MVR type drying crystallization system

Abstract

The utility model relates to the technical field of evaporation energy-saving and environment-friendly facilities, in particular to an MVR (Mechanical Vapor Recompression) type drying and crystallizing system, which comprises an evaporation unit comprising at least two groups of evaporation chambers arranged in parallel, and each group of evaporation chamber is provided with a to-be-treated liquid inlet and a heating module for heating the to-be-treated liquid until the to-be-treated liquid is boiled and evaporated; the steam circulation unit comprises a compressor used for compressing steam, and a steam outflow channel and a steam inflow channel are connected between the compressor and each set of evaporation chambers in the steam circulation direction; wherein at least two groups of evaporation chambers are provided with waste discharge ports which are not opened for discharging at the same time. The multiple sets of evaporation chambers are arranged in parallel, crystals are discharged in a staggered mode, insufficient steam supply of an inlet of the compressor is avoided, the problem that traditional steam type crystallization equipment with live steam as energy is high in energy consumption is solved, and the problems that when an MVR compressor is used in drying crystallization equipment, live steam is needed for assistance, and frequent starting and stopping are needed are also solved.

Description

Technical Field

[0001] This utility model relates to the field of evaporation energy saving and environmental protection facilities technology, and in particular to an MVR drying and crystallization system. Background Technology

[0002] Existing drying and crystallization equipment uses steam for heating, consuming approximately 1.2 tons of steam to process 1 ton of waste liquid, resulting in excessively high overall treatment costs. MVR compressors are mostly used in the concentration industry, requiring a stable steam flow rate at the compressor inlet for stable operation. However, drying and crystallization equipment operates on a batch processing basis, with the process divided into three stages: heating, evaporation, and drying.

[0003] Currently, when MVR is used in crystallization equipment, the amount of steam during the preheating and final crystallization drying stages is too small, which does not meet the compressor's air intake requirements. Live steam is needed as an energy supplement for these two stages, and the overall processing cost is not low. Moreover, the compressor will start and stop frequently, reducing its service life. Utility Model Content

[0004] In this section, as well as in the abstract and title of this application, some simplifications or omissions may be made to avoid obscuring the purpose of this section, the abstract, and the title of this application. Such simplifications or omissions shall not be used to limit the scope of this utility model.

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide an MVR-type drying and crystallization system.

[0006] To achieve the above objectives, this utility model adopts the following technical solution: an MVR-type drying and crystallization system, comprising,

[0007] An evaporation unit comprising at least two sets of evaporation chambers arranged in parallel, each set of evaporation chambers having an inlet for the liquid to be treated and a heating module for heating the liquid to be treated to boiling point for evaporation; and,

[0008] A steam circulation unit includes a compressor for compressing steam, wherein each evaporation chamber is connected to a steam outflow channel and a steam inflow channel in the direction of steam flow.

[0009] Among them, at least two sets of the evaporation chambers have waste discharge ports that are opened at different times.

[0010] In a preferred embodiment of the drying and crystallization system described in this utility model, the heating module includes an interlayer that allows a heat medium to pass through it, the interlayer being disposed on the outer wall of the evaporator chamber;

[0011] The interlayer is connected to the compressor outlet via a steam inflow channel.

[0012] As a preferred embodiment of the drying and crystallization system described in this utility model, the steam circulation unit further includes a live steam generator for conveying live steam to the jacket and for preheating the liquid to be treated, and the live steam generator is connected to the jacket via a pipeline.

[0013] As a preferred embodiment of the drying and crystallization system described in this utility model, the steam circulation unit further includes a buffer separator for separating steam and foam, the buffer separator being located between the evaporation chamber and the steam outlet channel.

[0014] As a preferred embodiment of the drying and crystallization system described in this utility model, it further includes a liquid conveying unit, which includes a preheater for preheating the liquid to be processed and a condensate tank for collecting condensate in the evaporation chamber.

[0015] The preheated liquid to be treated is connected to the liquid inlet of the evaporation chamber via a pipeline.

[0016] The condensate tank is connected to the evaporation chamber via a pipe.

[0017] As a preferred embodiment of the drying and crystallization system described in this utility model, the liquid delivery unit further includes a liquid spraying pump connected between the condensate tank and the compressor via a pipeline, wherein the liquid spraying pump delivers condensate to the compressor for cooling.

[0018] In a preferred embodiment of the drying and crystallization system described in this utility model, the liquid delivery unit further includes an oil-cooled pump connected to the compressor via a pipeline for cooling the compressor's lubricating oil.

