Canvas dehydration system

Abstract

The present invention provides a canvas dehydration processing system, including a dehydration drying box, wherein the dehydration drying box is provided with a canvas inlet and a canvas outlet, wherein the canvas enters the dehydration drying box through the canvas inlet and is transmitted in the direction of the canvas outlet; in the dehydration drying box, a first dehydration unit, a second dehydration unit, and a third dehydration unit are sequentially arranged in the opposite direction of the canvas transmission direction, wherein the first dehydration unit is connected to an air inlet pipe, the first dehydration unit is connected to the second dehydration unit, the second dehydration unit is connected to the third dehydration unit in sequence, and the third dehydration unit is connected to an air outlet pipe; a heating device is respectively arranged in the first dehydration unit, the second dehydration unit, and the third dehydration unit. The canvas dehydration processing system of the present invention dries the canvas on one side of the dehydration drying box outlet by dry air, displaces the water vapor inside the fabric fiber of the canvas, and makes the high-temperature gas inside the fabric fiber of the canvas contain no moisture.

Description

Technical Field

[0001] The invention relates to the technical field of drying equipment, and in particular to a system for continuously dehydrating canvas using high-temperature steam. Background Art

[0002] After the canvas is initially manufactured and formed, it still contains a certain amount of moisture, so the canvas needs to be dehydrated (that is, dried) to separate the moisture in the canvas and keep the canvas dry. This is not only beneficial to the preservation of the canvas, but also allows the canvas to maintain a good water absorption state, allowing painters and art lovers to have a better painting experience during the painting process.

[0003] At present, the technical solution adopted by the equipment for dehydrating canvas is to directly heat steam and rush the steam into a closed or semi-closed environment. The steam temperature and humidity in the whole environment are almost the same, so the dehydration effect of the canvas cannot reach the best. The reason is that when the canvas is about to leave the dehydration environment, the high temperature of the steam dries the canvas, and the high temperature steam also remains in the fabric fibers of the canvas. The water content in these steams is actually relatively high. After the canvas leaves the dehydration environment and comes into contact with the air; the air temperature at this time is obviously much lower than the temperature of the high temperature steam in the fabric fibers of the canvas, so that the steam in the fabric fibers of the canvas condenses to form small water droplets. Since the fabric fibers of the canvas are relatively dense and the gaps are small, these small water droplets are easy to stay in the fabric fibers of the canvas, and it is difficult to leave, so it is easy to stay for a long time.

[0004] The patent publication number is CN117073356A, which discloses an energy-saving drying system for flushable non-woven fabrics. Its technical solution adopts multiple drying units (to be exact, three, namely the first drying unit, the second drying unit and the third drying unit). The multiple drying units are connected to a common steam inlet pipe, and then after drying, they are connected to the same steam-water separator. In other words, although the reference document adopts a multi-stage drying unit structure design, its technical principle is still the same as the existing steam drying technology. That is: the same steam pipeline supplies steam to different drying units, so the steam water content in each drying unit is the same. Then, in the actual use of such a device, it is inevitable that there will be the problem of steam residue explained by the applicant.

[0005] The applicant found that using external steam to dry the canvas not only wastes energy (the steam source requires a steam generator), but also due to the dense structural characteristics of the canvas fabric fibers, steam residue occurs, which not only fails to save energy but also leads to poor dehydration effect.

[0006] Based on this, the applicant has developed a system that uses dry air to countercurrently heat the canvas, causing the moisture in the canvas to evaporate and transfer upstream step by step, creating a better dehydration effect than a uniform steam supply from a steam source. Summary of the invention

[0007] The technical problem to be solved by the embodiments of the present invention is to provide a canvas dehydration processing system, which dehydrates the continuously transported canvas by heating dry air and heats the canvas step by step in the reverse direction of the canvas, thereby solving the problem of energy waste by using steam sources in commonly used drying devices, and at the same time solving the problem of steam residue in the canvas fabric fibers caused by steam source drying.

[0008] In order to solve the above technical problems, the present invention provides a canvas dehydration processing system, including a dehydration and drying box, wherein a canvas inlet and a canvas outlet are provided in the dehydration and drying box, and the canvas inlet and the canvas outlet are located at both ends of the length direction of the dehydration and drying box, wherein the canvas enters the dehydration and drying box through the canvas inlet, is transmitted in the direction of the canvas outlet, and leaves the dehydration and drying box through the canvas outlet; in the dehydration and drying box, a first dehydration unit, a second dehydration unit, and a third dehydration unit are sequentially arranged along the opposite direction of the canvas transmission direction, wherein the air inlet of the first dehydration unit is connected to the air inlet pipe of the dry air, the air outlet of the first dehydration unit is connected to the air inlet of the second dehydration unit through a first air supply pipeline, the air outlet of the second dehydration unit is connected to the air inlet of the third dehydration unit through a second air supply pipeline, and the air outlet of the third dehydration unit is connected to the air outlet pipe; heating devices are respectively provided in the first dehydration unit, the second dehydration unit, and the third dehydration unit for heating the gas and the canvas.

[0009] The heating device includes an upper heating plate, a lower heating plate, an upper heating rod, and a lower heating rod, wherein the upper heating rod is located on the upper heating plate, and the lower heating rod is located on the lower heating plate; the lower heating plate and the upper heating plate are arranged in parallel to form a dehydration space for heating the canvas therebetween, and a plurality of air holes are respectively provided on the lower heating plate and the upper heating plate to allow gas to flow upward through the air holes.

[0010] The air inlets of the first dehydration unit, the second dehydration unit and the third dehydration unit are all located below the heating device, and the air outlets are all located above the heating device.

[0011] The first gas pipeline and the second gas pipeline are respectively provided with fans to drive the gas of the first dehydration unit to be transported to the second dehydration unit, and the gas of the second dehydration unit to be transported to the third dehydration unit.

[0012] The air inlet pipe is provided with a filter for filtering the dry air and filtering out impurities therein.

[0013] The gas outlet pipe is connected to the gas inlet pipe through a steam-water separator, thereby forming an internal circulation effect of the dry gas.

[0014] Alternatively, the air outlet pipe is directly connected to the steam-water separator, the steam-water separator is not connected to the air inlet pipe, and the air inlet pipe is connected to the environment.

