Drying system

Abstract

A drying system comprises a drying machine which comprises a furnace body internally provided with a drying cavity and a conveyor penetrating through the drying cavity; the temperature control unit comprises a hot air circulating fan which communicates with the drying cavity and is used for conveying heated air to the drying cavity; the waste discharge fan communicates with the drying cavity and is used for discharging air in the drying cavity out of the furnace body; the control unit is electrically connected with the conveyor, the hot air circulating fan and the waste discharge fan; and the control unit is configured to close the hot air circulating fan and open the waste discharge fan when the conveyor is shut down. When the drying system is used for drying the gypsum board, the gypsum board can be prevented from being overburnt.

Description

Technical Field

[0001] This article relates to gypsum board production technology, especially a drying system. Background Art

[0002] Paper-faced gypsum board is a building board made of building gypsum as the main raw material, mixed with appropriate amounts of fiber reinforcement materials and additives, etc., and poured between the face paper and backing paper of the face paper after mixing with water, and firmly bonded with the face paper. The dryer mainly evaporates the moisture in the wet gypsum board. During the evaporation process, starch is driven to migrate to the joint between the core surface of the gypsum board and the face paper, forming a dry gypsum board with good bonding performance between the gypsum core and the face paper. By adjusting the opening of the fan and steam electric valve in each zone of the dryer, the free water of the gypsum board inside the dryer is fully evaporated, and at the same time, the dihydrate gypsum in the core of the gypsum board is ensured not to be over-dehydrated by high temperature (commonly known as overburning). However, in the actual production process, sometimes there will be equipment failure in the subsequent drying process, resulting in the inability to produce boards and the need to actively stop the dryer for equipment maintenance. When the dryer stops, the circulating hot air blower cannot be turned off in time, and the high temperature inside the dryer will continue for a long time, resulting in the gypsum board in the dryer being prone to overburning. Summary of the invention

[0003] The present application provides a drying system, which includes: The dryer comprises a furnace body with a drying chamber therein and a conveyor passing through the drying chamber; Temperature control unit, including: A hot air circulation fan connected to the drying chamber and used for delivering heated air to the drying chamber; An exhaust fan connected to the drying chamber and used to discharge the air in the drying chamber to outside the furnace; A control unit electrically connected to the conveyor, the hot air circulation fan and the exhaust fan; Wherein, the control unit is configured to turn off the hot air circulation fan and turn on the exhaust fan when the conveyor stops.

[0004] In an illustrative embodiment, the temperature control unit further includes a first heat exchanger; The first heat exchanger includes a first heat exchange channel and a second heat exchange channel; Among them, the first heat exchange flow channel is used for water vapor to pass through, and the two ends of the second heat exchange flow channel are respectively connected to the hot air circulation fan and the drying chamber, so that the hot air circulation fan, the drying chamber and the second heat exchange flow channel form a hot air circulation loop, and the water vapor flowing through the first heat exchange flow channel heats the air flowing through the second heat exchange flow channel.

[0005] In an illustrative embodiment, the temperature control unit further comprises a first electric valve electrically connected to the control unit; The air inlet of the exhaust fan is connected to the hot air circulation loop through the first electric valve; The control unit is configured to open the first electric valve when the conveyor stops.

[0006] In an illustrative embodiment, the temperature control unit further comprises a steam electric regulating valve disposed upstream of the first heat exchange flow channel, the steam electric regulating valve being used to regulate the steam flow input into the first heat exchange flow channel; The steam electric regulating valve is electrically connected to the control unit, and the control unit is further configured to close the steam electric regulating valve when the conveyor stops.

[0007] In an illustrative embodiment, the drying chamber is divided into a plurality of drying zones, and the plurality of drying zones are sequentially arranged along the conveying direction of the conveyor; The temperature control units are provided in plurality, and the hot air circulation fans of the plurality of temperature control units are respectively connected to the plurality of drying areas, and the exhaust fans of the plurality of temperature control units are respectively connected to the plurality of drying areas.

