An incinerator energy recovery system

Abstract

The utility model discloses an energy recovery system for an incinerator, belonging to the technical field of energy recovery. The incinerator is connected to a dust collector installed on the side, a denitration reactor is installed on the side of the dust collector, an induced draft fan is installed on the side of the denitration reactor, a flue gas heat exchanger is connected to the denitration reactor, the flue gas heat exchanger is connected to the induced draft fan, and the induced draft fan is connected to a chimney. The system solves the problems of large energy consumption of the incinerator, emission loss of thermal deoxygenation steam, and low effective utilization rate, and is mainly used in energy recovery of incinerators.

Description

Technical Field

[0001] The utility model belongs to the technical field of energy recovery, in particular to an incinerator energy recovery system. Background Art

[0002] The treatment of waste gas and waste liquid from propylene oxide plants is a problem that must be faced in the production process of propylene oxide. Currently, propylene oxide plants use incinerators to incinerate the waste gas and waste liquid generated by the plant, so that the flue gas meets the emission standards.

[0003] Dissolved oxygen in boiler feed water can cause oxidative corrosion of boilers and related equipment. In order to prevent this phenomenon from happening, industrial boilers currently generally use thermal deoxygenation to deoxygenate boiler feed water. The principle is that when water is heated to the saturation temperature under the corresponding pressure, the steam partial pressure is close to the total pressure on the water surface, and the partial pressure of various gases dissolved in the water is close to zero. In this case, water does not have the ability to dissolve gases. The thermal deoxygenation system mainly includes a deaerator, a heat source (such as low-pressure steam) and connecting pipes. The deoxygenated water is transported to the incinerator by the boiler feed pump. After years of continuous technical improvements, thermal deoxygenation has the advantages of high deoxygenation efficiency, stable operation, good adaptability, and no harsh requirements on water quality and water temperature. However, since the water temperature needs to be heated to 102-104°C, the energy consumption is large, and there is emission loss in thermal deoxygenation steam, and the effective utilization rate is low. Utility Model Content

[0004] The utility model aims to provide an incinerator energy recovery system to solve the problems mentioned in the above background technology, namely, large energy consumption, emission loss of thermal deoxygenation steam and low effective utilization rate.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an incinerator energy recovery system, characterized in that a dust collector is installed on the side of the incinerator, a denitration reactor is installed on the side of the dust collector, an induced draft fan is installed on the side of the denitration reactor, a flue gas heat exchanger is connected to the denitration reactor, the flue gas heat exchanger is connected to the induced draft fan, and the induced draft fan is connected to the chimney;

[0006] The flue gas heat exchanger is connected to the membrane deoxygenation equipment, the flue gas heat exchanger is connected to the deaerator, a connecting pipe is arranged between the pipe connecting the flue gas heat exchanger and the membrane deoxygenation equipment and the pipe connecting the flue gas heat exchanger and the deaerator, a manual valve e is arranged on the connecting pipe, the deaerator uses desalted water to replenish the liquid level, the desalted water tee pipe is respectively connected to the deaerator and the membrane deoxygenation equipment, a regulating valve a, a manual valve c and a manual valve d are arranged on the desalted water tee pipe, the deaerator is connected to the water pump, the water pump is connected to the incinerator, a steam drum is arranged on the incinerator, the steam drum is connected to the superheater, a steam pipeline is installed on the superheater, a discharge pipe is installed on the deaerator, a discharge valve is installed on the discharge pipe, a thermometer is installed on the deaerator, a low-pressure inlet pipeline is installed on the deaerator, and a low-pressure steam regulating valve is installed on the low-pressure inlet pipeline.

[0007] Furthermore, a thermometer a is installed on the pipe connecting the incinerator and the dust collector, a thermometer b and a hand valve a are installed on the pipe connecting the flue gas heat exchanger and the denitrification reactor, and a thermometer c and a hand valve b are installed on the pipe connecting the flue gas heat exchanger and the induced draft fan.

