A heat supply unit realizing heat supply stop without furnace stop

Abstract

The utility model discloses a kind of to realize heat supply unit of heat supply and stop furnace, set independent heat supply main steam pipeline, communicate boiler superheater and steam supply pipe network, realize furnace machine decoupling;With double system fuel supply structure, flexible switching pulverized coal and natural gas;With boiler forced water circulation auxiliary pipeline, guarantee low load water circulation stability;Steam turbine high-pressure cylinder entrance is equipped with isolation baffle, prevent steam leakage and cold air backflow;With flue gas waste heat recovery component and water temperature regulating tank, energy saving and stable steam parameter;With steam buffer tank, emergency water supply unit, guarantee supply pressure stability and boiler safety;Furnace is equipped with three-dimensional temperature monitoring network, optimization combustion;Steam turbine and generator are equipped with hydraulic clutch mechanism between, shorten overhaul time, all control components linkage central control system, realize automation operation, ensure that steam turbine stops when boiler continuous steam supply, improve heat supply continuity and unit reliability.

Description

Technical Field

[0001] This utility model relates to the field of heating equipment technology, specifically a heating unit that can ensure heating supply without shutting down the boiler during shutdown. It is suitable for urban centralized heating scenarios and can maintain continuous boiler operation and stable steam supply when the steam turbine is shut down. Background Technology

[0002] Existing heating units generally adopt a "boiler-turbine linkage" operation mode, meaning that when the steam turbine fails or is shut down for maintenance, the boiler must be stopped simultaneously, directly causing urban heating interruptions and affecting residents' lives and industrial production. This also has the following drawbacks: Single fuel supply: Relying primarily on pulverized coal or natural gas, these units are susceptible to fluctuations in fuel supply, such as pulverized coal shortages or natural gas outages, resulting in weak resilience; Unstable boiler water circulation: Natural water circulation is greatly affected by load changes, and localized water circulation stagnation can easily occur at low loads, leading to overheating and damage to the boiler tube walls; Waste of flue gas heat: High temperatures in the boiler tail flue... Direct emission of flue gas without effective waste heat recovery results in low energy utilization; insufficient turbine protection: after shutdown, there is no effective isolation device at the high-pressure cylinder inlet, which easily leads to steam leakage and cold air backflow, damaging internal turbine components; delayed emergency response: when the boiler drum water level is abnormal, water replenishment relies on manual operation, which can easily lead to water shortage accidents due to untimely response; inaccurate temperature monitoring: furnace temperature is mostly monitored at a single point, which cannot fully reflect the temperature field distribution and affects combustion optimization; low clutch efficiency: the turbine and generator are fixedly connected by a rigid coupling, and the coupling needs to be disassembled during shutdown maintenance, which takes a long time to separate / connect. Utility Model Content

[0003] This utility model aims to solve the problems of unstable fuel supply, poor water circulation, waste heat, insufficient turbine protection, and delayed water replenishment in existing heating units, and provides a heating unit that can ensure heating supply without shutting down the boiler during shutdown.

[0004] To achieve the above objectives, this utility model is implemented through the following technical solution:

[0005] This utility model discloses a heating unit that enables uninterrupted boiler operation during heating shutdowns. It includes a boiler body, a steam turbine, a generator, and an independent main steam pipeline. One end of the independent main steam pipeline is directly connected to the superheater outlet of the boiler body, and the other end is connected to the main steam supply pipe of the urban heating network through a steam distribution drum. An electric shut-off valve, a high-pressure reducing valve, a water spray desuperheater, and an electromagnetic flow control valve are installed in series on the independent main steam pipeline. All valves are connected to the central control system of the unit.

[0006] Preferably, the burner area of ​​the boiler body is configured with a dual-system fuel supply structure, which includes a group of pulverized coal burners and a natural gas burner symmetrically distributed around the furnace. The pulverized coal burners are connected to a pulverized coal conveying pipeline with a pulverized coal silo, and the natural gas burners are connected to a natural gas pipeline with a pressure regulating valve group. Both types of burners are equipped with independent ignition devices and flame detectors.

[0007] Preferably, it also includes a boiler forced water circulation auxiliary pipeline, one end of which is connected to the downcomer header of the boiler body, and the other end is connected to the riser header. A variable frequency circulation pump and a one-way check valve are installed on the pipeline. The speed of the variable frequency circulation pump is automatically adjusted by the unit's central control system according to the temperature difference between the downcomer and the riser.