[0019] As a preferred embodiment of the drying and crystallization system described in this utility model, the evaporation unit further includes a stirring module for agitating the liquid to be treated in the evaporation chamber, which is used to prevent the crystals from adhering to the inner wall of the evaporation chamber during the evaporation process.

[0020] As a preferred embodiment of the MVR drying and crystallization system of this utility model, the stirring module includes a stirring shaft disposed in the evaporation chamber and a plurality of scrapers connected to the stirring shaft.

[0021] The scraper is attached to the inner wall of the evaporation chamber, and a drive mechanism for driving the stirring shaft to rotate is provided on one side of the evaporation chamber.

[0022] As a preferred embodiment of the MVR drying and crystallization system of this utility model, the stirring module further includes a pusher plate disposed on one side of the stirring shaft, and the movement trajectory of the pusher plate passes through the waste discharge port.

[0023] The beneficial effects of this MVR drying and crystallization system are as follows: This system uses multiple evaporation chambers connected in parallel to discharge crystals at staggered times, avoiding insufficient steam supply from the compressor inlet. This solves the problem of high energy consumption in traditional steam crystallization equipment that uses live steam as an energy source. It also solves the problem of MVR compressors in drying and crystallization equipment requiring live steam as an auxiliary and frequent start-stop operations. This system achieves low energy consumption, continuous operation, and the purpose of material crystallization and drying without frequent compressor shutdowns. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a three-dimensional structural diagram of the MVR-type drying and crystallization system of this utility model.

[0026] Figure 2 This is a three-dimensional structural diagram of the MVR-type drying and crystallization system of this utility model from another perspective.

[0027] Figure 3 This is a three-dimensional structural diagram of the evaporation unit of the MVR-type drying and crystallization system of this utility model.

[0028] Figure 4 This is a three-dimensional structural diagram of the evaporation chamber of the MVR-type drying and crystallization system of this utility model.

[0029] Figure 5 This is a side view cross-sectional diagram of the evaporation chamber of the MVR-type drying and crystallization system of this utility model.

[0030] Figure 6 This is a schematic diagram of the composition and structure of the MVR-type drying and crystallization system of this utility model.

[0031] Figure 7 This is a top view of the internal structure of the evaporation chamber of the MVR-type drying and crystallization system of this utility model.

[0032] Figure 8 This is a three-dimensional structural diagram of the stirring module of the MVR-type drying and crystallization system of this utility model.

[0033] Figure 9 This is a top view of the stirring module of the MVR-type drying and crystallization system of this utility model. Detailed Implementation

[0034] To make the objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.

[0035] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0036] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments. Example

[0037] Reference Figures 1-5 This is the first embodiment of the present invention, which provides an MVR-type drying and crystallization system that can achieve staggered discharge of crystals and maintain the effect of compressor inlet steam supply. It includes an evaporation unit 100 and a steam circulation unit 200. The evaporation unit 100 is used to boil and evaporate the liquid to be treated. The steam circulation unit 200 introduces live steam into the evaporation unit 100 to preheat the liquid being evaporated. The generated secondary steam is then compressed by the compressor to increase its temperature and pressure, and then returned to the evaporation unit 100 as heating steam, thus achieving steam recycling.

[0038] Specifically, the evaporation unit 100 includes at least two sets of evaporation chambers 101 arranged in parallel. Each set of evaporation chambers 101 is provided with an inlet for the liquid to be treated, a waste outlet, and a heating module 102 for heating the liquid to be treated to boiling evaporation. The liquid to be treated is introduced into the evaporation chamber 101 through the liquid to be treated inlet. At least two sets of evaporation chambers 101 are provided. In this embodiment, the heating module 102 adopts a heat exchange method, which raises the temperature by exchanging heat between the liquid to be treated and compressed steam. After the liquid to be treated boils and evaporates, the remaining solid crystals are discharged through the waste outlet. The condensate generated after the liquid to be treated boils and evaporates is collected at the bottom of the evaporation chamber 101 and led out through a pipe.

[0039] Furthermore, the steam circulation unit 200 includes a compressor 201 for compressing steam. Each evaporation chamber 101 is connected to the compressor 201 via a steam outlet channel 202 and a steam inlet channel 203 in the direction of steam flow. The secondary steam generated by the boiling of the liquid to be treated in the evaporation chamber 101 flows into the inlet of the compressor 201 through the steam outlet channel 202. After being compressed by the compressor 201 to increase its temperature and pressure, it is sent back to the evaporation chamber 101 as heating steam through the steam inlet channel 203, thereby realizing the recycling of steam and reducing energy consumption. In this way, the steam outlet channel 202 and the steam inlet channel 203 of each evaporation chamber 101 are connected to the inlet and outlet of the same compressor 201, respectively, thus forming a parallel structure.

