High-efficiency waste incineration system and operation mode thereof

Abstract

The application discloses a kind of high-efficiency garbage incineration system and its operating mode, belong to garbage incineration power generation technical field, the garbage incineration technology of the present application external high-temperature heating surface, greatly improve garbage incineration project thermal efficiency, light and heat system is mainly high-temperature cycle, save light field space, provide feasibility for garbage incineration project+light and heat power generation, in addition, the present application increases two auxiliary cycles of full cycle and low-temperature cycle, can adapt to any working condition change, simultaneously, the system of " steam + steam collection " is guaranteed The efficient and stable operation of system, improve project operation length, avoid the electric energy supplied by the system become "garbage electricity".

Description

Technical Field

[0001] This invention belongs to the field of waste incineration power generation technology, specifically relating to a high-efficiency waste incineration system and its operation mode. Background Technology

[0002] Invention patent CN113356953A, "Solar Energy Coupled Waste Incineration Power Generation System," provides a solar energy coupled waste incineration power generation system, including a waste incineration system, a solar power generation system, a steam turbine power generation system, and a feedwater heating system. This patent employs: ① an oil-water heat exchanger replacing part of the economizer, increasing the system's feedwater volume; ② an oil-water heat exchanger replacing part of the superheater and reheater, increasing the system's main steam volume; ③ low main steam parameters, either 4MPa, 400℃ or 6.4MPa, 450℃, failing to achieve high-parameter applications; ④ energy cascade utilization, with low-grade heat replacing part of the low-temperature heater, saving steam extraction from the steam turbine. However, these technologies simply replace some heat exchange surfaces; while technically simple, the system is complex, and they do not address the core issues of energy conservation and efficiency improvement in waste incineration projects. This invention employs the following techniques: ① It adds high-temperature hot oil heat exchange steam without replacing any additional heating surfaces, further heating the original main steam and avoiding the biggest problem plaguing high-parameter waste-to-energy projects—high-temperature corrosion; ② Molten salt pool 3-cycle: the main cycle consists of a two-pool cycle of high-temperature molten salt pool and medium-temperature molten salt pool to achieve efficient utilization of high-quality energy and reject cascaded utilization; auxiliary cycle 1 consists of a three-pool cycle of high, medium, and low-temperature molten salt pools to achieve cascaded energy utilization; auxiliary cycle 2 is a supplementary cycle between the medium-temperature and low-temperature molten salt pools to quickly reduce the molten salt temperature for safe operation; ③ High-parameter operation, operating at 6.8MPa, 460℃~13MPa, and 540℃, greatly improving the project's thermal efficiency; ④ The feedwater distributor and feedwater header can short-circuit the high-pressure heater, allowing the entire system to operate without a high-pressure heater; ⑤ The main steam distributor and main steam header can short-circuit the superheater that enhances the main steam parameters, allowing the entire system to operate as a gas superheater. In summary, this patent and this patent have different problems: ① They solve different problems. This patent only adds heat to the original system but does not solve the problems of low efficiency of waste-to-energy generation and high-temperature corrosion; ② They have different application processes. This patent only adopts energy cascade utilization but does not use high-grade heat in efficient places; ③ They have different application ranges. This process is only applicable to main steam parameters below 6.4MPa and 450℃.

[0003] Utility model patent CN210118178U, entitled "Combined Power Generation System Based on Waste Incineration Waste Heat and Solar Thermal Power," provides a combined power generation system based on waste incineration waste heat and solar thermal power. This system includes a water supply system, a medium- and low-pressure steam turbine system, a tiered molten salt storage tank, a high-pressure steam turbine, and couplings. This patent employs the following techniques: ① adding a solar thermal system and a high-pressure steam turbine to the traditional waste-to-energy system to increase the project's power generation; ② using large and small head water pumps to handle varying operating conditions; ③ using a molten salt heat exchanger as a separate bypass, enabling short-circuit operation or tiered energy utilization. Theoretically, this patent can achieve highly efficient energy utilization at different levels, but in reality, it does not have this capability. Feasibility: ① Waste-to-energy projects serve cities and are generally located close to urban areas, some even in bustling city centers, making it impractical to deploy large-scale solar fields and unable to meet the high-load operating conditions described in this patent; ② Solar energy in most large cities is unstable, varying with the Earth's revolution and rotation, so the core of coupling solar and thermal energy in waste-to-energy projects lies in regulation, not utilization; ③ Humans have utilized solar energy technology for thousands of years, but solar energy is not stable. Due to its unstable nature, solar power generation is referred to as "waste electricity" in the industry. This utility model, by adopting this design, would make the power generation of the entire waste-to-energy project unstable, essentially turning it into waste electricity—a measure that a normal person would not adopt. The first invention mentioned above recognized the core issues of coupling—regulation and feasibility—but the second utility model did not.

