阅读说明：本技术 机械蒸汽再压缩mvr热泵干燥系统 (Mechanical vapor recompression MVR heat pump drying system ) 是由 侯超 蔺雪军 杨鲁伟 魏娟 陶磊 于 2020-06-23 设计创作，主要内容包括：本发明实施例涉及物料干燥技术领域,提供了一种机械蒸汽再压缩MVR热泵干燥系统。本发明实施例提供的机械蒸汽再压缩MVR热泵干燥系统包括：干燥器、蒸汽压缩机和喷射泵,干燥器的第一出口与蒸汽压缩机的入口连接,蒸汽压缩机的出口与喷射泵的第一入口连接,喷射泵的出口与干燥器的第一入口连接,以使干燥器、蒸汽压缩机和喷射泵之间形成二次蒸汽热交换循环回路。本发明实施例提供的机械蒸汽再压缩MVR热泵干燥系统,通过设置循环回路,利用通过蒸汽压缩机将干燥器干燥过程中产生的二次蒸汽压缩成高温高压的蒸汽,然后作为热源进入干燥器对物料进行干燥,使得二次蒸汽循环利用,提高了干燥系统的能源利用率。(The embodiment of the invention relates to the technical field of material drying, and provides a mechanical vapor recompression MVR heat pump drying system. The mechanical vapor recompression MVR heat pump drying system provided by the embodiment of the invention comprises: the dryer comprises a dryer, a steam compressor and an injection pump, wherein a first outlet of the dryer is connected with an inlet of the steam compressor, an outlet of the steam compressor is connected with a first inlet of the injection pump, and an outlet of the injection pump is connected with the first inlet of the dryer, so that a secondary steam heat exchange circulation loop is formed among the dryer, the steam compressor and the injection pump. According to the mechanical vapor recompression MVR heat pump drying system provided by the embodiment of the invention, by arranging the circulation loop, secondary vapor generated in the drying process of the dryer is compressed into high-temperature and high-pressure vapor through the vapor compressor, and then the high-temperature and high-pressure vapor is used as a heat source to enter the dryer to dry materials, so that the secondary vapor is recycled, and the energy utilization rate of the drying system is improved.)

1. The utility model provides a mechanical vapor recompression MVR heat pump drying system which characterized in that includes: the dryer comprises a dryer, a steam compressor and an injection pump, wherein a first outlet of the dryer is connected with an inlet of the steam compressor, an outlet of the steam compressor is connected with a first inlet of the injection pump, and an outlet of the injection pump is connected with a first inlet of the dryer, so that a secondary steam heat exchange circulation loop is formed among the dryer, the steam compressor and the injection pump.

2. The Mechanical Vapor Recompression (MVR) heat pump drying system of claim 1, wherein the secondary vapor heat exchange cycle further comprises: and the inlet of the secondary steam purification device is connected with the first outlet of the dryer, and the outlet of the secondary steam purification device is connected with the inlet of the steam compressor through a first pipeline.

3. The Mechanical Vapor Recompression (MVR) heat pump drying system of claim 2, further comprising an exhaust fan, wherein an inlet of the exhaust fan is connected to the first pipeline through a second pipeline, and an outlet of the exhaust fan is used for exhausting non-condensable gas.

4. The mechanical vapor recompression MVR heat pump drying system of claim 3, further comprising a first regulating valve disposed on the second pipeline.

5. The mechanical vapor recompression MVR heat pump drying system of any one of claims 1 to 4, further comprising: and an inlet of the condensed liquid tank is connected with a second outlet of the dryer, and a first outlet of the condensed liquid tank is connected with a second inlet of the jet pump through a third pipeline.

6. The mechanical vapor recompression MVR heat pump drying system of claim 5, wherein a second regulating valve is disposed on the third pipeline.

7. The mechanical vapor recompression MVR heat pump drying system of claim 5, further comprising: a feed conveyor having a first inlet for receiving wet material and a second inlet connected to a second outlet of the condensate tank; the first outlet of the feed conveyor is connected to the second inlet of the dryer and the second outlet of the feed conveyor is used for draining condensate.

8. The mechanical vapor recompression MVR heat pump drying system of claim 1, further comprising: and an inlet of the discharging conveyor is connected with a third outlet of the dryer, and an outlet of the discharging conveyor is used for discharging dry materials.

