Temperature matcher and heat supply system

Abstract

The invention discloses a temperature matcher and a heat supply system. The temperature matcher comprises a pipe body, and a high-pressure low-temperature chamber, a low-pressure high-temperature chamber and a mixing chamber are sequentially arranged in the pipe body; the high-pressure and low-temperature chamber accelerates and decompresses high-pressure steam to form high-speed jet flow; generating negative pressure in the low-pressure high-temperature chamber to suck low-pressure steam; the mixing chamber is used for fully mixing high-pressure steam jetted at a high speed and sucked low-pressure steam to realize exchange of momentum and heat, the low-pressure steam is sucked by means of high-pressure driving steam and high-speed steam flow generated by jet of the nozzle, and parameters (temperature, pressure and flow) of the mixed steam are stabilized to meet process requirements required by a user; due to the fact that the two paths of steam can be allowed to have large pressure difference change through jet mixing, compared with a common mode that different steam sources are subjected to pressure reduction firstly and then mixed, the phenomenon that pressure difference fluctuation is caused by pressure reducing valve adjusting precision or working condition changes and steam suffocation is caused by steam source temperature differences is eradicated.

Description

Technical Field

[0001] This invention relates to the field of heating system technology, and in particular to a temperature matching device and a heating system. Background Technology

[0002] Converting a condensing turbine unit into a heating turbine unit, if a desuperheating and pressure-reducing device is to be used, requires selecting a turbine stage with extraction steam close to the heating steam parameters (2.1 MPa / 300℃). However, the maximum industrial steam supply required for each unit after the conversion is 100 t / h of high-pressure cylinder extraction, plus an additional 200 t / h of externally supplied industrial steam at 2.1 MPa / 300℃. The original design flow rates of the extraction steam at each stage of the unit are clearly insufficient to meet this requirement. Therefore, steam can only be extracted from the unit's reheat cold section or reheat hot section.

[0003] After some reheat steam is extracted from the cold reheat section, the reduced steam flow rate in the boiler reheater system directly affects the heat transfer of the reheater tubes, potentially causing the tube wall temperature to rise and leading to metal overheating, endangering unit safety. According to calculations by the boiler manufacturer, the current unit's cold reheat section steam extraction rate under BMCR conditions should not exceed 80 t / h; otherwise, it will cause reheater overheating. Therefore, cold reheat section steam extraction cannot meet industrial steam extraction requirements. Directly supplying energy to the user from the hot reheat section after desuperheating and pressure reduction would not affect the boiler or turbine. However, the energy loss caused by the dual desuperheating method is greater, and the desuperheating and pressure reduction device struggles to balance the temperature and pressure of the cold and hot reheat sections. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is that the de-cooling and de-pressure device is difficult to balance the temperature and pressure of the reheat cold section and the reheat hot section.

[0005] The above-mentioned technical problems are solved by the following technical solution: The present invention proposes a temperature matching device, including a tube body, wherein a high-pressure low-temperature chamber, a low-pressure high-temperature chamber, and a mixing chamber are sequentially arranged in the tube body; The high-pressure low-temperature chamber accelerates and depressurizes the high-pressure steam to form a high-speed jet; negative pressure is generated in the low-pressure high-temperature chamber to draw in low-pressure steam. The mixing chamber is used to fully mix the high-pressure steam from the high-speed jet with the low-pressure steam being drawn in, thereby achieving the exchange of momentum and heat.

[0006] In a preferred embodiment of the temperature matching device of the present invention: the high-pressure low-temperature chamber has a nozzle component, and the high-pressure low-temperature steam forms a high-speed jet after passing through the nozzle.

[0007] In a preferred embodiment of the temperature matching device of the present invention: the nozzle component is a needle-type regulating valve, which can change the flow cross-sectional area of ​​the high-speed jet.

[0008] In a preferred embodiment of the temperature matching device of the present invention: an electric actuator is connected to the end of the tube body, and the electric actuator is capable of controlling the needle valve.

[0009] In a preferred embodiment of the temperature matching device of the present invention, the output end of the mixing chamber has a conical structure.

[0010] In a preferred embodiment of the temperature matching device of the present invention: the top of the high-pressure low-temperature chamber is connected to a first air inlet, and the low-pressure high-temperature chamber is connected to a second air inlet.

[0011] A heating system includes the temperature matching device described above, and a reheat cold section steam branch connected to a high-pressure low-temperature chamber. The reheating hot section steam branch is connected to the low-pressure high-temperature chamber. The output end of the mixing chamber is connected to an output pipeline.

