RU2408829C1 - Device for drying high-moisture content materials - Google Patents

Abstract

FIELD: chemistry. ^ SUBSTANCE: device for drying high-moisture content materials has a drying chamber with an infrared radiator connected to a vacuum pumping line. The vacuum pumping line is fitted with adsorbers. The infrared radiator is mounted on the inner surface of the cover. Inputs of adsorbers are connected to outputs of neighbouring adsorbers. There is a trough in the bottom part of the tray, where the said trough is connected by connecting pieces to the vacuum pumping line and the tray is connected to a neutral gas supply line. ^ EFFECT: device increases efficiency. ^ 6 cl, 11 dwg

Description

The invention relates to a device for drying high-moisture materials, in particular peroxide compounds of alkali and alkaline earth metals.

A device for drying high-moisture materials according to ed. USSR N 1513352, IPC F26B 3/30, 1989. The device includes a drying chamber in which a tray for the material to be dried is installed, infrared emitters are placed in the upper and lower panels of the chamber. The chamber is equipped with a device for supplying a drying agent and a device for mixing it. Drying of the product in such a device is carried out in two stages with the regulation of the radiation intensity.

A disadvantage of the known device is the inability to stabilize the temperature in the drying volume due to the inability to supply heat to the material to be dried from the side of the pallet.

A device for drying high-moisture materials is also known, including a drying chamber in which a mesh tray with a material to be dried is installed, an infrared emitter placed on the upper wall of the chamber, and a drying agent supply system. The side walls of the drying chamber, as well as the baking tray-reflector installed under the pallet, have a mirror-reflective surface. In the drying chamber, a temperature sensor is mounted above the pallet with the material, connected to the automatic control unit, and the automatic control unit is connected to the critical heating temperature setpoint. Drying of the material in such a device is carried out by irradiation with direct and reflected infrared rays, while the drying process is regulated by adjusting the temperature mode by switching infrared emitters accordingly and changing the distance between the tray and infrared emitters. The switching of infrared emitters is carried out when the temperature critical for a particular material is reached. Such a constructive implementation of the device allows to reduce the energy intensity of the drying process by using the reflection of infrared rays (RF patent No. 2163992, IPC 7 F26B 3/30, 3/28, 2001).

However, the known device does not allow to create a uniform temperature field in the mass of the dried material, since the movement of infrared emitters occurs only in the vertical plane and from a common drive. In addition, when drying highly moist and thermally unstable chemical products, such as peroxide compounds of alkali and alkaline earth metals, the known device cannot provide the necessary rate of moisture removal due to imperfection of heating systems and removal of released water vapor.

Closest to the invention is a device for drying high-moisture materials according to the patent of Russian Federation No. 2293264, IPC 7 F26B 3/30, 3/2, 2007. The device comprises a drying chamber made in the form of a tray and a lid, and an infrared emitter. The pallet and infrared emitter are mounted on the frame on opposite sides of a cover of optically transparent material fixed to the frame and can be moved relative to it. A heat exchanger is installed in the drip tray. The pallet is mounted rotatably with respect to the lid and is connected to a vacuum line and a neutral gas supply line. Profiling plates are installed on the heat exchanger, and it is connected to the circulation pump. A refrigerator is installed between the heat exchanger and the pump inlet, and a heater is installed between the pump outlet and the heat exchanger.

However, the known device does not provide sufficient drying performance, since in this design it is impossible to provide the required rate of removal of water vapor from the drying chamber and to prevent the dispersion of infrared radiation, and hence the heat flux into the surrounding space. At the same time, the heating intensity of the dried material is significantly reduced.

The objective of the invention is to increase the efficiency of the drying process.

The technical result of the invention is to increase the productivity of a device for drying high-moisture materials.

