Deaerator steam exhaust waste heat utilization device

Abstract

The utility model provides a deaerator steam exhaust waste heat utilization device which comprises a deaerator, a three-stage type steam exhaust heat exchange tower communicated with the deaerator, a circulating water pump communicated with the three-stage type steam exhaust heat exchange tower, and a sludge pipe connected with the circulating water pump. Wherein a first-stage heat exchange area, a second-stage heat exchange area and a third-stage heat exchange area are arranged in the three-stage dead steam heat exchange tower, the first-stage heat exchange area is communicated with a steam outlet of the deaerator, the second-stage heat exchange area is arranged above the first-stage heat exchange area, and the third-stage heat exchange area is arranged above the second-stage heat exchange area and is communicated with the circulating water pump. Based on the waste heat utilization device for the steam exhaust of the deaerator, the waste heat of the steam exhaust is fully recycled, the resistance to a sludge pipeline conveying pipeline can be reduced by 50% or above, and the energy consumption saving rate of sludge heat drying can be reduced by 4% or above.

Description

Technical Field

[0001] This utility model relates to the field of deaerator steam waste heat reuse, specifically to a deaerator steam waste heat utilization device. Background Technology

[0002] Sludge is a solid waste discharged during the sewage treatment process. It has a water content of about 80% and is characterized by high moisture content, high organic matter content, foul odor, and viscosity.

[0003] Thermal drying combined with incineration is one of the mainstream technical routes for sludge reduction and resource utilization. The high-temperature flue gas from incineration can be used in a waste heat boiler to generate steam required for sludge thermal drying, reducing the auxiliary fuel consumption for sludge treatment.

[0004] Deaerators are auxiliary equipment in waste heat boilers and are crucial for boiler feedwater treatment. Long-term operational experience with sludge drying and incineration shows that deaerators release large amounts of low-temperature exhaust steam during operation. Due to the low temperature and pressure of this exhaust steam, its utilization cost is high, and it is usually directly discharged, resulting in significant energy waste.

[0005] On the other hand, the high solids content of the sludge results in significant resistance during sludge pipeline transportation and low transportation stability, which affects the operational stability of the sludge drying and incineration system. Utility Model Content

[0006] In view of the energy waste problem of deaerator steam exhaust in the above-mentioned prior art, as well as the disadvantages and deficiencies of high resistance in sludge pipeline transportation, this application provides a device for utilizing waste heat from deaerator steam exhaust.

[0007] To solve the above-mentioned technical problems, this utility model provides a waste heat utilization device for deaerator steam. The waste heat utilization device for deaerator steam includes: a deaerator, a three-stage waste steam heat exchange tower connected to the deaerator, a circulating water pump connected to the three-stage waste steam heat exchange tower, and a sludge pipe connected to the circulating water pump. The three-stage waste steam heat exchange tower is provided with a primary heat exchange zone, a secondary heat exchange zone, and a tertiary heat exchange zone. The primary heat exchange zone is connected to the steam outlet of the deaerator, the secondary heat exchange zone is located above the primary heat exchange zone, and the tertiary heat exchange zone is located above the secondary heat exchange zone and connected to the circulating water pump.

[0008] The waste heat utilization device for deaerator steam provided by this utility model may also have the following features: a steam-water separation structure and an exhaust port located above the steam-water separation structure are further provided at the top of the three-stage waste steam heat exchange tower, and the length-to-diameter ratio of the three-stage waste steam heat exchange tower is 8:1 to 3:1.

[0009] The waste heat utilization device for deaerator steam provided by this utility model may also have the following features: the steam-water separation structure is a metal wire mesh separator, an inertial separator, or a centrifugal separator.

[0010] The waste heat utilization device for deaerator steam provided by this utility model may also have the following features: the primary heat exchange zone includes a steam coil and a storage water. One end of the steam coil is connected to the steam outlet of the deaerator through a pipe, and the other end extends into the storage water. An exhaust hole is provided on the end that extends into the storage water. The storage water is connected to a circulating water pump.