9. The mechanical vapor recompression MVR heat pump drying system of claim 1, wherein the dryer is any one of a hollow blade dryer, a tray dryer, a tube bundle dryer or a scraper dryer.

10. The mechanical vapor recompression MVR heat pump drying system of claim 1, wherein the vapor compressor is any one of a screw type vapor compressor, a Roots type vapor compressor or a centrifugal type vapor compressor.

Technical Field

The invention relates to the technical field of material drying, in particular to a mechanical vapor recompression MVR heat pump drying system.

Background

The material drying relates to a plurality of fields such as chemical industry, pharmacy, mining, food, environmental protection, and the like, and is not only an indispensable basic link in industrial and agricultural production, but also a main energy consumption link. Drying is used as a process of net expenditure of energy, generally, air is used as a medium, primary energy, electric heating and the like are used as heat sources, and low-humidity hot air and wet materials are used for heat and moisture exchange to take away moisture in the materials. The energy consumption of the whole drying process is high, the energy consumption reaches 3200-.

According to statistics, the energy utilization rate of drying equipment commonly used in China is only 40% -50%, while the energy utilization rate of foreign drying equipment is more than 70%, and the potential of energy conservation is huge.

MVR is the abbreviation of mechanical vapor recompression (mechanical vapor recompression) technology. The mechanical vapor recompression MVR heat pump technology is an efficient and environment-friendly energy-saving technology, is widely applied to the industries of evaporative crystallization, environmental protection and the like at present, and is rarely applied to the field of material drying. Therefore, under the great trend of energy conservation and emission reduction, the mechanical vapor recompression MVR heat pump technology is applied to the drying process so as to reduce the energy consumption of the drying system and improve the energy utilization rate.

Disclosure of Invention

In order to solve the problems of high energy consumption and low energy utilization rate of a drying system in the prior art, the embodiment of the invention provides a mechanical vapor recompression MVR heat pump drying system.

According to one embodiment of the invention, the mechanical vapor recompression MVR heat pump drying system comprises: the dryer comprises a dryer, a steam compressor and an injection pump, wherein a first outlet of the dryer is connected with an inlet of the steam compressor, an outlet of the steam compressor is connected with a first inlet of the injection pump, and an outlet of the injection pump is connected with a first inlet of the dryer, so that a secondary steam heat exchange circulation loop is formed among the dryer, the steam compressor and the injection pump.

According to one embodiment of the invention, the secondary steam heat exchange cycle further comprises: and the inlet of the secondary steam purification device is connected with the first outlet of the dryer, and the outlet of the secondary steam purification device is connected with the inlet of the steam compressor through a first pipeline.

According to one embodiment of the invention, the mechanical vapor recompression MVR heat pump drying system further comprises an exhaust fan, wherein an inlet of the exhaust fan is connected to the first pipeline through a second pipeline, and an outlet of the exhaust fan is used for discharging non-condensable gas.

According to an embodiment of the invention, a first regulating valve is further arranged on the second pipeline.

According to one embodiment of the invention, the mechanical vapor recompression MVR heat pump drying system further comprises: and an inlet of the condensed liquid tank is connected with a second outlet of the dryer, and a first outlet of the condensed liquid tank is connected with a second inlet of the jet pump through a third pipeline.

According to one embodiment of the invention, a second regulating valve is arranged on the third pipeline.

According to one embodiment of the invention, the mechanical vapor recompression MVR heat pump drying system further comprises: a feed conveyor having a first inlet for receiving wet material and a second inlet connected to a second outlet of the condensate tank; the first outlet of the feed conveyor is connected to the second inlet of the dryer and the second outlet of the feed conveyor is used for draining condensate.

According to one embodiment of the invention, the mechanical vapor recompression MVR heat pump drying system further comprises: and an inlet of the discharging conveyor is connected with a third outlet of the dryer, and an outlet of the discharging conveyor is used for discharging dry materials.

According to an embodiment of the invention, the dryer is any one of a hollow blade dryer, a tray dryer, a tube bundle dryer or a scraper dryer.

According to an embodiment of the invention, the steam compressor is any one of a screw-type steam compressor, a roots-type steam compressor or a centrifugal-type steam compressor.