The technical result is achieved by the fact that in the device for drying high-moisture materials, including a drying chamber, consisting of a tray and a lid, an infrared emitter and a vacuum line connected to the drying chamber, an infrared emitter is mounted on a reflector mounted on the inner surface of the lid, in the vacuum line installed adsorbers, and cooling jackets are installed on the outer surfaces of the tray and lid of the drying chamber.

In the lower part of the pallet there is a chute connected by fittings to the evacuation line, and the pallet is connected to the neutral gas supply line.

The adsorbers are equipped with heaters and are connected to the hot air supply line.

The lid of the drying chamber is pivotally mounted on a pallet and provided with a counterweight.

The cooling shirts are connected to the atmosphere and an automatic water discharge system in the form of a drain funnel.

Infrared emitters are equipped with temperature meters and are connected to the power source through voltage regulators.

The installation of adsorbers in the vacuum line, the installation of infrared emitters on a reflector mounted on the inner surface of the lid, and the installation of cooling jackets on the external surfaces of the pallet and lid of the drying chamber provide increased productivity due to:

- intensive absorption of water vapor by the adsorber. Since the pumping speed with a conventional vacuum pump is dozens of times less productive than the rate of absorption of water vapor by an adsorber, the role of a vacuum pump is to create a vacuum in the drying chamber at which water vapor diffuses into the adsorbers at a higher speed;

- reducing the scattering of infrared radiation, and consequently, the heat flux into the surrounding space through the use of a reflector;

- achieving more efficient heating of the dried material, since at the beginning of drying the dried product is optically transparent, this ensures the heating of the material to the entire thickness;

- selective absorption of infrared radiation by water vapor;

- reducing the duration of heating and cooling of the drying chamber and the material being dried.

Placement in the lower part of the pallet of the gutter, connected by fittings to the vacuum line, and the connection of the pallet with the neutral gas supply line provide an increase in the pumping speed.

The supply of heaters to the adsorbers and their connection to the hot air supply line reduce the duration of adsorbent regeneration.

Fastening the lid of the drying chamber pivotally on the pallet and supplying it with a counterweight provide the convenience of opening the drying chamber when loading the dried product and unloading it after the drying process.

The connection of the cooling jackets of the lid and the pallet of the drying chamber with the atmosphere and the automatic water discharge system in the form of a drain funnel ensures that there are no water in the cooling jackets after the drying process is completed, which eliminates heat loss during heating of the water during drying.

The supply of infrared emitters with temperature meters and their connection to the power source through voltage regulators provide a metered supply of heat to the dried product, which is especially important when drying materials that decompose when overheated.

The drawings show the design of the device, where:

figure 1 - schematic diagram of the installation;

figure 2 - General view of the drying chamber in the working position, cross section;

figure 3 - tray drying chamber (section BB, figure 2);

figure 4 - drying chamber at the time of loading and unloading of material;

figure 5 is a view of the lid of the drying chamber from the inside (view along arrow A, figure 4);

6 is a front view of the installation, showing the connection of the drying chamber with adsorbers;

Fig.7 is a top view of the drying chamber tray with profiling plates removed (view along arrow B, Fig.4);

Fig.8 is the same as in Fig.7 in the working position with installed profiling plates and the material to be dried;

Fig.9 is a cross section of adsorbers;

figure 10 is a top view of the lid of the drying chamber, the position of the shut-off element when supplying cooling water (view along arrow B, figure 2);

11 is a bottom view of the drying chamber pan, the position of the shutoff member when the cooling water supply is stopped (view along arrow G, FIG. 2).

The list of positions:

1 - drying chamber;

2 (1), 2 (2), 2 (3) - adsorbers;

3 - valve;

4 - valve;

5 - vacuum pump;

6 - vacuum gauge;

7 - valve;

8 - compressor:

9 - manometer:

10 - air heater;

11 - dump valve;

12 - pipe water supply;

13 - pipe discharge water;

14 - valve inlet;

15 - manovacuum meter;

16 - pallet;

17 - trough;

18 - pipe;

19 - flange;

20 - cover;

21 - reflector;

22 - IR emitter;

23 - hinge;

24 - counterweight;

25 - profiling plate;

26 - material subjected to drying;

27 - support grid;

28 - fittings support lattice;

29 - heater;

30 - pipe;

31 - mesh wall;

32 - pipe;

33 - cooling shirt;

34 - funnel drain cooling system;

35 - three-way valve cooling system.