[0011] The waste heat utilization device for deaerator steam provided by this utility model may also have the following features: the secondary heat exchange zone is set in the constriction zone of the three-stage waste steam heat exchange tower, including a liquid spraying plate, and liquid spraying holes are distributed on it. The ratio of the diameter of the constriction zone to the wide diameter of the three-stage waste steam heat exchange tower is 4:2 to 2:5.

[0012] The waste heat utilization device for deaerator steam provided by this utility model may also have the following features: the number of liquid-spraying plates is at least three, the three liquid-spraying plates are staggered in the constriction area, and the opening area of ​​the liquid-spraying plate accounts for 40% to 90% of the plate area.

[0013] The waste heat utilization device for deaerator steam provided by this utility model may also have the following features: one end of the circulating water pump is connected to a sleeve, which is wrapped around the outside of the sludge pipe; the three-stage heat exchange zone includes an atomizing spray pipe, one end of which is connected to the sleeve, and the other end extends into the interior of the three-stage waste steam heat exchange tower, and an atomizing nozzle is provided on the end that extends into the interior of the three-stage waste steam heat exchange tower.

[0014] The waste heat utilization device for deaerator steam provided by this utility model may also have the following feature: the diameter of the droplets after atomization by the atomizing nozzle is less than 0.5 mm.

[0015] The waste heat utilization device for deaerator steam provided by this utility model may also have the following feature: a partition is provided between the casing and the sludge pipe.

[0016] Compared with the prior art, the beneficial effects of the present invention are:

[0017] The waste heat utilization device and method for deaerator steam provided by this utility model includes a deaerator, a three-stage waste steam heat exchange tower, a circulating water pump, and a sludge pipe. The three-stage waste steam heat exchange tower is connected to the deaerator and contains a primary heat exchange zone, a secondary heat exchange zone, and a tertiary heat exchange zone. The waste steam discharged from the deaerator undergoes three heat exchanges within the three-stage heat exchange tower, transferring its waste heat to the primary heat exchange zone. Furthermore, the circulating water pump is connected to the three-stage heat exchange tower, and the transferred waste heat is used to connect to the sludge pipe, heating the sludge pipe. The heated circulating water then returns to the primary heat exchange zone through the tertiary heat exchange zone, achieving water circulation. Based on this deaerator steam waste heat utilization device, the waste heat is used to raise the temperature of the sludge, thereby reducing its flow resistance and fully realizing the reuse of the steam waste heat. This not only reduces the resistance of the sludge pipeline transportation pipeline by more than 50%, but also achieves an energy saving rate of more than 4% for sludge thermal drying.

[0018] In addition, the top of this three-stage exhaust steam heat exchange tower is equipped with a steam-water separation structure and an exhaust port located above the separation structure. The steam-water separation structure is a wire mesh separator, an inertial separator, or a centrifugal separator. This separation structure separates the non-condensable gases and atomized droplets in the exhaust steam after the three-stage heat exchange, and then the non-condensable gases are discharged out through the exhaust port.

[0019] In addition, the primary heat exchange zone includes a steam coil and a storage water, and the end of the steam coil that extends into the storage water is provided with an exhaust port. The exhaust steam discharged from the deaerator passes through the steam coil and is divided into small streams of air through the exhaust port on the steam coil, which then enter the storage water to perform primary heat exchange with the storage water.

[0020] In addition, the secondary heat exchange zone is a liquid-spraying plate, which is set in the constriction zone inside the heat exchange tower and is staggered in the exchange zone. Utilizing the structural characteristics of this staggered distribution, the exhaust steam after the primary heat exchange moves upward in an S-shaped flow pattern and undergoes intense secondary heat exchange with the water flow sprayed out by the liquid-spraying plate.

[0021] In addition, the tertiary heat exchange zone consists of atomizing spray pipes, one end of which is connected to a casing, and the other end is equipped with atomizing nozzles. The casing is connected to a circulating water pump and is wrapped around the outside of the sludge pipe. The water stored in the primary heat exchange zone carries the waste heat from the primary heat exchange and flows to the casing via the circulating water pump to heat the sludge pipe. The heated water is then sprayed out through the atomizing spray pipe and returns to the primary heat exchange zone, thus fully utilizing the waste heat of the exhaust steam to heat the sludge pipe while simultaneously achieving water circulation.

