A large-particle urea dust washing liquid concentration device based on hydrolysis waste heat cascade utilization
Patent Information
- Application Number
- CN202522509345.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-26
- Publication Date
- 2026-10-27
- Estimated Expiration
- 2035-11-26
AI Technical Summary
产生的稀尿素洗涤液需要浓缩后才能返回主工艺系统，传统方法通常直接消耗新鲜蒸汽进行蒸发浓缩，能耗较高；同时，尿素生产中的高温水解废液，其携带的大量余热通常通过循环水冷却直接排放，造成能量浪费；现有技术中，缺乏将这两部分装置有效耦合以实现能量梯级利用和废物资源化的高效集成方案；因此，开发一种基于水解废热梯级利用的大颗粒尿素粉尘洗涤液浓缩装置是十分必要的
[0007]本实用新型突破传统“水解废液直接排放”和“洗涤液新鲜蒸汽加热”的技术瓶颈，通过两级换热实现水解废液余热的最大化回收，降低吨尿素蒸汽消耗，同时减少循环水消耗，减少外排热损失。
Smart Images
Figure CN224893354U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of fertilizer energy-saving production technology, specifically to a large-particle urea dust washing liquid concentration device based on the cascade utilization of hydrolysis waste heat. Background Technology
[0002] Urea is an important nitrogen fertilizer and chemical raw material. During the production of large-particle urea, the granulation tail gas carries a large amount of urea dust, which is typically absorbed and recovered using a washing liquid. The resulting dilute urea washing liquid needs to be concentrated before returning to the main process system. Traditional methods usually consume fresh steam directly for evaporation and concentration, resulting in high energy consumption. Simultaneously, the high-temperature hydrolysis waste liquid from urea production carries a large amount of waste heat, which is usually directly discharged after cooling with circulating water, leading to energy waste. Current technologies lack an efficient integrated scheme that effectively couples these two components to achieve energy cascade utilization and waste resource recovery. Therefore, developing a large-particle urea dust washing liquid concentration device based on the cascade utilization of hydrolysis waste heat is essential. Utility Model Content
[0003] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a large-particle urea dust washing liquid concentration device based on the cascade utilization of hydrolysis waste heat, which has low energy consumption, low investment, and stable operation. Through system integration and cascade utilization of heat energy, energy saving and consumption reduction in the urea production process can be achieved.
[0004] The purpose of this utility model is achieved as follows: A large-particle urea dust washing liquid concentration device based on the cascade utilization of hydrolysis waste heat, comprising a washing pump, an evaporator preheater, an evaporator heater, a flash tank, a melting pump, a melting pump inlet valve, a hydraulic jet, a dust scrubber, a scrubber nozzle, a hydrolysis waste liquid valve, a flash tank level valve, a scrubber nozzle valve, a flash tank vacuum valve, a washing liquid delivery valve, a scrubber level gauge, a flash tank pressure gauge, a flash tank level gauge, a flash tank thermometer, and an umbrella-shaped baffle. The washing pump inlet is connected to the dust scrubber via a pipeline, and the washing pump outlet is connected to the scrubber nozzle valve, the flash tank vacuum valve, and the washing liquid delivery valve via pipelines. The scrubber nozzle valve is connected to the scrubber nozzle via a pipeline, the flash tank vacuum valve is connected to the hydraulic jet via a pipeline, and the washing liquid delivery valve is connected to the evaporator preheater via a pipeline. The process involves connecting the tubes of the evaporator preheater in series with the tubes of the evaporator heater via pipes. The outlet of the evaporator heater tubes is connected in series with the flash tank via pipes. The outlet of the flash tank is connected to the molten pump via the inlet valve and pipes of the molten pump. The outlet of the molten pump is connected to the level valve of the flash tank via pipes. The steam outlet of the flash tank is connected to the shell of the evaporator preheater via pipes. The shell of the evaporator preheater is connected to the dust scrubber via pipes. The outlet of the hydraulic jet is connected to the dust scrubber via pipes. The scrubber nozzle is installed inside the dust scrubber. The hydrolysis waste liquid valve is connected to the shell of the evaporator heater via pipes. The shell of the evaporator heater is connected to the dust scrubber. A level gauge is installed at the bottom of the dust scrubber. A pressure gauge is installed at the top of the flash tank. A level gauge and a thermometer are installed at the bottom of the flash tank. An umbrella-shaped baffle is installed above the outlet of the tubes of the evaporator heater inside the flash tank.
