Indirect condensation water-lifting heat exchanger for wet flue gas
By using indirect condensation water heat exchanger of wet flue gas in the flue gas water extraction system, the water vapor in the wet flue gas is condensed by ambient cold air, the existing system has cumbersome process flow, low heat exchange efficiency and high energy consumption cost, and has achieved significant cost reduction and energy saving effects.
Patent Information
- Application Number
- CN202422091290.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-28
- Publication Date
- 2025-07-01
- Estimated Expiration
- 2034-08-28
AI Technical Summary
The existing flue gas water extraction system has cumbersome process, low heat exchange efficiency, large energy consumption and high equipment space occupancy, resulting in high power consumption per ton of water and large investment in ton of water during the operating cycle.
A wet flue gas indirect condensation water-exchanging heat exchanger is adopted, including a heat exchange shell, heat exchange element, axial fan and drainage tank. Through the indirect condensation of wet flue gas and ambient cold air, the moisture in the wet flue gas is collected, reducing operating power consumption and investment costs.
It has achieved the reduction of the project's operating electricity consumption ton of water, reduces the investment in water ton during the operating cycle, and improves the water saving effect. It is estimated that the unit of water recovery investment cost for operating units in 20 years is 1.47 yuan/t, and the unit of water recovery electricity consumption is 7.2KWh/t.
Smart Images
Figure CN223050465U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of flue gas water extraction systems, and in particular relates to a wet flue gas indirect condensation water extraction heat exchanger. Background Art
[0002] Fossil energy is the main energy source in my country, and coal-fired power plants using coal as raw materials still account for the majority of my country's electricity. Flue gas produced by coal combustion contains a large amount of water and low-grade heat after wet desulfurization. Recovering water from the flue gas after desulfurization is an important water-saving and energy-saving measure.
[0003] At present, the technologies for recovering water from flue gas mainly include indirect condensation method by heat exchanger, direct condensation method, membrane method, absorption method and other technical routes. Among them, only the direct condensation tower + indirect dry air cooling tower method has a few industrial application results. The direct condensation of the direct condensation tower + indirect dry air cooling tower method uses spray towers, packing towers, etc. as mass transfer and heat transfer equipment. The saturated flue gas is in direct contact with low-temperature circulating water, and condenses after heat exchange and cooling with the circulating water to achieve the purpose of collecting water. The cold source of low-temperature circulating water uses a dry air cooling tower. Practice has proved that the water-saving effect of the flue gas water extraction system is significant, which greatly reduces the amount of water resources consumed by the unit for power generation.
[0004] Although the direct condensation tower + indirect dry air cooling tower method has a significant water-saving effect, the low-temperature circulating water has been circulating in the system, and the necessary cleaning pH adjustment system must be equipped. Therefore, the process composition of the flue gas water extraction system consists of four parts: flue gas system, cooling device, cooling circulation system, cold source system, and pH adjustment system, and the system process is long. At the same time, due to the use of circulating water as an intermediate heat transfer medium, the heat needs to be exchanged twice through the direct condensation tower and the indirect dry air cooling tower before it can be discharged from the dry air cooling tower, so that the heat exchange temperature difference between the indirect dry air cooling tower and the air is small, and the equipment heat exchange area is large, resulting in high power consumption per ton of water in the entire project and large investment per ton of water during the operation cycle. Existing data show that the investment in a 660MW unit in the north with a flue gas water collection capacity of 90t / h is 50.56 million yuan. Based on the full life cycle of 20 years, the unit investment cost of recovered water is 6.12 yuan / t, and the unit operating cost of recovered water is 4.30 to 5.64 yuan / t. Utility Model Content
[0005] The purpose of the utility model is to solve the problems of complicated existing flue gas water extraction process, low heat exchange efficiency, high energy consumption cost and high equipment space occupancy rate, and to provide a wet flue gas indirect condensation water extraction heat exchanger, which can reduce the power consumption per ton of water in the project, reduce the investment per ton of water during the operation period, and improve the water-saving effect.
[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0007] A wet flue gas indirect condensation water extraction heat exchanger includes a heat exchange housing, on which there are cooperatively arranged a perforated plate, heat exchange elements, an axial flow fan, and a drain trough. The perforated plate is connected to both ends of the heat exchange housing for inlet and outlet of flue gas, the axial flow fan is connected to the top of the heat exchange housing, and the axial flow fan is arranged between the perforated plates on both sides;
[0008] The heat exchange element includes a group of heat exchange tubes, and a spiral guide vane is connected inside each heat exchange tube, and a group of fins are connected to the outside of the heat exchange tubes.
[0009] Further, the heat exchange tubes are inclined in the heat exchange housing, and the included angle between its axis and the horizontal direction is 2 to 20°.
[0010] Further, the guide vane is arranged in a spiral structure along the axis of the heat exchange tube.
[0011] Further, the fins are vertically connected to the outer wall of the heat exchange tube, and adjacent fins are parallel to each other.
[0012] Further, the drain trough is arranged facing the lowest point of the heat exchange tube, so as to collect the condensed water and discharge it from the drain trough.
