Equipment, control system and control method for producing expandable graphite

Abstract

The present invention is applicable to the field of expandable graphite production, and provides a device, control system and control method for producing expandable graphite, comprising a drying device base, a cover and a micro-induction stirring component arranged inside the two; a heating chamber is arranged on the side wall of the drying device base; a ventilation outlet is arranged on the cover; the micro-induction stirring component comprises a transmission bin arranged on the cover, a driver connected to the transmission bin, a stirring shaft extending outward from the transmission bin and at least one induction lever, thereby, the present invention can adjust the stirring speed of the stirring shaft according to the expansion degree feedback of the expandable graphite, avoid the concentration of hot spots, and realize uniform heating, and at the same time, a built-in emergency cooling system can be used, if the temperature inside the equipment is too high, cooling intervention can be performed to reduce material loss.

Description

Technical Field

[0001] The invention relates to the field of expandable graphite production equipment, and in particular to equipment, a control system and a control method for producing expandable graphite. Background Art

[0002] Expandable graphite is a special graphite material that can expand rapidly when exposed to high temperatures after special chemical or physical processing to form a worm-like porous structure. This expansion process is usually accompanied by the decomposition of graphite interlayer compounds, which generates thrust to push the graphite layers apart, thereby achieving a significant increase in volume. Expandable graphite is usually used in flame retardant materials due to its excellent high temperature resistance (it can withstand high temperatures without losing its structural properties). The expansion temperature of expandable graphite is divided into high-temperature expandable graphite (expanding temperature is generally between 900°C and 1000°C) and low-temperature expandable graphite (starting expansion temperature is 110°C~150°C) due to different processing procedures.

[0003] The difference between the above two treatment processes is only that the reactants of the intercalation treatment are different, that is, both of them are subjected to acidification intercalation treatment-neutral treatment-drying treatment to obtain expandable graphite.

[0004] Among them, since the starting temperature of low-temperature expandable graphite is close to the drying temperature (drying temperature is between 80℃ and 100℃), during the drying process at this stage, operators need to pay attention to the material status at all times to avoid material temperature concentration and expansion (expandable graphite expands into expanded graphite).

[0005] In summary, the prior art obviously has inconveniences and defects in practical use, so it is necessary to improve it. Summary of the invention

[0006] In view of the above-mentioned defects, the object of the present invention is to provide an equipment, control system and control method for producing expandable graphite, which can adjust the stirring speed of the stirring shaft according to the expansion degree feedback of the expandable graphite, avoid the concentration of hot spots, and achieve uniform heating. At the same time, a built-in emergency cooling system can be used. If the temperature inside the equipment is too high, cooling intervention can be performed to reduce material loss.

[0007] In order to achieve the above-mentioned purpose, the present invention provides an equipment for producing expandable graphite, comprising a drying equipment base with an opening, a cover covering the opening and a micro-induction stirring assembly arranged inside the two; the side wall of the drying equipment base is provided with a heating chamber for heating the inner cavity; the cover is provided with a ventilation outlet; the micro-induction stirring assembly comprises a transmission bin arranged in the cover, a driver connected to the transmission bin, a stirring shaft extending outward from the transmission bin and at least one sensing lever; the end of the sensing lever has a predetermined height from the bottom of the inner cavity, which is recorded as a first state; when the sensing lever is subjected to a top force, it will swing upward by a predetermined angle, which is recorded as a second state; when the sensing lever is in the first state, the rotation speed of the stirring shaft is a first rotation speed; when the sensing lever is in the second state, the rotation speed of the stirring shaft is a second rotation speed; the value of the second rotation speed is higher than the value of the first rotation speed.

[0008] According to the device for producing expandable graphite of the present invention, a ventilation inlet is also provided on the cover, which is connected to the low-temperature airflow supply device, and a control valve is installed on the pipeline connecting the two; when the sensing lever is in the first state, the control valve of the ventilation inlet is closed; when the sensing lever is in the second state, the control valve of the ventilation inlet is opened.

[0009] According to the apparatus for producing expandable graphite of the present invention, the stirring shaft is arranged vertically.

[0010] According to the device for producing expandable graphite of the present invention, the base of the drying device is a rotating body structure, and the axis of the stirring shaft coincides with the rotation axis of the base of the drying device.

[0011] According to the equipment for producing expandable graphite of the present invention, spiral stirring blades are arranged on the periphery of the stirring shaft, and the rotating stirring shaft lifts the material upward.

