Fluidized bed suitable for silicon dioxide dehydration

Abstract

A fluidized bed suitable for silicon dioxide dehydration, comprising a cylinder body (2), an upper sealing head (3) provided on the top of the cylinder body (2), a gas distribution conical plate (5) and a lower sealing head (6) provided on the bottom of the cylinder body (2), and a discharge tube (7) and a discharge valve (8) provided on the lower sealing head (6). A discharge port (9) is formed on the bottom of the gas distribution conical plate (5). The discharge valve (8) comprises: a lifting / lowering valve rod (801), a conical valve core (802) provided at the top end of the valve rod (801) and in separable contact with the discharge port (9), and a pneumatic elastic jacking mechanism transmittingly connected to the valve rod (801).

Description

A fluidized bed suitable for dehydration of silicon dioxide Technical Field

[0001] The utility model belongs to the technical field of fluidized dehydration and relates to a fluidized bed suitable for dehydrating silicon dioxide. Background Art

[0002] In the polyethylene carrier catalyst configuration industry, the fluidized bed used for silica dehydration is an essential key equipment. Its ultimate goal is to remove water molecules from silica. During the dehydration process, the carrier silica gel needs to remove water evenly within a certain unit time. Completing the dehydration process too quickly or too slowly will cause the silica gel to break and the skeleton pores to collapse.

[0003] During the silica gel filling stage, the traditional unloading intermediate tank is used to introduce the silica gel into the fluidized bed for silica dehydration, which often results in unclean silica gel unloading due to static electricity or secondary contamination, and the silica gel may stick to the wall and form powder bridges.

[0004] During the dehydration process, due to the difference in the quality of the silica gel, the fluidized surging state is out of control, and a large amount of ultrafine powder quickly escapes from the inside of the filter, causing great waste and post-processing burden, and often clogging the filter.

[0005] During the dehydration process, the furnace body expands due to heat, causing the gap between the furnace body and the discharge bottom valve to increase, resulting in a large amount of silica gel leaking from the discharge bottom valve, which not only causes environmental pollution, but also causes a large amount of finished products to become hazardous waste.

[0006] During the activation stage, the outer shell of the electric heater heats the furnace core, while the internal fluidized nitrogen is at room temperature before entering the furnace core, which has a cooling effect. While wasting energy, it also has a rapid cooling effect on the silica gel, affecting the quality of the product.

[0007] Utility Model Content

[0008] The purpose of the utility model is to provide a fluidized bed suitable for dehydrating silicon dioxide, which is used to solve the problem that a gap is generated between a discharge valve and a discharge port due to temperature changes in the furnace, thereby making the seal unreliable.

[0009] The purpose of the utility model can be achieved through the following technical solutions:

[0010] A fluidized bed suitable for dehydrating silicon dioxide comprises a cylinder, an upper head arranged at the top of the cylinder, a gas distribution cone plate and a lower head arranged at the bottom of the cylinder, and a discharge pipe and a discharge valve arranged on the lower head. A discharge port is provided at the bottom of the gas distribution cone plate; the discharge valve comprises: a valve stem arranged to be raised and lowered, a conical valve core arranged at the top of the valve stem and in detachable contact with the discharge port, and a pneumatic elastic lifting mechanism connected to the valve stem.

[0011] Furthermore, the pneumatic elastic lifting mechanism includes a shell provided with an inner cavity, a pneumatic diaphragm that divides the inner cavity into upper and lower chambers, a support spring arranged between the bottom side of the pneumatic diaphragm and the bottom side of the lower chamber, and an air pressure regulator for increasing or decreasing the pressure of the upper chamber, and the valve stem is connected to the pneumatic diaphragm.

[0012] In the sealed state, the support spring elastically lifts the pneumatic diaphragm, making the conical valve core tightly connected to the discharge port. When the furnace temperature changes, the discharge port and the conical valve core deform to varying degrees, thereby generating a gap between the two. Due to the elastic lifting force of the support spring, the conical valve core rises as the feed port expands, and the conical structure of the valve core is further utilized to maintain a tight connection with the discharge port to avoid leakage.

