Boiler make-up water heating system based on sludge incineration boiler tail gas waste heat utilization

Abstract

The utility model discloses a boiler make-up water heating system based on waste heat utilization of tail gas of a sludge incineration boiler, belongs to the technical field of waste heat recovery, and solves the problem that heat in flue gas is recycled to heat boiler make-up water so as to realize repeated recycling of resources. Comprising a boiler air duct, and a lower mounting frame communicating with the interior of the boiler air duct is fixedly connected to the peripheral wall of the boiler air duct. According to the system, the tail gas of the sludge incineration boiler can be guided to pass through the air pre-heater and the low-temperature coal economizer through the boiler air duct, so that heat in the tail gas of the sludge incineration boiler is recycled, and meanwhile, the flue gas amount of the tail gas of the sludge incineration boiler is large; the low-temperature liquid output from the slag cooler can be heated to the temperature capable of being used in a steam turbine, the actions of outputting the heated liquid and inputting the low-temperature liquid can be autonomously performed according to the change of the temperature, huge heat in tail gas of a sludge incineration boiler is fully utilized, and the resource utilization rate is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of waste heat recovery, in particular to a boiler feed water heating system based on the utilization of waste heat from tail gas of a sludge incineration boiler. Background Art

[0002] The sludge incineration boiler was designed with efficient energy utilization in mind, and the exhaust temperature was set at 160°C to optimize the recovery and utilization of heat energy. However, in actual operation, due to the influence of operating conditions and environmental factors, the exhaust temperature tends to be maintained between 180°C and 200°C, which indicates that the boiler has a high potential for utilizing waste heat from flue gas in actual operation. This temperature range means that there is room for further improvement in the thermal efficiency of the boiler. By taking appropriate technical measures and equipment modifications, this additional heat energy can be effectively recovered, thereby reducing energy waste and improving overall energy utilization efficiency.

[0003] In addition, the flue gas volume of the boiler is considerable, reaching 200,000 standard cubic meters per hour. This data not only demonstrates the boiler's ability to treat sludge, but also highlights the importance of flue gas waste heat recovery. Through the reasonable design and installation of flue gas waste heat recovery, the heat in the flue gas can be converted into useful thermal energy for heating water, generating steam or generating electricity, thereby providing additional energy supply for the factory and reducing energy costs. It also helps to reduce greenhouse gas emissions and achieve environmental protection goals. Therefore, it is necessary to add a device in the air duct of the sludge incineration boiler that can recycle the heat in the flue gas and reuse it in the work of heating the boiler feed water, so as to achieve repeated recycling of resources.

[0004] Therefore, a boiler feed water heating system based on the utilization of waste heat from tail gas of a sludge incineration boiler is proposed to solve or alleviate the above problems. Utility Model Content

[0005] The utility model aims to solve the shortcomings in the prior art and proposes a boiler feed water heating system based on the utilization of waste heat from tail gas of a sludge incineration boiler.

[0006] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0007] A boiler feed water heating system based on the utilization of waste heat from tail gas of a sludge incineration boiler includes a boiler air duct, a lower mounting frame connected to the interior of the boiler air duct is fixedly connected to the outer peripheral wall of the boiler air duct, a low-temperature economizer is fixedly connected in the lower mounting frame, the low-temperature economizer has two paths for connecting to a slag cooler and a steam turbine respectively, a temperature control circuit is arranged in the low-temperature economizer, and the temperature control circuit controls the switching of the two paths.

[0008] Preferably, the low-temperature economizer includes a plurality of heat exchange coils located in a lower mounting frame, the heat exchange coils are connected with an inlet pipe and an outlet pipe located above the heat exchange coils, the inlet pipe and the outlet pipe are respectively connected with an inlet solenoid valve and an outlet solenoid valve, the inlet solenoid valve is used to connect with a slag cooler, the outlet solenoid valve is used to connect with a steam turbine, a plurality of the inlet pipes are commonly connected with an intake solenoid valve, a plurality of the outlet pipes are commonly connected with an exhaust solenoid valve, and the intake solenoid valve and the exhaust solenoid valve are respectively connected with an intake pipe and an exhaust pipe, and the temperature control circuit is coupled with the inlet solenoid valve, the outlet solenoid valve, the intake solenoid valve, and the exhaust solenoid valve.

[0009] Preferably, the low-temperature economizer further comprises a connection frame fixedly connected in the lower installation frame, and the plurality of heat exchange coils are all fixedly connected in the connection frame.