[0005] During operation, the hydrolysis waste liquid valve is opened, and the waste liquid enters the dust scrubber through the shell of the evaporator heater. When the scrubber level gauge shows 50%, the scrubbing pump is started, and the scrubber nozzle valve is opened to send the scrubbing liquid to the scrubber nozzles to complete the spray absorption cycle. The scrubbing delivery valve is opened to send the scrubbing liquid to the tube side of the evaporator preheater to complete the scrubbing liquid concentration and delivery. The scrubbing liquid in the tube side of the evaporator preheater enters the tube side of the evaporator heater in series. After being heated by the high-temperature hydrolysis waste liquid in the shell of the evaporator heater, it enters the flash tank. The heated scrubbing liquid undergoes flash concentration in the flash tank. The concentrated liquid is separated by the umbrella-shaped baffle and collects at the bottom of the flash tank. When the flash tank level gauge shows 20%, the melt pump inlet valve is opened, and the melt pump is started. Open the flash tank level valve to complete the delivery of concentrated urine; open the flash tank vacuum valve to deliver the washing liquid to the hydraulic ejector to complete the vacuum circulation; adjust the opening of the flash tank vacuum valve to control the flash tank pressure to -30~-40KPa; the flash steam in the flash tank enters the shell side of the evaporator preheater under the vacuum action of the hydraulic ejector, and the flash steam preheats the washing liquid to complete the condensation heat energy recovery. The condensate flows into the dust scrubber by gravity as a circulating absorbent; adjust the washing liquid delivery valve to control the level gauge of the scrubber to be 40%~50%; adjust the flash tank level valve to control the level gauge of the flash tank to be 20%~30%; adjust the hydrolysis waste liquid valve to control the temperature of the flash tank thermometer to be 50-70℃.
[0006] Preferably, the large-particle urea dust washing liquid concentration device based on the cascade utilization of hydrolysis waste heat is located at the large-particle dust scrubber site; the tube side of the evaporator preheats the washing liquid, and the shell side condenses and evaporates flash vapor, achieving full heat recovery through a multi-effect evaporation process. The entire evaporation preheating, heating, and concentration device is integrated and located above the dust scrubber; the condensate in the shell side of the evaporator preheater flows into the dust scrubber by gravity, and the condensate lower liquid pipe is submerged below the liquid surface of the dust scrubber, forming a liquid seal to maintain the vacuum of the flash tank; in addition to transporting the washing liquid and spraying to absorb dust, the washing pump also drives the water jet to maintain the vacuum of the flash tank, realizing the evaporation of the washing liquid under vacuum, enhancing the flash concentration efficiency, and increasing the concentration of the washing liquid.
[0007] This invention breaks through the technical bottlenecks of traditional "direct discharge of hydrolysis waste liquid" and "heating of washing liquid with fresh steam". It maximizes the recovery of waste heat from hydrolysis waste liquid through two-stage heat exchange, reduces steam consumption per ton of urea, and reduces circulating water consumption and external heat loss. Attached Figure Description
[0008] Figure 1 shows a connection diagram of a large-particle urea dust washing liquid concentration device based on the cascade utilization of hydrolysis waste heat according to this utility model.
