Device and method for recycling dry residual heat

Abstract

The application provides a device for recycling drying waste heat, comprising a drying mold heated by steam, an air collecting tank, and a steam heat pump; the air outlet of the air collecting tank is connected with the air inlet of the drying mold; the first air inlet of the steam heat pump is connected with the air outlet of the drying mold to receive secondary steam discharged from the drying mold; the second air inlet of the steam heat pump is used to receive high-pressure steam to compress and heat the secondary steam; the air outlet of the steam heat pump is connected with the air inlet of the air collecting tank to pass the heated steam into the air collecting tank; and the air collecting tank is configured to supply the heated steam to the drying mold. The application also provides a method for recycling drying waste heat, which is performed by the above device. The device and the method of the application realize recycling of drying waste heat, energy saving and emission reduction, good continuity, and reduction of production cost.

Description

Technical Field

[0001] This application belongs to the field of papermaking equipment technology, and in particular relates to an apparatus and a method for reusing waste heat from drying. Background Technology

[0002] Pulp molding is a three-dimensional papermaking technology. It uses waste paper as raw material, shaping it into specific paper products using special molds on a molding machine. It has four main advantages: First, the raw material is waste paper, including cardboard, waste corrugated cardboard, and waste paper scraps, making it widely available. Second, the production process involves pulping, adsorption molding, drying, and setting, making it environmentally friendly. Third, it is recyclable and reusable. Fourth, it is smaller than foamed plastics, can be stacked, and is convenient for transportation. Besides being used for lunch boxes and tableware, pulp molding is increasingly used for industrial cushioning packaging, and its development is very rapid.

[0003] Currently, pulp molding products are generally shaped and dried inside the mold. Due to the discontinuity of this drying process and the large amount of air mixed in with the secondary steam, it is difficult to directly recover and utilize the waste heat from drying. This not only causes energy waste and high production costs, but also results in a poor working environment. Summary of the Invention

[0004] In view of one or more deficiencies in the prior art, the present invention provides an apparatus for reusing waste heat from drying, comprising:

[0005] The drying mold is heated by steam and has an air inlet and an air outlet.

[0006] A gas collecting tank, the outlet of which is connected to the inlet of the drying mold; and

[0007] A steam heat pump is provided, wherein the first air inlet of the steam heat pump is connected to the air outlet of the drying mold to receive secondary steam discharged from the drying mold, the second air inlet of the steam heat pump is used to receive high-pressure steam, the high-pressure steam compresses and heats the secondary steam, the air outlet of the steam heat pump is connected to the air inlet of the gas collecting tank to introduce the heated steam into the gas collecting tank, and the gas collecting tank is configured to supply heated steam to the drying mold.

[0008] According to one aspect of the invention, it further includes:

[0009] A vacuum tank having a condenser, wherein the air inlet of the vacuum tank is connected to the air outlet of the drying mold;

[0010] A vacuum pump is connected to the outlet of the vacuum tank.

[0011] According to one aspect of the invention, it further includes:

[0012] A steam-water separator has a liquid inlet, which is connected to the liquid outlet of the drying mold; the first air outlet of the steam-water separator is connected to the first air inlet of the steam heat pump.

[0013] According to one aspect of the invention, it further includes:

[0014] An exhaust valve has a first end and a second end opposite to the first end; wherein the first end of the exhaust valve is connected to the air inlet of the vacuum tank; and the second end of the exhaust valve is connected to the secondary steam outlet of the drying mold.

[0015] According to one aspect of the invention, it further includes:

[0016] A gas collecting valve has a first end and a second end opposite to the first end; wherein the first end of the gas collecting valve is connected to the first air inlet of the steam heat pump via a pre-valve; and the second end of the gas collecting valve is connected to the secondary steam outlet of the drying mold.

[0017] According to one aspect of the invention, it further includes:

[0018] An air inlet valve has a first end and a second end opposite to the first end; wherein the first end of the air inlet valve is connected to the air outlet of the air collection tank; and the second end of the air inlet valve is connected to the air inlet of the drying mold.

[0019] According to one aspect of the invention, it further includes:

[0020] An air vent valve has a first end and a second end opposite to the first end; wherein the first end of the air vent valve is connected to the air inlet of the vacuum tank; and the second end of the air vent valve is connected to the second air outlet of the gas-water separator.