[0008] Preferably, a sealed isolation baffle is provided at the high-pressure cylinder inlet of the steam turbine. The baffle is controlled to open and close by a hydraulic drive mechanism, which is connected to the steam turbine interlock protection system. When the steam turbine stops, the isolation baffle automatically closes to block steam from entering the steam turbine and prevent cold air backflow.

[0009] Preferably, a deep waste heat recovery component for flue gas is also provided. The deep waste heat recovery component for flue gas includes a finned heat exchanger installed in the flue at the tail end of the boiler. The cold side inlet of the heat exchanger is connected to the return water header of the urban heating network, and the cold side outlet is connected to the desuperheating section of the independent heating main steam pipeline. A bag filter that can be cleaned online is installed in front of the hot side inlet of the heat exchanger.

[0010] Preferably, a water temperature regulating tank is connected in series on the pipeline between the finned heat exchanger and the return water header. The regulating tank is equipped with a spiral stirring blade and a temperature sensor. The temperature sensor is linked with the electric regulating valve 1033, which can adjust the amount of return water entering the heat exchanger according to the water temperature at the heat exchanger outlet.

[0011] Preferably, a steam buffer tank 17 is installed downstream of the electromagnetic flow control valve of the independent heating main steam pipeline. A pressure transmitter is installed at the top of the buffer tank, and an automatic drain valve is provided at the bottom. The pressure transmitter collects the pressure inside the tank in real time and feeds it back to the central control system. When the pressure fluctuation exceeds ±0.05MPa, the unit's central control system automatically adjusts the opening of the electromagnetic flow control valve.

[0012] Preferably, it also includes a boiler emergency water supply unit, which includes a large-capacity water storage tank and a high-lift water supply pump. The water storage tank is connected to the boiler drum through a water supply pipeline. The high-lift water supply pump and a shut-off valve are installed sequentially on the water supply pipeline. The high-lift water supply pump is interlocked with the boiler drum water level gauge. When the water level is lower than the set value, water supply is automatically started.

[0013] Preferably, a three-dimensional temperature monitoring network is arranged on the inner wall of the furnace of the boiler body. The monitoring network consists of 12 high-temperature resistant thermocouples. The thermocouples are evenly distributed in layers along the height of the furnace, and all thermocouple signals are connected to the central control system of the unit.

[0014] Preferably, a hydraulic clutch mechanism is installed on the rigid coupling between the turbine and the generator. The hydraulic clutch mechanism includes an annular hydraulic cylinder and a position sensor. The annular hydraulic cylinder is connected to the hydraulic station through an oil pipe. The position sensor is used to detect the clutch status and transmit the signal to the central control system 6 of the unit, so as to realize the rapid separation or engagement of the turbine and the generator.

[0015] Beneficial effects: The independent main steam pipeline connects directly to the boiler superheater and the heating network, eliminating reliance on the steam turbine and ensuring continuous steam supply even when the turbine is shut down; the central control system links valves to precisely regulate steam pressure and flow, meeting heating parameter requirements; dual-fuel operation enhances resilience: five pulverized coal burners and four natural gas burners are symmetrically arranged, allowing for individual or mixed operation, avoiding the impact of fluctuations in single fuel supply; forced water circulation ensures boiler safety: the variable frequency circulating pump automatically adjusts its speed based on the temperature difference between the downcomer and riser pipes, maintaining stable water circulation and preventing localized overheating; finned heat exchangers recover waste heat from the tail flue to heat the return water, and bag filters ensure efficient heat exchange through online cleaning; the makeup water pump is interlocked with the steam drum level gauge, automatically starting makeup water when the water level falls below the set value, with a fast response time and no manual intervention required. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the independent heating main steam pipeline structure of this utility model.

[0017] Figure 2 This is a schematic diagram of the dual-system fuel supply structure of this utility model.

[0018] Figure 3 This is a schematic diagram of the auxiliary pipeline structure for forced water circulation in the boiler of this utility model.

[0019] Figure 4 This is a schematic diagram of the sealed isolation baffle structure of this utility model.

[0020] Figure 5 This is a schematic diagram of the structure of the flue gas waste heat deep recovery component of this utility model.

[0021] Figure 6 This is a schematic diagram of the boiler emergency water supply unit structure of this utility model.

