A waste heat recovery system and method for a flat press exhaust duct

Abstract

The application discloses a waste heat recovery system and method for a waste pipe of a flat iron, and the system comprises an economizer and a control system; the economizer comprises a cylindrical shell, upper and lower end covers are arranged at upper and lower ends of the cylindrical shell respectively, the upper and lower end covers are in sealing connection with the cylindrical shell, a cooling water inlet pipe and a waste gas outlet are arranged on the upper end cover, a water vapor separation module and a multi-stage heat recovery module are arranged in the cylindrical shell, and temperature acquisition modules are arranged on the cooling water inlet pipe, the waste gas outlet, a waste gas inlet, a hot water outlet pipe and a condensate water drain pipe; the control system is connected with the economizer, and the economizer is controlled according to temperature information. The concentrated waste heat is transferred, a high-temperature heat source with a small cross section is transferred layer by layer, then the heat energy is utilized, water passing through another channel of the pipe is gradually heated, and the water temperature can reach nearly 70 DEG C after being heated step by step.

Description

Technical Field

[0001] This invention relates to the field of waste heat recovery technology, and in particular to a waste heat recovery system and method for the waste discharge pipe of a flat ironing machine. Background Technology

[0002] In the laundry industry, there is a type of equipment called a flat ironing machine, which is an essential piece of equipment for washing hotel bed sheets, quilts, and pillowcases. This equipment plays a crucial role in the laundry industry and is also a major energy consumer. If calculated as a percentage of energy input in the laundry industry, this equipment accounts for nearly 30% of the energy consumption of a laundry company.

[0003] Most laundry services now use natural gas to generate steam, employing high-temperature steam from natural gas boilers as a heat source to power various heat-consuming equipment, such as ironing machines, dryers, and washing machines. According to our research and on-site data collection, the steam inlet pressure of a typical ironing machine is 0.6 MPa-0.8 MPa. Between MPa, the saturation temperature of the inlet steam is approximately 170℃ (dry steam). After the ironing process by the flat ironing machine, the machine discharges low-temperature steam (wet steam) containing a large amount of moisture at a temperature of approximately 95℃ through a waste discharge pipe with a diameter of approximately 300mm. According to actual measurements, the waste steam discharged from the waste discharge pipe with a diameter of approximately 300mm has a high moisture content. In summer, no smoke is visible at the waste discharge outlet, but in winter, a large amount of white water vapor can be seen being discharged from the outlet. The temperature measured at the top of the waste discharge pipe with a diameter of approximately 300mm is approximately 93℃. After in-depth analysis of the working principle of the flat ironing machine, it is basically impossible to directly recover heat energy from the pipe using traditional methods, and this would also affect the flat ironing machine. In order to achieve efficient recovery and utilization of waste heat and water vapor in the waste discharge pipe of the flat ironing machine, this application is hereby proposed. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a waste heat recovery system and method for the waste exhaust pipe of a flat ironing machine. This system transfers concentrated waste heat to achieve efficient utilization of waste heat. At the same time, a corresponding condensate recovery module is designed to prevent water in the waste steam from flowing back into the flat ironing machine and affecting the ironing effect.

[0005] In a first aspect, this application provides a waste heat recovery system for the waste discharge pipe of a flat ironing machine, including an energy saver and a control system;

[0006] The energy-saving device includes a cylindrical shell with an upper end cover and a lower end cover at its upper and lower ends, respectively. The upper and lower end covers are sealed to the cylindrical shell. A cooling water inlet pipe and an exhaust gas outlet are provided on the upper end cover, and the cooling water inlet pipe and exhaust gas outlet penetrate the upper end cover. An exhaust gas inlet, a hot water outlet pipe, and a condensate drain pipe are provided on the lower end cover, and the exhaust gas inlet pipe, hot water outlet pipe, and condensate drain pipe penetrate the lower end cover. A water vapor separation module and a multi-stage heat recovery module are provided inside the cylindrical shell. The water vapor separation module is located at the end near the lower end cover, and the multi-stage heat recovery module is located at the end near the upper end cover. The multi-stage heat recovery module is connected to the cooling water inlet pipe and the hot water outlet pipe.

[0007] Temperature acquisition modules are installed on the cooling water inlet pipe, exhaust steam outlet, exhaust steam inlet, hot water outlet pipe, and condensate drain pipe.

[0008] The control system is connected to the energy saver and is used to acquire temperature information collected in real time by the temperature acquisition module. The temperature information includes the water temperature of the cooling water inlet pipe, the water temperature of the hot water outlet pipe, the water temperature of the condensate drain pipe, the exhaust steam temperature at the exhaust steam outlet, and the exhaust steam temperature at the exhaust steam inlet. The control system controls the energy saver based on the temperature information.

