A garbage incineration device with mixed combustion of ammonia and its control method

Abstract

The present invention discloses a waste incineration device for co-firing ammonia and a control method thereof. The device comprises an incinerator body and a secondary combustion chamber, wherein the lower end of the secondary combustion chamber is connected to the flue gas outlet at the upper end of the incinerator body. A grate is provided in the incinerator body. A first primary air duct, a second primary air duct, a third primary air duct, and a fourth primary air duct are sequentially provided at the bottom of the incinerator body below the grate. A primary ammonia pipeline is provided on at least one of the first, second, third, and fourth primary air ducts. A secondary air duct is provided at the lower end of the secondary combustion chamber, and a secondary ammonia pipeline is provided on the secondary air duct. The secondary combustion chamber is provided with a plurality of ammonia nozzles distributed in a vertical direction. The present invention couples the utilization of ammonia as a fuel energy source into the waste incineration process, provides a new technical route for the clean utilization of ammonia, and improves the combustion efficiency of ammonia in the waste incineration process.

Description

Technical Field

[0001] The present invention relates to a garbage incineration device and a control method thereof, in particular to a garbage incineration device for co-firing ammonia and a control method thereof, belonging to the technical field of garbage incineration. Background Art

[0002] The products of ammonia combustion are water and nitrogen, which does not cause carbon emissions. It is another zero-carbon energy source after hydrogen. Compared with hydrogen, ammonia has the advantages of easy transportation and storage, high energy density, and high safety. As a fuel, ammonia has the characteristics of difficult ignition, low laminar flame speed, and poor stability, which makes the ignition and combustion of pure ammonia difficult, which is also the main problem that needs to be solved in ammonia energy utilization. The combustion of ammonia alone requires an oxygen-rich or even pure oxygen environment. Therefore, the current main direction of ammonia combustion technology is the co-combustion of ammonia with other fuels, such as co-combustion of ammonia with pulverized coal, co-combustion of ammonia with short-chain hydrocarbons, and co-combustion of ammonia with hydrogen. Research has shown that even under co-combustion conditions, to achieve a high degree of ammonia reaction completion, there are still relatively strict requirements on the physical properties, purity, blending ratio, and combustion conditions of the co-combustion objects.

[0003] Incineration of municipal solid waste for power generation is a clean way to recycle waste resources. With the continuous improvement of waste sorting and waste recycling in my country, the amount of non-recyclable municipal solid waste entering incinerators is expected to decline. At that time, existing incinerators may face the problem of "not being able to meet the demand", requiring supplemental energy to ensure stable operation and power generation. Using ammonia as a supplemental fuel, combining waste incineration with ammonia energy, can leverage the respective advantages of waste incineration power generation and ammonia energy, providing a new energy model that is both low-carbon, environmentally friendly, and cost-effective.

[0004] In addition, ammonia is a commonly used denitrification raw material in traditional waste incineration power generation. In SNCR and SCR reaction devices, ammonia and NO x Reaction, removal of NO in flue gas x, a method commonly used in waste incineration power plants. Therefore, in the waste incineration power generation process using co-combustion ammonia, a small amount of ammonia residue from the combustion process can be allowed to be used as a denitrification raw material, avoiding the subsequent addition of additional ammonia. From this perspective, waste incineration using co-combustion ammonia has a higher tolerance for ammonia residue. However, because the combustion process in waste incineration power generation is far more complex than that of pulverized coal combustion or gas combustion, it includes not only the drying, pyrolysis, gasification, and combustion of solid waste within the grate, but also the gas-phase combustion of combustible flue gas in the secondary combustion chamber. In particular, the physical property imbalances at different locations in the grate and the uneven mixing of the gas phase in the secondary combustion chamber exacerbate the complexity and instability of the waste incineration process. Therefore, the co-combustion process of ammonia and domestic waste is inevitably more complex. The method, location, and proportion of ammonia addition have a significant impact on the co-combustion effect. Existing ammonia co-combustion technology is difficult to directly apply to waste incineration power generation scenarios, and there is currently no dedicated waste incineration power generation combined with ammonia co-combustion technology. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a waste incineration device for co-combustion of ammonia and a control method thereof, which solves the problem that the existing technology cannot couple ammonia energy utilization with waste incineration power generation because ammonia is not easy to burn.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0007] A garbage incineration device for co-firing ammonia comprises an incinerator body and a secondary combustion chamber, the lower end of the secondary combustion chamber is connected to the flue gas outlet at the upper end of the incinerator body, a grate is arranged in the incinerator body, a first primary air duct, a second primary air duct, a third primary air duct and a fourth primary air duct are arranged in sequence at the bottom of the incinerator body below the grate, at least one of the first primary air duct, the second primary air duct, the third primary air duct and the fourth primary air duct is provided with a primary ammonia pipeline, a secondary air duct is provided at the lower end of the secondary combustion chamber, a secondary ammonia pipeline is provided on the secondary air duct, and the secondary combustion chamber is provided with multiple ammonia nozzles distributed in a vertical direction.

