Intelligent energy-saving device for phosphoric acid evaporation concentration
The closed-loop system, consisting of a two-stage falling film evaporation and concentration module and a steam purification and regeneration module, solves the problems of high energy consumption and system instability in phosphoric acid evaporation and concentration devices, achieving a highly efficient, energy-saving, and environmentally friendly phosphoric acid concentration process.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN SUNEVAP TECH
- Filing Date
- 2025-07-24
- Publication Date
- 2026-07-21
AI Technical Summary
Existing phosphoric acid evaporation and concentration units consume huge amounts of energy in chemical processes, have low thermal efficiency, insufficient utilization of secondary steam waste heat, poor system stability, are prone to clogging, operate in harsh environments, and are affected by volatile acid gases.
The system employs a two-stage falling film evaporation and concentration module, a steam purification and regeneration module, and an intelligent control module to form a closed-loop system. Combined with a shell-and-tube preheater and a steam purification and regeneration device, it achieves efficient utilization of steam waste heat and automated control, prevents equipment blockage, reduces energy consumption, and improves system stability.
It significantly reduces energy consumption by more than 40%, reduces equipment footprint by 30%, increases automation, reduces pollutant emissions, and ensures more stable operation, meeting the requirements of sustainable development.
Smart Images
Figure CN224523972U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of chemical engineering technology, and in particular to an intelligent energy-saving device for phosphoric acid evaporation and concentration. Background Technology
[0002] Phosphoric acid, as a fundamental chemical raw material, plays an irreplaceable role in various fields such as industry, agriculture, food, medicine, and electronics due to its unique chemical properties and multifunctionality. In agriculture, its application is mainly in the production of phosphate fertilizers, as it is an indispensable nutrient element for plant growth. Food-grade phosphoric acid (purity ≥85%) is an important component in food additives, primarily used as an acidity regulator and preservative. In the industrial sector, phosphoric acid is used in metal processing, cleaning agent production, and chemical synthesis. In the pharmaceutical field, phosphate buffer solutions are widely used in pharmaceutical preparations to adjust pH values and maintain drug stability. In daily chemical products, phosphoric acid... Salts, as chelating agents and pH adjusters, are widely used in toothpaste, shampoo, and skin care products. Phosphoric acid and its derivatives also play an important role in environmental protection. In water treatment, phosphates, as corrosion inhibitors and scale inhibitors, can effectively prevent scaling and corrosion in pipes and boilers, extending equipment lifespan. In wastewater treatment, phosphates remove heavy metal ions through chemical precipitation, reducing the pollution of industrial wastewater to the environment. Phosphoric acid evaporation and concentration, as a key process in wet-process phosphoric acid production, has significant industrial value and economic significance. Different application fields have strict technical requirements for phosphoric acid concentration, and evaporation and concentration are essential to achieving these requirements. In the wet-process phosphoric acid production process, the initial concentration of dilute phosphoric acid is typically in the range of 20%–30% P2O5. Through evaporation and concentration, the concentration can be increased to 50%–54% commercial-grade phosphoric acid or even higher concentration industrial-grade phosphoric acid (72%–75% P2O5). This increase in concentration multiplies the value of the product per unit volume. In the transportation process, the concentrated high-concentration phosphoric acid significantly reduces logistics costs, and the amount of the same effective component transported can be reduced by more than 60%. As a key link connecting upstream production and downstream applications, the significance of phosphoric acid evaporation and concentration has transcended a simple process and has become a core factor affecting the economic benefits, product quality, resource utilization, and technological level of the phosphoric acid chemical industry. Therefore, an intelligent and energy-saving device for phosphoric acid evaporation and concentration is needed.
[0003] Existing intelligent energy-saving devices for phosphoric acid evaporation and concentration use conventional multi-effect evaporation to produce live steam during chemical processing, resulting in huge energy consumption. In addition, they have low thermal efficiency, with a secondary steam waste heat utilization rate of less than 60%, poor system stability, and are prone to blockage during the concentration process. Furthermore, the operating environment is harsh, with volatile acid gases affecting the working environment. Utility Model Content
[0004] The purpose of this invention is to provide an intelligent energy-saving device for phosphoric acid evaporation and concentration, in order to solve the problems mentioned in the background art regarding the existing intelligent energy-saving devices for phosphoric acid evaporation and concentration. In chemical processes, the evaporation technology uses conventional multi-effect evaporation to generate steam, which consumes a lot of energy. In addition, the thermal efficiency is low, the utilization rate of secondary steam waste heat is less than 60%, and the system stability is poor. Blockage is prone to occur during the concentration process. At the same time, the operating environment is harsh, and volatile acid gases affect the working environment.
