MTR vacuum concentrator

Abstract

The embodiment of the application provides a kind of MTR vacuum concentrator unit, comprising: power steam system;Solution circulation system and with the secondary steam system of solution circulation system connection;The solution circulation system includes isothermal evaporation tower, and the isothermal evaporation tower is connected with several groups of controllable water distributor components in parallel;The secondary steam system includes vapor-liquid separator, and the vapor-liquid separator upper end is connected with secondary steam balancer, and the vapor-liquid separator lower end is connected with circulating liquid circulation pipe and forced circulation pump;The circulating liquid circulation pipe and forced circulation pump are connected with the isothermal evaporation tower respectively.The application is based on MVR and TVR innovation, provides a kind of more energy-saving equipment and achieves the purpose of cooling, to meet the processing requirements of food and drug industry.

Description

Technical Field

[0001] This invention relates to the field of vacuum concentration, and is a new type of concentration technology equipment that combines mechanical vapor recompression (MVR) and thermal vapor recompression (TVR) technologies to achieve low temperature, energy saving, and condensate recovery, and is suitable for use in the food, pharmaceutical and other industries. Background Technology

[0002] In food and pharmaceutical production, concentration is a process involving phase change and significant latent heat of vaporization. In all industries utilizing concentration technology, the concentration process in food, pharmaceutical, and chemical production is a high-energy-consuming process, especially in the traditional Chinese medicine industry, where steam consumption accounts for over 65% of the total steam usage. There has been a continuous pursuit of more energy-efficient production methods. From single-effect and multi-effect technologies to TVR and MVR, the unit energy consumption of the concentration process has been continuously reduced. Currently, the highest international energy-saving level is achieved using MVR technology, requiring only 40-50 kW / h of electricity to evaporate one ton of water.

[0003] For the production of heat-sensitive materials, traditional Chinese medicine granules, protein peptides, etc., how to carry out efficient, energy-saving, and low-temperature concentration processes to improve product quality is also a problem that needs to be studied.

[0004] Furthermore, many regions in my country, such as Gansu and Guizhou, still suffer from severe water scarcity. While dual-effect heat pumps (TVR) offer advantages like low temperatures, energy efficiency, scale prevention, and relatively low cost, the condensate from the first effect contains about half boiler steam. This boiler-steam-laden condensate is unacceptable for the pharmaceutical and food industries, leading to water waste. Consequently, dual-effect heat pump condensation equipment is difficult to promote in these regions.

[0005] As enterprises develop and production processes demand technological advancements, they also need to be continuously improved to a new level. There is a need to explore a concentration method that is more energy-efficient, operates at a lower temperature than MVR and TVR, and allows for full utilization of condensate. Summary of the Invention

[0006] This application describes an MTR concentrator unit, a novel low-temperature energy-saving system. It is developed by combining MVR and TVR technologies.

[0007] Let me briefly explain the similarities and differences between the two in terms of energy saving. MVR (Mechanical Vapor Recompression) uses mechanical recompression technology to increase the enthalpy of secondary steam in the system before reuse, thus raising the temperature of the secondary steam. TVR (Thermal Vapor Recompression) utilizes steam thermal recompression technology, employing the negative pressure generated by the Laval nozzles of a steam ejector to draw in a portion of the low-temperature, low-pressure secondary steam from the system and continuously reuse this portion. This portion of secondary steam is generated by the heat of the continuously produced mixed steam and only participates in the cycle without being consumed, thereby achieving energy saving. Furthermore, the temperature of the mixed secondary steam decreases in this process, thus lowering the system's heating temperature, allowing the product to be produced at low temperatures throughout the entire process.

[0008] Both methods reuse secondary steam to achieve energy savings. The difference lies in that MVR utilizes all the secondary steam, resulting in a higher temperature after compression; while TVR utilizes only a portion of the secondary steam, leading to a lower mixing temperature after reuse.

[0009] How can we leverage the combined energy-saving advantages of both technologies while achieving cooling to meet the low-temperature and energy-saving process requirements of industries such as pharmaceuticals and food? We will explain this by introducing the research and development project of this invention.

[0010] To address one of the aforementioned technical deficiencies, this application provides an MTR vacuum concentrator unit, comprising: a power steam system, a solution circulation system, and a secondary steam system connected to the solution circulation system; the power steam system includes a centrifugal compressor and a compensating heater for the secondary steam; the solution circulation system includes an isothermal evaporator, with several sets of falling film components connected in parallel to the isothermal evaporator; the secondary steam system includes a vapor-liquid separator, with a steam balancer connected to the upper end of the vapor-liquid separator and a circulating liquid circulation pipe and a forced circulation pump connected to the lower end of the vapor-liquid separator; the circulating liquid circulation pipe and the forced circulation pump are respectively connected to the isothermal evaporator.

