Flue gas waste heat modular recovery heat exchanger system of natural gas power generation device

Abstract

The invention belongs to the technical field of waste heat utilization, and particularly discloses a natural gas power generation device flue gas waste heat modular recovery heat exchanger system which comprises a fuel gas balance tank and a desalted water circulation unit, a natural gas power generation unit is connected to the fuel gas balance tank, and a denitration device is connected to a flue gas pipeline of the natural gas power generation unit. Two heat exchange boilers are connected to a flue gas outlet of the denitration device in series, the desalted water circulation unit comprises a desalted water tank, two water outlet pipes are connected to the desalted water tank in parallel, water pumps are arranged on the two water outlet pipes respectively, and the two water outlet pipes are communicated with water inlets of the two heat exchange boilers respectively. Steam outlets of the two heat exchange boilers are communicated with a regeneration gas heater and a reboiler respectively, the regeneration gas heater and the reboiler are both connected with an air cooler, the reboiler is provided with an anti-deposition assembly, and the air cooler is communicated with a water inlet of the desalted water tank. Compared with the prior art, flue gas waste heat cascade recovery and steam graded supply can be achieved, and the graded heat utilization requirement of the natural gas purification device is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of waste heat utilization, in particular to a modularized flue gas waste heat recovery heat exchanger system of a natural gas power generation device. BACKGROUND

[0002] Under the dual driving of global energy structure transformation and the "double carbon" target, as a relatively clean fossil energy, the efficient utilization of natural gas has become a research hotspot in the energy field. Natural gas internal combustion generator set, as the core equipment of distributed energy system, is a device that uses natural gas as fuel to generate electricity, which is composed of natural gas supply system, combustion chamber, generator and control system, and is widely used in power supply inconvenient scenes such as remote well site and small natural gas processing device. This kind of unit drives the internal combustion engine to work by burning the mixed gas of natural gas and air to generate electricity, and the power generation efficiency is generally between 30%-45%. The rest of the energy is discharged in the form of high-temperature flue gas. According to statistics, a 10MW natural gas generator set can produce about 150,000 standard cubic meters of flue gas with a temperature of 400-600℃ per hour, which contains heat accounting for 55%-70% of the total fuel energy, equivalent to the loss of about 6-8 tons of standard coal heat per hour.

[0003] However, for a long time, the energy value of high-temperature flue gas has not been effectively developed. In the traditional processing mode, the flue gas is directly discharged after simple environmental denitration treatment, resulting in a large amount of heat being wasted. In the natural gas exploration and purification industry, this energy waste presents the following characteristics: on the one hand, the waste heat of high-temperature flue gas is not recovered, resulting in inefficient use of primary energy; on the other hand, the regenerator and reboiler in the natural gas purification device need to consume additional energy, such as steam generated by a gas boiler, to meet the process heat demand, forming an unreasonable situation of "wasting heat on one side and consuming energy on the other side".

[0004] The existing generator set and waste heat recovery equipment also have the following defects: most of the traditional waste heat recovery systems are independently designed, which has poor adaptability to the flue gas parameters and load fluctuations of the generator set, resulting in redundant equipment and large occupied area; in addition, the existing waste heat recovery form is single, mostly using single-stage heat exchange to produce single-parameter steam, which is difficult to meet the graded heat demand of the purification device; and the desalted water system and the waste heat recovery device are separated, the water resource recycling rate is insufficient, and the operation cost is increased.

[0005] In addition, in the natural gas purification process, the natural gas contains H2S, organic sulfide and CO2 and other acid gases, among which H2S has high toxicity, and even at very low concentration, it can cause poisoning and death of personnel in a short time, and H2S and CO2 can form an acidic solution in the presence of water, causing serious chemical corrosion to the pipeline, valve, heat exchanger and other equipment. Therefore, desulfurization treatment is a key link in the natural gas purification process, and the amine desulfurization process is widely used due to its high efficiency and economy; the process is to form rich amine liquid by chemical reaction of amine liquid and acid components (H2S, CO2 and the like) in raw gas, and then realize amine liquid recycling by heating and analyzing in the regeneration system. As the core heat transfer equipment of the amine regeneration tower, the reboiler undertakes the key function of heating the rich amine liquid to the analysis temperature, and its running state directly affects the desulfurization efficiency and device energy consumption.

