Reduction system for concentrated salt wastewater of thermal power plant
By setting up bypass flue in the main flue of the thermal power plant and using a wastewater spray device, concentrated salt water is sprayed into the high-temperature flue gas and evaporates and crystallizes, the complex and cost problems of concentrated salt wastewater treatment equipment in the existing technology are solved, and concentrated salt is achieved The reduction of salt wastewater and the zero emission of wet flue gas desulfurization wastewater reduce treatment costs and energy consumption.
Patent Information
- Application Number
- CN202420925405.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-30
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2034-04-30
AI Technical Summary
In the prior art, the concentrated salt wastewater treatment equipment of thermal power plants has complex structure and high cost, making it difficult to achieve zero emission of wet flue gas desulfurization wastewater with low investment.
Set up a bypass flue in the main flue, and a wastewater spray device is arranged in the bypass flue, spray concentrated salt water into high-temperature flue gas and evaporate and crystallize, and use fly ash in the flue gas to collect salt substances to achieve concentrated salt wastewater Zero emissions of wastewater from desulfurization and wet flue gas.
It has achieved the reduction of concentrated salt wastewater in thermal power plants and zero emission of wet flue gas desulfurization wastewater, reducing treatment costs and energy consumption, and has a simple structure, convenient construction and installation, and low manufacturing costs.
Smart Images
Figure CN222204854U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of concentrated salt wastewater treatment in thermal power plants, in particular to a system for reducing concentrated salt wastewater in thermal power plants. Background Art
[0002] In thermal power plants, the water treatment workshop mainly produces desalted water from raw water, which is supplied to steam turbines or waste heat boilers. At present, the water treatment workshop in power plants generally uses membrane method to treat raw water to produce desalted water. In the process of producing desalted water, a large amount of concentrated brine will be produced and stored in the wastewater pool. Concentrated brine contains a large amount of salt and cannot be directly discharged or reused. In the prior art, it is generally discharged after entering the sewage treatment station and being treated with other industrial wastewaters, but the concentrated brine has a high salt content and a large amount of water compared to other wastewaters in thermal power plants, and the treatment cost is high. Flue evaporation technology has begun to be used in zero discharge of desulfurization wastewater in various industries. In the treatment of desulfurization wastewater, the desulfurization wastewater is atomized and sprayed into the flue between the air preheater (APH) and the electrostatic precipitator (ESP). The waste heat of the flue gas is used to completely evaporate the wastewater, and the pollutants in the wastewater are converted into solids such as crystals or salts. They are collected by the electrostatic precipitator together with the fly ash in the flue gas, thereby removing the pollutants. However, the treatment equipment in the prior art is relatively complex in structure and relatively expensive.
[0003] The prior art urgently needs a new technology for treating wet flue gas desulfurization wastewater, which can achieve zero discharge of wet flue gas desulfurization wastewater with low investment. Utility Model Content
[0004] The utility model is to overcome the shortcomings of the above-mentioned prior art and provide a system for reducing concentrated salt wastewater in a thermal power plant. The utility model sets a bypass flue in the main flue, arranges a wastewater spray device in the bypass flue, sprays the concentrated salt water produced in the water treatment workshop into the flue through a wastewater pump, and the concentrated salt water quickly evaporates and crystallizes under the action of high-temperature flue gas. The salt crystals in the concentrated salt wastewater droplets are collected by the dust collector along with the fly ash in the flue gas, and the flue evaporation and crystallization are used to reduce the concentrated salt wastewater in the water treatment workshop of the thermal power plant, and realize zero discharge of wet flue gas desulfurization wastewater. The utility model has a simple structure, is easy to construct and install, and has a low manufacturing cost.
[0005] The technical solution adopted by the utility model to solve its technical problems is:
[0006] A system for reducing concentrated salt wastewater in a thermal power plant comprises a main flue of the thermal power plant, to which a denitration reactor, a primary coal awakener, an air preheater, a low-temperature coal awakener and a dust collector are sequentially connected, a bypass flue connected in parallel with the main flue is provided between the rear of the denitration reactor and the rear of the air preheater outlet, one end of the bypass flue is connected to the main flue at the rear of the denitration reactor, and the other end is connected to the main flue after the air preheater outlet, a smoke inlet is provided on the bypass flue near the main flue at the rear of the denitration reactor, the smoke inlet is connected to a wastewater atomization device, and a bypass valve is provided on the bypass flue near the smoke inlet.
[0007] There are two bypass flues with four smoke outlets. The two bypass flues are symmetrically arranged on both sides of the main flue. The rear ends of the two bypass flues converge into the horizontal main flue at the air preheater outlet. Two of the smoke outlets are arranged on one of the bypass flues, and the other two smoke outlets are arranged on the other bypass flue.
