A drying system and treatment method for secondary drying of silica gel

Abstract

The present invention discloses a drying system and a processing method for secondary drying of silica gel. The drying system includes a first silo, a drying tank group, a heating component, a pneumatic conveying tank, a second silo, a vibrating screen, a color sorter and a third silo. By setting a drying tank group, the drying tank group includes a first drying tank and a second drying tank, the first drying tank and the second drying tank are connected to the second air inlet through a first air outlet, and a second air outlet is set in the second drying tank, and the hot air is circulated and conveyed to the heat exchanger, thereby realizing the recycling of the hot air, reducing the exhaust volume, and improving the utilization rate of the hot air. At the same time, the heat exchange temperature of the heat exchanger can be set according to actual needs. It can be used for secondary drying of silica gel particle products, can achieve uniform product low moisture content requirements, reduce silica gel surface wear, improve product appearance integrity, controllable product quality, and low investment cost.

Description

Technical Field

[0001] The present invention relates to the technical field of silica gel desiccant production, and in particular to a drying system and a processing method for secondary drying of silica gel. Background Art

[0002] Silica gel desiccant, with a transparent or translucent glassy appearance, is primarily composed of silicon dioxide with the chemical formula mSiO2·nH2O. It is insoluble in water and all solvents, non-toxic and odorless, chemically stable, and unreactive with all substances except strong alkalis and hydrofluoric acid. The silica gel production process primarily involves a synthesis reaction using sodium silicate and sulfuric acid, followed by a series of steps including aging, acid soaking, washing, drying, and screening. Industrial drying processes primarily utilize tunnel drying kilns and mesh belt dryers, primarily for drying semi-finished silica gel with a moisture content of 75-82%. The former has a lower level of automation, requires more labor, consumes more steam, takes longer to dry, and requires a larger floor space. The latter offers a higher level of automation and lower labor intensity, but also requires more investment, suffers from uneven drying, and exhibits a high degree of product breakage.

[0003] Application number CN201610090696.0, titled "Continuous Drying System for Silica Gel Production," utilizes a multi-layer belt dryer controlled by automated electrical instrumentation. Application number CN201821042860.1, titled "A Fully Automatic Discharging System for a Drying Kiln for Silica Gel Production," utilizes a tunnel drying kiln system. This complex structure is generally suitable for large-scale production lines.

[0004] Due to the wide variety of silica gel desiccant products, silica gel with a moisture content of around 5% is often subjected to secondary drying to produce products with a moisture content of less than 2%. For special products, color-changing silica gel, due to moisture absorption and contamination, reaches a saturated moisture content of around 28-30%, requiring drying to a level of less than 2-5%. However, due to limited market demand, large-scale drying equipment is not suitable for production. Instead, production requires equipment with lower drying capacity and a high level of automation. Summary of the Invention

[0005] In view of this, the object of the present invention is to provide a drying system and a treatment method for secondary drying of silica gel.

[0006] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0007] In a first aspect, the present invention provides a drying system for secondary drying of silica gel, comprising a first silo, a drying tank group, a heating component, a pneumatic conveying tank, a second silo, a vibrating screen, a color sorter and a third silo, wherein the first silo contains silica gel material; the drying tank group comprises a first drying tank and a second drying tank, the first drying tank has a first feed port, a first discharge port, a first air inlet and a first air outlet, the second drying tank has a second feed port, a second discharge port, a second air inlet, a second air outlet and a third air outlet, the first air outlet is connected to the second air inlet, the third air outlet is connected to the outside, and the output end of the first silo is connected to the first feed port and the second feed port respectively; the heating component comprises a heat exchanger and a first fan, the input end of the heat exchanger is connected to the second air outlet, and the input end of the heat exchanger is also connected to the The air is connected to the outside, the output end of the heat exchanger is connected to the first fan, the first fan is connected to the first air inlet, a first sampling port is provided above the first drying tank, the first sampling port is used to sample the silica gel material in the first drying tank, a second sampling port is provided above the second drying tank, the second sampling port is used to sample the silica gel material in the second drying tank; the pneumatic conveying tank includes a third feed port, a third discharge port and a fourth air outlet, the third feed port is connected to the first discharge port and the second discharge port, and the fourth air outlet is connected to the outside; the input end of the second silo is connected to the third discharge port, and the second silo is used to cool the dried silica gel material; the vibrating screen is connected to the output end of the second silo; the color sorter is connected to the vibrating screen; the third silo is connected to the color sorter, and the third silo is used to hold the cooled silica gel material.

[0008] In some embodiments, a valve assembly is also included, which includes a feed valve group, a discharge valve group, an air intake valve, an exhaust valve and a return air valve. The feed valve group includes a first feed valve and a second feed valve, the first feed valve is arranged at the first feed port, and the second feed valve is arranged at the second feed port; the discharge valve group includes a first discharge valve and a second discharge valve, the first discharge valve is arranged at the first discharge port, and the second discharge valve is arranged at the second discharge port; the air intake valve is arranged between the first fan and the first air intake; the exhaust valve is arranged at the third air outlet; and the return air valve is arranged between the second air outlet and the heat exchanger.