[0015] The first dehydration unit, the second dehydration unit and the third dehydration unit are separated by an incompletely closed partition; incompletely closed means that a gap for the canvas to pass through is retained between two adjacent dehydration units, so two adjacent dehydration units cannot be completely separated by the partition.

[0016] A water squeezing roller device is also provided in front of the canvas entrance of the dehydration and drying box. The upper pressure roller of the water squeezing roller device is a pressure roller, and the lower pressure roller is a support roller. A heating component is provided in the support roller, and the support roller serves as a power roller. A temperature sensor is provided on the output side of the upper pressure roller and the lower pressure roller to detect the temperature T2 of the canvas and determine the moisture content correction value h of the canvas according to the temperature of the canvas, wherein

[0017] h = (T1-T0) 2 / (T2-T0) 2 , where T0 is the temperature of the canvas before entering the squeezing roller device, obtained by detection, T1 is the heating temperature of the squeezing roller device, that is, the surface temperature of the support roller, obtained by detection, and T2 is the temperature of the canvas after passing through the squeezing roller device; the larger the h value, the higher the moisture content, and the smaller the h value, the lower the moisture content;

[0018] The heating power of the heating devices of the second dehydration unit and the third dehydration unit is corrected according to the correction value h to control the dehydration temperature in the two dehydration units.

[0019] The correction method is to adjust the power W2 of the heating device in the second dehydration unit so that the dehydration temperature Tb in the second dehydration unit is T3+10h;

[0020] Adjust the power W3 of the heating device in the third dehydration unit so that the dehydration temperature Tb in the third dehydration unit is T4+15h;

[0021] Wherein T3 is the reference temperature value in the second dehydration unit, and T4 is the reference temperature value in the third dehydration unit.

[0022] The water squeezing roller device also includes a base, a supporting column, an adjusting beam, and a telescopic cylinder. The two ends of the supporting roller are horizontally mounted on the base through supporting shaft seats, and the pressure roller is mounted in the middle of the adjusting beam; the supporting column and the telescopic cylinder are respectively connected to the base and are located on the front and rear sides of the supporting roller; wherein the supporting column is vertically fixed on the base, and the lower end of the telescopic cylinder is rotatably mounted on the base through a hinge seat; one end of the adjusting beam is connected to the supporting column by a rotating connection, and the other end is connected to the cylinder rod of the telescopic cylinder by a rotating connection.

[0023] A pressure sensor is provided between the support shaft seat and the base to detect the change of pressure F between the pressure roller and the support roller.

[0024] The telescopic cylinder is configured to control the pressure F between the pressure roller and the support roller according to the moisture content correction value h, specifically:

[0025] When h>h0, the telescopic cylinder is controlled to contract to increase F, until h≤h0, the telescopic cylinder is controlled to stop contracting, and h0 is the preset value.

[0026] The pressure roller and support roller in the water squeezing roller device are arranged horizontally, with the pressure roller on the left and the support roller on the right. The canvas is allowed to enter between the pressure roller and the support roller from bottom to top, and is output horizontally to the right along the top of the support roller, thereby forming a quarter-circle contact surface between the canvas and the support roller. On the one hand, the water squeezed out of the canvas flows downward naturally, and on the other hand, a longer contact surface and contact time are formed between the support roller and the canvas, so that the support roller has a better heating effect on the canvas.

[0027] The canvas dehydration treatment system of the present invention dries the canvas on one side of the outlet of the dehydration and drying box body with dry air, displaces the water vapor inside the fabric fibers of the canvas, and makes the high-temperature gas inside the fabric fibers of the canvas contain no moisture; at the same time, through the structural design of the first dehydration unit, the second dehydration unit, and the third dehydration unit being connected in series in the opposite direction to the canvas transmission direction, the moisture in the canvas is evaporated, and high-temperature steam is formed in the second dehydration unit and the third dehydration unit, thereby realizing the dehydration treatment of the moisture in the canvas; and further, a water squeezing roller device is designed, and the moisture content reference value of the canvas is determined by detecting the temperature of the canvas behind the water squeezing roller device, and then the dehydration temperature in the dehydration and drying box body is controlled according to the moisture content reference value, so that the moisture in the fabric fibers of the canvas can be dried out to obtain a canvas with almost no residual moisture.

[0028] The conventional water squeezing roller device is arranged horizontally, and the canvas is transported forward horizontally along the water squeezing roller device. This will cause the water squeezed out by the water squeezing roller device to flow downward along the roller located below (usually the lower roller), so the squeezed water is not easy to collect and will pollute the lower roller; at the same time, the canvas only contacts the water squeezing roller device between the rollers, which means that the heating distance and heating time when heated by the water squeezing roller device are very short, and it is difficult to achieve a good preheating effect.

[0029] In this regard, the applicant also provides a canvas dehydration processing system, which includes a water squeezing roller device and a dehydration and drying box. The water squeezing roller device includes a pressure roller and a support roller. The pressure roller and the support roller are arranged horizontally, so that the canvas is transported from bottom to top between the pressure roller and the support roller, and output to the right along the top of the support roller into the dehydration and drying box; a heating element is provided in the support roller for heating the support roller.

[0030] The water squeezing roller device also includes a base, a supporting column, an adjusting beam, a telescopic cylinder and a supporting shaft seat, wherein the base is arranged vertically, the supporting shaft seat is fixed on the side of the base, and the supporting roller is installed on the supporting shaft seat; the telescopic cylinder and the supporting column are located on the upper and lower sides of the supporting shaft seat, and are both connected to the base; the pressure roller is connected to the middle part of the adjusting beam, the lower end of the adjusting beam is connected to the supporting column by a rotating connection, and the upper end of the adjusting beam is connected to the cylinder rod end of the telescopic cylinder by a rotating connection.

[0031] Pressure sensors are also provided on the support shaft seat and the base bracket to detect the horizontal pressure F applied by the support shaft seat to the base, and the pressure F is equal to the pressing force between the pressure roller and the support roller.

[0032] Directly below the support roller and the pressure roller, a guide roller is provided to enable the canvas to pass horizontally through the guide roller and then be transported vertically upward to between the support roller and the pressure roller.