[0008] The wastewater atomization device comprises a wastewater pump and a spray device. The wastewater pump is connected to the spray device through a wastewater pipe. The wastewater pump is connected to a concentrated salt wastewater pool through a pipe. The wastewater pipe is connected to a compressed air pipe. The nozzle of the spray device is arranged on the inner wall of the bypass flue.
[0009] The wastewater pipeline is provided with a flow control valve and a wastewater flow sensor.
[0010] The bypass flue is equipped with a flue gas flow sensor and a temperature sensor.
[0011] The spray device adopts a dual-fluid atomization structure or a rotary atomization structure.
[0012] The flow control valve, wastewater flow sensor, flue gas flow sensor and temperature sensor are respectively connected to the controller.
[0013] The denitration reactor is a selective catalytic reduction denitration reactor.
[0014] The beneficial effects of the utility model are:
[0015] 1. The utility model sets a bypass flue in the main flue, arranges a wastewater spray device in the bypass flue, sprays the concentrated brine produced in the water treatment workshop into the flue through a wastewater pump, and the concentrated brine evaporates and crystallizes rapidly under the action of high-temperature flue gas. The salt crystals in the concentrated salt wastewater droplets are collected by the dust collector along with the fly ash in the flue gas. The flue evaporation and crystallization are used to reduce the concentrated salt wastewater in the water treatment workshop of the thermal power plant, and realize zero discharge of wet flue gas desulfurization wastewater. The utility model has a simple structure, is easy to construct and install, and has a low manufacturing cost.
[0016] 2. The bypass flue of the utility model is provided with two high-temperature flue gas inlet flues, which are taken from the outlet flue of the SCR denitrification reactor. A bypass valve is arranged on the bypass flue. When the amount of water in the concentrated brine pool is large, the wastewater pump and the bypass valve are opened, and the high-temperature flue gas flow rate is adjusted according to the amount of wastewater. This can achieve the reduction of concentrated brine in the thermal power plant and the amount of sewage. Through the control action of the controller, the pressure and flow rate of the spray droplets can be adjusted, the energy consumption is low, and the processing cost is also reduced. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments:
[0018] Figure 1 It is a schematic structural diagram of an embodiment of the present utility model.
[0019] In the figure, there are main flue 1, denitrification reactor 2, bypass flue 3, primary coal awakener 4, air preheater 5, low-temperature coal awakener 6, dust collector 7, wastewater pump 8, spray device 9, bypass valve 10, flow control valve 11, compressed air 12, and concentrated salt wastewater pool 13. DETAILED DESCRIPTION
[0020] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described 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.
[0021] like Figure 1 As shown, a system for reducing concentrated salt wastewater in a thermal power plant comprises a main flue 1 of the thermal power plant, to which a denitration reactor 2, a primary coal awakener 4, an air preheater 5, a low-temperature coal awakener 6 and a dust collector 7 are sequentially connected, and a bypass flue 3 connected in parallel with the main flue 1 is provided between the rear of the denitration reactor 2 and the rear of the air preheater outlet, one end of the bypass flue 3 is connected to the main flue 1 at the rear of the denitration reactor, and the other end is connected to the main flue 1 after the air preheater outlet, a smoke inlet is provided on the bypass flue 3 near the main flue 1 at the rear of the denitration reactor, and the smoke inlet is connected to a wastewater atomization device.
[0022] The denitration reactor 2 is a selective catalytic reduction (SCR) denitration reactor.
[0023] A bypass valve 10 is provided on the bypass flue 3 near the smoke outlet.
[0024] In this embodiment, there may be several bypass flues 3. In this embodiment, there are two bypass flues 3, with four smoke outlets, the two bypass flues 3 are symmetrically arranged on both sides of the main flue, the rear ends of the two bypass flues 3 are gathered into the horizontal main flue 1 at the outlet of the air preheater, two of the smoke outlets are arranged on one of the bypass flues 3, and the other two smoke outlets are arranged on the other bypass flue 3.
[0025] The wastewater atomization device includes a wastewater pump 8 and a spray device 9. The wastewater pump 8 is connected to the spray device 9 through a wastewater pipe. The wastewater pump 8 is connected to a concentrated salt wastewater pool 13 through a pipe. The wastewater pipe is connected to a compressed air 12 pipe. The nozzle of the spray device 9 is arranged on the inner wall of the bypass flue 3.
[0026] The wastewater pipeline is provided with a flow control valve 11 and a wastewater flow sensor, which are not shown in the figure.
[0027] The bypass flue is provided with a flue gas flow sensor and a temperature sensor, which are not shown in the figure.
[0028] The spray device 9 adopts a dual-fluid atomization structure or a rotary atomization structure.