[0021] According to one aspect of the invention, it further includes:

[0022] A return gas valve has a first end and a second end opposite to the first end; wherein the first end of the return gas valve is connected to the first end of the gas collecting valve; and the second end of the return gas valve is connected to the first gas outlet of the gas-water separator.

[0023] According to one aspect of the invention, the drying mold comprises:

[0024] The heating chamber includes a first port and a second port opposite to the first port; the first port of the heating chamber is connected to the second end of the air inlet valve to receive the steam; the second port of the heating chamber is connected to the first end of the drain valve to discharge the steam.

[0025] The mold cavity is formed in the drying mold, and the shape of the mold cavity corresponds to the shape of the heating chamber; the mold cavity also includes an outlet for secondary steam discharge.

[0026] According to one aspect of the invention, the cavity temperature of the drying mold is not lower than a first preset temperature.

[0027] According to one aspect of the invention, the pressure of the vacuum tank is less than a preset pressure.

[0028] According to one aspect of the present invention, the pressure fluctuation range of the gas collecting tank is less than ±20%; the pressure of the gas stored in the gas collecting tank is not less than a preset pressure, and the temperature is not lower than a second preset temperature.

[0029] The present invention also provides a method for reusing waste heat from drying, comprising:

[0030] S201: Adjust the air inlet valve to bring the temperature in the drying mold to the preset temperature, and transfer the dehydrated material into the drying mold;

[0031] S202: Open the exhaust valve and vacuum the drying mold for a preset time; and

[0032] S203: Close the exhaust valve, open the gas collecting valve, and the steam heat pump compresses and heats the secondary steam evaporated from the material for further heating of the material;

[0033] The method is performed by the aforementioned apparatus.

[0034] The apparatus and method of the present invention can utilize the secondary steam in the mold cavity and the high-temperature steam in the heating chamber to dry the pulp molded blank, which has good continuity, is conducive to energy conservation and emission reduction, and thus reduces production costs. Attached Figure Description

[0035] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0036] Figure 1 A schematic diagram of an apparatus for reusing waste heat from drying according to an embodiment of the present invention is shown; and

[0037] Figure 2 A schematic diagram of a method for reusing waste heat from drying according to an embodiment of the present invention is shown. Detailed Implementation

[0038] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0039] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0040] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0041] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0042] The following disclosure provides many different embodiments or examples for implementing various structures of the invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0043] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0044] Figure 1 A schematic diagram of an apparatus 100 for reusing waste heat from drying, according to an embodiment of the present invention, is shown below. Figure 1 The device 100 will be described in detail.

[0045] like Figure 1 As shown, the device 100 includes a drying mold 1, a steam heat pump 2, and a gas collecting tank 3. The drying mold 1 has a mold cavity 12 for placing the pulp molding preform to be dried (e.g., ...). Figure 1 (As shown by the cross-shaded lines in the diagram), the steam heat pump 2 and the gas collection tank 3 are connected in sequence to the drying mold 1 to supply high-temperature steam to the drying mold 1 to dry the pulp molded preform.

[0046] Continue to refer to Figure 1 The drying mold 1 includes a heating chamber 11 and a mold cavity 12. The heating chamber 11 is used to introduce high-temperature steam, which heats the surrounding mold portions. Preferably, the heating chamber 11 is located close to the mold cavity 12, thereby improving heat conduction efficiency and facilitating the heating of the pulp preform located in the mold cavity 12 by the high-temperature steam. Figure 1 As shown, the heating chamber 11 includes a first port 111 and a second port 112 opposite to the first port 111. The first port 111 of the heating chamber 11 is exposed to the surface of the drying mold 1 and is used to introduce high-temperature steam. During the flow in the heating chamber 11, the temperature of the high-temperature steam decreases and may partially condense into droplets. The remaining steam and droplets are discharged through the second port 112 of the heating chamber 11. Therefore, the high-temperature steam enters from the first port 111 and exits from the second port 112, heating the pulp molding preform in the adjacent mold cavity 12 in the process. Preferably, the heating chamber 11 is designed with a certain degree of curvature to increase the residence time of the high-temperature steam and enhance the heating effect.