[0009] Furthermore, the condensate drain pipe includes a condensate inlet end and a condensate outlet end. The condensate inlet end is the end closest to the water vapor separation module, and the condensate inlet end is not higher than the inner side of the lower end cover.

[0010] Furthermore, the energy saver also includes a condensate redistribution module, which includes a level detection module, a suction device, a storage device, and a pumping device. The suction device is connected to the condensate drain pipe. The level detection module is installed on the lower end cover to detect the level of condensate in the lower end cover. The storage device is used to store condensate, and the pumping device is connected to the storage device.

[0011] Furthermore, the water vapor separation module is disposed inside a cylindrical shell and located above the exhaust gas inlet. The water vapor separation module consists of a first separation umbrella and several second separation umbrellas arranged sequentially along the axial direction of the cylindrical shell.

[0012] The top of the first separation umbrella is close to the multi-stage heat recovery module, and no vent is provided in the center. The size of the first separation umbrella is smaller than the size of the adjacent second separation umbrella.

[0013] Several second separation umbrellas are located below the first separation umbrella, with a vent in the center;

[0014] Along the direction away from the multi-stage heat recovery module, the lower circumferential diameter and the vent diameter of the second separation umbrella gradually decrease and increase, with the lower circumferential diameter of the second separation umbrella closer to the exhaust gas inlet being larger than the diameter of the exhaust gas inlet.

[0015] Furthermore, the water vapor separation module includes two second separation umbrellas. The first separation umbrella and the second separation umbrella are connected by a support rod, and the second separation umbrella near the exhaust gas inlet is connected to the lower end cover by a support rod.

[0016] Furthermore, the multi-stage heat recovery and utilization module consists of several heat exchange modules, each heat exchange module having a heat exchange medium inlet end and a heat exchange medium outlet end.

[0017] Furthermore, the multi-stage heat recovery and utilization module consists of four heat exchange modules connected in series. The four heat exchange modules are a first-stage heat exchange module, a second-stage heat exchange module, a third-stage heat exchange module, and a fourth-stage heat exchange module. The heat exchange medium inlet end of the first-stage heat exchange module is connected to the cooling water inlet pipe, the heat exchange medium outlet end of the first-stage heat exchange module is connected to the heat exchange medium inlet end of the second-stage heat exchange module, the heat exchange medium outlet end of the second-stage heat exchange module is connected to the heat exchange medium inlet end of the third-stage heat exchange module, the heat exchange medium outlet end of the third-stage heat exchange module is connected to the heat exchange medium inlet end of the fourth-stage heat exchange module, and the heat exchange medium outlet end of the fourth-stage heat exchange module is connected to the hot water outlet pipe.

[0018] Furthermore, the outer contours of the heat exchange tubes arranged within the first-stage heat exchange module, the second-stage heat exchange module, the third-stage heat exchange module, and the fourth-stage heat exchange module are rectangles of the same size.

[0019] Furthermore, the number of heat exchange tubes in the first-stage heat exchange module is: N The cross-sectional area of ​​the heat exchange tube is s The number of heat exchange tubes in the second-stage heat exchange module is: N / 2, the cross-sectional area of ​​the heat exchange tube is 2 s The number of heat exchange tubes in the third-stage heat exchange module is: N / 3, the heat exchanger tube cross-sectional area is 3 s The number of heat exchange tubes in the fourth-stage heat exchange module is N / 4, the heat exchanger tube cross-sectional area is 4 s .

[0020] Furthermore, a controllable valve is installed at the inlet of the cooling water inlet pipe or the heat exchange medium inlet of the first-stage heat exchange module. The control system adjusts the controllable valve according to the temperature information to regulate the flow rate of the cooling water.

[0021] Secondly, this application provides a waste heat recovery method for the waste discharge pipe of a flat ironing machine, employing a waste heat recovery system for the waste discharge pipe of a flat ironing machine, comprising the following steps:

[0022] Step 1: The exhaust steam from the flat iron's exhaust pipe enters the economizer through the exhaust steam inlet on the lower end cover, and the control system collects the exhaust steam temperature at the exhaust steam inlet.

[0023] Step 2: The control system determines whether to activate the economizer based on the exhaust gas inlet temperature.

[0024] When the temperature of the exhaust gas at the inlet is greater than or equal to the preset temperature, the economizer will be turned on. The preset temperature is calculated based on the average temperature of the exhaust gas discharged during the ironing operation of the flat iron.

[0025] If the exhaust gas inlet temperature is less than the preset temperature, return to step 1;

[0026] Step 3: Temperature Information Acquisition

[0027] Collect the water temperature in the cooling water inlet pipe;

[0028] The waste gas entering the energy saver passes through the water vapor separation module and the multi-stage heat recovery and utilization module in sequence. The water vapor in the waste gas is condensed and collected in the lower end cover through the water vapor separation module, and discharged through the condensate drain pipe. The water temperature of the condensate drain pipe is collected.