[0006] But in the long-term use process, the solid particles such as HSS crystallization and PVA polymer in the amine liquid in the liquid phase zone at the bottom of the reboiler shell will be settled to the bottom of the reboiler due to gravity, and gradually form the accumulated material mainly composed of solid particles, which is loose and flocculent at the initial stage, and gradually hardened and consolidated at the later stage. The existence of these accumulated materials will reduce the effective liquid phase volume, cause the liquid level control error in the shell, increase the liquid phase flow resistance, and reduce the heat transfer efficiency; in severe cases, the accumulated materials may block the rich amine liquid inlet pipe or the lean amine liquid outlet pipe, forcing the device to stop and clean.

[0007] In summary, the current natural gas power plant flue gas waste heat modular recovery heat exchanger system has the problems of serious energy waste, low system integration, and heat transfer efficiency reduction caused by the accumulation in the bottom liquid phase zone of the heat exchanger, therefore, it is urgent to develop an integrated system that can realize the step-by-step recovery of flue gas waste heat, the step-by-step supply of steam and the recycling of desalted water. Therefore, the present application proposes a natural gas power plant flue gas waste heat modular recovery heat exchanger system to make up for and improve the shortcomings of the prior art. SUMMARY

[0008] To solve the above technical problems, the present application provides a natural gas power plant flue gas waste heat modular recovery heat exchanger system to solve the technical problems proposed in the background art.

[0009] In order to achieve the above object, the technical scheme provided by the present application is as follows: a natural gas power generation device flue gas waste heat modularized recovery heat exchanger system, comprising a fuel gas balance tank and a desalted water circulating unit, the fuel gas balance tank is connected with a natural gas generator set, a denitration device is connected to a flue gas pipeline of the natural gas generator set, a first heat exchange boiler is connected to a flue gas outlet of the denitration device, a second heat exchange boiler is connected to an outlet pipeline of the first heat exchange boiler, the desalted water circulating unit comprises a desalted water tank, two water outlet pipes are connected in parallel to the desalted water tank, a first water pump and a second water pump are respectively arranged on the two water outlet pipes, one end of one of the water outlet pipes is communicated with a water inlet of the first heat exchange boiler, a regenerated gas heater is communicated with a steam outlet of the first heat exchange boiler, a first air cooler is connected to a steam outlet of the regenerated gas heater, the first air cooler is communicated with a water inlet of the desalted water tank, one end of the other water outlet pipe is communicated with a water inlet of the second heat exchange boiler, a reboiler is communicated with a steam outlet of the second heat exchange boiler, a second air cooler is connected to a gas outlet of the reboiler, and the second air cooler is communicated with a water inlet of the desalted water tank.

[0010] As a further improvement of the above scheme, a high-pressure steam branch is arranged in front of the steam inlet of the regenerated gas heater, a low-pressure steam branch is arranged in front of the steam inlet of the reboiler, and a flow regulating valve is arranged on each of the high-pressure steam branch and the low-pressure steam branch.

[0011] As a further improvement of the above scheme, the reboiler comprises a shell, the shell is divided into an upper part and a lower part, the upper part and the lower part of the shell are detachably connected, the upper part of the shell is provided with a steam inlet and a steam outlet, the lower part of the shell is provided with an amine liquid inlet, an exhaust port and an amine liquid outlet, an anti-deposition assembly is arranged at the amine liquid inlet, a partition plate is arranged in the shell, the partition plate is located in the upper part of the shell, heat exchange tube bundles are arranged in the shell, and an overflow plate is arranged in the shell, wherein the heat exchange tube bundles and the overflow plate are located in the lower part of the shell.

[0012] As a further improvement of the above scheme, the upper part and the lower part of the shell are flange-connected, a sealing gasket is arranged at the connection between the upper part and the lower part of the shell, a liquid level meter is flange-connected to the upper part of the shell, the liquid level meter is located on one side of the lower part of the shell, and the liquid level meter is a magnetic float liquid level meter.