[0008] Furthermore, the incinerator body is divided into a drying section, a pyrolysis gasification section, a combustion section and a burnout section along the feed port to the other side, and the first primary air duct, the second primary air duct, the third primary air duct and the fourth primary air duct are respectively arranged in the drying section, the pyrolysis gasification section, the combustion section and the burnout section.

[0009] Furthermore, the ammonia nozzles include a first ammonia nozzle, a second ammonia nozzle and a third ammonia nozzle, and the first ammonia nozzle, the second ammonia nozzle and the third ammonia nozzle are arranged at equal intervals on the side of the secondary combustion chamber from bottom to top.

[0010] Furthermore, the primary ammonia pipeline, the secondary ammonia pipeline and the plurality of ammonia nozzles are all connected to an ammonia storage device and are supplied with ammonia by the ammonia storage device.

[0011] Furthermore, a first probe group for detecting the flue gas temperature and the ammonia and oxygen concentrations in the flue gas is provided on the upper side of the combustion section, a second probe group for detecting the ammonia, nitrogen oxides and oxygen concentrations in the flue gas is provided between the secondary air duct of the secondary combustion chamber and the ammonia nozzle, and a third probe group for detecting the ammonia, nitrogen oxides and oxygen concentrations in the flue gas is provided at the outlet of the secondary combustion chamber.

[0012] Furthermore, flow regulating valves are provided on the first primary air duct, the second primary air duct, the third primary air duct, the fourth primary air duct, the primary ammonia duct, the secondary air duct, the secondary ammonia duct and the multiple ammonia nozzles, and all the flow regulating valves are connected to the ammonia automatic regulating device and controlled by the ammonia automatic regulating device. The first probe group, the second probe group and the third probe group are connected to the ammonia automatic regulating device and upload the collected parameters to the ammonia automatic regulating device.

[0013] Furthermore, the air in the first primary air duct, the second primary air duct, the third primary air duct, the fourth primary air duct and the secondary air duct is normal temperature air or preheated air of 100-250°C; the air in the first primary air duct, the second primary air duct, the third primary air duct, the fourth primary air duct and the secondary air duct is ordinary air or oxygen-enriched air.

[0014] A control method for a waste incineration device with co-combustion of ammonia comprises the following steps:

[0015] S1. Close all ammonia inlets and start the ammonia-co-fired waste incinerator according to the startup process of a common grate-type waste incinerator until the waste in the ammonia-co-fired waste incinerator is stably burned;

[0016] S2. Open the ammonia nozzles in the secondary combustion chamber layer by layer from top to bottom, and adjust the ammonia injection rate of the ammonia nozzles through the ammonia automatic regulating device until the emission of ammonia and nitrogen oxides in the combustion flue gas meets the standards;

[0017] S3. Open the inlet of the secondary ammonia pipeline and gradually increase the secondary ammonia flow rate to the set value. At the same time, increase the secondary air flow rate to maintain the residual oxygen concentration in the combustion flue gas unchanged. During this period, adjust the ammonia supply of the ammonia nozzles on each layer to ensure that the emission of ammonia and nitrogen oxides in the combustion flue gas continues to meet the standards;

[0018] S4. After the combustion stabilizes, open the primary ammonia pipeline inlet and gradually increase the primary ammonia flow rate to the set value. At the same time, increase the primary air flow rate to maintain the residual oxygen concentration in the combustion flue gas unchanged. During this period, continue to adjust the ammonia supply of each layer of ammonia nozzles to ensure that the emissions of ammonia and nitrogen oxides in the combustion flue gas meet the standards.

[0019] S5. During operation, the combustion efficiency of the ammonia co-combustion process is optimized through flow control, ensuring complete combustion while maintaining the emission standards of ammonia and nitrogen oxides;

[0020] S6. When the device is ready to shut down, first gradually reduce the primary ammonia flow rate until it is completely shut off, then gradually reduce the secondary ammonia flow rate until it is completely shut off. During this period, the flow rate of the ammonia nozzle is adjusted to ensure that the emission of ammonia and nitrogen oxides meets the standards. After the primary ammonia and secondary ammonia are completely shut off, close each ammonia nozzle layer by layer from bottom to top;

[0021] S7 Complete the shutdown of the co-burning ammonia waste incinerator according to the shutdown process of the ordinary grate-type waste incinerator, until the co-burning ammonia waste incinerator completely stops running and cools down.