[0012] In a preferred embodiment of the heating system of the present invention: a control unit is provided on the reheat cold section steam branch, the reheat hot section steam branch and the output pipeline, and the control unit includes a thermometer, an electric gate valve and a pressure gauge.

[0013] In a preferred embodiment of the heating system of the present invention: an electric regulating valve is further provided on the reheat hot section steam branch; In a preferred embodiment of the heating system described in this invention: a pressure transmitter, a thermocouple, and a safety valve are also provided on the output pipeline.

[0014] In a preferred embodiment of the heating system of the present invention, a DCS module is also included, wherein the electric gate valve, electric regulating valve, pressure transmitter, and thermocouple are all connected to the DCS module.

[0015] The beneficial effects of this invention are as follows: by using high-pressure driven steam, a high-speed steam flow generated by nozzle injection is used to draw in low-pressure steam, and the parameters (temperature, pressure, flow rate) of the mixed steam are stabilized to the process requirements required by the user; since injection mixing allows for a large pressure difference change between the two steam sources, compared with the general method of first reducing the pressure of different steam sources and then mixing them, it eliminates the pressure difference fluctuation caused by the adjustment accuracy of the pressure reducing valve or changes in operating conditions, as well as the "steam trapping" phenomenon of low-pressure steam due to the temperature difference of the steam source. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. Obviously, the drawings described below only relate to some embodiments of the present invention and are not intended to limit the present invention. Wherein: Figure 1 A top view of the tube body in this invention is shown; Figure 2 A schematic diagram of the tube body in this invention is shown; Figure 3 A cross-sectional view of the tube body in this invention is shown; Figure 4 A schematic diagram of the heating system in this invention is shown. Detailed Implementation

[0017] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0018] The terminology used in this invention is that which is currently widely used in the art in consideration of the function of the invention; however, these terms may vary according to the intent of those skilled in the art, precedent, or new technology in the art. Furthermore, specific terms may be chosen by the applicant, and in such cases, their detailed meanings will be described in the detailed description of the invention. Therefore, the terms used in this specification should not be construed as simple names, but rather based on their meanings and the overall description of the invention.

[0019] Reference Figures 1-3 This embodiment provides a temperature matching device, including a tube body 1, in which a high-pressure low-temperature chamber 11, a low-pressure high-temperature chamber 12, and a mixing chamber 13 are sequentially arranged. The high-pressure low-temperature chamber 11 accelerates and depressurizes the high-pressure steam to form a high-speed jet; negative pressure is generated in the low-pressure high-temperature chamber 12 to draw in low-pressure steam; The mixing chamber 13 is used to fully mix the high-pressure steam of the high-speed jet with the low-pressure steam drawn in, so as to achieve the exchange of momentum and heat. High-pressure, low-temperature steam enters the high-pressure, low-temperature chamber 11, and forms a high-speed jet when it enters the low-pressure, high-temperature chamber 12. The high-pressure, low-temperature steam and the low-pressure, high-temperature steam continue to flow into the mixing chamber 13. In the mixing chamber 13, the two steams with different pressures and temperatures are mixed to form steam at a specified temperature and pressure. Unlike the desuperheating and pressure-reducing device, the temperature control of the mixed steam does not use desuperheating water. Instead, the temperature of the mixed steam is controlled by adjusting the ratio of high and low-temperature steam. The temperature remains stable when the heat load flow rate changes.

[0020] Because jet mixing allows for a large pressure difference between the two steam sources, compared to the general method of first reducing pressure and then mixing different steam sources, it eliminates pressure difference fluctuations caused by changes in the adjustment accuracy of the pressure reducing valve or changes in operating conditions, as well as the "steam trapping" phenomenon of low-pressure steam due to the temperature difference of the steam source.

[0021] Furthermore, the high-pressure low-temperature chamber 11 has a nozzle component. After the high-pressure low-temperature steam passes through the nozzle, it forms a high-speed jet. By providing a nozzle component in the high-pressure low-temperature chamber 11, the high-pressure low-temperature steam entering the high-pressure low-temperature chamber 11 can be depressurized and accelerated by the nozzle component to form a high-speed jet, ensuring the formation of a stable negative pressure field in the low-pressure high-temperature chamber 12 and ensuring the continuous intake of low-pressure steam.