[0013] As a further improvement of the above-mentioned scheme, the anti-silt assembly comprises a mounting shaft and a supporting shaft, one end of the mounting shaft and the supporting shaft penetrates the shell, the end of the mounting shaft penetrating the shell is fixedly connected with a bearing one, the outer ring of the bearing one is fixedly connected with the shell, the two ends of the supporting shaft are fixedly connected with bearings one, the outer rings of the bearings one at the two ends of the supporting shaft are fixedly connected with the shell on one side and the overflow plate respectively, the side of the mounting shaft penetrating the shell is fixedly connected with a driving wheel, the side of the supporting shaft penetrating the shell is fixedly connected with a driven wheel, the driving wheel and the driven wheel are meshed and connected, the mounting shaft is fixedly connected with an impeller, the impeller is located at the amine liquid inlet, and the supporting shaft is fixedly connected with a plurality of fan blades.

[0014] As a further improvement of the above-mentioned scheme, the overflow plate is provided with a cavity, and a defoaming assembly is arranged in the cavity, the defoaming assembly comprises a mandrel, one end of the mandrel is fixedly connected with the supporting shaft, the mandrel is fixedly connected with a bevel gear one, the bevel gear one is meshed and connected with a bevel gear two, the bevel gear two is fixedly connected with a rotating shaft, the other end of the rotating shaft penetrates the overflow plate, the end of the rotating shaft penetrating the overflow plate is fixedly connected with a bearing two, the outer ring of the bearing two is fixedly connected with the overflow plate, the end of the rotating shaft penetrating the overflow plate is fixedly connected with a defoaming fan, and the rotating shaft is fixedly connected with a supporting bearing in the middle part, and the outer ring of the supporting bearing is fixedly connected with the overflow plate.

[0015] Compared with the prior art, the present application has the following advantages: (1) The present application recovers and utilizes the flue gas generated by natural gas combustion through two heat exchange boilers connected in parallel after the flue gas denitration device, and exchanges heat with the desalted water and the flue gas waste heat to generate steam for different equipment, realizes the step-by-step recycling of the flue gas waste heat of the natural gas generator, improves the energy utilization rate, meets the heat demand of different equipment, and also realizes the recycling of the desalted water, saving water resources.

[0016] The steam inlet of the regenerator and the reboiler is provided with a steam shunt and a flow regulating valve, the opening of the flow regulating valve can be adjusted to control the supplement of high-pressure steam and low-pressure steam, and then the heating temperature of the regenerator and the reboiler can be controlled.

[0017] (2) By arranging the anti-silt assembly in the reboiler, the impeller and the mounting shaft are driven to rotate by the power of the amine liquid flow, the supporting shaft is driven to rotate on the bearing one by the cooperation of the driving wheel and the driven wheel, and the fan blades are driven to rotate, so that the amine liquid flows at high speed in the reboiler, the HSS crystallization and PVA polymer solid particles in the amine liquid are prevented from depositing and clogging, the disturbance of the amine liquid in the reboiler is realized, the heat exchange efficiency is improved, the operation stability of the reboiler is improved, the equipment failure is reduced, and the driving of the fan blades does not require additional power, which is energy-saving and efficient.

[0018] Each fan blade is positioned at a 25° angle to the vertical direction of the support shaft. This allows the fan blade to generate thrust on the amine liquid during rotation, causing vortices to form and propelling the amine liquid to flow. Simultaneously, it agitates the fixed particles in the amine liquid, allowing the agitated solid particles to be discharged from the amine liquid outlet along with the heat-exchanged amine liquid, thereby reducing the deposition of solid particles and thus lowering the frequency of equipment cleaning. The level gauge on the reboiler shell can reflect the liquid level inside the shell in real time, allowing operators to promptly monitor the material situation and prevent excessively high or low liquid levels from affecting the normal operation of the reboiler.