[0013] In the technical solution of the present utility model, by collecting the moisture in the wet flue gas and using the ambient cold air to condense the water vapor in the saturated wet flue gas, the water-saving effect is achieved. At the same time, after the equipment of the present utility model is used, it is expected that the investment cost of the recovered water per unit of operation in 20 years is 1.47 yuan / t, and the power consumption for the operation of the recovered water per unit is 7.2 KWh / t, and the cost reduction and energy-saving effect is remarkable. Description of the Drawings
[0014] Figure 1 It is the front view of the wet flue gas indirect condensation water extraction heat exchanger of the present utility model;
[0015] Figure 2 It is the side view of the wet flue gas indirect condensation water extraction heat exchanger of the present utility model;
[0016] Figure 3 It is the structural schematic diagram of the heat exchange element of the present utility model. Detailed Embodiments Embodiment
[0017] To make the present utility model clearer and more understandable, the following further describes a wet flue gas indirect condensation water extraction heat exchanger of the present utility model with reference to the drawings. The specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.
[0018] See Figure 1 and Figure 2 , a wet flue gas indirect condensation water extraction heat exchanger includes a heat exchange housing 1, and is characterized in that:
[0019] On the heat exchange housing 1, there are cooperatively arranged a tube sheet 2, heat exchange elements 3, an axial flow fan 4 and a drain trough 5. Tube sheets 2 are provided at both ends of the heat exchange housing 1 for inlet and outlet of flue gas. A group of axial flow fans 4 are also connected to the top of the heat exchange housing 1, and the axial flow fans 4 are arranged between the tube sheets 2 on both sides;
[0020] Among them, the horizontal arrow represents saturated wet flue gas, and the vertical arrow represents surrounding cold air.
[0021] See Figure 1 and Figure 3 , the heat exchange elements 3 include a group of heat exchange tubes 31. The heat exchange tubes 31 are inclined in the heat exchange housing 1, and the included angle between their axes and the horizontal direction is 2 to 20°. The lowest point of the heat exchange tubes 31 is arranged directly opposite to the drain trough 5;
[0022] A flow guiding vane 32 is connected inside each heat exchange tube 31, and the flow guiding vane 32 is arranged in a spiral structure along the axis of the heat exchange tube 31;
[0023] A group of fins 33 are connected to the outside of the heat exchange tubes 31. The fins 33 are perpendicularly connected to the outer wall of the heat exchange tubes 31, and adjacent fins 33 are parallel to each other.
[0024] Taking a 660 MW unit in the north as an example, the saturated net flue gas volume is 2437172 Nm 3 / h, the temperature is 50 °C, 12.17%, the water collection amount is 90 t / h, the flue gas discharge temperature is 43.5 °C, 8.75%, and it is designed for ambient air at 20 °C.
[0025] The detailed parameters of the wet flue gas indirect condensation water extraction heat exchanger of the present utility model are as follows in the table:
[0026]
[0027] The heat exchanger of the present utility model is mainly applied to save water in wet flue gas purification. The water vapor in the saturated wet flue gas is condensed by ambient cold air to achieve the water saving effect. It can reduce the high power consumption per ton of water in the project operation, reduce the investment per ton of water during the operation period, and save costs.
[0028] In addition to the above embodiments, the present utility model can also have other embodiments. All technical solutions formed by equivalent replacement or equivalent transformation fall within the protection scope required by the present utility model.
Claims
1. A wet flue gas indirect condensation water extraction heat exchanger, comprising a heat exchange shell (1), characterized in that: The heat exchange shell (1) is provided with a flower plate (2), a heat exchange element (3), an axial flow fan (4) and a drainage groove (5) that cooperate with each other. The flower plate (2) is connected to both ends of the smoke inlet and outlet of the heat exchange shell (1), the axial flow fan (4) is connected to the top of the heat exchange shell (1), and the axial flow fan (4) is arranged between the flower plates (2) on both sides. The heat exchange element (3) comprises a group of heat exchange tubes (31), each heat exchange tube (31) is connected to a spiral guide vane (32) inside, and each heat exchange tube (31) is connected to a group of fins (33) outside.
2. The wet flue gas indirect condensation water extraction heat exchanger according to claim 1 is characterized in that: The heat exchange tube (31) is arranged in an inclined manner in the heat exchange shell (1), and the angle between its axis and the horizontal direction is 2-20 degrees.
3. The wet flue gas indirect condensation water extraction heat exchanger according to claim 1 or 2, characterized in that: The guide blades (32) are arranged in a spiral structure along the axis of the heat exchange tube (31).
4. The wet flue gas indirect condensation water extraction heat exchanger according to claim 1 or 2, characterized in that: The fins (33) are vertically connected to the outer wall of the heat exchange tube (31), and two adjacent fins (33) are parallel to each other.
5. The wet flue gas indirect condensation water extraction heat exchanger according to claim 2, characterized in that: The drainage groove (5) is arranged directly opposite to the lowest point of the heat exchange tube (31).