[0022] Furthermore, in step S3, the molar ratio of the total flow rate of secondary ammonia to the secondary air flow rate does not exceed 8%, and the molar ratio of the primary ammonia to the primary air flow rate does not exceed 5%.

[0023] Furthermore, the step S5 is specifically as follows:

[0024] 5.1. Read the flue gas temperature T1 and the ammonia concentration C in the flue gas in the first probe group 氨1 , oxygen concentration C 氧1 , take the time scale T S1 The time average value within the range is compared with the flue gas temperature control value A, the ammonia concentration control value B and the oxygen concentration control value C respectively;

[0025] When the flue gas temperature T1 is lower than the flue gas temperature control value A, the ammonia supply is reduced until the supply is completely stopped;

[0026] When the flue gas temperature T1 is greater than the flue gas temperature control value A, and the ammonia concentration C in the flue gas 氨1 When the ammonia concentration is greater than the control value B, reduce the ammonia supply to ammonia concentration C. 氨1 Less than the ammonia concentration control value B;

[0027] When the flue gas temperature T1 is greater than the flue gas temperature control value A, the ammonia concentration C in the flue gas 氨1 Less than the ammonia concentration control value B, oxygen concentration C 氧1 When the oxygen concentration is greater than the control value C, increase the ammonia supply to ammonia concentration C 氨1 Reach ammonia control value B or oxygen concentration C 氧1 Dropped to less than the oxygen concentration control value C;

[0028] When the flue gas temperature T1 is greater than the flue gas temperature control value A, the ammonia concentration C in the flue gas 氨1 Less than the ammonia concentration control value B, oxygen concentration C 氧1 When the oxygen concentration is less than the control value C, the ammonia supply is maintained unchanged;

[0029] 5.2. Read the oxygen concentration C in the flue gas detected by the second probe group 氧2 , ammonia concentration C 氨2 and nitrogen oxide concentration C 氮氧化物 , take the time scale T S2 The time average value within 30 min was compared with the oxygen concentration control value D, the ammonia concentration control value E and the nitrogen oxide concentration control value F respectively;

[0030] When the oxygen concentration C 氧2 When the oxygen concentration is greater than the control value D, keep the secondary ammonia supply unchanged and reduce the secondary air supply to the oxygen concentration C 氧2 Until the value is less than the oxygen concentration control value D;

[0031] When the oxygen concentration C 氧2 Less than the oxygen concentration control value D, the ammonia concentration in the flue gas C 氨2 When the ammonia concentration is greater than the control value E, keep the secondary air supply unchanged and reduce the secondary ammonia supply until the ammonia concentration C 氨2 Less than the ammonia concentration control value E or oxygen concentration C 氧2 Greater than the oxygen concentration control value D;

[0032] When the oxygen concentration C 氧2 Less than the oxygen concentration control value D, the ammonia concentration in the flue gas C 氨2 Less than the ammonia concentration control value E, nitrogen oxide concentration C 氮氧化物 When the concentration of nitrogen oxides is greater than the control value F, keep the secondary air supply unchanged and increase the supply of secondary ammonia until the concentration of nitrogen oxides C 氮氧化物 Less than the nitrogen oxide concentration control value F or ammonia concentration C 氨2 Greater than the ammonia concentration control value E;

[0033] When the oxygen concentration C 氧2 Less than the oxygen concentration control value D, the ammonia concentration in the flue gas C 氨2 Less than the ammonia concentration control value E, nitrogen oxide concentration C 氮氧化物 When the concentration is less than the nitrogen oxide control value F, the supply of secondary air and secondary ammonia is maintained unchanged.

[0034] Compared with the prior art, the present invention has the following advantages and effects:

[0035] 1. The present invention couples ammonia as a fuel energy source to the waste incineration process, providing a new technical route for the clean utilization of ammonia;

[0036] 2. In the present invention, ammonia and primary air are fully mixed before entering the grate, which facilitates the full reaction of ammonia and air in the process of passing through the high-temperature material layer, thereby improving the combustion efficiency of ammonia;

[0037] 3. The secondary ammonia inlet provided near the secondary air inlet of the present invention can supplement the ammonia deficiency in the primary air and adjust the supply of secondary ammonia according to the ammonia combustion situation reflected by the flue gas composition to ensure combustion efficiency;

[0038] 4. In the present invention, the residual ammonia that is not fully burned reacts with the nitrogen oxides generated by combustion under high temperature conditions to reduce the nitrogen oxide content in the flue gas. The multi-layer ammonia nozzle arrangement can flexibly adjust the amount and location of ammonia addition to ensure the complete removal of nitrogen oxides without the need for additional nitrogen oxide removal devices.