[0047] The mold cavity 12 is formed in the drying mold 1 and is used to hold the pulp molding preform to be dried after extrusion and dewatering. The shape of the mold cavity 12 can be designed to correspond to the pulp molding preform. The mold cavity 12 has an air outlet 121 ( Figure 1 (Illustrated schematically using lines). The vent 121 connects to the outside of the drying mold 1, so that when the pulp molded blank in the mold cavity 12 is heated, the steam generated from the pulp molded blank can be discharged to the outside of the drying mold 1 through the vent 121. The present invention does not limit the specific location of the vent 121 on the mold cavity 12. Preferably, the vent 121 is located in the upper middle position of the mold cavity 12 to allow gas discharge, the gas including steam (also referred to as "secondary steam") and air. During the process of high-temperature steam passing through the heating chamber 11, the temperature of the high-temperature steam will drop due to heat exchange, and some condensate will be generated. The steam and condensate are discharged from the second port 112. After the pulp molded blank is heated, the moisture in it evaporates, generating secondary steam, which is discharged from the vent 121 of the mold cavity 12 of the drying mold 1.

[0048] The shape of the mold cavity 12 preferably corresponds to the shape of the heating cavity 11. Optionally, the shapes of the heating cavity 11 and the mold cavity 12 are, for example, "V-shaped", "W-shaped", "U-shaped", "trapezoidal", etc. Furthermore, the present invention does not limit the specific number of heating cavities 11; that is, the drying mold 1 may have one or more heating cavities 11 to heat the pulp molding blank in the mold cavity 12. It should be understood that this embodiment is merely illustrative and does not constitute a limitation of the present invention.

[0049] According to a preferred embodiment of the present invention, reference continues... Figure 1 The drying mold 1 has two heating chambers 11, located above and below the mold cavity 12, respectively, to fully heat the extruded and dehydrated pulp preform to be dried in the mold cavity 12. Preferably, the temperature of the mold cavity 12 in the drying mold 1 is not lower than 120°C.

[0050] According to a preferred embodiment of the present invention, reference continues... Figure 1The steam heat pump 2, for example, is a steam jet heat pump, having a first inlet 21, a second inlet 22, and an outlet 23. The first inlet 21 is located to the side of the steam heat pump 2 and is connected to the outlet 121 of the mold cavity 12 of the drying mold 1 to receive secondary steam discharged from the outlet 121 of the mold cavity 12 of the drying mold 1. The second inlet 22 of the steam heat pump 2 is located at the main position of the steam heat pump 2 and is used to receive high-pressure steam as the main driving steam. This high-pressure steam provides compression power to the secondary steam in the steam heat pump 2, compressing and heating it. In this way, the secondary steam discharged from the outlet 121 of the mold cavity 12 of the drying mold 1 can be reused, compressed and heated, and then reintroduced into the heating chamber 11 of the drying mold 1 for heating purposes.

[0051] According to a preferred embodiment of the present invention, reference continues... Figure 1 The gas collecting tank 3 is connected between the steam heat pump 2 and the drying mold 1. The gas collecting tank 3 has an inlet 31 and an outlet 32. The inlet 31 of the gas collecting tank 3 is connected to the outlet 23 of the steam heat pump 2 to allow heated steam to be introduced into the gas collecting tank 3. The gas collecting tank 3 is configured to supply heated steam to the drying mold 1. The steam heat pump 2 can maintain the gas pressure stored in the gas collecting tank 3 at no less than 0.6 MPa and the temperature at no less than 160°C. It should be understood that this embodiment is merely illustrative and does not constitute a limitation of the present invention.

[0052] According to a preferred embodiment of the present invention, reference continues... Figure 1 The device further includes a vacuum tank 4 and a vacuum pump 5. The vacuum tank 4 has an air inlet 41, an air outlet 42, and a condenser 43. The air inlet 41 of the vacuum tank 4 is connected to the air outlet 121 of the mold cavity 12 of the drying mold 1, and the vacuum pump 5 is connected to the air outlet 42 of the vacuum tank 4. The gauge pressure of the vacuum tank 4 is preferably less than -0.06 MPa. The vacuum tank 4 and the vacuum pump 5 are used to evacuate the mold cavity 12 before drying, reducing the air content in the mold cavity 12, so that the steam generated by the pulp preform in the mold cavity 12 can be discharged more quickly when heated subsequently.

