Sludge drying system utilizing waste heat of tail flue gas of gas-fired boiler
By designing a sludge drying system that utilizes waste heat from flue gas at the tail end of a gas-fired boiler, and by using an absorption tower and heat pump unit to recover the waste heat from the flue gas, the problem of waste heat from the boiler tail end was solved, achieving efficient sludge drying and energy utilization, reducing the sludge moisture content and improving the boiler thermal efficiency.
Patent Information
- Application Number
- CN202422088589.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-27
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2034-08-27
AI Technical Summary
The waste heat from the flue gas at the tail end of existing boilers is not effectively utilized, resulting in heat energy waste and global warming, and the energy utilization efficiency during the sludge drying process is low.
A sludge drying system utilizing the waste heat from the flue gas at the tail end of a gas-fired boiler was designed. The waste heat from the flue gas is recovered through an absorption tower, a heat pump unit, and a heating network system. Combined with the drying chamber, conveyor belt, and heater in the sludge dryer, the waste heat is utilized efficiently.
Effective recovery and reuse of waste heat from the tail end of gas-fired boilers reduces boiler heat loss and improves boiler thermal efficiency. After sludge drying, the moisture content is reduced to 30%, and the calorific value of dried sludge reaches the level of biomass fuel.
Smart Images
Figure CN223866508U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a sludge drying system that utilizes the waste heat from the tail flue gas of a gas-fired boiler, belonging to the field of waste heat utilization technology for boiler tail flue gas. Background Technology
[0002] Waste heat refers to excess or waste energy that is not utilized in energy utilization equipment under certain economic and technological conditions. Waste heat recovery and utilization is an important way to improve economic efficiency and save fuel.
[0003] In most existing boilers, the flue gas from the tail flue is discharged directly after dust removal. The flue gas discharged from the tail flue is generally at a high temperature, and direct discharge will result in a waste of heat energy and will also contribute to global warming to some extent. Utility Model Content
[0004] The purpose of this invention is to provide a sludge drying system that utilizes the waste heat of flue gas at the tail end of a gas-fired boiler, thereby recovering and reusing the waste heat of flue gas at the tail end of the gas-fired boiler, thereby reducing boiler heat loss, saving energy, improving boiler thermal efficiency, and ensuring complete combustion of fuel to achieve efficient energy utilization.
[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a sludge drying system utilizing the waste heat of flue gas from the tail end of a gas-fired boiler, including a flue gas duct from the tail end of the gas-fired boiler and a sludge dryer. The flue gas duct from the tail end of the gas-fired boiler is connected to an absorption tower, and a heat pump unit is connected to the absorption tower. A booster fan is installed between the flue gas duct from the tail end of the gas-fired boiler and the absorption tower. A heat network system is installed on the heat pump unit, and the heat network system is connected to the sludge dryer and / or the heat pump unit is connected to the sludge dryer.
[0006] The aforementioned sludge drying system utilizing waste heat from the tail flue gas of a gas-fired boiler includes a sludge dryer comprising a slitting machine, a conveyor belt, a fan, and a cooler and heater in a dehumidification chamber. The slitting machine is positioned above the conveyor belt, the cooler is connected to the drying chamber, the heat network system is connected to the heater, the heater is connected to the drying chamber, and the cooler is connected to the heater.
[0007] The aforementioned sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler includes a heat pump unit connected to a heater.
[0008] The aforementioned sludge drying system utilizing the waste heat from the tail flue gas of a gas-fired boiler has a chimney at the top of the absorption tower, which is connected to the tail flue gas duct of the gas-fired boiler.
[0009] The aforementioned sludge drying system utilizing waste heat from the tail flue gas of a gas-fired boiler uses a belt dryer as the sludge dryer.
[0010] The aforementioned sludge drying system that utilizes waste heat from the tail flue gas of a gas-fired boiler has a heat pump unit connected to a steam pipeline.
[0011] The aforementioned sludge drying system utilizing waste heat from the tail flue gas of a gas-fired boiler includes a heating network system comprising a heating network supply water pipe and a heating network return water pipe.
[0012] In the aforementioned sludge drying system utilizing waste heat from the tail flue gas of a gas-fired boiler, the heating network water supply pipe is connected to the heater inlet, and the heating network return water pipe is connected to the heater outlet.