[0005] To achieve the above objectives, this utility model provides the following technical solution: an intelligent energy-saving device for phosphoric acid evaporation and concentration, comprising a feeding module, the feeding module including a raw material tank, the outlet pipe of the raw material tank being connected to a feeding pump, the outlet pipe of the feeding pump being connected to a three-stage preheating module, the three-stage preheating module being connected to a two-stage falling film evaporation and concentration module, the two-stage falling film evaporation and concentration module being connected to a steam purification and regeneration module, the steam purification and regeneration module being connected to a discharge module, and the two-stage falling film evaporation and concentration module being connected to an intelligent control module.
[0006] Preferably, the three-stage preheating module includes a secondary steam condensate preheater, the output pipe of which is connected to a non-condensable gas preheater, and the output pipe of which is connected to a live steam preheater.
[0007] Preferably, the dual-stage falling film evaporation and concentration module includes a distilled water pump, the input pipe of which is connected to a distilled water tank, the inlet pipe of which is connected to a dual-stage integrated falling film evaporator, the output pipe of which is connected to a falling film circulation pump, and the output pipe of which is connected to a falling film separator.
[0008] Preferably, the discharge module includes a discharge pump, and the inlet pipe of the discharge pump is connected to a two-stage integrated falling film evaporator.
[0009] Preferably, the steam purification and regeneration module includes a scrubbing gas circulation pump, the output end pipe of the scrubbing gas circulation pump is connected to a scrubbing tower, the output end pipe of the scrubbing tower is connected to a compressor unit, and the output end pipe of the scrubbing tower is connected to a liquid collection pump.
[0010] Preferably, the intelligent control module includes a non-condensable gas cooler, and the output pipe of the non-condensable gas cooler is connected to a vacuum pump.
[0011] Preferably, the output pipe of the feed pump is connected to a secondary steam condensate preheater, the output pipe of the live steam preheater is connected to a two-stage integrated falling film evaporator, the output pipe of the falling film separator is connected to a gas scrubbing tower, and the output pipe of the two-stage integrated falling film evaporator is connected to a discharge pump.
[0012] Compared with existing technologies, the beneficial effects of this utility model are as follows: Through the setup of a feeding module, a three-stage preheating module, a two-stage falling film evaporation and concentration module, a steam purification and regeneration module, a discharge module, and an intelligent control module, with special alloy pipes connecting each module to form a closed-loop system, the combined effect of these modules achieves energy saving, environmental protection, simple operation, and high automation. This utility model is the first to apply a two-stage integrated falling film evaporator to the field of phosphoric acid concentration. The innovatively developed tube-and-shell preheater effectively prevents equipment blockage. Furthermore, the gas washing unit of the steam purification and regeneration module significantly reduces the risk of compressor corrosion by purifying acid mist, while also reducing energy consumption. Compared with traditional single-effect / multi-effect processes, it saves more than 40% in energy. In addition, the device occupies a small area, and the modular design saves approximately 30% of space. Moreover, it achieves adaptive control based on concentration feedback. The evaporation control algorithm establishes a comprehensive intelligent monitoring system, improving operational reliability and achieving a high degree of automation. It enables intelligent control throughout the entire process, supports remote operation and maintenance platform interfaces, and provides automatic protection against abnormal operating conditions. Compared to existing technologies, this solution represents a significant technological advancement. It specifically addresses the high energy consumption issue in the phosphoric acid concentration process by proposing an innovative solution. Employing secondary steam compression as a circulating heat source reduces boiler dependence, lowers energy consumption, reduces pollutants, and minimizes environmental pollution, making it more energy-efficient and environmentally friendly. Compared to indirect evaporation concentration processes, it has lower equipment investment costs and lower operating energy consumption. Compared to compressors with lower temperature rise, it operates more stably. The device has a simple process flow, is easy to implement, highly automated, and has low operating costs, meeting sustainable development requirements. It possesses outstanding practicality and economic efficiency and can be widely applied in actual industrial production processes. Attached Figure Description
[0013] Figure 1 This is a schematic diagram of the structure of an intelligent energy-saving device for phosphoric acid evaporation and concentration disclosed in this embodiment.
[0014] In the diagram: 1. Raw material tank; 2. Feed pump; 3. Secondary steam condensate preheater; 4. Non-condensable gas preheater; 5. Live steam preheater; 6. Distilled water pump; 7. Distilled water tank; 8. Two-stage integrated falling film evaporator; 9. Falling film circulation pump; 10. Falling film separator; 11. Discharge pump; 12. Wash gas circulation pump; 13. Wash gas tower; 14. Compressor unit; 15. Liquid collection pump; 16. Non-condensable gas cooler; 17. Vacuum pump. Detailed Implementation
[0015] 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.