[0022] Figure 7 This is a schematic diagram of the hydraulic clutch mechanism of this utility model. Detailed Implementation

[0023] The following will refer to the appendix in the embodiments of this utility model. Figure 1-7 The technical solutions in the embodiments of this utility model are clearly and completely described herein. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0024] In the description of the utility model, it should be noted that the terms "upper", "lower", "inner", "outer", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the device referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the utility model.

[0025] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "setting," "connection," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0026] The core structure of the independent heating main steam pipeline and its control system: The independent heating main steam pipeline 4 connects the boiler superheater outlet to the steam supply header, and is connected in series with an electric shut-off valve 42, a high-pressure reducing valve 43, a water spray desuperheater 44, and an electromagnetic flow control valve 45, and is connected to the central control system 6 via signal connection. Technical functions: Achieving "boiler-turbine decoupling": High-temperature, high-pressure steam generated by the boiler is directly delivered to the urban heating network without relying on the turbine, providing a core steam channel for "turbine shutdown, boiler uninterrupted operation"; the high-pressure reducing valve lowers the steam pressure to a network-compatible value, such as 1.0 MPa; the water spray desuperheater lowers the steam temperature to the heating demand, such as 250°C; and the electromagnetic flow control valve adjusts the steam supply according to the network load; the central control system receives valve and network parameter signals in real time and synchronously adjusts the actions of each valve to ensure stable steam supply pressure, temperature, and flow. This solves the key problem of "shutdown equals shutdown" in traditional units, ensuring continuous heating.

[0027] The core structure of the dual-fuel supply system includes: five sets of pulverized coal burners 71 and four natural gas burners 72 symmetrically distributed along the furnace; a pulverized coal silo 73 and a pulverized coal conveying pipeline 74; a pressure regulating valve group 75 and a natural gas pipeline 76; and independent ignition devices and flame detectors. It can use pulverized coal or natural gas alone, or a mixture thereof, avoiding boiler shutdown due to single fuel shortages such as pulverized coal supply interruptions or natural gas outages. Stable combustion is ensured: the pulverized coal burners obtain fuel from the pulverized coal silo through the conveying pipeline, and the natural gas burners maintain a stable gas supply pressure, such as 0.1 MPa, through the pressure regulating valve group. Combustion safety monitoring: the independent ignition device ensures a high ignition success rate, and the flame detector monitors the combustion status in real time, immediately cutting off the corresponding fuel in case of flameout to prevent deflagration. This ensures continuous boiler operation under different fuel supply conditions, providing a stable heat source for "shutdown without boiler interruption" and enhancing the unit's resilience.

[0028] The core structure of the boiler forced water circulation auxiliary pipeline includes: boiler forced water circulation auxiliary pipeline 8 (connecting the downcomer header and the riser header), variable frequency circulation pump 81, one-way check valve 82, and temperature difference regulation linkage with the central control system 6. Maintaining stable water circulation: After the turbine stops, the boiler load may decrease. The variable frequency circulation pump actively pressurizes the system to prevent natural water circulation from stagnating or flowing back under low load, thus preventing overheating and damage to the boiler tube walls. The central control system automatically adjusts the pump speed based on the temperature difference between the downcomer and riser, such as within a set range of 3-8℃. It increases the speed when the temperature difference is too large and decreases the speed when the temperature difference is too small, balancing water circulation efficiency and energy consumption. Preventing reverse water flow: The one-way check valve blocks reverse water flow within the pipeline, ensuring stable unidirectional operation of the circulation loop. Linked to overall objectives: Solving the boiler water circulation safety problem under low load, providing operational safety assurance for "shutdown without boiler shutdown".

[0029] The core structure of the turbine high-pressure cylinder sealed isolation baffle includes: a high-pressure cylinder inlet sealed isolation baffle 9, a hydraulic drive mechanism 91, and a connection to the turbine interlock protection system 92. It prevents steam from entering: When the turbine stops, the isolation baffle automatically closes to prevent boiler-side steam (even with minor leakage) from entering the high-pressure cylinder, avoiding accidental turbine rotation or component overheating damage during shutdown; it prevents cold air backflow: after closing, it forms a seal, blocking external cold air from flowing back into the turbine from the high-pressure cylinder inlet, preventing cold air from contacting internal high-temperature components and causing thermal shock or corrosion; it features automatic interlock control: the opening and closing of the isolation baffle can be executed by the hydraulic drive mechanism and is linked to the turbine interlock protection system. It automatically activates after a shutdown signal is triggered, requiring no manual operation and responding quickly. It protects the turbine from damage by steam and cold air, providing safe conditions for subsequent turbine restart or maintenance.