[0022] Furthermore, a baffle is installed between the sleeve and the sludge pipe to achieve uniform heating of the sludge pipe. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the deaerator steam waste heat utilization device in this embodiment;

[0024] Figure 2 This is a schematic diagram of the three-stage waste steam heat exchange tower in this embodiment;

[0025] Figure 3 This is a schematic diagram of the structure of the secondary heat exchange zone in this embodiment. Detailed Implementation

[0026] To make the technical problems solved, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0027] The waste heat recovery device for deaerator steam is used to exchange the waste heat of deaerator steam and use the exchanged waste heat to heat the sludge pipe, thereby improving the conveying performance of the sludge pipe.

[0028] like Figures 1 to 3 As shown, the waste heat recovery device for deaerator steam includes a deaerator 10, a three-stage waste steam heat exchange tower 20, a circulating water pump 30, and a sludge pipe 40. Additionally, in the attached... Figures 1 to 3 In the diagram, dashed line A indicates the flow direction of circulating water, dashed line B indicates the movement direction of waste heat steam, and solid black arrows indicate the transport direction of sludge.

[0029] As an auxiliary device of the waste heat boiler, the deaerator 10 discharges a large amount of steam during its operation.

[0030] like Figure 2 As shown, the three-stage waste steam heat exchange tower 20 is connected to the steam outlet of the deaerator 10. From bottom to top, the three-stage waste steam heat exchange tower 20 consists of a primary heat exchange zone 21, a secondary heat exchange zone 22, a tertiary heat exchange zone 23, a steam-water separation structure 24, and an exhaust port 25. Furthermore, the length-to-diameter ratio of the three-stage waste steam heat exchange tower 20 is 8:1 to 3:1.

[0031] The primary heat exchange zone 21 is located at the bottom of the three-stage exhaust steam heat exchange tower 20, and includes a steam coil 211 and a water storage 212.

[0032] Storage water 212 is filled at the bottom of the three-stage waste steam heat exchange tower 20. One end of the steam coil 211 extends out of the three-stage waste steam heat exchange tower 20 and is connected to the outlet of the deaerator 10; the other end extends into the storage water 212.

[0033] A number of vent holes are provided on the end of the steam coil 211 that extends into the storage water 212. These vent holes 213 are evenly distributed on the steam coil 211. The arrangement of these vent holes allows the exhaust steam entering the steam coil 211 to form multiple small airflows that enter the storage water 212 and exchange heat with the storage water 212.

[0034] The secondary heat exchange zone 22 is located in the central constriction zone 221 of the three-stage exhaust steam heat exchange tower 20, above the primary heat exchange zone 21. This constriction zone 221 is a protrusion extending outward from the inner wall of the three-stage exhaust steam heat exchange tower 20, resulting in a smaller diameter at this point. The ratio of the diameter of this constriction zone 221 to the diameter of the wide opening of the three-stage exhaust steam heat exchange tower 20 is 4:2 to 2:5.

[0035] like Figure 3 As shown, the secondary heat exchange zone 22 includes at least three staggered liquid-spraying discs 222. In this embodiment, there are three liquid-spraying discs 222, which are fixed sequentially at intervals from bottom to top on the constriction zone 221. The lowermost and uppermost liquid-spraying discs 222 are fixed on one side of the constriction zone 221, while the middle liquid-spraying disc 222 is fixed on the other side, allowing the three liquid-spraying discs 222 to be staggered. This staggered distribution of the liquid-spraying discs 222 structure allows the exhaust steam to flow in an S-shaped pattern as it passes through the liquid-spraying discs 222, enabling sufficient heat exchange.

[0036] In addition, the liquid distribution plate 222 is provided with several downward-facing liquid distribution holes 223. The water in the liquid distribution plate 222 flows out from the liquid distribution holes 223 and then comes into contact with the steam exhaust rising after the first heat exchange, thereby carrying out a second heat exchange. The total opening area of ​​all the liquid distribution holes 223 on the liquid distribution plate 222 accounts for 40% to 90% of the plate area.