[0011] In a preferred embodiment of this application, the isothermal evaporator includes a main body filled with a plurality of evaporator tubes. A controllable water distributor and a circulating water distributor are disposed at the top of the main body. An expansion section is disposed near the upper middle of the main body, and a circulating liquid funnel is disposed at the bottom of the main body. In another preferred embodiment of this application, the falling film assembly includes a falling film variable frequency pump. The two ends of the falling film variable frequency pump are respectively connected to a circulating water distributor and a dilute liquid tank, which is located at the bottom of the isothermal evaporator.

[0012] As a preferred embodiment of this application, a forced circulation pump is connected at one end to the bottom of the vapor-liquid separator and at the other end to the circulating water distributor.

[0013] As a preferred embodiment of this application, the unit further includes a steam jet heat pump, which is provided with a high-pressure injection port, a low-pressure suction port and a mixed steam outlet. The high-pressure injection port is connected to the compressor outlet of the centrifugal compressor; the low-pressure suction port is connected to the secondary steam balancer; and the mixed steam outlet is connected to the evaporator inlet of the expansion section.

[0014] As a preferred embodiment of this application, the centrifugal compressor is further provided with a compressor inlet, which is connected to a secondary steam compensation heater. The secondary steam compensation heater is connected to a steam balancer, a live steam inlet, and a steam trap, respectively. A steam regulating valve is provided at the live steam inlet.

[0015] As a preferred embodiment of this application, the isothermal evaporator is connected to a condensate outlet at the lower middle part.

[0016] As a preferred embodiment of this application, the upper and lower parts of the isothermal evaporator are each connected to a non-condensable gas discharge pipe, and the free ends of the two non-condensable gas discharge pipes merge and are connected to a pressure drainer.

[0017] The MTR vacuum concentrator unit provided in this application combines mechanical vapor recompression (MVR) and thermal vapor recompression (TVR) technologies to create a novel low-temperature, energy-saving, and condensate-recoverable concentrator suitable for the food and pharmaceutical industries. It includes: a solution circulation system and a secondary steam system connected to the solution circulation system; the solution circulation system includes an isothermal evaporator with several sets of falling film assemblies connected in parallel; each falling film assembly includes a circulating water distributor and a controllable water distributor, the circulating water distributor being connected to a forced circulation pump and the evaporator tubes, and the controllable water distributor being connected to a falling film variable frequency pump and the evaporator tubes; the secondary steam system includes a vapor-liquid separator, the upper end of which is connected to a steam balancer, and the lower end of which is connected to a circulating liquid circulation pipe and a forced circulation pump; the circulating liquid circulation pipe and the forced circulation pump are respectively connected to the isothermal evaporator. This application innovates upon MVR and TVR, providing a more energy-efficient device that achieves cooling to meet the processing requirements of the food and pharmaceutical industries. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0019] Figure 1 This is a schematic diagram of the structure provided for an embodiment of this application;

[0020] Figure 2This is a top view of an embodiment of this application.

[0021] Centrifugal compressor 1, compressor inlet 2, compressor outlet 3, steam jet heat pump 4, high-pressure jet port 5, low-pressure suction port 6, mixed steam outlet 7, isothermal evaporator tower 8, evaporator inlet 9, expansion section 10, evaporator tubes 11, non-condensable gas discharge pipe 12, pressure drain 13, condensate outlet 14, falling film variable frequency regulating pump 15, controllable water distributor 16, dilute liquid tank 17, forced circulation pump 18, circulating water distributor 19, circulating liquid funnel 20, circulating liquid circulation pipe 21, isobaric steam suction port 22, centrifugal jet port 23, vapor-liquid separator 24, steam balancer 25, compensating heater 26, live steam inlet 27, steam regulating valve 28, steam trap 29, flash defoamer 30, paste collection switching valve 31, frequency converter 32. Detailed Implementation

[0022] To make the technical solutions and advantages of the embodiments of this application clearer, the exemplary embodiments of this application will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not an exhaustive list of all embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other.

[0023] In the process of developing this application, the inventors discovered that concentration technology for the food and pharmaceutical manufacturing industry needs further optimization.

[0024] To address the aforementioned issues, this application provides an MTR vacuum concentrator unit, such as... Figure 1 Figure 2 As shown, the embodiments of this application include: a solution circulation system and a secondary steam system connected to the solution circulation system; the solution circulation system includes an isothermal evaporator 8, and several sets of falling film assemblies are connected in parallel to the isothermal evaporator 8. The falling film assembly includes a falling film variable frequency regulating pump 15, and the two ends of the falling film variable frequency regulating pump 15 are respectively connected to a controllable water distributor 16 and a dilute liquid tank 17, and the dilute liquid tank 17 is located at the bottom of the isothermal evaporator 8.