[0040] In this system, at least two sets of evaporation chambers 101 have their waste discharge outlets not open simultaneously. The waste discharge outlets can be controlled to close via control valves. By connecting two or more sets of evaporation chambers 101 in parallel to the same compressor 201 in the MVR system, the discharge times are staggered, ensuring the steam supply to the air inlet of the compressor 201 in the MVR system, thereby achieving stable and continuous operation of the equipment.

[0041] Furthermore, the heating module 102 includes a jacket disposed on the outer wall of each evaporation chamber 101, allowing a heat transfer medium to pass through. The liquid to be treated is located inside the evaporation chamber 101. The heat transfer medium flows through the jacket on the outer wall, and the liquid to be treated inside the evaporation chamber 101 absorbs heat through contact with the jacket wall, thereby raising the temperature until the liquid to be treated boils and evaporates. In this embodiment, the heat transfer medium is steam, including live steam supplied by the live steam generator 204 and high-temperature steam compressed by the compressor 201. In this embodiment, the jacket is directly connected to the outlet of the compressor 201 through the steam inflow channel 203, thereby raising the temperature inside the evaporation chamber 101 until the liquid to be treated boils and evaporates.

[0042] Preferably, the steam circulation unit 200 also includes a live steam generator 204 connected to the pipes of the evaporation chamber 101, used to deliver live steam to each group of evaporation chambers 101 to preheat the liquid to be treated. The live steam generator 204 is used to directly generate or provide initial live steam, which is introduced into the jacket to preheat the initial liquid to be treated in the evaporation chamber 101. After secondary steam is generated, it is replaced by heated and pressurized steam introduced into the evaporation chamber 101 through the compressor 201, thereby saving the amount of live steam involved and saving energy.

[0043] In an optional embodiment, the steam circulation unit 200 further includes a buffer separator 205 disposed between the evaporation chamber 101 and the steam outlet channel 202 for separating steam and foam. The buffer separator 205 is disposed above each evaporation chamber 101 and is generally filled with Pall rings or demister screens to filter and separate impurities such as foam contained in the steam.

[0044] Example 2

[0045] Reference Figures 1-9 This is the second embodiment of the present invention. Unlike the previous embodiment, this embodiment provides a liquid delivery unit 300 and a stirring module 103 to optimize the operation of the system equipment.

[0046] Specifically, the liquid delivery unit 300 includes a preheater 301 for preheating the liquid to be treated, and a condensate tank 302 for collecting condensate in the evaporation chamber 101. The liquid to be treated, preheated by the preheater 301, is connected to the liquid inlet of the evaporation chamber 101 via a pipe. The preheater 301 can use conventional electric heating to heat the liquid to be treated flowing through the pipe to a suitable temperature before it is introduced into the evaporation chamber 101. A drain outlet is provided near the lower part of the evaporation chamber 101, and the condensate tank 302 is connected to the drain outlet via a pipe to collect the condensate generated in the evaporation chamber 101 and store it in the condensate tank 302.

[0047] Furthermore, the liquid delivery unit 300 also includes a liquid injection pump 303 connected via a pipeline between the condensate tank 302 and the compressor 201. The liquid injection pump 303 delivers condensate to the compressor 201 to cool the screw of the compressor 201. In addition, an oil cooling pump 304 connected via a pipeline to the compressor 201 can cool the bearing lubricating oil of the compressor 201, thereby maintaining the stable operation of the compressor 201. Preferably, the condensate tank 302 is also connected via a pipeline to an internal circulation and non-condensable gas discharge system to discharge non-condensable gases from the system and maintain the normal operation of the system.

[0048] The evaporation unit 100 also includes a stirring module 103 disposed in the evaporation chamber 101, which is used to maintain the flow state of the liquid to be treated in the evaporation chamber 101 and to prevent the crystals from adhering to the wall during the evaporation process by stirring the liquid to be treated in the evaporation chamber 101.