[0013] Compared with existing technologies, this utility model effectively recovers and reuses the waste heat of flue gas at the tail end of gas-fired boilers, thereby reducing boiler flue gas heat loss, saving energy, improving boiler thermal efficiency, and ensuring full combustion of fuel to achieve efficient energy utilization. After low-temperature waste heat drying treatment, the sludge moisture content is reduced to 30%, and the calorific value of the dried sludge can reach the level of biomass fuel. Attached Figure Description
[0014] Figure 1 This is a schematic diagram of the structure of this utility model;
[0015] Figure 2 This is a structural schematic diagram of Embodiment 10 of this utility model;
[0016] Figure 3 This is a schematic diagram of the sludge drying machine in this utility model.
[0017] Attached reference numerals: 1-Gas-fired boiler tail flue gas duct, 2-Sludge dryer, 3-Absorption tower, 4-Heat pump unit, 5-Booster fan, 6-Strip cutter, 7-Conveyor belt, 8-Fan, 9-Cooler, 10-Heater, 11-Chimney, 12-Steam duct, 13-Heating network water supply duct, 14-Heating network return duct.
[0018] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. Detailed Implementation
[0019] Embodiment 1 of this utility model: A sludge drying system utilizing the waste heat of flue gas from the tail end of a gas-fired boiler, including a flue gas duct 1 from the tail end of the gas-fired boiler and a sludge dryer 2. The flue gas duct 1 from the tail end of the gas-fired boiler is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the flue gas duct 1 from the tail end of the gas-fired boiler and the absorption tower 3. A heat network system is installed on the heat pump unit 4, and the heat network system is connected to the sludge dryer 2 and / or the heat pump unit 4 is connected to the sludge dryer 2.
[0020] Embodiment 2 of this utility model: A sludge drying system utilizing the waste heat of flue gas from the tail end of a gas-fired boiler, including a flue gas duct 1 from the tail end of the gas-fired boiler and a sludge dryer 2. The flue gas duct 1 from the tail end of the gas-fired boiler is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the flue gas duct 1 from the tail end of the gas-fired boiler and the absorption tower 3. A heat network system is installed on the heat pump unit 4, and the heat network system is connected to the sludge dryer 2 and / or the heat pump unit 4 is connected to the sludge dryer 2. The sludge dryer 2 includes a strip cutter 6, a conveyor belt 7, and a fan 8 in the drying chamber, and a cooler 9 and a heater 10 in the dehumidification chamber. The strip cutter 6 is placed above the conveyor belt 7. The cooler 9 is connected to the drying chamber. The heat network system is connected to the heater 10. The heater 10 is connected to the drying chamber. The cooler 9 is connected to the heater 10.
[0021] Embodiment 3 of this utility model: A sludge drying system utilizing the waste heat of flue gas from a gas-fired boiler, comprising a flue gas duct 1 from the tail end of the gas-fired boiler and a sludge dryer 2. The flue gas duct 1 is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the flue gas duct 1 and the absorption tower 3. A heat network system is installed on the heat pump unit 4, and the heat network system is connected to the sludge dryer 2 and / or the heat pump unit 4 is connected to the sludge dryer 2. The sludge dryer 2 includes a strip cutter 6, a conveyor belt 7, and a fan 8 in the drying chamber, and a cooler 9 and a heater 10 in the dehumidification chamber. The strip cutter 6 is positioned above the conveyor belt 7. The cooler 9 is connected to the drying chamber. The heat network system is connected to the heater 10, and the heater 10 is connected to the drying chamber. The heat pump unit 4 is connected to the heater 10.
[0022] Embodiment 4 of this utility model: A sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler, comprising a gas-fired boiler tail gas duct 1 and a sludge dryer 2. The gas-fired boiler tail gas duct 1 is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the gas-fired boiler tail gas duct 1 and the absorption tower 3. A heat network system is installed on the heat pump unit 4, and the heat network system is connected to the sludge dryer 2 and / or the heat pump unit 4 is connected to the sludge dryer 2. The sludge dryer 2 includes a strip cutter 6, a conveyor belt 7, a fan 8 in the drying chamber, and a cooler 9 and a heater 10 in the dehumidification chamber. The strip cutter 6 is placed above the conveyor belt 7. The cooler 9 is connected to the drying chamber. The heat network system is connected to the heater 10. The heater 10 is connected to the drying chamber. The heat pump unit 4 is connected to the heater 10. The top of the absorption tower 3 is equipped with a chimney 11, which is connected to the flue gas duct 1 at the tail end of the gas boiler.
