System for realizing zero discharge of concentrated desulfurization wastewater of power plant by using slag dryer

Abstract

The utility model discloses a system for realizing zero discharge of concentrated desulfurization waste water of a power plant by utilizing a slag dryer, which relates to the technical field of waste water discharge and comprises the slag dryer passing through a conveying and lifting mechanism on the slag dryer. The slag storage mechanism is arranged at the output end of the slag drying machine; the slag conveying vehicle is used for collecting the disintegrating slag discharged by the slag storage mechanism; the waste water coupling assembly is communicated with the slag hopper, the slag drying machine and the slag conveying vehicle through a plurality of spraying assemblies. According to the system for realizing zero emission of the concentrated desulfurization wastewater of the power plant by utilizing the slag dryer, three-section spraying is realized through the wastewater coupling assembly: a plurality of nozzles in the slag hopper instantly evaporate high-temperature disintegrating slag at 500-600 DEG C, a splitter plate nozzle at a conveying section of the slag dryer dynamically sprays and loosens the disintegrating slag, and a splitter box at an outlet of a slag bin inhibits flying dust and evaporates residual water; a closed loop of high-temperature rapid evaporation, medium-temperature uniform curing and low-temperature dust suppression is formed, and the wastewater evaporation efficiency is greatly improved.

Description

Technical Field

[0001] This utility model relates to the field of wastewater discharge technology, specifically a system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine. Background Technology

[0002] The heat generated by the dry slag from the boiler of a normally operating coal-fired power plant is insufficient to completely evaporate the desulfurization wastewater. Furthermore, the dry slag treatment and temperature, along with the flow rate of the desulfurization wastewater, change dynamically with the load. Excessive spraying of desulfurization wastewater necessitates, on the one hand, increasing the corrosion resistance of the dry slag machine materials and raising costs, and on the other hand, it easily leads to caking and blockage of the dry slag machine.

[0003] Utility model patent CN208869345U discloses a zero-discharge device for desulfurization wastewater used for dry slag cooling, including a flash evaporation concentration system, a gas-liquid condensation system, and a dry slag spraying system. The flash evaporation concentration system includes a desulfurization tower, a slurry circulation spraying device, a desulfurization tower demister, a slurry circulation pipeline, a heat exchanger, a desulfurization wastewater clear liquid circulation pipeline, a flash evaporation tower, a flash evaporation tower spraying device, a flash evaporation tower demister, a desulfurization wastewater conveying pipeline, a buffer tank, a stirring device, and a desulfurization wastewater inlet pipeline. The dry slag spraying system includes a desulfurization wastewater concentrate conveying pipeline, a flow meter, a variable frequency desulfurization wastewater concentrate conveying pump, a dry slag spraying device, a dry slag machine, a thermometer, a slag metering device, and an air compressor.

[0004] As shown in the above-mentioned utility model, existing zero-discharge devices for desulfurization wastewater can automatically adjust the spray volume of concentrated desulfurization wastewater, utilize clean water, save water, improve desulfurization efficiency, reduce flue gas temperature, and synergistically remove pollutants and achieve ultra-clean emissions. However, traditional zero-discharge devices for desulfurization wastewater rely on flash tower stratified concentration and indirect heat exchange through condenser. During flash evaporation, the wastewater atomization is uneven, resulting in low evaporation efficiency. Furthermore, the condenser adopts a shell-and-tube structure, with heat exchange between cooling water and water vapor through the inter-wall, limiting condensation efficiency and requiring additional energy to maintain vacuum, resulting in high overall system energy consumption. Moreover, existing dry slag spraying devices use single-fluid nozzles, resulting in larger atomized particles, a small contact area with high-temperature slag, and a slow evaporation rate. The spray volume relies solely on manual adjustment and cannot be dynamically matched according to the slag temperature, easily leading to excessive wastewater residue or excessive dust emissions. Utility Model Content

[0005] To address the shortcomings of existing technologies, this invention provides a system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine, thus solving the aforementioned problems.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine, comprising:

[0007] The dry slag machine, through its conveying and lifting mechanism, is used to transport the crushed slag at the discharge port to the slag storage mechanism. A slag hopper is provided above the input end of the dry slag machine.

[0008] A slag storage mechanism is provided at the output end of the dry slag machine and is used to store crushed slag.

[0009] A slag-carrying vehicle, which is used to collect the slag discharged from the slag storage mechanism;

[0010] A wastewater coupling component is installed between the slag dryer and the slag storage mechanism. The wastewater coupling component is connected to the slag hopper, the slag dryer and the slag transport vehicle through multiple spray components to achieve zero wastewater discharge.