[0012] According to the equipment for producing expandable graphite of the present invention, the transmission bin includes a transmission bin housing fixed to the cover, a first guide ring fixedly connected to the transmission bin housing, and a second guide ring rotatably installed in the transmission bin housing and fixed to the stirring shaft; a plurality of switching members are arranged at equal intervals in the second guide ring and the first guide ring; a support disk is arranged at the center of the plurality of switching members to support and drive them to rotate, and is connected to the output shaft of the driver; the switching member is a rotating body structure with an arc as the directrix, and is externally fitted with the inner edge of the second guide ring and internally fitted with the outer circumferential surface of the support disk; the switching member is connected to the sensing lever; when the angle of the sensing lever changes, the angle of the rotation axis of the driving switching member changes to change the position of the cross-sectional circle contacted by the second guide ring, the support disk and the switching member.

[0013] According to the device for producing expandable graphite of the present invention, a connector is rotatably mounted on the end of the rotation axis of the switching member; the end of the induction lever is hinged to the connector, and the middle predetermined position is movably hinged to the first guide ring.

[0014] According to the device for producing expandable graphite of the present invention, the switching member is a spherical structure, and four of them are arranged in a circle.

[0015] According to the device for producing expandable graphite of the present invention, the heating chamber is heated by steam; a heating port and an exhaust port are arranged on the side wall of the heating chamber; and the heating port is connected to an air supply device for supplying hot air flow.

[0016] The control system of the production equipment according to the present invention comprises an expansion degree detection unit arranged on the side wall of the base of the drying equipment, which comprises a sensor for detecting the material height h in the inner cavity and a general control unit connected to the sensor: the general control unit is connected to the control unit of the driver and the control unit of the control valve; an expansion warning height H1 is arranged inside the general control unit according to the material addition amount planning; during the drying process, if the height h of the material detected by the sensor is higher than the expansion warning height H1, the general control unit drives the control valve to open; the general control unit has an expansion warning rate S1 inside, and during the drying process, if the sensor cooperates with the general control unit to calculate that the puffing rate s of the material is higher than the expansion warning rate S1, the general control unit drives the control valve to open.

[0017] According to the control system of the present invention, the expansion warning height H1 is calculated according to the following formula: H1=H0×α; wherein H0 is the material height of the expandable graphite before drying; and α is the height warning coefficient.

[0018] According to the control system of the present invention, the expansion rate s is calculated according to the following formula: s=(H2-H0)÷T; H2 is the expansion height of the material after drying time T.

[0019] The control method adopted by the control system of the present invention includes: S1: adding materials into the equipment; after the addition is completed, starting the equipment to enter the drying operation; S2: the sensing lever adjusts the rotation speed of the stirring shaft in real time according to the expansion height of the material; S3: when the expansion height h of the material is higher than the expansion warning height H1 or the puffing rate s of the material is higher than the expansion warning rate S1, the control valve is opened and the low-temperature airflow enters the interior of the equipment.

[0020] According to the control method of the present invention, when the control valve is opened, the heating chamber stops heating synchronously.

[0021] According to the control method of the present invention, after the cooling operation of the equipment is completed, the expanded expanded graphite is screened out.

[0022] The invention provides a device for producing expandable graphite, comprising a drying device base with an opening, a cover covering the opening, and a micro-induction stirring assembly arranged inside the two; a heating chamber for heating an inner cavity is arranged on the side wall of the drying device base; a ventilation outlet is arranged on the cover; the micro-induction stirring assembly comprises a transmission bin arranged on the cover, a driver connected to the transmission bin, a stirring shaft extending outward from the transmission bin, and at least one induction lever; the end of the induction lever has a predetermined height from the bottom of the inner cavity, which is recorded as a first state; when the induction lever is subjected to a top force, it will swing upward by a predetermined angle, which is recorded as a second state; when the induction lever is in the first state, the rotation speed of the stirring shaft is a first rotation speed; when the induction lever is in the second state, the rotation speed of the stirring shaft is a second rotation speed; the value of the second rotation speed is higher than the value of the first rotation speed, the invention can adjust the stirring speed of the stirring shaft according to the expansion degree feedback of the expandable graphite, avoid the concentration of hot spots, and realize uniform heating, and at the same time, a built-in emergency cooling system can be used, and if the temperature inside the equipment is too high, cooling intervention can be performed to reduce material loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of the external structure of the present invention;

[0024] Figure 2 It is a schematic diagram of the internal structure of the present invention;