[0010] Preferably, the temperature control circuit includes a temperature sensor fixedly connected in the heat exchange coil, a voltage comparator 1 and a voltage comparator 2 coupled to the temperature sensor, and a controller coupled to the two, the controller is coupled to the inlet solenoid valve, the outlet solenoid valve, the air intake solenoid valve, and the exhaust solenoid valve, and the threshold values ​​of the voltage comparator 1 and the voltage comparator 2 are different.

[0011] Preferably, the controller is a 51 series single chip microcomputer.

[0012] Preferably, it also includes an air inlet connected to the top of the boiler air duct, and an air outlet connected to the lower end of the boiler air duct and located on the outer peripheral wall, wherein the air outlet is used to connect to the bag dust collector.

[0013] Preferably, it also includes an upper mounting frame fixedly connected to the outer peripheral wall of the boiler air duct and communicated with the interior thereof, an air preheater is fixedly connected to the upper mounting frame, and the air preheater is used to be connected with the boiler.

[0014] The utility model has the following beneficial effects:

[0015] The design of the utility model utilizes the exhaust gas emitted by the sludge incineration boiler. By guiding the exhaust gas to the boiler air duct, it passes through the air preheater and the low-temperature economizer in sequence, thereby achieving effective recovery and reuse of the heat energy contained in the exhaust gas. This design not only improves the energy utilization efficiency, but also helps to reduce the operating cost of the boiler, while also reducing thermal pollution to the environment.

[0016] Since the amount of exhaust gas generated by the sludge incineration boiler is very large, the heat carried by the exhaust gas when passing through the above-mentioned structure is enough to heat the low-temperature liquid discharged from the slag cooler to a suitable temperature for use by the steam turbine. This treatment process not only improves the calorific value of the low-temperature liquid, but also provides a stable source of heat for the steam turbine, thereby improving the thermal efficiency of the entire energy system.

[0017] In addition, the utility model also has a control function, which can autonomously adjust the output of heated liquid and the input of low-temperature liquid according to the temperature data monitored in real time by the temperature sensor. This temperature control mechanism ensures the continuity and stability of the heat recovery process and avoids energy waste caused by temperature fluctuations.

[0018] Through this efficient exhaust gas heat recovery technology, the utility model not only improves the energy utilization efficiency of the sludge incineration boiler, but also helps to achieve sustainable development of energy. The application of this technology has important practical significance for promoting energy conservation and emission reduction, protecting the environment, and promoting the green transformation of industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the utility model;

[0020] Figure 2 for Figure 1 The enlarged view of point A in the middle;

[0021] Figure 3 It is a structural block diagram of the temperature control circuit in the utility model.

[0022] 1. Boiler air duct; 2. Air inlet; 3. Air outlet; 4. Upper mounting frame; 5. Lower mounting frame; 6. Connection frame; 7. Heat exchange coil; 8. Exhaust solenoid valve; 9. Exhaust pipe; 10. Outlet solenoid valve; 11. Inlet solenoid valve; 12. Inlet pipe; 13. Inlet solenoid valve; 14. Controller; 15. Voltage comparator 1; 16. Voltage comparator 2; 17. Temperature sensor. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0024] Boiler feed water heating system based on the utilization of waste heat from tail gas of sludge incineration boiler, such as Figure 1 As shown, it includes a boiler air duct 1, an air inlet 2 connected to the top of the boiler air duct 1, an air outlet 3 connected to the lower end of the boiler air duct 1 and located on the outer peripheral wall, and an upper mounting frame 4 fixedly connected to the outer peripheral wall of the boiler air duct 1 and connected to the interior thereof, an air preheater is fixedly connected in the upper mounting frame 4, the air preheater is used to be connected to the boiler, and the air outlet 3 is used to be connected to a bag dust collector.

[0025] A lower mounting frame 5 connected to the interior of the boiler duct 1 is fixedly connected to the outer peripheral wall thereof, and a low-temperature economizer is fixedly connected inside the lower mounting frame 5. The low-temperature economizer has two paths for connecting the slag cooler and the steam turbine respectively. A temperature control circuit is provided inside the low-temperature economizer, and the temperature control circuit controls the switching of the two paths.

