Energy-saving heat tracing system
By designing an energy-saving heating system with steam conveying and temperature reduction and pressure reduction technology in the boiler flue gas system, the problems of high energy consumption and safety hazards of traditional heating systems are solved, and a safe, stable and adjustable heating effect is achieved.
Patent Information
- Application Number
- CN202420711880.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-08
- Publication Date
- 2025-03-07
- Estimated Expiration
- 2034-04-08
AI Technical Summary
Traditional heat tracing systems have problems such as high energy consumption, easy to cause safety hazards of fires and electric shocks, and difficult to adjust temperature in boiler flue gas systems, which has led to the threat of stable operation of the equipment.
An energy-saving heating system is designed, using a steam conveying unit, a equipment heating unit and a hydrophobic unit, which is heat-tracing through the steam engine and steam pipe steam, and a temperature reduction reducer and PID control algorithm are used to adjust the temperature to ensure the system is safe, stable and adjustable.
It realizes safe, stable, adjustable temperature and energy-saving operation of the heat tracing system, reduces energy consumption, and improves the safety and reliability of the equipment.
Smart Images
Figure CN222577955U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to an energy-saving heating system and belongs to the technical field of boiler equipment. Background Art
[0002] The heating system of ash hopper, scraper, bucket elevator, ash bin, screw conveyor, caustic soda tank and other devices plays an important role in the stable operation of the boiler flue gas system. Failure of the heating system will directly lead to problems such as ash accumulation in the ash hopper and fly ash compaction. In severe cases, it may even lead to equipment collapse and boiler shutdown. Traditional heating devices such as ash hopper, scraper, bucket elevator, ash bin, screw conveyor, caustic soda tank generally use resistance wire to heat up to achieve equipment insulation. This method has the disadvantages of high energy consumption, easy to cause fire and electric shock safety hazards, and difficulty in adjusting temperature.
[0003] Therefore, designing a safe, stable, and energy-saving heating system with adjustable heating temperature is of great significance to the long-term stable operation of the boiler flue gas system. Utility Model Content
[0004] The technical problem to be solved by the utility model is: how to realize safe, stable, adjustable heating temperature and energy-saving operation of heating systems of devices such as ash hoppers, scrapers, bucket elevators, ash bins, and screw conveyors.
[0005] In order to solve the above technical problems, the technical solution of the utility model is to provide an energy-saving heating system, which includes a steam delivery unit, an equipment heating unit, and a drain unit. The steam delivery unit is used to deliver steam from steam turbine extraction and main steam to the equipment heating unit, the equipment heating unit is used to provide heating for corresponding equipment, and the drain unit is used to recycle the steam condensate after heating.
[0006] Preferably, the steam transported by the steam transport unit comes from steam turbine extraction steam, main steam or a combination of the two.
[0007] More preferably, the steam transported by the steam transport unit comes from steam turbine extraction steam and main steam, the steam supply volume percentages of steam turbine extraction steam and main steam are 20-100% and 0-80% respectively, and the steam supply pressures of steam turbine extraction steam and main steam are 0.5-2.0MPa and 3.5-6.5MPa respectively.
[0008] Preferably, the steam delivery unit is provided with a steam trap for draining accumulated water during start-up and shutdown processes, which is arranged at each low point of the system.
[0009] Preferably, the steam delivery unit and the equipment heating unit are provided with a temperature reducer and pressure reducer for reducing the temperature and pressure of the steam turbine extraction steam and the main steam. The steam parameters of the heating main pipe can be adjusted according to the heating temperature requirements to achieve the purpose of controlling the heating temperature. First, the temperature sensor measures the actual temperature of the steam; then, the actual temperature is compared with the set temperature to calculate the deviation value; then the control quantity is calculated according to the deviation value and the control algorithm; the actuator drives the regulating valve to operate according to the control quantity to adjust the flow rate of the cooling water; finally, the temperature change is monitored in real time through the feedback link to form a closed-loop control. The control algorithm and logic usually adopt the PID (proportional-integral-differential) control algorithm, calculate the control quantity according to the temperature deviation, and eliminate static errors and predict future trends through integral and differential terms, so as to achieve the purpose of dynamically tracking the required heating temperature.
[0010] Preferably, the steam delivery unit needs to be provided with an expansion bend, a fixed bracket and a sliding bracket according to actual conditions to ensure that the steam pipeline expands in the designed direction and prevent the pipeline from being torn.