[0019] (3) The defoaming component on the overflow plate can promote the rapid discharge of H2S and CO2 released when the amine liquid is heated, thereby optimizing the separation effect of the gas-liquid mixture, enabling the gas and liquid to be separated and circulated more effectively, reducing the amount of liquid carried out by the gas, improving the gas quality, and enhancing the gas separation effect in the reboiler. Attached Figure Description

[0020] Figure 1 This is a process flow diagram of a modular heat exchanger system for waste heat recovery from flue gas in a natural gas power generation unit according to the present invention. Figure 2 This is a perspective view of the reboiler in a modular heat exchanger system for waste heat recovery of flue gas in a natural gas power generation unit according to the present invention. Figure 3 This is a front view of the reboiler in a modular heat exchanger system for waste heat recovery from flue gas in a natural gas power generation unit according to the present invention. Figure 4 for Figure 3 Sectional view at point AA; Figure 5 This is a partial cross-sectional view of the reboiler in a modular heat exchanger system for waste heat recovery from flue gas in a natural gas power generation unit according to the present invention. Figure 6 for Figure 5 Enlarged view of point B in the image; Figure 7 for Figure 5 Enlarged view of point C in the image; Figure 8 This is a front cross-sectional view of the reboiler in a modular heat exchanger system for waste heat recovery from flue gas in a natural gas power generation unit according to the present invention.

[0021] The reference numerals in the accompanying drawings include: 1. Fuel gas balance tank; 2. Natural gas generator set; 3. First heat exchange boiler; 4. Second heat exchange boiler; 5. Demineralized water tank; 6. First water pump; 7. Second water pump; 8. Regenerated gas heater; 9. First air cooler; 10. Reboiler; 1001. Shell; 1002. Steam inlet; 1003. Steam outlet; 1004. Amine liquid inlet; 1005. Exhaust port; 1006. Amine liquid outlet; 1007. Baffle plate; 1008. Heat exchange tube bundle; 1009. Overflow plate; 11. Second air cooler 12. Anti-sludge assembly; 1201. Mounting shaft; 1202. Support shaft; 1203. Bearing 1; 1204. Drive wheel; 1205. Driven wheel; 1206. Impeller; 1207. Fan blade; 13. Sealing gasket; 14. Level gauge; 15. Demisting assembly; 1501. Spindle; 1502. Helical gear 1; 1503. Helical gear 2; 1504. Rotating shaft; 1505. Bearing 2; 1506. Demisting fan; 1507. Support bearing; 16. High-pressure steam branch; 17. Low-pressure steam branch; 18. Flow regulating valve. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Example 1 A modular heat exchanger system for recovering waste heat from flue gas in a natural gas power generation unit, such as Figure 1 As shown, the system includes a fuel gas balance tank 1 and a demineralized water circulation unit. A natural gas generator set 2 is connected to the fuel gas balance tank 1. A denitrification device is connected to the flue gas pipe of the natural gas generator set 2. A first heat exchange boiler 3 is connected to the flue gas outlet of the denitrification device. A second heat exchange boiler 4 is connected to the outlet pipe of the first heat exchange boiler 3. The demineralized water circulation unit includes a demineralized water tank 5. Two outlet pipes are connected in parallel to the demineralized water tank 5. A first water pump 6 and a second water pump 7 are respectively installed on the two outlet pipes. One end of the outlet pipe is connected to the inlet of the first heat exchange boiler 3. A regenerated gas heater 8 is connected to the steam outlet of the first heat exchange boiler 3. A first air cooler 9 is connected to the steam outlet of the regenerated gas heater 8. The first air cooler 9 is connected to the inlet of the demineralized water tank 5. The other end of the outlet pipe is connected to the inlet of the second heat exchange boiler 4. A reboiler 10 is connected to the steam outlet of the second heat exchange boiler 4. A second air cooler 11 is connected to the outlet of the reboiler 10. The second air cooler 11 is connected to the inlet of the demineralized water tank 5.

[0023] A high-pressure steam branch 16 is provided in front of the steam inlet of the regenerative gas heater 8, and a low-pressure steam branch 17 is provided in front of the steam inlet of the reboiler 10, and a flow regulating valve 18 is provided on each of the high-pressure steam branch 16 and the low-pressure steam branch 17.