[0030] The core structure of the deep flue gas waste heat recovery component includes: a finned heat exchanger 101 at the boiler tail flue, the connection between the cold side and the return water header 16 and the desuperheating section 46 of the independent heating pipeline, and a bag filter 102 before the hot side inlet. Waste heat recovery from flue gas: High-temperature flue gas (200-300℃) flows through the hot side of the heat exchanger, transferring heat to the cold side's return water, raising the return water temperature from 40℃ to 60-80℃, reducing the boiler's heating load on steam and lowering energy consumption. The heated return water flows into the desuperheating section of the independent heating pipeline, mixing with the cooled steam to further stabilize the steam supply temperature and reduce boiler supplementary combustion requirements. The bag filter can clean dust online, removing dust from the flue gas and preventing dust from clogging the heat exchanger fins, ensuring continuous and effective waste heat recovery. This reduces boiler operating energy consumption and helps stabilize steam supply parameters.

[0031] The core structure of the water temperature regulating tank and its linkage control includes: a water temperature regulating tank 103 between the finned heat exchanger and the return water header; a spiral stirring blade 1031 and a temperature sensor 1032 inside the tank; and an electric regulating valve 1033 linked to the temperature sensor. Uniform water temperature: The spiral stirring blades agitate the return water entering the regulating tank, preventing fluctuations in the heat exchanger inlet water temperature due to temperature stratification. The temperature sensor monitors the heat exchanger outlet water temperature in real time. If the water temperature is too low (e.g., <60℃), the linked electric regulating valve opens wider to increase the return water flow and absorb more waste heat; if the water temperature is too high (e.g., >80℃), the valve closes to reduce the return water flow, ensuring the heat exchanger outlet water temperature remains stable within the suitable range. Stable mixing parameters: By controlling the return water temperature, the steam supply temperature after mixing with the steam from the independent heating pipeline is ensured to be stable, avoiding fluctuations in the pipeline network temperature. The flue gas waste heat recovery component achieves precise temperature control, further ensuring the stability of steam supply parameters in the "shutdown without boiler shutdown" mode.

[0032] The core structure of the steam buffer tank and pressure control system includes: a steam buffer tank 17 after the electromagnetic flow control valve of the independent heating pipeline, a top pressure transmitter 171, a bottom automatic drain valve 172, and pressure feedback regulation with the central control system 6. Stabilizing steam supply pressure: The buffer tank can temporarily store steam. When pipeline load fluctuations cause pressure changes, the pressure is balanced by the steam intake and exhaust within the tank, preventing sudden pressure rises and falls. The pressure transmitter collects the tank pressure in real time. If the fluctuation exceeds ±0.05MPa (e.g., the set value of 1.0MPa), the central control system automatically adjusts the opening of the electromagnetic flow control valve. When the pressure is too high, the valve closes to reduce steam supply; when the pressure is too low, the valve opens to increase steam supply. Condensate drainage: The bottom automatic drain valve periodically drains the condensate in the tank, preventing condensate from entering the pipeline network and affecting heating quality or causing water hammer in the pipeline. This solves the impact of pipeline load fluctuations on steam supply pressure under the "shutdown without boiler shutdown" mode, ensuring stable pressure in the urban heating pipeline network.

[0033] The core structure of the boiler emergency water replenishment unit includes: a large-capacity water storage tank 181, a high-lift water replenishment pump 182, a water replenishment pipeline 184, a water replenishment pump and shut-off valve on the pipeline 185, and an interlock with the boiler drum water level gauge. Emergency water replenishment guarantee: When the boiler drum water level falls below a set value, such as 50mm, the boiler drum water level gauge triggers an interlock signal, automatically starting the high-lift water replenishment pump and opening the shut-off valve to replenish water from the water storage tank to the boiler drum, preventing dry burning or pipe bursting due to boiler water shortage; rapid response: no manual operation is required; the water replenishment action is executed automatically with a response time of <30 seconds, solving the problem of lag in traditional manual water replenishment; the large-capacity water storage tank can store sufficient water, such as 50m³. 3 This ensures the boiler's emergency water replenishment needs are met within a short period, buying time for troubleshooting. In the "shutdown without boiler shutdown" mode, it guarantees a stable boiler drum water level, preventing forced boiler shutdown due to water shortage and maintaining continuous heating.