[0039] 5. The present invention automatically adjusts and optimizes the mixed combustion process of ammonia and domestic waste, reducing human intervention in the process and the risks caused by operator inexperience or operational errors;

[0040] 6. The present invention can be implemented by utilizing existing grate-type waste incinerators through appropriate technical transformation, and is very suitable for technical upgrading of existing grate-type waste incinerators. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a schematic diagram of a waste incineration device for co-firing ammonia according to the present invention. DETAILED DESCRIPTION

[0042] In order to elaborate on the technical solutions adopted by the present invention to achieve the predetermined technical purpose, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments, and the technical means or technical features in the embodiments of the present invention can be replaced without creative work. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0043] like Figure 1As shown, the waste incineration device for co-combustion of ammonia of the present invention comprises an incinerator body 1 and a secondary combustion chamber 2. The incinerator body 1 adopts an inclined structural design. A feed port is provided on the upper side of the left end of the incinerator body 1, a slag discharge port is provided on the lower side of the right end of the incinerator body 1, and a flue gas outlet is provided on the upper side of the incinerator body 1. The secondary combustion chamber 2 is arranged in a vertical direction, and the flue gas inlet at the lower end of the secondary combustion chamber 2 is connected to the flue gas outlet at the upper end of the incinerator body 1 to form a complete waste incineration device. A grate 3 is provided in the incinerator body 1. The bottom surface of the incinerator body 1 is an inclined surface. The grate 3 is provided on the lower side of the furnace of the incinerator body 1 parallel to the bottom surface of the incinerator body 1. The first primary air duct 4, the second primary air duct 5, the third primary air duct 6 and the fourth primary air duct 7 are sequentially arranged at the bottom of the incinerator body 1 below the grate 3. One ends of the first primary air duct 4, the second primary air duct 5, the third primary air duct 6 and the fourth primary air duct 7 are connected to the bottom of the incinerator body 1 through an inverted cone-shaped air distribution cylinder, and the other ends of the first primary air duct 4, the second primary air duct 5, the third primary air duct 6 and the fourth primary air duct 7 are connected to the primary air main 8.

[0044] A primary ammonia pipeline 9 is provided on at least one of the first primary air pipeline 4, the second primary air pipeline 5, the third primary air pipeline 6 and the fourth primary air pipeline 7. Of course, the primary ammonia pipeline 9 can also be provided on the primary air main pipeline 8. In this embodiment, preferably, the primary ammonia pipeline 9 is provided on the third primary air pipeline 6. The combustion section is the main combustion area of ​​the incinerator body 1. By supplying ammonia to this area, the best effect can be achieved with minimal investment. Of course, the primary ammonia pipeline 9 can also be arranged in the first primary air pipeline 4, the second primary air pipeline 5, the third primary air pipeline 6 and the fourth primary air pipeline 7 respectively. The primary ammonia pipeline 9 on each primary air pipeline is independently controlled and can be individually controlled according to the combustion conditions of different areas to achieve the best ammonia co-combustion effect. An independent first probe group 16 needs to be arranged in each area where the primary ammonia pipeline 9 is arranged.

[0045] A secondary air duct 10 is provided at the lower end of the secondary combustion chamber 2, and a secondary ammonia duct 11 is provided on the secondary air duct 10. One end of the secondary ammonia duct 11 can be directly connected to the secondary air duct 10, or it can be arranged on the side wall of the secondary combustion chamber 2 around the secondary air duct 10. When arranged on the side wall of the secondary combustion chamber 2, one end of the secondary ammonia duct 11 can be provided with multiple outlets, which are distributed in a circular shape outside the outlet of the secondary air duct 10 and ensure that the secondary ammonia injection direction is consistent with the secondary air injection direction.

[0046] A plurality of ammonia nozzles distributed in the vertical direction are provided on the side of the secondary combustion chamber 2. The ammonia nozzles can be directly arranged on the side wall of the secondary combustion chamber 2, or a special ammonia injection structure can be provided inside the secondary combustion chamber 2.

[0047] The incinerator body 1 is divided into a drying section, a pyrolysis gasification section, a combustion section and a burnout section along the feed port to the other side. The first primary air duct 4, the second primary air duct 5, the third primary air duct 6 and the fourth primary air duct 7 are respectively arranged in the drying section, the pyrolysis gasification section, the combustion section and the burnout section.