[0008] Furthermore, the incinerator is a waste liquid incinerator.

[0009] Furthermore, the low-pressure inlet pipeline steam adopts 0.2-1.0MPag.

[0010] Compared with the prior art, the beneficial effects of the utility model are:

[0011] The utility model adopts membrane deoxygenation to deoxygenate, and deoxygenates through membrane components, with mild conditions and high deoxygenation efficiency; at the same time, it is easy to operate and maintain, occupies a small area, and can meet long-term stable operation. In addition, the membrane component can not only remove oxygen from water, but also has a good removal effect on carbon dioxide and other gases, avoiding secondary pollution to the environment. On the other hand, the process of the present invention is simple to operate and easy to switch. When there is a problem with the system, it can quickly switch to other working modes to ensure that the temperature operation of the device is not affected. Compared with the prior art, the thermal deoxygenation technology is replaced by membrane deoxygenation technology for deoxygenation, and the steam used for thermal deoxygenation is optimized to reduce steam loss; and the membrane deoxygenation equipment has a small investment and occupies a small space, effectively ensuring that the dissolved oxygen content of the outlet water is less than 15ppb, and ensuring the water quality requirements of the boiler feed water. On the other hand, a flue gas heat exchanger is added to the flue gas pipeline of the incinerator, and the low-temperature deoxygenated water produced by the membrane deoxygenation equipment is used to exchange heat with the high-temperature flue gas, further recovering the flue gas heat, while reducing the amount of low-pressure steam added to the deoxygenator and reducing the heat loss of flue gas. Recovering energy through this method can save millions of yuan per year. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a system diagram of the utility model.

[0013] In the figure: 1. Incinerator; 2. Steam drum; 3. Superheater; 4. Steam pipeline; 5. Dust collector; 6. Denitration reactor; 8. Thermometer b; 9. Hand valve a; 10. Hand valve b, 11. Thermometer c; 12. Induced draft fan; 13. Chimney; 14. Desalted water tee pipe; 15. Regulating valve a; 16. Membrane deoxygenation equipment; 17. Flue gas heat exchanger; 18. Hand valve c; 19. Hand valve d; 20. Low-pressure steam regulating valve; 21. Discharge valve; 22. Deaerator; 23. Water pump; 24. Thermometer; 25. Discharge pipe; 26. Connecting pipe; 27. Low-pressure inlet pipeline; 28. Thermometer a; 29. ​​Hand valve e; DETAILED DESCRIPTION

[0014] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0015] Example 1

[0016] In one embodiment, see Figure 1 The utility model provides a technical solution: a dust collector 5 is installed on the side of the incinerator 1, a denitration reactor 6 is installed on the side of the dust collector 5, a draft fan 12 is installed on the side of the denitration reactor 6, a flue gas heat exchanger 17 is connected to the denitration reactor 6, the flue gas heat exchanger 17 is connected to the draft fan 12, and the draft fan 12 is connected to the chimney 13.

[0017] In one embodiment, see Figure 1 The flue gas heat exchanger 17 is connected to the membrane deoxygenation device 16, the flue gas heat exchanger 17 is connected to the deaerator 22, the deaerator 22 uses desalted water to replenish the liquid level, the desalted water three-way pipe 14 is connected to the deaerator 22 and the membrane deoxygenation device 16 respectively, a connecting pipe 26 is set between the pipeline connecting the flue gas heat exchanger 17 and the membrane deoxygenation device 16 and the pipeline connecting the flue gas heat exchanger 17 and the deaerator 22, a manual valve e29 is set on the connecting pipe 26, and a regulating valve a is set on the desalted water three-way pipe 14 15. Manual valve c18 and manual valve d19, the deaerator 22 is connected to the water pump 23, the water pump 23 is connected to the incinerator 1, the incinerator 1 is provided with a steam drum 2, the steam drum 2 is connected to the superheater 3, the superheater 3 is installed with a steam pipeline 4, the deaerator 22 is installed with a discharge pipe 25, the discharge pipe 25 is installed with a discharge valve 21, the deaerator 22 is installed with a thermometer 24, the deaerator 22 is installed with a low-pressure inlet pipeline 27, and the low-pressure steam regulating valve 20 is installed on the low-pressure inlet pipeline 27.