[0011] Preferably, the dry slag machine includes a frame, one end of which is connected to a conveyor belt via two guide rollers, the other end of which is connected to a lifting belt via two guide rollers, and a discharge port is provided at the bottom of the other end of the frame.

[0012] Preferably, a transmission box is provided on one side of the middle part of the frame, the input ends of two adjacent guide rollers are connected to the pulleys in the transmission box, a motor is installed on the outside of the transmission box, and the output end of the motor is connected to the drive wheel in the transmission box.

[0013] Preferably, the slag storage mechanism includes a slag bin, with bin wall vibrators installed at the lower ends of both sides of the slag bin, a slag crusher installed on one side of the top of the slag bin, the input end of the slag crusher being located below the discharge port of the dry slag machine, and a bag filter installed on the other side of the top of the slag bin, with a vacuum pressure valve installed on one side of the bag filter.

[0014] Preferably, the bottom of the slag bin is provided with a discharge port, a manual slide valve is provided on one side of the upper end of the discharge port, a pneumatic slide valve is provided on the other side of the lower end of the discharge port, and a slag transport vehicle is provided below the discharge port.

[0015] Preferably, the wastewater coupling assembly includes a wastewater tank, the output end of which is connected to a water pipe. A solenoid valve is installed at the connection between the water pipe and the wastewater tank. The output end of the water pipe is connected to a first nozzle installed inside the discharge port, a diversion plate installed on the frame, and a diversion box installed above the slag transport vehicle. Multiple first nozzles are provided, and the multiple first nozzles are distributed in a linear array on the inner walls of both sides of the discharge port. Multiple diversion plates are provided, and the multiple diversion plates are equally spaced above the lifting belt. Multiple equally spaced nozzles are provided on the lower surface of the diversion plates and the diversion box for spraying desulfurization wastewater onto the high-temperature slag for evaporation.

[0016] Beneficial effects

[0017] This invention provides a system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine.

[0018] Compared with existing technologies, it has the following advantages:

[0019] 1. This system, which utilizes a dry slag machine to achieve zero discharge of concentrated desulfurization wastewater from power plants, achieves three-stage spraying through wastewater coupling components: multiple nozzles in the slag hopper instantaneously evaporate the 500-600℃ high-temperature slag, the nozzles on the diversion plate of the dry slag machine conveying section dynamically spray the loose slag, and the diversion box at the slag bin outlet suppresses dust and evaporates residual moisture, forming a closed loop of "high-temperature rapid evaporation - medium-temperature uniform solidification - low-temperature dust suppression", which greatly improves the wastewater evaporation efficiency.

[0020] 2. This system, which utilizes a dry slag machine to achieve zero discharge of concentrated desulfurization wastewater from power plants, prevents slag caking through the slag storage mechanism's silo wall vibrator, collects dust through a bag filter, and ensures that water and steam emissions comply with GB13223-2011 standards through a vacuum pressure valve. It solves the secondary pollution problem of traditional equipment from the source and achieves the dual goals of zero wastewater discharge and clean production. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of this utility model.

[0022] Figure 2 This is a schematic diagram of the dry slag machine of this utility model.

[0023] Figure 3 This is a schematic diagram of the slag storage mechanism of this utility model.

[0024] Figure 4 This is a schematic diagram of the wastewater coupling component structure of this utility model.

[0025] In the diagram: 1. Dry slag machine, 11. Frame, 12. Conveyor belt, 13. Elevator belt, 14. Transmission box, 15. Motor, 16. Discharge port, 2. Slag hopper, 3. Slag storage mechanism, 31. Slag bin, 32. Crusher, 33. Bag filter, 34. Vacuum pressure valve, 35. Discharge port, 36. Manual slide gate valve, 37. Start slide gate valve, 4. Slag transport vehicle, 5. Wastewater coupling assembly, 51. Wastewater tank, 52. Water pipe, 53. First nozzle, 54. Diverter plate, 55. Diverter box. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] Please see Figure 1-4 This utility model provides two technical solutions:

[0028] The first implementation method is a system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine, comprising a dry slag machine 1, a slag storage mechanism 3, and a wastewater coupling component 5.

[0029] Specifically, the dry slag machine 1 uses its conveying and lifting mechanism to transport the crushed slag at the discharge port 16 to the slag storage mechanism 3. A slag hopper 2 is provided above the input end of the dry slag machine 1. The dry slag machine 1 includes a frame 11. One end of the frame 11 is connected to a conveyor belt 12 via two guide rollers. The other end of the frame 11 is connected to a lifting belt 13 via two guide rollers. A discharge port 35 is provided at the bottom of the other end of the frame 11. A transmission box 14 is provided on one side of the middle of the frame 11. The input ends of two adjacent guide rollers are connected to pulleys inside the transmission box 14. A motor 15 is installed on the outside of the transmission box 14. The output end of the motor 15 is connected to the drive wheel inside the transmission box 14.