[0024] In the system, the flue gas generated by burning natural gas is recovered by the first heat exchange boiler 3 and the second heat exchange boiler 4, and the desalted water in the desalted water tank 5 is used to exchange heat with the waste heat of the flue gas, thereby generating high-pressure steam and low-pressure steam, respectively, which are used in the regenerative gas heater 8 and the reboiler 10, respectively, to exchange heat with the regenerative gas and the amine liquid in the regenerative gas heater 8 and the reboiler 10, respectively, and finally the exchanged steam is cooled by the first air cooler 9 and the second air cooler 11 and then flows back to the desalted water tank 5, thereby realizing the step-by-step recovery and utilization of the waste heat of the flue gas of the natural gas generator, improving the energy utilization rate, meeting the heat demand of different equipment, and realizing the recycling of the desalted water and saving water resources.

[0025] The complete use steps and working principles of the above embodiment are as follows: first, the natural gas enters the natural gas generator set 2 through the fuel gas balance tank 1, the flue gas generated by power generation is treated by the denitration device, the flue gas generated by the natural gas generator set 2 has a temperature of 400-500℃, the flue gas amount is 22500m 3 / h, and then enters the first heat exchange boiler 3 and the second heat exchange boiler 4 in sequence. The desalted water in the desalted water tank 5 is delivered to the first heat exchange boiler 3 and the second heat exchange boiler 4 through two parallel pipelines by the first water pump 6 and the second water pump 7, respectively, the high-pressure steam generated in the first heat exchange boiler 3 exchanges heat in the regenerative gas heater 8, the high-pressure steam generated in the first heat exchange boiler 3 has a specification of 0.5MPa, the exchanged steam enters the first air cooler 9 for cooling, and after being cooled into a liquid, it flows back to the desalted water tank 5; the low-pressure steam generated in the second heat exchange boiler 4 enters the reboiler 10 to exchange heat with the amine liquid in the reboiler 10, the exchanged steam enters the second air cooler 11 for cooling, and after being cooled into a liquid, it flows back to the desalted water tank 5. During the heat exchange process, the flow regulating valve 18 provided in front of the steam inlet of the regenerative gas heater 8 and the reboiler 10 can be adjusted to control the supplement amount of the high-pressure steam and the low-pressure steam, and thus the heating temperature of the regenerative gas heater 8 and the reboiler 10 can be controlled.

[0026] Example Two A natural gas power generation device flue gas waste heat modularized recovery heat exchanger system, as shown in Figures 2 to 8As shown, the reboiler 10 comprises a shell 1001, which is divided into an upper part and a lower part, and the upper part and the lower part of the shell 1001 are flange-connected, and a sealing gasket 13 is arranged at the connection of the upper part and the lower part of the shell 1001, and an access hole and a liquid level meter 14 are flange-connected to the upper part of the shell 1001, and the liquid level meter 14 is located on one side of the lower part of the shell 1001, and the liquid level meter 14 is a magnetic flap liquid level meter, and the upper part of the shell 1001 is provided with a steam inlet 1002 and a steam outlet 1003, and the lower part of the shell 1001 is provided with an amine liquid inlet 1004, an exhaust port 1005 and an amine liquid outlet 1006, and the amine liquid inlet 1004 is provided with an anti-deposition assembly 12, and the pressure of the amine liquid entering the amine liquid inlet 1004 is 0.15-0.25 MPa, and a partition plate 1007 is arranged in the shell 1001, and the partition plate 1007 is located in the upper part of the shell 1001, and a heat exchange tube bundle 1008 is arranged in the shell 1001, and an overflow plate 1009 is arranged in the shell 1001, and the heat exchange tube bundle 1008 and the overflow plate 1009 are located in the lower part of the shell 1001.