[0048] Three to five ammonia nozzles are provided to inject ammonia gas or aqueous ammonia into the secondary combustion chamber 2. The flow rate of each layer of ammonia nozzles can be independently adjusted. In this embodiment, the ammonia nozzles include a first ammonia nozzle 12, a second ammonia nozzle 13, and a third ammonia nozzle 14. The first ammonia nozzle 12, the second ammonia nozzle 13, and the third ammonia nozzle 14 are arranged in equal intervals from bottom to top on the side of the secondary combustion chamber 2.

[0049] The primary ammonia pipeline 9 , the secondary ammonia pipeline 11 and the plurality of ammonia nozzles are all connected to the ammonia storage device 15 and are supplied with ammonia.

[0050] A first probe group 16 for detecting the flue gas temperature and the ammonia and oxygen concentrations in the flue gas is provided on the upper side of the combustion section; a second probe group 17 for detecting the ammonia, nitrogen oxide and oxygen concentrations in the flue gas is provided between the inlet of the secondary air duct 10 of the secondary combustion chamber 2 and the ammonia nozzle; a third probe group 18 for detecting the ammonia, nitrogen oxide and oxygen concentrations in the flue gas is provided at the outlet of the secondary combustion chamber 2.

[0051] Flow control valves are provided on the first primary air duct 4, the second primary air duct 5, the third primary air duct 6, the fourth primary air duct 7, the primary ammonia duct 9, the secondary air duct 10, the secondary ammonia duct 11, and the multiple ammonia nozzles. All flow control valves are connected to an automatic ammonia control device 19, which controls the opening and closing of the flow control valves. The first probe group 16, the second probe group 17, and the third probe group 18 are connected to the automatic ammonia control device 19 and upload the collected parameters to the automatic ammonia control device 19. The automatic ammonia control device 19 adjusts the flow rates of each ammonia inlet and ammonia nozzle based on the concentrations of ammonia, nitrogen oxides, and oxygen in the received flue gas to achieve sufficient combustion of ammonia and suppress the formation of nitrogen oxides.

[0052] The air in the first primary air duct 4, the second primary air duct 5, the third primary air duct 6, the fourth primary air duct 7, and the secondary air duct 10 is room temperature air or preheated air at 100-250° C. The air in the first primary air duct 4, the second primary air duct 5, the third primary air duct 6, the fourth primary air duct 7, and the secondary air duct 10 is normal air or oxygen-enriched air.

[0053] A control method for a waste incineration device with co-combustion of ammonia comprises the following steps:

[0054] S1. Close all ammonia inlets and start the co-burning ammonia waste incineration device according to the startup process of a common grate-type waste incinerator until the waste in the co-burning ammonia waste incineration device is stably burned.

[0055] S2. Open the ammonia nozzles in the secondary combustion chamber layer by layer from top to bottom, and adjust the ammonia injection rate of the ammonia nozzles through the ammonia automatic regulating device until the emissions of ammonia and nitrogen oxides in the combustion flue gas meet the standards.

[0056] S3. Open the inlet of the secondary ammonia pipeline and gradually increase the secondary ammonia flow rate to the set value. At the same time, increase the secondary air flow rate to keep the residual oxygen concentration in the combustion flue gas unchanged. During this period, adjust the ammonia supply of each layer of ammonia nozzles to ensure that the continued emission of ammonia and nitrogen oxides in the combustion flue gas meets the standards.

[0057] Among them, the molar ratio of the total flow rate of secondary ammonia to the secondary air flow rate does not exceed 8%, and the molar ratio of the primary ammonia to the primary air flow rate does not exceed 5%.

[0058] S4. After the combustion stabilizes, open the primary ammonia pipeline inlet and gradually increase the primary ammonia flow rate to the set value. At the same time, increase the primary air flow rate to keep the residual oxygen concentration in the combustion flue gas unchanged. During this period, continue to adjust the ammonia supply of each layer of ammonia nozzles to ensure that the emissions of ammonia and nitrogen oxides in the combustion flue gas meet the standards.

[0059] S5. During operation, the combustion efficiency of the ammonia co-combustion process is optimized through flow control, ensuring complete combustion while maintaining the emission standards of ammonia and nitrogen oxides.

[0060] 5.1. Read the flue gas temperature T1 and the ammonia concentration C in the flue gas in the first probe group 氨1 , oxygen concentration C 氧1 , take the time scale T S1 The time average value within is calculated and compared with the flue gas temperature control value A, ammonia concentration control value B and oxygen concentration control value C respectively.

[0061] When the flue gas temperature T1 is lower than the flue gas temperature control value A, the ammonia supply is reduced until the supply is completely stopped.