According to the mechanical vapor recompression MVR heat pump drying system provided by the embodiment of the invention, the dryer, the vapor compressor and the jet pump are arranged into the circulation loop, secondary vapor generated in the drying process of the dryer is compressed into high-temperature and high-pressure vapor through the vapor compressor, and the high-temperature and high-pressure vapor is driven by the jet pump to be injected into the dryer to be used as a heat source to dry materials, SO that the secondary vapor is recycled, an external heat source and circulating cooling water are not needed in the whole drying process, the energy utilization rate of the drying system is improved, and SO is reduced₂、CO₂And dust and dry tail gas are discharged, and the environmental benefit is considerable.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a mechanical vapor recompression MVR heat pump drying system according to an embodiment of the present invention.

Description of reference numerals:

1-a dryer; 2-secondary steam purification device; 3-a vapor compressor; 4-a jet pump; 5-an exhaust fan; 6-a condensate tank; 7-a discharge conveyor; 8-a feed conveyor; 11-a first conduit; 12-a second conduit; 13-a third line; 21-a first regulating valve; 22-second regulating valve.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In addition, in the description of the present invention, unless otherwise specified, "plurality", "plural groups" means two or more, and "several", "several groups" means one or more.

Referring now to fig. 1, an embodiment of the present invention will be described. It should be understood that the following description is only exemplary embodiments of the present invention and does not constitute any particular limitation of the present invention.

As shown in fig. 1, in one embodiment of the present invention, a mechanical vapor recompression MVR heat pump drying system comprises: the dryer comprises a dryer 1, a vapor compressor 3 and an injection pump 4, wherein a first outlet of the dryer 1 is connected with an inlet of the vapor compressor 3, an outlet of the vapor compressor 3 is connected with a first inlet of the injection pump 4, and an outlet of the injection pump 4 is connected with the first inlet of the dryer 1, so that a secondary vapor heat exchange circulation loop is formed among the dryer 1, the vapor compressor 3 and the injection pump 4.

Specifically, the wet material is heated in the drying cavity of the dryer 1, the moisture is heated and evaporated, the generated secondary steam is discharged from the first outlet of the dryer 1 and enters the steam compressor 3, the steam compressor 3 compresses the steam into high-temperature and high-pressure steam, and then the steam is discharged from the outlet of the steam compressor 3 and enters the suction chamber of the injection pump 4 through the first inlet of the injection pump 4. In the jet pump 4, the compressed steam is used for ejecting and mixing the non-condensable gas in the condensed liquid tank 6, and then the non-condensable gas enters the condensation side of the dryer 1 to be used as a heat source to heat the material. The secondary steam that produces among the material heating process gets into vapor compressor 3 again and compresses into the high-temperature high-pressure steam as the heat source of desicator 1 heating material, so recycles repeatedly, makes and forms secondary steam heat exchange circulation circuit between desicator 1, vapor compressor 3 and the jet pump 4, carries out make full use of to the secondary steam latent heat that produces among the material drying process, and whole drying process does not need external heat source, has greatly improved heat pump drying system's energy utilization.

Further, the high-temperature and high-pressure steam entering the condensation side of the dryer 1 exchanges heat with the wet material to form condensate, and the condensate is discharged into the condensate tank 6 through a second outlet of the dryer 1. And the dry materials reaching the water content requirement are discharged to a discharging conveyor 7 from a third outlet of the dryer 1 and then discharged out of the heat pump drying system.

Further, in the embodiment of the present invention, the dryer 1 is optionally a tray dryer, a tube bundle dryer, a blade dryer or a hollow blade dryer. In one embodiment of the invention, the dryer 1 is a hollow blade dryer.

In one embodiment of the invention, the vapor compressor 3 is optionally a screw-type vapor compressor, a roots-type vapor compressor, or a centrifugal vapor compressor, or the like.

It will of course be appreciated that the form of the dryer 1 and the steam compressor 3 is merely illustrative and that alternative types of dryers and steam compressors may be used in the present invention. This may be done according to the particular use case and the invention is not limited thereto.

The mechanical vapor recompression MVR heat pump drying system provided by the embodiment of the invention can be widely applied to the drying process of materials such as sludge, dregs of a decoction, coal slime, salts and the like. According to the mechanical vapor recompression MVR heat pump drying system provided by the embodiment of the invention, the dryer, the vapor compressor and the jet pump are arranged into the circulation loop, secondary vapor generated in the drying process of the dryer is compressed into high-temperature and high-pressure vapor through the vapor compressor, the high-temperature and high-pressure vapor is driven by the jet pump to be injected into the dryer to be used as a heat source to dry materials, so that the secondary vapor is recycled, an external heat source and circulating cooling water are not needed in the whole drying process, and meanwhile, the jet pump can drive gas in the heat pump drying system to circulate, so that the heat exchange efficiency of the dryer is improved, and the energy utilization rate of the heat pump drying circulation system provided by the embodiment of the invention is further improved.