[0009] Explanation of reference numerals in the attached figures: 1. Washing pump; 2. Evaporator preheater; 3. Evaporator heater; 4. Flash tank; 5. Melting pump; 6. Melting pump inlet valve; 7. Hydraulic jet; 8. Dust scrubber; 9. Scrubber nozzle; 10. Hydrolysis waste liquid valve; 11. Flash tank level valve; 12. Scrubber nozzle valve; 13. Flash tank vacuum valve; 14. Washing liquid delivery valve; 15. Scrubber level gauge; 16. Flash tank pressure gauge; 17. Flash tank level gauge; 18. Flash tank thermometer; 19. Umbrella-shaped baffle. Detailed Implementation
[0010] The present invention will be further described below with reference to Figure 1.
[0011] A large-particle urea dust washing liquid concentration device based on the cascade utilization of hydrolysis waste heat comprises a washing pump 1, an evaporator preheater 2, an evaporator heater 3, a flash tank 4, a melting pump 5, a melting pump inlet valve 6, a hydraulic ejector 7, a dust scrubber 8, a scrubber nozzle 9, a hydrolysis waste liquid valve 10, a flash tank level valve 11, a scrubber nozzle valve 12, a flash tank vacuum valve 13, a washing liquid delivery valve 14, a scrubber level gauge 15, a flash tank pressure gauge 16, a flash tank level gauge 17, and a flash tank thermometer 18. 8. The system consists of an umbrella-shaped baffle 19. The inlet of the washing pump 1 is connected to the dust scrubber 8 via a pipe. The outlet of the washing pump 1 is connected to the scrubber nozzle valve 12, the flash evaporator vacuum valve 13, and the washing liquid delivery valve 14 via pipes. The scrubber nozzle valve 12 is connected to the scrubber nozzle 9 via a pipe. The flash evaporator vacuum valve 13 is connected to the water jet 7 via a pipe. The washing liquid delivery valve 14 is connected to the tube side of the evaporator preheater 2 via a pipe. The tube side of the evaporator preheater 2 is connected to the evaporator heating system via a pipe. The evaporator heater 3 is connected in series in its tube side. The outlet of the tube side of the evaporator heater 3 is connected in series with the flash tank 4 via a pipe. The outlet of the flash tank 4 is connected to the melt pump 5 via the melt pump inlet valve 6 and a pipe. The outlet of the melt pump 5 is connected to the flash tank level valve 11 via a pipe. The steam outlet of the flash tank 4 is connected to the shell of the evaporator preheater 2 via a pipe. The shell of the evaporator preheater 2 is connected to the dust scrubber 8 via a pipe. The outlet of the water jet 7 is connected to the dust scrubber 8 via a pipe. The scrubber nozzle 9 is installed... The hydrolysis waste liquid valve 10 is installed inside the dust scrubber 8 and is connected to the shell of the evaporator heater 3 through a pipe. The shell of the evaporator heater 3 is connected to the dust scrubber 8 through a pipe. The scrubber level gauge 15 is installed at the bottom of the dust scrubber 8. The flash tank pressure gauge 16 is installed at the top of the flash tank 4. The flash tank level gauge 17 and the flash tank thermometer 18 are installed at the bottom of the flash tank 4. The umbrella-shaped baffle 19 inside the flash tank 4 is installed above the tube outlet of the evaporator heater 3.