[0016] Please see Figure 1 This utility model provides a technical solution: an intelligent energy-saving device for phosphoric acid evaporation and concentration, including a feeding module, which includes a raw material tank 1. The outlet pipe of the raw material tank 1 is connected to a feeding pump 2. The outlet pipe of the feeding pump 2 is connected to a three-stage preheating module. The three-stage preheating module is connected to a two-stage falling film evaporation and concentration module. The two-stage falling film evaporation and concentration module is connected to a steam purification and regeneration module. The steam purification and regeneration module is connected to a discharge module. The two-stage falling film evaporation and concentration module is connected to an intelligent control module.
[0017] Furthermore, the three-stage preheating module includes a secondary steam condensate preheater 3, with a non-condensable gas preheater 4 connected to the output pipe of the secondary steam condensate preheater 3, and a live steam preheater 5 connected to the output pipe of the non-condensable gas preheater 4. Through the arrangement of the secondary steam condensate preheater 3, the non-condensable gas preheater 4, and the live steam preheater 5, the waste heat of the secondary steam condensate and non-condensable gas can be fully recovered and utilized during use. In addition, the three-stage preheating module adopts a shell-and-tube preheater with multiple tube bundles densely arranged, which can achieve a high heat transfer area per unit volume, a long maintenance cycle, and temporary blocking of damaged single tubes without affecting the overall operation, resulting in low replacement costs.
[0018] Furthermore, the two-stage falling film evaporation and concentration module includes a distilled water pump 6, an input pipe of which is connected to a distilled water tank 7, an inlet pipe of which is connected to a two-stage integrated falling film evaporator 8, an output pipe of which is connected to a falling film circulation pump 9, and an output pipe of which is connected to a falling film separator 10. Through the arrangement of the distilled water pump 6, distilled water tank 7, two-stage integrated falling film evaporator 8, falling film circulation pump 9, and falling film separator 10, the two-stage falling film evaporation and concentration module, with its integrated structure, allows for initial concentration in the first stage and high-concentration evaporation in the second stage, avoiding single-stage overload and improving overall efficiency. The integration of both stages within a single housing reduces pipe connection points, lowers leakage risk, and lowers maintenance costs by 20%–40% compared to traditional split-type modules. The overall structure also saves approximately 35% of floor space.
[0019] Furthermore, the discharge module includes a discharge pump 11, the inlet pipe of which is connected to a two-stage integrated falling film evaporator 8. Through the setup of the two-stage integrated falling film evaporator 8 and the discharge pump 11, during use, when the phosphoric acid concentration of the liquid in the lower body of the two-stage integrated falling film evaporator 8 reaches more than 30%, the discharge pump 11 will extract it and push it out of the boundary area.
[0020] Furthermore, the steam purification and regeneration module includes a gas scrubbing pump 12, the output pipe of which is connected to a gas scrubbing tower 13, the output pipe of which is connected to a compressor unit 14, and the output pipe of which is connected to a liquid collection pump 15. By setting up the gas scrubbing pump 12, the gas scrubbing tower 13, the compressor unit 14, and the liquid collection pump 15, the consumption of live steam can be reduced, the operating cost can be lowered, and the gas scrubbing method can remove acid gas and salt droplets that are harmful to the compressor unit 14 from the secondary steam. The steam after gas scrubbing can be directly compressed, which greatly reduces the requirements for the temperature rise of the compressor unit 14, thereby not only reducing the operating energy consumption but also reducing the heat exchange area.
[0021] Furthermore, the intelligent control module includes a non-condensable gas cooler 16, and the output pipe of the non-condensable gas cooler 16 is connected to a vacuum pump 17. Through the setup of the non-condensable gas cooler 16 and the vacuum pump 17, under the action of the safety operating system built into the PLC control system, damage to product quality and damage to important components during production can be prevented. It has a high degree of automation and can achieve fully automatic operation with very little manual operation.
[0022] Furthermore, the output pipe of the feed pump 2 is connected to the secondary steam condensate preheater 3, the output pipe of the live steam preheater 5 is connected to the dual-stage integrated falling film evaporator 8, the output pipe of the falling film separator 10 is connected to the scrubbing tower 13, and the output pipe of the dual-stage integrated falling film evaporator 8 is connected to the discharge pump 11. Through the arrangement of the feed pump 2, the secondary steam condensate preheater 3, the live steam preheater 5, the dual-stage integrated falling film evaporator 8, the falling film separator 10, the discharge pump 11, and the scrubbing tower 13, each module can be connected through special alloy pipes to form a closed-loop system.