[0034] The core structure of the three-dimensional furnace temperature monitoring network consists of 12 high-temperature thermocouples (evenly distributed in three layers) on the inner wall of the furnace, connected to the central control system 6. Comprehensive temperature field monitoring: The 12 thermocouples cover the furnace height in three layers, enabling real-time acquisition of temperature data at different locations and heights within the furnace, avoiding the limitations of traditional single-point monitoring that cannot reflect localized high or low temperatures. Based on the temperature distribution feedback from the thermocouples, the central control system adjusts the fuel supply to the dual-mode burners; for example, reducing fuel in the corresponding area burner when the local temperature is too high, preventing furnace coking, excessive heat loss, or incomplete combustion. When the temperature in a certain area exceeds a safety threshold such as 1200℃, the system automatically issues an early warning, alerting maintenance personnel to investigate the fault. Through precise monitoring and optimized combustion, the system ensures the boiler's combustion efficiency and operational safety under the "shutdown without boiler shutdown" mode, reducing the risk of shutdown due to malfunctions.

[0035] The core structure of the hydraulic clutch mechanism between the turbine and generator includes: a ring hydraulic cylinder 231 on the rigid coupling 22, a position sensor 233, oil pipe connections between the hydraulic cylinder and the hydraulic station 235, and signal transmission between the position sensor and the central control system 6. Rapid separation / engagement: The ring hydraulic cylinder, through oil supply / return from the hydraulic station, drives the friction plate assembly to achieve rapid separation (≤5 seconds) or engagement between the turbine and generator, eliminating the need to disassemble the rigid coupling and significantly reducing maintenance or start-up / shutdown time. Clutch status monitoring: The position sensor monitors the piston position of the hydraulic cylinder in real time and feeds back the clutch status (separation / engagement) to the central control system, preventing abnormal unit operation due to incomplete clutch engagement. Ensuring operational safety: Hydraulic drive and electrical control interlocking prevent human error, ensuring smooth and safe clutch operation. In "shutdown without boiler interruption" mode, if the turbine needs maintenance, it can be quickly separated from the generator without affecting the generator (if standby operation is required) or shortening turbine maintenance time, indirectly ensuring the stability of continuous boiler operation.

[0036] The following describes in detail the specific implementation of this utility model in conjunction with the technical solution and component parameters. The model of each component can be adjusted according to the unit capacity (such as 300MW or 600MW), but the core logic remains the same.

[0037] 1. Overall Unit Architecture: The core of this heating unit consists of three basic components: boiler body 1, steam turbine 2, and generator 3, as well as nine improved structures: independent main steam pipeline 4, dual-system fuel supply structure, boiler forced water circulation auxiliary pipeline 8, sealed isolation baffle 9, flue gas waste heat deep recovery component 10, steam buffer tank 17, boiler emergency water supply unit, three-dimensional temperature monitoring network, and hydraulic clutch mechanism. All electrical control components are connected to the unit's central control system 6, model: DCS-3000, to achieve coordinated control.

[0038] 2. Implementation details of each core structure

[0039] The connection relationship of the independent heating main steam pipeline 4 is as follows: one end is welded to the superheater outlet 11 of the boiler body 1 via a flange, and the other end is connected to the steam distribution drum 41 with a volume of 5m³. 3 It is connected to the steam supply main pipe 5 of the city heating network; Pipeline components: along the steam flow direction, an electric shut-off valve 42 (model J941H-16C), a high-pressure reducing valve 43 (model Y43H-25), a water spray desuperheater 44 (model SJG-100), and an electromagnetic flow control valve 45 (model LDB-50) are connected in series; Control logic: the central control system 6 adjusts each valve in real time according to the pressure setpoint of 1.0MPa and the temperature setpoint of 250℃ of the steam supply main pipe 5: the high-pressure reducing valve 43 reduces the superheater outlet steam pressure from 3.82MPa and temperature from 450℃ to 1.0MPa, the water spray desuperheater 44 reduces the temperature to 250℃, and the electromagnetic flow control valve 45 adjusts the flow rate range from 100-500t / h according to the network load.