[0030] More specifically, the slag storage mechanism 3 is located at the output end of the dry slag machine 1 and is used to store crushed slag. The slag storage mechanism 3 includes a slag bin 31. Both sides of the lower end of the slag bin 31 are equipped with bin wall vibrators. A crusher 32 is installed on one side of the top of the slag bin 31. The input end of the crusher 32 is located below the discharge port 35 of the dry slag machine 1. A bag filter 33 is installed on the other side of the top of the slag bin 31. A vacuum pressure valve 34 is installed on one side of the bag filter 33 to filter out a small amount of water vapor and dust generated during the spray evaporation process. The dust is captured by the bag filter 33 and returned to the slag bin 31 to mix with the crushed slag. The water vapor is discharged into the atmosphere through the vacuum pressure valve 34 to ensure that the emission complies with GB13223-2011 "Emission Standard of Air Pollutants for Thermal Power Plants". The bottom of the slag bin 31 is provided with a discharge port 35. A manual slide valve 36 is provided on one side of the upper end of the discharge port 35, and a pneumatic slide valve 37 is provided on the other side of the lower end of the discharge port 35. A slag transport vehicle 4 is provided below the discharge port 35. The slag transport vehicle 4 is used to collect the broken slag discharged by the slag storage mechanism 3.

[0031] The second implementation differs from the first in that the wastewater coupling component 5 is positioned between the dry slag machine 1 and the slag storage mechanism 3. The wastewater coupling component 5 is connected to the slag hopper 2, the dry slag machine 1, and the slag transport vehicle 4 via multiple spray components to achieve zero wastewater discharge. The wastewater coupling component 5 includes a wastewater tank 51, with a water pipe 52 connected to the output end of the wastewater tank 51. A solenoid valve is installed at the connection between the water pipe 52 and the wastewater tank 51. The wastewater tank 51 stores concentrated desulfurization wastewater. The total spray volume is precisely controlled by the solenoid valve on the water pipe 52, and is proportionally linked to the slag flow rate (e.g., 1 kg of slag). It is equipped with 0.2-0.5L of wastewater. The output end of the water pipe 52 is connected to a first nozzle 53 installed inside the discharge port 16, a diversion plate 54 installed on the frame 11, and a diversion box 55 set above the slag transport vehicle 4. Multiple first nozzles 53 are provided, and multiple first nozzles 53 are distributed in a linear array on the inner walls of both sides of the slag hopper 2. Multiple diversion plates 54 are provided, and multiple diversion plates 54 are equally spaced above the lifting belt 13. Multiple equally spaced nozzles are provided on the lower surface of the diversion plate 54 and the diversion box 55, which are used to spray the desulfurization wastewater onto the high-temperature crushed slag for evaporation.

[0032] When this device is in operation, the high-temperature slag discharged from the boiler (temperature of about 300-600℃) enters the dry slag machine 1 through the slag hopper 2. The conveyor belt 12 and the lifting belt 13 are driven by the motor 15 (through the pulley group in the transmission box 14) to transport the slag from the lower position to the slag storage mechanism 3 at the higher position. During the transportation process, the residual heat (sensible heat) carried by the slag becomes the core heat source for evaporating the wastewater. Its temperature and flow rate are adjusted by the speed of the motor 15 to ensure the efficiency of subsequent spray evaporation. Before the slag enters the slag bin 31 of the slag storage mechanism 3 through the discharge port 35, it is first crushed to a uniform particle size by the slag crusher 32 at the top to increase the surface area and improve the evaporation efficiency of the wastewater. The bin wall vibrators on both sides of the slag bin 31 work periodically to prevent the slag from accumulating and caking, ensuring that the slag layer is loose and facilitates uniform contact after the wastewater is sprayed.

[0033] Slag hopper spraying at the discharge port: The first nozzles 53, linearly arrayed on the inner walls of both sides of the slag hopper 2, spray concentrated desulfurization wastewater onto the slag that has just entered the conveyor belt 12. The initial temperature of the slag is as high as 500-600℃. The wastewater evaporates immediately upon contact, and the water vaporizes rapidly. Salts (such as NaCl and CaSO4) adhere to the surface of the slag. The temperature distribution and accumulation volume of the slag in the slag hopper are monitored in real time by a dual-spectrum imager or electromagnetic radar (not shown in the figure), and the feedback is sent to the control system to automatically adjust the opening of the solenoid valve and control the spraying volume (e.g., increase the spraying frequency when the temperature is >500℃ and decrease it when the temperature is <300℃) to avoid excessive wastewater causing the slag to stick together.