[0009] In some embodiments, the input end of the heat exchanger is also connected to steam, and the heat exchanger is also provided with a water outlet for discharging condensed water.

[0010] In some embodiments, the valve assembly further includes a condensate valve and a steam regulating valve. The condensate valve is arranged at the water outlet of the heat exchanger; and the steam regulating valve is arranged at the connection between the heat exchanger and the steam.

[0011] In some embodiments, it also includes a first conveying pipeline and an air supply valve. The first conveying pipeline is connected to the first discharge port and the second discharge port. One end of the first conveying pipeline is connected to the third feed port, and the other end of the first conveying pipeline is provided with an air supply port. The air supply valve is arranged on the first conveying pipeline and at the air supply port.

[0012] In some embodiments, a second fan and a filter bag are also included. The second fan is connected to the fourth air outlet of the pneumatic conveying tank; the filter bag is connected to the output end of the second fan, and the filter bag is used to filter out air impurities.

[0013] In some embodiments, a stainless steel filter is provided inside the pneumatic conveying tank, and the mesh size of the stainless steel filter is in the range of 80 to 100 meshes.

[0014] In some embodiments, the first drying tank has a conical bottom structure, a first drying interlayer is provided in the first drying tank, a first orifice plate filter layer is provided on the first drying interlayer, and the pore size range of the first orifice plate filter layer is 0.5 to 1.5 mm; and / or, the second drying tank has a conical bottom structure, a second drying interlayer is provided in the second drying tank, a second orifice plate filter layer is provided on the second drying interlayer, and the pore size range of the second orifice plate filter layer is 0.5 to 1.5 mm.

[0015] In some embodiments, it also includes a thermometer group, a level meter group and a control unit, the thermometer group includes a first thermometer and a second thermometer, the first thermometer is arranged in the first drying tank, and the second thermometer is arranged in the second drying tank; the level meter group includes a first level meter and a second level meter, the first level meter is arranged in the first drying tank, and the second level meter is arranged in the second drying tank; the control unit is electrically connected to the thermometer group, the level meter group, the valve assembly, the heating assembly, the pneumatic conveying tank, the vibrating screen and the color sorter.

[0016] In a second aspect, the present invention further provides a drying treatment method for secondary drying of silica gel, which is applicable to the drying system described in the first aspect, and the method comprises:

[0017] Put the silica gel material into the first silo;

[0018] Control the silica gel material in the first silo to be transported to the first drying tank and the second drying tank respectively;

[0019] Turn on the heat exchanger and the first fan to convert the air into hot air, which is then fed into the first drying tank and the second drying tank in sequence. Control the second air outlet to open so that the air in the second drying tank circulates into the heat exchanger for heating.

[0020] Control the temperature in the first drying tank and the second drying tank to 100-160°C until the moisture content in the silica gel material reaches the target moisture requirement;

[0021] Open the third air outlet to discharge exhaust gas;

[0022] Turn on the first fan to deliver air to the first drying tank and the second drying tank, so that the temperature in the first drying tank and the second drying tank is set to 80-100°C, and turn off the first fan to cool the silica gel material in the first drying tank and the second drying tank;

[0023] Open the first discharge port and the second discharge port, and control the pneumatic conveying tank to start, transport the silica gel material from the first drying tank and the second drying tank to the second silo, then from the second silo to the vibrating screen, then from the vibrating screen to the color sorter, and finally from the color sorter to the third silo to obtain low-moisture silica gel material.

[0024] By adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art:

[0025] The present technical solution provides a drying system and processing method for secondary drying of silica gel. The drying system includes a first silo, a drying tank group, a heating component, a pneumatic conveying tank, a second silo, a vibrating screen, a color sorter and a third silo. When in use, silica gel material is put into the first silo; the silica gel material in the first silo is controlled to be transported to the first drying tank and the second drying tank respectively; the heat exchanger and the first fan are turned on to convert the air into hot air and then input it into the first drying tank and the second drying tank in turn; the second air outlet is controlled to be opened so that the air in the second drying tank is circulated to the heat exchanger for heating; the temperature in the first drying tank and the second drying tank is controlled to be set at 100-160 ℃, until the moisture content of the silica gel material reaches the target moisture requirement; open the third air outlet to discharge the exhaust gas; turn on the first fan to transport air to the first drying tank and the second drying tank, so that the temperature in the first drying tank and the second drying tank is set at 80-100℃, and turn off the first fan to cool the silica gel material in the first drying tank and the second drying tank; open the first discharge port and the second discharge port, and control the start of the pneumatic conveying tank to transport the silica gel material from the first drying tank and the second drying tank to the second silo, and then transport it from the second silo to the vibrating screen, and then transport it from the vibrating screen to the color sorter, and then transport it from the color sorter to the third silo to obtain low-moisture silica gel material. The technical solution is to set up a drying tank group, which includes a first drying tank and a second drying tank. The first drying tank and the second drying tank are connected to the second air inlet through a first air outlet, and a second air outlet is set in the second drying tank to circulate the hot air to the heat exchanger, thereby realizing the recycling of hot air, reducing the exhaust volume, and improving the utilization rate of hot air. At the same time, the heat exchange temperature of the heat exchanger can be set according to actual needs. It can be used for drying low-moisture silica gel particles with a moisture content of 5 to 30% as raw materials, can achieve uniform product moisture, reduce silica gel surface wear, improve product appearance integrity, controllable product quality, and low investment cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 It is a flow chart of the drying system;

[0028] Figure 2 is a schematic diagram of the drying system;

[0029] Figure 3 is a schematic diagram of the first drying tank;

[0030] Figure 4 Schematic diagram of the first drying interlayer.