[0033] A water receiving groove is also provided below the guide roller for receiving the water squeezed out by the pressure roller and the support roller.

[0034] A temperature sensor is also provided just above the top of the support roller for detecting the temperature T2 of the upper surface of the canvas conveyed to the top of the support roller.

[0035] When T2+2<T1, the telescopic cylinder is driven to slowly retract the cylinder rod to increase the pressing force between the pressure roller and the support roller;

[0036] When T2+2≥T1>T2+1, the telescopic cylinder is controlled to stop telescoping, and the pressure F at this time is recorded;

[0037] When T2+1≥T1, the telescopic cylinder is controlled to slowly release the cylinder rod to reduce the pressing force between the pressure roller and the support roller.

[0038] The structure of the dehydration and drying box can refer to the structural design of the dehydration and drying box mentioned above.

[0039] The heating devices of the first dehydration unit and the second dehydration unit in the technical solution both use fixed heating powers W1 and W2, and the heating device of the third dehydration unit uses a variable heating power W3, wherein the power of W3 is determined according to the humidity k in the second gas pipeline between the second dehydration unit and the third dehydration unit:

[0040] When the humidity k is greater than the preset value k0, the power of the heating device of the third dehydration unit is controlled to increase, so that the humidity k decreases, until the humidity k does not exceed the preset value k0, the power of the heating device of the fourth dehydration unit is kept unchanged;

[0041] When the humidity k is less than a preset value k1, the heating power of the third dehydration unit is controlled to decrease so as to increase the humidity, wherein k1<k0.

[0042] The values ​​of k0 and k1 can be 70%, 65%, or 65%, 60%.

[0043] On the one hand, the present invention uses normal temperature and dry air as the drying air source, saving the energy consumption of the steam generator; and further, by heating with a pressure roller to sense the temperature, the moisture content of the canvas can be controlled before it enters the dehydration and drying box, so that there is no need to use a complicated temperature control method for the three dehydration units, and only the power of the heating device in the third dehydration unit needs to be adjusted to meet the drying requirements, thereby achieving the effect of energy saving and optimization, and avoiding the problem of excessive energy consumption for over-drying during the drying process; in addition, since the three-stage dehydration unit of the dehydration and drying box uses an airflow control method opposite to the canvas conveying direction, the outlet end of the dehydration and drying box uses dry air to replace the high-temperature steam in the fiber gaps of the canvas fabric, so that the canvas will not condense to form residual moisture after leaving the dehydration and drying box and coming into contact with the normal temperature environment.

[0044] In order to solve the temperature control problem of the canvas dehydration processing system, in particular, to formulate a temperature control strategy for the dehydration and drying box according to the moisture content of the canvas, so that the canvas can be completely dehydrated in the most energy-saving way, the present invention also provides a temperature control method for the dehydration and drying box, which includes:

[0045] Step 1: providing a water squeezing roller device for squeezing the canvas to squeeze out some of the water in the canvas, and then sequentially conveying the canvas to the third dehydration unit, the second dehydration unit and the first dehydration unit in the dehydration and drying box;

[0046] Step 2, obtaining the canvas temperature T0 before entering the water squeezing roller device, the heating temperature T1 of the water squeezing roller device, and the canvas temperature T2 after being heated by the water squeezing roller device;

[0047] Step 3: According to the temperature change of the canvas, evaluate the moisture content of the canvas and determine the moisture content correction value h;

[0048] Step 4: according to the moisture content correction value, determine whether the moisture content of the canvas after passing through the water squeezing roller device is higher than the preset value h0; if it is higher than the preset value h0, increase the water squeezing pressure of the water squeezing roller device, so that the moisture content correction value is lower than the preset value h0;

[0049] Step 5: Determine the dehydration temperature of the third dehydration unit and the second dehydration unit according to the moisture content correction value.

[0050] In step 3, h = (T1-T0) 2 / (T2-T0) 2 , where T0, T1, and T2 are detected by temperature sensors respectively; the larger the h value, the higher the moisture content, and the smaller the h value, the lower the moisture content.

[0051] Step 4 also includes: when h>h0, controlling the telescopic cylinder to contract so that the pressure F between the pressure roller and the support roller increases, until h≤h0, controlling the telescopic cylinder to stop contracting.

[0052] Step five includes correcting the heating power of the heating devices of the second dehydration unit and the third dehydration unit according to the correction value h to control the dehydration temperature in the two dehydration units.

[0053] The correction method is to adjust the power W2 of the heating device in the second dehydration unit so that the dehydration temperature Tb in the second dehydration unit is T3+10h;

[0054] Adjust the power W3 of the heating device in the third dehydration unit so that the dehydration temperature Tb in the third dehydration unit is T4+15h;

[0055] Wherein T3 is the reference temperature value in the second dehydration unit, and T4 is the reference temperature value in the third dehydration unit.

[0056] The temperature control method of the dehydration and drying box provided by the present invention evaluates the moisture content of the canvas after extrusion by means of the squeezing and heating temperature changes of the canvas by the squeezing roller device, thereby determining the squeezing force and the dehydration temperature control strategy of the dehydration and drying box; the moisture in the canvas is completely dried at the minimum cost, and combined with the gas circulation path of the dehydration and drying box (the reverse flow mode of the dry air), the canvas can achieve the best drying effect, so that no steam moisture remains in the gaps between the canvas fabric fibers after drying. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a structural schematic diagram of the canvas dehydration processing system;

[0058] Figure 2 It is a schematic diagram of three dehydration units and the direction of canvas in the canvas dehydration treatment system;

[0059] Figure 3 A schematic diagram of an implementation of a water squeezing roller device;

[0060] Figure 4 For Figure 3 A schematic structural diagram of a canvas dewatering system of a water squeezing roller device as shown;

[0061] Figure 5 For Figure 4 Schematic diagram of the canvas dehydration processing system shown.