[0049] Preferably, the stirring module 103 includes a stirring shaft 103a disposed within the evaporation chamber 101, and several sets of scrapers 103b connected to the stirring shaft 103a. These scrapers 103b can be evenly distributed along the axial direction of the stirring shaft 103a. A drive mechanism for rotating the stirring shaft 103a is provided on one side of the evaporation chamber 101. In this embodiment, the evaporation chamber 101 is configured as a horizontal cylindrical shape. The drive mechanism is driven by a motor, and the output end of the motor drives the stirring shaft 103a to rotate. The scrapers 103b connected to the stirring shaft 103a rotate along with the stirring shaft 103a, causing the liquid to be processed to flow. The scrapers 103b are preferably positioned close to the inner wall of the evaporation chamber 101, allowing them to scrape off solid crystals adhering to the inner wall of the evaporation chamber 101 during rotation.

[0050] Furthermore, the stirring module 103 also includes a pusher plate 103c located on one side of the stirring shaft 103a. The movement trajectory of the pusher plate 103c passes through the waste discharge port. When discharge is required, the waste discharge port is opened, and the pusher plate 103c pushes the collected solid crystals to the waste discharge port for discharge during rotation. The pusher plate 103c and the scraper 103b can be integrated. The scraper 103b used for stirring and scraping can be designed to have a smaller projected area on the tangential direction of the stirring shaft 103a than the pusher plate 103c used for pushing solid waste. Since the scraper 103b contacts and scrapes the inner wall of the evaporation chamber 101, it can generally be designed to be softly connected to the stirring shaft 103a via a spring to reduce wear; while the pusher plate 103c needs to be rigidly connected to the stirring shaft 103a to ensure the effectiveness of pushing solid waste.

[0051] In one alternative embodiment, either the scraper 103b or the pusher plate 103c can be spiral-shaped. The spiral structure not only agitates the liquid to be treated and scrapes off the solid crystals on the inner wall of the evaporation chamber 101, but also pushes the scraped solid crystals axially, which facilitates centralized discharge.

[0052] The rest of the structure is the same as in Example 1.

[0053] Working principle: The liquid to be treated is preheated by the preheater 301 and then introduced into the evaporation chamber 101 through the liquid to be treated inlet. Then, the live steam generated by the live steam generator 204 is introduced into the jacket of the outer wall of the evaporation chamber 101 to heat the liquid to be treated in the evaporation chamber 101, thereby raising the temperature in the evaporation chamber 101 until the liquid to be treated boils and evaporates. At the same time, the drive mechanism is turned on to drive the stirring shaft 103a to rotate. The scraper 103b connected to the stirring shaft 103a drives the liquid to be treated to flow as it rotates in the forward, reverse and intermittent directions with the stirring shaft 103a. During the rotation, the scraper 103b scrapes off the solid crystals adhering to the inner wall of the evaporation chamber 101.

[0054] The secondary steam generated by the boiling of the liquid to be treated in the evaporation chamber 101 is separated from the foam by the buffer separator 205. The steam after removing the foam flows into the air inlet of the compressor 201 through the steam outlet channel 202. After being compressed by the compressor 201 to increase the temperature and pressure, it is sent back to the jacket of the outer wall of the evaporation chamber 101 as heating steam through the steam inlet channel 203 to realize the recycling of steam.

[0055] The condensate produced after the liquid to be treated boils and evaporates is collected at the bottom of the evaporation chamber 101 and led out to the condensate tank 302 through a pipe. The liquid injection pump 303 is turned on to deliver the condensate to the compressor 201 to cool the screw of the compressor 201. After the compressor 201 has been running for a period of time, the oil cooling pump 304 is turned on to cool the bearing lubricating oil of the compressor 201, thereby maintaining the stable operation of the compressor 201. The internal circulation and non-condensable gas discharge system is turned on to discharge the non-condensable gas in the system and maintain the normal operation of the system.

[0056] The waste discharge ports of each group of evaporation chambers 101 are opened in staggered time to discharge the material. That is, when the waste discharge port of any group of evaporation chambers 101 is opened, at least one group of evaporation chambers 101 is kept in a closed state. During the rotation of the push plate 103c, the collected solid crystals are pushed to the opened waste discharge port for discharge.