[0031] Reference numerals:

[0032] 1. The first silo;

[0033] 2. Drying tank group;

[0034] 21. First drying tank;

[0035] 211, first air inlet;

[0036] 212, first air outlet;

[0037] 213, first feed port;

[0038] 214, first discharge port;

[0039] 215, first drying interlayer;

[0040] 216, first orifice plate filter layer;

[0041] 22. Second drying tank;

[0042] 3. Heating component;

[0043] 31. Heat exchanger;

[0044] 32. First fan;

[0045] 4. Pneumatic conveying tank;

[0046] 41. Second fan;

[0047] 42. Filter bag;

[0048] 43. First delivery pipeline;

[0049] 5. Second silo;

[0050] 6. Vibrating screen;

[0051] 7. Color sorter;

[0052] 8. The third silo;

[0053] 901, first feed valve;

[0054] 902, second feed valve;

[0055] 903, first discharge valve;

[0056] 904, second discharge valve;

[0057] 905, air inlet valve;

[0058] 906, exhaust valve;

[0059] 907, steam regulating valve;

[0060] 908, condensate valve;

[0061] 909, air supply valve;

[0062] 910. Return air valve. DETAILED DESCRIPTION

[0063] The present invention will be described in further detail below with reference to the accompanying drawings and examples. It is particularly noted that the following examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention. Similarly, the following examples are only some embodiments of the present invention and are not intended to be exhaustive. All other embodiments obtained by those of ordinary skill in the art without creative effort are intended to fall within the scope of protection of the present invention.

[0064] See also Figure 1 and Figure 2In the first aspect, the present embodiment provides a low-moisture silica gel drying system, comprising a first silo 1, a drying tank group 2, a heating component 3, a pneumatic conveying tank 4, a second silo 5, a vibrating screen 6, a color sorter 7 and a third silo 8. The first silo 1 contains silica gel material; the drying tank group 2 comprises a first drying tank 21 and a second drying tank 22. The first drying tank 21 has a first feed port 213, a first discharge port 214, a first air inlet 211 and a first air outlet 212. The second drying tank 22 has a second feed port, a second discharge port, a second air inlet, a second air outlet and a third air outlet. The first air outlet 212 is connected to the second air inlet, and the third air outlet is connected to the outside. The output end of the first silo 1 is connected to the first feed port 213 and the second feed port respectively; the heating component 3 comprises a heat exchanger 31 and a first fan 32. The input end of the heat exchanger 31 is connected to the second air outlet. The input end of 31 is also connected to the external air, the output end of the heat exchanger 31 is connected to the first fan 32, the first fan 32 is connected to the first air inlet 211, a first sampling port is provided above the first drying tank 21, the first sampling port is used to sample the silica gel material in the first drying tank 21, a second sampling port is provided above the second drying tank 22, the second sampling port is used to sample the silica gel material in the second drying tank 22; the pneumatic conveying tank 4 includes a third feed port, a third discharge port and a fourth air outlet, the third feed port is connected to the first discharge port 214 and the second discharge port, and the fourth air outlet is connected to the outside; the input end of the second silo 5 is connected to the third discharge port, and the second silo 5 is used to cool the dried silica gel material; the vibrating screen 6 is connected to the output end of the second silo 5; the color sorter 7 is connected to the vibrating screen 6; the third silo 8 is connected to the color sorter 7, and the third silo 8 is used to hold the cooled silica gel material.

[0065] In this embodiment, the first silo 1 is used to hold silica gel material, which can be silica gel particles. It should be noted that silica gel particles with a water content of 5% to 30% are preferably used. That is, the drying system shown in this embodiment can perform secondary drying on silica gel particles with a water content of 5% to 30% to further reduce the water content in the silica gel particles and obtain low-moisture silica gel.

[0066] In this embodiment, the drying tank group 2 includes a first drying tank 21 and a second drying tank 22. It is understandable that the drying tank group 2 may also include a third drying tank and a fourth drying tank. The specific number of drying tanks can be set according to actual needs. Among them, the first drying tank 21 has a first air inlet 211 and a first air outlet 212, and the second drying tank 22 has a second air inlet and a second air outlet. The first air inlet 211 is connected to the air outlet of the first fan 32 of the heating component 3, the first air outlet 212 is connected to the second air inlet, and the second air outlet is connected to the input end of the heat exchanger 31 of the heating component 3. When a third drying tank is present, the second air outlet is connected to the third drying tank, and so on. The second drying tank 22 is also provided with a third air outlet, which is used to discharge the exhaust gas from the first drying tank 21 and the second drying tank 22 during the drying process. That is, the first drying tank 21 and the second drying tank 22 are connected in series to realize the recycling of hot air. The hot air heated by the first fan 32 first enters the first drying tank 21, then enters the second drying tank 22, and finally returns to the heat exchanger 31 for heat exchange, and is then transported to the first drying tank 21 through the first fan 32, and the cycle repeats.

