhaust gas chamber is provided with a first-stage annular part. The first-stage annular part and the outer wall of the first-stage exhaust gas chamber form a first-stage annular chamber. The A1 layer exhaust gas nozzle and the A2 layer exhaust gas nozzle are both circumferentially arranged on the first-stage exhaust gas chamber and connect the first-stage annular chamber and the internal space of the first-stage exhaust gas chamber. The first-stage annular part is provided with a first-stage exhaust gas inlet for introducing exhaust gas into the first-stage annular chamber.

[0015] The secondary exhaust gas nozzle includes a B1 layer exhaust gas nozzle and a B2 layer exhaust gas nozzle. The B2 layer exhaust gas nozzle is located on the side of the B1 layer exhaust gas nozzle away from the burner housing. A secondary annular section is provided on the outer wall of the secondary exhaust gas chamber. A secondary annular chamber is formed between the secondary annular section and the outer wall of the secondary exhaust gas chamber. Both the B1 layer exhaust gas nozzle and the B2 layer exhaust gas nozzle are circumferentially arranged on the secondary exhaust gas chamber and connect the secondary annular chamber and the internal space of the secondary exhaust gas chamber. The secondary annular section is provided with a secondary exhaust gas inlet for introducing exhaust gas into the secondary annular chamber.

[0016] Both the A1 layer exhaust nozzle and the A2 layer exhaust nozzle are arranged in a tangential swirling flow. The tangential angle of the A1 layer exhaust nozzle is approximately 30° to 45°, and the tangential angle of the A2 layer exhaust nozzle is approximately 25° to 40°.

[0017] Both the B1 and B2 exhaust nozzles are arranged in a tangential swirling pattern. The tangential angle of the B1 exhaust nozzle is approximately 20° to 35°, and the tangential angle of the B2 exhaust nozzle is approximately 15° to 30°.

[0018] The tangential swirling directions of the exhaust nozzles in layers A1, A2, B1, and B2 are consistent, and the geometric tangential circle diameters of their swirling directions are ΦA1 > ΦA2 > ΦB1 > ΦB2.

[0019] The inner diameter of the primary exhaust gas chamber is ΦA, the inner diameter of the secondary exhaust gas chamber is ΦB, and the inner diameter of the thermal oxidizer outlet is ΦK, where ΦA < ΦB < ΦK.

[0020] The oxygen-containing exhaust gas load is ≥300,000 Nm³ 3 At a rate of / h, a tertiary exhaust gas chamber is provided between the secondary exhaust gas chamber and the outlet of the thermal oxidizer. The tertiary exhaust gas chamber is equipped with a tertiary exhaust gas nozzle for injecting oxygen-containing exhaust gas into the secondary exhaust gas chamber. The tertiary exhaust gas nozzle includes at least 4 layers of exhaust gas nozzles.

[0021] In summary, this application includes at least the following beneficial technical effects:

[0022] (1) The present invention relates to a dual swirl burner and thermal oxidation device suitable for oxygen-containing exhaust gas. The burner adopts a dual swirl design structure. In the liquid fuel single combustion mode or gas-liquid mixed combustion mode, the combustion air and oxygen-containing exhaust gas are used for dual combustion. In the gas single combustion mode, oxygen-containing exhaust gas is used for single combustion. By optimizing the configuration of air and oxygen-containing exhaust gas, the system's operational flexibility and energy-saving effect are improved.

[0023] (2) The present invention relates to a dual swirl burner and thermal oxidation device suitable for oxygen-containing tail gas, which adopts gradient enhanced swirl combustion, and a large flow of oxygen-containing tail gas enters the furnace layer by layer in stages. In conjunction with the upstream dual swirl burner, the swirl intensity is effectively continued and expanded in the direction of flue gas flow in the furnace, realizing orderly mixing and step-by-step ignition of materials. In addition, the furnace structure is optimized by combining the gradient release law of material heat and flue gas volume change, and finally realizing the complete combustion of fuel gas, waste liquid and oxygen-containing tail gas in a limited space and at a set temperature. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of a dual swirl burner applicable to oxygen-containing exhaust gases, as described in this application.

[0025] Figure 2 This application is intended to illustrate a dual swirl burner with burner outlet 15 as a schematic diagram;

[0026] Figure 3 This is a schematic diagram of a thermal oxidation device applicable to oxygen-containing exhaust gases, as described in this application.