The device for drying high-moisture materials contains, as shown in Fig. 1, a drying chamber 1 connected to adsorbers 2 (1), 2 (2), 2 (3) through valves 3. Second nozzles of adsorbers 2 (1), 2 (2 ), 2 (3) through valves 4 with a vacuum pump 5 connected to a vacuum gauge 6. The adsorbers 2 (1), 2 (2), 2 (3) are connected through valves 7 to a compressor 8 equipped with a pressure gauge 9 and an air heater 10. Between the adsorbers 2 (1), 2 (2), 2 (3) and the drying chamber 1, vent valves 11 are installed in the ventilation line. The drying chamber 1 is connected by water supply pipes 12 to a water supply line and water discharge nozzles 13 with sewage. An inlet valve 14 and a manovacuum gauge 15 are installed on the drying chamber 1. The drying chamber 1 contains a tray 16, in the lower part of which a longitudinal recess is made in the form of a groove 17, to which pipes 18 are welded for connection with adsorbers 2 (1), 2 (2), 2 (3). A flange 19 is welded to the lateral surface of the pallet 16, on which the cover 20 is mounted, a reflector 21 is fixed inside it with the Elstein stein infrared emitters 22 of type T attached to it with built-in thermocouples equipped with temperature meters and connected to the power source via voltage regulators (not shown) . The cover 20 is fixed to the pallet 16 by means of a hinge 23 and is equipped with a counterweight 24. Inside the pallet, profiling plates 25 are installed with the material 26 to be dried. The plates 25 are placed on a support grid 27 made of pipes in the form of a flat coil, the fittings 28 of which are extended outside the pallet 16. In the adsorbers 2 (1), 2 (2), 2 (3), infrared heaters 29 are installed. Adsorbers 2 (1 ), 2 (2), 2 (3) pipes 30 are connected to the drying chamber. Mesh walls 31 are installed inside the adsorbers, between which the adsorbent is placed. To connect to the vacuum system, the adsorbers contain nozzles 32 located on opposite sides relative to the nozzles 31 of the adsorbers 2 (1), 2 (2), 2 (3). On the outer surface of the pallet 16 and the lid 20 are placed cooling jackets 33 connected to the funnels 34 of the drain part of the cooling system and three-way valves 35 for supplying water and air to the cooling system.

The device operates as follows.

The material to be dried 26 is laid on the profiling plates 25, which are placed on the support grid 27 of the drying chamber 1 in the open position (as shown in FIG. 4). The coolant through the fittings 28 can be supplied to the support grid 27, providing quick heating of the material 26 and the profiling plates 25.