[0034] Dynamic spraying in the conveyor section: Diverter plates 54 are evenly spaced above the lifting belt 13, with nozzles on their lower surfaces continuously spraying the moving debris. As the debris is conveyed upwards with the lifting belt 13, it is in a dynamically loose state. The nozzles atomize the wastewater and spray it evenly, ensuring full contact with the debris particles (contact area increased by 30%). The wastewater evaporates and absorbs the sensible heat of the debris, reducing the debris temperature to 200-300℃. At the same time, the salt in the wastewater is adsorbed or encapsulated by the pores of the debris, forming solidified crystals (such as Ca2+ and SO42- forming calcium sulfate precipitate). The tilt angle of the diverter plates 54 (15°-30° with the horizontal plane) is designed to guide the atomized droplets to spray along the direction of debris movement, reducing splash loss.

[0035] Dust suppression spray at the slag bin outlet: The slag falling down to the slag bin 4 through the diversion box 55 above the slag transport vehicle 4 is sprayed for the final time. When the slag is discharged through the manual slide valve 36 and the pneumatic slide valve 37 of the slag bin 31, dust may be generated. The sprayed wastewater can suppress the dust. The residual moisture is finally evaporated in the slag transport vehicle 4 to ensure that the moisture content of the discharged slag-salt mixture is <5%, which meets the requirements for subsequent landfill or comprehensive utilization.

[0036] Furthermore, all content not described in detail in this specification is existing technology known to those skilled in the art, and the model parameters of each electrical appliance are not specifically limited; conventional equipment can be used.

[0037] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0038] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine, characterized in that, include: The dry slag machine, through its conveying and lifting mechanism, is used to transport the crushed slag at the discharge port to the slag storage mechanism. A slag hopper is provided above the input end of the dry slag machine. A slag storage mechanism is provided at the output end of the dry slag machine and is used to store crushed slag. A slag-carrying vehicle, which is used to collect the slag discharged from the slag storage mechanism; A wastewater coupling component is installed between the slag dryer and the slag storage mechanism. The wastewater coupling component is connected to the slag hopper, the slag dryer and the slag transport vehicle through multiple spray components to achieve zero wastewater discharge.

2. The system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine according to claim 1, characterized in that: The dry slag machine includes a frame, with a conveyor belt connected to one end of the frame via two guide rollers, and a lifting belt connected to the other end of the frame via two guide rollers. A discharge port is provided at the bottom of the other end of the frame.

3. A system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine according to claim 2, characterized in that: A transmission box is provided on one side of the middle part of the frame. The input ends of two adjacent guide rollers are connected to the pulleys inside the transmission box. A motor is installed on the outside of the transmission box, and the output end of the motor is connected to the drive wheel inside the transmission box.

4. A system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine according to claim 1, characterized in that: The slag storage mechanism includes a slag bin, with bin wall vibrators installed at the lower ends of both sides of the slag bin. A slag crusher is installed on one side of the top of the slag bin, with the input end of the slag crusher located below the discharge port of the dry slag machine. A bag filter is installed on the other side of the top of the slag bin, with a vacuum pressure valve installed on one side of the bag filter.

5. A system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine according to claim 4, characterized in that: The bottom of the slag bin is provided with a discharge port. A manual slide valve is provided on one side of the upper end of the discharge port, and a pneumatic slide valve is provided on the other side of the lower end of the discharge port. A slag transport vehicle is provided below the discharge port.

6. A system for achieving zero discharge of concentrated desulfurization wastewater from power plants using a dry slag machine according to claim 1, characterized in that: The wastewater coupling assembly includes a wastewater tank, the output end of which is connected to a water pipe. A solenoid valve is installed at the connection between the water pipe and the wastewater tank. The output end of the water pipe is connected to a first nozzle installed inside the discharge port, a diversion plate installed on the frame, and a diversion box installed above the slag transport vehicle. Multiple first nozzles are provided, and the multiple first nozzles are distributed in a linear array on the inner walls on both sides of the discharge port. Multiple diversion plates are provided, and the multiple diversion plates are equally spaced above the lifting belt. Multiple equally spaced nozzles are provided on the lower surface of the diversion plates and the diversion box for spraying desulfurization wastewater onto the high-temperature slag for evaporation.

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