[0008] In an illustrative embodiment, it further comprises a heating coil, wherein the heating coil is disposed in at least a portion of the drying area, and the heating coil is used for heating water to pass through; The drying system also includes a water storage tank for holding replacement water and a water pump communicating between the water storage tank and the heating coil; Among them, the water temperature of the replacement water is lower than the water temperature of the heating water in the heating coil, the water pump is used to pump the replacement water in the water storage tank to the heating coil, the water pump is electrically connected to the control unit, and the control unit is also configured to turn on the water pump when the conveyor stops.

[0009] In an illustrative embodiment, the temperature of the replacement water is 80°C.

[0010] In an illustrative embodiment, it also includes a flash tank and a second electric valve; The flash tank is provided with a mixture inlet, a gas outlet and a liquid outlet. The flash tank is used to perform gas-liquid separation on the gas-water mixture input from the mixture inlet, output the separated water vapor from the gas outlet, and output the separated water from the liquid outlet; The mixture inlet is connected to the outlet end of at least a portion of the first heat exchange flow channel, the liquid outlet is connected to the inlet of the heating coil, and the second electric valve is arranged on the pipeline between the liquid outlet and the heating coil; The second electric valve is electrically connected to the control unit, and the control unit is further configured to close the second electric valve when the conveyor stops.

[0011] In an illustrative embodiment, four drying zones are provided, and the four drying zones are sequentially a first drying zone, a second drying zone, a third drying zone and a fourth drying zone in the conveying direction of the conveyor; The inlet ends of the first heat exchange channels of the first heat exchangers corresponding to the first drying zone, the second drying zone and the third drying zone are externally connected to the water vapor supply pipeline, and the inlet end of the first heat exchange channel of the first heat exchanger corresponding to the fourth drying zone is connected to the gas outlet.

[0012] In an illustrative embodiment, it further includes a second heat exchanger, a condensed water tank, and a preheating fan; The second heat exchanger includes a third heat exchange channel and a fourth heat exchange channel; The inlet end of the third heat exchange channel is connected to the liquid outlet, and the outlet end of the third heat exchange channel is connected to the second electric valve; The inlet end of the fourth heat exchange channel is connected to the air outlet of the preheating fan, and the inlet end of the fourth heat exchange channel is connected to the hot air circulation loops corresponding to the first drying area and the second drying area; The condensed water tank is provided with a first water inlet, a second water inlet, a first water outlet and a second water outlet, the outlet end of the first heat exchange channel of the first heat exchanger corresponding to the fourth drying zone is connected to the first water inlet, and the outlet of the heating coil is also connected to the second water inlet; The water storage tank is provided with a third water inlet connected to the first water outlet and a third water outlet connected to the water inlet of the water pump.

[0013] When the drying system is working normally, the hot air circulation fan is turned on to continuously deliver heated air to the drying chamber of the dryer so that the temperature in the drying chamber is maintained at a high temperature. The conveyor delivers the wet gypsum board to the drying chamber of the dryer. As the gypsum board moves from one end to the other end of the drying chamber driven by the conveyor, the hot air in the drying chamber gradually evaporates the moisture in the wet gypsum board. If the conveyor suddenly stops at this time and the gypsum board remains in the drying chamber, the control unit will immediately turn off the hot air circulation fan so that the hot air circulation fan no longer delivers hot air to the drying chamber. At the same time, the exhaust fan will be immediately turned on to exhaust the hot air in the drying chamber, thereby reducing the temperature in the drying chamber and ensuring that the dihydrate gypsum in the gypsum board core is not excessively dehydrated by the high temperature in the drying chamber.