[0013] As a preferred technical solution, a support plate is provided on the bottom side of the pneumatic diaphragm, the valve stem is connected to the support plate, and the top end of the support spring abuts against the support plate.

[0014] Furthermore, the lower chamber is provided with an air pressure regulator for increasing or decreasing the pressure.

[0015] During discharge, pressure is applied to the upper chamber, causing the pneumatic diaphragm to dent, thereby moving the valve stem downward and allowing the tapered valve core to exit the discharge port. At this point, the lower chamber is depressurized to assist in the diaphragm's dent. Conversely, to seal the discharge port, the upper chamber is depressurized and / or the lower chamber is pressurized, causing the pneumatic diaphragm to convex, lifting the valve stem.

[0016] Furthermore, the pneumatic elastic lifting mechanism is arranged outside the lower head, and the valve stem passes through the side wall of the discharge pipe and is transmission-connected to the pneumatic elastic lifting mechanism;

[0017] A sealing filler is provided between the valve stem and the side wall of the discharge pipe.

[0018] As an optimal technical solution, a valve stem mounting tube is provided on the side wall of the discharge pipe, the valve stem passes through the valve stem mounting tube, a sealing filler groove is opened on the inner wall of the valve stem mounting tube, and a sealing filler is filled between the sealing filler groove and the valve stem.

[0019] As a preferred technical solution, a packing gland is further provided at the lower end of the valve stem mounting tube.

[0020] As a preferred technical solution, a hollow column is provided between the lower end of the valve stem mounting tube and the shell, and the valve stem passes through the column and is connected to the upper wall of the shell and the pneumatic film.

[0021] Furthermore, a cooling air duct is provided on the outer cover of the lower portion of the cylinder, a cooling air inlet and a cooling air outlet are provided on the cooling air duct, and the cooling air inlet is also connected to the cooling fan.

[0022] Furthermore, the fluidized bed also includes a feed port provided on the cylinder and a vacuum pump connected to the cylinder.

[0023] Furthermore, the gas distribution cone plate has a cone plate structure of 50-70 degrees.

[0024] As a preferred technical solution, the gas distribution cone plate has a 60° cone plate structure.

[0025] Furthermore, the gas distribution cone plate is provided with a plurality of gas distribution holes perpendicular to the cone plate.

[0026] Furthermore, the gas distribution holes have a pore diameter of 1-1.5 mm.

[0027] As a preferred technical solution, the diameter of the gas distribution holes is 1.2 mm.

[0028] Furthermore, the discharge pipe is provided with an air inlet pipe connected to an air source, and the air inlet pipe is provided with a pipeline preheater.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1) The utility model uses a pneumatic elastic lifting mechanism, specifically a spring and a pneumatic diaphragm, to maintain the lifting effect on the conical valve core and the valve stem. Therefore, when the furnace temperature changes and a gap is generated between the conical valve core and the discharge port, the valve core and the discharge port can be kept sealed, so that there is no leakage even when the temperature changes.

[0031] 2) The utility model realizes a dilute phase feeding mode of sucking silica gel through a feed port connected to the barrel and a vacuum pump. When silica gel enters the furnace, it does not enter rapidly and in large quantities. The ultrafine powder can be discharged through the filter element in an orderly manner per unit time, and the filter element will not be blocked by a rapid and large influx of silica gel.

[0032] 3) The fluidized nitrogen entering the furnace of the utility model is preheated by the pipeline preheater. When removing physical water in the early stage of activation, it is only necessary to use the pipeline preheater device to preheat the nitrogen to the specified temperature according to the time point. The nitrogen can directly act on the silica gel evenly, making the fluidization state more stable and saving energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG1 is a schematic structural diagram of a fluidized bed suitable for dehydration of silicon dioxide in an embodiment;

[0034] Figure 2 is a schematic diagram of the structure of the gas distribution cone plate;

[0035] Figure 3 is a schematic structural diagram of a filter plate;

[0036] Figure 4 is a schematic structural diagram of a discharge valve;

[0037] FIG5 is a schematic structural diagram of a fluidized bed system suitable for dehydration of silicon dioxide in an embodiment;

[0038] Description of the marks in the figure:

[0039] 1-support, 2-cylinder, 3-upper head, 4-filter plate, 5-gas distribution cone plate, 6-lower head, 7-discharge pipe, 8-discharge valve, 801-valve stem, 802-conical valve core, 803-shell, 804-pneumatic diaphragm, 805-support spring, 806-sealing packing, 807-packing gland, 808-column, 9-discharge port, 10-pipeline preheater, 11-cooling air duct, 12-cooling air outlet, 13-cooling fan, 14-feed port. DETAILED DESCRIPTION

[0040] The following embodiments are implemented based on the above technical solution of the present invention, and provide detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following embodiments.