As shown in fig. 1, in one embodiment of the present invention, the mechanical vapor recompression MVR heat pump drying system further comprises: and the inlet of the condensed liquid tank 6 is connected with the second outlet of the dryer 1, and the first outlet of the condensed liquid tank 6 is connected with the second inlet of the jet pump 4 through a third pipeline 13.

Specifically, the secondary steam generated by drying the wet material in the dryer 1 is compressed into high-temperature and high-pressure steam by the steam compressor 3, and then discharged into the suction chamber of the ejector pump 4 through the outlet of the steam compressor 3. Meanwhile, high-temperature condensate generated after heat exchange in the dryer 1 and non-condensable gas formed in the drying process enter the condensate tank 6 through a second outlet of the dryer 1, and the high-temperature condensate in the condensate tank 6 is discharged into the feeding conveyor 8 through the second outlet to serve as a heat source for preheating wet materials. The non-condensable gas in the condensate tank 6 enters the suction chamber of the injection pump 4 through a third pipeline 13, and enters the condensation side of the dryer 1 after being mixed with the high-temperature and high-pressure steam compressed by the steam compressor 3.

Further, a second regulating valve 22 is provided on the third line 13. With the increasing of the content of the non-condensable gas in the heat pump drying system of the embodiment of the invention, the content of the non-condensable gas entering the dryer 1 can be adjusted by adjusting the second adjusting valve 22.

As shown in fig. 1, in one embodiment of the invention, the secondary steam heat exchange cycle further comprises: the secondary steam purification device 2, the entry of secondary steam purification device 2 and the first exit linkage of desicator 1, the export of secondary steam purification device 2 is through the entry linkage of first pipeline 11 with vapor compressor 3.

In one embodiment of the present invention, the mechanical vapor recompression MVR heat pump drying system further comprises: and an inlet of the exhaust fan 5 is connected to the first pipeline 11 through a second pipeline 12, and an outlet of the exhaust fan 5 is used for discharging non-condensable gas.

Specifically, the secondary steam generated by drying the wet material in the dryer 1 firstly enters the secondary steam purification device 2 for purification, and the secondary steam enters the steam compressor 3 through the first pipeline 11 after impurities such as dust and the like carried in the secondary steam purification device 2 are removed, and is compressed into high-temperature and high-pressure steam. Further, second pipeline 12 is connected on first pipeline 11, and the produced noncondensable gas of material drying process passes through secondary steam purifier 2 in desicator 1 after, discharges to exhaust fan 5 through second pipeline 12, and exhaust fan 5 is with partly noncondensable gas discharge. The discharged non-condensable gas can be further treated or recycled, and the pollution of the waste gas to the environment is reduced.

Further, a first regulating valve 21 is disposed on the second pipeline 12. With the continuously increased content of the non-condensable gas in the mechanical vapor recompression MVR heat pump drying system, the first adjusting valve 21 is adjusted, and a small amount of non-condensable gas can be periodically discharged through the exhaust fan 5 connected to the second pipeline 12, so that the dynamic balance in the heat pump drying system is achieved.

As shown in fig. 1, in one embodiment of the present invention, the mechanical vapor recompression MVR heat pump drying system further comprises: a feeding conveyor 8, a first inlet of the feeding conveyor 8 is used for receiving wet materials, and a second inlet of the feeding conveyor 8 is connected with a second outlet of the condensed liquid tank 6; a first outlet of the feed conveyor 8 is connected to a second inlet of the dryer 1 and a second outlet of the feed conveyor 8 is used for draining off condensate.

Specifically, wet materials enter the feeding conveyor 8 through a first inlet of the feeding conveyor 8, evaporation condensate and the wet materials are subjected to heat exchange in the feeding conveyor 8, the wet materials are preheated, and the preheated materials enter the dryer 1 through a first outlet of the feeding conveyor 8 to be dried. High-temperature condensate in the condensate tank 6 enters the feeding conveyor 8 through a second outlet of the condensate tank 6 to preheat wet materials, and meanwhile, waste heat recovery of the high-temperature condensate is achieved. The condensate after heat exchange with the wet material is discharged out of the heat pump drying system through a second outlet of the feeding conveyor 8 and is directly recycled or further processed.