[0027] The anti-deposition assembly 12 comprises a mounting shaft 1201 and a supporting shaft 1202, one end of the mounting shaft 1201 and the supporting shaft 1202 penetrates the shell 1001, the one end of the mounting shaft 1201 penetrating the shell 1001 is fixedly connected with a bearing one 1203, the outer ring of the bearing one 1203 is fixedly connected with the shell 1001, the both ends of the supporting shaft 1202 are fixedly connected with the bearing one 1203, the outer rings of the bearing ones 1203 at the both ends of the supporting shaft 1202 are fixedly connected with one side of the shell 1001 and the overflow plate 1009 respectively, the one side of the mounting shaft 1201 penetrating the shell 1001 is fixedly connected with a driving wheel 1204, the one side of the supporting shaft 1202 penetrating the shell 1001 is fixedly connected with a driven wheel 1205, the driving wheel 1204 and the driven wheel 1205 are meshingly connected, the mounting shaft 1201 is fixedly connected with an impeller 1206, the impeller 1206 is located at the amine liquid inlet 1004, the supporting shaft 1202 is fixedly connected with a plurality of fan blades 1207, and the included angle between each fan blade 1207 and the vertical direction of the supporting shaft 1202 is 25°.

[0028] Wherein, the amine liquid is driven to rotate the impeller 1206 and the mounting shaft 1201 in the anti-silt assembly 12 when entering the shell 1001 from the amine liquid inlet 1004, and then the driven wheel 1205 connected with the driving wheel 1204 is driven to rotate the supporting shaft 1202 on the bearing one 1203, so as to drive the fan blade 1207 to rotate, realize the high-speed flow of the amine liquid in the reboiler 10, prevent the HSS crystallization and the PVA polymer in the amine liquid from depositing and clogging, and realize the disturbance of the amine liquid in the reboiler 10 to make it uniformly mixed, improve the heat exchange efficiency, improve the operation stability of the reboiler 10, reduce the equipment failure, and the driving of the fan blade 1207 does not need extra power, which is energy-saving and efficient; the fan blade 1207 is arranged at an angle of 25° with the vertical direction of the supporting shaft 1202, which can make the fan blade 1207 rotate while generating a thrust on the amine liquid along the direction of the supporting shaft 1202 and causing the amine liquid to generate a vortex, so as to push the amine liquid to flow, and at the same time, the solid particles in the amine liquid are agitated, so that the solid particles can be discharged with the amine liquid after heat exchange from the amine liquid outlet 1006, thereby reducing the deposition of the solid particles at the bottom of the shell 1001, and further reducing the frequency of the amine liquid inlet and outlet clogging and the reboiler cleaning due to the deposition of the particles; the liquid level meter 14 on the reboiler shell can reflect the liquid level in the shell 1001 in real time, so that the operator can timely master the material situation and prevent the liquid level from being too high or too low to affect the normal work of the reboiler.

[0029] As preferred, the overflow plate 1009 is provided with a cavity, and a defoaming assembly 15 is arranged in the cavity, the defoaming assembly 15 comprising a mandrel 1501, one end of the mandrel 1501 being fixedly connected with the supporting shaft 1202, a bevel gear one 1502 being fixedly connected with the mandrel 1501, a bevel gear two 1503 being meshingly connected with the bevel gear one 1502, a rotating shaft 1504 being fixedly connected with the bevel gear two 1503, the other end of the rotating shaft 1504 penetrating through the overflow plate 1009, an axle bearing two 1505 being fixedly connected with the one end of the rotating shaft 1504 penetrating through the overflow plate 1009, the outer ring of the axle bearing two 1505 being fixedly connected with the overflow plate 1009, a defoaming fan 1506 being fixedly connected with the one end of the rotating shaft 1504 penetrating through the overflow plate 1009, and a supporting bearing 1507 being fixedly connected with the middle part of the rotating shaft 1504, the outer ring of the supporting bearing 1507 being fixedly connected with the overflow plate 1009.