[0062] In the figure: 1-dehydration and drying box; 1a-canvas inlet; 1b-canvas outlet;

[0063] 11-first dehydration unit; 11a-air inlet of the first dehydration unit; 11b-air outlet of the first dehydration unit;

[0064] 12-second dehydration unit; 12a-air inlet of the second dehydration unit; 12b-air outlet of the second dehydration unit;

[0065] 13-the third dehydration unit; 13a-the air inlet of the third dehydration unit; 13b-the air outlet of the third dehydration unit;

[0066] 14-intake pipe;

[0067] 15- first gas transmission pipeline;

[0068] 16- second gas transmission pipeline;

[0069] 17-exhaust pipe;

[0070] 18-heating device; 18a-upper heating plate; 18b-lower heating plate; 18c-upper heating rod; 18d-lower heating rod;

[0071] 19-partition;

[0072] 2-water squeezing roller device; 21-pressure roller; 22-support roller; 23-base; 24-support column; 25-adjusting beam; 26-telescopic cylinder; 27-support shaft seat;

[0073] 3- Canvas. DETAILED DESCRIPTION

[0074] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings; in the following description, many specific details are elaborated to facilitate a full understanding of the present invention; however, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited to the specific embodiments disclosed below.

[0075] When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be an intermediate element at the same time; the terms "vertical", "horizontal", "left", "right" and the like used in this document are for illustrative purposes only.

[0076] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0077] Embodiment 1: Combination Figure 1-2 As shown, the present invention provides a canvas dehydration processing system, including a dehydration and drying box 1, wherein a canvas inlet 1a and a canvas outlet 1b are provided in the dehydration and drying box 1, and the canvas inlet 1a and the canvas outlet 1b are located at both ends of the length direction of the dehydration and drying box 1, wherein the canvas 3 enters the dehydration and drying box 1 through the canvas inlet 1a, is transmitted in the direction of the canvas outlet 1b, and leaves the dehydration and drying box 1 through the canvas outlet 1b; the dehydration and drying box 1 is in the shape of a rectangular parallelepiped as a whole, and the side walls of the dehydration and drying box 1 are designed with heat insulation, the canvas inlet 1a is arranged on the left side of the dehydration and drying box 1, and the canvas outlet 1b is arranged on the right side of the dehydration and drying box 1, and the canvas inlet 1a and the canvas outlet 1b are located at the same horizontal height, so that the canvas 3 can be horizontally transmitted inside the dehydration and drying box 1.

[0078] In the dehydration and drying box 1, along the opposite direction of the transmission direction of the canvas 3 (since the transmission direction of the canvas is from left to right, the opposite direction of the transmission direction is the direction from right to left as shown in the figure), a first dehydration unit 11, a second dehydration unit 12, and a third dehydration unit 13 are arranged in sequence, wherein the air inlet 11a of the first dehydration unit is connected with the air inlet pipe 14 of the dry air, the air outlet 11b of the first dehydration unit is connected with the air inlet 12a of the second dehydration unit through the first air supply pipeline 15, the air outlet 12b of the second dehydration unit is connected with the air inlet 13a of the third dehydration unit through the second air supply pipeline 16, and the air outlet 13b of the third dehydration unit is connected with the air outlet pipe 17; heating devices 18 are respectively provided in the first dehydration unit 11, the second dehydration unit 12, and the third dehydration unit 13 for heating the gas and the canvas 3.

[0079] The first gas pipeline 15 and the second gas pipeline 16 can be independent pipeline structures or gas transmission channel structures designed to be attached to the outer wall or inner wall of the dehydration and drying box 1; a heating device 18 is respectively arranged inside each dehydration unit to heat the gas and canvas inside the dehydration unit, wherein the purpose of the heating device 18 heating the gas is also to transfer heat to the canvas; since the first dehydration unit 11 is connected to the dry air inlet pipe 14, the gas entering the first dehydration unit 11 is mainly dry gas, which is heated by the heating device 18 and then rushed upward to the canvas 3 by the heated gas, replacing the steam in the gaps of the fabric fibers of the canvas 3, so that the air inside the first dehydration unit 11 has a certain water content, that is, primary steam with a lower concentration.

[0080] The primary steam enters the first gas pipeline 15 through the gas outlet 11b of the first dehydration unit, and is transported to the gas inlet 12a of the second dehydration unit by the first gas pipeline 15, and enters the second dehydration unit 12 through the gas inlet 12a of the second dehydration unit. The primary steam is heated again by the heating device 18 in the second dehydration unit 12, so that the temperature of the primary steam is further increased, and it rushes to the canvas again to evaporate the moisture in the canvas 3, thereby obtaining secondary steam with relatively high concentration and temperature; in this process, the moisture in the canvas 3 is evaporated more efficiently, so that the moisture content in the canvas 3 is reduced.

[0081] The secondary steam enters the second gas pipeline 16 through the gas outlet 12b of the second dehydration unit, and is transported to the gas inlet 13a of the third dehydration unit by the second gas pipeline 16, and enters the third dehydration unit 13 through the gas inlet 13a of the third dehydration unit, and is further heated by the heating device 18 in the third dehydration unit 13, so that the temperature of the secondary steam is further increased, and rushes to the canvas 3, so that the canvas is heated and the moisture in the canvas 3 evaporates more efficiently, so that the moisture content in the canvas 3 is rapidly reduced.

[0082] The above is an explanation of the working process and principle of the three dehydration units based on the air flow direction; if canvas 3 is taken as the main body, the process is:

[0083] First, the canvas 3 first enters the third dehydration unit 13, and is heated by the heating device and high-temperature steam in the third dehydration unit 13, so that the water in the canvas 3 evaporates quickly and enters the outlet pipe 17 through the outlet 13b of the third dehydration unit;

[0084] Then, the canvas 3 enters the second dehydration unit 12 adjacent thereto from the third dehydration unit 13, and continues to be heated by steam and the heating device 18 in the second dehydration unit 12; since the air humidity in the second dehydration unit 12 is much lower than the air humidity in the third dehydration unit 13, although the temperature of the canvas 3 in the second dehydration unit 12 is lower than that in the third dehydration unit, the water in the canvas 3 can still be evaporated at a relatively fast rate. After the canvas 3 has undergone the high-temperature dehydration in the third dehydration unit 13, it undergoes the medium-temperature dehydration in the second dehydration unit 12 again (the high temperature, medium temperature and the low temperature of the first dehydration unit are all relatively high and low temperatures, not high temperature and low temperature in an absolute sense), and most of the water has been evaporated. However, since the steam in the second dehydration unit has a certain water content, the second dehydration unit cannot completely dry the water in the gaps between the fibers of the canvas fabric;

[0085] Finally, the canvas enters the first dehydration unit 11 from the second dehydration unit 12. The temperature of the first dehydration unit is lower than that of the second dehydration unit, but the advantage of the first dehydration unit is that the gas entering the first dehydration unit through the air inlet is dry air, so the dry air is heated by the heating device and then rushed onto the canvas 3, thereby replacing the water vapor in the gaps between the fabric fibers of the canvas 3, thereby achieving full drying of the canvas.

