System for improving heat efficiency of dryer

Abstract

The utility model discloses a system for improving the heat efficiency of a dryer, and relates to the technical field of waste heat recovery, the system comprises a dryer, a steam pipe and a damp and hot waste gas waste heat recoverer, the periphery of the dryer is provided with a heat insulation cover, a plurality of rollers are arranged in the dryer, fabric is tensioned on the surfaces of the rollers, and heat transfer is carried out between the fabric and the rollers; steam enters the roller through the steam pipe; the humid and hot waste gas waste heat recoverer is used for receiving humid and hot air generated by cloth evaporation and conducting heat interaction with the introduced air. Heat of waste gas exhausted by the system can be recycled, and the drying efficiency of the system can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of waste heat recovery, in particular to a system for improving the thermal efficiency of a drying machine. Background Art

[0002] The energy consumption of the printing and dyeing industry is mainly composed of thermal energy (steam), which is mainly used for drying, washing, steaming, high-temperature heat treatment and others. The drying process is a necessary link in the fabric printing and dyeing process. A large amount of energy is consumed in this link, accounting for more than 30% of the total energy consumption of the entire printing and dyeing production line. However, there are many problems in the drying process of fabrics: (1) The exhaust gas discharged by the system is often directly discharged into the atmosphere, and the heat it takes away accounts for about 43% of the total energy consumption of the drying process; (2) For textile factories with low hot water demand, condensed water only recycles water but not heat, and the heat is directly dissipated in the environment; (3) The humidity of the humid air discharged by the dryer is either too low, resulting in energy waste, or too high, affecting the drying efficiency; (4) The humidity of the fabric outlet is based on the feel, and there is a phenomenon of "overdrying". Utility Model Content

[0003] In view of the shortcomings of large heat loss and low drying efficiency of waste heat recovery of printing and dyeing dryers in the prior art, the utility model provides a system for improving the thermal efficiency of the dryer, which can recover the heat of the waste gas discharged by the system and improve the drying efficiency of the system.

[0004] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0005] A system for improving the thermal efficiency of a dryer, comprising:

[0006] A dryer, the outer periphery of which is provided with a heat preservation cover, wherein a plurality of rollers are provided inside the dryer, and the fabric is stretched on the surface of the plurality of rollers and heat is transferred to the fabrics;

[0007] a steam pipe through which steam enters the drum; and,

[0008] The wet hot exhaust gas waste heat recovery device is used to receive the wet hot air generated by the evaporation of the fabric and perform thermal interaction with the incoming air.

[0009] The system for improving the thermal efficiency of the dryer as described above further includes an exhaust pipe, wherein the exhaust pipe includes a first exhaust pipe section and a second exhaust pipe section, wherein the air inlet end of the first exhaust pipe section is connected to the top of the thermal insulation cover, and the air outlet end of the first exhaust pipe section is connected to the first air inlet side of the wet heat exhaust gas waste heat recovery device; the air inlet end of the second exhaust pipe section is connected to the first air outlet side of the wet heat exhaust gas waste heat recovery device, and the air outlet end of the second exhaust pipe section is connected to a washing tower.

[0010] The system for improving the thermal efficiency of the dryer as described above, further, the second exhaust pipe section is provided with an exhaust fan.

[0011] The system for improving the thermal efficiency of the dryer as described above further includes an air intake pipe, which includes a first air intake pipe section and a second air intake pipe section, wherein the air intake end of the first air intake pipe section is connected to the second air outlet side of the moist heat exhaust gas waste heat recovery device, and the air outlet end of the first air intake pipe section is connected to the bottom of the thermal insulation cover; the air outlet end of the second air intake pipe section is connected to the second air intake side of the moist heat exhaust gas waste heat recovery device.

[0012] The system for improving the thermal efficiency of the dryer as described above, further, the second air intake pipe section is provided with an air intake fan.

[0013] The system for improving the thermal efficiency of the dryer as described above further includes a condensing water pipe, the water inlet end of the condensing water pipe is connected to the drum, and the water outlet end of the condensing water pipe is discharged from the system through a high-temperature water source heat pump.