[0025] Figure 3 It is a three-dimensional structural schematic diagram of the micro-induction stirring assembly of the present invention without the transmission chamber housing;

[0026] Figure 4 yes Figure 3 Schematic diagram of the adjustment of the medium and micro induction stirring assembly;

[0027] Figure 5 It is a schematic diagram of signal connection of each unit of the control system;

[0028] Figure 6 It is a step diagram of the control method;

[0029] In the figure, 1-drying equipment base, 11-heating chamber, 111-heating port, 112-exhaust port, 12-inner cavity, 2-cover, 21-ventilation outlet, 22-ventilation inlet, 3-transmission bin, 31-transmission bin housing, 32-first guide ring, 33-second guide ring, 34-switching part, 35-support plate, 4-stirring shaft, 5-sensing lever, 6-connector, 7-driver. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0031] See also Figure 1 and Figure 2 The present invention provides an apparatus, a control system and a control method for producing expandable graphite, wherein the apparatus for producing expandable graphite comprises a drying apparatus base 1 having an opening, a sealing cover 2 covering the opening and a micro-induction stirring assembly arranged inside the two.

[0032] A heating chamber 11 for heating the inner cavity 12 is arranged in the side wall of the drying equipment base 1; a heating unit is arranged inside the heating chamber 11, and the heating method adopted is not unique (electric heating, liquid heat exchange heating, gas heat exchange heating, etc. can be adopted). Specifically in the present embodiment, the heating unit adopts steam heating (gas heat exchange heating); specifically, a heating port 111 and an exhaust port 112 are arranged on the side wall of the heating chamber 11; the heating port 111 is connected to an air supply device for supplying hot air flow, and the exhaust port 112 is connected to the outside atmosphere or other waste heat recovery equipment (it is an existing structure, and this application only briefly describes it). During the heating process, the air supply device supplies hot air (generally steam) to the heating chamber 11, and the hot air exchanges heat with the side wall of the heating chamber 11 (the heat passes through the side wall of the heating chamber 11 into the inner cavity 12), and the hot air that loses heat is discharged from the exhaust port 112.

[0033] Preferably, a ventilation outlet 21 is provided on the sealing cover 2; the ventilation outlet 21 is used to adjust the air pressure in the inner cavity 12 to prevent the air pressure in the inner cavity 12 from being too high or too low.

[0034] See also Figure 2 , Figure 3 and Figure 4 The micro-inductive stirring assembly includes a transmission chamber 3 disposed on the cover 2, a driver 7 connected to the transmission chamber 3, a stirring shaft 4 extending outward from the transmission chamber 3, and at least one inductive lever 5;

[0035] In this embodiment, the stirring shaft 4 is vertically arranged and driven by the driver 7, and the structure may not be unique, that is, a stirring shaft 4 of various structural types may be used for stirring. Specifically in this embodiment (select one), the stirring shaft 4 is provided with spiral stirring blades on its periphery. At the same time, the axis of the stirring shaft 4 coincides with the axis of rotation of the drying equipment base 1 (the drying equipment base 1 is a rotating body structure). When stirring, the rotating stirring shaft 4 (driven by the driver 7, the specific connection is described in detail below) drives the stirring blades to rotate, and the material near the middle of the inner cavity 12 is lifted to the upper layer, while the material near the side wall of the inner cavity 12 enters the vicinity of the middle for replenishment, thereby forming a cycle ( Figure 2 as indicated by the arrow).

[0036] The end of the sensing lever 5 is at a predetermined height from the bottom of the inner cavity 12, which is recorded as the first state; at this time, the equipment is in the early stage of drying, the material in the inner cavity 12 has a large water content, and the rotation speed of the stirring shaft 4 is the first speed (about 80~125r / min); the stirring shaft 4 at this speed slowly stirs the material to make it evenly heated, thereby improving the drying efficiency.

[0037] When the induction lever 5 is subjected to the top force, it will swing upward to a predetermined angle, which is recorded as the second state; the top force is generated by part of the expandable graphite. At this time, the equipment is in the late stage of drying. The induction lever 5 is mainly used to detect the expansion degree of the expandable graphite. Since the drying temperature is very close to the expansion starting temperature of the low-temperature expandable graphite, if there is uneven heat transfer in the inner cavity 12, the expandable graphite in the local area will expand (expand into expandable graphite). At this time, it means that the water content of the material in the inner cavity 12 is low, and the stirring speed of the stirring shaft 4 needs to be increased. Then the rotation speed of the stirring shaft 4 is the second speed; the value of the second speed is higher than the value of the first speed. At this speed, the stirring shaft 4 enters a high-speed rotation state, which, on the one hand, further ensures the uniformity of the material being heated, and on the other hand, dissipates heat and cools the material through high-speed stirring.