[0086] The heating device 18 includes an upper heating plate 18a, a lower heating plate 18b, an upper heating rod 18c, and a lower heating rod 18d, wherein the upper heating rod 18c is located on the upper heating plate 18a, and the lower heating rod 18d is located on the lower heating plate 18b; the lower heating plate 18b and the upper heating plate 18a are arranged in parallel to form a dehydration space for heating the canvas therebetween, and a plurality of air holes are respectively provided on the lower heating plate 18b and the upper heating plate 18a to allow gas to flow upward through the air holes.

[0087] There are multiple upper heating rods 18c and lower heating rods 18d respectively, and they are arranged in a uniform distribution manner; corresponding to the installation positions of the upper heating rods 18c and the lower heating rods 18d, the upper heating plates 18a and the lower heating plates 18b are provided with upward or downward concave groove structures to accommodate the upper heating rods 18c and the lower heating rods 18d; at the same time, the outer parts of the upper heating plates 18a and the lower heating plates 18b are covered by an outer cover structure to prevent the upper heating plates 18a and the lower heating plates 18b from directly contacting the canvas, so that the upper heating plates 18a and the lower heating plates 18b will not burn the canvas.

[0088] The air inlet 11a of the first dehydration unit, the air inlet 12a of the second dehydration unit, and the air inlet 13a of the third dehydration unit are all located below the heating device, and the air outlet 11b of the first dehydration unit, the air outlet 12b of the second dehydration unit, and the air outlet 13b of the third dehydration unit are all located above the heating device 18.

[0089] The air inlets of all the dehydration units in the present invention are located at the bottom, and the air outlets of all the dehydration units are located at the top, so that an ascending high-temperature airflow is formed inside each dehydration unit. The ascending airflow impacts the canvas, so that the moisture in the canvas evaporates quickly, achieving a better drying effect.

[0090] The first gas pipeline 15 and the second gas pipeline 16 are respectively provided with fans (not shown in the figure) to drive the gas from the first dehydration unit 11 to be transported to the second dehydration unit 12 , and the gas from the second dehydration unit 12 to be transported to the third dehydration unit 13 .

[0091] The air inlet pipe 14 is provided with a filter (not shown in the figure) for filtering the dry air and removing impurities therein.

[0092] The gas outlet pipe 17 is connected to the gas inlet pipe through a steam-water separator (not shown in the figure), thereby forming an internal circulation effect of the dry gas.

[0093] Alternatively, the air outlet pipe 17 is directly connected to a steam-water separator (not shown in the figure), the steam-water separator is not connected to the air inlet pipe 14, and the air inlet pipe 14 is connected to the environment.

[0094] The first dehydration unit 11, the second dehydration unit 12, and the third dehydration unit 13 are separated by an incompletely closed partition 19; incompletely closed means that a gap for the canvas to pass through is retained between two adjacent dehydration units, so two adjacent dehydration units cannot be completely separated by the partition.

[0095] like Figure 1 As shown, a water squeezing roller device 2 is also provided in front of the canvas inlet 1a of the dehydration and drying box body, the upper pressing roller of the water squeezing roller device 2 is a pressure roller 21, and the lower pressing roller is a support roller 22. A heating component is provided in the support roller 22, and the support roller 22 serves as a power roller (driven by an independent motor and a reducer). The linear speed of the support roller 22 is the same as the conveying speed of the canvas 3. A temperature sensor (not shown in the figure) is provided on the output side of the upper pressing roller and the lower pressing roller for detecting the temperature T2 of the canvas 3 and determining the moisture content correction value h of the canvas according to the temperature of the canvas, wherein

[0096] h = (T1-T0) 2 / (T2-T0) 2, where T0 is the temperature of the canvas before entering the water squeezing roller device, obtained by detection, T1 is the heating temperature of the water squeezing roller device, that is, the surface temperature of the support roller, obtained by detection, and T2 is the temperature of the canvas after passing through the water squeezing roller device; the moisture content correction value h represents the relationship between the temperature rise amplitude of the canvas after passing through the water squeezing roller device and the moisture content of the canvas. The higher the moisture content of the canvas, the smaller the temperature rise amplitude, and the lower the moisture content of the canvas, the greater the temperature rise amplitude; the larger the h value, the higher the moisture content, and the smaller the h value, the lower the moisture content; accordingly, the higher the moisture content of the canvas, the greater the dehydration pressure of the dehydration and drying box, and a higher dehydration temperature needs to be used, so that the control strategy for the heating power of the heating device can be formulated according to the moisture content correction value; specifically:

[0097] According to the correction value h, the heating power of the heating device of the second dehydration unit 12 and the third dehydration unit 13 is corrected to control the dehydration temperature in the two dehydration units; the reason why the heating device of the second dehydration unit 12 and the third dehydration unit 13 is controlled here but the heating device of the first dehydration unit 11 is not controlled is because after the two-stage high-temperature dehydration of the second dehydration unit 12 and the third dehydration unit 13, when the canvas reaches the first dehydration unit 11, its moisture content is already very low. As long as the heating power of the heating device in the second dehydration unit 12 and the third dehydration unit 13 is reasonably controlled, the first dehydration unit 11 can achieve the replacement of the steam in the canvas fabric fibers in the most economical heating method.

[0098] The correction method is to adjust the power W2 of the heating device in the second dehydration unit 12 so that the dehydration temperature Tb in the second dehydration unit 12 is T3+10h;

[0099] Adjust the power W3 of the heating device in the third dehydration unit 13 so that the dehydration temperature Tb in the third dehydration unit 13 is T4+15h;

[0100] Wherein T3 is the reference temperature value in the second dehydration unit 12 , and T4 is the reference temperature value in the third dehydration unit 13 .

