Waste heat recovery device for pollution discharge hot water of garbage power plant
By designing vacuum tanks, ejectors, heating coils and other components in the waste-to-energy plant, the sewage is converted into steam, solving the problem of unutilized heat in the sewage, saving fuel and desalted water costs, and achieving energy-saving and environmental protection effects.
Patent Information
- Application Number
- CN202422792135.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-15
- Publication Date
- 2025-09-16
- Estimated Expiration
- 2034-11-15
AI Technical Summary
In the existing technology, the heat of wastewater from waste-to-energy plants cannot be effectively recovered and utilized, resulting in high fuel consumption and high desalted water costs, making it difficult to meet energy-saving and environmental protection requirements.
A device consisting of a vacuum tank, an ejector, a heating coil and a deaerator is designed to convert wastewater into steam through a mixture of high-temperature and low-temperature steam and recycle it, thereby reducing the steam consumption of the deaerator and the cost of desalted water.
It realizes the effective recovery of wastewater heat energy, reduces fuel consumption and desalted water costs, and meets the requirements of energy conservation and environmental protection.
Smart Images
Figure CN223345375U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of garbage power plants, in particular to a waste heat recovery device for sewage hot water discharged from a garbage power plant. Background Art
[0002] In order to control the water quality of boiler water to meet the specified requirements and keep the impurities in the boiler water within a certain limit, it is necessary to continuously remove boiler water with high salt and alkali content and deposited slag, sludge, and soft sediments from the boiler. Boiler blowdown is divided into continuous blowdown and periodic blowdown. Continuous blowdown requires continuous discharge of part of the boiler water from the part with the highest salt and alkali concentration in the boiler water to reduce the salt, alkali, silica content and suspended slag content in the boiler water. Periodic blowdown mainly removes sediments such as slag and mud in the boiler water, so its discharge port is mostly set at the lower part of the boiler drum and the bottom of the header.
[0003] The boiler blowdown rate is generally 3% of the boiler capacity. In order to recycle the considerable heat brought out by this part of the drainage, a boiler blowdown tank is usually set up in the boiler room. The function of the boiler blowdown tank is to recover the heat of the boiler sewage. The low-pressure steam obtained by pressure reduction and evaporation is used for thermal deoxidation and heating boiler feed water. The reduced-pressure sewage (usually with a temperature of 80°C) is discharged into the ditch. If this part of the sewage can be converted into steam for recycling, it can not only reduce fuel consumption and effectively reduce the operating cost of the boiler, but also save a lot of desalted water costs, which meets the requirements of energy conservation and environmental protection. Therefore, we have proposed a waste heat recovery device for sewage hot water in a waste power plant to solve the above problems. Utility Model Content
[0004] The purpose of the utility model is to provide a waste heat recovery device for hot water discharged from waste power plants, so as to solve the problem proposed in the above background technology that if this part of the sewage can be converted into steam for recycling, it can not only reduce fuel consumption and effectively reduce boiler operating costs, but also save a large amount of desalted water costs, which meets the requirements of energy conservation and environmental protection.
[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a waste heat recovery device for waste water hot water discharged from a garbage power plant, comprising a vacuum tank and a deaerator;
[0006] Also includes:
[0007] The ejector is arranged on one side of the vacuum tank, the ejector is arranged at the outlet of the vacuum tank and the other end of the ejector is connected to the deaerator, one end of the vacuum tank is connected to the low-temperature air preheater, and one end of the ejector is connected to the high-temperature air preheater.
[0008] Preferably, a heating coil is provided inside the vacuum tank, and one end of the heating coil is connected to the low-temperature air preheater.
[0009] Preferably, a water pump is provided at the other end of the heating coil, and the other end of the water pump is connected to the deaerator.
[0010] Preferably, a sewage outlet is provided at the bottom of the vacuum tank, and a water inlet is installed on one side of the vacuum tank.