[0025] The secondary steam system includes a vapor-liquid separator 24, with a steam balancer 25 connected to its upper end and a circulating liquid circulation pipe 21 and a forced circulation pump 18 connected to its lower end. The circulating liquid circulation pipe 21 and the forced circulation pump 18 are respectively connected to the isothermal evaporator 8. One end of the forced circulation pump 18 is connected to the bottom of the vapor-liquid separator 24, and the other end is connected to the circulating water distributor 19. A flash defoamer 30 is installed on the vapor-liquid separator 24. A paste collection switching valve 31 is installed on the pipeline connecting the forced circulation pump 18 and the isothermal evaporator 8.

[0026] The isothermal evaporator 8 includes a main body filled with a plurality of evaporator tubes 11. A controllable water distributor 16 and a circulating water distributor 19 are provided at the top of the main body. An expansion section 10 is provided at the upper middle part of the main body. A circulating liquid funnel 20 is provided at the bottom of the main body.

[0027] The isothermal evaporator 8 is connected to the condensate outlet 14 at the lower middle part. Both the upper and lower parts of the isothermal evaporator 8 are connected to a non-condensable gas discharge pipe 12. The free ends of the two non-condensable gas discharge pipes 12 converge and are connected to a pressure drain device 13.

[0028] The circulating liquid funnel 20 is connected to the isobaric steam inlet 22. The isobaric steam inlet 22 is connected to the lower part of the vapor-liquid separator 24 through the circulating liquid circulation pipe 21. The centrifugal injection port 23 is provided at the connection end between the circulating liquid circulation pipe 21 and the vapor-liquid separator 24.

[0029] The unit also includes a steam jet heat pump 4, which is provided with a high-pressure injection port 5, a low-pressure suction port 6 and a mixed steam outlet 7. The mixed steam outlet 7 is connected to the evaporator inlet 9 of the expansion section 10. The high-pressure injection port 5 is connected to the compressor outlet 3 of the centrifugal compressor 1, and the low-pressure suction port is connected to the steam balancer 25.

[0030] The centrifugal compressor 1 is also provided with a compressor inlet 2, which is connected to a compensating heater 26. The arc length heater is connected to a steam balancer 25, a live steam inlet 27 and a steam trap 29 respectively. A steam regulating valve 28 is provided at the live steam inlet 27.

[0031] The MTR concentrator unit of this invention is a novel low-temperature energy-saving system. This invention is developed by combining MVR and TVR technologies.

[0032] As a preferred embodiment of this application, the solution circulation system includes: six falling film variable frequency regulating pumps 15 (1-6), which are connected upward to controllable water distributors 16 (1-6) and then flow into dilute liquid tanks 17 (1-6); a forced circulation pump 18, which is connected upward to a circulation water distributor 19 and then flows downward into a concentrated liquid funnel 20; the concentrated liquid funnel 20 is connected to a concentrated liquid circulation pipe 21; an isobaric vapor outlet 22 is arranged on the concentrated liquid circulation pipe 21 (the saturated vapor pressure of the dilute liquid and the concentrated liquid is the same); and the concentrated liquid circulation pipe 21 finally enters the vapor-liquid separator 24 through a centrifugal jet port 23.

[0033] Secondary steam system: The secondary steam separated from the vapor-liquid separator 24 enters the steam balancer 25, and part of it enters the low-pressure suction port 6 of the steam jet heat pump 4, where it mixes with the high-temperature steam from the high-pressure jet port 5, and then exits from the mixed steam outlet 7, entering the isothermal evaporator 8; part of the secondary steam in the steam balancer 25 enters the preheater 26, where it exchanges heat with the high-temperature liquid at the countercurrent extractor outlet 27 connected to the upper end of the preheater 26, and the secondary steam condensate flows to the pressure drainer 28; the secondary steam that has not yet reached the set temperature enters the temperature compensation heater 29, which is connected to the live steam inlet 30, and the live steam flow rate is controlled by the steam regulating valve 31; the secondary steam that has reached the set temperature enters the compressor 1 for reuse. The falling film variable frequency regulating pump 15 is connected to the frequency converter 32.

[0034] The specific principles of this application are as follows:

[0035] The working principle of this invention will be explained using the configuration in this MTR R&D project. In this project, the concentration temperature is set to the temperature of the secondary steam. For example, using an SFV2-80 / 92 compressor, the inlet temperature is 80℃, which is the compressor's rated inlet temperature, and the rated steam temperature at the compressor outlet is 92℃. A steam ejector with a suitable ejector coefficient is selected based on the compressor flow rate for the R&D project; the evaporation system employs falling film concentration.

[0036] (i) Heating: Since the secondary steam generated by the concentration system is at a low temperature, the live steam in the compensation heater is used to heat the secondary steam to the rated inlet temperature of the compressor before it enters the compressor. The secondary steam is heated and pressurized by the compressor and then provided to the system for reuse.