[0101] The water squeezing roller device 2 also includes a base 23, a supporting column 24, an adjusting beam 25, and a telescopic cylinder 26. The two ends of the supporting roller 22 are horizontally installed on the base 23 through a supporting shaft seat 27, and the pressure roller 21 is installed in the middle of the adjusting beam 25; the supporting column 24 and the telescopic cylinder 26 are respectively connected to the base 23 and are located on the front and rear sides of the supporting roller 22; wherein the supporting column 24 is vertically fixed on the base 23, and the lower end of the telescopic cylinder 26 is rotatably installed on the base 23 through a hinge seat; one end of the adjusting beam 25 is connected to the supporting column 24 by a rotating connection, and the other end is connected to the cylinder rod of the telescopic cylinder 26 by a rotating connection.

[0102] A pressure sensor is provided between the support shaft seat 27 and the base to detect the change of the pressure F between the pressure roller and the support roller.

[0103] The telescopic cylinder 26 is configured to control the pressure F between the pressure roller and the support roller according to the moisture content correction value h, specifically:

[0104] When h>h0, the telescopic cylinder is controlled to contract to increase F, until h≤h0, the telescopic cylinder is controlled to stop contracting, and h0 is the preset value.

[0105] like Figure 3-4 As shown, the pressure roller 21 and the support roller 22 in the water squeezing roller device 2 are arranged horizontally, with the pressure roller 21 on the left and the support roller 22 on the right, and the canvas 3 enters between the pressure roller 21 and the support roller 22 from bottom to top, and is output horizontally to the right along the top of the support roller 22, thereby forming a quarter-circle contact surface between the canvas 3 and the support roller. On the one hand, the water squeezed out of the canvas 3 flows downward naturally, and on the other hand, a longer contact surface and contact time are formed between the support roller 22 and the canvas 3, and the support roller 22 has a better heating effect on the canvas.

[0106] The canvas dehydration treatment system of the present invention dries the canvas on one side of the outlet of the dehydration and drying box body with dry air, displaces the water vapor inside the fabric fibers of the canvas, and makes the high-temperature gas inside the fabric fibers of the canvas contain no moisture; at the same time, through the structural design of the first dehydration unit, the second dehydration unit, and the third dehydration unit being connected in series in the opposite direction to the canvas transmission direction, the moisture in the canvas is evaporated, and high-temperature steam is formed in the second dehydration unit and the third dehydration unit, thereby realizing the dehydration treatment of the moisture in the canvas; and further, a water squeezing roller device is designed, and the moisture content reference value of the canvas is determined by detecting the temperature of the canvas behind the water squeezing roller device, and then the dehydration temperature in the dehydration and drying box body is controlled according to the moisture content reference value, so that the moisture in the fabric fibers of the canvas can be dried out to obtain a canvas with almost no residual moisture.

[0107] Embodiment 2: In combination with the above embodiment 1, the present invention further provides a temperature control method for a dehydration and drying box, which comprises:

[0108] Step 1: providing a water squeezing roller device for squeezing the canvas to squeeze out some of the water in the canvas, and then sequentially conveying the canvas to the third dehydration unit, the second dehydration unit and the first dehydration unit in the dehydration and drying box;

[0109] Step 2, obtaining the canvas temperature T0 before entering the water squeezing roller device, the heating temperature T1 of the water squeezing roller device, and the canvas temperature T2 after being heated by the water squeezing roller device;

[0110] Step 3: According to the temperature change of the canvas, evaluate the moisture content of the canvas and determine the moisture content correction value h;

[0111] Step 4: according to the moisture content correction value, determine whether the moisture content of the canvas after passing through the water squeezing roller device is higher than the preset value h0; if it is higher than the preset value h0, increase the water squeezing pressure of the water squeezing roller device, so that the moisture content correction value is lower than the preset value h0;

[0112] Step 5: Determine the dehydration temperature of the third dehydration unit and the second dehydration unit according to the moisture content correction value.

[0113] In step 3, h = (T1-T0) 2 / (T2-T0) 2 , where T0, T1, and T2 are detected by temperature sensors respectively; the larger the h value, the higher the moisture content, and the smaller the h value, the lower the moisture content.

[0114] Step 4 also includes: when h>h0, controlling the telescopic cylinder to contract so that the pressure F between the pressure roller and the support roller increases, until h≤h0, controlling the telescopic cylinder to stop contracting.

[0115] Step five includes correcting the heating power of the heating devices of the second dehydration unit and the third dehydration unit according to the correction value h to control the dehydration temperature in the two dehydration units.

[0116] The correction method is to adjust the power W2 of the heating device in the second dehydration unit so that the dehydration temperature Tb in the second dehydration unit is T3+10h;

[0117] Adjust the power W3 of the heating device in the third dehydration unit so that the dehydration temperature Tb in the third dehydration unit is T4+15h;

[0118] Wherein T3 is the reference temperature value in the second dehydration unit, and T4 is the reference temperature value in the third dehydration unit.

[0119] The temperature control method of the dehydration and drying box provided by the present invention evaluates the moisture content of the canvas after extrusion by means of the squeezing and heating temperature changes of the canvas by the squeezing roller device, thereby determining the squeezing force and the dehydration temperature control strategy of the dehydration and drying box; the moisture in the canvas is completely dried at the minimum cost, and combined with the gas circulation path of the dehydration and drying box (the reverse flow mode of the dry air), the canvas can achieve the best drying effect, so that no steam moisture remains in the gaps between the canvas fabric fibers after drying.