[0027] Figure 4 A schematic diagram showing the distribution of exhaust nozzles 222 in layer A1 and 223 in layer A2;

[0028] Figure 5 A schematic diagram showing the distribution of exhaust nozzle 232 in layer B1 and exhaust nozzle 223 in layer B2;

[0029] Figure 6 This is a schematic diagram of a thermal oxidation device suitable for ultra-high flow rates of oxygen-containing exhaust gas.

[0030] Explanation of reference numerals: 1. Burner shell; 2. Flame stabilizer; 3. Air cyclone separator; 4. Exhaust gas cyclone separator; 5. Center liquid nozzle; 6. Annular gas nozzle; 7. Center gas nozzle; 8. Surrounding liquid nozzle; 9. Refractory lining; 10. Air inlet; 11. Oxygen-containing exhaust gas inlet; 12. Air chamber; 13. Oxygen-containing exhaust gas chamber; 14. Mixing duct; 15. Burner outlet; 16. Inner shell; 17. Outer shell; 18. Baffle plate;

[0031] 210. Thermal oxidizer inlet; 220. Primary exhaust gas chamber; 221. Primary exhaust gas inlet; 222. A1 layer exhaust gas nozzle; 223. A2 layer exhaust gas nozzle; 230. Secondary exhaust gas chamber; 231. Secondary exhaust gas inlet; 232. B1 layer exhaust gas nozzle; 233. B2 layer exhaust gas nozzle; 240. Tertiary exhaust gas chamber; 241. Tertiary exhaust gas inlet; 242. C1 layer exhaust gas nozzle; 243. C2 layer exhaust gas nozzle; 244. C3 layer exhaust gas nozzle; 245. C4 layer exhaust gas nozzle; 250. Thermal oxidizer outlet. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments disclosed in the present invention will be described in further detail below with reference to the accompanying drawings.

[0033] This application discloses a dual-swirl burner and thermal oxidation device suitable for oxygen-containing exhaust gases, ideal for the environmentally friendly incineration of large-volume oxygen-containing exhaust gases, particularly applicable to the HCN industry and the maleic anhydride industry using the n-butane oxidation process, which employ new technologies. The dual-swirl burner and gradient-enhanced swirl combustion technology used in this invention have broad applicability in their technical principles. It should be understood that the specific embodiments described in this invention are only some examples of the invention, used solely to explain the invention and not constituting a limitation thereof. Where there is no conflict, the embodiments and technical features involved in this invention can be combined with each other.

[0034] The technical problem solved by this application is to achieve low-energy and complete decomposition of oxygen-containing exhaust gas, liquid fuel and gas fuel through the configuration of combustion organization and combustion air and oxygen-containing exhaust gas within a limited space.

[0035] For ease of explanation, a brief overview of the invention will be given first, such as... Figures 1-5 As shown, the oxygen-containing exhaust gas discharged from the upstream unit enters the boundary area, where it first undergoes condensation separation in a gas-liquid separator. The exhaust gas from the gas-liquid separator is then preheated before entering multiple pathways to the dual cyclone burner and the thermal oxidizer. The dual cyclone burner is installed on one side of the thermal oxidizer.

[0036] like Figures 1-2As shown, the dual-swirl burner includes: a burner shell 1, a flame stabilizer 2, an air swirler 3, a tail gas swirler 4, a central liquid gun 5, an annular gas gun 6, a central gas gun 7, a surrounding liquid gun 8, refractory material 9, an air inlet 10, an oxygen-containing tail gas inlet 11, an air chamber 12, an oxygen-containing tail gas chamber 13, a mixing duct 14, and a burner outlet 15. Combustion air and oxygen-containing tail gas pass through the air swirler 3 and the tail gas swirler 4 respectively, generating swirling airflows that enter the same mixing duct 14, achieving thorough mixing and combustion of liquid fuel and fuel gas.

[0037] The burner housing 1 includes a front cover, a rear cover, an inner housing 16, an outer housing 17, and a partition 18. The outer housing is fitted over the inner housing, and the front cover and rear cover are connected to the two ends of the outer housing and the inner housing, respectively. The partition connects the inner housing and the outer housing. The air cyclone 3 and the exhaust gas cyclone 4 both include through holes and inclined blades on the outer housing. The through holes are located between adjacent inclined blades. The air cyclone 3 and the exhaust gas cyclone 4 are located on both sides of the partition. The air inlet 10 and the oxygen-containing exhaust gas inlet 11 are both located on the outer housing. The central liquid gun 5, the annular gas gun 6, the central gas gun 7, and the peripheral liquid gun 8 are all connected to the front cover and inserted into the inner housing. The end of the inner housing away from the front housing extends out of the rear housing to form the burner outlet 15. The internal space of the inner housing forms a mixing duct 14. The two spaces located on both sides of the partition and between the inner housing and the outer housing are the air chamber 12 and the oxygen-containing exhaust gas chamber 13, respectively. Air inlet 10 and air chamber 12 are connected to mixing duct 14 and burner outlet 15; oxygen-containing exhaust gas inlet 11 and oxygen-containing exhaust gas chamber 13 are connected to mixing duct 14 and burner outlet 15; wherein mixing duct 14 and burner outlet 15 are common flow spaces for air and oxygen-containing exhaust gas, and mixing duct 14 and burner outlet 15 are coaxial.