[0062] When the flue gas temperature T1 is greater than the flue gas temperature control value A, and the ammonia concentration C in the flue gas 氨1 When the ammonia concentration is greater than the control value B, reduce the ammonia supply to ammonia concentration C. 氨1 Less than the ammonia concentration control value B.

[0063] When the flue gas temperature T1 is greater than the flue gas temperature control value A, the ammonia concentration C in the flue gas 氨1 Less than the ammonia concentration control value B, oxygen concentration C氧1 When the oxygen concentration is greater than the control value C, increase the ammonia supply to ammonia concentration C 氨1 Reach ammonia control value B or oxygen concentration C 氧1 Dropped to less than the oxygen concentration control value C.

[0064] When the flue gas temperature T1 is greater than the flue gas temperature control value A, the ammonia concentration C in the flue gas 氨1 Less than the ammonia concentration control value B, oxygen concentration C 氧1 When the oxygen concentration is less than the control value C, the ammonia supply is maintained unchanged.

[0065] 5.2. Read the oxygen concentration C in the flue gas detected by the second probe group 氧2 , ammonia concentration C 氨2 and nitrogen oxide concentration C 氮氧化物 , take the time scale T S2 The time average value within the range is calculated and compared with the oxygen concentration control value D, the ammonia concentration control value E and the nitrogen oxide concentration control value F respectively.

[0066] When the oxygen concentration C 氧2 When the oxygen concentration is greater than the control value D, keep the secondary ammonia supply unchanged and reduce the secondary air supply to the oxygen concentration C 氧2 Until the value is less than the oxygen concentration control value D.

[0067] When the oxygen concentration C 氧2 Less than the oxygen concentration control value D, the ammonia concentration in the flue gas C 氨2 When the ammonia concentration is greater than the control value E, keep the secondary air supply unchanged and reduce the secondary ammonia supply until the ammonia concentration C 氨2 Less than the ammonia concentration control value E or oxygen concentration C 氧2 Greater than the oxygen concentration control value D.

[0068] When the oxygen concentration C 氧2 Less than the oxygen concentration control value D, the ammonia concentration in the flue gas C 氨2 Less than the ammonia concentration control value E, nitrogen oxide concentration C 氮氧化物 When the concentration of nitrogen oxides is greater than the control value F, keep the secondary air supply unchanged and increase the supply of secondary ammonia until the concentration of nitrogen oxides C 氮氧化物 Less than the nitrogen oxide concentration control value F or ammonia concentration C 氨2 Greater than the ammonia concentration control value E.

[0069] When the oxygen concentration C 氧2 Less than the oxygen concentration control value D, the ammonia concentration in the flue gas C 氨2 Less than the ammonia concentration control value E, nitrogen oxide concentration C 氮氧化物 When the concentration is less than the nitrogen oxide control value F, the supply of secondary air and secondary ammonia is maintained unchanged.

[0070] S6. When the device is ready to shut down, first gradually reduce the primary ammonia flow rate until it is completely closed, and then gradually reduce the secondary ammonia flow rate until it is completely closed. During this period, the flow rate of the ammonia nozzle is adjusted to ensure that the emissions of ammonia and nitrogen oxides meet the standards. After the primary ammonia and secondary ammonia are completely closed, close each ammonia nozzle layer by layer from bottom to top.

[0071] S7 Complete the shutdown of the co-burning ammonia waste incinerator according to the shutdown process of the ordinary grate-type waste incinerator, until the co-burning ammonia waste incinerator completely stops running and cools down.

[0072] This invention couples the utilization of ammonia as a fuel energy source into the waste incineration process, providing a new technical approach for the clean utilization of ammonia. In this invention, ammonia and primary air are thoroughly mixed before entering the grate, facilitating a full reaction between the two gases as they pass through the high-temperature material layer, thereby improving ammonia combustion efficiency. A secondary ammonia inlet, located near the secondary air inlet, replenishes ammonia deficiency in the primary air and adjusts the secondary ammonia supply based on the ammonia combustion profile as reflected by the flue gas composition, ensuring combustion efficiency. Residual ammonia that fails to fully combust reacts with nitrogen oxides generated under high-temperature conditions, reducing the nitrogen oxide content in the flue gas. The multi-layer ammonia nozzle arrangement allows for flexible adjustment of the amount and location of ammonia addition, ensuring complete nitrogen oxide removal without the need for additional nitrogen oxide removal equipment. This invention automatically adjusts and optimizes the mixed combustion process of ammonia and domestic waste, reducing human intervention and the risks associated with operator inexperience or operational errors. This invention can be implemented in existing grate-type waste incinerators through appropriate technical modifications, making it ideally suited for upgrading existing grate-type waste incinerators.