Further, the second outlet of the feeding conveyor 8 is a hot fluid outlet. In one embodiment of the invention, the feed conveyor 8 is optionally a heat exchange screw conveyor. It will of course be appreciated that the form of the infeed conveyor 8 is merely illustrative and that alternative types of conveyors may be used in the present invention. This may be done according to the particular use case and the invention is not limited thereto.

As shown in fig. 1, in one embodiment of the present invention, the mechanical vapor recompression MVR heat pump drying system further comprises: and an outlet conveyor 7, wherein an inlet of the outlet conveyor 7 is connected with a third outlet of the dryer 1, and an outlet of the outlet conveyor 7 is used for discharging dry materials.

Specifically, after the material is dried in the dryer 1, the dry material meeting the moisture content requirement is discharged to the discharging conveyor 7 through the third outlet of the dryer 1, and then is discharged out of the heat pump drying system through the outlet of the discharging conveyor 7. Further, in one embodiment of the invention, the outfeed conveyor 7 is optionally a screw conveyor. It will of course be appreciated that the form of the outfeed conveyor 7 is merely illustrative and that alternative types of conveyors may be used in the present invention. This may be done according to the particular use case and the invention is not limited thereto.

The mechanical vapor recompression MVR heat pump drying system provided by the embodiment of the invention has the advantages of reasonable design and simple structure, and can realize full-process automatic control. Because the heat pump drying system directly recovers the latent heat of the secondary steam generated in the material drying process, the energy consumption in the drying process is effectively reduced, and the SO is reduced₂、CO₂The emission of dust and dry tail gas provides technical support for the development and popularization of the mechanical vapor recompression MVR heat pump drying technology, and has very high economic benefit and social benefit.

The working principle of the mechanical vapor recompression MVR heat pump drying system provided by the embodiment of the invention is specifically illustrated and described as follows:

the wet material enters the feed conveyor 8 to exchange heat with the evaporative condensate to preheat the wet material. The wet material after preheating gets into and heats the drying in the desicator 1, and the secondary steam that produces among the drying process and a small amount of noncondensable gas get into in the secondary steam purifier 2 through the first export of desicator 1 and carry out purification treatment to impurity such as dust smugglied secretly, and the secondary steam after the processing gets into vapor compressor 3 through first pipeline 11 and compresses into high-temperature high-pressure steam, and high-temperature high-pressure steam gets into the suction chamber of jet pump 4. The high-temperature high-pressure steam is used for ejecting and mixing part of non-condensable gas in the condensate tank 6 and then used as a heat source to enter a condensation side heating material of the dryer 1, and the high-temperature high-pressure steam completes heat exchange in the dryer 1 to form high-temperature condensate and entrained non-condensable gas and then enters the condensate tank 6 through a second outlet of the dryer 1. The dryer 1, the secondary steam purification device 2, the steam compressor 3 and the injection pump 4 form a secondary steam heat exchange circulation loop, so that the cyclic utilization of the secondary steam is realized, and the energy utilization rate of the heat pump drying system is improved.

When the content of the non-condensable gas in the heat pump drying system is higher, the non-condensable gas can be adjusted through the first adjusting valve 21 arranged on the second pipeline 12, a small amount of non-condensable gas is discharged periodically through the exhaust fan 5, and the discharged non-condensable gas can be further processed to reduce the pollution of the gas to the environment. Meanwhile, the third pipeline 13 is also provided with a second regulating valve 22, and the content of the non-condensable gas entering the dryer 1 can be regulated by regulating the second regulating valve 22.

The material reaching the required moisture content enters the discharging conveyor 7 through the third outlet of the dryer 1, and is discharged through the outlet of the discharging conveyor 7.

High-temperature condensate in the condensate tank 6 enters the feeding conveyor 8 through a second outlet of the condensate tank 6 to preheat wet materials, the condensate after heat exchange is discharged from a second outlet of the feeding conveyor 8, and the discharged condensate can be directly recycled or further processed. The heat pump drying system provided by the embodiment of the invention has the advantages that the non-condensable gas and the condensate which are discharged out of the system are recycled or reprocessed, the pollution to the environment is reduced, and the environmental protection benefit is considerable.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.