[0023] Embodiment 5 of this utility model: A sludge drying system utilizing the waste heat of flue gas from a gas-fired boiler, comprising a flue gas duct 1 from the tail end of the gas-fired boiler, and a sludge dryer 2. The flue gas duct 1 is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the flue gas duct 1 and the absorption tower 3. A heat network system is installed on the heat pump unit 4, and the heat network system is connected to the sludge dryer 2 and / or the heat pump unit 4 is connected to the sludge dryer 2. 2 includes a strip cutter 6, a conveyor belt 7, and a fan 8 in the drying chamber, and a cooler 9 and a heater 10 in the dehumidification chamber. The strip cutter 6 is placed above the conveyor belt 7. The cooler 9 is connected to the drying chamber. The heat network system is connected to the heater 10. The heater 10 is connected to the drying chamber. The heat pump unit 4 is connected to the heater 10. The top of the absorption tower 3 is equipped with a chimney 11, which is connected to the flue gas duct 1 at the tail end of the gas boiler. The sludge dryer 2 is a belt dryer.
[0024] Embodiment 6 of this utility model: A sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler, comprising a gas-fired boiler tail gas duct 1 and a sludge dryer 2. The gas-fired boiler tail gas duct 1 is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the gas-fired boiler tail gas duct 1 and the absorption tower 3. A heat network system is installed on the heat pump unit 4, and the heat network system is connected to the sludge dryer 2 and / or the heat pump unit 4 is connected to the sludge dryer 2. The sludge dryer 2 includes a drying chamber with a cutting edge. The equipment includes a strip cutter 6, a conveyor belt 7, a fan 8, a cooler 9 for the dehumidification chamber, and a heater 10. The strip cutter 6 is positioned above the conveyor belt 7. The cooler 9 is connected to the drying chamber. The heat network system is connected to the heater 10, and the heater 10 is connected to the drying chamber. The heat pump unit 4 is connected to the heater 10. The absorption tower 3 has a chimney 11 at its top, which is connected to the flue gas duct 1 at the tail end of the gas boiler. The sludge dryer 2 is a belt dryer. The heat pump unit 4 is connected to a steam pipe 12.
[0025] Embodiment 7 of this utility model: A sludge drying system utilizing the waste heat of flue gas from a gas-fired boiler, comprising a flue gas duct 1 from the tail end of the gas-fired boiler and a sludge dryer 2. The flue gas duct 1 is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the flue gas duct 1 and the absorption tower 3. A heat network system is installed on the heat pump unit 4, and the heat network system is connected to the sludge dryer 2 and / or the heat pump unit 4 is connected to the sludge dryer 2. The sludge dryer 2 includes a strip cutter 6 in a drying chamber, a conveyor belt 7, and a fan 8. The cooler 9 and heater 10 of the dehumidification chamber are connected. The strip cutter 6 is placed above the conveyor belt 7. The cooler 9 is connected to the drying chamber. The heat network system is connected to the heater 10. The heat pump unit 4 is connected to the heater 10. The top of the absorption tower 3 is equipped with a chimney 11, which is connected to the flue gas pipe 1 at the tail end of the gas boiler. The sludge dryer 2 is a belt dryer. The heat pump unit 4 is connected to a steam pipe 12. The heat network system includes a heat network water supply pipe 13 and a heat network return water pipe 14.
[0026] Embodiment 8 of this utility model: A sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler, comprising a gas-fired boiler tail gas duct 1 and a sludge dryer 2. The gas-fired boiler tail gas duct 1 is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the gas-fired boiler tail gas duct 1 and the absorption tower 3. A heat network system is installed on the heat pump unit 4, and the heat network system is connected to the sludge dryer 2 and / or the heat pump unit 4 is connected to the sludge dryer 2. The sludge dryer 2 includes a strip cutter 6, a conveyor belt 7, a fan 8 in the drying chamber, and a cooler 9 and a heater 10 in the dehumidification chamber. The strip cutter 6... The heat pump unit 4 is connected to the heater 10, which is located above the conveyor belt 7. The heat pump unit 4 is connected to the heater 10. The top of the absorption tower 3 is equipped with a chimney 11, which is connected to the flue gas pipe 1 at the tail end of the gas boiler. The sludge dryer 2 is a belt dryer. The heat pump unit 4 is connected to a steam pipe 12. The heat pump system includes a heat pump water supply pipe 13 and a heat pump water return pipe 14. The heat pump water supply pipe 13 is connected to the inlet of the heater 10, and the heat pump water return pipe 14 is connected to the outlet of the heater 10.