[0030] The defoaming assembly 15 on the overflow plate 1009 can promote the rapid discharge of H2S and CO2 separated out when the heat exchange tube bundle 1008 heats the amine liquid. The airflow generated when the defoaming fan 1506 rotates can break the bubbles of H2S and CO2 separated out when the amine liquid is heated, so that the H2S and CO2 gas is rapidly discharged from the exhaust port 1005 by breaking through the liquid surface, the content of the dissolved gas in the amine liquid is reduced, the separation effect of the gas-liquid mixture in the reboiler can be optimized, the gas and liquid can be more effectively separated and circulated, the amount of liquid carried out by H2S and CO2 is reduced, and the gas separation effect in the reboiler is enhanced. The support bearing 1507 also adds a support point to the rotating shaft 1504, improves the rigidity of the rotating shaft 1504, and prevents excessive bending deformation and vibration of the rotating shaft 1504 due to its own weight and load when rotating.

[0031] The following is the complete use steps and working principle of the above-mentioned embodiment: when in use, low-pressure steam enters from the steam inlet 1002 at the upper part of the reboiler 10, and the amine liquid enters from the amine liquid inlet 1004 at the lower part of the reboiler 10. When the amine liquid passes through the impeller 1206, the impeller 1206 drives the mounting shaft 1201 to rotate, and at the same time drives the driving wheel 1204 at one end to rotate, and then drives the driven wheel 1205 engaged with the driving wheel 1204 to drive the fan blades 1207 and the bevel gear one 1502 on the support shaft 1202 to rotate. Under the action of the fan blades 1207, the amine liquid is agitated and the particulate matter in the amine liquid is brought up, and the bevel gear one 1502 drives the bevel gear two 1503 to rotate, thereby driving the defoaming fan 1506 on the rotating shaft 1504 to rotate. When the low-pressure steam passes through the heat exchange tube bundle 1008 and exchanges heat with the amine liquid in the shell 1001, H2S and CO2 separated out after the amine liquid is heated and bubbles of H2S and CO2 rise after the amine liquid is heated, pass through the overflow plate 1009, and the H2S and CO2 gas is discharged from the exhaust port 1005, the bubbles of H2S and CO2 are broken by the defoaming fan 1506, the gas phase is discharged from the exhaust port 1005, and the liquid phase is discharged from the amine liquid outlet 1006 together with the agitated particulate matter and the heat-exchanged amine liquid. The low-pressure steam is cooled in the second air cooler 11 after heat exchange.

[0032] The above-mentioned is only an embodiment of the present application, and the specific structure and characteristics of the scheme known in the art are not described in detail. It should be pointed out that for those skilled in the art, without departing from the structure of the present application, a number of modifications and improvements can be made, which should be regarded as the protection scope of the present application, which will not affect the effect and practicality of the patent. The protection scope claimed in this application should be subject to the content of its claims, and the specific implementation mode and the like recorded in the specification can be used to explain the content of the claims.

Claims

1. A modular heat recovery heat exchanger system for flue gas waste heat from a natural gas power plant, characterized by, The application relates to a fuel gas balance tank (1) and a desalted water circulating unit, a natural gas generator set (2) is connected to the fuel gas balance tank (1), a denitration device is connected to a flue gas pipeline of the natural gas generator set (2), a first heat exchange boiler (3) is connected to a flue gas outlet of the denitration device, a second heat exchange boiler (4) is connected to an outlet pipeline of the first heat exchange boiler (3), the desalted water circulating unit comprises a desalted water tank (5), two water outlet pipes are connected in parallel to the desalted water tank (5), a first water pump (6) and a second water pump (7) are arranged on the two water outlet pipes respectively, one end of one of the water outlet pipes is communicated with a water inlet of the first heat exchange boiler (3), a regenerated gas heater (8) is communicated with a steam outlet of the first heat exchange boiler (3), a first air cooler (9) is connected to a steam outlet of the regenerated gas heater (8), the first air cooler (9) is communicated with a water inlet of the desalted water tank (5), one end of the other water outlet pipe is communicated with a water inlet of the second heat exchange boiler (4), a reboiler (10) is communicated with a steam outlet of the second heat exchange boiler (4), a second air cooler (11) is connected to an outlet of the reboiler (10), and the second air cooler (11) is communicated with a water inlet of the desalted water tank (5).