[0004] In summary, under the overarching goals of carbon peaking and carbon neutrality, it is particularly important to empower the waste-to-energy incineration industry and give it a new mission. However, current waste-to-energy incineration technologies still rely on conventional technologies to incinerate waste for power generation. There is no technology that couples waste incineration with solar thermal technology for power generation. In other words, there is currently no waste incineration system and its operation mode that is similar to this invention, integrating safety regulation and high efficiency and stability. Summary of the Invention

[0005] To address the existing technical problems, the purpose of this invention is to provide a waste incineration system and its operation mode that can operate stably under multiple working conditions, utilizes solar thermal energy to avoid high-temperature corrosion, and employs high parameters to improve the overall thermal efficiency of the site.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A high-efficiency waste incineration system includes an incinerator connected to a first vertical flue, which is connected to a second vertical flue, which is connected to a third vertical flue, which is connected to an evaporator screen, which is connected to a horizontal flue, which is connected to a steam distribution manifold, which is connected to a molten salt superheater and a gas superheater, respectively. Both the molten salt superheater and the gas superheater are connected to the steam collection manifold, which is connected to a steam turbine generator set, which is connected to a condenser, and the condenser is connected to a low-pressure heater. The low-pressure heater is connected to the deaerator, the deaerator is connected to the feed water pump, the feed water pump is connected to the water distribution manifold, the water distribution manifold is connected to the high-pressure heater and the water collection manifold, the high-pressure heater is also connected to the water collection manifold, the water collection manifold is connected to the horizontal flue, the high-pressure heater is also connected to the low-temperature molten salt pool, the low-temperature molten salt pool is connected to the concentrating absorber, the molten salt superheater is also connected to the medium-temperature molten salt pool, the medium-temperature molten salt pool is connected to the high-pressure heater and the concentrating absorber, the concentrating absorber is connected to the high-temperature molten salt pool and the medium-temperature molten salt pool, and the high-temperature molten salt pool is connected to the molten salt superheater.

[0008] Furthermore, the portion below the chimney of the first vertical flue is a refractory material casting section, the remaining portion of the first vertical flue excluding the portion below the chimney to the second vertical flue is a weld overlay section, and the third vertical flue is a conventional water-cooled wall section.

[0009] Furthermore, the valves of the water distribution manifold and the water collection manifold are both quick-opening and closing types, with opening degrees including 100% and 0%; the valves of the steam distribution manifold are slow-speed adjustable opening and closing valves, with opening degrees ranging from 0% to 100%.

[0010] Furthermore, the heating surface of the horizontal flue includes a superheater, a reheater, a water-cooled wall, and an economizer.

[0011] Furthermore, the temperature of the high-temperature molten salt pool is not lower than 540°C, the temperature of the medium-temperature molten salt pool is not lower than 450°C, and the temperature of the low-temperature molten salt pool is not lower than 320°C, which meets the heating temperature requirements of the high-pressure heater.

[0012] The operation modes of the aforementioned high-efficiency waste incineration system include flue gas flow, water supply flow, and molten salt flow;

[0013] The flue gas path is as follows: the flue gas generated after the garbage is burned in the incinerator passes through the first vertical flue, the second vertical flue, the third vertical flue, the evaporation screen, and the horizontal flue in sequence to utilize the waste heat;