[0037] (ii) Cooling and expansion: The high-temperature and high-pressure gas discharged from the compressor enters the inlet of the steam ejector, and under the action of the Laval nozzle, it draws in secondary steam and expands the volume, so as to achieve the effect of reusing the latent heat of vaporization of secondary steam.

[0038] (III) Heat exchange: The mixed steam from the steam ejector outlet enters the isothermal evaporation tower. The heat exchange temperature difference is designed to be small based on the process requirements of falling film concentration. The heat exchange area of ​​the heater is designed according to the evaporation temperature and other conditions after falling film concentration evaporation.

[0039] (iv) Reuse of secondary steam: After heat exchange of the mixed steam in the falling film condenser, low-temperature saturated secondary steam is generated. It is divided into two paths in the steam balancer. One path is drawn in according to the ejector suction ratio, and the other path is drawn in by the compressor at the rated compression ratio.

[0040] (V) Energy-Saving Principle Analysis: High-temperature, high-pressure gas from the compressor outlet enters the steam jet pump. Under the high negative pressure generated at the Laval nozzle, it additionally absorbs low-temperature, low-pressure gas from the vapor-liquid separator. The absorbed low-temperature gas mixes with the high-temperature gas from the compressor within the ejector, producing a mixed gas. This mixed gas fully participates in the heat exchange process of concentration. The low-temperature, low-pressure steam absorbed by the ejector acts only as a carrier in the concentration process, continuously participating in the cycle without being consumed. The remaining secondary steam is used by the compressor, and its combination with the steam jet heat pump produces a greater evaporation effect. By reusing the latent heat of the secondary steam through the steam jet heat pump, the efficiency of the original MVR unit is improved. (The live steam in the compensation heater heats the secondary steam before it enters the compressor; this portion of heat is relatively small and is roughly negligible in the calculation.)

[0041] (vi) Generation of Low-Temperature and Usable Condensate: The steam ejector utilizes the high-temperature, high-pressure motive steam from the compressor to draw in and mix the low-temperature secondary steam from the vapor-liquid separator, forming a low-temperature heat source that serves as the heating source for the heat exchanger. During heat exchange, the condensate is cooled to a clean, reusable source free of boiler water. This is particularly suitable for use in the pharmaceutical and food industries.

[0042] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0044] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0045] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0046] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. An MTR vacuum concentrator unit, characterized in that, include: The system comprises a power steam system, a solution circulation system, and a secondary steam system connected to the solution circulation system; the power steam system includes a centrifugal compressor and a compensating heater for the secondary steam; the solution circulation system includes an isothermal evaporator with several sets of falling film evaporators connected in parallel; the secondary steam system includes a vapor-liquid separator with a steam balancer connected to its upper end and a circulating liquid circulation pipe and a forced circulation pump connected to its lower end; the circulating liquid circulation pipe and the forced circulation pump are respectively connected to the isothermal evaporator. The isothermal evaporator includes a main body filled with several evaporator tubes, a controllable water distributor and a circulating water distributor are provided at the top of the main body; an expansion section is provided at the upper middle part of the main body, and a circulating liquid funnel is provided at the bottom of the main body; The unit also includes a steam jet heat pump, which is equipped with a high-pressure injection port, a low-pressure suction port and a mixed steam outlet. The high-pressure injection port is connected to the compressor outlet of the centrifugal compressor, the low-pressure suction port is connected to the steam balancer, and the mixed steam outlet is connected to the evaporator inlet of the expansion section.

2. The MTR vacuum concentrator unit according to claim 1, characterized in that, The falling film assembly includes a falling film variable frequency regulating pump, which is connected at both ends to a circulating water distributor and a dilute liquid tank, respectively. The dilute liquid tank is located at the bottom of the isothermal evaporation tower.

3. The MTR vacuum concentrator unit according to claim 1, characterized in that, A forced circulation pump is connected at one end to the bottom of the vapor-liquid separator and at the other end to the circulating water distributor.

4. The MTR vacuum concentrator unit according to claim 1, characterized in that, The centrifugal compressor is also provided with a compressor inlet, which is connected to a compensation heater. The compensation heater is connected to a steam balancer, a live steam inlet, and a steam trap. A steam regulating valve is provided at the live steam inlet.

5. The MTR vacuum concentrator unit according to claim 1, characterized in that, The isothermal evaporation tower is connected to a condensate outlet at the lower middle part.

6. The MTR vacuum concentrator unit according to claim 1, characterized in that, The isothermal evaporator is connected to a non-condensable gas discharge pipe at both the top and bottom. The free ends of the two non-condensable gas discharge pipes merge and are connected to a pressure drain.

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