[0022] Furthermore, the nozzle component is a needle-type regulating valve 14, which can change the flow cross-sectional area of ​​the high-speed jet; the valve core axis of the needle-type regulating valve 14 coincides with the nozzle axis; the valve core can move axially, and by changing the gap adjustment range of 0.3mm-5mm with the nozzle throat, the flow cross-sectional area of ​​the high-speed jet can be changed, thereby making the high-pressure steam flow rate continuously adjustable in the range of 20t / h-80t / h, adapting to different heating load requirements, and able to quickly respond to changes in heat load.

[0023] Furthermore, an electric actuator 2 is connected to the end of the pipe body 1. The electric actuator 2 can control the needle valve 14. The output shaft of the electric actuator 2 is rigidly connected to the valve core rod of the needle valve 14 through a coupling. The valve core rod adopts a double guide structure to prevent radial offset. After receiving the control signal, the electric actuator 2 drives the valve core to move linearly along the axial direction to achieve precise control of the opening degree of the needle valve 14.

[0024] Furthermore, the output end of the mixing chamber 13 has a conical structure; this conical structure is used to rectify and accelerate the mixed steam, reduce the eddy current loss at the steam outlet, stabilize the output steam flow rate, and at the same time help improve the stability of steam pressure.

[0025] As an optional embodiment, the top of the high-pressure low-temperature chamber 11 is connected to a first air inlet 15, and the low-pressure high-temperature chamber 12 is connected to a second air inlet 16. The first air inlet 15 allows high-pressure low-temperature steam to enter the high-pressure low-temperature chamber 11, and the second air inlet 16 allows low-pressure high-temperature steam to enter the low-pressure high-temperature chamber 12.

[0026] A heating system includes the temperature matching device described above, and a reheat cold section steam branch 3 connected to a high-pressure low-temperature chamber 11. The reheating hot section steam branch 4 is connected to the low-pressure high-temperature chamber 12; The output end of the mixing chamber 13 is connected to the output pipe 5; The reheat cold section steam parameters are high pressure and low temperature (pressure 3.3 MPa, temperature 280℃). The reheat cold section steam branch 3 is connected to the first air inlet 15. The reheat hot section steam parameters are slightly lower pressure than the reheat cold section and high temperature (pressure 3.03 MPa, temperature 566℃). The reheat hot section steam branch 4 is connected to the second air inlet 16. All pipelines are sealed to the second air inlet 16 through flanges. The reheat cold section steam and the reheat hot section steam eventually form steam with a pressure of 2.1 MPa and a temperature of 300℃ when mixed. This ensures continuous and efficient intake of low-pressure steam, avoiding heating interruptions caused by flow interruptions. It achieves efficient mixing of high and low-pressure steam and cascaded energy utilization, solving the problems of high energy loss and poor adaptability in traditional mixing methods, and avoiding damage to downstream equipment caused by local overheating or parameter fluctuations. The "high-pressure jet injection of low-pressure steam" mode replaces the traditional "depressurization before mixing" process, eliminating the phenomenon of "steam trapping" in low-pressure steam, improving the steam recovery rate at the hot end of low-pressure reheat, and enhancing the overall energy utilization rate of the system.

[0027] Furthermore, control units 6 are provided on the reheat cold section steam branch 3, the reheat hot section steam branch 4 and the output pipeline 5. The control unit 6 includes a temperature gauge 61, an electric gate valve 63 and a pressure gauge 62. Pressure gauge 62 can display steam pressure directly, making it easy for on-site personnel to check and make a preliminary judgment on the pressure status; temperature gauge 61 can display steam temperature directly on-site, assisting in monitoring temperature parameters; electric gate valve 63 is used for system on / off control, and can cut off the steam passage when the equipment is under maintenance or malfunctions; it has dual functions of remote control and on-site manual operation. The temperature gauge 61 and pressure gauge 62 can be used to understand the operating parameters of each pipeline such as temperature and pressure in a timely manner, while the electric gate valve 63 can be used to control the pipeline flow in a timely manner and open or close the pipeline as needed for operation.

[0028] Furthermore, an electric regulating valve 64 is also installed on the reheat hot section steam branch 4; a pressure transmitter 65, a thermocouple 66, and a safety valve 67 are also installed on the output pipeline 5; the electric regulating valve 64 can regulate the fluid flow rate, pressure, or temperature of the reheat hot section steam branch 4; by changing the valve opening, the steam throughput can be continuously adjusted to adapt to changes in operating conditions; the pressure transmitter 65 can monitor the steam pressure in real time, and the thermocouple 66 can measure the steam temperature; the safety valve 67 automatically opens and releases steam when the system pressure exceeds the set value to ensure system safety.