[0040] The burner arrangement for the dual-fuel supply structure is as follows: symmetrically distributed around the boiler furnace 12, with 5 sets of pulverized coal burners 71 (model PM-200) located in the lower middle part of the furnace, and 4 natural gas burners 72 (model TG-150) located between the pulverized coal burners; fuel delivery: the pulverized coal burners 71 are connected to the pulverized coal silo 73 (100m³) via a pulverized coal conveying pipeline 74 (diameter DN200). 3 The connection includes a pulverized coal conveying fan (model 9-19) on the pipeline; the natural gas burner 72 is connected to the municipal pipeline network via a natural gas pipeline 76 with a diameter of DN150, and a pressure regulating valve group 75 (model RTZ-31) is installed on the pipeline to stabilize the pressure to 0.1MPa; safety control: both types of burners are equipped with an ignition device (model DDQ-10) and a flame detector (model UV-200). When the flame detector detects flameout, it immediately feeds back to the central control system 6, and the system cuts off the corresponding fuel pipeline to prevent deflagration.

[0041] Connection of the boiler forced water circulation auxiliary pipeline 8: One end is connected to the downcomer header 13 of the boiler body 1 through a flange, and the other end is connected to the riser header 14 to form a circulation loop; Pipeline components: A variable frequency circulation pump 81, model ISG-150, and a one-way check valve 82, model H44H-16, are installed on the pipeline; Adjustment logic: The central control system 6 collects the temperature of the downcomer header 13 and the riser header 14 through the PT100 temperature sensor and calculates the temperature difference: When the temperature difference is >8℃, the speed of the variable frequency pump is increased to a maximum of 2900r / min; when the temperature difference is <3℃, the speed is reduced to a minimum of 1000r / min to maintain stable water circulation.

[0042] 4. Sealed isolation baffle 9 installation location: at the inlet of the high-pressure cylinder of turbine 2, fixed to the inlet flange by bolts; drive and interlock: the baffle is controlled by a hydraulic drive mechanism 91, model YQ-50, which is connected to the turbine interlock protection system 92 (integrated into the central control system); working logic: after the turbine 2 shutdown signal is triggered, the interlock protection system 92 immediately instructs the hydraulic drive mechanism 91 to act, closing the baffle within 10 seconds to block steam from entering the high-pressure cylinder; before startup, the system confirms that the baffle is fully open before allowing steam to enter.

[0043] The core components of the flue gas waste heat recovery assembly 10 include a finned heat exchanger 101 (model BR0.8-1.0) and a bag filter 102 (model MC-96), both installed in the boiler tail flue 15. Flow path connection: the cold-side inlet 1011 of the heat exchanger connects to the city heating return water header 16, and the cold-side outlet 1012 connects to the desuperheating section 46 of the independent heating main steam pipeline 4. The bag filter 102 is installed before the hot-side inlet 1013, with an online cleaning cycle set to 2 hours to prevent dust from clogging the heat exchanger fins. Water temperature regulation: a water temperature regulating tank 103 (e.g., 5m³ volume) is connected in series between the finned heat exchanger 101 and the return water header 16. 3 The tank is equipped with a spiral stirring blade 1031 (material 316L), a temperature sensor 1032, a K-type thermocouple, and an electric regulating valve 1033 (model ZDLP-65) linked to the temperature sensor 1032: the valve is opened wide when the outlet water temperature is <60℃ and closed narrowly when it is >80℃ to ensure stable steam temperature after mixing.

[0044] Steam buffer tank 17 installation location: After the electromagnetic flow control valve 45 of the independent heating main steam pipeline 4, it is connected via a flange; Accessory configuration: Pressure transmitter 171, model MPM480, is installed at the top, and automatic drain valve 172, model Z44H-16, is installed at the bottom; Pressure control: The pressure transmitter 171 feeds back the tank pressure to the central control system 6 in real time. When the pressure fluctuation exceeds the ±0.05MPa set value of 1.0MPa, the system automatically adjusts the opening of the electromagnetic flow control valve 45: the valve is closed when the pressure is >1.05MPa, and the valve is opened when the pressure is <0.95MPa; The automatic drain valve 172 drains the condensate in the tank once a day at a set time.