[0014] As described above, the system for improving the thermal efficiency of the dryer, further, the high-temperature water source heat pump is also connected to a steam exhaust pipe, the steam exhaust pipe is connected to the steam application module, the steam exhaust pipe is provided with a steam flow meter, the steam application module is also provided with a main steam pipe, and the main steam pipe is provided with a main steam valve.

[0015] As described above, the system for improving the thermal efficiency of the dryer further has a plurality of correspondingly arranged aeration plates distributed on the air outlet end of the first air inlet pipe section, and the plurality of aeration plates are arranged below the plurality of drums.

[0016] The system for improving the thermal efficiency of the dryer as described above further includes:

[0017] Logic controller;

[0018] The fabric moisture probe, air humidity infrared probe, exhaust fan inverter, air inlet inverter and dryer inverter connected to the control signal of the logic controller,

[0019] Among them, the exhaust fan inverter is used to adjust the operating frequency of the exhaust fan; the intake fan inverter is used to adjust the operating frequency of the intake fan; the dryer inverter is used to adjust the operating frequency of the dryer, the fabric moisture content probe is used to detect the moisture content of the fabric, the air humidity infrared probe is used to detect the humidity of the humid and hot exhaust gas, and the logic controller receives feedback signals from the fabric moisture content probe and the air humidity infrared probe to control the output frequencies of the exhaust fan inverter, the intake fan inverter and the dryer inverter.

[0020] The system for improving the thermal efficiency of the dryer as described above further includes: a steam flow meter and a main steam valve connected to the control signal of the logic controller, wherein the steam flow meter is used to detect the steam flow of the high-temperature water source heat pump, and the logic controller receives the feedback signal of the steam flow meter to control the opening of the main steam valve.

[0021] Compared with the prior art, the utility model has the following beneficial effects: the humidity of the cloth at the outlet of the dryer, the humidity of the humid air and the waste heat recovery are integrated and optimized, which can effectively avoid the phenomenon of over-drying of the cloth, and can effectively prevent the exhaust gas from taking away too much heat or the exhaust gas humidity from being too high, resulting in reduced drying efficiency. Using the humid and hot exhaust gas to heat the fresh air not only reduces the steam consumption of the dryer, but also accelerates the drying efficiency, and recovers the heat of condensed water to produce steam, which can effectively reduce the steam consumption of the enterprise. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 This is a schematic diagram of the structure of the system for improving the thermal efficiency of the dryer in the embodiment of the utility model.

[0024] Figure 2 This is a control principle diagram of a system for improving the thermal efficiency of a dryer in an embodiment of the utility model.

[0025] Explanation of the reference numerals: 1. Dryer; 2. Drum; 3. Wet and hot exhaust gas waste heat recovery device; 4. High-temperature water source heat pump; 5. Exhaust fan; 6. Intake fan; 7. Steam flow meter; 8. Fabric moisture content probe; 9. Air humidity infrared probe; 10. Steam valve; 11. Scrubber; 12. Insulation cover. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0027] Example:

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the utility model and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the utility model described here can be implemented in an order other than those illustrated or described here. In addition, the terms "including" and "having" in the embodiments of the utility model and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] In the description of the present invention, "multiple" means at least two, such as two, three, etc., unless otherwise clearly defined. In addition, unless otherwise clearly defined and defined, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it 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 it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] To solve the problem that the exhaust gas discharged from the system is often directly discharged into the atmosphere, the heat it takes away accounts for about 43% of the total energy consumption of the drying process. For textile factories with low demand for hot water, the condensed water only recycles water but not heat. The heat is directly dissipated in the environment, resulting in large heat loss in the waste heat recovery of the printing and dyeing dryer and low drying efficiency.