[0120] Embodiment 3: Figure 3-5 As shown, on the basis of the first embodiment, the present invention further provides a canvas dehydration processing system, which includes a water squeezing roller device 2 and a dehydration drying box 1, the water squeezing roller device 2 includes a pressure roller 21 and a support roller 22, the pressure roller 21 and the support roller 22 are arranged horizontally, so that the canvas 3 is transported from bottom to top between the pressure roller 21 and the support roller 22, and output to the right along the top of the support roller 22 into the dehydration drying box 1; wherein a heating element is provided in the support roller 22 for heating the support roller 22, the heating element is electrically heated, has a plurality of elements, and is evenly distributed inside the support roller 22, and a conductive slip ring is provided at the end of the support roller, so that a stable power supply can be achieved during the rotation process (the heating function of the support roller can adopt a conventional heating roller structure, for example, it can also be as patent publication No. CN101407096B A heating method for a heating roller and a heating roller using liquid heating oil, or patent publication No. CN109927331B The water squeezing roller device 2 in this embodiment is similar in structure to that in the first embodiment, but is installed in a different manner. The water squeezing roller device in the first embodiment is placed horizontally, and the canvas 3 passes through the water squeezing roller device horizontally; the water squeezing roller device 2 in this embodiment is arranged vertically, and the canvas 3 is transmitted vertically upward through the water squeezing roller device 2, and then transmitted horizontally to the right along the support roller 22; therefore, the base 23 and the adjusting beam 25 in this embodiment are arranged vertically, and the supporting column 24 and the telescopic cylinder 26 are arranged horizontally; since the supporting column 24 needs to withstand vertical pressure, during implementation, the supporting column 24 may be provided with an inclined support rod obliquely supported on the base 23 to maintain the horizontal state of the supporting column 24.

[0121] The water squeezing roller device 2 also includes a base 23, a supporting column 24, an adjusting beam 25, a telescopic cylinder 26 and a supporting shaft seat 27, wherein the base 23 is arranged vertically, the supporting shaft seat 27 is fixed on the side of the base 23, and the supporting roller 22 is installed on the supporting shaft seat 27; the telescopic cylinder 26 and the supporting column 24 are located on the upper and lower sides of the supporting shaft seat 27, and are both connected to the base 23; the pressure roller 21 is connected to the middle part of the adjusting beam 25, the lower end of the adjusting beam 25 is connected to the supporting column 24 by a rotating connection, and the upper end of the adjusting beam 25 is connected to the cylinder rod end of the telescopic cylinder 26 by a rotating connection.

[0122] Pressure sensors are also provided on the support shaft seat 27 and the base 23 bracket to detect the horizontal pressure F applied by the support shaft seat 27 to the base 23 , and the pressure F is equal to the pressing force between the pressure roller 21 and the support roller 22 .

[0123] A guide roller is provided directly below the support roller 22 and the pressure roller 21 , so that the canvas can be transported vertically upward to between the support roller 22 and the pressure roller 21 after passing the guide roller horizontally.

[0124] A water receiving groove is also provided below the guide roller for receiving the water squeezed out by the pressure roller 21 and the support roller 22 .

[0125] A temperature sensor is also provided directly above the top of the support roller 22 for detecting the temperature T2 of the upper surface of the canvas 3 conveyed to the top of the support roller 22 .

[0126] The support roller 22 is used as a power roller, and its linear speed of rotation is the same as the conveying speed of the canvas, and it maintains a uniform motion. Under this premise, the control method of the telescopic cylinder 26 is as follows:

[0127] When T2+2<T1, the telescopic cylinder 26 is driven to slowly retract the cylinder rod so as to increase the pressing force between the pressure roller 21 and the support roller 22;

[0128] When T2+2≥T1>T2+1, the telescopic cylinder 26 is controlled to stop telescoping, and the pressure F at this time is recorded;

[0129] When T2+1≥T1, the telescopic cylinder 26 is controlled to slowly release the cylinder rod so that the pressing force between the pressure roller 21 and the support roller 22 is reduced.

[0130] The canvas is dehydrated by controlling the appropriate pressing force through the telescopic cylinder. By detecting the surface temperature T2 of the canvas, it is inferred whether the moisture content of the canvas has reached the appropriate range. After the canvas enters the dehydration and drying box, it can be dried and dehydrated in the most economical way, without residual moisture while ensuring the properties of the canvas material itself.

[0131] Since canvases of different materials have different water absorption and water storage capacities and different thicknesses, the degree of water squeezing and thermal conductivity are also different. Therefore, when dehydrating canvases of different materials, thicknesses, and moisture contents, they need to be treated differently. The purpose of the treatment is to use the most economical and energy-saving method to dehydrate and dry the canvas, and to ensure that there are no condensed water droplets in the gaps between the canvas fabric fibers after drying.

[0132] The structure of the dehydration and drying box 1 can refer to the structural design of the dehydration and drying box 1 mentioned above.

[0133] The heating devices of the first dehydration unit 11 and the second dehydration unit 12 in the technical solution both use fixed heating powers W1 and W2, and the heating device of the third dehydration unit uses a variable heating power W3, wherein the power of W3 is determined according to the humidity k in the second gas pipeline 16 between the second dehydration unit 12 and the third dehydration unit 13 (one or more humidity sensors are provided in the second gas pipeline 16):

[0134] When the humidity k is greater than the preset value k0, the power of the heating device of the third dehydration unit 13 is controlled to increase, so that the humidity k decreases, until the humidity k does not exceed the preset value k0, the power of the heating device of the third dehydration unit is kept unchanged;

[0135] When the humidity k is less than a preset value k1, the heating power of the third dehydration unit is controlled to decrease so as to increase the humidity, wherein k1<k0.

[0136] The values ​​of k0 and k1 may be 70%, 65%, or 65%, 60%. That is, the difference between the values ​​of k0 and k1 may usually be about 5%. The difference may also be adjusted according to actual usage, for example, to 2% or 3%.

[0137] On the one hand, the present invention uses normal temperature and dry air as the drying air source, saving the energy consumption of the steam generator; and further, by heating with a pressure roller to sense the temperature, the moisture content of the canvas can be controlled before entering the dehydration and drying box 1, so that there is no need to use a complicated temperature control method for the three dehydration units, and only the power of the heating device in the third dehydration unit needs to be adjusted to meet the drying requirements, thereby achieving the effect of energy saving and optimization, and avoiding the problem of excessive energy consumption for over-drying during the drying process; in addition, since the three-stage dehydration unit of the dehydration and drying box 1 uses an airflow control method opposite to the canvas conveying direction, the outlet end of the dehydration and drying box 1 uses dry air to replace the high-temperature steam in the fiber gaps of the canvas fabric, so that the canvas will not condense to form residual moisture after leaving the dehydration and drying box 1 and coming into contact with the normal temperature environment.

