Deep concentrated water low temperature and low pressure full evaporation system and its process
Through the deep brine low-temperature and low-pressure full evaporation system, using single-effect evaporation residual pressure heating and Roots vacuum pump negative pressure technology, the problem of non-condensable gas generated by vacuum evaporation is solved, and high-efficiency and low-energy consumption deep brine treatment is achieved.
Patent Information
- Application Number
- CN202311005356.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-08-10
- Publication Date
- 2025-09-30
- Estimated Expiration
- 2043-08-10
AI Technical Summary
Existing methods for treating deep brine mainly produce non-condensable gases through vacuum evaporation, which results in a complex system and high energy consumption, making it difficult to efficiently treat deep brine.
A deep concentrated water low temperature and low pressure full evaporation system is used, and the single-effect evaporation residual pressure is used to heat the deep concentrated water to 75-85℃. Combined with a Roots vacuum pump to generate negative pressure, it avoids steam condensation and improves evaporation efficiency.
It realizes efficient deep brine treatment without non-condensable gas generation, simplifies the system structure and reduces energy consumption.
Smart Images
Figure FT_1
Abstract
Description
Technical Field
[0001] The present invention relates to a deep-bush water low-temperature and low-pressure full evaporation system and a process thereof, belonging to the technical field of deep-bush water treatment. Background Art
[0002] Evaporation, as a commonly used concentration method, is widely used in the chemical, food, and pharmaceutical industries. Common evaporation methods include single-effect evaporation, multi-effect evaporation, and MVR evaporation. Multi-effect evaporation and MVR evaporation are more economical and widely used due to their low steam consumption. However, when materials need to be concentrated to a higher concentration, single-effect evaporation is still needed to concentrate the materials. Single-effect evaporation produces a large amount of deep concentrated water. Currently, the existing deep concentrated water treatment method is mainly through vacuum evaporation. The steam generated by vacuum evaporation enters the condenser for condensation. This system requires a vacuum pump to continuously remove non-condensable gases. Summary of the Invention
[0003] In order to solve the technical problems existing in the prior art, the present invention provides a deep concentrated water low-temperature and low-pressure full evaporation system and process thereof with simple process, high treatment efficiency and no non-condensable gas generation.
[0004] To achieve the above-mentioned object, the technical solution adopted by the present invention is a deep concentrated water low-temperature low-pressure full evaporation system, comprising a single-effect evaporation concentrated water pipe, a low-pressure steam pipe, a steam condensate pipe, a first evaporator and a second evaporator, wherein the low-pressure steam pipe is installed with a steam main valve and a steam regulating valve, the low-pressure steam pipe is connected to the steam heating coil inlet of the first evaporator and the second evaporator respectively, the steam heating coil inlet of the first evaporator and the second evaporator is further provided with a steam intake control valve, the steam heating coil outlet of the first evaporator and the second evaporator is connected to the steam condensate pipe, the steam heating coil outlet of the first evaporator and the second evaporator is provided with a condensate control valve, the single-effect evaporation concentrated water pipe is connected to the first evaporator and the second evaporator respectively. The concentrated water inlets of the two evaporation tanks are connected, and the concentrated water inlets of the first evaporation tank and the second evaporation tank are respectively provided with concentrated water inlet control valves. The steam outlets of the first evaporation tank and the second evaporation tank are connected to a Roots vacuum pump through a fan connecting pipe, and a steam outlet control valve is installed on the fan connecting pipe. The bottom liquid outlets of the first evaporation tank and the second evaporation tank are respectively connected to the first discharge tank and the second discharge tank through liquid outlet pipes. The bottoms of the first discharge tank and the second discharge tank are provided with liquid outlet pipes, and the liquid outlet valve is installed on the liquid outlet pipes. The liquid outlet control valve is provided on the liquid outlet pipes. The tops of the first discharge tank and the second discharge tank are respectively connected to the fan connecting pipe through vacuum pipes, and the vacuum control valve and the air inlet valve are installed on the vacuum pipes.
[0005] Preferably, the first evaporation tank and the second evaporation tank are further connected to the circulation main pipe through circulation branches, respectively. A circulation control valve is installed on the circulation branch pipe, and a circulation pump is installed on the circulation main pipe. A first circulation flow control valve and a second circulation flow control valve are installed at both ends of the circulation pump, respectively.