[0038] The stirring shaft 4 is driven by the induction lever 5 to switch the speed. The transmission chamber 3 connecting the two comprises a transmission chamber housing 31 fixedly connected to the cover 2, a first guide ring 32 fixedly connected to the transmission chamber housing 31, and a second guide ring 33 rotatably installed in the transmission chamber housing 31 and fixedly connected to the stirring shaft 4; both the first guide ring 32 and the second guide ring 33 are annular structures.

[0039] A plurality of switching elements 34 are provided at equal intervals in the second guide loop 33 and the first guide loop 32 ; the number of the switching elements 34 is the same as the number of the sensing levers 5 .

[0040] A support plate 35 is provided at the center of the multiple switching members 34 to support and drive them to rotate, and is connected to the output shaft of the driver 7; the switching member 34 is a rotating body structure with an arc as the reference line (specifically in this embodiment, in order to ensure the transmission stability of the mechanism in the transmission bin 3, the switching member 34 is a spherical structure, and at least four of them are provided), and is externally in contact with the inner edge of the second guide ring 33 and internally in contact with the outer peripheral surface of the support plate 35.

[0041] See also Figure 4 , the switching member 34 is connected to the sensing lever 5; when the angle of the sensing lever 5 changes, it will drive the rotation axis of the switching member 34 to change its angle, and further change the cross-sectional circle position where the second guide ring 33, the support plate 35 and the switching member 34 are in contact. Specifically, a connector 6 is rotatably mounted on the end of the rotation axis of the switching member 34; the end of the sensing lever 5 is hinged to the connector 6 (the two adopt a movable hinge structure, and the end of the sensing lever 5 is provided with a moving groove for the movement of the hinge shaft of the connector 6. When the angle of the rotation axis of the switching member 34 changes, the hinge shaft of the connector 6 moves and adjusts in the moving groove to ensure the normal operation of the angle switching of the switching member 34), and the predetermined position in the middle is hinged to the first guide ring 32 ( Figure 3 and Figure 4 as shown).

[0042] When the sensing lever 5 swings upward and the rotation axis of the driving switching member 34 changes its angle, the cross-sectional circular position of the switching member 34 contacted by the second guide ring 33 moves from point A (close to the rotation axis position) to point B (close to the center equator position). On the contrary, the cross-sectional circular position of the switching member 34 contacted by the support plate 35 moves from close to the center equator position to close to the rotation axis position. The change in the meshing point between the two further leads to a change in the transmission ratio, thereby increasing the rotation speed of the second guide ring 33.

[0043] With the above structure, on the one hand, the induction lever 5 is used as a switching drive component, and the switching sensitivity is better. At the same time, an inorganic speed change switching method is adopted, so the stirring shaft 4 has no stagnation state and the switching is more stable.

[0044] Preferably, the cover 2 of the present invention is also provided with a ventilation inlet 22, which is connected to a low-temperature airflow supply device (which can supply low-temperature airflow), and a control valve is installed on the pipe connecting the two; if the temperature in the inner cavity 12 is in an uncontrollable state (caused by internal or external factors of the equipment, such as human operating errors causing the heating temperature of the heating unit to be too high, or other reasons such as equipment failure), the control valve on the ventilation inlet 22 is opened, and the cooling airflow is supplied to the inner cavity 12 to quickly reduce the internal temperature to reduce the loss of materials (avoid the expansion of a large amount of expandable graphite). Of course, when the above-mentioned induction lever 5 is in the second state, the control valve on the ventilation inlet 22 can also be opened to assist in cooling (it should be noted that when the induction lever 5 is in the first state, the control valve on the ventilation inlet 22 is closed).

[0045] See also Figure 5 , for the opening control of the control valve of the ventilation inlet 22, the present application also provides a control system applied to the above production equipment, including an expansion detection unit arranged on the side wall of the base 1 of the drying equipment, which includes a sensor for detecting the height h of the material in the inner cavity 12 (a high-temperature resistant laser sensor can be used) and a master control unit connected to the sensor: the master control unit is connected to the control unit of the driver 7 and the control unit of the control valve;

[0046] The main control unit is provided with an expansion warning height H1 according to the material addition amount planning. During the drying process, the sensor detects that the material height h is higher than the expansion warning height H1. At this time, it indicates that there is a point in the inner cavity 12 where the temperature is too high, and the proportion of the expanded expanded graphite relative to the unexpanded expandable graphite is too high. The equipment needs to urgently intervene to cool the material. The main control unit drives the control valve to open, and the cooling airflow enters the inner cavity 12.