[0011] Compared with the prior art, the beneficial effects of the present invention are:
[0012] First, a vacuum tank is installed, with a heating coil installed inside. A steam ejector is placed at the tank outlet. The high-pressure waste steam from the high-temperature air preheater is used to draw the pressure down to 0.2 atmospheres (20 kPa). 80°C wastewater is then discharged through the water inlet. Simultaneously, low-pressure waste steam from the low-temperature air preheater passes through the heating coil to heat the wastewater. Since the saturation temperature of water at 20 kPa is approximately 60°C, the low-pressure waste steam heats the 80°C wastewater, converting 90% of it to 60°C (0.2 kg) of low-pressure steam. This steam then mixes with the 20 kg high-pressure steam from the high-temperature air preheater in the ejector, converting it into approximately 5 kg of steam that enters the deaerator to heat the boiler feed water. The remaining 10% of wastewater, highly contaminated with impurities, is discharged into the sewer. The low-pressure waste steam discharged from the low-temperature air preheater is converted into high-temperature condensate after being heated by the coil to heat the wastewater (providing the energy required for wastewater vaporization). The condensate is then pumped back to the deaerator as boiler feed water. This can recover the pressure energy of the high-pressure waste steam discharged from the high-temperature air preheater and convert the wastewater into steam. This not only recovers the heat energy of the wastewater, but also reduces the steam consumption of the deaerator and the treatment cost of the boiler desalted water. In addition, the heat energy of the low-pressure waste steam discharged from the low-temperature air preheater can be recovered. BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Figure 1 This is the overall structural system diagram of the utility model;
[0014] In the figure: 1. Vacuum tank; 2. Deaerator; 3. Water inlet; 4. Ejector; 5. Heating coil; 6. Sewage outlet; 7. Water pump; 8. Low-temperature air preheater; 9. High-temperature air preheater. DETAILED DESCRIPTION
[0015] 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 the embodiments.
[0016] The present invention provides a waste heat recovery device for waste water hot water discharged from a garbage power plant, comprising a vacuum tank 1 and a deaerator 2. The present invention primarily addresses the problem of converting this waste water into steam for recycling, thereby reducing fuel consumption and effectively lowering boiler operating costs, while also saving a significant amount of desalted water costs and meeting energy conservation and environmental protection requirements.
[0017] For the device provided by this utility model, please refer to Figure 1 , the following is a detailed introduction.
[0018] One end of the vacuum tank 1 is connected to a low-temperature air preheater 8, and one end of the ejector 4 is connected to a high-temperature air preheater 9. A heating coil 5 is provided inside the vacuum tank 1, and one end of the heating coil 5 is connected to the low-temperature air preheater 8. The high-pressure waste steam discharged from the high-temperature air preheater 9 is used to reduce the pressure in the vacuum tank 1 to 0.2 atmospheres (20kPa), and then 80°C sewage is discharged from the water inlet 3. At the same time, the low-pressure waste steam from the low-temperature air preheater 8 heats the sewage through the heating coil 5 (providing the energy required for sewage vaporization). The 80°C sewage can be heated by 90% to 60°C (0 .2 kg) of low-pressure steam; the ejector 4 is arranged on one side of the vacuum tank 1, and the ejector 4 is arranged at the outlet of the vacuum tank 1. The other end of the ejector 4 is connected to the deaerator 2. The low-pressure steam of 60°C (0.2 kg) discharged from the vacuum tank is mixed with the high-pressure steam with a pressure of 20 kg discharged from the high-temperature air preheater 9 in the ejector 4 to become about 5 kg of steam and enter the deaerator 2 to heat the boiler feed water. The other end of the heating coil 5 is provided with a water pump 7, and the other end of the water pump 7 is connected to the deaerator 2. The low-pressure waste steam discharged from the low-temperature air preheater 8 is converted into high-temperature condensate after heating the sewage through the coil, and is sent back to the deaerator 2 by the water pump 7 as boiler feed water.
[0019] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.
Claims
1. A waste heat recovery device for waste water hot water discharged from a garbage power plant, comprising a vacuum tank (1) and a deaerator (2); Its characteristics are: Also includes: An ejector (4) is arranged on one side of the vacuum tank (1), the ejector (4) is arranged at the outlet of the vacuum tank (1), and the other end of the ejector (4) is connected to the deaerator (2), one end of the vacuum tank (1) is connected to a low-temperature air preheater (8), and one end of the ejector (4) is connected to a high-temperature air preheater (9).
2. The waste heat recovery device for waste-to-energy plant sewage hot water according to claim 1, characterized in that: A heating coil (5) is provided inside the vacuum tank (1), and one end of the heating coil (5) is connected to a low-temperature air preheater (8).
3. The waste heat recovery device for waste-to-energy plant sewage hot water according to claim 2, characterized in that: A water pump (7) is provided at the other end of the heating coil (5), and the other end of the water pump (7) is connected to the deaerator (2).
4. The waste heat recovery device for waste-to-energy plant sewage hot water according to claim 1, characterized in that: A sewage outlet (6) is provided at the bottom of the vacuum tank (1), and a water inlet (3) is installed on one side of the vacuum tank (1).