[0029] The exhaust gas enters the economizer through the exhaust gas inlet, and the temperature of the exhaust gas at the exhaust gas inlet is collected.

[0030] The high-temperature waste gas, after passing through the multi-stage heat recovery and utilization module, heats the cooling water through gradient amplification heating, thereby realizing the utilization of waste gas heat. The hot water that has absorbed the heat of the waste gas is discharged from the hot water outlet pipe on the lower end cover, and the water temperature of the hot water outlet pipe is collected.

[0031] The exhaust gas that has released heat is discharged from the exhaust gas outlet on the upper end cover, and the exhaust gas temperature at the exhaust gas outlet is collected.

[0032] Step 4: The control system adjusts the energy saver based on the temperature information collected in Step 3 to ensure that the hot water outlet temperature reaches 55℃-70℃.

[0033] The beneficial effects of this invention are as follows:

[0034] (1) The system of the present invention transfers the concentrated waste heat, and transmits the high temperature heat source with a very small cross section through layers. Then, it uses this heat energy to gradually heat the water in another channel of the pipe. After the water is heated step by step, the water temperature can reach nearly 70°C. Therefore, after adopting this system, as long as the ironing machine is turned on, there will be a continuous supply of hot water. This not only makes use of the waste heat discharged by the ironing machine and saves the cost of natural gas for heating hot water, but also reduces the temperature of the waste discharge pipe, reduces the amount of waste white smoke emitted when the ironing machine is running, reduces the urban heat island effect, and reduces the pressure on urban environmental protection.

[0035] (2) The water and gas in the waste gas are classified by the water vapor separation module and the multi-stage heat recovery and utilization module. The water condensed in the energy saver is collected in the lower end cover. The condensate is collected by the water level difference. On the other hand, the condensed water itself has a lot of heat, which effectively improves the cooling efficiency of the waste gas. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of a waste heat recovery system for a waste pipe of a flat ironing machine, provided as an embodiment of the present invention.

[0038] Figure 2 This is a schematic diagram of the energy-saving device provided in an embodiment of the present invention.

[0039] Figure 3 This is a schematic diagram of the condensate redistribution module provided in an embodiment of the present invention.

[0040] Figure 4 This is a schematic diagram of the internal structure of the energy saver provided in an embodiment of the present invention.

[0041] Figure 5 This is a schematic diagram of the separation umbrella provided in an embodiment of the present invention.

[0042] Figure 6 This is a schematic diagram of the structure of a multi-stage heat recovery and utilization module provided in an embodiment of the present invention.

[0043] Figure 7 This is a schematic diagram of the heat dispersion and transfer direction in the energy-saving device provided in an embodiment of the present invention.

[0044] 100. Energy saver; 110. Cylindrical shell; 120. Upper end cover; 121. Cooling water inlet pipe; 122. Exhaust steam outlet; 130. Lower end cover; 131. Exhaust steam inlet; 132. Hot water outlet pipe; 133. Condensate drain pipe; 140. Water vapor separation module; 1401. First separation umbrella; 1402. Second separation umbrella; 1403. Vent; 1404. Support rod; 150. Multi-stage heat recovery and utilization module; 1501. Heat exchanger Modules: 1501A, First-stage heat exchange module; 1501B, Second-stage heat exchange module; 1501C, Third-stage heat exchange module; 1501D, Fourth-stage heat exchange module; 1502, Heat exchange medium inlet; 1503, Heat exchange medium outlet; 160, Condensate redistribution module; 1601, Liquid level detection module; 1602, Suction device; 1603, Storage device; 1604, Pumping device; 170, Temperature acquisition module; 200, Control system. Implementation

[0045] All features disclosed in this specification, or all steps in all disclosed methods or processes, may be combined in any way, except for mutually exclusive features and / or steps.

[0046] Any feature disclosed in this specification (including any appended claims, abstract, and drawings) may be replaced by other equivalent or similar features for a similar purpose, unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is merely one example of a series of equivalent or similar features.

[0047] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings and examples.

[0048] This invention provides a waste heat recovery system for the waste pipe of a flat ironing machine. A schematic diagram of the system is shown below. Figure 1 As shown:

[0049] Includes energy-saving device 100 and control system 200;

[0050] The energy-saving device 100 is automatically adjusted by the control system 200, and the waste heat recovery efficiency of the waste pipe of the flat ironing machine is improved through adaptive adjustment control.