[0014] The feedwater flow is as follows: After the exhaust steam condenses into condensate in the condenser, it passes through the low-pressure heater for heating, the deaerator for deoxygenation, and the feedwater pump for pressurization before entering the distribution header. The opening of the distribution header and the collection header determines whether the high-pressure heater is short-circuited. The feedwater in the collection header flows through the heating surface of the horizontal flue on the pipe side. The main steam produced by the heating surface of the horizontal flue enters the distribution header to distribute the steam volume. ① During normal operation, the main flow is from the distribution header to the molten salt superheater, and then to the collection header. ② When solar thermal resources are affected, an auxiliary flow is added in addition to the main flow. The auxiliary flow is from the distribution header to the gas superheater, and then to the collection header. ③ When the solar thermal system is under maintenance, the main flow is shut down, and the auxiliary flow becomes the main flow. The collection header provides superheated steam to the turbine generator set for power generation. The exhaust steam after working enters the condenser to start the next cycle.

[0015] The molten salt process includes: ① The main cycle is that after the concentrating absorber absorbs heat from the light field, the photothermal energy is stored in the molten salt medium in the high-temperature molten salt pool, and then provides high-grade heat to the molten salt superheater before being stored in the medium-temperature molten salt pool. The molten salt in the medium-temperature molten salt pool returns to the concentrating absorber to start the next cycle; ② When it is a season with abundant superheated energy, based on the main cycle ①, some of the medium-temperature molten salt releases heat by passing through the medium-temperature molten salt pool, the high-pressure heater, the low-temperature molten salt pool, and the concentrating absorber in sequence, realizing cascade utilization; ③ When the photothermal system fails, the main cycle ① is cut off, and the molten salt releases heat by passing through the medium-temperature molten salt pool, the high-pressure heater, and the low-temperature molten salt pool in sequence.

[0016] Furthermore, during the water supply process, when the opening degree of both the water distribution manifold and the water collection manifold is 0%, the high-pressure heater is short-circuited, and the water supply flows directly from the water distribution manifold to the water collection manifold.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] 1) The external high-temperature heating surface of the waste incineration technology greatly improves the thermal efficiency of waste incineration projects;

[0019] 2) The solar thermal system mainly uses high-temperature circulation, which saves space in the solar field and provides feasibility for waste incineration projects combined with solar thermal power generation; in addition, two auxiliary circulations, full circulation and low-temperature circulation, are added to adapt to any changes in operating conditions;

[0020] 3) The "steam distribution + steam collection" system ensures the efficient and stable operation of the system, extends the project's operating time, and prevents the electricity supplied by the system from becoming "waste electricity";

[0021] 4) The first, second and third vertical flues adopt corresponding anti-corrosion technologies to effectively avoid high-temperature corrosion. Attached Figure Description

[0022] Figure 1This is a schematic diagram of the oxygen-enriched waste incineration power generation system in Embodiment 1 of the present invention;

[0023] In the diagram: 1-Incinerator, 2-First vertical flue, 3-Second vertical flue, 4-Third vertical flue, 5-Evaporator screen, 6-Horizontal flue, 7-Steam distribution manifold, 8-Molten salt superheater, 9-Gas superheater, 10-Steam collection manifold, 11-Steam turbine generator set, 12-Condenser, 13-Low-pressure heater, 14-Deaerator, 15-Feed water pump, 16-Water distribution manifold, 17-High-pressure heater, 18-Water collection manifold, 19-High-temperature molten salt pool, 20-Medium-temperature molten salt pool, 21-Low-temperature molten salt pool, 22-Concentrating solar absorber. Detailed Implementation

[0024] The embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the embodiments described herein are for illustration and explanation only and are not intended to limit the present invention. Furthermore, detailed descriptions of known technologies are omitted if they are unnecessary to illustrate the features of the present invention.