[0067] It should be noted that during this process, hot air enters the first drying tank 21 to dry the silica gel particles, removing moisture from the silica gel particles, causing them to form water vapor entrained in the hot air. The water vapor then enters the second drying tank 22 to dry the silica gel particles in the second drying tank 22. A third air outlet is provided in the second drying tank 22, where the water content in the hot air is the highest. This third air outlet is opened to discharge the moist air in the second drying tank 22, thereby drying the silica gel particles.

[0068] Furthermore, in this embodiment, a first sampling port is provided above the first drying tank 21, through which the silica gel particles in the first drying tank 21 can be sampled and the moisture content of the silica gel particles can be detected. By sampling multiple times at regular intervals, the moisture content of the silica gel particles in the first drying tank 21 can be monitored. Once the moisture content of the silica gel particles meets the target moisture requirement, the first discharge port 214 is opened to transport the silica gel particles to the next device. Similarly, a second sampling port is provided above the second drying tank 22, through which the silica gel particles in the second drying tank 22 can be sampled. Once the moisture content of the silica gel particles meets the target moisture requirement, the second discharge port is opened to transport the silica gel particles to the next device.

[0069] In this embodiment, the first feed port 213 and the second feed port are connected to the first silo 1 respectively, and the silica gel material in the first silo 1 can enter the first drying tank 21 and the second drying tank 22 separately for drying operation.

[0070] In this embodiment, the heating assembly 3 includes a heat exchanger 31 and a first fan 32. The first fan 32 can be a centrifugal fan or an industrial hot air blower, capable of secondary heating the air. The heat exchanger 31 can be a finned heat exchanger 31. Specifically, the heat exchanger 31 includes a first heat exchange port and a second heat exchange port. The first heat exchange port is used to pass the gas to be heated, and the second heat exchange port is used to pass high-temperature liquid or high-temperature gas. Through structural heat exchange, the temperature of the high-temperature gas or high-temperature liquid is transferred to the gas to be heated, heating the gas to be heated. After forming hot gas, it is transported to the first drying tank 21 through the first fan 32. In this embodiment, the first heat exchange port is connected to the outside air and the second air outlet. The second heat exchange port can be connected to the high-temperature liquid, or, as described later, the second heat exchange port can be used to pass steam.

[0071] This embodiment also includes a pneumatic conveying tank 4, which is a device that transports silica gel material from one location to another via airflow. It uses gas (typically air) as a transmission medium to transport solid, powdered, or granular materials from one location to another via a pipeline or pipeline network. In this embodiment, the pneumatic conveying tank 4 is connected to the first discharge port 214 and the second discharge port. After drying, the silica gel material in the first drying tank 21 and the second drying tank 22 enters the pneumatic conveying tank 4 through the first discharge port 214 and the second discharge port. The pneumatic conveying tank 4 then transports the silica gel material to the second silo 5, the vibrating screen 6, the color sorter 7, and the third silo 8.

[0072] In this embodiment, the second silo 5 serves as a cooling silo. After cooling to room temperature in the second silo 5, the silica gel material enters the vibrating screen 6. Vibrating screen 6, through the action of vibration and the screen mesh, feeds the silica gel material onto the sieve surface, separating silica gel particles of varying sizes and moisture contents. Silicone material that meets moisture requirements is screened and passed to a color sorter 7. The color sorter 7 can be used to sort silica gel materials of different colors. Silicone materials with varying moisture contents exhibit different levels of photosensitivity. Using optical sensors and image processing technology, the color sorter 7 can quickly and accurately detect and separate silica gel materials that do not meet color requirements, thereby improving product quality and reducing waste. The screened silica gel material is then conveyed to the third silo 8, which serves as the finished product silo, specifically for storing qualified silica gel material.

[0073] In some preferred embodiments, the first feed port 213 and the first discharge port 214 are arranged relative to each other along a first direction, and the first air inlet 211 and the first air outlet 212 are arranged relative to each other along a second direction, which is opposite to the first direction. Figure 2As shown, when the first material inlet 213 and the first material outlet 214 are arranged from top to bottom, the first air inlet 211 and the first air outlet 212 are arranged from bottom to top. The bidirectional countercurrent arrangement can improve the heat exchange rate and make rational use of the characteristic of hot air flowing from bottom to top due to temperature reasons, so that the drying effect of the silica gel material in the first drying tank 21 is more thorough.

[0074] Similarly, the second material inlet and the second material outlet are arranged relative to each other along the first direction, and the second air inlet and the second air outlet are arranged relative to each other along the second direction, which is opposite to the first direction. Figure 2 As shown, when the second material inlet and the second material outlet are arranged from top to bottom, the second air inlet and the second air outlet are arranged from bottom to top. This bidirectional countercurrent arrangement can improve the heat exchange rate and rationally utilize the characteristic of hot air flowing from bottom to top due to temperature, thereby achieving a more thorough drying effect on the silica gel material in the second drying tank 22. In some embodiments, the third air outlet is provided with an exhaust valve 906 described below.