[0037] The tertiary heat exchange zone 23 is located above the secondary heat exchange zone 22 and includes an atomizing spray pipe 231, one end of which extends outside the tertiary exhaust steam heat exchange tower 20. Several mist nozzles 232 are installed on one side of the pipe wall inside the tertiary exhaust steam heat exchange tower 20.

[0038] Water is filled into the atomizing spray pipe 231, and the water is atomized by the atomizing nozzle 232 and sprayed downwards, with the diameter of the sprayed droplets being less than 0.5 mm. The droplets undergo a third heat exchange with the exhaust steam after the secondary heat exchange, which moves upwards.

[0039] The steam-water separation structure 24 is located at the top of the three-stage waste steam heat exchange tower 20, above the three-stage heat exchange zone 23. The steam-water separation structure 24 can be a wire mesh separator, an inertial separator, or a centrifugal separator. Through this steam-water separation structure 24, steam-water separation is performed on the waste steam after three heat exchanges.

[0040] The exhaust port 25 is located above the steam-water separation structure 24. Non-condensable gases that have passed through the steam-water separation structure 24 are discharged from the exhaust port 25.

[0041] One end of the circulating water pump 30 is connected to the stored water 212 in the primary heat exchange zone 21 via a pipe, and the other end is connected to the sleeve 31. The sludge pipe 40 is used to transport sludge.

[0042] The sleeve 31 is wrapped around the outside of the sludge pipe 40, and a partition is also provided between it and the sludge pipe 40.

[0043] The sleeve 31 contains stored water that has undergone one heat exchange and has been pumped by the circulating water pump 30. The heat from this stored water can be used to heat the sludge pipe 40, and the baffles ensure uniform heating of the sludge pipe 40, reducing the transport resistance of the sludge pipe 40.

[0044] Furthermore, the other end of the sleeve 31 is connected to the atomizing spray pipe 231, so that the water stored inside can be sprayed out from the atomizing nozzle 232 after releasing heat, and finally fall back into the primary heat exchange zone 21 to achieve water circulation.

[0045] According to the waste heat utilization device and method for deaerator steam in the above embodiments, the device includes a deaerator, a three-stage waste steam heat exchange tower, a circulating water pump, and a sludge pipe. The three-stage waste steam heat exchange tower is connected to the deaerator and contains a primary heat exchange zone, a secondary heat exchange zone, and a tertiary heat exchange zone. The waste steam discharged from the deaerator undergoes three heat exchanges within the three-stage waste steam heat exchange tower, transferring the waste heat of the steam to the primary exchange zone. Furthermore, the circulating water pump is connected to the three-stage waste steam heat exchange tower, and the transferred waste heat is connected to the sludge pipe to heat the sludge pipe. The heated circulating water then returns to the primary heat exchange zone through the tertiary heat exchange zone, achieving water circulation. Based on this deaerator steam waste heat utilization device, the waste heat is used to raise the temperature of the sludge, thereby reducing its flow resistance and fully realizing the reuse of the steam waste heat. This not only reduces the resistance of the sludge pipeline transportation pipeline by more than 50%, but also achieves an energy saving rate of more than 4% for sludge thermal drying.

[0046] In addition, the top of this three-stage exhaust steam heat exchange tower is equipped with a steam-water separation structure and an exhaust port located above the separation structure. The steam-water separation structure is a wire mesh separator, an inertial separator, or a centrifugal separator. This separation structure separates the non-condensable gases and atomized droplets in the exhaust steam after the three-stage heat exchange, and then the non-condensable gases are discharged out through the exhaust port.

[0047] In addition, the primary heat exchange zone includes a steam coil and a storage water, and the end of the steam coil that extends into the storage water is provided with an exhaust port. The exhaust steam discharged from the deaerator passes through the steam coil and is divided into small streams of air through the exhaust port on the steam coil, which then enter the storage water to perform primary heat exchange with the storage water.