[0031] See also Figure 1 , a system for improving the thermal efficiency of a dryer provided by an embodiment of the utility model comprises: a dryer 1, a steam pipe and a humid heat exhaust gas waste heat recovery device 3. Specifically, a heat preservation cover 12 is provided on the outer periphery of the dryer 1, and a plurality of drums 2 are provided in the dryer 1. The fabric is stretched on the surface of the plurality of drums 2. The fabric moves forward at a certain speed, and the moisture on the fabric is evaporated by the steam heat in the drum 22; the steam enters the drum 2 through the steam pipe; the humid heat exhaust gas waste heat recovery device 3 is used to receive the humid heat air generated by the evaporation of the fabric, and to perform thermal interaction with the incoming air. The fabric can be cotton yarn. Furthermore, the humid heat exhaust gas waste heat recovery device 3 uses the humid heat exhaust gas discharged by the dryer 1 as a heat source to heat fresh air, and the fresh air is fed into the dryer 1 from the bottom of the dryer 1.

[0032] Through the system provided in this embodiment, the heat of the exhaust gas discharged by the system can be recovered, which can effectively prevent the exhaust gas from taking away too much heat. The heat of the humid exhaust gas is used to heat the fresh air, which not only reduces the steam consumption of the dryer 1, but also accelerates the drying speed of the dryer 1, thereby improving the drying efficiency of the dryer 1.

[0033] In the above embodiment, the wet and hot waste heat recovery device 3 is used to receive the wet and hot air generated by the evaporation of the cloth and to perform thermal interaction with the incoming air. The specific implementation form can be: including an exhaust pipe and an intake pipe, specifically, the exhaust pipe includes a first exhaust pipe section and a second exhaust pipe section, the intake end of the first exhaust pipe section is connected to the top of the thermal insulation cover 12, and the outlet end of the first exhaust pipe section is connected to the first intake side of the wet and hot waste heat recovery device 3; the intake end of the second exhaust pipe section is connected to the first outlet side of the wet and hot waste heat recovery device 3, and the outlet end of the second exhaust pipe section is connected to the washing tower 11. After the wet and hot waste gas recovers the waste heat, it is sprayed and dust-removed through the washing tower 11 and then discharged. Furthermore, an exhaust fan 5 is provided on the second exhaust pipe section. The air inlet pipe includes a first air inlet pipe section and a second air inlet pipe section, the air inlet end of the first air inlet pipe section is connected to the second air outlet side of the wet and hot waste gas waste heat recovery device 3, and the air outlet end of the first air inlet pipe section is connected to the bottom of the thermal insulation cover 12; the air outlet end of the second air inlet pipe section is connected to the second air inlet side of the wet and hot waste gas waste heat recovery device 3. Further, a plurality of correspondingly arranged aeration plates are distributed on the air outlet end of the first air inlet pipe section, and a plurality of the aeration plates are arranged under a plurality of the drums 2. Further, an air inlet fan 6 is provided on the second air inlet pipe section. Further, the wet and hot waste gas needs to be filtered through a filter before passing to the wet and hot waste gas waste heat recovery device 3.

[0034] In one embodiment, the system may further include a condensate pipe, the water inlet end of the condensate pipe is connected to the drum 2, and the water outlet end of the condensate pipe is discharged from the system through the high-temperature water source heat pump 4. Furthermore, the high-temperature water source heat pump 4 is also connected to a steam discharge pipe, and the steam discharge pipe is connected to a steam application module. The steam application module can be a process such as sizing with low steam demand. The steam discharge pipe is provided with a steam flow meter 7, and the steam application module is also provided with a main steam pipe, and the main steam pipe is provided with a main steam valve 10. The high-temperature water source heat pump 4 uses the condensate from the steam trap of the dryer 1 to produce low-temperature steam, and the obtained low-temperature steam is led to processes such as sizing with low steam demand. Through the system provided in this embodiment, the heat of condensate can be recovered to produce steam, which can effectively reduce the steam consumption of the enterprise.