[0053] The device 100 can be equipped with one or more valves at various locations as needed, as described below. Figure 1 Detailed description.

[0054] According to a preferred embodiment of the present invention, reference continues... Figure 1The device further includes an exhaust valve 6, which has a first end 61 and a second end 62 opposite to the first end; wherein the first end 61 of the exhaust valve 6 is connected to the air inlet 41 of the vacuum tank 4; and the second end 62 of the exhaust valve 6 is connected to the secondary steam outlet 121 of the mold cavity 12 of the drying mold 1. When the temperature in the mold cavity 12 is not lower than a preset temperature, for example 120°C... o At step C, after the extruded and dehydrated pulp preform is transferred to the cavity 12 of the sealed drying mold 1, the exhaust valve 6 is opened, and the vacuum pump 5 evacuates the cavity 12 of the drying mold 1 for a duration of, for example, 1 to 10 seconds. The extracted gas flows into the vacuum tank 4 through a pipe, and is condensed into water by the condenser 43 and discharged.

[0055] According to a preferred embodiment of the present invention, reference continues... Figure 1 The device further includes a gas collecting valve 7 and a pre-valve 8, which are sequentially connected between the secondary steam outlet 121 of the mold cavity 12 of the drying mold 1 and the first air inlet 21 of the steam heat pump 2. The gas collecting valve 7 has a first end 71 and a second end 72 opposite to the first end 71; wherein the first end 71 of the gas collecting valve 7 is connected to the first air inlet 21 of the steam heat pump 2 through the pre-valve 8; the second end 72 of the gas collecting valve 7 is connected to the secondary steam outlet 121 of the mold cavity 12 of the drying mold 1. After the mold cavity 12 of the drying mold 1 is evacuated, the exhaust valve 6 is closed and the gas collecting valve 7 is opened, so that the secondary steam evaporated in the pulp molded wet blank is transported to the steam heat pump 2 through the pipeline and the first air inlet 21 of the steam heat pump 2. After being compressed and heated in the steam heat pump 2, it is introduced back into the heating chamber 11 of the drying mold 1.

[0056] According to a preferred embodiment of the present invention, reference continues... Figure 1 The device further includes an air inlet valve 9, connected between the gas collecting tank 3 and the air inlet 111 of the drying mold 1. The air inlet valve 9 has a first end 91 and a second end 92 opposite to the first end 91; wherein the first end 91 of the air inlet valve 9 is connected to the air outlet 32 ​​of the gas collecting tank 3; and the second end 92 of the air inlet valve 9 is connected to the air inlet 111 of the drying mold 1. By adjusting the air inlet valve 9, the amount of high-temperature steam entering the heating chamber 11 can be dynamically controlled, thereby maintaining the temperature conditions of the mold cavity 12 in the drying mold 1, for example, controlling it to be no lower than a preset temperature.

[0057] According to a preferred embodiment of the present invention, by adjusting the air inlet valve 9, the temperature of the mold cavity 12 in the drying mold 1 can be maintained at no less than 120°C, so as to heat and dry the pulp molded blank in the mold cavity 12.

[0058] According to a preferred embodiment of the present invention, the high-pressure steam main driving steam fed from the second air inlet 22 of the steam heat pump 2 provides compression power to the secondary steam in the steam heat pump 2, compresses and heats the secondary steam in the steam heat pump 2, and after compression and heating, it is introduced into the gas collecting tank 3. The air inlet valve 9 is opened, and the high-temperature steam in the gas collecting tank 3 is transported to the drying mold 1 through the pipeline and the air inlet 111 of the drying mold 1 for further heating of the drying mold 1.

[0059] According to a preferred embodiment of the present invention, the secondary steam discharged from the mold cavity 12 of the drying mold 1 is introduced into the first air inlet 21 of the steam heat pump 2 by adjusting the gas collecting valve 7 for recycling.