[0051] like Figure 2-6As shown, the energy-saving device 100 includes a cylindrical housing 110. An upper end cover 120 and a lower end cover 130 are respectively provided at the upper and lower ends of the cylindrical housing 110. The upper end cover 120 and the lower end cover 130 are sealed to the cylindrical housing 110. A cooling water inlet pipe 121 and an exhaust gas outlet 122 are provided on the upper end cover 120, penetrating through it. An exhaust gas inlet 131, a hot water outlet pipe 132, and a condensate water outlet are provided on the lower end cover 130. Drain pipe 133, exhaust gas inlet 131, hot water outlet pipe 132, and condensate drain pipe 133 pass through the lower end cover 130. Inside the cylindrical shell 110, there is a water vapor separation module 140 and a multi-stage heat recovery module 150. The water vapor separation module 140 is located at one end near the lower end cover 130, and the multi-stage heat recovery module 140 is located at one end near the upper end cover 120. The multi-stage heat recovery module 140 is connected to the cooling water inlet pipe 121 and the hot water outlet pipe 132.

[0052] The waste steam entering the energy-saving device 100 passes through the water vapor separation module 140 and the multi-stage heat recovery and utilization module 150 in sequence. After the water vapor in the waste steam is condensed, it is collected in the lower end cover 130 through the water vapor separation module 140 and discharged through the condensate drain pipe 133. The high-temperature waste steam in the multi-stage heat recovery and utilization module 150 heats the cooling water through gradient amplification heating, realizing the utilization of waste steam heat. The hot water that has absorbed the heat of the waste steam is discharged from the hot water outlet pipe 132 on the lower end cover 130, and the waste steam that has released heat is discharged from the waste steam outlet 122 on the upper end cover 120.

[0053] Temperature acquisition modules 170 are installed on the cooling water inlet pipe 121, the exhaust steam outlet 122, the exhaust steam inlet 131, the hot water outlet pipe 132, and the condensate drain pipe 133.

[0054] The control system 200 is connected to the energy saver 100 and is used to acquire temperature information collected in real time by the temperature acquisition module 170. The temperature information includes the water temperature of the cooling water inlet pipe, the water temperature of the hot water outlet pipe, the water temperature of the condensate drain pipe, the exhaust steam temperature at the exhaust steam outlet, and the exhaust steam temperature at the exhaust steam inlet. The control system 200 controls the energy saver based on the temperature information.

[0055] The control system acquires temperature information from the temperature acquisition module in real time, calculates the heat exchange efficiency of the heat exchange module, and analyzes the temperature information to facilitate adjustments to the energy saver so that it can operate at its optimal state.

[0056] In this system, the waste heat in the exhaust steam from the ironing machine's exhaust pipe is transferred to the energy-saving device 100. This system transfers the high-temperature heat source with a very small cross-section through layers, and then uses this heat energy to gradually heat the water passing through another channel of the same pipe. After being heated step by step, the water temperature can reach nearly 70°C. Therefore, with this system, as long as the ironing machine is turned on, there will be a continuous supply of hot water. This not only utilizes the waste heat discharged by the ironing machine, saving on natural gas costs for heating hot water, but also reduces the temperature of the exhaust pipe, reduces the amount of white smoke emitted during the ironing machine's operation, reduces the urban heat island effect, and reduces the pressure on urban environmental protection.

[0057] The following describes specific embodiments. Figure 1 Each module is explained.

[0058] like Figure 4 As shown, in order to ensure that the condensate collected at the lower end cover 130 can be smoothly discharged through the condensate drain pipe 133, in this embodiment the condensate drain pipe 133 includes a condensate inlet end and a condensate outlet end. The condensate inlet end is the end close to the water vapor separation module, and the condensate inlet end is not higher than the inner side of the lower end cover.

[0059] like Figure 3 As shown, the energy saver also includes a condensate redistribution module 160. The condensate redistribution module 160 includes a liquid level detection module 1601, a suction device 1602, a storage device 1603, and a pumping device 1604. The suction device 1602 is connected to the condensate drain pipe 133. The liquid level detection module 1601 is installed on the lower end cover 130 to detect the liquid level of condensate in the lower end cover 130. The storage device 1603 is used to store condensate. The pumping device 1604 is connected to the storage device 1603.

[0060] The exhaust steam from the ironing machine contains a large amount of water vapor. After the water vapor condenses in the economizer, it is discharged through the condensate drain pipe 133. In order to ensure the smooth discharge of condensate, this embodiment is equipped with a liquid level detection module 1601 on the lower end cover 130. The liquid level of the condensate collected in the lower end cover 130 should not be higher than the end of the exhaust steam inlet 131 near the water vapor separation module 140. If too much condensate accumulates in the lower end cover 130 and flows back into the ironing machine through the exhaust steam inlet 131, it will affect the ironing machine. By setting the liquid level detection module, the amount of condensate in the lower end cover is monitored in real time. If the condensate backflow is obstructed, the condensate can be quickly discharged through the suction device 1602 to ensure the normal operation of the ironing machine.