[0035] See also Figure 2In order to solve the problem that the humidity of the wet air discharged by the dryer 1 is either too low, causing energy waste, or too high, affecting the drying efficiency and the fabric outlet humidity, and there is a phenomenon of "over-drying", in one embodiment, the system also includes a logic controller and a fabric moisture content probe 8, an air humidity infrared probe 9, an exhaust fan inverter, an intake fan inverter and a dryer inverter connected to the control signal of the logic controller. Specifically, the exhaust fan inverter is used to adjust the operating frequency of the exhaust fan 5; the intake fan inverter is used to adjust the operating frequency of the intake fan 6; the dryer inverter is used to adjust the operating frequency of the dryer 1, the fabric moisture content probe 8 is used to detect the moisture content of the fabric, and the air humidity infrared probe 9 is used to detect the humidity of the humid and hot exhaust gas. The logic controller receives the feedback signals of the fabric moisture content probe 8 and the air humidity infrared probe 9, and controls the output frequencies of the exhaust fan inverter, the intake fan inverter and the dryer inverter.

[0036] The above embodiment further includes: a steam flow meter 7 and a main steam valve 10 connected to the control signal of the logic controller, wherein the steam flow meter 7 is used to detect the steam flow of the high-temperature water source heat pump 4, and the logic controller receives the feedback signal of the steam flow meter 7 to control the opening of the main steam valve 10.

[0037] For example, at the outlet of the dryer 1, three fabric moisture content probes 8 are provided above the fabric, respectively arranged at the left, middle and right positions of the fabric plane, and their signals are given to the frequency converter to control the speed of the dryer 1. Two air humidity infrared probes 9 are provided near the wet and hot exhaust gas discharge port above the thermal insulation cover 12, and their signals are given to the fan frequency converter to adjust the air intake volume of the air intake fan 6 and the exhaust volume of the exhaust fan 5. A steam flow meter 7 is provided at the outlet of the high-temperature water source heat pump 4, and its signal is given to the main steam valve 10 for sizing and other processes to control the switch of the main steam valve 10.

[0038] Through the system provided in this embodiment, the humidity of the cloth at the outlet of the dryer 1, the humidity of the humid air and the waste heat recovery are integrated and optimized. At the same time, the humidity is detected by respective sensors, which can effectively avoid the phenomenon of over-drying of the cloth and effectively prevent the exhaust gas from taking away too much heat or the exhaust gas humidity from being too high, resulting in reduced drying efficiency.

[0039] The following describes the working process, including:

[0040] When the fabric moisture content probe detects that the fabric moisture content is less than the set value, the dryer inverter is instructed to increase the output frequency until the fabric moisture content reaches the set value; when the fabric moisture content probe detects that the fabric moisture content is greater than the set value, the dryer inverter is instructed to reduce the output frequency until the fabric moisture reaches the set value;

[0041] When the humidity of the hot and humid exhaust gas detected by the air humidity infrared probe 9 is lower than the set value, the exhaust fan inverter and the intake fan inverter are instructed to reduce the output frequency; when the humidity of the hot and humid exhaust gas detected by the air humidity infrared probe 9 is higher than the set value, the exhaust fan inverter and the intake fan inverter are instructed to increase the output frequency;

[0042] When the steam flow meter 7 detects that the steam flow of the high-temperature water source heat pump 4 is greater than the set value, the main steam valve 10 of the steam application module is closed; when the steam flow meter 7 detects that the steam flow of the high-temperature water source heat pump 4 is lower than the set value, the main steam valve 10 of the steam application module is opened.

[0043] Exemplarily, when the fabric moisture content probe 8 detects that the moisture content of the fabric is less than a set value, the speed of the dryer 1 is increased until the moisture content of the fabric reaches the set value; when the fabric moisture content probe 8 detects that the moisture content of the fabric is greater than the set value, the speed of the dryer 1 is slowed down until the moisture content of the fabric reaches the set value.

[0044] When the humidity of the hot and humid exhaust gas detected by the air humidity infrared probe 9 is lower than the set value, the rotation speed of the air intake fan 6 and the exhaust fan 5 is reduced; when the humidity of the hot and humid exhaust gas detected by the air humidity infrared probe 9 is higher than the set value, the rotation speed of the air intake fan 6 and the exhaust fan 5 is increased.

[0045] When the steam flow meter 7 detects that the steam flow of the high-temperature heat pump is greater than the set value, the main steam valve 10 of the process using low-pressure steam is closed; when the steam flow meter 7 detects that the steam flow of the high-temperature heat pump is lower than the set value, the main steam valve 10 of the process using low-pressure steam is opened.