[0060] According to a preferred embodiment of the present invention, the device further includes a steam-water separator 10, which has a first exhaust port 101, a second exhaust port 102, a liquid inlet 103, and a gas outlet 104. The liquid inlet 103 of the steam-water separator 10 is connected to the second port 112 of the drying mold 1 via a drain valve 13, thereby receiving steam along with condensate from the second port 112. The height of the first exhaust port 101 is higher than the height of the gas outlet 104. The first exhaust port 101 (via the pre-valve 8) is connected to the first air inlet 21 of the steam heat pump 2. The first exhaust port 101 serves as the main exhaust port, and the exhaust gas is flash steam (secondary steam). The gas outlet 104 serves as an auxiliary exhaust port, and the exhaust gas is a condensable gas such as water vapor (utilizing the height difference). Preferably, the first exhaust port 101 and the gas outlet 104 exhaust alternately, and the opening time and frequency are determined by experience or demand based on the gas content of the raw material. The condensable gases are mainly water vapor and other components from the evaporation of raw material additives.

[0061] According to a preferred embodiment of the present invention, the device further includes a vent valve 14 located at the top cover of the gas-water separator 10. The vent valve 14 has a first end 141 and a second end 142 opposite to the first end 141; wherein the first end 141 of the vent valve 14 is connected to the air inlet 41 of the vacuum tank 4 and to the exhaust valve 6; the second end 142 of the vent valve 14 is connected to the second air outlet 102 of the gas-water separator 10. With this connection, the gas-water separator 10 can be evacuated by the vacuum pump 5 and the vacuum tank 4 to remove air from the gas-water separator 10. For example, the gas-water separator 10 can be evacuated by the vacuum pump 5 and the vacuum tank 4 before heating the pulp molding preform.

[0062] According to a preferred embodiment of the present invention, the device further includes a return gas valve 15, wherein the first gas outlet 101 of the steam-water separator 10 is connected to the pre-valve 8 via the return gas valve 15, and further connected to the first gas inlet 21 of the steam heat pump 2. The return gas valve 15 has a first end 151 and a second end 152 opposite to the first end 151; wherein the first end 151 of the return gas valve 15 is connected to the first end 71 of the gas collecting valve 7; and the second end 152 of the return gas valve 15 is connected to the first gas outlet 101 of the steam-water separator 10.

[0063] According to a preferred embodiment of the present invention, periodically opening the vent valve 14 while simultaneously closing the return valve 15 can remove condensable gases from the steam-water separator 10, thereby improving the heat transfer efficiency of the recycled secondary steam.

[0064] Figure 1 In the illustrated embodiment, the device 100 includes a drying mold 1. According to a preferred embodiment of the invention, the device 100 may also include multiple drying molds 1, each having a certain number and shape of heating chambers 11 and mold cavities 12. The invention does not limit the number of drying molds 1, nor the number and shape of heating chambers 11 and mold cavities 12; users can set them according to actual needs. Multiple drying molds 1 working in coordination can maintain the gas pressure fluctuation in the gas collecting tank 3 at less than ±20%, and can also improve working efficiency.

[0065] The present invention also provides a method for reusing waste heat from drying. Figure 2 A schematic diagram of a method for reusing waste heat from drying according to an embodiment of the present invention is shown. The method 200 is performed by the aforementioned apparatus 100 for reusing waste heat from drying, and the method 200 will be described below.

[0066] In step S201, the air inlet valve 9 is adjusted to bring the temperature in the drying mold 1 to the preset temperature, and the dehydrated material is transferred to the drying mold 1.

[0067] According to a preferred embodiment of the present invention, reference is made to Figure 1 and Figure 2 Adjust the air inlet valve 9 to maintain the temperature in the cavity 12 of the drying mold 1 at no less than 120°C, and transfer the extruded and dehydrated pulp preform to the cavity 12 of the drying mold 1 with the mold cavity sealed.

[0068] In step S202, the exhaust valve 6 is opened, and the drying mold is evacuated for a preset time.

[0069] According to a preferred embodiment of the present invention, the exhaust valve 6 is opened to evacuate the cavity 12 of the drying mold 1 for 1 to 10 seconds, and the vent valve 14 is opened to evacuate the steam-water separator 10 for 1 to 10 seconds.

[0070] In step S203, the exhaust valve is closed and the gas collecting valve is opened. The steam heat pump compresses and heats the secondary steam evaporated from the material, which is then used to heat the material.

[0071] According to a preferred embodiment of the present invention, the exhaust valve 6 is closed and the gas collecting valve 7 is opened. The secondary steam evaporated in the pulp molded blank is compressed and heated by the steam heat pump 2 and then introduced into the gas collecting tank 3 for further heating of the pulp molded blank in the mold cavity 12 of the drying mold 1. The condensate discharged from the drying mold 1 enters the steam-water separator 10 through the drain valve 13.