[0061] On the other hand, the flow rate of condensate collected from the energy saver is relatively small. The condensate can be collected by the storage device 1603 and then pumped to the required parts, such as domestic water or washing machine water, through the pumping device 1604, so as to realize the reuse of condensate.

[0062] To achieve efficient recovery of water vapor from the waste steam in the ironing machine and prevent it from flowing back into the machine through the waste steam inlet 131, this embodiment provides a water vapor separation module, the structure of which is as follows: Figure 4 As shown:

[0063] like Figure 4 and Figure 5 As shown, the water vapor separation module 140 is disposed inside the cylindrical shell 110 and located above the exhaust gas inlet 131. The water vapor separation module 140 consists of a first separation umbrella 1401 and several second separation umbrellas 1402 arranged sequentially along the axial direction of the cylindrical shell 110.

[0064] The top of the first separation umbrella 1401 is close to the multi-stage heat recovery module 150, and no vent 1403 is provided in the center. The size of the first separation umbrella 1401 is smaller than the size of the adjacent second separation umbrella 1402.

[0065] Several second separation umbrellas 1402 are located below the first separation umbrella 1401, and a vent 1403 is provided in the center;

[0066] Along the direction away from the multi-stage heat recovery module 150, the lower circumferential diameter of the second separation umbrella 1402 and the diameter of the vent 1403 gradually increase, and the lower circumferential diameter of the second separation umbrella 1402 near the exhaust gas inlet 131 is larger than the diameter of the exhaust gas inlet 131.

[0067] Through this structure, exhaust gas accumulates on the inner wall of the first separation umbrella 1401 near the multi-stage heat recovery module 150 through the vent 1403, forming condensate. The condensate falls along the inner wall of the first separation umbrella 1401 to the outer wall of the second separation umbrella 1402. The condensate falls step by step along the outer walls of several second separation umbrellas and collects in the lower end cover 130. At the same time, another part of the water vapor carried in the exhaust gas condenses in the multi-stage heat recovery module 150, forming condensate. It falls to the outer wall of the first separation umbrella 1401 near the multi-stage heat recovery module 150, falls step by step, and collects in the lower end cover 130. The condensate collected in the lower end cover 130 is discharged from the condensate drain pipe 133.

[0068] The number of separation umbrellas 1401 can be designed to be multiple depending on the size of the energy saver 100. In this embodiment, for example... Figure 5As shown, the water vapor separation module 140 includes two second separation umbrellas 1402. The first separation umbrella 1401 and the second separation umbrella 1402 are connected by a support rod 1403, and the second separation umbrella 1402 is connected to the lower end cover 130 by the support rod 1403. The second separation umbrella 1402 near the exhaust gas inlet 131 is connected to the lower end cover 130 by the support rod 1403.

[0069] To achieve the recovery and reuse of heat from the exhaust steam of a flat ironing machine, this embodiment provides a multi-stage heat recovery and reuse module, the structure of which is as follows: Figure 6 As shown:

[0070] The multi-stage heat recovery and utilization module 150 is composed of several heat exchange modules 1501, and the heat exchange module 1501 is provided with a heat exchange medium inlet end 1502 and a heat exchange medium outlet end 1503.

[0071] The multi-stage heat recovery and utilization module 150 can be designed as multiple heat exchange modules according to the temperature of the waste gas. Multiple heat exchange modules can be connected in series or in parallel.

[0072] like Figure 6 As shown, in this embodiment, the multi-stage heat recovery and utilization module 150 is composed of four heat exchange modules 1501 connected in series. The four heat exchange modules 1501 are respectively a first-stage heat exchange module 1501A, a second-stage heat exchange module 1501B, a third-stage heat exchange module 1501C, and a fourth-stage heat exchange module 1501D. The heat exchange medium inlet end of the first-stage heat exchange module 1501A is connected to the cooling water inlet pipe 121. The heat exchange medium outlet end of the first-stage heat exchange module 1501A is connected to the heat exchange medium inlet end of the second-stage heat exchange module 1501B. The heat exchange medium outlet end of the second-stage heat exchange module 1501B is connected to the heat exchange medium inlet end of the third-stage heat exchange module 1501C. The heat exchange medium outlet end of the third-stage heat exchange module 1501C is connected to the heat exchange medium inlet end of the fourth-stage heat exchange module 1501D. The heat exchange medium outlet end of the fourth-stage heat exchange module 1501D is connected to the hot water outlet pipe 132.