[0012] When the device is running, open the hydrolysis waste liquid valve 10. The waste liquid enters the dust scrubber 8 through the shell of the evaporator heater 3. When the scrubber level gauge 15 shows 50%, start the scrubbing pump 1 and open the scrubber nozzle valve 12 to send the scrubbing liquid to the scrubber nozzle 9 to complete the spray absorption cycle. Open the scrubbing delivery valve 14 to send the scrubbing liquid to the tube side of the evaporator preheater 2 to complete the scrubbing liquid concentration and delivery. The scrubbing liquid in the tube side of the evaporator preheater 2 enters the tube side of the evaporator heater 3 in series. After being heated by the high-temperature hydrolysis waste liquid in the shell of the evaporator heater 3, it enters the flash tank 4. The heated scrubbing liquid is flash concentrated in the flash tank 4. The concentrated liquid is separated by the umbrella-shaped baffle 19 and collects at the bottom of the flash tank 4. When the flash tank level gauge 17 shows 20%, open the melt pump inlet valve 6 and start the melt pump 5. Open the flash tank level valve 11 to complete the delivery of concentrated urine; open the flash tank vacuum valve 13 to deliver the washing liquid to the hydraulic ejector 7 to complete the vacuum circulation; adjust the opening of the flash tank vacuum valve 13 to control the pressure of the flash tank 16 to -30~-40KPa; the flash steam in the flash tank 4 enters the shell side of the evaporator preheater 2 under the vacuum action of the hydraulic ejector 7, and the flash steam preheats the washing liquid to complete the condensation heat energy recovery. The condensate flows into the dust scrubber 8 by gravity as a circulating absorbent; adjust the washing liquid delivery valve 14 to control the level gauge 15 of the scrubber to display the liquid level at 40%~50%; adjust the flash tank level valve 11 to control the level gauge 17 of the flash tank to display the liquid level at 20%~30%; adjust the hydrolysis waste liquid valve 10 to control the temperature gauge 18 of the flash tank to display 50-70℃.
[0013] The features of this utility model are simple operation, multi-stage efficient utilization of waste heat from hydrolysis waste liquid and closed-loop circulation of washing liquid, reducing the amount of external drainage of the system, significantly reducing steam consumption, circulating water consumption and external heat loss in urea production, and having comprehensive advantages such as low energy consumption, low investment, high integration, high resource utilization and significant environmental benefits.
Claims
1. A large-particle urea dust washing liquid concentration device based on the cascade utilization of hydrolysis waste heat, comprising a washing pump (1), an evaporator preheater (2), an evaporator heater (3), a flash tank (4), a melting pump (5), a melting pump inlet valve (6), a hydraulic jet (7), a dust scrubber (8), a scrubber nozzle (9), a hydrolysis waste liquid valve (10), a flash tank level valve (11), a scrubber nozzle valve (12), a flash tank vacuum valve (13), a washing liquid delivery valve (14), a scrubber level gauge (15), a flash tank pressure gauge (16), a flash tank level gauge (17), a flash tank thermometer (18), and an umbrella-shaped baffle (19), characterized in that, The inlet of the washing pump (1) is connected to the dust scrubber (8) through a pipe. The outlet of the washing pump (1) is connected to the scrubber nozzle valve (12), the flash tank vacuum valve (13), and the washing liquid delivery valve (14) through pipes. The scrubber nozzle valve (12) is connected to the scrubber nozzle (9) through a pipe. The flash tank vacuum valve (13) is connected to the water jet (7) through a pipe. The washing liquid delivery valve (14) is connected to the tube side of the evaporator preheater (2) through a pipe. The tube side of the evaporator preheater (2) is connected in series with the tube side of the evaporator heater (3) through a pipe. The outlet of the tube side of the evaporator heater (3) is connected in series with the flash tank (4) through a pipe. The outlet of the flash tank (4) is connected to the melt pump (5) through the melt pump inlet valve (6) and a pipe. The outlet of the melt pump (5) is connected to the flash tank level valve (11) through a pipe. The steam outlet of the flash tank (4) is connected to the shell of the evaporator preheater (2) through a pipe. The shell of the evaporator preheater (2) is connected to the dust scrubber (8) through a pipe. The outlet of the water jet (7) is connected to the dust scrubber (8) through a pipe. The scrubber nozzle (9) is installed inside the dust scrubber (8). The hydrolysis waste liquid valve (10) is connected to the shell of the evaporator heater (3) through a pipe. The shell of the evaporator heater (3) is connected to the dust scrubber (8). The scrubber level gauge (15) is installed at the bottom of the dust scrubber (8). The flash tank pressure gauge (16) is installed at the top of the flash tank (4). The flash tank level gauge (17) and the flash tank thermometer (18) are installed at the bottom. The umbrella-shaped baffle (19) inside the flash tank (4) is installed above the tube outlet of the evaporator heater (3).