[0038] The air cyclone 3 is located inside the burner housing 1 and connects the air inlet 10, the air cavity 12 and the mixing duct 14. It is used to generate a swirling effect in the combustion air so as to fully mix it with the waste liquid and fuel gas to be treated.

[0039] The exhaust gas cyclone 4 is located inside the burner housing 1 and connects the oxygen-containing exhaust gas inlet 11, the oxygen-containing exhaust gas chamber 13 and the mixing duct 14. It is used to generate a swirling effect in the oxygen-containing exhaust gas and fully mix it with the waste liquid and fuel gas to be treated.

[0040] The air cyclone 3 and the exhaust cyclone 4 rotate in the same direction, and their rotation angles are both adjustable.

[0041] The mixing duct 14 is arranged in a concentric circle structure with a central liquid gun 5, a central gas gun 7, a peripheral liquid gun 8, and an annular gas gun 6. The central liquid gun 5 and the central gas gun 7 are coaxially combined and arranged on the central axis of the dual swirl burner. The central gas gun 7 is located near the burner outlet 15 with a flame stabilizer 2. The peripheral liquid gun 8 is located outside the flame stabilizer 2 and consists of 2 to 6 liquid spray guns for injecting liquid fuel into the burner outlet 15. The annular gas gun 6 is located outside the peripheral liquid gun 8 and consists of 4 to 24 gas guns for injecting gaseous fuel into the burner outlet 15.

[0042] like Figure 3 As shown, the thermal oxidizer includes a thermal oxidizer inlet 210, a primary exhaust gas chamber 220, a secondary exhaust gas chamber 230, and a thermal oxidizer outlet 250.

[0043] like Figure 3 and Figure 4 As shown, the primary exhaust gas chamber 220 is equipped with two layers of exhaust gas nozzles, specifically including a connected primary exhaust gas inlet 221, an A1 layer exhaust gas nozzle 222, and an A2 layer exhaust gas nozzle 223. A primary annular portion is provided on the outer wall of the primary exhaust gas chamber 220, forming a primary annular chamber between the primary annular portion and the outer wall of the primary exhaust gas chamber 220. Both the A1 layer exhaust gas nozzle 222 and the A2 layer exhaust gas nozzle 223 are circumferentially arranged within the primary exhaust gas chamber 220. The first-stage annular chamber 20 is connected to the internal space of the first-stage exhaust gas chamber 220. The first-stage exhaust gas inlet 221 is located in the first-stage annular section for introducing exhaust gas into the first-stage annular chamber. Both the A1-layer exhaust gas nozzle 222 and the A2-layer exhaust gas nozzle 223 are arranged in a tangential swirling pattern. The tangential angle A1 of the A1-layer exhaust gas nozzle 222 is approximately 30°–45°, and the tangential angle A2 of the A2-layer exhaust gas nozzle 223 is approximately 25°–40°. The tangential angle of the A1-layer exhaust gas nozzle 222 is the angle between the ejection direction of the A1-layer exhaust gas nozzle 222 and the radial direction passing through the A1-layer exhaust gas nozzle 222.

[0044] like Figure 3 and Figure 5As shown, the secondary exhaust gas chamber 230 is equipped with two layers of exhaust gas nozzles, specifically including a connected secondary exhaust gas inlet 231, a B1 layer exhaust gas nozzle 232, and a B2 layer exhaust gas nozzle 233. A secondary annular portion is provided on the outer wall of the secondary exhaust gas chamber 230, forming a secondary annular chamber between the secondary annular portion and the outer wall of the secondary exhaust gas chamber 230. Both the B1 layer exhaust gas nozzle 232 and the B2 layer exhaust gas nozzle 233 are circumferentially arranged within the secondary exhaust gas chamber 230. The secondary annular chamber and the secondary exhaust gas chamber 230 are connected to the internal space of the secondary annular chamber. The secondary exhaust gas inlet 231 is located in the secondary annular part and is used to introduce exhaust gas into the secondary annular chamber. The exhaust gas nozzles 232 and 233 of the B1 layer are arranged in a tangential swirling flow. The tangential angle of the exhaust gas nozzle 232 of the B1 layer is approximately 20° to 35°, and the tangential angle of the exhaust gas nozzle 233 of the B2 layer is approximately 15° to 30°.