The lid from spontaneous lowering is held by the counterweight 24. The drying chamber 1 is sealed by turning the lid 20 in the hinge 23 until it closes with the seal on the flange 19 of the pallet 16. By the vacuum pump 5 through valve 4, through valves 3 of one of the adsorbers 2 (1), 2 ( 2), 2 (3), nozzles 18 and the groove 17 in the drying chamber 1 creates a vacuum. Heat is applied to the material 26 to be dried by turning on infrared emitters 22 equipped with temperature meters and connected to a power source. The degree of heating is carried out through voltage regulators (not shown). Moreover, the polished surface of the reflector 21 helps to create a uniform temperature field on the surface of the material 26. In the drying process, the operability of the vacuum pump 5 is controlled by the readings of the vacuum gauge 6. Drying can be carried out in a stream of inert gas or dry decarbonized air. In this case, gas is supplied to the cavity of the drying chamber 1 through the inlet valve 14. The degree of rarefaction in this case can be controlled by the readings of the vacuum gauge 15. The degree of heating of the infrared emitters 22 can be controlled by thermocouples built into the emitters with a secondary device (not shown). After drying, the heating of infrared emitters is turned off, and water is supplied to the cooling shirts 33 through the nozzles 12 of the pallet 16 and the lid 20 through open three-way taps 35. The position of the plug of the three-way valve 35 is shown in FIG. 10. From the cooling jacket 33, water is drained through the nozzles 13 into funnels into the drain cooling systems 34. After cooling the sump 16 and cover 20, the plugs of the three-way valves 35 are transferred to the position shown in FIG. 11. In this case, the cooling jackets 33 are cut off from the water supply line, and they are connected to the atmosphere, ensuring water is drained through the nozzles 13 into the drain funnels of the cooling system 34. After cooling the drying chamber 1, the vacuum pump 5 is turned off and after closing the open valve 3, the inlet valve 14 opens. Subsequent unloading of the material 26 is carried out in the reverse order to that described above.

During the drying process, water vapor from the material 26 is intensively absorbed in the adsorber 2 (1), 2 (2), 2 (3). This is facilitated by the creation of a vacuum in the cavity of the drying chamber 1 by reducing the boiling point of moisture and increasing its diffusion rate. During operation, periodic regeneration of adsorbers is necessary, for which adsorbers 2 (1), 2 (2), 2 (3) are cut off from the drying chamber 1 by closing valves 3 and from the vacuum system by valves 4. Valves 7 and 11 open and compressor 8 and heater are turned on air 10. Hot air passes through the pipe 32, the mesh wall 31 and transfers heat to the adsorber. Humidified air passes through the second mesh wall 31 and through the pipe 30 and the discharge valve 11 is removed into the atmosphere. The operation of the compressor 8 is controlled by the readings of the pressure gauge 9. At the same time, the heaters 29 are turned on, providing heating of the adsorber. The temperature in each adsorber 2 (1), 2 (2), 2 (3) is controlled by thermal converters (not shown). After holding at a given temperature, the heaters 29, the air heater 10 and the compressor 8 are turned off and valves 7 and 11 are closed. After the adsorbers 2 (1), 2 (2), 2 (3) are cooled to room temperature, they are again suitable for operation.

Another option for the operation and regeneration of adsorbers 2 (1), 2 (2), 2 (3) is to turn them on alternately by opening the corresponding pair of valves 3 and 4. In this case, this operation scheme is possible: one adsorber absorbs moisture, the second is regenerated, as described above, and the third is cooled. After the first adsorber is saturated with moisture, the third, cooled adsorber is switched on, the first adsorber is transferred to the desorption mode, and the second to cooling mode.

The proposed device can improve the performance of the device for drying high-moisture materials.

Claims (6)

1. Device for drying high-moisture materials, including a drying chamber consisting of a tray and a lid, an infrared emitter and a vacuum line connected to the drying chamber, characterized in that the infrared emitter is mounted on a reflector mounted on the inner surface of the lid, adsorbers are installed in the vacuum line and cooling jackets are installed on the outer surfaces of the tray and the lid of the drying chamber. 2. The device for drying high-moisture materials according to claim 1, characterized in that in the lower part of the pallet there is a groove connected by fittings to the vacuum line, and the pallet is connected to the neutral gas supply line. 3. The device for drying high-moisture materials according to claim 1, characterized in that the adsorbers are equipped with heaters and connected to a hot air supply line. 4. The device for drying high-moisture materials according to claim 1, characterized in that the lid of the drying chamber is pivotally mounted on a pallet and provided with a counterweight. 5. The device for drying high-moisture materials according to claim 1, characterized in that the cooling jackets are connected to the atmosphere and an automatic water discharge system in the form of a drain funnel. 6. The device for drying high-moisture materials according to claim 1, characterized in that the infrared emitters are equipped with temperature meters and are connected to a power source through voltage regulators.

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