[0006] The process of the deep concentrated water low-temperature and low-pressure full evaporation system is operated according to the following steps: During operation, slowly open the concentrated water inlet control valve to introduce the single-effect evaporation concentrated water into the first and second evaporation tanks, open the steam main valve, slightly open the steam regulating valve, open the steam inlet control valve and condensate control valve, start heating the heating coil, open the steam outlet control valve, complete the inspection and preparation work before starting the Roots vacuum pump, and observe the liquid level and temperature of the first and second evaporation tanks;
[0007] When the liquid level reaches above 50%, open the circulation control valve and the first circulation flow control valve, and at the same time slightly open the second circulation flow control valve and start the circulation pump. After confirming that the circulation is normal, fully open the second circulation flow control valve and observe whether the circulation pump is running normally.
[0008] When the evaporation tank temperature reaches above 75°C, start the Roots vacuum pump and adjust the vacuum pump frequency to make the inlet vacuum degree reach -60KPa. Observe the vacuum pump load. If it is not at full load, adjust the amount of concentrated water entering the first and second evaporation tanks and the amount of steam entering the steam heating coil until the vacuum pump is running at full load. Record the adjustment status and any problems.
[0009] If the steam heating coils of the first and second evaporation tanks are fully open, but the vacuum pump is still not at full load, then the vacuum pump load is maintained at the current state;
[0010] When the above work is completed and the operation is stable, perform the first drainage and confirm the evaporation effect. First, open the vacuum control valve to vacuum the first and second discharge tanks. When there is no sound of air flowing at the vacuum control valve, it means that the vacuuming is completed.
[0011] Fully open the liquid outlet control valve, and the liquid enters the first and second discharge tanks. The liquid levels of the first and second discharge tanks are not controlled and are filled until they are full.
[0012] Isolate and break the vacuum, close the liquid outlet control valve and the vacuum control valve to isolate the first discharge tank and the second discharge tank, open the air inlet valve to break the vacuum; drain the liquid until simple evaporation, open the drain valve to drain the liquid, and close the drain valve and the air inlet valve after the drainage is completed.
[0013] Compared with the prior art, the present invention has the following technical effects: the present invention uses the residual pressure of the single-effect evaporation to allow the deep concentrated water from the single-effect evaporation to enter the evaporation tank, and heats it to 75-85°C with low-pressure steam to reduce the corrosion of chloride ions on the stainless steel tubes of the evaporation tank. Then, a roots vacuum pump is used to generate negative pressure to completely extract the evaporated steam. No condensation occurs during the entire process, effectively improving the evaporation and concentration efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION
[0015] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.
[0016] like Figure 1 As shown, the deep concentrated water low-temperature and low-pressure full evaporation system includes a single-effect evaporation concentrated water pipe 1, a low-pressure steam pipe 2, a steam condensate pipe 3, a first evaporation tank 4 and a second evaporation tank 5. The low-pressure steam pipe 2 is installed with a steam main valve 6 and a steam regulating valve 7. The low-pressure steam pipe 2 is connected to the steam heating coil inlet of the first evaporation tank 4 and the second evaporation tank 5 respectively. The steam heating coil inlet of the first evaporation tank 4 and the second evaporation tank 5 is also provided with a steam intake control valve 8. The steam heating coil outlets of the first evaporation tank 4 and the second evaporation tank 5 are connected to the steam condensate pipe 3. The steam heating coil outlets of the first evaporation tank 4 and the second evaporation tank 5 are provided with a condensate control valve 10. The single-effect evaporation concentrated water pipe 1 is connected to the concentrated water inlet of the first evaporation tank 4 and the second evaporation tank 5 respectively. Concentrated water inlet control valves 11 are provided at the first and second evaporation tanks 4 and 5, respectively. The steam outlets of the first and second evaporation tanks 4 and 5 are connected to a Roots vacuum pump 12 via a fan connecting pipe 13, on which a steam outlet control valve 14 is mounted. The bottom liquid outlets of the first and second evaporation tanks 4 and 5 are connected to a first discharge tank 16 and a second discharge tank 17, respectively, via a liquid outlet pipe 15. A liquid outlet pipe 18 is provided at the bottom of the first and second discharge tanks 16 and 17, on which a liquid outlet valve 19 is mounted. A liquid outlet control valve 21 is provided on the liquid outlet pipe 15. The tops of the first and second discharge tanks 16 and 17 are respectively connected to the fan connecting pipe 13 via a vacuum pipe 22, on which a vacuum control valve 23 and an air inlet valve 24 are mounted.