[0045] Among them, the tangential swirl directions of exhaust gas nozzles 222 (A1 layer), 223 (A2 layer), 232 (B1 layer), and 233 (B2 layer) are consistent, and the geometric tangential circle diameters of their swirl directions are ΦA1 > ΦA2 > ΦB1 > ΦB2. The high-speed kinetic energy jet ejected from the thermal oxidizer cooperates with the swirling flame of the upstream burner to ensure good coordination and mixing of the oxygen-containing exhaust gas and the burner outlet flame, ultimately achieving complete oxidation and decomposition of the oxygen-containing exhaust gas under conditions of liquid fuel combustion alone, gas combustion alone, or mixed combustion of liquid fuel and gas, resulting in compliant emissions.

[0046] The air and oxygen-containing exhaust gas produced by the dual-swirl burner have the same swirling direction as the oxygen-containing exhaust gas from the thermal oxidizer.

[0047] From the thermal oxidizer inlet 210 to the thermal oxidizer outlet 250, the diameter of the thermal oxidizer gradually increases as the exhaust gas is mixed in stages, where ΦA < ΦB < ΦK. ΦA is the inner diameter of the first-stage exhaust gas chamber 220, ΦB is the inner diameter of the second-stage exhaust gas chamber 230, and ΦK is the inner diameter of the next stage after the second-stage exhaust gas chamber 230. Specifically, when the second-stage exhaust gas chamber 230 is connected to the third-stage exhaust gas chamber 240, ΦK is the inner diameter of the third-stage exhaust gas chamber 240; when the second-stage exhaust gas chamber 230 is connected to the thermal oxidizer outlet 250, ΦK is the inner diameter of the thermal oxidizer outlet 250.

[0048] like Figure 6 As shown, this thermal oxidizer is suitable for oxygen-containing exhaust gas loads ≤ 300,000 Nm³. 3 / h; when the oxygen-containing exhaust gas load is ≥300,000 Nm³ 3 / h, furthermore, the thermal oxidizer needs to be equipped with a three-stage exhaust gas chamber 240, such as Figure 6As shown, the three-stage exhaust gas chamber 240 contains four layers of exhaust gas nozzles, specifically including a connected three-stage exhaust gas inlet 241, a C1 layer exhaust gas nozzle 242, a C2 layer exhaust gas nozzle 243, a C3 layer exhaust gas nozzle 244, and a C4 layer exhaust gas nozzle 245.

[0049] The exhaust nozzles 222 (A1 layer), 223 (A2 layer), 232 (B1 layer), 233 (B2 layer), 242 (C1 layer), 243 (C2 layer), 244 (C3 layer), and 245 (C4 layer) eject high-speed oxygen-containing exhaust gas jets with a flow velocity range of 40–70 m / s, providing kinetic energy and swirling intensity for the mixed combustion of liquid fuel, fuel gas, oxygen-containing exhaust gas, and combustion air.

[0050] Furthermore, the first-stage exhaust gas chamber 220 may contain three or more exhaust gas nozzles; furthermore, the second-stage exhaust gas chamber 230 may contain three or more exhaust gas nozzles; furthermore, the third-stage exhaust gas chamber 240 may contain five or more exhaust gas nozzles.

[0051] The exhaust nozzles 222 (layer A1), 223 (layer A2), 232 (layer B1), 233 (layer B2), 242 (layer C1), 243 (layer C2), 244 (layer C3), and 245 (layer C4) can be made of heat-resistant steel or heat-resistant ceramic.

[0052] The dual-swirling burner achieves a powerful swirling flow of air and oxygen-containing exhaust gas through two types of swirlers. Both air and oxygen-containing exhaust gas can provide oxygen for material combustion, satisfying single-fuel or mixed-fuel combustion conditions for both gas and liquid fuels. In particular, when using liquid fuel as the combustion heat source, dual combustion is aided by air and oxygen-containing exhaust gas; when using gas as the combustion heat source, oxygen-containing exhaust gas is used alone for combustion. By optimizing the combustion organization, the amount of air mixed in is minimized, achieving energy-saving combustion and providing a heat source for the combustion and decomposition of the large flow of oxygen-containing exhaust gas in the thermal oxidizer. The thermal oxidizer adopts a two-stage or three-stage exhaust gas swirling mixing structure, which works in conjunction with the swirling flame of the upstream burner to ensure good coordination and mixing of oxygen-containing exhaust gas and burner flame. Ultimately, it achieves complete oxidation and decomposition of oxygen-containing exhaust gas under single-fuel combustion, single-fuel combustion, or mixed-fuel combustion conditions for liquid fuel or gas, ensuring that the flue gas meets emission standards.