[0027] Embodiment 9 of this utility model: A sludge drying system utilizing the waste heat of flue gas from a gas-fired boiler, comprising a flue gas duct 1 from the tail end of the gas-fired boiler and a sludge dryer 2. The flue gas duct 1 is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the flue gas duct 1 and the absorption tower 3. A heat network system is installed on the heat pump unit 4 and connected to the sludge dryer 2. The sludge dryer 2 includes a strip cutter 6, a conveyor belt 7, and a fan 8 in the drying chamber, and a cooler 9 and a heater 10 in the dehumidification chamber. The absorber tower 3 is located above the conveyor belt 7. The cooler 9 is connected to the drying chamber, and the heat network system is connected to the heater 10. The heater 10 is connected to the drying chamber, and the cooler 9 is connected to the heater 10. The top of the absorber tower 3 is equipped with a chimney 11, which is connected to the flue gas pipe 1 at the tail end of the gas boiler. The sludge dryer 2 is a belt dryer. The heat pump unit 4 is connected to a steam pipe 12. The heat network system includes a heat network water supply pipe 13 and a heat network water return pipe 14. The heat network water supply pipe 13 is connected to the inlet of the heater 10, and the heat network water return pipe 14 is connected to the outlet of the heater 10.
[0028] Embodiment 10 of this utility model: A sludge drying system utilizing the waste heat of flue gas from a gas-fired boiler, comprising a flue gas duct 1 from the tail end of the gas-fired boiler, and a sludge dryer 2. The flue gas duct 1 is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the flue gas duct 1 and the absorption tower 3. A heat network system is installed on the heat pump unit 4, which is connected to the sludge dryer 2. The sludge dryer 2 includes a strip cutter 6, a conveyor belt 7, and a fan 8 in the drying chamber, and a cooler 9 and a heater 10 in the dehumidification chamber. The strip cutter 6 is placed... Above the conveyor belt 7, the cooler 9 is connected to the drying chamber, and the heater 10 is connected to the drying chamber. The heat pump unit 4 is connected to the heater 10. The top of the absorption tower 3 is equipped with a chimney 11, which is connected to the flue gas pipe 1 at the tail end of the gas boiler. The sludge dryer 2 is a belt dryer. The heat pump unit 4 is connected to a steam pipe 12. The heating network system includes a heating network water supply pipe 13 and a heating network water return pipe 14. The heating network water supply pipe 13 is connected to the inlet of the heater 10, and the heating network water return pipe 14 is connected to the outlet of the heater 10.
[0029] Embodiment 11 of this utility model: A sludge drying system utilizing the waste heat of flue gas from a gas-fired boiler, comprising a flue gas duct 1 from the tail end of the gas-fired boiler and a sludge dryer 2. The flue gas duct 1 is connected to an absorption tower 3, and a heat pump unit 4 is connected to the absorption tower 3. A booster fan 5 is installed between the flue gas duct 1 and the absorption tower 3. A heat network system is installed on the heat pump unit 4, and the heat network system is connected to the sludge dryer 2. The heat pump unit 4 is also connected to the sludge dryer 2. The sludge dryer 2 includes a strip cutter 6, a conveyor belt 7, and a fan 8 in the drying chamber, and a cooler 9 and a heater 10 in the dehumidification chamber. The strip cutter 6... The heat pump unit 4 is connected to the heater 10, which is located above the conveyor belt 7. The heat pump unit 4 is connected to the heater 10. The top of the absorption tower 3 is equipped with a chimney 11, which is connected to the flue gas pipe 1 at the tail end of the gas boiler. The sludge dryer 2 is a belt dryer. The heat pump unit 4 is connected to a steam pipe 12. The heat pump system includes a heat pump water supply pipe 13 and a heat pump water return pipe 14. The heat pump water supply pipe 13 is connected to the inlet of the heater 10, and the heat pump water return pipe 14 is connected to the outlet of the heater 10.