[0073] The heat exchange tubes arranged within the first-stage heat exchange module 1501A, the second-stage heat exchange module 1501B, the third-stage heat exchange module 1501C, and the fourth-stage heat exchange module 1501D have rectangular outlines of the same size.

[0074] The waste gas near the inlet has high heat content. After passing through a multi-stage heat recovery module, its temperature decreases. To achieve efficient utilization of the waste gas heat, in this embodiment, the number of heat exchange tubes in the first-stage heat exchange module is [number missing]. N The cross-sectional area of ​​the heat exchange tube is s The number of heat exchange tubes in the second-stage heat exchange module is: N / 2, the cross-sectional area of ​​the heat exchange tube is 2 sThe number of heat exchange tubes in the third-stage heat exchange module is: N / 3, the heat exchanger tube cross-sectional area is 3 s The number of heat exchange tubes in the fourth-stage heat exchange module is N / 4, the heat exchanger tube cross-sectional area is 4 s .

[0075] With the above structure, the volume ratio of cooling water passing through the heat exchange tubes per unit length in the first-stage heat exchange module, the second-stage heat exchange module, the third-stage heat exchange module, and the fourth-stage heat exchange module is 1:2:3:4, thus realizing the step-by-step recovery and utilization of heat.

[0076] like Figure 7 As shown, the heat transfer path and direction in the multi-stage heat recovery module are shown. The high-temperature waste heat in the cylindrical shell 110 forms a circular high-temperature area. Through the heat exchange module 1501, the heat diffuses to the surroundings. The high-temperature heat source with a very small cross section is transferred layer by layer. Then, using this heat energy, the water passing through another channel of the tube is gradually heated in a gradient. After being heated step by step, the water temperature can reach nearly 70°C.

[0077] In order to enable the control system to control the energy saver, a controllable valve is installed at the inlet of the cooling water inlet pipe 121 or the heat exchange medium inlet of the first-stage heat exchange module 1501A. The control system adjusts the controllable valve according to the temperature information to regulate the flow rate of the cooling water.

[0078] Multiple heat exchange modules are connected in series, resulting in a simple overall structure and easy maintenance.

[0079] In another embodiment of the present invention, the multi-stage heat recovery and utilization module 150 is composed of four heat exchange modules 1501 connected in parallel. The four heat exchange modules 1501 are respectively a first-stage heat exchange module 1501A, a second-stage heat exchange module 1501B, a third-stage heat exchange module 1501C, and a fourth-stage heat exchange module 1501D. The heat exchange medium inlet ends of the first-stage heat exchange module 1501A, the second-stage heat exchange module 1501B, the third-stage heat exchange module 1501C, and the fourth-stage heat exchange module 1501D are respectively connected to the cooling water inlet pipe 121, and the heat exchange medium outlet ends of the first-stage heat exchange module 1501A, the second-stage heat exchange module 1501B, the third-stage heat exchange module 1501C, and the fourth-stage heat exchange module 1501D are respectively connected to the hot water outlet pipe 132.

[0080] Controllable valves are installed at the inlet ends of the heat exchange medium of the first-stage heat exchange module 1501A, the second-stage heat exchange module 1501B, the third-stage heat exchange module 1501C, and the fourth-stage heat exchange module 1501D, respectively. Alternatively, controllable valves are installed at the outlet ends of the heat exchange medium of the first-stage heat exchange module 1501A, the second-stage heat exchange module 1501B, the third-stage heat exchange module 1501C, and the fourth-stage heat exchange module 1501D, respectively. The control system adjusts the controllable valves according to the temperature information to control the flow rate of cooling water in the first-stage heat exchange module 1501A, the second-stage heat exchange module 1501B, the third-stage heat exchange module 1501C, and the fourth-stage heat exchange module 1501D, respectively.

[0081] Multiple heat exchange modules 1501 are connected in parallel. The controllable valves are set at the inlet or outlet of each heat exchange module to achieve graded control. When one heat exchange module fails, the system can still operate normally by shutting down the heat exchange module and adjusting the heat exchange power of the other heat exchange modules. The parallel mode device structure is relatively complex, but the adjustable range is larger, which can meet the needs of treating waste gas at different temperatures.

[0082] According to another embodiment of the present invention, this embodiment discloses a waste heat recovery method for a waste exhaust pipe of a flat ironing machine, employing a waste heat recovery system for the waste exhaust pipe of a flat ironing machine. The control method includes the following steps:

[0083] Step 1: The exhaust steam from the flat iron's exhaust pipe enters the economizer through the exhaust steam inlet on the lower end cover, and the control system collects the exhaust steam temperature at the exhaust steam inlet.

[0084] Step 2: The control system determines whether to activate the economizer based on the exhaust gas temperature at the exhaust gas inlet.