[0072] After the pulp molded preform has dried to the appropriate moisture content, close the air collection valve 7, open the drying mold 1, and take out the dried pulp molded preform.

[0073] The apparatus and method of the present invention can utilize the secondary steam in the mold cavity and the waste heat air in the heating chamber to dry the pulp molded blank, which has good continuity, is conducive to energy conservation and emission reduction, and thus reduces production costs.

[0074] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An apparatus for reusing waste heat from drying, comprising: The drying mold is heated by steam and has an air inlet and an air outlet. A gas collecting tank, wherein the outlet of the gas collecting tank is connected to the inlet of the drying mold; A steam heat pump is provided, wherein the first air inlet of the steam heat pump is connected to the air outlet of the drying mold to receive secondary steam discharged from the drying mold, the second air inlet of the steam heat pump is used to receive high-pressure steam, the high-pressure steam compresses and heats the secondary steam, and the air outlet of the steam heat pump is connected to the air inlet of the gas collecting tank to introduce the heated steam into the gas collecting tank, and the gas collecting tank is configured to supply heated steam to the drying mold. and An air inlet valve, wherein the first end of the air inlet valve is connected to the air outlet of the air collection tank; and the second end of the air inlet valve is connected to the air inlet of the drying mold. The drying mold includes a heating chamber, the first port of which is connected to the second end of the air inlet valve to receive the steam; the heating chamber is curved.

2. The apparatus according to claim 1, further comprising: A vacuum tank having a condenser, wherein the air inlet of the vacuum tank is connected to the air outlet of the drying mold; A vacuum pump is connected to the outlet of the vacuum tank.

3. The apparatus according to claim 2, further comprising: A vapor-water separator has a liquid inlet, which is connected to the liquid outlet of the drying mold. The first outlet of the steam-water separator is connected to the first inlet of the steam heat pump.

4. The apparatus according to claim 3, further comprising: An exhaust valve has a first end and a second end opposite to the first end; wherein the first end of the exhaust valve is connected to the air inlet of the vacuum tank; and the second end of the exhaust valve is connected to the secondary steam outlet of the drying mold.

5. The apparatus according to claim 4, further comprising: A gas collecting valve has a first end and a second end opposite to the first end; wherein the first end of the gas collecting valve is connected to the first air inlet of the steam heat pump via a pre-valve; and the second end of the gas collecting valve is connected to the secondary steam outlet of the drying mold.

6. The apparatus according to claim 3, further comprising: An air vent valve has a first end and a second end opposite to the first end; wherein the first end of the air vent valve is connected to the air inlet of the vacuum tank; and the second end of the air vent valve is connected to the second air outlet of the gas-water separator.

7. The apparatus according to claim 5, further comprising: A return valve has a first end and a second end opposite to the first end; wherein the first end of the return valve is connected to the first end of the gas collecting valve; and the second end of the return valve is connected to the first gas outlet of the gas-water separator.

8. The apparatus according to any one of claims 1-7, The heating chamber includes a second port opposite to the first port; the second port of the heating chamber is connected to the first end of a drain valve to discharge the steam. The drying mold further includes: The mold cavity is formed in the drying mold, the shape of the mold cavity corresponds to the shape of the heating chamber, and the mold cavity also includes an outlet for secondary steam discharge.

9. The apparatus according to claim 8, wherein the temperature of the drying mold cavity is not lower than a first preset temperature.

10. The apparatus according to any one of claims 2-7, wherein the pressure of the vacuum tank is less than a preset pressure.

11. The apparatus according to any one of claims 1-7, wherein the pressure fluctuation of the gas collecting tank is less than ±20%; the pressure of the gas stored in the gas collecting tank is not less than a preset pressure, and the temperature is not lower than a second preset temperature.

12. A method for reusing waste heat from drying, comprising: S201: Adjust the air inlet valve to bring the temperature in the drying mold to the preset temperature, and transfer the dehydrated material into the drying mold; S202: Open the exhaust valve and vacuum the drying mold for a preset time; and S203: Close the exhaust valve, open the gas collecting valve, and the steam heat pump compresses and heats the secondary steam evaporated from the material for further heating of the material; The method is performed by the apparatus of claim 5.

Images