[0014] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by implementing the present application. Other advantages of the present application can be realized and obtained by the schemes described in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings are used to provide an understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0016] Figure 1 Schematic diagram of a drying system in an embodiment of the present application. DETAILED DESCRIPTION

[0017] The present application describes multiple embodiments, but the description is exemplary rather than restrictive, and it is obvious to those skilled in the art that there may be more embodiments and implementations within the scope of the embodiments described in the present application. Although many possible feature combinations are shown in the drawings and discussed in the specific embodiments, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with any other feature or element in any other embodiment, or may replace any other feature or element in any other embodiment.

[0018] The present application includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The embodiments, features and elements disclosed in the present application may also be combined with any conventional features or elements to form a unique invention scheme. Any features or elements of any embodiment may also be combined with features or elements from other invention schemes to form another unique invention scheme. Therefore, it should be understood that any feature shown and / or discussed in the present application may be implemented individually or in any appropriate combination. Therefore, except for the limitations made according to the attached claims and their equivalents, the embodiments are not subject to other restrictions. In addition, various modifications and changes may be made within the scope of protection of the attached claims.

[0019] In addition, when describing representative embodiments, the specification may have presented the method and / or process as a specific sequence of steps. However, to the extent that the method or process does not rely on the specific order of the steps described herein, the method or process should not be limited to the steps of the specific order described. As will be understood by those of ordinary skill in the art, other sequences of steps are also possible. Therefore, the specific sequence of the steps set forth in the specification should not be interpreted as a limitation to the claims. In addition, the claims for the method and / or process should not be limited to the steps of performing them in the order written, and those skilled in the art can easily understand that these sequences can be changed and still remain within the spirit and scope of the embodiments of the present application.

[0020] like Figure 1 As shown, Figure 1 A drying system 100 in this embodiment is shown. The drying system 100 includes a drying machine 1, a temperature control unit 2 and a control unit. The drying machine 1 is used to dry gypsum boards. The temperature control unit 2 is used to control the temperature in the drying machine 1.

[0021] The drying machine 1 includes a furnace body and a conveyor 12. The furnace body can be constructed as a strip-shaped cavity structure. A drying chamber 11 is arranged in the furnace body. The drying chamber 11 extends from one end of the furnace body to the other end of the furnace body. The conveyor 12 can be a roller conveyor. The conveyor 12 passes through the drying chamber 11. The conveyor 12 can convey the gypsum board from one end of the furnace body to the drying chamber 11, and move along the extension direction of the drying chamber 11 to the other end of the furnace body, and finally output the furnace body from the other end of the furnace body.

[0022] The temperature control unit 2 includes a hot air circulation fan 21 and an exhaust fan 22. The hot air circulation fan 21 and the exhaust fan 22 can both be centrifugal fans, Roots fans or axial flow fans. The hot air circulation fan 21 is connected to the drying chamber 11 of the dryer 1 through a pipeline. The hot air circulation fan 21 is used to transport the heated air to the drying chamber 11 of the dryer 1. The hot air circulation fan 21 transports the heated air to the drying chamber 11, which can increase the temperature in the drying chamber 11 and maintain the high temperature in the drying chamber 11.

[0023] The exhaust fan 22 is connected to the drying chamber 11 of the dryer 1 through a pipeline. The exhaust fan 22 is used to discharge the air in the drying chamber 11 of the dryer 1 to the outside of the oven.

[0024] The control unit is a logic control unit of the drying system 100. The control unit may be a programmable logic controller. The control unit is electrically connected to the conveyor 12, the hot air circulation fan 21 and the exhaust fan 22. The control unit is configured to turn off the hot air circulation fan 21 and turn on the exhaust fan 22 when the conveyor 12 stops.