[0138] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0139] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be based on the attached claims.

Claims

1. Canvas dehydration system, characterized in that: It comprises a dehydration and drying box, wherein a canvas inlet and a canvas outlet are provided in the dehydration and drying box, and the canvas inlet and the canvas outlet are located at two ends of the length direction of the dehydration and drying box, wherein the canvas enters the dehydration and drying box through the canvas inlet, is transmitted in the direction of the canvas outlet, and leaves the dehydration and drying box through the canvas outlet; in the dehydration and drying box, a first dehydration unit, a second dehydration unit, and a third dehydration unit are sequentially arranged along the opposite direction of the canvas transmission direction, wherein the air inlet of the first dehydration unit is connected with the air inlet pipe of the dry air, the air outlet of the first dehydration unit is connected with the air inlet of the second dehydration unit through the first air transmission pipeline, the air outlet of the second dehydration unit is connected with the air inlet of the third dehydration unit through the second air transmission pipeline, and the air outlet of the third dehydration unit is connected with the air outlet pipe; heating devices are respectively arranged in the first dehydration unit, the second dehydration unit, and the third dehydration unit for heating the gas and the canvas; The heating device comprises an upper heating plate, a lower heating plate, an upper heating rod and a lower heating rod, wherein the upper heating rod is located on the upper heating plate and the lower heating rod is located on the lower heating plate; the lower heating plate and the upper heating plate are arranged in parallel to form a dehydration space for heating the canvas therebetween, and a plurality of air holes are respectively provided on the lower heating plate and the upper heating plate to allow gas to flow upward through the air holes; The air inlets of the first dehydration unit, the second dehydration unit and the third dehydration unit are all located below the heating device, and the air outlets are all located above the heating device; A water squeezing roller device is also provided in front of the canvas entrance of the dehydration and drying box. The upper pressure roller of the water squeezing roller device is a pressure roller, and the lower pressure roller is a support roller. A heating component is provided in the support roller, and the support roller serves as a power roller. A temperature sensor is provided on the output side of the upper pressure roller and the lower pressure roller to detect the temperature T2 of the canvas and determine the moisture content correction value h of the canvas according to the temperature of the canvas, wherein h = (T1-T0) 2 / (T2-T0) 2 , where T0 is the temperature of the canvas before entering the squeezing roller device, obtained by detection, T1 is the heating temperature of the squeezing roller device, that is, the surface temperature of the support roller, obtained by detection, and T2 is the temperature of the canvas after passing through the squeezing roller device; the larger the h value, the higher the moisture content, and the smaller the h value, the lower the moisture content; and correcting the heating power of the heating devices of the second dehydration unit and the third dehydration unit according to the correction value h, so as to control the dehydration temperature in the two dehydration units; The telescopic cylinder provided in the water squeezing roller device is configured to control the pressure F between the pressure roller and the support roller according to the moisture content correction value h, specifically: When h>h0, the telescopic cylinder is controlled to contract to increase F, until h≤h0, the telescopic cylinder is controlled to stop contracting, and h0 is the preset value.

2. The canvas dehydration system according to claim 1, characterized in that: The first gas pipeline and the second gas pipeline are respectively provided with fans to drive the gas of the first dehydration unit to be transported to the second dehydration unit, and the gas of the second dehydration unit to be transported to the third dehydration unit.

3. The canvas dehydration system according to claim 1, characterized in that: The air inlet pipe is provided with a filter for filtering the dry air and filtering out impurities therein.

4. The canvas dehydration system according to claim 1, characterized in that: The gas outlet pipe is connected to the gas inlet pipe through a steam-water separator, thereby forming an internal circulation effect of the dry gas.

5. The canvas dehydration system according to claim 1, characterized in that: Alternatively, the air outlet pipe is directly connected to the steam-water separator, the steam-water separator is not connected to the air inlet pipe, and the air inlet pipe is connected to the environment.

6. The canvas dehydration system according to claim 1, characterized in that: The first dehydration unit, the second dehydration unit and the third dehydration unit are separated by an incompletely closed partition; incompletely closed means that a gap for the canvas to pass through is retained between two adjacent dehydration units, so two adjacent dehydration units cannot be completely separated by the partition.

7. The canvas dehydration system according to claim 1, characterized in that: The correction method is to adjust the power W2 of the heating device in the second dehydration unit so that the dehydration temperature Tb in the second dehydration unit is T3+10h; Adjust the power W3 of the heating device in the third dehydration unit so that the dehydration temperature Tb in the third dehydration unit is T4+15h; Wherein T3 is the reference temperature value in the second dehydration unit, and T4 is the reference temperature value in the third dehydration unit.

8. The canvas dehydration system according to claim 1, characterized in that: The water squeezing roller device also includes a base, a supporting column, an adjusting beam, and a telescopic cylinder. The two ends of the supporting roller are horizontally mounted on the base through supporting shaft seats, and the pressure roller is mounted in the middle of the adjusting beam; the supporting column and the telescopic cylinder are respectively connected to the base and are located on the front and rear sides of the supporting roller; wherein the supporting column is vertically fixed on the base, and the lower end of the telescopic cylinder is rotatably mounted on the base through a hinge seat; one end of the adjusting beam is connected to the supporting column by a rotating connection, and the other end is connected to the cylinder rod of the telescopic cylinder by a rotating connection.

9. The canvas dehydration system according to claim 8, characterized in that: A pressure sensor is provided between the support shaft seat and the base to detect the change of pressure F between the pressure roller and the support roller.

10. The canvas dehydration system according to claim 8, characterized in that: The pressure roller and support roller in the water squeezing roller device are arranged horizontally, with the pressure roller on the left and the support roller on the right. The canvas is allowed to enter between the pressure roller and the support roller from bottom to top, and is output horizontally to the right along the top of the support roller, thereby forming a quarter-circle contact surface between the canvas and the support roller. On the one hand, the water squeezed out of the canvas flows downward naturally, and on the other hand, a longer contact surface and contact time are formed between the support roller and the canvas, so that the support roller has a better heating effect on the canvas.

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