[0075] In this embodiment, a drying tank group 2 is provided, and the drying tank group 2 includes a first drying tank 21 and a second drying tank 22. The first drying tank 21 and the second drying tank 22 are connected to the second air inlet through the first air outlet 212, and a second air outlet is provided in the second drying tank 22 to circulate the hot air to the heat exchanger 31, thereby realizing the recycling of the hot air, reducing the exhaust volume, and improving the utilization rate of the hot air. At the same time, the heat exchange temperature of the heat exchanger 31 and the exhaust volume of the tail valve 906 of the third air outlet can be set according to actual needs. It can be used for drying silica gel particles with a moisture content of 5 to 30% as raw materials, can achieve uniform product moisture, reduce silica gel surface wear, improve product appearance integrity, controllable product quality, and low investment cost.

[0076] See also Figure 2 In some embodiments, a valve assembly is further included, which includes a feed valve group, a discharge valve group, an air intake valve 905, an exhaust valve 906 and a return air valve 910. The feed valve group includes a first feed valve 901 and a second feed valve 902, the first feed valve 901 is arranged at the first feed port 213, and the second feed valve 902 is arranged at the second feed port; the discharge valve group includes a first discharge valve 903 and a second discharge valve 904, the first discharge valve 903 is arranged at the first discharge port 214, and the second discharge valve 904 is arranged at the second discharge port; the air intake valve 905 is arranged between the first fan 32 and the first air intake 211; the exhaust valve 906 is arranged at the third air outlet; the return air valve 910 is arranged between the second air outlet and the heat exchanger 31.

[0077] The specific product and model of the valve assembly can be set according to actual needs. By setting up the valve assembly, the degree of automation of the entire drying system in terms of feeding, discharging, air inlet and outlet can be improved. Optionally, the drying temperature and drying time can be adjusted according to the moisture content of the silicone material before drying, achieving high drying efficiency and fast drying time. Through process chain control, automated production can be achieved.

[0078] See also Figure 2 In some embodiments, the input end of the heat exchanger 31 is also connected to steam, and a water outlet is provided on the heat exchanger 31, which is used to discharge condensed water. In this embodiment, the input end of the heat exchanger 31 is connected to steam, that is, the second heat exchange port of the heat exchanger 31 is connected to steam, which is used to transfer the heat in the steam to the gas to be heated. Furthermore, during the drying process, the water vapor in the silica gel material will be entrained in the hot air. Based on this, a water outlet is provided in the heat exchanger 31. When the hot air encounters the gas introduced from the outside, the temperature will be reduced. Alternatively, when the hot air needs to be cooled, condensed water will be generated on the inner wall of the heat exchanger 31. The water outlet can discharge the condensed water in the heat exchanger 31 to reduce the initial water content of the hot air in the subsequent drying step and improve the drying efficiency.

[0079] In some optional embodiments, steam can be obtained by transporting steam generated in the aforementioned production line of silica gel to achieve the recycling of heat energy and reduce production costs.

[0080] For further information, see Figure 2 In some embodiments, the valve assembly further includes a condensate valve 908 and a steam control valve 907. The condensate valve 908 is disposed at the water outlet of the heat exchanger 31; the steam control valve 907 is disposed at the connection between the heat exchanger 31 and the steam. In this embodiment, the steam control valve 907 is capable of regulating the flow of steam entering the heat exchanger 31 to control the heat exchange temperature of the heat exchanger 31. A temperature sensor may be disposed within the heat exchanger 31 and interlocked with the steam control valve. The first fan 32 may also be equipped with a timer start / stop device. The condensate valve 908 is capable of controlling the opening and closing of the water outlet to ensure the internal sealing of the heat exchanger 31 and reduce heat loss during the heat exchange process.

[0081] See also Figure 2 In some embodiments, it also includes a first conveying pipeline 43 and an air supply valve 909. The first conveying pipeline 43 is connected to the first discharge port 214 and the second discharge port. One end of the first conveying pipeline 43 is connected to the third feed port, and the other end of the first conveying pipeline 43 is provided with an air supply port; the air supply valve 909 is arranged on the first conveying pipeline 43 and at the air supply port.

[0082] In this embodiment, an air supply port is provided on the first conveying pipeline 43, and an air pump may also be provided at the air supply port. The air pump can timely replenish external air into the first conveying pipeline 43. It should be noted that the transportation function of the pneumatic conveying tank 4 requires sufficient air to be provided in the first conveying pipeline 43 to ensure that the silicone material can be conveyed under the influence of the air flow. Based on this, an air supply port is provided in the first conveying pipeline 43, and an air supply valve 909 is provided at the air supply port. The air supply valve 909 can adjust the air volume entering the first conveying pipeline 43 from the air supply port to ensure normal transportation of the silicone material.