[0041] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not require further definition or explanation in subsequent drawings.

[0042] The following embodiments of the present invention are described in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0043] The fluidizing gas medium of the utility model is nitrogen with a content of 99.99%.

[0044] Example:

[0045] This embodiment, based on a high-performance electric heating powder dehydrator with a fluidizing device (CN202770114U), has undergone a secondary improvement, aiming to provide a more comprehensive solution to the difficulties found in the actual production process through technical means. After the improvement, the quality and production efficiency of silica gel produced by the fluidized bed for silica gel dehydration of the second generation have been greatly improved compared to the first generation. The details are as follows:

[0046] A fluidized bed suitable for dehydrating silicon dioxide comprises a support 1, a cylinder 2 arranged on the support 1, an upper head 3 and a high-temperature-resistant and high-precision filter plate 4 arranged on the top of the cylinder 2, a gas distribution cone plate 5 and a lower head 6 arranged at the bottom of the cylinder 2, a gas distribution cone plate 5 and a lower head 6 arranged at the bottom of the cylinder 2, and a discharge pipe 7 and a discharge valve 8 arranged on the lower head 6.

[0047] Among them, a discharge port 9 is provided at the bottom of the gas distribution cone plate 5;

[0048] The discharge valve is an adjustable upward expansion plunger discharge valve, which is a discharge valve specially designed for the fluidized bed. The discharge valve can withstand high temperatures of 550°C and can change with the changes in furnace temperature and the expansion of the shape. The pre-tightening force in the diaphragm always supports the seal between the valve core and the discharge port, so that the temperature changes without leakage.

[0049] Specifically, discharge valve 8 comprises a valve stem 801 that is arranged to rise and fall, a conical valve core 802 disposed at the top of valve stem 801 and in releasable contact with discharge port 9, and a pneumatic elastic lifting mechanism drivingly connected to valve stem 801. The pneumatic elastic lifting mechanism comprises a housing 803 with an inner cavity, a pneumatic diaphragm 804 that divides the inner cavity into upper and lower chambers, a support spring 805 disposed between the bottom side of pneumatic diaphragm 804 and the bottom side of the lower chamber, and a pneumatic pressure regulator for increasing or decreasing the pressure in the upper chamber. Valve stem 801 is connected to pneumatic diaphragm 804.

[0050] In the sealed state, the support spring 805 exerts an elastic lifting effect on the pneumatic film 804, so that the conical valve core 802 is tightly connected to the discharge port 9. When the furnace temperature changes and the discharge port 9 and the conical valve core 802 are deformed to varying degrees, thereby generating a gap between the two, the elastic lifting force of the support spring 805 causes the conical valve core 802 to rise as the discharge port 9 expands, and further utilizes the conical structure of the valve core to maintain a tight connection with the discharge port 9 to avoid leakage.

[0051] In some preferred embodiments, a support plate is provided on the bottom side of the pneumatic membrane 804 , the valve stem 801 is connected to the support plate, and the top end of the support spring 805 abuts against the support plate.

[0052] In some preferred embodiments, the lower chamber is provided with a corresponding air pressure regulator for increasing or decreasing the pressure.

[0053] During discharge, pressure is applied to the upper chamber, causing the pneumatic diaphragm 804 to dent, thereby driving the valve stem 801 downward and allowing the conical valve core 802 to exit the discharge port 9. At this point, the lower chamber can be depressurized to assist in the depressurization of the pneumatic diaphragm 804. Conversely, when sealing the discharge port 9 is required, the upper chamber is depressurized and / or the lower chamber is pressurized, causing the pneumatic diaphragm 804 to convex, thereby lifting the valve stem 801.