[0011] Preferably, the equipment heating unit includes a heating pipe for conveying steam to each device for heating. The steam pipes where the devices are located are arranged in parallel. Each heating pipe is provided with an air intake main valve and a drain main valve to ensure the independence of each heating device and facilitate equipment inspection and maintenance. Each drain unit is independent of each other to facilitate inspection and maintenance. A temperature and pressure reducer is provided upstream of each device and a temperature measuring element is provided downstream. Each device is provided with a separate temperature and pressure reducer or different devices share a temperature and pressure reducer. The equipment heating unit increases fins according to the heat exchange requirements. If the heat exchange amount is large, the fins can be appropriately increased.
[0012] More preferably, the shapes of the heat tracing pipes at different devices are adjusted according to the shapes of the outer surfaces of the devices.
[0013] Furthermore, when the equipment is an ash silo, the heating pipe there is a coil; when the equipment is a scraper conveyor or a bucket elevator, the heating pipe there is a serpentine pipe.
[0014] Furthermore, when the equipment is a scraper conveyor or a bucket elevator, a serpentine tube is provided on each side of the equipment, and the serpentine tubes on both sides are connected in parallel, that is, the serpentine tubes are independent of each other, thereby ensuring sufficient heat exchange of each unit.
[0015] Preferably, the drain unit includes a drain main pipe, which is connected to the drain main pipe in the factory area through a main drain valve or to the ditch through an emergency drain valve. The main drain valve and the emergency drain valve are interlocked. When the main drain valve is closed, the emergency drain valve automatically opens to ensure smooth drainage and system safety.
[0016] The utility model adopts steam extraction from steam turbine and steam from steam main pipe to heat ash hopper, scraper, bucket elevator, caustic soda tank and other equipment, so as to realize safe, stable, adjustable heating temperature and energy-saving operation of the heating system of ash hopper, scraper, bucket elevator, caustic soda tank and other equipment.
[0017] The utility model has the following beneficial effects:
[0018] 1. The utility model gives priority to using steam turbine extraction, and using steam that has done work for heating can achieve cascade utilization of energy and improve energy utilization efficiency. If the steam turbine extraction volume is insufficient, the steam from the steam main pipe can be appropriately used for heating after temperature and pressure reduction.
[0019] 2. The utility model has an adjustable usage ratio of steam extraction from the steam turbine and steam from the steam main pipe, and the usage of the two can be adjusted in time according to the usage conditions.
[0020] 3. The utility model can adjust the parameters of the heating steam after the temperature reduction and pressure reduction device in real time according to the needs of the heating users to ensure the heating effect.
[0021] 4. The utility model can adjust the form of the heating pipeline according to the outer surface of the equipment and has strong adaptability.
[0022] 5. The utility model can isolate part of the heating units according to the needs without affecting the normal operation of other heating units, and is convenient for maintenance and highly flexible.
[0023] 6. The utility model is provided with emergency draining, and the normal draining and the emergency draining are interlocked. When the drain main pipe fails, the emergency draining is automatically switched, and the safety is high. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 A schematic diagram of the energy-saving heating system provided by the utility model;
[0025] Figure 2 This is the steam side plan layout (taking four incineration lines as an example);
[0026] Figure 3 This is the water side plan layout (taking four incineration lines as an example);
[0027] Figure 4 This is a top view of the scraper conveyor heating pipe;
[0028] Figure 5 It is the side view of the heating pipe of the scraper conveyor;
[0029] Figure 6 This is a partial enlarged view of the scraper conveyor heating pipe;
[0030] Figure 7 It is a side view of the bucket elevator heating pipe;
[0031] Figure 8 for Figure 7 A partial enlarged view of part I;
[0032] Fig. 9 It is a top view of the heating pipe of the screw conveyor;
[0033] Fig.10 It is a side view of the heating pipe of the screw conveyor;
[0034] Fig.11 This is the main view of the ash hopper heating pipe;
[0035] Fig.12 for Fig.11 A top view of
[0036] Fig.13 This is a partial enlarged view of the ash hopper heating pipe;
[0037] Fig.14 for Fig.13 Side view of. DETAILED DESCRIPTION
[0038] In order to make the present invention more clearly understood, preferred embodiments are described in detail below with reference to the accompanying drawings.
[0039] Example
[0040] The utility model provides an energy-saving heating system, such as Figure 1 As shown, it includes a steam delivery unit, an equipment heating unit, and a drain unit.
[0041] The steam delivery unit includes two steam inlet pipelines, one of which is connected in sequence to the steam turbine extraction main pipe 101, the temperature reducing and pressure reducing device 1 102, and the steam turbine extraction steam inlet main valve 103, and the other is connected in sequence to the main steam main pipe 104, the temperature reducing and pressure reducing device 2 105, and the steam main pipe steam inlet main valve 106. Both steam inlet pipelines are connected to the steam inlet main pipe of the equipment heating unit.