[0053] Example 1

[0054] In this embodiment, the exhaust gas from the gas-liquid separator is HCN exhaust gas. The components and state parameters of the HCN exhaust gas to be treated are shown in Table 1. This oxygen-containing exhaust gas has a low calorific value. It is combusted using waste liquid and natural gas. The dual-cyclone burner can meet three operating conditions: combustion with waste liquid alone, combustion with natural gas alone, or gas-liquid co-firing. Since the gas-liquid co-firing condition is similar to that in Example 2, this example only describes the natural gas-only combustion condition. Figures 1-5As shown, the present invention provides a dual swirl burner and thermal oxidation device suitable for oxygen-containing exhaust gas, which uses natural gas to provide heat to complete the thermal decomposition of oxygen-containing exhaust gas.

[0055] Table 1 HCN Exhaust Gas Components and State Parameters

[0056]

[0057] The dual swirl burner employs staged combustion, producing approximately 2700 Nm³ / h. 3 The gas supply is divided into two routes to the burner, with approximately 300 Nm³ / h of gas being supplied. 3 / h is supplied to the central gas gun 7, approximately 2400 Nm 3 The annular gas gun 6 is introduced at / h, which, together with the flame stabilizer 2, forms a multi-layered hollow flame, thereby reducing the overall flame temperature and achieving low-NOx combustion.

[0058] The dual-swirl burner employs low-oxygen combustion, utilizing only oxygen-containing exhaust gas to supply oxygen to the natural gas. The oxygen-containing exhaust gas enters the oxygen-containing exhaust gas chamber 13 through the oxygen-containing exhaust gas inlet 11, and then flows through the exhaust gas swirl generator 4, generating a strong swirl before entering the mixing duct 14. This achieves thorough mixing of the natural gas and the oxygen-containing exhaust gas, resulting in low-NOx combustion. By completely utilizing the oxygen-containing exhaust gas for combustion, air introduction is stopped, reducing fuel consumption and achieving energy-efficient combustion. The burner employs an adaptive control method, with the control loop automatically proportionally controlling the oxygen-containing exhaust gas supply to the natural gas flow rate.

[0059] Most of the oxygen-containing exhaust gas enters the primary exhaust gas chamber 220 and the secondary exhaust gas chamber 230 of the thermal oxidizer in two stages. The ratio of oxygen-containing exhaust gas entering the primary exhaust gas chamber 220 and the secondary exhaust gas chamber 230 is approximately 4:6. The primary exhaust gas chamber 220 contains two layers of nozzles: A1 layer exhaust gas nozzle 222 and A2 layer exhaust gas nozzle 223. The secondary exhaust gas chamber 230 contains two layers of nozzles: B1 layer exhaust gas nozzle 232 and B2 layer exhaust gas nozzle 233. Exhaust nozzles 222 (layer A1), 223 (layer A2), 232 (layer B1), and 233 (layer B2) are all arranged in a tangential swirling pattern, with the swirling direction consistent. The tangential angle of exhaust nozzle 222 is A1 = 40°, that of exhaust nozzle 223 is A2 = 30°, that of exhaust nozzle 232 is B1 = 20°, and that of exhaust nozzle 233 is B2 = 10°. The exhaust gas jet velocity from the four exhaust nozzle layers is approximately 40 m / s, and the diameter of their geometric tangential circles decreases progressively. Figures 4-5 As shown, ΦA1>ΦA2>ΦB1>ΦB2.

[0060] The outlet temperature of the thermal oxidizer is approximately 900℃. This invention employs gradient-enhanced swirl combustion, with most of the oxygen-containing exhaust gas entering the thermal oxidizer in two stages, layer by layer. Combined with the upstream dual swirl burner, this achieves orderly mixing and step-by-step ignition of the materials, ultimately ensuring complete combustion of natural gas and oxygen-containing exhaust gas within a limited space and at a set temperature.