[0054] In some specific embodiments, the pneumatic elastic lifting mechanism is arranged outside the lower head 6, and the valve stem 801 passes through the side wall of the discharge pipe 7 and is transmission-connected to the pneumatic elastic lifting mechanism; a sealing filler 806 is provided between the valve stem 801 and the side wall of the discharge pipe 7.

[0055] More specifically, a valve stem mounting tube is provided on the side wall of the discharge pipe 7 , and the valve stem 801 passes through the valve stem mounting tube. A sealing packing groove is provided on the inner wall of the valve stem mounting tube, and a sealing packing 806 is filled between the sealing packing groove and the valve stem 801 .

[0056] In some specific embodiments, a packing gland 807 is further provided at the lower end of the valve stem mounting tube.

[0057] In some specific embodiments, a hollow column 808 is provided between the lower end of the valve stem mounting tube and the housing 803 , and the valve stem 801 passes through the column 808 and is connected to the upper wall of the housing 803 and the pneumatic film 804 .

[0058] In some specific embodiments, a cooling air duct 11 is provided on the outer sleeve of the lower part of the cylinder 2, and a cooling air inlet and a cooling air outlet 12 are provided on the cooling air duct 11, and the cooling air inlet is also connected to the cooling fan 13. The function of the cooling air duct is to be used when the heating furnace enters the cooling stage. After the dehydrator completes its work, it is cooled by natural cooling. The cold source comes from the cold nitrogen at the bottom, which is generally conducted to the outer shell of the heating plate through the cooling liner. Because this time takes more than ten hours, the production efficiency is reduced and a large amount of nitrogen is wasted. In this embodiment, the cooling air duct 11 is arranged between the heater and the liner at the bottom of the furnace body. When the heating wire is naturally cooled to 350°C, the fan is turned on to blow natural wind in to accelerate the cooling.

[0059] In some specific embodiments, the fluidized bed further comprises a feed port 14 provided on the barrel 2 and a vacuum pump connected to the barrel 2. Preferably, the vacuum pump is a water ring vacuum pump.

[0060] The inner shell of the cylinder can be designed to withstand a pressure of 1.0MPa and a vacuum of -0.1MPa at room temperature through its shape and structure. When the furnace body is at room temperature, the water ring vacuum pump can be turned on to extract the furnace shell into a negative pressure state. Due to the negative pressure in the furnace, the silica gel can be sucked into the furnace shell through the pipe connected to it. At the same time, under the action of the fluidizing gas, the sucked silica gel enters the furnace body and is in a surging state. At the same time, the color and impurities of the silica gel can be manually identified when extracting the silica gel. At the same time, the actual weight of the silica gel entering the fluidized bed shell can be determined by weighing the silica gel barrel before suction. The work efficiency and quality have been greatly improved compared to the previous ones, and it can effectively avoid the problems of unclean silica gel unloading, wall sticking and powder bridging caused by static electricity or secondary pollution when introducing silica gel through the unloading intermediate tank.

[0061] And because the silica gel suction method is a dilute phase conveying mode, the silica gel does not enter the furnace quickly and in large quantities. The ultrafine powder can be discharged through the filter element in an orderly manner per unit time, and the filter element will not be blocked by the rapid influx of large amounts of silica gel.

[0062] In some specific embodiments, the gas distribution conical plate 5 has a 50-70° conical plate structure. In this embodiment, the gas distribution conical plate 5 has a 60° conical plate structure. Furthermore, the gas distribution conical plate 5 is provided with a plurality of gas distribution holes perpendicular to the conical plate. The gas distribution holes have a diameter of 1-1.5 mm, and in this embodiment, the diameter of the gas distribution holes is 1.2 mm.

[0063] The cone plate is welded to the bottom of the cylinder. According to the distribution requirements, 1.2mm small holes perpendicular to the cone surface are drilled on the flat stainless steel plate by laser. Then it is cold-bent and rolled into a cone surface. The holes in the distribution plate are arranged at a certain angle, which can make the silica gel surging inside the fluidized bed controllable within the aspect ratio of the furnace.