[0048] In addition, the secondary heat exchange zone is a liquid-spraying plate, which is set in the constriction zone inside the heat exchange tower and is staggered in the exchange zone. Utilizing the structural characteristics of this staggered distribution, the exhaust steam after the primary heat exchange moves upward in an S-shaped flow pattern and undergoes intense secondary heat exchange with the water flow sprayed out by the liquid-spraying plate.

[0049] In addition, the tertiary heat exchange zone consists of atomizing spray pipes, one end of which is connected to a casing, and the other end is equipped with atomizing nozzles. The casing is connected to a circulating water pump and is wrapped around the outside of the sludge pipe. The water stored in the primary heat exchange zone carries the waste heat from the primary heat exchange and flows to the casing via the circulating water pump to heat the sludge pipe. The heated water is then sprayed out through the atomizing spray pipe and returns to the primary heat exchange zone, thus fully utilizing the waste heat of the exhaust steam to heat the sludge pipe while simultaneously achieving water circulation.

[0050] Furthermore, a baffle is installed between the sleeve and the sludge pipe to achieve uniform heating of the sludge pipe.

[0051] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A device for utilizing waste heat from deaerator steam, characterized in that, include: Deaerator, A three-stage waste steam heat exchange tower, wherein the three-stage waste steam heat exchange tower is connected to the deaerator. A circulating water pump, which is connected to the three-stage waste steam heat exchange tower, The sludge pipe is connected to the circulating water pump. The three-stage exhaust steam heat exchange tower is equipped with a primary heat exchange zone, a secondary heat exchange zone, and a tertiary heat exchange zone. The primary heat exchange zone is connected to the steam outlet of the deaerator. The secondary heat exchange zone is located above the primary heat exchange zone. The tertiary heat exchange zone is located above the secondary heat exchange zone and is connected to the circulating water pump.

2. The deaerator exhaust steam waste heat utilization device according to claim 1, characterized in that: The top of the three-stage waste steam heat exchange tower is also equipped with a steam-water separation structure and an exhaust port located above the steam-water separation structure. The length-to-diameter ratio of the three-stage waste steam heat exchange tower is 8:1 to 3:

1.

3. The deaerator exhaust steam waste heat utilization device according to claim 2, characterized in that: The steam-water separation structure is a metal wire mesh separator, an inertial separator, or a centrifugal separator.

4. The deaerator exhaust steam waste heat utilization device according to claim 1, characterized in that: The primary heat exchange zone includes steam coils and water storage. One end of the steam coil is connected to the steam outlet of the deaerator via a pipe, and the other end extends into the stored water, with an exhaust port provided on the end extending into the stored water. The stored water is connected to the circulating water pump.

5. The deaerator exhaust steam waste heat utilization device according to claim 1, characterized in that: The secondary heat exchange zone is located in the constriction zone of the tertiary waste steam heat exchange tower, and includes a liquid spraying plate with liquid spraying holes distributed thereon. The ratio of the diameter of the constricted zone to the wide diameter of the three-stage waste steam heat exchange tower is 4:2 to 2:

5.

6. The deaerator exhaust steam waste heat utilization device according to claim 5, characterized in that: The number of the liquid-spraying discs is at least three, and the three liquid-spraying discs are staggered in the constriction area. The opening area on the liquid spraying tray accounts for 40% to 90% of the tray area.

7. The deaerator exhaust steam waste heat utilization device according to claim 1, characterized in that: One end of the circulating water pump is connected to a sleeve, which wraps around the outside of the sludge pipe; The three-stage heat exchange zone includes an atomizing spray pipe, one end of which is connected to the sleeve, and the other end extends into the interior of the three-stage exhaust steam heat exchange tower. An atomizing nozzle is provided on the end of the pipe that extends into the interior of the three-stage exhaust steam heat exchange tower.

8. The deaerator exhaust steam waste heat utilization device according to claim 7, characterized in that: The droplet diameter after atomization by the atomizing nozzle is less than 0.5 mm.

9. The deaerator exhaust steam waste heat utilization device according to claim 7, characterized in that: A partition is provided between the sleeve and the sludge pipe.

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