[0029] As an optional embodiment, it also includes a DCS module 7, an electric gate valve 63, an electric regulating valve 64, a pressure transmitter 65, and a thermocouple, all of which are connected to the DCS module 7.

[0030] The DCS system can receive signals from various sensors and control electric actuators 2, electric valves, etc., to achieve automated and precise operation of the system and ensure stable matching of steam parameters. The electric regulating valve 64 can adjust the valve opening according to the DCS system command, accurately control the steam flow and pressure, and realize the dynamic adjustment of system parameters; the pressure transmitter 65 transmits the pressure signal to the DCS system, providing data support for the pressure regulation of the output pipeline 5; the thermocouple 66 provides the basis for temperature monitoring and regulation of the output pipeline 5 in the system. When the parameters deviate from the set value, the control system can change the driving steam flow by adjusting the electric gate valve 63 on the reheat cold section branch to ensure the stability of the output parameters; the sensor on the output pipeline 5 continuously feeds the parameter data back to the control system, forming a dynamic adjustment mechanism to cope with fluctuations in steam source pressure or changes in process load.

[0031] The system is fully adapted to the mixed heating needs of reheat cold and reheat hot steam in power plants, providing reliable technical support for the energy-saving and automated upgrade of thermal systems. Its automated design and easy-to-maintain structure reduce manual intervention costs, improve operation and maintenance efficiency, and achieve dual optimization of economic and management benefits. The closed-loop control of DCS module 7 realizes full automation of parameter monitoring, adjustment, and alarm. The remote control functions of electric gate valve 63 and electric regulating valve 64 greatly shorten the fault response time, thereby reducing the need for operation and maintenance personnel and further reducing system maintenance costs.

[0032] Finally, it should be noted that the methods and devices described in detail above are merely embodiments, and those skilled in the art can modify these embodiments in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A temperature matching device, characterized in that: It includes a tube body (1), in which a high-pressure low-temperature chamber (11), a low-pressure high-temperature chamber (12), and a mixing chamber (13) are sequentially provided. The high-pressure low-temperature chamber (11) accelerates and depressurizes the high-pressure steam to form a high-speed jet; negative pressure is generated in the low-pressure high-temperature chamber (12) to draw in low-pressure steam; The mixing chamber (13) is used to fully mix the high-pressure steam of the high-speed jet with the low-pressure steam drawn in, so as to achieve the exchange of momentum and heat.

2. The temperature matching device according to claim 1, characterized in that: The high-pressure cryogenic chamber (11) has a nozzle component, and the high-pressure cryogenic steam forms a high-speed jet after passing through the nozzle.

3. The temperature matching device according to claim 2, characterized in that: The nozzle component is a needle-type regulating valve (14), which can change the flow cross-sectional area of ​​the high-speed jet.

4. The temperature matching device according to claim 3, characterized in that: The end of the tube (1) is connected to an electric actuator (2), which can control the needle valve (14).

5. The temperature matching device according to claim 4, characterized in that: The output end of the mixing chamber (13) has a conical structure.

6. The temperature matching device according to claim 5, characterized in that: The top of the high-pressure low-temperature chamber (11) is connected to a first air inlet (15), and the low-pressure high-temperature chamber (12) is connected to a second air inlet (16).

7. A heating system comprising the temperature matching device according to any one of claims 1-6, characterized in that: The reheat cold section steam branch (3) is connected to the high-pressure low-temperature chamber (11); The reheating hot section steam branch (4) is connected to the low-pressure high-temperature chamber (12); The output end of the mixing chamber (13) is connected to an output pipe (5).

8. The temperature matching device according to claim 7, characterized in that: The reheat cold section steam branch (3), the reheat hot section steam branch (4) and the output pipeline (5) are all equipped with a control unit (6), which includes a thermometer (61), an electric gate valve (63) and a pressure gauge (62).

9. The temperature matching device according to claim 8, characterized in that: An electric regulating valve (64) is also provided on the reheat hot section steam branch (4). The output pipeline (5) is also equipped with a pressure transmitter (65), a thermocouple (66), and a safety valve (67).

10. The temperature matching device according to claim 9, characterized in that: It also includes a DCS module (7), and the electric gate valve (63), electric regulating valve (64), pressure transmitter (65), and thermocouple are all connected to the DCS module (7).

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