[0073] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the present profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical content disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent replacement and improvement of the above embodiments made according to the technical essence of the present invention, within the spirit and principles of the present invention, without departing from the content of the technical solution of the present invention, shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A control method for a waste incineration device for co-firing ammonia, the waste incineration device for co-firing ammonia comprising an incinerator body and a secondary combustion chamber, the lower end of the secondary combustion chamber being connected to a flue gas outlet at an upper end of the incinerator body, a grate being provided within the incinerator body, a first primary air duct, a second primary air duct, a third primary air duct, and a fourth primary air duct being sequentially provided at a bottom of the incinerator body below the grate, a primary ammonia pipe being provided on at least one of the first primary air duct, the second primary air duct, the third primary air duct, and the fourth primary air duct, a secondary air duct being provided on the lower end of the secondary combustion chamber, a secondary ammonia pipe being provided on the secondary air duct, and a plurality of ammonia nozzles distributed in a vertical direction being provided in the secondary combustion chamber; It is characterized by The following steps are involved: S1. Close all ammonia inlets and start the ammonia-co-fired waste incinerator according to the startup process of a common grate-type waste incinerator until the waste in the ammonia-co-fired waste incinerator is stably burned; S2. Open the ammonia nozzles in the secondary combustion chamber layer by layer from top to bottom, and adjust the ammonia injection rate of the ammonia nozzles through the ammonia automatic regulating device until the emission of ammonia and nitrogen oxides in the combustion flue gas meets the standards; S3. Open the inlet of the secondary ammonia pipeline and gradually increase the secondary ammonia flow rate to the set value. At the same time, increase the secondary air flow rate to maintain the residual oxygen concentration in the combustion flue gas unchanged. During this period, adjust the ammonia supply of the ammonia nozzles on each layer to ensure that the emission of ammonia and nitrogen oxides in the combustion flue gas continues to meet the standards; S4. After the combustion stabilizes, open the primary ammonia pipeline inlet and gradually increase the primary ammonia flow rate to the set value. At the same time, increase the primary air flow rate to maintain the residual oxygen concentration in the combustion flue gas unchanged. During this period, continue to adjust the ammonia supply of each layer of ammonia nozzles to ensure that the emissions of ammonia and nitrogen oxides in the combustion flue gas meet the standards. S5. During operation, the combustion efficiency of the ammonia co-combustion process is optimized through flow control, ensuring complete combustion while maintaining the emission standards of ammonia and nitrogen oxides; S6. When the device is ready to shut down, first gradually reduce the primary ammonia flow rate until it is completely shut off, then gradually reduce the secondary ammonia flow rate until it is completely shut off. During this period, the flow rate of the ammonia nozzle is adjusted to ensure that the emission of ammonia and nitrogen oxides meets the standards. After the primary ammonia and secondary ammonia are completely shut off, close each ammonia nozzle layer by layer from bottom to top; S7 Complete the shutdown of the co-burning ammonia waste incinerator according to the shutdown process of the ordinary grate-type waste incinerator, until the co-burning ammonia waste incinerator completely stops running and cools down.

2. The control method of the waste incineration device with co-firing ammonia according to claim 1, characterized in that: In step S3, the molar ratio of the total flow rate of secondary ammonia to the flow rate of secondary air does not exceed 8%, and the molar ratio of the flow rate of primary ammonia to the flow rate of primary air does not exceed 5%.

3. The control method of the waste incineration device with co-firing ammonia according to claim 1, characterized in that: The step S5 is specifically as follows: 5.

1. Read the flue gas temperature T1 and the ammonia concentration C in the flue gas in the first probe group 氨1 , oxygen concentration C 氧1 , take the time scale T S1 The time average value within the range is compared with the flue gas temperature control value A, the ammonia concentration control value B and the oxygen concentration control value C respectively; When the flue gas temperature T1 is lower than the flue gas temperature control value A, the ammonia supply is reduced until the supply is completely stopped; When the flue gas temperature T1 is greater than the flue gas temperature control value A, and the ammonia concentration C in the flue gas 氨1 When the ammonia concentration is greater than the control value B, reduce the ammonia supply to ammonia concentration C. 氨1 Less than the ammonia concentration control value B; When the flue gas temperature T1 is greater than the flue gas temperature control value A, the ammonia concentration C in the flue gas 氨1 Less than the ammonia concentration control value B, oxygen concentration C 氧1 When the oxygen concentration is greater than the control value C, increase the ammonia supply to ammonia concentration C 氨1 Reach ammonia control value B or oxygen concentration C 氧1 Dropped to less than the oxygen concentration control value C; When the flue gas temperature T1 is greater than the flue gas temperature control value A, the ammonia concentration C in the flue gas 氨1 Less than the ammonia concentration control value B, oxygen concentration C 氧1 When the oxygen concentration is less than the control value C, the ammonia supply is maintained unchanged; 5.