[0061]

[0062] Example 2

[0063] In this embodiment, the exhaust gas from the gas-liquid separator is maleic anhydride exhaust gas. The components and state parameters of the maleic anhydride exhaust gas to be treated are shown in Table 3. This oxygen-containing exhaust gas has a low calorific value. It is combusted using waste liquid and natural gas. The dual-cyclone burner can meet three operating conditions: combustion assisted by waste liquid alone, combustion assisted by natural gas alone, or gas-liquid co-firing combustion. This example only describes the gas-liquid co-firing condition. Figure 1 , Figure 2 and Figure 6 As shown, the present invention provides a dual swirl burner and thermal oxidation device suitable for oxygen-containing exhaust gases.

[0064] Table 2. Components and State Parameters of Maleic Anhydride Tail Gas

[0065]

[0066] The dual-swirling burner employs multi-flame combustion. Approximately 3000 kg / h of high-calorific-value waste liquid is supplied to the burner via two routes: approximately 0 kg / h is supplied to the central liquid gun 5, and approximately 0 kg / h is supplied to four peripheral liquid guns 8; simultaneously, approximately 0 Nm 3 Natural gas is supplied to the annular gas gun 6 of the burner at a rate of / h. The atomized liquid and natural gas injected by the central liquid gun 5, the surrounding liquid guns 8 and the multiple annular gas guns 6 form numerous small flames, which, together with the flame stabilizer 2, form a uniform flame in the space of the burner outlet 15, thereby reducing the overall flame temperature and achieving low-NOx combustion.

[0067] The dual-swirling burner employs low-oxygen combustion, simultaneously using combustion air and maleic anhydride tail gas to provide oxygen for the combustion of waste liquid and natural gas. Combustion air enters the air chamber 12 through air inlet 10, then flows through air swirler 3, generating a strong swirling flow before entering the mixing duct 14. Oxygen-containing tail gas enters the oxygen-containing tail gas chamber 13 through oxygen-containing tail gas inlet 11, then flows through tail gas swirler 4. The combustion air and maleic anhydride tail gas form a dual-swirling airflow in the same mixing duct 14, mutually entraining and reinforcing each other, achieving thorough mixing of waste liquid, natural gas, air, and maleic anhydride tail gas, thus achieving low-NOx combustion through low-oxygen combustion. Simultaneously, the low-oxygen combustion technology, using partially oxygenated maleic anhydride tail gas for combustion assistance, reduces fuel consumption by minimizing air intake, achieving energy-efficient combustion. The burner employs adaptive control; the control loop automatically proportionally controls the oxygen-containing tail gas supply and natural gas flow rate, and the control loop also automatically proportionally controls the waste liquid supply and air flow rate.

[0068] like Figure 6 As shown, most of the oxygen-containing exhaust gas enters the primary exhaust gas chamber 220, secondary exhaust gas chamber 230, and tertiary exhaust gas chamber 240 of the thermal oxidizer in three stages. The ratio of maleic anhydride exhaust gas entering the primary exhaust gas chamber 220, secondary exhaust gas chamber 230, and tertiary exhaust gas chamber 240 is approximately 2:3:5. The primary exhaust gas chamber 220 contains two layers of nozzles: A1 layer exhaust gas nozzle 222 and A2 layer exhaust gas nozzle 223. The secondary exhaust gas chamber 230 contains two layers of nozzles: B1 layer exhaust gas nozzle 232 and B2 layer exhaust gas nozzle 233. The tertiary exhaust gas chamber 240 contains four layers of nozzles: C1 layer exhaust gas nozzle 242, C2 layer exhaust gas nozzle 243, C3 layer exhaust gas nozzle 244, and C4 layer exhaust gas nozzle 245. Exhaust nozzles 222 (layer A1), 223 (layer A2), 232 (layer B1), and 233 (layer B2) are all arranged in a tangential swirling pattern, with the swirling direction consistent. The tangential angle of exhaust nozzle 222 in layer A1 is A1 = 35°, that of exhaust nozzle 223 in layer A2 is A2 = 30°, that of exhaust nozzle 232 in layer B1 is B1 = 25°, and that of exhaust nozzle 233 in layer B2 is B2 = 20°. The geometric tangential circle diameters of the first four exhaust nozzle layers decrease progressively, as shown below. Figures 4-5 As shown, ΦA1>ΦA2>ΦB1>ΦB2. The C1 layer exhaust nozzle 242, C2 layer exhaust nozzle 243 and C3 layer exhaust nozzle 244 included in the three-stage exhaust gas chamber 240 adopt tangential swirling flow and the swirling flow direction is consistent, while the C4 layer exhaust nozzle 245 adopts centripetal counterflow.