[0045] Boiler emergency water supply unit: includes a large-capacity water storage tank 181 (50m³). 3 ), High-lift water supply pump 182, model CDL-80, and shut-off valve 185, model J41H-16; Connection relationship: Water storage tank 181 is connected to boiler drum 19 through water supply pipeline 184, pipe diameter DN100. Water supply pump 182 and shut-off valve 185 are installed in sequence on the water supply pipeline; Interlock logic: Water supply pump 182 is interlocked with boiler drum water level gauge 191, model UHZ-58 / C: When the water level is <-50mm (lower limit set), the water supply pump automatically starts and the shut-off valve opens; when the water level is >+50mm (upper limit set), the water supply pump stops and the shut-off valve closes.

[0046] Sensor arrangement of the three-dimensional temperature monitoring network: 12 high-temperature resistant S-shaped thermocouples are installed on the inner wall of furnace 12, arranged in 3 layers along the height: 4 thermocouples 1m from the bottom in the lower layer, 4 thermocouples 3m from the bottom in the middle layer, and 4 thermocouples 5m from the bottom in the upper layer, evenly covering the cross-section of the furnace; Data application: Thermocouple signals are connected to the central control system 6, and the system draws a real-time furnace temperature field distribution map. When the temperature is >1200℃, the system automatically reduces the fuel supply to the burners in the corresponding area to avoid local overheating.

[0047] The hydraulic clutch mechanism is installed on the rigid coupling 22 between the turbine 2 and the generator 3. Its components include a ring hydraulic cylinder 231 (model YHG1), a position sensor 233 (model LVT-200), and a hydraulic station 235 (model YB-A10). The working logic is as follows: the ring hydraulic cylinder 231 is connected to the hydraulic station 235 via an oil pipe 234 (DN20 diameter). The position sensor 233 detects the piston position of the hydraulic cylinder. Separation: The central control system 6 instructs the hydraulic station to supply oil, causing the piston to push the friction plate assembly to separate, completing the separation of the turbine and generator within 5 seconds. Engagement: The hydraulic station returns oil, the friction plate assembly resets, and after the position sensor provides a engagement signal, the unit can be started.

[0048] Taking steam turbine shutdown as an example, the core function implementation process is as follows.

[0049] When turbine 2 triggers a shutdown signal, isolation baffle 9 closes, blocking steam from entering the high-pressure cylinder; the central control system 6 switches the boiler operating mode: it starts the electric shut-off valve 42 of the independent heating main steam pipeline 4, adjusts the high-pressure reducing valve 43 and the water spray desuperheater 44, and stabilizes the steam parameters to the heating requirements; if the pulverized coal supply is interrupted, the system automatically switches to the natural gas burner 72 to maintain the boiler load; the variable frequency circulating pump 81 automatically adjusts its speed according to the temperature difference between the downcomer and the riser to ensure water circulation; the flue gas waste heat recovery component 10 continuously recovers the waste heat from the tail flue, heats the return water, and then flows it into the steam pipeline; the steam buffer tank 17 stabilizes the steam supply pressure in real time, and automatically adjusts the flow valve when the pressure fluctuation exceeds the limit; the steam drum water level gauge 191 monitors the water level, and the emergency water replenishment unit automatically starts when it is lower than the set value; the three-dimensional temperature monitoring network provides real-time feedback on the furnace temperature to optimize the combustion state; during maintenance, the hydraulic clutch mechanism quickly separates the turbine and the generator, shortening the maintenance time. This embodiment achieves continuous boiler operation and uninterrupted heating when the steam turbine is shut down through the coordinated work of various structures, while ensuring the safe, energy-saving and efficient operation of the unit.

[0050] Finally, it should be noted that this utility model is not limited to the above embodiments, and many variations are possible. All variations that can be directly derived or conceived by those skilled in the art from the disclosure of this utility model should be considered within the protection scope of this utility model.

Claims

1. A heating unit that ensures uninterrupted heating even during shutdowns, comprising a boiler body (1), a steam turbine (2), and a generator (3), characterized in that: An independent heating main steam pipeline (4) is also provided. One end of the independent heating main steam pipeline (4) is directly connected to the superheater outlet (11) of the boiler body (1), and the other end is connected to the steam supply main pipe (5) of the urban heating network through the steam distribution drum (41). An electric shut-off valve (42), a high-pressure reducing valve (43), a water spray desuperheater (44) and an electromagnetic flow control valve (45) are installed in series on the independent heating main steam pipeline (4). All valves are connected to the central control system (6) of the unit.