[0023] Working Principle: The raw material from raw material tank 1 is preheated by the feed pump 2 into the secondary steam condensate preheater 3, non-condensable gas preheater 4, and live steam preheater 5. After preheating, the raw material enters the two-stage integrated falling film evaporator 8. Driven by the circulation of the falling film circulation pump 9, the solution circulates within the two-stage integrated falling film evaporator 8 and continuously exchanges heat with the hot side for evaporation. The generated secondary steam escapes to the falling film separator 10 through the connecting pipe, then passes through the gas scrubbing tower 13, and then enters the compressor unit 14. The heated and pressurized secondary steam returns to the hot side of the two-stage integrated falling film evaporator 8 as a heating source. After heat utilization, it is liquefied into secondary steam condensate and flows into the distillation water tank 7. The secondary steam condensate inside the distillation water tank 7 is drawn out by the distillation water pump 6 and pumped into the secondary steam condensate preheater 3 to exchange heat with the raw material for preheating. When the phosphoric acid concentration of the liquid in the lower part of the two-stage integrated falling film evaporator 8 reaches a certain level, the condensate is heated to a certain level. When the concentration reaches 30% or more, the discharge pump 11 will extract it and push it out of the boundary area. The liquid may contain a small amount of dissolved air, or there may be a small amount of air leakage in the device. Non-condensable gas will be formed during the evaporation process. After being initially cooled by the non-condensable gas cooler 16 with circulating cooling water, it will be pumped out of the system boundary area by the vacuum pump 17 which adjusts the vacuum of the system. By adopting the above technical solution, the vacuum of the system can be controlled to the set value by the interlocking of the vacuum pump 17, pressure sensor, and regulating valve. The feeding can be automatically controlled by the liquid level interlocking feed pump 2 frequency converter of the two-stage integrated falling film evaporator 8. The whole automatic control system can achieve a high degree of automation. In this embodiment, the condensate generated by the compressor unit 14 during operation will flow into the compressor condensate pipe and be connected to the inlet of the condensate pump 15. The condensate pump 15 will pump the compressor condensate into the distilled water tank 7 to participate in the subsequent preheating and discharge.
[0024] 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. An intelligent energy-saving device for phosphoric acid evaporation and concentration, comprising a feeding module, characterized in that: The feeding module includes a raw material tank (1), the outlet pipe of the raw material tank (1) is connected to a feeding pump (2), the outlet pipe of the feeding pump (2) is connected to a three-stage preheating module, the three-stage preheating module is connected to a two-stage falling film evaporation and concentration module, the two-stage falling film evaporation and concentration module is connected to a steam purification and regeneration module, the steam purification and regeneration module is connected to a discharge module, and the two-stage falling film evaporation and concentration module is connected to an intelligent control module. The three-stage preheating module includes a secondary steam condensate preheater (3), the output end of which is connected to a non-condensable gas preheater (4), and the output end of which is connected to a live steam preheater (5). The dual-stage falling film evaporation and concentration module includes a distilled water pump (6), the input end of which is connected to a distilled water tank (7), the inlet end of which is connected to a dual-stage integrated falling film evaporator (8), the output end of which is connected to a falling film circulation pump (9), and the output end of which is connected to a falling film separator (10).
2. The intelligent energy-saving device for phosphoric acid evaporation and concentration according to claim 1, characterized in that: The discharge module includes a discharge pump (11), and the inlet pipe of the discharge pump (11) is connected to a two-stage integrated falling film evaporator (8).
3. The intelligent energy-saving device for phosphoric acid evaporation and concentration according to claim 1, characterized in that: The steam purification and regeneration module includes a gas washing circulation pump (12), the output end of the gas washing circulation pump (12) is connected to a gas washing tower (13), the output end of the gas washing tower (13) is connected to a compressor unit (14), and the output end of the gas washing tower (13) is connected to a liquid collection pump (15).
4. The intelligent energy-saving device for phosphoric acid evaporation and concentration according to claim 1, characterized in that: The intelligent control module includes a non-condensable gas cooler (16), and the output end of the non-condensable gas cooler (16) is connected to a vacuum pump (17).
5. The intelligent energy-saving device for phosphoric acid evaporation and concentration according to claim 1, characterized in that: The output pipe of the feed pump (2) is connected to a secondary steam condensate preheater (3), the output pipe of the live steam preheater (5) is connected to a two-stage integrated falling film evaporator (8), the output pipe of the falling film separator (10) is connected to a gas scrubbing tower (13), and the output pipe of the two-stage integrated falling film evaporator (8) is connected to a discharge pump (11).