[0042] The equipment heating unit includes multiple heating pipes connected in parallel to the steam inlet main pipe. Each heating pipe corresponds to one equipment. Figure 1Only six devices are listed, which can be adjusted according to production needs. The six devices in this embodiment are reaction tower, dust collector, public ash conveyor, bucket elevator, ash bin, and caustic soda tank. The corresponding heating pipes are reaction tower heating pipe, dust collector heating pipe, public ash conveyor heating pipe, bucket elevator heating pipe, ash bin heating pipe, and caustic soda tank heating pipe. The reaction tower heating pipe is provided with a reaction tower heating steam inlet main valve 201, a temperature reducing and pressure reducing device 3 202, a reaction tower steam point 203, and a temperature measuring element 1 204. The dust collector heating pipe is provided with a dust collector heating steam inlet main valve 301, a temperature reducing and pressure reducing device 4 302, a dust collector steam point 303, and a temperature measuring element 2 304. The public ash conveyor The heating pipe is provided with a public ash conveyor steam inlet main valve 401, a temperature reducing and pressure reducing device 5 402, a public ash conveyor steam point 403, and a temperature measuring element 3 404 in sequence; the bucket elevator heating pipe is provided with a bucket elevator steam inlet main valve 501, a temperature reducing and pressure reducing device 6 502, a bucket elevator steam point 503, and a temperature measuring element 4 504 in sequence; the ash silo heating pipe is provided with an ash silo steam inlet main valve 601, a temperature reducing and pressure reducing device 702, an ash silo steam point 603, and a temperature measuring element 5 604 in sequence; the caustic soda tank body heating pipe is provided with a caustic soda room steam inlet main valve 701, a temperature reducing and pressure reducing device 8 702, a caustic soda room steam point 703, and a temperature measuring element 6 704 in sequence.
[0043] The drain unit includes a drain main pipe connected to each heating pipe of the equipment heating unit, and the output end of each heating pipe is connected to the drain main pipe through a drain main valve. In this embodiment, the reaction tower heating pipe, the dust collector heating pipe, the public ash conveyor heating pipe, the bucket elevator heating pipe, the ash bin heating pipe, and the caustic soda tank heating pipe are respectively provided with a reaction tower drain main valve 205, a dust collector drain main valve 305, a public ash conveyor drain main valve 405, a bucket elevator drain main valve 505, an ash bin drain main valve 605, and a caustic soda tank drain main valve 705. The drain main pipe is further divided into two routes, one route is connected to the drain main pipe 802 of the plant area through the main drain valve 801, and the other route is connected to the ditch 902 through the emergency drain valve 901.
[0044] like Figure 2As shown in the figure, the system gives priority to steam turbine extraction, and according to the heating temperature requirement, the steam turbine is extracted and desuperheated and decompressed before being input into the steam delivery unit, and then into the subsequent equipment heating unit. When the steam turbine extraction volume is insufficient, part of the main steam is used to ensure the subsequent heating effect. Temperature measuring elements are set on the outer surface of the scraper of the heating ash hopper and the public ash conveyor. First, the temperature sensor measures the actual temperature of the steam; then, the actual temperature is compared with the set temperature to calculate the deviation value; then the control quantity is calculated based on the deviation value and the control algorithm; the actuator drives the regulating valve to act according to the control quantity and adjusts the flow of the desuperheating water; finally, the temperature change is monitored in real time through the feedback link to form a closed-loop control. The control algorithm and logic usually adopt the PID (proportional-integral-differential) control algorithm, calculate the control quantity based on the temperature deviation, and eliminate the static error and predict the future trend through the integral and differential terms, so as to achieve the purpose of dynamically tracking the required heating temperature.
[0045] To ensure safety, expansion bends, fixed brackets and sliding brackets are appropriately set according to the length and direction of the pipeline to ensure that the pipeline expands in the designed direction and prevent the pipeline from cracking. The steam transmission unit is equipped with drain valves at low points in various parts of the system to ensure that the accumulated water in the system can be discharged in time to ensure the safety of the system. All pipelines are equipped with corresponding insulation layers and outer protective plates according to design specifications to reduce heat loss.
[0046] The steam from the steam transport unit enters the hopper-shaped heating coils of the reaction tower, dust collector, ash bin, etc. The heating pipes spirally rise according to the facade of the ash hopper. The heating pipes are fixed to the outer surface of the ash hopper with pipe clamps. A pipe clamp is set every half a meter to ensure that the heating pipes are in full contact with the outer surface of the heating equipment. Fins can be arranged on the heat exchange pipes according to the heat exchange requirements to ensure the heat exchange requirements. A heating steam main pipe is set on the outside of the scraper, and a finished serpentine heating pipe is set on the side of each scraper unit. Each serpentine heating pipe is connected to the heating steam main pipe. Fins can be arranged on the heat exchange pipes according to the heat exchange requirements to ensure the heat exchange requirements. The reaction tower, dust collector, and scraper heating main pipe of each production line are equipped with main valves to facilitate equipment inspection and maintenance. All pipelines are equipped with corresponding insulation layers and outer protective plates according to design specifications to reduce heat loss.