[0030] The working principle of one embodiment of this utility model is as follows: When this utility model is working, in the flue gas pipeline 1 at the tail end of the gas boiler, the 88°C flue gas generated by the gas boiler enters the system under the action of the booster fan 5. First, it enters the absorption tower 3. The flue gas flows from bottom to top in the absorption tower 3, is washed by the intermediate medium sprayed from top to bottom, and directly contacts the intermediate substance for heat exchange, recovering some heat and absorbing some harmful gases. The cooled flue gas is discharged through the chimney 11 at the top of the absorption tower. The flue gas outlet temperature drops to 30°C. The heat pump unit 4 is used to realize heat exchange between the intermediate medium and the heat network system pipeline, heating the circulating water in the pipeline from 20°C to 90°C.
[0031] The aforementioned 90℃ circulating water can provide heat for the heating network system and also serve as a heat source for sludge drying. When circulating water is used as a heat source for sludge drying, the following schemes apply: Case 1: After being heated by heat pump unit 4, the circulating water directly enters sludge dryer 2. After heat exchange, the return water is recycled back to heat pump unit 4 for heat exchange again. Case 2: After being heated by heat pump unit 4, the circulating water first enters the heating network system. A branch pipe is led from the heating network water supply pipeline 13 to the sludge dryer. After heat exchange, the return water is connected to the heating network return water pipeline 14 and recycled back to heat pump unit 4 together with the heating network return water for heat exchange again.
[0032] In the sludge dryer 2, wet sludge with a moisture content of 60%-80% is cut into strips by the strip cutter 6 and falls onto the conveyor belt 7 inside the insulated box, where it is evenly distributed. As the sludge moves with the conveyor belt 7, the moisture is carried away by the dry hot air provided by the blower 8. The dried sludge is discharged at the end of the final conveyor belt. The warm and humid air enters the dehumidification chamber, and the cooler 10 converts the moisture carried by the warm and humid air into condensate, which is then discharged from the sludge dryer 2. The dehydrated air enters the heater 10, and 90°C circulating water is used as the inlet water for the heater 10. After being heated, it forms dry hot air, which enters the conveyor belt 7 under the action of the blower 8 to dehydrate the sludge. After low-temperature waste heat drying treatment, the moisture content of the sludge is reduced to 30%, and the calorific value of the dried sludge can reach the level of biomass fuel.
Claims
1. A sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler, comprising a tail gas duct (1) of the gas-fired boiler, characterized in that, It also includes a sludge dryer (2), the flue gas duct (1) at the tail of the gas boiler is connected to an absorption tower (3), a heat pump unit (4) is connected to the absorption tower (3), a booster fan (5) is installed between the flue gas duct (1) at the tail of the gas boiler and the absorption tower (3), a heat network system is installed on the heat pump unit (4), the heat network system is connected to the sludge dryer (2) and / or the heat pump unit (4) is connected to the sludge dryer (2).
2. The sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler according to claim 1, characterized in that, The sludge dryer (2) includes a strip cutter (6), a conveyor belt (7), a fan (8) in the drying chamber, and a cooler (9) and a heater (10) in the dehumidification chamber. The strip cutter (6) is placed above the conveyor belt (7). The cooler (9) is connected to the drying chamber. The heating network system is connected to the heater (10). The heater (10) is connected to the drying chamber. The cooler (9) is connected to the heater (10).
3. A sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler, as described in claim 2, is characterized in that... The heat pump unit (4) is connected to the heater (10).
4. A sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler according to claim 1, characterized in that, The absorption tower (3) is equipped with a chimney (11) at the top, and the chimney (11) is connected to the flue gas pipe (1) at the tail end of the gas boiler.
5. A sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler according to claim 1, characterized in that, The sludge drying machine (2) is a belt dryer.
6. A sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler according to claim 1, characterized in that, The heat pump unit (4) is connected to a steam pipe (12).
7. A sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler according to claim 2, characterized in that, The heating network system includes a heating network water supply pipe (13) and a heating network return water pipe (14).
8. A sludge drying system utilizing waste heat from the tail gas of a gas-fired boiler, as described in claim 7, is characterized in that... The heating network water supply pipe (13) is connected to the inlet of the heater (10), and the heating network return water pipe (14) is connected to the outlet of the heater (10).