[0025] Example 1

[0026] The structure of an oxygen-enriched waste incineration power generation system of the present invention is as follows: Figure 1As shown, the system includes an incinerator 1, which is connected to a first vertical flue 2. The first vertical flue 2 is connected to a second vertical flue 3, and the second vertical flue 3 is connected to a third vertical flue 4. The third vertical flue 4 is connected to an evaporation screen 5. The portion of the first vertical flue 2 below the chimney is a refractory material casting section, and the remaining portion of the first vertical flue 2 excluding the portion below the chimney to the second vertical flue 3 is a welded section. The third vertical flue 4 is a conventional water-cooled wall section. The evaporation screen 5 is connected to a horizontal flue 6. 6 includes all conventional heating surfaces of a waste incineration project, including but not limited to superheaters, reheaters, water-cooled walls, and economizers. Horizontal flue 6 is connected to a steam distribution manifold 7. The valves in the steam distribution manifold 7 are slow-speed adjustable on / off valves with an opening degree of 0%~100%. The steam distribution manifold 7 is connected to a molten salt superheater 8 and a gas-fired superheater 9, respectively. Both the molten salt superheater 8 and the gas-fired superheater 9 are connected to a steam collection manifold 10. The steam collection manifold 10 is connected to a steam turbine generator set 11. The steam turbine generator set 11 is connected to a condenser 12. The condenser 12 is connected to... A low-pressure heater 13 is connected to a deaerator 14, which in turn is connected to a feed water pump 15. The feed water pump 15 is connected to a water distribution manifold 16, which is connected to a high-pressure heater 17 and a water collection manifold 18. The valves in both the water distribution manifold 16 and the water collection manifold 18 are quick-opening and closing types, with opening degrees of 100% and 0%. The high-pressure heater 17 is also connected to the water collection manifold 18, which is connected to a horizontal flue 6. The high-pressure heater 17 is also connected to a low-temperature molten salt. The low-temperature molten salt pool 21 is connected to the concentrating heat absorber 22, and the molten salt superheater 8 is also connected to the medium-temperature molten salt pool 20. The medium-temperature molten salt pool 20 is connected to the high-pressure heater 17 and the concentrating heat absorber 22 respectively. The concentrating heat absorber 22 is connected to the high-temperature molten salt pool 19 and the medium-temperature molten salt pool 20 respectively. The high-temperature molten salt pool 19 is connected to the molten salt superheater 8. The temperature of the high-temperature molten salt pool 19 is not lower than 540°C, the temperature of the medium-temperature molten salt pool 20 is not lower than 450°C, and the temperature of the low-temperature molten salt pool 21 is not lower than 320°C.

[0027] The operation modes of the aforementioned high-efficiency waste incineration system include flue gas flow, feedwater flow, and molten salt flow:

[0028] The flue gas path is as follows: the flue gas generated after the garbage is burned in the incinerator 1 passes through the first vertical flue 2, the second vertical flue 3, the third vertical flue 4, the evaporation screen 5, and the horizontal flue 6 on the shell side in sequence to utilize the waste heat.

[0029] The feedwater flow path is as follows: After the exhaust steam condenses into condensate in the condenser 12, it sequentially passes through the low-pressure heater 13 for heating, the deaerator 14 for deaeration, and the feedwater pump 15 for pressurization before entering the distribution manifold 16. The opening degree of the distribution manifold 16 and the collection manifold 18 determines whether the high-pressure heater 17 is short-circuited. When the opening degree of both the distribution manifold 16 and the collection manifold 18 is 0%, the high-pressure heater 17 is short-circuited, and the feedwater flows directly from the distribution manifold 16 to the collection manifold 18. The feedwater in the collection manifold 18 flows through the heating surface of the horizontal flue 6. The main steam produced by the heated surface enters the steam distribution header 7 to distribute the steam volume; ① During normal operation, the main flow is from the steam distribution header 7 to the molten salt superheater 8, and then to the steam collection header 10; ② When solar thermal resources are affected, an auxiliary flow is added in addition to the main flow, which is from the steam distribution header 7 to the gas superheater 9, and then to the steam collection header 10; ③ When the solar thermal system is under maintenance, the main flow is shut down, and the auxiliary flow becomes the main flow; the steam collection header 10 provides superheated steam to the turbine generator set 11 for power generation, and the exhaust steam after working enters the condenser 12 to start the next cycle.

[0030] The molten salt process includes: ① The main cycle is that after the concentrating absorber 22 absorbs heat from the light field, the photothermal energy is stored in the medium in the high-temperature molten salt pool 19, and after providing high-grade heat to the molten salt superheater 8, it is stored in the medium-temperature molten salt pool 20. The molten salt in the medium-temperature molten salt pool 20 returns to the concentrating absorber 22 to start the next cycle; ② When it is a season with abundant superheated energy, based on the main cycle ①, some of the medium-temperature molten salt releases heat by passing through the medium-temperature molten salt pool 20, the high-pressure heater 17, the low-temperature molten salt pool 21, and the concentrating absorber 22 in sequence, realizing cascade utilization; ③ When the photothermal system fails, the main cycle ① is cut off, and the molten salt releases heat by passing through the medium-temperature molten salt pool 20, the high-pressure heater 17, and the low-temperature molten salt pool 21 in sequence.