[0083] See also Figure 2 In some embodiments, the system further includes a second fan 41 and a filter bag 42. The second fan 41 is connected to the fourth air outlet of the pneumatic conveying tank 4. The filter bag 42 is connected to the output end of the second fan 41 and is used to filter out air impurities. In this embodiment, the second fan 41 is disposed at the fourth air outlet of the pneumatic conveying tank 4. Excess air from the pneumatic conveying tank 4 during the conveying process can be extracted by the second fan 41 and enter the filter bag 42. The filter bag 42 can filter impurities and residual silica gel material in the excess air, ultimately forming waste gas for discharge.

[0084] In some embodiments, a stainless steel filter is provided inside the pneumatic conveying tank 4, and the mesh size of the stainless steel filter is in the range of 80 to 100 meshes. The stainless steel filter can intercept and sink the silica gel particles with high specific gravity, and the fine powder or air with light specific gravity forms a negative pressure airflow under the action of the second fan 41 and is transported forward.

[0085] See also Figure 3 and Figure 4 In some embodiments, the first drying tank 21 has a conical bottom structure, a first drying interlayer 215 is provided within the first drying tank 21, a first perforated plate filter layer 216 is provided above the first drying interlayer 215, and the size of the first perforated plate filter layer 216 ranges from 0.5 to 1.5 mm; and / or, the second drying tank 22 has a conical bottom structure, a second drying interlayer is provided within the second drying tank 22, a second perforated plate filter layer is provided above the second drying interlayer, and the size of the second perforated plate filter layer ranges from 0.5 to 1.5 mm. The perforated plate filter layer supports and retains the silica gel particles while allowing air or hot air to pass freely during the drying process. The air carries moisture, allowing the silica gel to be dried to a low moisture content.

[0086] In some embodiments, it also includes a thermometer group, a level meter group and a control unit, the thermometer group includes a first thermometer and a second thermometer, the first thermometer is arranged in the first drying tank 21, and the second thermometer is arranged in the second drying tank 22; the level meter group includes a first level meter and a second level meter, the first level meter is arranged in the first drying tank 21, and the second level meter is arranged in the second drying tank 22; the control unit is electrically connected to the thermometer group, the level meter group, the valve assembly, the heating assembly 3, the pneumatic conveying tank 4, the vibrating screen 6 and the color sorter 7.

[0087] In this embodiment, the first thermometer is used to detect the temperature within the first drying tank 21, and the second thermometer is used to detect the temperature within the second drying tank 22. A level meter is an instrument used to measure and monitor the height or level of materials in a container, storage tank, or pipeline. In this embodiment, the level meter is used to detect the level of the silica gel material. Specifically, the level meter group includes a first level meter and a second level meter. The first level meter is disposed in the first drying tank 21, and the second level meter is disposed in the second drying tank 22. The arrangement of the first and second level meters enables monitoring of the silica gel material levels within the first and second drying tanks 21, 22.

[0088] In this embodiment, a control unit is also provided, which can be equipped with a DCS control program to achieve automatic control of the valve assembly. The silicone material in the first drying tank 21 and the second drying tank 22 can be monitored through the thermometer group and the level meter group.

[0089] In a second aspect, this embodiment further provides a drying method for secondary drying of silica gel, which is applicable to the drying system described in the first aspect, and the method comprises:

[0090] Put the silica gel material into the first silo 1;

[0091] Control the silica gel material in the first silo 1 to be transported to the first drying tank 21 and the second drying tank 22 respectively;

[0092] Turn on the heat exchanger 31 and the first fan 32 to convert the air into hot air and then input it into the first drying tank 21 and the second drying tank 22 in sequence. Control the second air outlet to open so that the air in the second drying tank 22 circulates to the heat exchanger 31 for heating.

[0093] The temperature in the first drying tank 21 and the second drying tank 22 is controlled to be between 100°C and 160°C until the moisture content in the silica gel material reaches the target moisture requirement;

[0094] Open the third air outlet to discharge exhaust gas;

[0095] Turn on the first fan 32 to deliver air to the first drying tank 21 and the second drying tank 22, so that the temperature in the first drying tank 21 and the second drying tank 22 is set to 80-100°C, and then turn off the first fan 32 to cool the silica gel material in the first drying tank 21 and the second drying tank 22;

[0096] Open the first discharge port 214 and the second discharge port, and control the pneumatic conveying tank 4 to start, and transport the silica gel material from the first drying tank 21 and the second drying tank 22 to the second silo 5, and then transport it from the second silo 5 to the vibrating screen 6, and then transport it from the vibrating screen 6 to the color sorter 7, and then transport it from the color sorter 7 to the third silo 8 to obtain low-moisture silica gel material.

[0097] It should be noted that for a fixed amount of silica gel material filled with silica gel raw materials with a fixed moisture content, the drying operation can be carried out after pre-setting the drying temperature and drying time. The drying temperature and drying time can be set according to the actual application method. In this embodiment, the target moisture requirement can be set according to the customer's moisture requirements for the silica gel product.