2. Read the oxygen concentration C in the flue gas detected by the second probe group 氧2 , ammonia concentration C 氨2 and nitrogen oxide concentration C 氮氧化物 , take the time scale T S2 The time average value within 30 min was compared with the oxygen concentration control value D, the ammonia concentration control value E and the nitrogen oxide concentration control value F respectively; When the oxygen concentration C 氧2 When the oxygen concentration is greater than the control value D, keep the secondary ammonia supply unchanged and reduce the secondary air supply to the oxygen concentration C 氧2 Until the value is less than the oxygen concentration control value D; When the oxygen concentration C 氧2 Less than the oxygen concentration control value D, the ammonia concentration in the flue gas C 氨2 When the ammonia concentration is greater than the control value E, keep the secondary air supply unchanged and reduce the secondary ammonia supply until the ammonia concentration C 氨2 Less than the ammonia concentration control value E or oxygen concentration C 氧2 Greater than the oxygen concentration control value D; When the oxygen concentration C 氧2 Less than the oxygen concentration control value D, the ammonia concentration in the flue gas C 氨2 Less than the ammonia concentration control value E, nitrogen oxide concentration C 氮氧化物 When the concentration of nitrogen oxides is greater than the control value F, keep the secondary air supply unchanged and increase the supply of secondary ammonia until the concentration of nitrogen oxides C 氮氧化物 Less than the nitrogen oxide concentration control value F or ammonia concentration C 氨2 Greater than the ammonia concentration control value E; When the oxygen concentration C 氧2 Less than the oxygen concentration control value D, the ammonia concentration in the flue gas C 氨2 Less than the ammonia concentration control value E, nitrogen oxide concentration C 氮氧化物 When the concentration is less than the nitrogen oxide control value F, the supply of secondary air and secondary ammonia is maintained unchanged.

4. The control method of the waste incineration device with co-firing ammonia according to claim 1, characterized in that: The incinerator body is divided into a drying section, a pyrolysis gasification section, a combustion section and a burnout section along the feed port to the other side, and the first primary air duct, the second primary air duct, the third primary air duct and the fourth primary air duct are respectively arranged in the drying section, the pyrolysis gasification section, the combustion section and the burnout section.

5. The control method of the waste incineration device with co-combustion of ammonia according to claim 1, characterized in that: The ammonia nozzles include a first ammonia nozzle, a second ammonia nozzle and a third ammonia nozzle, and the first ammonia nozzle, the second ammonia nozzle and the third ammonia nozzle are arranged at equal intervals from bottom to top on the side of the secondary combustion chamber.

6. The control method of the waste incineration device with co-firing ammonia according to claim 1, characterized in that: The primary ammonia pipeline, the secondary ammonia pipeline and the plurality of ammonia nozzles are all connected to an ammonia storage device, and the ammonia storage device supplies ammonia.

7. The control method of the waste incineration device with co-firing ammonia according to claim 4, characterized in that: A first probe group for detecting the flue gas temperature and the ammonia and oxygen concentrations in the flue gas is arranged on the upper side of the combustion section, a second probe group for detecting the ammonia, nitrogen oxide and oxygen concentrations in the flue gas is arranged between the secondary air duct of the second combustion chamber and the ammonia nozzle, and a third probe group for detecting the ammonia, nitrogen oxide and oxygen concentrations in the flue gas is arranged at the outlet of the second combustion chamber.

8. The control method of the waste incineration device with co-combustion of ammonia according to claim 7, characterized in that: The first primary air duct, the second primary air duct, the third primary air duct, the fourth primary air duct, the primary ammonia duct, the secondary air duct, the secondary ammonia duct and the multiple ammonia nozzles are provided with flow regulating valves and all the flow regulating valves are connected to the ammonia automatic regulating device and controlled by the ammonia automatic regulating device. The first probe group, the second probe group and the third probe group are connected to the ammonia automatic regulating device and upload the collected parameters to the ammonia automatic regulating device.

9. The control method of the waste incineration device with co-combustion of ammonia according to claim 1, characterized in that: The air in the first primary air duct, the second primary air duct, the third primary air duct, the fourth primary air duct and the secondary air duct is normal temperature air or preheated air of 100-250°C; the air in the first primary air duct, the second primary air duct, the third primary air duct, the fourth primary air duct and the secondary air duct is ordinary air or oxygen-enriched air.

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