[0026] like Figure 2 As shown, the low-temperature economizer includes a connection frame 6 fixedly connected in the lower installation frame 5, and a plurality of heat exchange coils 7 fixedly connected in the connection frame 6. The heat exchange coil 7 is connected with an inlet pipe and an outlet pipe located above it. The inlet pipe and the outlet pipe are respectively connected with an inlet solenoid valve 13 and an outlet solenoid valve 10. The inlet solenoid valve 13 is used to communicate with the slag cooler, and the outlet solenoid valve 10 is used to communicate with the steam turbine. The plurality of inlet pipes are commonly connected with an intake solenoid valve 11, and the plurality of outlet pipes are commonly connected with an exhaust solenoid valve 8. The intake solenoid valve 11 and the exhaust solenoid valve 8 are respectively connected with an intake pipe 12 and an exhaust pipe 9. The temperature control circuit is coupled with the inlet solenoid valve 13, the outlet solenoid valve 10, the intake solenoid valve 11, and the exhaust solenoid valve 8. Figure 3 As shown, the temperature control circuit includes a temperature sensor 17 fixedly connected to the heat exchange coil 7, a voltage comparator 15 and a voltage comparator 2 16 coupled to the temperature sensor 17, and a controller 14 coupled to the two and being a 51 series single chip microcomputer. The controller 14 is coupled to the inlet solenoid valve 13, the outlet solenoid valve 10, the intake solenoid valve 11, and the exhaust solenoid valve 8, and the threshold values ​​of the voltage comparator 15 and the voltage comparator 2 16 are different.

[0027] During the actual operation of the utility model, the exhaust gas of the sludge incineration boiler can enter the boiler air duct 1 through the air inlet 2 and leave through the air outlet 3. In the process of the exhaust gas of the sludge incineration boiler entering from the air inlet 2 and leaving from the air outlet 3, the exhaust gas of the sludge incineration boiler will exchange heat with the air preheater. The air preheater connected to the boiler can exchange heat with a part of the heat in the exhaust gas of the sludge incineration boiler, thereby transferring it to the boiler, and recycling the exhaust gas of the sludge incineration boiler, thereby improving the waste heat utilization rate of the exhaust gas of the sludge incineration boiler.

[0028] Then, the tail gas of the sludge incineration boiler will also pass through the low-temperature economizer in the lower mounting frame 5 for heat exchange. When the low-temperature economizer is performing heat exchange, the tail gas of the sludge incineration boiler mainly contacts with a plurality of heat exchange coils 7, thereby completing the heat exchange action.

[0029] When the tail gas of the sludge incineration boiler heats the water in the heat exchange coil 7 to the required temperature, the temperature sensor 17 can detect the temperature therein and send a temperature signal to the voltage comparator 1 15 and the voltage comparator 2 16. Since the threshold values ​​set by the voltage comparator 1 15 and the voltage comparator 2 16 are different, that is, the voltage values ​​compared by the two are different, the temperature sensor 17 can only meet one of the threshold values ​​at the corresponding temperature. When the heating temperature reaches the standard, the voltage comparator 1 15 compares the temperature signal to the standard and sends a comparison signal 1 to the controller 14 which is a 51 series single chip microcomputer. The controller The controller 14 will control the intake solenoid valve 11 to open, and the outlet solenoid valve 10 will also open, the inlet solenoid valve 13 and the exhaust solenoid valve 8 will be closed, and the intake pipe 12 is also connected to a one-way valve, which can control the air from the outside to enter the intake pipe 12 and the intake solenoid valve 11 and the intake pipe in one direction. At this time, the steam turbine can extract the high-temperature water in the heat exchange coil 7, and the outside air continues to enter the heat exchange coil 7, so that the high-temperature water in the heat exchange coil 7 will not be mixed with the low-temperature water in the slag cooler, but can be blocked by air to ensure that the high-temperature water in the heat exchange coil 7 all leaves through the outlet pipe.