[0098] Specifically, the method steps shown in this embodiment include:

[0099] (1) Feeding: First, put the silica gel material into the first silo 1, open the first feed valve 901 and the second feed valve 902, discharge an appropriate amount of silica gel particles into the first drying tank 21 and the second drying tank 22, and then close the first feed valve 901 and the second feed valve 902;

[0100] (2) Preheating and drying: After the feeding is completed, the steam regulating valve 907, the air inlet valve 905, and the return air valve 910 are opened, and the first fan 32 is turned on to pump the hot air to the first drying tank 21 and the second drying tank 22 in sequence. Under the action of the circulating air, the drying temperature of the silica gel material in the first drying tank 21 and the second drying tank 22 is increased to 100-160°C, and then the tail gas valve 906 of the third air outlet of the second drying tank 22 is opened. The tail gas valve 906 is used to dehumidify the dry tail gas, carrying the moisture discharged from the drying of the silica gel particles, and circulates and dries until the moisture content of the silica gel reaches the target requirement; it should be noted that the tail gas valve 906 can be opened according to actual needs during the drying stage and the cooling stage to discharge the moisture entrained by the silica gel material during the drying process.

[0101] (3) Cooling: After drying, close the steam regulating valve 907 and use circulating air to cool the silica gel material to between 80 and 100° C. without heating. After reaching the temperature, turn off the first fan 32;

[0102] (4) Discharging: After cooling, open the first discharge valve 903, the second discharge valve 904 and the air supply valve 909, and turn on the second fan 41 to transport the silica gel material in the drying tank to the pneumatic conveying tank 4 under negative pressure.

[0103] (5) Post-processing: After the discharge is completed, close the first discharge valve 903 and the second discharge valve 904, and then transfer the silica gel material in the pneumatic conveying tank 4 to the second silo 5, the vibrating screen 6, the color sorter 7, and the third silo 8 in sequence to obtain low-moisture silica gel.

[0104] The present technical solution provides a drying system and processing method for secondary drying of silica gel, the drying system includes a first silo 1, a drying tank group 2, a heating component 3, a pneumatic conveying tank 4, a second silo 5, a vibrating screen 6, a color sorter 7 and a third silo 8; when in use, silica gel material is put into the first silo 1; the silica gel material in the first silo 1 is controlled to be transported to the first drying tank 21 and the second drying tank 22 respectively; the heat exchanger 31 and the first fan 32 are turned on, the air is converted into hot air and then input into the first drying tank 21 and the second drying tank 22 in turn, the second air outlet is controlled to be opened, so that the air in the second drying tank 22 is circulated to the heat exchanger 31 for heating; the temperature in the first drying tank 21 and the second drying tank 22 is controlled to be set at 100-160°C until the silica gel is heated. The moisture content in the material reaches the target moisture requirement; the third air outlet is opened to discharge the exhaust gas; the first fan 32 is turned on to transport air to the first drying tank 21 and the second drying tank 22, so that the temperature in the first drying tank 21 and the second drying tank 22 is set at 80-100°C, and the first fan 32 is turned off to cool the silica gel material in the first drying tank 21 and the second drying tank 22; the first discharge port 214 and the second discharge port are opened, the opening of the air supply valve 909 is adjusted, and the pneumatic conveying tank 4 is controlled to start, and the silica gel material is transported from the first drying tank 21 and the second drying tank 22 to the second silo 5, and then from the second silo 5 to the vibrating screen 6, and then from the vibrating screen 6 to the color sorter 7, and then from the color sorter 7 to the third silo 8 to obtain low-moisture silica gel material. The present technical solution is provided with a drying tank group 2, which includes a first drying tank 21 and a second drying tank 22. The first drying tank 21 and the second drying tank 22 are connected to the second air inlet through the first air outlet 212, and a second air outlet is provided in the second drying tank 22 to circulate the hot air to the heat exchanger 31, thereby realizing the recycling of hot air and improving the utilization rate of hot air. At the same time, the heat exchange temperature of the heat exchanger 31 and the exhaust volume of the tail valve 906 of the third air outlet can be set according to actual needs. It can be used for drying low-moisture silica gel particles as raw materials and can achieve uniform product moisture. For example, compared with a high water content silica gel material of 78% to 82%, the present technical solution can reduce the water content in the 78% to 82% silica gel material to 5% to 30%, thereby realizing secondary drying of the silica gel material. At the same time, it reduces the surface wear of the silica gel, improves the appearance integrity of the product, and has controllable product quality and low investment cost. The above technical solution can realize automated production by setting up a control unit, realize automatic control and adjustment of various parameters in the silica gel drying process, and significantly improve the degree of automation of the entire process.