[0085] When the temperature of the exhaust gas at the inlet is greater than or equal to the preset temperature, the economizer will be turned on. The preset temperature is calculated based on the average temperature of the exhaust gas discharged during the ironing operation of the flat iron.

[0086] If the exhaust gas inlet temperature is less than the preset temperature, return to step 1;

[0087] Step 3: Temperature Information Acquisition

[0088] Collect the water temperature in the cooling water inlet pipe;

[0089] The waste gas entering the energy saver passes through the water vapor separation module and the multi-stage heat recovery and utilization module in sequence. The water vapor in the waste gas is condensed and collected in the lower end cover through the water vapor separation module, and then discharged through the condensate drain pipe. The water temperature of the condensate drain pipe is collected.

[0090] The exhaust gas enters the economizer through the exhaust gas inlet, and the temperature of the exhaust gas at the exhaust gas inlet is collected.

[0091] The high-temperature waste gas, after passing through the multi-stage heat recovery and utilization module, heats the cooling water through gradient amplification heating, thereby realizing the utilization of waste gas heat. The hot water that has absorbed the heat of the waste gas is discharged from the hot water outlet pipe on the lower end cover, and the water temperature of the hot water outlet pipe is collected.

[0092] The exhaust gas that has released heat is discharged from the exhaust gas outlet on the upper end cover, and the exhaust gas temperature at the exhaust gas outlet is collected.

[0093] Step 4: The control system adjusts the energy saver based on the temperature information collected in Step 3 to ensure that the hot water outlet temperature reaches 55℃-70℃.

[0094] This method uses an automated energy-saving device controlled and regulated based on temperature information to transfer concentrated waste heat. The high-temperature heat source with a very small cross-section is transferred layer by layer, and then this heat energy is used to gradually heat the water passing through another channel of the same tube. After step-by-step heating, the water temperature can reach nearly 70°C. The water vapor separation module and the multi-stage heat recovery and utilization module realize the separation of water and gas in the waste vapor. The water condensed in the energy-saving device is collected in the lower end cover. The condensate is collected by the water level difference. The temperature of the condensate is 35-45°C.

[0095] The above descriptions are merely preferred examples of the invention and are not intended to limit the invention. Although the invention has been described in detail with reference to the foregoing examples, those skilled in the art can still modify the technical solutions described in the foregoing examples or make equivalent substitutions for some of the technical features. All modifications and equivalent substitutions made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A waste heat recovery system for the waste discharge pipe of a flat ironing machine, characterized in that, This includes energy-saving devices and control systems; The energy-saving device includes a cylindrical shell with an upper end cover and a lower end cover at its upper and lower ends, respectively. The upper and lower end covers are sealed to the cylindrical shell. A cooling water inlet pipe and an exhaust gas outlet are provided on the upper end cover, which penetrate through the upper end cover. An exhaust gas inlet pipe, a hot water outlet pipe, and a condensate drain pipe are provided on the lower end cover, which penetrate through the lower end cover. A water vapor separation module and a multi-stage heat recovery and utilization module are provided inside the cylindrical shell. The water vapor separation module is housed inside a cylindrical shell and located above the exhaust gas inlet. The water vapor separation module consists of a first separation umbrella and several second separation umbrellas arranged sequentially along the axial direction of the cylindrical shell. The top of the first separation umbrella is close to the multi-stage heat recovery module, and there is no vent in the center. The size of the first separation umbrella is smaller than the size of the adjacent second separation umbrella. Several second separation umbrellas are located below the first separation umbrella, with a vent in the center; Along the direction away from the multi-stage heat recovery module, the lower circumferential diameter and the vent diameter of the second separation umbrella gradually increase, and the lower circumferential diameter of the second separation umbrella closer to the exhaust gas inlet is larger than the diameter of the exhaust gas inlet. The multi-stage heat recovery module is located at one end near the upper end cover and is connected to the cooling water inlet pipe and the hot water outlet pipe. The multi-stage heat recovery and utilization module is composed of four heat exchange modules connected in series. Each heat exchange module is provided with a heat exchange medium inlet and a heat exchange medium outlet. The four heat exchange modules are respectively the first-stage heat exchange module, the second-stage heat exchange module, the third-stage heat exchange module, and the fourth-stage heat exchange module. The heat exchange medium inlet of the first-stage heat exchange module is connected to the cooling water inlet pipe; the heat exchange medium outlet of the first-stage heat exchange module is connected to the heat exchange medium inlet of the second-stage heat exchange module; the heat exchange medium outlet of the second-stage heat exchange module is connected to the heat exchange medium inlet of the third-stage heat exchange module; the heat exchange medium outlet of the third-stage heat exchange module is connected to the heat exchange medium inlet of the fourth-stage heat exchange module; and the heat exchange medium outlet of the fourth-stage heat exchange module is connected to the hot water outlet pipe. A controllable valve is installed at the inlet of the cooling water inlet pipe or the heat exchange medium inlet of the first-stage heat exchange module. The control system adjusts the controllable valve according to the temperature information to regulate the flow rate of the cooling water. Temperature acquisition modules are installed on the cooling water inlet pipe, exhaust steam outlet, exhaust steam inlet, hot water outlet pipe, and condensate drain pipe. The control system is connected to the energy saver and is used to acquire temperature information collected in real time by the temperature acquisition module. The temperature information includes the water temperature of the cooling water inlet pipe, the water temperature of the hot water outlet pipe, the water temperature of the condensate drain pipe, the exhaust steam temperature at the exhaust steam outlet, and the exhaust steam temperature at the exhaust steam inlet. The control system controls the energy saver based on the temperature information.