2. A modular heat exchanger system for recovering waste heat from flue gas of a natural gas power plant according to claim 1, characterized in that, A high-pressure steam branch (16) is arranged in front of a steam inlet of the regenerated gas heater (8), a low-pressure steam branch (17) is arranged in front of a steam inlet of the reboiler (10), and flow regulating valves (18) are arranged on the high-pressure steam branch (16) and the low-pressure steam branch (17).

3. A modular heat exchanger system for recovering waste heat from flue gas of a natural gas power plant according to claim 1, wherein, The reboiler (10) comprises a shell (1001), the shell (1001) is divided into an upper portion and a lower portion, the upper portion and the lower portion of the shell (1001) are detachably connected, the upper portion of the shell (1001) is provided with a steam inlet (1002) and a steam outlet (1003), the lower portion of the shell (1001) is provided with an amine liquid inlet (1004), an exhaust port (1005) and an amine liquid outlet (1006), an anti-accumulation assembly (12) is arranged at the amine liquid inlet (1004), a partition plate (1007) is arranged in the shell (1001), the partition plate (1007) is located in the upper portion of the shell (1001), heat exchange tube bundles (1008) are arranged in the shell (1001), and an overflow plate (1009) is arranged in the shell (1001), wherein the heat exchange tube bundles (1008) and the overflow plate (1009) are located in the lower portion of the shell (1001).

4. A modular heat exchanger system for recovering waste heat from flue gas of a natural gas power plant according to claim 3, wherein, The upper portion and the lower portion of the shell (1001) are flange-connected, sealing gaskets (13) are arranged at the connecting positions of the upper portion and the lower portion of the shell (1001), a liquid level meter (14) is flange-connected to the upper portion of the shell (1001), the liquid level meter (14) is located on one side of the lower portion of the shell (1001), and the liquid level meter (14) is a magnetic reed liquid level meter.

5. A modular heat exchanger system for recovering waste heat from flue gas of a natural gas power plant according to claim 3, wherein, The anti-silt assembly (12) comprises a mounting shaft (1201) and a supporting shaft (1202), one end of the mounting shaft (1201) and the supporting shaft (1202) penetrates the shell (1001), one end of the mounting shaft (1201) penetrating the shell (1001) is fixedly connected with a bearing one (1203), the outer ring of the bearing one (1203) is fixedly connected with the shell (1001), both ends of the supporting shaft (1202) are fixedly connected with the bearing one (1203), the outer rings of the bearing ones (1203) at both ends of the supporting shaft (1202) are fixedly connected with one side of the shell (1001) and the overflow plate (1009) respectively, the side of the shell (1001) penetrating the mounting shaft (1201) is fixedly connected with a driving wheel (1204), the side of the shell (1001) penetrating the supporting shaft (1202) is fixedly connected with a driven wheel (1205), the driving wheel (1204) and the driven wheel (1205) are meshedly connected, the mounting shaft (1201) is fixedly connected with an impeller (1206), the impeller (1206) is located at the amine liquid inlet (1004), and the supporting shaft (1202) is fixedly connected with a plurality of fan blades (1207).

6. A modular flue gas heat recovery heat exchanger system for a natural gas power plant according to claim 3, wherein, The overflow plate (1009) is provided with a cavity, and a defoaming assembly (15) is arranged in the cavity, the defoaming assembly (15) comprises a mandrel (1501), one end of the mandrel (1501) is fixedly connected with the supporting shaft (1202), the mandrel (1501) is fixedly connected with a bevel gear one (1502), the bevel gear one (1502) is meshedly connected with a bevel gear two (1503), the bevel gear two (1503) is fixedly connected with a rotating shaft (1504), the other end of the rotating shaft (1504) penetrates the overflow plate (1009), one end of the rotating shaft (1504) penetrating the overflow plate (1009) is fixedly connected with a bearing two (1505), the outer ring of the bearing two (1505) is fixedly connected with the overflow plate (1009), one end of the rotating shaft (1504) penetrating the overflow plate (1009) is fixedly connected with a defoaming fan (1506), the middle part of the rotating shaft (1504) is fixedly connected with a supporting bearing (1507), and the outer ring of the supporting bearing (1507) is fixedly connected with the overflow plate (1009).

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