[0017] The first evaporation tank 4 and the second evaporation tank 5 are further connected to the circulation main pipe 26 via circulation branch pipes 25, respectively. A circulation control valve 27 is installed on the circulation branch pipe 25, and a circulation pump 28 is installed on the circulation main pipe 26. The first circulation flow control valve 20 and the second circulation flow control valve 9 are installed at both ends of the circulation pump 28, respectively.
[0018] The process of the deep-concentrate low-temperature low-pressure full evaporation system is as follows: Follow the steps below to operate. During operation, slowly open the concentrate inlet control valve 11 to introduce the single-effect evaporation concentrate into the first evaporator 4 and the second evaporator 5. Open the steam main valve 6, slightly open the steam regulating valve 7, open the steam inlet control valve 8 and the condensate control valve 10, start heating the heating coil, open the steam outlet control valve 14, perform inspections and preparations before starting the Roots vacuum pump 12, and observe the liquid level and temperature of the first evaporator 4 and the second evaporator 5.
[0019] When the liquid level reaches more than 50%, open the circulation control valve 27 and the first circulation flow control valve 20, and at the same time slightly open the second circulation flow control valve 9 and start the circulation pump 28. After confirming that the circulation is normal, fully open the second circulation flow control valve 9 and observe that the circulation pump is operating normally.
[0020] When the evaporation tank temperature reaches above 75°C, start the Roots vacuum pump 28 and adjust the vacuum pump frequency to achieve an inlet vacuum of -60 kPa. Observe the vacuum pump load. If it is not at full load, adjust the amount of concentrated water entering the first evaporation tank 4 and the second evaporation tank 5 and the amount of steam entering the steam heating coil until the vacuum pump is operating at full load. Record the adjustment results and any problems.
[0021] If the steam heating coils of the first evaporation tank 4 and the second evaporation tank 5 are fully open, but the vacuum pump has not yet reached full load, the vacuum pump load is maintained at the current state;
[0022] After the above work is completed and the operation is stable, the first liquid discharge is carried out to confirm the evaporation effect. First, open the vacuum control valve 23 to evacuate the first discharge tank 16 and the second discharge tank 17. When there is no sound of air flowing at the vacuum control valve, the vacuuming is completed.
[0023] Fully open the liquid outlet control valve 21, and the liquid enters the first discharge tank 16 and the second discharge tank 17. The liquid level of the first discharge tank 16 and the second discharge tank 17 is not controlled, and the liquid is filled until it is full.
[0024] Isolate and break the vacuum, close the liquid outlet control valve 21 and the vacuum control valve 23 to isolate the first discharge tank 16 and the second discharge tank 17, open the air inlet valve 24 to break the vacuum; drain the liquid until simple evaporation, open the drain valve 19 to drain the liquid, and close the drain valve 19 and the air inlet valve 24 after the drainage is completed.
[0025] Throughout the entire process, the Roots blower load is generally not adjusted. The vacuum level is adjusted by the steam valve opening and the amount of brine entering. The amount of brine evaporated is determined by the steam extraction rate of the Roots blower. Regular sampling is performed to measure the brine specific gravity, and drainage is determined based on the specific gravity. During regular sampling, the brine TDS is measured. Drainage is only permitted when the TDS exceeds 340,000 mg / L. Alternatively, after sampling, the brine is briefly cooled, and drainage is only permitted when crystallization occurs. After evaporation, the brine reaches a supersaturated state and is directly discharged into a simple evaporator, which can be operated at low heat. A scraper is then used to scrape out the crystallized salt for disposal.
[0026] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of the present invention.