[0064] In some specific embodiments, the discharge pipe 7 is provided with an air inlet pipe connected to an air source, and the air inlet pipe is provided with a pipeline preheater 10. The fluidized nitrogen gas entering the furnace is preheated by the pipeline preheater. When removing physical water in the early stage of activation, the pipeline preheater only needs to be used to preheat the nitrogen to a specified temperature according to the time point. This can evenly complete the nitrogen's direct action on the silica gel, making the fluidization state more stable and saving energy.

[0065] In other embodiments, the fluidized bed may further include an electric heater, a back-blowing valve group, a vent valve group, a self-operated constant pressure valve, a flow meter, and an electronic control system.

[0066] The above description of the embodiments is intended to facilitate understanding and use of the utility model by those skilled in the art. Those skilled in the art will readily be able to make various modifications to these embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the utility model is not limited to the above-described embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of this utility model without departing from the scope of this utility model should be within the scope of protection of this utility model.

Claims

1. A fluidized bed suitable for dehydrating silicon dioxide, characterized in that: The invention comprises a cylinder (2), an upper sealing head (3) arranged at the top of the cylinder (2), a gas distribution cone plate (5) and a lower sealing head (6) arranged at the bottom of the cylinder (2), and a discharge pipe (7) and a discharge valve (8) arranged on the lower sealing head (6); a discharge port (9) is arranged at the bottom of the gas distribution cone plate (5); the discharge valve (8) comprises: a valve stem (801) arranged to be lifted, a conical valve core (802) arranged at the top of the valve stem (801) and detachably contacting the discharge port (9), and a pneumatic elastic lifting mechanism drivingly connected to the valve stem (801).

2. The fluidized bed suitable for dehydrating silicon dioxide according to claim 1, characterized in that: The pneumatic elastic lifting mechanism includes a shell (803) provided with an inner cavity, a pneumatic film (804) that divides the inner cavity into upper and lower chambers, a supporting spring (805) provided between the bottom side of the pneumatic film (804) and the bottom side of the lower chamber, and a pneumatic pressure regulator for increasing or decreasing the pressure of the upper chamber, and the valve stem (801) is connected to the pneumatic film (804).

3. The fluidized bed suitable for dehydrating silicon dioxide according to claim 2, characterized in that: The lower chamber is correspondingly provided with an air pressure regulator for increasing or decreasing the pressure.

4. The fluidized bed suitable for dehydration of silicon dioxide according to claim 2, characterized in that: The pneumatic elastic lifting mechanism is arranged outside the lower sealing head (6), and the valve stem (801) passes through the side wall of the discharge pipe (7) and is transmission-connected with the pneumatic elastic lifting mechanism; A sealing filler (806) is provided between the valve stem (801) and the side wall of the discharge pipe (7).

5. The fluidized bed suitable for dehydration of silicon dioxide according to claim 1, characterized in that: A cooling air duct (11) is provided on the outer sleeve of the lower part of the cylinder (2), and a cooling air inlet and a cooling air outlet (12) are provided on the cooling air duct (11), and the cooling air inlet is also connected to a cooling fan (13).

6. The fluidized bed suitable for dehydration of silicon dioxide according to claim 1, characterized in that: It also includes a feed port (14) arranged on the barrel (2) and a vacuum pump connected to the barrel (2).

7. The fluidized bed suitable for dehydration of silicon dioxide according to claim 1, characterized in that: The gas distribution cone plate (5) is a cone plate structure with an angle of 50-70 degrees.

8. The fluidized bed suitable for dehydrating silicon dioxide according to claim 1, characterized in that: The gas distribution cone plate (5) is provided with a plurality of gas distribution holes which are perpendicular to the cone plate.

9. The fluidized bed suitable for dehydrating silicon dioxide according to claim 8, characterized in that: The diameter of the gas distribution holes is 1-1.5 mm.

10. The fluidized bed suitable for dehydration of silicon dioxide according to claim 1, characterized in that: The discharge pipe (7) is provided with an air inlet pipe connected to an air source, and the air inlet pipe is provided with a pipeline preheater (10).

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