[0030] A certain period of time after all the high-temperature water has left, the controller 14 will re-control the intake solenoid valve 11 to close, and the outlet solenoid valve 10 will also close, the inlet solenoid valve 13 and the exhaust solenoid valve 8 will open, and the slag cooler will send low-temperature water into the heat exchange coil 7 through the inlet pipe, and the low-temperature water will remove the air in the heat exchange coil 7 through the exhaust solenoid valve 8 and the exhaust pipe 9, ensuring that the heat exchange coil 7 is full of low-temperature water from the slag cooler. Then, when the temperature sensor 17 detects the temperature of the low-temperature water, it will send a temperature signal to the voltage comparator 1 15 and the voltage comparator 2 16. At this time, the temperature signal of the low water temperature meets the threshold set in the voltage comparator 2 16. The voltage comparator 2 16 sends a comparison signal 2 to the controller 14. The controller 14 will control the exhaust solenoid valve 8 to open, and the intake solenoid valve 11, the outlet solenoid valve 10, and the inlet solenoid valve 13 are all closed until the low-temperature water therein is heated to the temperature position of the high-temperature water that meets the requirements of the steam turbine, and then repeat the above actions.

[0031] In this way, from entering the boiler air duct 1 to leaving it, the sludge incineration boiler exhaust gas can exchange heat with multiple structures, thereby fully utilizing the heat therein and applying it to the boiler feed water heating to realize waste heat recovery.

[0032] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A boiler feed water heating system based on utilization of waste heat from tail gas of a sludge incineration boiler, comprising a boiler air duct (1), characterized in that: A lower mounting frame (5) connected to the interior of the boiler duct (1) is fixedly connected to the outer peripheral wall thereof, and a low-temperature economizer is fixedly connected inside the lower mounting frame (5). The low-temperature economizer has two paths for connecting to the slag cooler and the steam turbine respectively. A temperature control circuit is provided inside the low-temperature economizer, and the temperature control circuit controls the switching of the two paths.

2. The boiler feed water heating system based on the utilization of waste heat from tail gas of sludge incineration boiler according to claim 1 is characterized in that: The low-temperature economizer comprises a plurality of heat exchange coils (7) located in a lower mounting frame (5), wherein the heat exchange coils (7) are connected to an inlet pipe and an outlet pipe located above the heat exchange coils (7), wherein the inlet pipe and the outlet pipe are respectively connected to an inlet solenoid valve (13) and an outlet solenoid valve (10), wherein the inlet solenoid valve (13) is used to be connected to a slag cooler, and the outlet solenoid valve (10) is used to be connected to a steam turbine, wherein a plurality of the inlet pipes are commonly connected to an intake solenoid valve (11), and a plurality of the outlet pipes are commonly connected to an exhaust solenoid valve (8), and the intake solenoid valve (11) and the exhaust solenoid valve (8) are respectively connected to an intake pipe (12) and an exhaust pipe (9), and the temperature control circuit is coupled to the inlet solenoid valve (13), the outlet solenoid valve (10), the intake solenoid valve (11), and the exhaust solenoid valve (8).

3. The boiler feed water heating system based on the utilization of waste heat from tail gas of sludge incineration boiler according to claim 2 is characterized in that: The low-temperature economizer also includes a connection frame (6) fixedly connected to the lower installation frame (5), and the plurality of heat exchange coils (7) are all fixedly connected to the connection frame (6).

4. The boiler feed water heating system based on the utilization of waste heat from tail gas of a sludge incineration boiler according to claim 2 is characterized in that: The temperature control circuit comprises a temperature sensor (17) fixedly connected to the heat exchange coil (7), a voltage comparator 1 (15) and a voltage comparator 2 (16) coupled to the temperature sensor (17), and a controller (14) coupled to the two. The controller (14) is coupled to an inlet solenoid valve (13), an outlet solenoid valve (10), an air intake solenoid valve (11), and an exhaust solenoid valve (8), and the threshold values ​​of the voltage comparator 1 (15) and the voltage comparator 2 (16) are different.

5. The boiler feed water heating system based on the utilization of waste heat from tail gas of sludge incineration boiler according to claim 4 is characterized in that: The controller (14) is a 51 series single chip microcomputer.

6. The boiler feed water heating system based on the utilization of waste heat from tail gas of a sludge incineration boiler according to claim 1 is characterized in that: It also includes an air inlet (2) connected to the top of the boiler air duct (1), and an air outlet (3) connected to the lower end of the boiler air duct (1) and located on the outer peripheral wall, wherein the air outlet (3) is used to connect to a bag dust collector.

7. The boiler feed water heating system based on the utilization of waste heat from tail gas of sludge incineration boiler according to claim 1 is characterized in that: It also comprises an upper mounting frame (4) fixedly connected to the outer peripheral wall of the boiler air duct (1) and communicated with the interior thereof, wherein an air preheater is fixedly connected inside the upper mounting frame (4), and the air preheater is used to be communicated with the boiler.

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