[0018] In one embodiment, see Figure 1The flue gas generated by the incineration of the incinerator 1 is fed to the dust collector 5. After the dust is removed by the dust collector 5, the flue gas enters the denitration reactor 6. The flue gas after denitration is divided into two paths. One path directly enters the induced draft fan 12 through the flue gas pipeline, and the other path enters the induced draft fan 12 after heat exchange through the flue gas heat exchanger. The merged flue gas is sent to the chimney 13 through the induced draft fan 12. The deaerator 22 uses desalted water to supplement the liquid level. The desalted water is divided into two paths. One path directly enters the deaerator 22, and the other path first passes through the membrane deoxygenation equipment 16 and then passes through the flue gas heat exchanger 17, and enters the deaerator 22 after the flue gas is heated; the deaerator 22 controls the temperature of the deaerator 22 by supplementing low-pressure steam, and the material in the deaerator 22 is transported to the incinerator 1 through the boiler feed water pump 23, and enters the steam drum 2 after heat exchange in the incinerator 1 to produce 4.0MPag steam.

[0019] In one embodiment, see Figure 1 , install thermometer a28 on the pipe connecting the incinerator 1 and the dust collector 5, install thermometer b8 and hand valve a9 on the pipe connecting the flue gas heat exchanger 17 and the denitrification reactor 6, install thermometer c11 and hand valve b10 on the pipe connecting the flue gas heat exchanger 17 and the induced draft fan 12

[0020] In one embodiment, see Figure 1 The working mode of the above-mentioned incinerator energy recovery method is as follows: the flue gas from the incinerator 1 is monitored by the thermometer a28 to ensure that the flue gas temperature at the outlet of the incinerator 1 is 200±10℃. The flue gas first enters the dust collector 5 to remove the smoke generated by combustion, and then enters the denitration reactor 6 to remove nitrogen oxides in the flue gas. The flue gas at the outlet of the denitration reactor 6 is divided into two paths, one directly enters the induced draft fan 12, and the other enters the flue gas heat exchanger 17 to exchange heat with the low-temperature desalted water after membrane deoxygenation. The amount of flue gas entering the flue gas heat exchanger 17 is adjusted by the manual valve a9 and the manual valve b10. The flue gas after heat exchange enters the induced draft fan 12 again. After the two flue gases merge, they are sent to the chimney for discharge through the induced draft fan 12. The temperature of the flue gas before and after the flue gas heat exchange is monitored by the thermometer b8 and the thermometer c11. The temperature of the flue gas before the flue gas heat exchange is controlled at 200±10℃ by the thermometer b8, and the temperature of the flue gas after the flue gas heat exchange is controlled at 130±10℃ by the thermometer c11.

[0021] In one embodiment, see Figure 1The deaerator 22 maintains the liquid level by replenishing desalted water. The temperature of the desalted water fed is 25±5℃. Under normal circumstances, the manual valve c18 is opened and the manual valve d19 is closed. The amount of desalted water entering the membrane deoxygenation device 16 is adjusted by the regulating valve a15. The dissolved oxygen in the water is controlled within 15ppb after the desalted water passes through the membrane deoxygenation. The low-temperature desalted water after deoxygenation enters the flue gas heat exchanger 17 to exchange heat with the high-temperature flue gas. The temperature of the desalted water after the flue gas heating reaches 60±5℃. The desalted water after the flue gas heating enters the deaerator 22 again. The deaerator 22 maintains the temperature of the deaerator 22 by replenishing a small amount of low-pressure steam. The temperature of the deaerator 22 is monitored by the thermometer 24 and controlled at 105±3℃. The material in the deaerator 22 is then transported to the incinerator 1 through the boiler feed water pump 23 and heat-exchanged with the high-temperature flue gas to generate 4.0MPag steam in the drum 2.