[0069] The outlet temperature of the thermal oxidizer is approximately 800℃. This invention employs gradient-enhanced swirl combustion, with most of the maleic anhydride tail gas entering the thermal oxidizer in three stages, layer by layer. Combined with the upstream dual swirl burner, this achieves orderly mixing and step-by-step ignition of materials, ultimately ensuring complete combustion of waste liquid, natural gas, maleic anhydride tail gas, and combustion air within a limited space and at a set temperature.

[0070]

[0071] The contents not described in detail in this application specification are common knowledge to those skilled in the art.

[0072] The present application has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present application. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and implementation methods of the present application without departing from the spirit and scope of the present application, and all such modifications and improvements fall within the scope of the present application. The scope of protection of the present application is determined by the appended claims.

Claims

1. A dual-swirl burner suitable for oxygen-containing exhaust gases, characterized in that: Includes a burner housing (1), an air cyclone separator (3), a tail gas cyclone separator (4), a liquid gun, and a gas gun; The burner housing (1) includes a front cover, a rear cover, an inner housing (16), an outer housing (17), and a partition (18). The outer housing (17) is fitted over the inner housing (16). The front cover and the rear cover are connected to the two ends of the outer housing (17) and the inner housing (16), respectively. The partition (18) connects the inner housing (16) and the outer housing (17) and divides the space between the inner housing (16) and the outer housing (17) into an air chamber (12) and an oxygen-containing exhaust gas chamber (13). The outer housing (17) is provided with an air inlet (10) and an oxygen-containing exhaust gas inlet (11). The inlet (10) is connected to the air chamber (12), and the oxygen-containing exhaust gas inlet (11) is connected to the oxygen-containing exhaust gas chamber (13); a mixing duct (14) is formed inside the inner shell (16), and the end of the inner shell (16) away from the front shell passes through the rear shell to form the burner outlet (15); the air cyclone (3) and the exhaust gas cyclone (4) are installed in the inner shell (16) and are located on both sides of the partition (18), respectively. The air cyclone (3) connects the air chamber (12) and the mixing duct (14), and the exhaust gas cyclone (4) connects the oxygen-containing exhaust gas chamber (13) and the mixing duct (14); The liquid gun and gas gun are connected to the front cover and extend from inside the inner housing (16) to the burner outlet (15).

2. The dual-swirl burner suitable for oxygen-containing exhaust gas according to claim 1, characterized in that: The air cyclone (3) and the exhaust cyclone (4) make the airflow rotate in the same direction; both the air cyclone (3) and the exhaust cyclone (4) include through holes and inclined blades provided on the inner shell (16), with the through holes located between adjacent inclined blades; the airflow passes between the inclined blades and then enters the mixing duct (14) through the through holes to form a rotating airflow.

3. A dual-swirl burner suitable for oxygen-containing exhaust gas according to claim 1, characterized in that: The liquid gun and gas gun include a central liquid gun (5), an annular gas gun (6), a central gas gun (7), and a surrounding liquid gun (8). The central liquid gun (5) and the central gas gun (7) are coaxially combined. The central gas gun (7) is sleeved outside the central liquid gun (5). The central gas gun (7) and the surrounding liquid gun (8) are arranged in a concentric circle structure outside the central gas gun (7). The central liquid gun (5) and the surrounding liquid gun (8) are used to inject liquid fuel into the burner outlet (15), and the central gas gun (7) and the annular gas gun (6) are used to inject gaseous fuel into the burner outlet (15).

4. A dual-swirl burner suitable for oxygen-containing exhaust gas according to claim 3, characterized in that: The central gas gun (7) is fitted with a flame stabilizer (2) at the end near the burner outlet (15), the surrounding liquid gun (8) is arranged outside the flame stabilizer (2), and the annular gas gun (6) is arranged outside the surrounding liquid gun (8).

5. A dual-swirl burner suitable for oxygen-containing exhaust gas according to claim 3, characterized in that: When the liquid fuel provides the heat source for combustion, air is introduced into the air inlet (10) and oxygen-containing exhaust gas is introduced into the oxygen-containing exhaust gas inlet (11), and dual combustion is achieved using air and oxygen-containing exhaust gas; when the gas is used to provide the heat source for combustion, oxygen-containing exhaust gas is introduced into the oxygen-containing exhaust gas inlet (11) and the air inlet (10) is closed, and oxygen-containing exhaust gas is used to assist combustion alone.