[0025] When the drying system 100 is working normally, the hot air circulation fan 21 is turned on to continuously convey heated air into the drying chamber 11 of the dryer 1 so that the temperature in the drying chamber 11 is maintained at a high temperature. The conveyor 12 conveys the wet gypsum board into the drying chamber 11 of the dryer 1. During the process of the gypsum board moving from one end to the other end of the drying chamber 11 driven by the conveyor 12, the hot air in the drying chamber 11 gradually evaporates the moisture in the wet gypsum board. If the conveyor 12 suddenly stops at this time and the gypsum board stays in the drying chamber 11, the control unit will immediately turn off the hot air circulation fan 21 so that the hot air circulation fan 21 no longer conveys hot air into the drying chamber 11, and at the same time, the exhaust fan 22 will be immediately turned on to exhaust the hot air in the drying chamber 11, thereby reducing the temperature in the drying chamber 11 and ensuring that the dihydrate gypsum in the gypsum board core is not excessively dehydrated by the high temperature in the drying chamber 11.

[0026] In an illustrative embodiment, the temperature control unit 2 further includes a first heat exchanger 23. The first heat exchanger 23 includes a first heat exchange channel and a second heat exchange channel. The first heat exchange channel and the second heat exchange channel are both arranged in the first heat exchanger 23. The first heat exchange channel and the second heat exchange channel are separated from each other by a metal wall. Heat exchange can be performed between the fluid flowing through the first heat exchange channel and the fluid flowing through the second heat exchange channel.

[0027] The first heat exchange channel of the first heat exchanger 23 is for water vapor to pass through, and the water vapor is a heat source. The source of the water vapor can be a boiler. One end of the first heat exchange channel is an inlet end, and the other end is an outlet end. The water vapor is input into the first heat exchange channel from the inlet end of the first heat exchange channel, and flows out of the first heat exchange channel from the outlet end after flowing through the first heat exchange channel.

[0028] The two ends of the second heat exchange channel of the first heat exchanger 23 are respectively connected to the hot air circulation fan 21 and the drying chamber 11 of the dryer 1, and the hot air circulation fan 21 is connected to the drying chamber 11 of the dryer 1. The hot air circulation fan 21, the drying chamber 11 and the second heat exchange channel form a hot air circulation loop 20. In some embodiments, the air inlet of the hot air circulation fan 21 is connected to the drying chamber 11, and the air outlet of the hot air circulation fan 21 is connected to the second heat exchange channel. The hot air circulation fan 21 transports the air in the drying chamber 11 to the second heat exchange channel. When the hot air circulation fan 21 is in operation, it can drive the air to circulate between the drying chamber 11 and the second heat exchange channel. When the air flows through the second heat exchange channel, the water vapor flowing through the first heat exchange channel heats the air flowing through the second heat exchange channel.

[0029] In this way, water vapor is introduced into the first heat exchange channel of the first heat exchanger 23, and the water vapor can heat the air flowing through the second heat exchange channel. The hot air circulation fan 21 drives the heated air into the drying chamber 11 to dry the gypsum board.

[0030] In an illustrative embodiment, the temperature control unit 2 also includes a first electric valve 24 and an exhaust gas outlet 101102. The first electric valve 24 may be an electric gate valve. The first electric valve 24 is electrically connected to the control unit. The air outlet of the exhaust fan 22 is connected to the exhaust gas outlet 101102 through a pipeline. The air inlet of the exhaust fan 22 is connected to the hot air circulation loop 20 composed of the hot air circulation fan 21, the drying chamber 11 and the second heat exchange flow channel through the first electric valve 24. One interface of the first electric valve 24 is connected to the air inlet of the exhaust fan 22, and the other interface of the first electric valve 24 may be a pipeline connected between the hot air circulation fan 21 and the drying chamber 11, or a pipeline connected between the second heat exchange flow channel and the drying chamber 11.

[0031] The control unit is configured to open the first electric valve 24 when the conveyor 12 is stopped.

[0032] The first electric valve 24 is usually in a closed state, which can ensure that the hot air in the hot air circulation loop 20 will not leak into the outside environment from the exhaust fan 22 and the exhaust gas outlet 101102 when the conveyor 12 is working normally. When the conveyor 12 stops working, the first electric valve 24 is opened so that the exhaust fan 22 can smoothly exhaust the air in the drying chamber 11.