2. A heating unit that ensures uninterrupted heating supply during shutdowns, as described in claim 1, is characterized in that: The burner area of ​​the boiler body (1) is equipped with a dual-mode fuel supply structure, which includes 5 sets of pulverized coal burners (71) and 4 natural gas burners (72) symmetrically distributed around the furnace (12). The pulverized coal burners (71) are connected to a pulverized coal conveying pipeline (74) with a pulverized coal bin (73), and the natural gas burners (72) are connected to a natural gas pipeline (76) with a pressure regulating valve group (75).

3. A heating unit that ensures uninterrupted heating supply during shutdowns, as described in claim 1 or 2, characterized in that: It also includes a boiler forced water circulation auxiliary pipeline (8), one end of which is connected to the downcomer header (13) of the boiler body (1) and the other end is connected to the riser header (14). A variable frequency circulating pump (81) and a one-way check valve (82) are installed on the pipeline.

4. A heating unit that ensures uninterrupted heating supply during shutdowns, as described in claim 1, is characterized in that: The high-pressure cylinder inlet of the steam turbine (2) is equipped with a sealed isolation baffle (9).

5. A heating unit that ensures uninterrupted heating supply during shutdowns, as described in claim 1, is characterized in that: It is also equipped with a flue gas waste heat deep recovery component (10), which includes a finned heat exchanger (101) installed in the flue gas duct (15) at the tail end of the boiler. The cold side inlet (1011) of the heat exchanger is connected to the return water header (16) of the urban heating network, and the cold side outlet (1012) merges with the de-cooling section (46) of the independent heating main steam pipeline (4). A bag filter (102) that can be cleaned online is installed in front of the hot side inlet (1013) of the heat exchanger.

6. A heating unit that ensures uninterrupted heating supply during shutdowns, as described in claim 5, is characterized in that: A water temperature regulating tank (103) is connected in series on the pipeline between the finned heat exchanger (101) and the return water header (16). The regulating tank is equipped with a spiral stirring blade (1031) and a temperature sensor (1032). The temperature sensor (1032) is linked with an electric regulating valve (1033) to adjust the amount of return water entering the heat exchanger according to the outlet water temperature of the heat exchanger.

7. A heating unit that ensures uninterrupted heating supply during shutdowns, as described in claim 1, characterized in that: A steam buffer tank (17) is installed after the electromagnetic flow control valve (45) of the independent heating main steam pipeline (4). A pressure transmitter (171) is installed on the top of the buffer tank, and an automatic drain valve (172) is installed at the bottom. The pressure transmitter (171) collects the pressure inside the tank in real time and feeds it back to the central control system (6).

8. A heating unit that ensures uninterrupted heating supply during shutdowns, as described in claim 7, characterized in that: It also includes a boiler emergency water supply unit, which includes a large-capacity water storage tank (181) and a high-lift water supply pump (182). The water storage tank (181) is connected to the boiler drum through a water supply pipeline (184). The high-lift water supply pump (182) and a shut-off valve (185) are installed sequentially on the water supply pipeline (184). The high-lift water supply pump (182) is interlocked with the water level gauge in the boiler drum. When the water level is lower than the set value, water supply is automatically started.

9. A heating unit that ensures uninterrupted heating supply during shutdowns, as described in claim 2, characterized in that: The boiler body (1) has a three-dimensional temperature monitoring network arranged on the inner wall of the furnace (12). The monitoring network consists of 12 high-temperature thermocouples. The thermocouples are evenly distributed in three layers along the height of the furnace (12). All thermocouple signals are connected to the central control system (6) of the unit.

10. A heating unit that ensures uninterrupted heating supply during shutdowns, as described in claim 1, characterized in that: A hydraulic clutch mechanism is installed on the rigid coupling (22) between the steam turbine (2) and the generator (3). The hydraulic clutch mechanism includes an annular hydraulic cylinder (231) and a position sensor (233). The annular hydraulic cylinder (231) is connected to the hydraulic station (235) through an oil pipe (234). The position sensor (233) is used to detect the clutch status and transmit the signal to the central control system (6) of the unit, so as to realize the rapid separation or engagement of the steam turbine (2) and the generator (3).

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