[0105] The above descriptions are only some embodiments of the present invention and do not limit the scope of protection of the present invention. Any equivalent device or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A drying system for secondary drying of silica gel, characterized in that: include: a first silo containing silica gel material; A drying tank group includes a first drying tank and a second drying tank, the first drying tank having a first feed port, a first discharge port, a first air inlet and a first air outlet, the second drying tank having a second feed port, a second discharge port, a second air inlet, a second air outlet and a third air outlet, the first air outlet is connected to the second air inlet, the third air outlet is connected to the outside, the output end of the first silo is connected to the first feed port and the second feed port, respectively, a first sampling port is provided above the first drying tank, the first sampling port is used to sample the silica gel material in the first drying tank, and a second sampling port is provided above the second drying tank, the second sampling port is used to sample the silica gel material in the second drying tank; A heating assembly comprising a heat exchanger and a first fan, wherein an input end of the heat exchanger is connected to the second air outlet, an input end of the heat exchanger is also connected to external air, an output end of the heat exchanger is connected to the first fan, and the first fan is connected to the first air inlet; A pneumatic conveying tank comprising a third feed port, a third discharge port and a fourth air outlet, wherein the third feed port is connected to the first discharge port and the second discharge port, and the fourth air outlet is connected to the outside; a second silo, wherein the input end of the second silo is connected to the third discharge port, and the second silo is used to cool the dried silica gel material; a vibrating screen connected to the output end of the second silo; a color sorter connected to the vibrating screen; The third silo is connected to the color sorter and is used to hold the cooled silica gel material.

2. The drying system for secondary drying of silica gel according to claim 1, characterized in that: Also included is a valve assembly, the valve assembly comprising: A feed valve assembly includes a first feed valve and a second feed valve, wherein the first feed valve is arranged at the first feed port, and the second feed valve is arranged at the second feed port; a discharge valve assembly, comprising a first discharge valve and a second discharge valve, wherein the first discharge valve is arranged at the first discharge port, and the second discharge valve is arranged at the second discharge port; an air inlet valve, disposed between the first fan and the first air inlet; an exhaust valve, arranged at the third air outlet; The return air valve is arranged between the second air outlet and the heat exchanger.

3. The drying system for secondary drying of silica gel according to claim 2, characterized in that: The input end of the heat exchanger is also connected to steam, and the heat exchanger is also provided with a water outlet, which is used to discharge condensed water.

4. The drying system for secondary drying of silica gel according to claim 3, characterized in that: The valve assembly further comprises: a condensate valve, arranged at the water outlet of the heat exchanger; The steam regulating valve is arranged at the connection between the heat exchanger and the steam.

5. The drying system for secondary drying of silica gel according to claim 4, characterized in that: Also includes: A first conveying pipeline is connected to the first discharge port and the second discharge port, one end of the first conveying pipeline is connected to the third feed port, and the other end of the first conveying pipeline is provided with an air supply port; The air supply valve is arranged on the first conveying pipeline and at the air supply port.

6. The drying system for secondary drying of silica gel according to claim 5, characterized in that: Also includes: a second fan connected to the fourth air outlet of the pneumatic conveying tank; A filter bag is connected to the output end of the second fan, and the filter bag is used to filter out air impurities.

7. The drying system for secondary drying of silica gel according to claim 6, characterized in that: A stainless steel filter screen is provided inside the pneumatic conveying tank, and the mesh number of the stainless steel filter screen ranges from 80 to 100 meshes.

8. The drying system for secondary drying of silica gel according to claim 7, characterized in that: The first drying tank has a conical bottom structure, a first drying interlayer is provided in the first drying tank, a first orifice plate filter layer is provided on the first drying interlayer, and the pore size of the first orifice plate filter layer ranges from 0.5 to 1.5 mm; And / or, the second drying tank has a conical bottom structure, a second drying interlayer is provided in the second drying tank, a second orifice plate filter layer is provided on the second drying interlayer, and the pore size of the second orifice plate filter layer ranges from 0.5 to 1.5 mm.

9. The drying system for secondary drying of silica gel according to claim 8, characterized in that: Also includes: a thermometer set, comprising a first thermometer and a second thermometer, wherein the first thermometer is disposed in the first drying tank, and the second thermometer is disposed in the second drying tank; A material level meter group, comprising a first material level meter and a second material level meter, wherein the first material level meter is arranged in the first drying tank, and the second material level meter is arranged in the second drying tank; The control unit is electrically connected to the thermometer group, the material level meter group, the valve assembly, the heating assembly, the pneumatic conveying tank, the vibrating screen and the color sorter.

10. A method for secondary drying of silica gel, characterized in that: Applicable to the drying system according to any one of claims 1 to 9, the method comprising: Put the silica gel material into the first silo; Control the silica gel material in the first silo to be transported to the first drying tank and the second drying tank respectively; Turn on the heat exchanger and the first fan to convert the air into hot air, which is then fed into the first drying tank and the second drying tank in sequence. Control the second air outlet to open so that the air in the second drying tank circulates into the heat exchanger for heating. Controlling the temperature in the first drying tank and the second drying tank to 100-160° C. until the moisture content in the silica gel material reaches the target moisture requirement; Open the third air outlet to discharge exhaust gas; Turning on the first fan to deliver air to the first drying tank and the second drying tank so that the temperature inside the first drying tank and the second drying tank is set to 80-100° C., and then turning off the first fan to cool the silica gel material in the first drying tank and the second drying tank; The first discharge port and the second discharge port are opened, and the pneumatic conveying tank is controlled to start, so as to transport the silica gel material from the first drying tank and the second drying tank to the second silo, and then from the second silo to the vibrating screen, and then from the vibrating screen to the color sorter, and then from the color sorter to the third silo to obtain low-moisture silica gel material.

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