6. A thermal oxidation device suitable for oxygen-containing exhaust gas, characterized in that: The device includes an oxidizer inlet (210), a primary tail gas chamber (220), a secondary tail gas chamber (230), a thermal oxidizer outlet (250), and a dual swirl burner suitable for oxygen-containing tail gas as described in any one of claims 1-5. The burner outlet (15) of the burner shell (1) is connected to the oxidizer inlet (210). The oxidizer inlet (210), the primary tail gas chamber (220), the secondary tail gas chamber (230), and the thermal oxidizer outlet (250) are connected in sequence. The primary tail gas chamber (220) is provided with a primary tail gas nozzle for injecting oxygen-containing tail gas into the primary tail gas chamber (220). The secondary tail gas chamber (230) is provided with a secondary tail gas nozzle for injecting oxygen-containing tail gas into the secondary tail gas chamber (230). Both the primary tail gas nozzle and the secondary tail gas nozzle include at least two layers of tail gas nozzles.

7. A thermal oxidation device suitable for oxygen-containing exhaust gas according to claim 6, characterized in that: The first-stage exhaust gas nozzle includes an A1 layer exhaust gas nozzle (222) and an A2 layer exhaust gas nozzle (223). The A2 layer exhaust gas nozzle (223) is located on the side of the A1 layer exhaust gas nozzle (222) away from the burner housing (1). The outer wall of the first-stage exhaust gas chamber (220) is provided with a first-stage annular part. The first-stage annular part and the outer wall of the first-stage exhaust gas chamber (220) form a first-stage annular chamber. The A1 layer exhaust gas nozzle (222) and the A2 layer exhaust gas nozzle (223) are both circumferentially arranged on the first-stage exhaust gas chamber (220) and connect the first-stage annular chamber and the internal space of the first-stage exhaust gas chamber (220). The first-stage annular part is provided with a first-stage exhaust gas inlet (221) for introducing exhaust gas into the first-stage annular chamber. The secondary exhaust nozzle includes a B1 layer exhaust nozzle (232) and a B2 layer exhaust nozzle (233). The B2 layer exhaust nozzle (233) is located on the side of the B1 layer exhaust nozzle (232) away from the burner housing (1). The outer wall of the secondary exhaust chamber (230) is provided with a secondary annular part. The secondary annular part and the outer wall of the secondary exhaust chamber (230) form a secondary annular chamber. The B1 layer exhaust nozzle (232) and the B2 layer exhaust nozzle (233) are both circumferentially arranged on the secondary exhaust chamber (230) and connect the secondary annular chamber and the internal space of the secondary exhaust chamber (230). The secondary annular part is provided with a secondary exhaust inlet (231) for introducing exhaust gas into the secondary annular chamber.

8. A thermal oxidation device suitable for oxygen-containing exhaust gas according to claim 7, characterized in that: The exhaust nozzles (222) in layer A1 and layer A2 are both arranged in a tangential swirling pattern. The tangential angle of exhaust nozzle (222) in layer A1 is approximately 30°~45°, and the tangential angle of exhaust nozzle (223) in layer A2 is approximately 25°~40°. Both the exhaust nozzles (232) in layer B1 and (233) in layer B2 are arranged in a tangential swirling pattern. The tangential angle of exhaust nozzle (232) in layer B1 is approximately 20°~35°, and the tangential angle of exhaust nozzle (233) in layer B2 is approximately 15°~30°.

9. A thermal oxidation device for oxygen-containing exhaust gas according to claim 7, characterized in that: The tangential swirling directions of the exhaust nozzles (222) in layer A1, (223) in layer A2, (232) in layer B1 and (233) in layer B2 are consistent, and the geometric tangential circle diameters of their swirling directions are ΦA1>ΦA2>ΦB1>ΦB2. The inner diameter of the first-stage exhaust gas chamber (220) is ΦA, the inner diameter of the second-stage exhaust gas chamber (230) is ΦB, and the inner diameter of the thermal oxidizer outlet (250) is ΦK, where ΦA < ΦB < ΦK.

10. A thermal oxidation device for oxygen-containing exhaust gas according to claim 6, characterized in that: When the oxygen-containing tail gas load is ≥300,000 Nm³ / h, a tertiary tail gas chamber (240) is set between the secondary tail gas chamber (230) and the thermal oxidizer outlet (250). The tertiary tail gas chamber (240) is equipped with a tertiary tail gas nozzle for injecting oxygen-containing tail gas into the secondary tail gas chamber (230). The tertiary tail gas nozzle includes at least 4 layers of tail gas nozzles.

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