[0033] In an illustrative embodiment, the temperature control unit 2 further includes a steam electric regulating valve 25. The steam electric regulating valve 25 is disposed upstream of the first heat exchange flow channel of the first heat exchanger 23. The steam electric regulating valve 25 is used to regulate the steam flow rate input into the first heat exchange flow channel of the first heat exchanger 23. In some embodiments, the steam electric regulating valve 25 is disposed between the steam supply pipeline and the first heat exchanger 23.

[0034] The steam electric regulating valve 25 is electrically connected to the control unit, and the control unit is further configured to close the steam electric regulating valve 25 when the conveyor 12 stops.

[0035] In this way, when the conveyor 12 stops, the steam electric regulating valve 25 is closed to cut off the water vapor input into the first heat exchange flow channel of the first heat exchanger 23, disconnect the heat source, avoid energy waste, and also help reduce the temperature in the drying chamber 11.

[0036] In an illustrative embodiment, the drying chamber 11 of the dryer 1 is divided into a plurality of drying zones. The plurality of drying zones are arranged in sequence along the conveying direction of the conveyor 12. The temperature control unit 2 is provided with a plurality of hot air circulation fans 21 of the plurality of temperature control units 2, respectively connected to the plurality of drying zones, and the exhaust fans 22 of the plurality of temperature control units 2, respectively connected to the plurality of drying zones. The hot air circulation fans 21 of the same temperature control unit 2, the first heat exchanger 23 and the drying zones corresponding to the temperature control unit 2 form a hot air circulation loop 20, and the exhaust fan 22 of the temperature control unit 2 is connected to the hot air circulation loop 20.

[0037] In this way, the temperature of each drying zone of the drying chamber 11 is adjusted by a temperature control unit 2, and the temperature adjustment of different positions of the drying chamber 11 can be more accurate. At the same time, multiple exhaust fans 22 can respectively exhaust the air in multiple drying zones, and can quickly cool the drying chamber 11. The internal air temperature of each drying zone of the dryer can be cooled to below 80°C within 20 minutes, and the overburning rate of the gypsum board is 0%.

[0038] In an exemplary embodiment, four drying zones are provided, and the four drying zones are sequentially the first drying zone 111, the second drying zone 112, the third drying zone 113 and the fourth drying zone 114 in the conveying direction of the conveyor 12. Four temperature control units 2 are provided, and the four temperature control units 2 are respectively provided corresponding to the first drying zone 111, the second drying zone 112, the third drying zone 113 and the fourth drying zone 114.

[0039] In this embodiment, the temperature at the air inlet of the first drying zone 111 is 185°C, the temperature at the air outlet of the first drying zone 111 is 130°C, the temperature at the air inlet of the second drying zone 112 is 190°C, the temperature at the air outlet of the second drying zone 112 is 135°C, the temperature at the air inlet of the third drying zone 113 is 150°C, the temperature at the air outlet of the third drying zone 113 is 110°C, the temperature at the air inlet of the fourth drying zone 114 is 130°C, and the temperature at the air outlet of the fourth drying zone 114 is 100°C.

[0040] In an illustrative embodiment, the drying system 100 further includes a heating coil 3. The heating coil 3 is disposed in at least a portion of the drying area. In this embodiment, a heating coil 3 is disposed in each of the third drying area 113 and the fourth drying area 114. The heating coil 3 may be a copper tube. The heating coil 3 is provided for heating water to pass through. When the heating water passes through the heating coil 3, the heating coil 3 can radiate heat to the gypsum board in the drying chamber 11 to accelerate the evaporation of moisture in the gypsum board. The heating water may be 130°C. The heating water may be the water output from the boiler to the heating coil 3, or it may be the condensed water after the water vapor is condensed through the first heat exchanger 23.