[0057] It is important to note that the constructions and arrangements of this application shown in several different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, those who consult this disclosure will readily understand that many modifications are possible (e.g., changes in the size, dimensions, structure, shape and proportion of various elements, as well as parameter values ​​(e.g., temperature, pressure, etc.), mounting arrangements, use of materials, color, orientation, etc.) without substantially departing from the novel teachings and advantages of the subject matter described in this application). For example, an element shown as integrally formed may be composed of multiple parts or elements, the position of elements may be inverted or otherwise altered, and the nature or number or position of discrete elements may be changed or altered. Therefore, all such modifications are intended to be included within the scope of this utility model. The order or sequence of any process or method steps may be changed or reordered according to alternative embodiments. In the claims, any "device plus function" clause is intended to cover the structure described herein that performs the function, and not only structural equivalents but also equivalent structures. Without departing from the scope of this invention, other substitutions, modifications, alterations, and omissions may be made in the design, operation, and arrangement of the exemplary embodiments. Therefore, this invention is not limited to the specific embodiments, but extends to various modifications that still fall within the scope of the appended claims.

[0058] Furthermore, in order to provide a concise description of exemplary embodiments, not all features of actual embodiments (i.e., those features that are not relevant to the best mode of carrying out the present invention as currently considered, or those features that are not relevant to implementing the present invention) may be omitted.

[0059] It should be understood that numerous specific implementation decisions can be made during the development of any practical implementation, such as in any engineering or design project. Such development efforts may be complex and time-consuming, but for those skilled in the art who benefit from this disclosure, the development effort will be a routine work of design, manufacturing, and production without requiring much experimentation.

[0060] It should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. An MVR drying crystallization system, characterized by: The utility model relates to a waste liquid evaporating device, comprising, an evaporation unit (100) comprising at least two groups of evaporation chambers (101) arranged in parallel, each group of evaporation chambers (101) is provided with a liquid inlet and a heating module (102) for heating the liquid to be treated to boiling evaporation; and a steam circulation unit (200) comprising a compressor (201) for compressing steam, the compressor (201) and each group of evaporation chambers (101) are connected by a steam outlet channel (202) and a steam inlet channel (203) in the direction of steam flow; wherein, at least two groups of evaporation chambers (101) have different waste discharge openings.

2. The MVR drying crystallization system of claim 1, wherein: The heating module (102) comprises a sandwich layer allowing the passage of a heat medium, which is arranged on the outer wall of the evaporation chamber (101); the sandwich layer is connected to the gas outlet of the compressor (201) through the steam inlet channel (203).

3. The MVR drying crystallization system of claim 2, wherein: The steam circulation unit (200) further comprises a live steam generator (204) for delivering live steam into the sandwich layer and preheating the liquid to be treated, which is connected to the sandwich layer through a pipeline.

4. The MVR drying crystallization system of any one of claims 1-3, wherein: The steam circulation unit (200) further comprises a buffer separator (205) for separating steam and foam, which is arranged between the evaporation chamber (101) and the steam outlet channel (202).

5. The MVR drying crystallization system of any one of claims 1-3, wherein: The utility model further comprises a liquid delivery unit (300), which comprises a preheater (301) for preheating the liquid to be treated, and a condensate tank (302) for collecting condensed water in the evaporation chamber (101); the liquid to be treated preheated by the preheater (301) is connected to the liquid inlet of the evaporation chamber (101) through a pipeline, the condensate tank (302) is connected to the evaporation chamber (101) through a pipeline.

6. The MVR drying crystallization system of claim 5, wherein: The liquid delivery unit (300) further comprises a liquid injection pump (303) connected between the condensate tank (302) and the compressor (201) through a pipeline, which delivers the condensed water to the compressor (201) for cooling.

7. The MVR drying crystallization system of claim 5, wherein: The liquid delivery unit (300) further comprises an oil cooling pump (304) connected to the compressor (201) through a pipeline, which is used to cool the lubricating oil of the compressor (201).

8. The MVR drying crystallization system of any one of claims 1-3 or 6-7, wherein: The evaporation unit (100) further comprises a stirring module (103) for agitating the liquid to be treated in the evaporation chamber (101), which is used to prevent crystalline substances from adhering to the inner wall of the evaporation chamber (101) during evaporation.

9. The MVR drying crystallization system of claim 8, wherein: The stirring module (103) comprises a stirring shaft (103a) arranged in the evaporation chamber (101), and a plurality of groups of scrapers (103b) connected to the stirring shaft (103a); the scrapers (103b) are attached to the inner wall of the evaporation chamber (101), and one side of the evaporation chamber (101) is provided with a driving mechanism for driving the stirring shaft (103a) to rotate.

10. The MVR drying crystallization system of claim 9, wherein: The stirring module (103) further comprises a push plate (103c) arranged on one side of the stirring shaft (103a), and the movement trajectory of the push plate (103c) passes through the waste discharge opening.

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