[0047] like Figure 3As shown, the ends of each heat tracing pipe are connected to the main drain pipe of the drain unit, and a main drain valve is set before each drain enters the main drain pipe to ensure that the heat tracing and draining of each device are relatively independent, which is convenient for equipment inspection and maintenance. To ensure safety, expansion bends, fixed brackets and sliding brackets are properly set according to the length and direction of the drain pipe to ensure that the pipeline expands in the designed direction and prevent the pipeline from cracking. The main drain pipe valve is always open, and the drain flows into the main drain pipe 802 in the plant area. A bypass to the ditch 902 in the plant area is set before the main drain pipe 802 in the plant area, and an emergency drain valve 901 is set in the middle. The main drain valve 801 and the emergency drain valve 901 are interlocked. When the main drain valve 801 is closed, the emergency drain valve 901 automatically opens to ensure smooth draining and ensure system safety.
[0048] The shape of the heat tracing pipes at different equipment is adjusted according to the outer surface shape of the equipment. Figure 11-12 The coil is shown, and a pipe clamp 206 (such as Figure 13-14 The heat tracing pipes at the scraper, bucket elevator and screw conveyor of the public ash conveyor are serpentine pipes, with one serpentine pipe on each side, and the serpentine pipes on both sides are connected in parallel. Figure 4-6 As shown, the arrangement of the scraper bucket elevator heat tracing pipe 210 is as follows Figure 7-8 As shown, the setting of the screw conveyor heating pipe 212 is as follows Figure 9-10 When installing, all heating pipes are fixed to the shell of the corresponding equipment by spot welding, and the welding interval is preferably 300mm.
Claims
1. An energy-saving heating system, characterized in that: It includes a steam delivery unit, an equipment heating unit and a drain unit. The steam delivery unit is used to deliver the steam from the steam turbine extraction steam and the main steam to the equipment heating unit. The equipment heating unit is used to provide heating for the corresponding equipment. The drain unit is used to recycle the condensed water of the steam after heating.
2. The energy-saving heating system according to claim 1, characterized in that: The steam transported by the steam transport unit comes from steam turbine extraction steam, main steam or a combination of the two.
3. The energy-saving heating system according to claim 2, characterized in that: The steam transported by the steam transport unit comes from turbine extraction steam and main steam. The steam supply volume percentages of turbine extraction steam and main steam are 20-100% and 0-80% respectively. The steam supply pressures of turbine extraction steam and main steam are 0.5-2.0MPa and 3.5-6.5MPa respectively.
4. The energy-saving heating system according to claim 1, characterized in that: The steam delivery unit is provided with a steam trap for draining the accumulated water during the start-up and shutdown processes, which is arranged at each low point of the system.
5. The energy-saving heating system according to claim 1, characterized in that: The steam delivery unit and the equipment heating unit are provided with a temperature reducer and pressure reducer for reducing the temperature and pressure of the steam turbine extraction steam and the main steam.
6. The energy-saving heating system according to claim 1, characterized in that: The equipment heating unit includes a heating pipe for conveying steam to each device for heating. The steam pipelines where the devices are located are arranged in parallel. Each heating pipe is provided with an air intake main valve and a drain main valve. Each drain unit is independent of each other for easy inspection and maintenance. A temperature and pressure reducing device is provided upstream of each device and a temperature measuring element is provided downstream. Each device is provided with a separate temperature and pressure reducing device or different devices share a temperature and pressure reducing device. The equipment heating unit is provided with fins according to the heat exchange requirements.
7. The energy-saving heating system according to claim 6, characterized in that: The shape of the heating pipes at different equipment is adjusted according to the outer surface shape of the equipment.
8. The energy-saving heating system according to claim 7, characterized in that: When the equipment is an ash silo, the heating pipe there is a coil; when the equipment is a scraper or a bucket elevator, the heating pipe there is a serpentine pipe.
9. The energy-saving heating system according to claim 8, characterized in that: When the equipment is a scraper conveyor or a bucket elevator, a serpentine pipe is arranged on each side of the equipment, and the serpentine pipes on both sides are connected in parallel.
10. The energy-saving heat tracing system according to claim 1, characterized in that: The drain unit includes a drain main pipe, which is connected to the drain main pipe in the factory area through a main drain valve or to the ditch through an emergency drain valve. The main drain valve and the emergency drain valve are interlocked. When the main drain valve is closed, the emergency drain valve is automatically opened.