[0041] The drying system 100 further includes a water tank 4 and a water pump 9. The water tank 4 is used to hold replacement water. The water temperature of the replacement water in the water tank 4 is lower than the water temperature of the heating water in the heating coil 3. The water inlet of the water pump 9 is connected to the water tank 4 through a pipeline, and the water outlet of the water pump 9 is connected to the heating coil 3 through a pipeline. In this embodiment, the heating coils 3 in the third drying zone 113 and the fourth drying zone 114 are connected in series, and the water outlet of the water pump 9 is connected to one end of the heating coil 3 in the third drying zone 113 that faces away from the heating coil 3 in the fourth drying zone 114. The water pump 9 is electrically connected to the control unit, and the control unit is also configured to turn on the water pump 9 when the conveyor 12 is stopped.

[0042] When the conveyor 12 stops, the water pump 9 can deliver the replacement water in the water storage tank 4 to the heating coil 3 to replace the heating water in the heating coil 3, so that the heating coil 3 can be cooled down quickly to prevent the high-temperature heating coil 3 from overburning the gypsum board.

[0043] In an illustrative embodiment, the water temperature of the replacement water in the water tank 4 is 80° C. A temperature sensor may be provided in the water tank 4, and the water temperature of the replacement water in the water tank 4 is controlled according to the temperature measured by the temperature sensor. For example, a heating device is provided in the water tank 4, and when the water temperature measured by the temperature sensor is lower than 80° C., the heating device heats the replacement water until the water temperature of the replacement water rises to 80° C.

[0044] When the conveyor 12 is stopped, the heating water in the heating coil 3 is replaced with replacement water at 80°C, which can prevent the heating coil 3 from being too hot and overburning the gypsum board, and also prevent the heating coil 3 from being too cold and causing the gypsum board to cool down too quickly and be damaged.

[0045] In an illustrative embodiment, the drying system 100 further includes a flash tank 6 and a second electric valve 31. The flash tank 6 is used to perform gas-liquid separation on the fluid. The flash tank 6 is provided with a mixture inlet 61, a gas outlet 62 and a liquid outlet 63. After the flash tank 6 performs gas-liquid separation on the gas-water mixture input from the mixture inlet 61, the separated water vapor is output from the gas outlet 62, and the separated water is output from the liquid outlet 63. The mixture inlet 61 of the flash tank 6 is connected to the outlet end of at least a portion of the first heat exchange channel. In this embodiment, the outlet end of the first heat exchange channel of the first heat exchanger 23 corresponding to the first drying zone 111, the second drying zone 112, and the third drying zone 113 is connected to the mixture inlet 61 of the flash tank 6.

[0046] The liquid outlet 63 of the flash tank 6 is connected to the inlet of the heating coil 3 in the third drying zone 113, and the second electric valve 31 is arranged on the pipeline between the liquid outlet 63 and the heating coil 3. The second electric valve 31 is electrically connected to the control unit, and the control unit is further configured to close the second electric valve 31 when the conveyor 12 stops.

[0047] When the conveyor 12 of the dryer 1 is running, the second electric valve 31 is in an open state, and the water vapor enters the first heat exchange flow channel of the first heat exchanger 23 corresponding to the first drying area 111, the second drying area 112, and the third drying area 113, and then releases heat and partially condenses to convert into a steam-water mixture. After the steam-water mixture is transported to the flash tank 6, the flash tank 6 performs gas-liquid separation on the steam-water mixture, and the separated water is transported as heating water to the heating coils 3 of the third drying area 113 and the fourth drying area 114 to heat the gypsum board. When the conveyor 12 of the dryer 1 is stopped, the second electric valve 31 is closed, and the flash tank 6 no longer transports heating water to the heating coils 3.

[0048] In an illustrative embodiment, the inlet end of the first heat exchange channel of the first heat exchanger 23 corresponding to the first drying zone 111, the second drying zone 112, and the third drying zone 113 is externally connected to the water vapor supply pipeline, and the inlet end of the first heat exchange channel of the first heat exchanger 23 corresponding to the fourth drying zone 114 is connected to the gas outlet 62 of the flash tank 6.