2. The waste heat recovery system for the waste pipe of a flat ironing machine according to claim 1, characterized in that, The condensate drain pipe includes a condensate inlet end and a condensate outlet end. The condensate inlet end is the end closest to the water vapor separation module, and the condensate inlet end is not higher than the inner side of the lower end cover.

3. A waste heat recovery system for a waste pipe of a flat ironing machine according to claim 2, characterized in that, The energy-saving device also includes a condensate redistribution module, which includes a liquid level detection module, a suction device, a storage device, and a pumping device. The suction device is connected to the condensate drain pipe. The liquid level detection module is installed on the lower end cover to detect the liquid level of the condensate inside the lower end cover. The storage device is used to store condensate, and the pumping device is connected to the storage device.

4. A waste heat recovery system for a waste pipe of a flat ironing machine according to claim 1, characterized in that, The water vapor separation module includes two second separation umbrellas. The first separation umbrella and the second separation umbrella are connected by support rods. The second separation umbrella near the exhaust gas inlet is connected to the lower end cover by support rods.

5. A waste heat recovery system for a waste pipe of a flat ironing machine according to claim 1, characterized in that, The heat exchange tubes arranged in the first-stage heat exchange module, the second-stage heat exchange module, the third-stage heat exchange module, and the fourth-stage heat exchange module have the same rectangular outer contour.

6. A waste heat recovery system for a waste pipe of a flat ironing machine according to claim 5, characterized in that, The number of heat exchange tubes in the first-stage heat exchange module is N The cross-sectional area of ​​the heat exchange tube is s The number of heat exchange tubes in the second-stage heat exchange module is: N / 2, the cross-sectional area of ​​the heat exchange tube is 2 s The number of heat exchange tubes in the third-stage heat exchange module is: N / 3, the heat exchanger tube cross-sectional area is 3 s The number of heat exchange tubes in the fourth-stage heat exchange module is N / 4, the heat exchanger tube cross-sectional area is 4 s .

7. A method for waste heat recovery in the waste discharge pipe of a flat ironing machine, employing any one of the waste heat recovery systems for waste discharge pipes of a flat ironing machine as described in claims 1-6, comprising the following steps: Step 1: The exhaust steam from the flat iron's exhaust pipe enters the economizer through the exhaust steam inlet on the lower end cover, and the control system collects the exhaust steam temperature at the exhaust steam inlet. Step 2: The control system determines whether to activate the economizer based on the exhaust gas inlet temperature. When the temperature of the exhaust gas at the inlet is greater than or equal to the preset temperature, the economizer will be turned on. The preset temperature is calculated based on the average temperature of the exhaust gas discharged during the ironing operation of the flat iron. If the exhaust gas inlet temperature is less than the preset temperature, return to step 1; Step 3: Temperature Information Acquisition Collect the water temperature in the cooling water inlet pipe; The waste gas entering the energy saver passes through the water vapor separation module and the multi-stage heat recovery and utilization module in sequence. The water vapor in the waste gas is condensed and collected in the lower end cover through the water vapor separation module, and discharged through the condensate drain pipe. The water temperature of the condensate drain pipe is collected. The exhaust gas enters the economizer through the exhaust gas inlet, and the temperature of the exhaust gas at the exhaust gas inlet is collected. The exhaust gas passes through a multi-stage heat recovery and utilization module. The high-temperature exhaust gas heats the cooling water through a gradient amplification heating method, thereby realizing the utilization of the exhaust gas heat. The hot water that has absorbed the heat of the exhaust gas is discharged from the hot water outlet pipe on the lower end cover, and the water temperature of the hot water outlet pipe is collected. The exhaust gas that has released heat is discharged from the exhaust gas outlet on the upper end cover, and the exhaust gas temperature at the exhaust gas outlet is collected. Step 4: The control system adjusts the energy saver based on the temperature information collected in Step 3 to ensure that the hot water outlet temperature reaches 55℃-70℃.

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