[0031] The waste incineration technology of this invention features an external high-temperature heating surface, which greatly improves the thermal efficiency of waste incineration projects. The solar thermal system is mainly based on high-temperature circulation, saving space in the solar field and providing feasibility for waste incineration projects combined with solar thermal power generation. In addition, two auxiliary circulations, full circulation and low-temperature circulation, are added to adapt to any changes in operating conditions. The "steam distribution + steam collection" system ensures the efficient and stable operation of the system, increases the project's operating time, and prevents the electricity supplied by the system from becoming "waste electricity." The first, second, and third vertical flues adopt corresponding anti-corrosion technologies to effectively avoid high-temperature corrosion.

[0032] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An operating mode of a high-efficiency waste incineration system, characterized in that: This includes the flue gas flow path, the feedwater flow path, and the molten salt flow path; The flue gas path is as follows: the flue gas generated after the garbage is burned in the incinerator (1) passes through the first vertical flue (2), the second vertical flue (3), the third vertical flue (4), the evaporation screen (5), and the horizontal flue (6) in sequence to utilize the waste heat; The feedwater flow is as follows: after the exhaust steam is condensed into condensate in the condenser (12), it passes through the low-pressure heater (13) for heating, the deaerator (14) for deaeration, and the feedwater pump (15) for pressurization before entering the water distribution manifold (16). The opening of the water distribution manifold (16) and the water collection manifold (18) determines whether the high-pressure heater (17) is short-circuited. The feedwater in the water collection manifold (18) passes through the heating surface of the horizontal flue (6) on the pipe side. The main steam produced by the heating surface of the horizontal flue (6) enters the steam distribution manifold (7) to distribute the steam volume. ① During normal operation, the main flow is from the steam distribution manifold (7) to the molten salt superheater (8) and then to the steam collection manifold (10). ② When the solar thermal resources are affected, an auxiliary flow is added in addition to the main flow. The auxiliary flow is from the steam distribution manifold (7) to the gas superheater (9) and then to the steam collection manifold (10). ③ When the solar thermal system is under maintenance, the main flow is shut down and the auxiliary flow becomes the main flow. The steam collector (10) provides superheated steam to the steam turbine generator set (11) for power generation, and the exhaust steam after working enters the condenser (12) to start the next cycle; The molten salt process includes: ① The main cycle is that after the concentrating heat absorber (22) absorbs heat from the light field, the photothermal energy is stored in the molten salt medium in the high-temperature molten salt pool (19), and after providing high-grade heat to the molten salt superheater (8), it is stored in the medium-temperature molten salt pool (20). The molten salt in the medium-temperature molten salt pool (20) returns to the concentrating heat absorber (22) to start the next cycle; ② When it is a season with abundant superheated energy, based on the main cycle ①, part of the medium-temperature molten salt passes through the medium-temperature molten salt pool (20) and the high-pressure heater in sequence. (17) Heat is released through a low-temperature molten salt pool (21) and a concentrating heat absorber (22) to achieve cascade utilization; ③ When the photothermal system fails, the main circulation ① is cut off, and the molten salt is released in sequence through a medium-temperature molten salt pool (20), a high-pressure heater (17), and a low-temperature molten salt pool (21); the temperature of the high-temperature molten salt pool (19) is not lower than 540°C, the temperature of the medium-temperature molten salt pool (20) is not lower than 450°C, and the temperature of the low-temperature molten salt pool (21) is not lower than 320°C.

2. The operation mode of the high-efficiency waste incineration system according to claim 1, characterized in that: During the water supply process, when the opening of both the water distribution manifold (16) and the water collection manifold (18) is 0%, the high-pressure heater (17) is short-circuited, and the water supply goes directly from the water distribution manifold (16) to the water collection manifold (18).

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