[0022] In one embodiment, see Figure 1 When the flue gas heat exchanger 17 is abnormal or fails, first close the manual valve a9 and the manual valve b10 to cut the flue gas from the flue gas heat exchanger 17, then open the manual valve e29 to cut the flue gas heat exchanger 17 out, adjust the low-pressure steam regulating valve 20, and when the flue gas heat exchanger 17 returns to normal, cut the material into the flue gas heat exchanger 17 and resume the normal process.

[0023] See also Figure 1 When the membrane deoxygenation equipment 16 is abnormal or fails, first open the manual valve d19, then gradually close the manual valve c18, cut the desalted water out of the membrane deoxygenation equipment 16, adjust the discharge valve 21 of the deaerator 22, and deoxygenate by thermal deoxygenation. When the membrane deoxygenation equipment 16 returns to normal, cut the material into the membrane deoxygenation equipment 16 and resume the normal process.

[0024] In one embodiment, the energy recovery is adopted to effectively recycle and utilize the heat of high-temperature flue gas on the one hand, and use the flue gas to heat low-temperature desalted water, saving the use of low-pressure steam; on the other hand, membrane deoxygenation is adopted for deoxygenation, which can effectively reduce the emission of deaerator steam while ensuring water quality, thereby reducing energy consumption and reducing the risk of personal injury caused by steam emission.

[0025] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An incinerator energy recovery system, characterized in that: The incinerator (1) is connected to a dust collector (5) installed on the side of the dust collector (5), connected to a denitration reactor (6) installed on the side of the denitration reactor (6), connected to an induced draft fan (12), a flue gas heat exchanger (17) is connected to the denitration reactor (6), the flue gas heat exchanger (17) is connected to the induced draft fan (12), and the induced draft fan (12) is connected to a chimney (13); The flue gas heat exchanger (17) is connected to the membrane deoxygenation device (16), and the flue gas heat exchanger (17) is connected to the deoxygenator (22). A connecting pipe (26) is provided between the pipe connecting the flue gas heat exchanger (17) and the membrane deoxygenation device (16) and the pipe connecting the flue gas heat exchanger (17) and the deoxygenator (22). A manual valve e (29) is provided on the connecting pipe (26). The deoxygenator (22) uses desalted water to replenish the liquid level. The desalted water tee pipe (14) is respectively connected to the deoxygenator (22) and the membrane deoxygenation device (16). A regulating valve a (15), a manual valve e (29) are provided on the desalted water tee pipe (14). c (18) and a manual valve d (19), the deaerator (22) is connected to a water pump (23), the water pump (23) is connected to an incinerator (1), a steam drum (2) is arranged on the incinerator (1), the steam drum (2) is connected to a superheater (3), a steam pipeline (4) is installed on the superheater (3), a discharge pipe (25) is installed on the deaerator (22), a discharge valve (21) is installed on the discharge pipe (25), a thermometer (24) is installed on the deaerator (22), a low-pressure inlet pipeline (27) is installed on the deaerator (22), and a low-pressure steam regulating valve (20) is installed on the low-pressure inlet pipeline (27).

2. The incinerator energy recovery system according to claim 1, characterized in that: A thermometer a (28) is installed on the pipeline connecting the incinerator (1) and the dust collector (5), a thermometer b (8) and a manual valve a (9) are installed on the pipeline connecting the flue gas heat exchanger (17) and the denitration reactor (6), and a thermometer c (11) and a manual valve b (10) are installed on the pipeline connecting the flue gas heat exchanger (17) and the induced draft fan (12).

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