[0049] In this way, the first heat exchangers 23 corresponding to the first drying zone 111 , the second drying zone 112 , and the third drying zone 113 are supplied with water vapor by the water vapor supply pipeline 200 , and the first heat exchanger 23 corresponding to the fourth drying zone 114 is supplied with water vapor by the flash tank 6 .

[0050] In an illustrative embodiment, the drying system 100 further includes a second heat exchanger 7, a condensed water tank 5 and a preheating fan 7. The second heat exchanger 7 includes a third heat exchange channel and a fourth heat exchange channel. The inlet end of the third heat exchange channel is connected to the liquid outlet 63 of the flash tank 6, and the outlet end of the third heat exchange channel is connected to the second electric valve 31.

[0051] The inlet end of the fourth heat exchange channel of the second heat exchanger 7 is connected to the air outlet of the preheating fan 7 , and the inlet end of the fourth heat exchange channel of the second heat exchanger 7 is connected to the hot air circulation loop 20 corresponding to the first drying area 111 and the second drying area 112 .

[0052] The condensed water tank 5 is provided with a first water inlet 52, a second water inlet 51, a first water outlet 53 and a second water outlet 54. The outlet end of the first heat exchange channel of the first heat exchanger 23 corresponding to the fourth drying zone 114 is connected to the first water inlet 52 of the condensed water tank 5. The outlet of the heating coil 3 in the fourth drying zone 114 is connected to the second water inlet 51 of the condensed water tank 5.

[0053] The water storage tank 4 is provided with a third water inlet 41 and a third water outlet 42. The third water inlet 41 of the water storage tank 4 is connected to the first water outlet 53 of the condensed water tank 5. The third water outlet 42 of the water storage tank 4 is connected to the water inlet of the water pump 9.

[0054] In this way, the heating water output from the liquid outlet 63 of the flash tank 6 first enters the third heat exchange channel of the second heat exchanger 7, flows through the third heat exchange channel, enters the heating coil 3, and then enters the condensate tank 5. Part of the water in the condensate tank 5 enters the water storage tank 4 to replenish the water storage tank 4, and the other part of the water in the condensate tank 5 flows back to the boiler through the second water outlet 54.

[0055] The preheating fan 7 can transport air in the environment to the fourth heat exchange channel of the second heat exchanger 7. When the air flows through the fourth heat exchange channel, it exchanges heat with the heating water in the third heat exchange channel of the second heat exchanger 7 and is heated. The high-temperature air then enters the hot air circulation loop 20 corresponding to the first drying area 111 and the second drying area 112.

[0056] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0057] In addition, the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first", "second", etc. may explicitly or implicitly include at least one of the features.

[0058] In the description of the present application, “plurality” means at least two, for example, two, three, etc., unless otherwise clearly and specifically defined.

[0059] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0060] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0061] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0062] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A drying system, characterized in that: include: The dryer comprises a furnace body with a drying chamber therein and a conveyor passing through the drying chamber; Temperature control unit, including: A hot air circulation fan connected to the drying chamber and used for delivering heated air to the drying chamber; An exhaust fan connected to the drying chamber and used to discharge the air in the drying chamber to outside the furnace; A control unit electrically connected to the conveyor, the hot air circulation fan and the exhaust fan; Wherein, the control unit is configured to turn off the hot air circulation fan and turn on the exhaust fan when the conveyor stops.

2. The drying system according to claim 1, characterized in that: The temperature control unit also includes a first heat exchanger; The first heat exchanger includes a first heat exchange channel and a second heat exchange channel; Among them, the first heat exchange flow channel is used for water vapor to pass through, and the two ends of the second heat exchange flow channel are respectively connected to the hot air circulation fan and the drying chamber, so that the hot air circulation fan, the drying chamber and the second heat exchange flow channel form a hot air circulation loop, and the water vapor flowing through the first heat exchange flow channel heats the air flowing through the second heat exchange flow channel.