[0046] The set value of the fabric moisture content is set according to the fabric type. In this embodiment, the moisture content of the cotton yarn is set between 8% and 10%.

[0047] In order to effectively reduce the energy consumption of drying, the humidity of the hot and humid exhaust gas in this embodiment is controlled between 45% and 50%.

[0048] 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 invention 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 invention.

[0049] In the present utility model, 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" or "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" or "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.

[0050] 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 utility model. 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.

[0051] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable ordinary technicians in the field to understand the content of the utility model and implement it accordingly, and they cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the essence of the content of the utility model should be included in the protection scope of the utility model.

Claims

1. A system for improving the thermal efficiency of a dryer, characterized in that: include: A dryer, the outer periphery of which is provided with a heat preservation cover, wherein a plurality of rollers are provided inside the dryer, and the fabric is stretched on the surface of the plurality of rollers and heat is transferred to the fabrics; a steam pipe through which steam enters the drum; and, A wet and hot waste gas heat recovery device, which is used to receive the wet and hot air generated by the evaporation of the fabric and perform thermal interaction with the incoming air; An exhaust pipe, the exhaust pipe comprising a first exhaust pipe section and a second exhaust pipe section, the air inlet end of the first exhaust pipe section being connected to the top of the heat preservation cover, the air outlet end of the first exhaust pipe section being connected to the first air inlet side of the wet and hot exhaust gas waste heat recovery device; the air inlet end of the second exhaust pipe section being connected to the first air outlet side of the wet and hot exhaust gas waste heat recovery device, the air outlet end of the second exhaust pipe section being connected to a scrubbing tower; The second exhaust pipe section is provided with an exhaust fan; The air intake pipe includes a first air intake pipe section and a second air intake pipe section, the air intake end of the first air intake pipe section is connected to the second air outlet side of the wet and hot exhaust gas waste heat recovery device, the air outlet end of the first air intake pipe section is connected to the bottom of the heat preservation cover; the air outlet end of the second air intake pipe section is connected to the second air intake side of the wet and hot exhaust gas waste heat recovery device; The second air intake pipe section is provided with an air intake fan; Logic controller; The fabric moisture probe, air humidity infrared probe, exhaust fan inverter, air inlet inverter and dryer inverter connected to the control signal of the logic controller, Among them, the exhaust fan inverter is used to adjust the operating frequency of the exhaust fan; the intake fan inverter is used to adjust the operating frequency of the intake fan; the dryer inverter is used to adjust the operating frequency of the dryer, the fabric moisture content probe is used to detect the moisture content of the fabric, the air humidity infrared probe is used to detect the humidity of the humid and hot exhaust gas, and the logic controller receives feedback signals from the fabric moisture content probe and the air humidity infrared probe to control the output frequencies of the exhaust fan inverter, the intake fan inverter and the dryer inverter.

2. The system for improving the thermal efficiency of a dryer according to claim 1, characterized in that: It also includes a condensing water pipe, the water inlet end of the condensing water pipe is connected to the drum, and the water outlet end of the condensing water pipe passes through a high-temperature water source heat pump discharge system.

3. The system for improving the thermal efficiency of a dryer according to claim 2, characterized in that: The high-temperature water source heat pump is also connected to a steam exhaust pipe, which is connected to a steam application module. A steam flow meter is provided on the steam exhaust pipe. The steam application module is also provided with a main steam pipe, which is provided with a main steam valve.

4. The system for improving the thermal efficiency of a dryer according to claim 1, characterized in that: A plurality of corresponding aeration plates are distributed on the air outlet end of the first air inlet pipe section, and the plurality of aeration plates are arranged below the plurality of rollers.

5. The system for improving the thermal efficiency of a dryer according to claim 1, characterized in that: Also includes: A steam flow meter and a main steam valve connected to the control signal of the logic controller, wherein the steam flow meter is used to detect the steam flow of the high-temperature water source heat pump, and the logic controller receives the feedback signal of the steam flow meter to control the opening of the main steam valve.

Images