[0029] The bypass valve 10 is a solenoid valve. The solenoid valve, the flow control valve 11, the wastewater flow sensor, the flue gas flow sensor, and the temperature sensor are respectively connected to a controller. The controller is a PLC controller.
[0030] When the utility model is used, concentrated brine is pumped into several spray devices by a wastewater pump, and the wastewater and compressed air are mixed in the spray device 9 to form droplets with a diameter of less than 60 μm, which are then sprayed into the high-temperature flue gas through a nozzle to quickly evaporate and crystallize. The salt contained in the concentrated brine wastewater droplets turns into solids such as crystals or salts, which are collected by the electrostatic precipitator together with the fly ash in the flue gas. The flue gas is discharged from the chimney, and the dry ash is then discharged in real time or regularly according to the situation, thereby achieving the reduction of concentrated brine wastewater in the water treatment workshop. Through the control of the controller, the utility model can realize the automatic adjustment of the pressure and flow rate of the sprayed droplets, with low energy consumption and reduced concentrated brine treatment costs.
[0031] The bypass flue of the utility model is provided with two high-temperature flue gas inlet flues, which are taken from the outlet flue of the SCR denitration reactor, and a bypass valve is provided on the bypass flue. When the amount of water in the concentrated brine pool is large, the wastewater pump and the bypass valve are opened, and the high-temperature flue gas flow rate is adjusted according to the amount of wastewater, so as to achieve the reduction of concentrated brine in the thermal power plant and reduce the amount of sewage. The utility model has a simple structure, is easy to construct and install, and has a low manufacturing cost.
[0032] In the description of the present invention, the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "vertical", "horizontal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the purpose of describing the present invention rather than requiring the present invention to be constructed or operated in a specific position, and therefore cannot be understood as a limitation on the present invention. The terms "connected" and "connected" in the present invention should be understood in a broad sense, for example, it can be a connection or a detachable connection; it can be a direct connection or an indirect connection through an intermediate component. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.
[0033] The above is a preferred embodiment of the present invention, and the description of the specific embodiment is only used to better understand the concept of the present invention. For ordinary technicians in this technical field, several improvements or equivalent substitutions can be made according to the principle of the present invention, and these improvements or equivalent substitutions are also considered to fall within the protection scope of the present invention.
Claims
1. A system for reducing concentrated salt wastewater in a thermal power plant, comprising a main flue of the thermal power plant, It is characterized in that The main flue is connected with a denitration reactor, a primary coal awakener, an air preheater, a low-temperature coal awakener and a dust collector in sequence; a bypass flue connected in parallel with the main flue is provided between the rear of the denitration reactor and the rear of the air preheater outlet; one end of the bypass flue is connected with the main flue at the rear of the denitration reactor, and the other end is connected with the main flue after the air preheater outlet; a smoke outlet is provided on the bypass flue near the main flue at the rear of the denitration reactor, the smoke outlet is connected with a wastewater atomization device, and a bypass valve is provided on the bypass flue near the smoke outlet.
2. The system for reducing concentrated salt wastewater from a thermal power plant according to claim 1, It is characterized in that There are two bypass flues with four smoke outlets. The two bypass flues are symmetrically arranged on both sides of the main flue. The rear ends of the two bypass flues converge into the horizontal main flue at the air preheater outlet. Two of the smoke outlets are arranged on one of the bypass flues, and the other two smoke outlets are arranged on the other bypass flue.
3. The system for reducing concentrated salt wastewater from a thermal power plant according to claim 1, It is characterized in that The wastewater atomization device comprises a wastewater pump and a spray device. The wastewater pump is connected to the spray device through a wastewater pipe. The wastewater pump is connected to a concentrated salt wastewater pool through a pipe. The wastewater pipe is connected to a compressed air pipe. The nozzle of the spray device is arranged on the inner wall of the bypass flue.
4. The system for reducing concentrated salt wastewater from a thermal power plant according to claim 3, It is characterized in that The wastewater pipeline is provided with a flow control valve and a wastewater flow sensor.
5. The system for reducing concentrated salt wastewater from a thermal power plant according to claim 4, It is characterized in that The bypass flue is equipped with a flue gas flow sensor and a temperature sensor.
6. The system for reducing concentrated salt wastewater from a thermal power plant according to claim 3, It is characterized in that The spray device adopts a dual-fluid atomization structure or a rotary atomization structure.
7. The system for reducing concentrated salt wastewater from a thermal power plant according to claim 5, It is characterized in that The flow control valve, wastewater flow sensor, flue gas flow sensor and temperature sensor are respectively connected to the controller.
8. The system for reducing concentrated salt wastewater from a thermal power plant according to claim 1, It is characterized in that The denitration reactor is a selective catalytic reduction denitration reactor.