3. The drying system according to claim 2, characterized in that: The temperature control unit also includes a first electric valve electrically connected to the control unit; The air inlet of the exhaust fan is connected to the hot air circulation loop through the first electric valve; The control unit is configured to open the first electric valve when the conveyor stops.

4. The drying system according to claim 2, characterized in that: The temperature control unit further comprises a steam electric regulating valve disposed upstream of the first heat exchange flow channel, the steam electric regulating valve being used to regulate the steam flow input into the first heat exchange flow channel; The steam electric regulating valve is electrically connected to the control unit, and the control unit is further configured to close the steam electric regulating valve when the conveyor stops.

5. The drying system according to any one of claims 2 to 4, characterized in that: The drying chamber is divided into a plurality of drying zones, and the plurality of drying zones are arranged in sequence along the conveying direction of the conveyor; The temperature control units are provided in plurality, and the hot air circulation fans of the plurality of temperature control units are respectively connected to the plurality of drying areas, and the exhaust fans of the plurality of temperature control units are respectively connected to the plurality of drying areas.

6. The drying system according to claim 5, characterized in that: It also includes a heating coil, which is arranged in at least a part of the drying area and through which heating water passes; The drying system also includes a water storage tank for holding replacement water and a water pump communicating between the water storage tank and the heating coil; Among them, the water temperature of the replacement water is lower than the water temperature of the heating water in the heating coil, the water pump is used to pump the replacement water in the water storage tank to the heating coil, the water pump is electrically connected to the control unit, and the control unit is also configured to turn on the water pump when the conveyor stops.

7. The drying system according to claim 6, characterized in that: The temperature of the replacement water is 80°C.

8. The drying system according to claim 6, characterized in that: Also included are the flash tank and second electric valve; The flash tank is provided with a mixture inlet, a gas outlet and a liquid outlet. The flash tank is used to perform gas-liquid separation on the gas-water mixture input from the mixture inlet, output the separated water vapor from the gas outlet, and output the separated water from the liquid outlet; The mixture inlet is connected to the outlet end of at least a portion of the first heat exchange flow channel, the liquid outlet is connected to the inlet of the heating coil, and the second electric valve is arranged on the pipeline between the liquid outlet and the heating coil; The second electric valve is electrically connected to the control unit, and the control unit is further configured to close the second electric valve when the conveyor stops.

9. The drying system according to claim 8, characterized in that: There are four drying zones, which are the first drying zone, the second drying zone, the third drying zone and the fourth drying zone in the conveying direction of the conveyor; The inlet ends of the first heat exchange channels of the first heat exchangers corresponding to the first drying zone, the second drying zone and the third drying zone are externally connected to the water vapor supply pipeline, and the inlet end of the first heat exchange channel of the first heat exchanger corresponding to the fourth drying zone is connected to the gas outlet.

10. The drying system according to claim 9, characterized in that: It also includes a second heat exchanger, a condensate tank and a preheating fan; The second heat exchanger includes a third heat exchange channel and a fourth heat exchange channel; The inlet end of the third heat exchange flow channel is connected to the liquid outlet, and the outlet end of the third heat exchange flow channel is connected to the second electric valve; The inlet end of the fourth heat exchange channel is connected to the air outlet of the preheating fan, and the inlet end of the fourth heat exchange channel is connected to the hot air circulation loops corresponding to the first drying area and the second drying area; The condensed water tank is provided with a first water inlet, a second water inlet, a first water outlet and a second water outlet, the outlet end of the first heat exchange channel of the first heat exchanger corresponding to the fourth drying zone is connected to the first water inlet, and the outlet of the heating coil is also connected to the second water inlet; The water storage tank is provided with a third water inlet connected to the first water outlet and a third water outlet connected to the water inlet of the water pump.

Images