Claims
1. The process of deep concentrated water low temperature and low pressure full evaporation system is characterized by: The deep concentrated water low-temperature and low-pressure full evaporation system includes a single-effect evaporation concentrated water pipe, a low-pressure steam pipe, a steam condensate pipe, a first evaporation tank and a second evaporation tank, and is characterized in that: the low-pressure steam pipe is installed with a steam main valve and a steam regulating valve, the low-pressure steam pipe is connected to the steam heating coil inlet of the first evaporation tank and the second evaporation tank respectively, the steam heating coil inlet of the first evaporation tank and the second evaporation tank is also provided with a steam intake control valve, the steam heating coil outlet of the first evaporation tank and the second evaporation tank is connected to the steam condensate pipe, the steam heating coil outlet of the first evaporation tank and the second evaporation tank is provided with a condensate control valve, the single-effect evaporation concentrated water pipe is connected to the concentrated water of the first evaporation tank and the second evaporation tank respectively. The first and second evaporation tanks are connected to each other in the inlet, the concentrated water inlets of the first evaporation tank and the second evaporation tank are respectively provided with concentrated water inlet control valves, the steam outlets of the first evaporation tank and the second evaporation tank are connected to the Roots vacuum pump through the fan connecting pipe, and the steam outlet control valve is installed on the fan connecting pipe. The bottom liquid outlets of the first evaporation tank and the second evaporation tank are respectively connected to the first discharge tank and the second discharge tank through the liquid outlet pipe, the bottoms of the first discharge tank and the second discharge tank are provided with a liquid outlet pipe, the liquid outlet valve is installed on the liquid outlet pipe, and the liquid outlet control valve is provided on the liquid outlet pipe. The tops of the first discharge tank and the second discharge tank are respectively connected to the fan connecting pipe through vacuum pipes, and the vacuum pipes are installed with a vacuum control valve and an air inlet valve. Specifically, follow the steps below: During operation, slowly open the concentrated water inlet control valve to introduce concentrated water from single-effect evaporation into the first and second evaporation tanks, open the steam main valve, slightly open the steam regulating valve, open the steam inlet control valve and condensate control valve, and start heating the heating coil. Open the steam outlet control valve, complete the inspection and preparation work before starting the Roots vacuum pump, and observe the liquid level and temperature of the first and second evaporation tanks; When the liquid level reaches above 50%, open the circulation control valve and the first circulation flow control valve, and at the same time slightly open the second circulation flow control valve and start the circulation pump. After confirming that the circulation is normal, fully open the second circulation flow control valve and observe whether the circulation pump is running normally. When the evaporation tank temperature reaches above 75°C, start the Roots vacuum pump and adjust the vacuum pump frequency to make the inlet vacuum degree reach -60KPa. Observe the vacuum pump load. If it is not at full load, adjust the amount of concentrated water entering the first and second evaporation tanks and the amount of steam entering the steam heating coil until the vacuum pump is running at full load. Record the adjustment status and any problems. If the steam heating coils of the first and second evaporation tanks are fully open, but the vacuum pump is still not at full load, then the vacuum pump load is maintained at the current state; When the above work is completed and the operation is stable, perform the first drainage and confirm the evaporation effect. First, open the vacuum control valve to vacuum the first and second discharge tanks. When there is no sound of air flowing at the vacuum control valve, it means that the vacuuming is completed. Fully open the liquid outlet control valve, and the liquid enters the first and second discharge tanks. The liquid levels of the first and second discharge tanks are not controlled and are filled until they are full. Isolate and break the vacuum, close the liquid outlet control valve and the vacuum control valve to isolate the first discharge tank and the second discharge tank, open the air inlet valve to break the vacuum; drain the liquid until simple evaporation, open the drain valve to drain the liquid, and close the drain valve and the air inlet valve after the drainage is completed.
2. The process of the deep concentrated water low temperature and low pressure full evaporation system according to claim 1 is characterized in that: The first evaporation tank and the second evaporation tank are further connected to the circulation main pipe through circulation branches, respectively. The circulation main pipe is connected to the single-effect evaporation concentrated water pipe. A circulation control valve is installed on the circulation branch pipe. A circulation pump is installed on the circulation main pipe. A first circulation flow control valve and a second circulation flow control valve are installed at both ends of the circulation pump, respectively.