[0047] The expansion warning height H1 is calculated according to the following formula: H1=H0×α; wherein H0 is the material height of the expandable graphite before drying; and α is the height warning coefficient.

[0048] Alternatively, the master control unit has an expansion warning rate S1 inside. During the drying process, the sensor cooperates with the master control unit to calculate that the expansion rate s of the material is higher than the expansion warning rate S1. At this time, it also means that there is a point in the inner cavity 12 where the temperature is too high, and the equipment performs emergency intervention (the master control unit drives the control valve to open). The only difference is that at this time, the expandable graphite is in the expansion process (only has a tendency to expand in large quantities), and the expansion amount is small.

[0049] The expansion rate s is calculated according to the following formula: s=(H2-H0)÷T; H2 is the expansion height of the material after drying time T.

[0050] See also Figure 6 In addition, the present invention further provides a control method for the above control system, including:

[0051] S1: Add materials into the equipment; after adding, start the equipment to enter the drying operation;

[0052] S2: The sensing lever 5 adjusts the speed of the stirring shaft 4 in real time according to the expansion height of the material;

[0053] S3: When the expansion height h of the material is higher than the expansion warning height H1 or the puffing rate s of the material is higher than the expansion warning rate S1, the control valve opens and the low-temperature airflow enters the equipment.

[0054] Furthermore, when the control valve of the present invention is opened, the heating chamber 11 stops heating simultaneously.

[0055] Finally, after the cooling operation of the equipment is completed, the expanded expanded graphite needs to be screened out.

[0056] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A device for producing expandable graphite, characterized in that, It includes a drying equipment base with an opening, a sealing cover covering the opening, and a micro-induction stirring component arranged inside the two; The side wall of the drying equipment base is provided with a heating chamber for heating the inner cavity; The sealing cover is provided with a ventilation outlet; The micro-inductive stirring assembly includes a transmission chamber arranged on the cover, a driver connected to the transmission chamber, a stirring shaft extending outward from the transmission chamber, and at least one inductive lever; The end of the sensing lever is at a predetermined height from the bottom of the inner cavity, which is recorded as the first state; when the sensing lever is subjected to a top force, it will swing upward at a predetermined angle, which is recorded as the second state; The sensing lever is in a first state, and the rotation speed of the stirring shaft is a first rotation speed; The sensing lever is in the second state, and the rotation speed of the stirring shaft is a second rotation speed; the value of the second rotation speed is higher than the value of the first rotation speed; The transmission bin comprises a transmission bin housing fixedly connected to the sealing cover, a first guide ring fixedly connected to the transmission bin housing, and a second guide ring rotatably installed in the transmission bin housing and fixedly connected to the stirring shaft; A plurality of switching elements are arranged at equal intervals in the second guide loop and the first guide loop; A support disk is provided at the center of the plurality of switching members to support and drive the switching members to rotate, and is connected to the output shaft of the driver; the switching member is a rotating body structure with an arc as the criterion, and is externally in contact with the inner edge of the second guide ring and internally in contact with the outer peripheral surface of the support disk; The switching member is connected to the sensing lever; when the sensing lever changes its angle, the rotation axis of the switching member is driven to change its angle, so as to change the position of the cross-sectional circle where the second guide ring, the support plate and the switching member are in contact.

2. The device for producing expandable graphite according to claim 1, characterized in that The cover is also provided with a ventilation inlet, which is connected to the low-temperature air flow supply device, and a control valve is installed on the pipeline connecting the two; The sensing lever is in the first state, and the control valve of the ventilation inlet is closed; The sensing lever is in the second state, and the control valve of the ventilation inlet is opened.

3. The device for producing expandable graphite according to claim 1 or 2, characterized in that The stirring shaft is arranged vertically.

4. The apparatus for producing expandable graphite according to claim 3, characterized in that The drying equipment base is a rotating body structure, and the axis of the stirring shaft coincides with the rotation axis of the drying equipment base.

5. The apparatus for producing expandable graphite according to claim 4, characterized in that The outer periphery of the stirring shaft is provided with spiral stirring blades, and the stirring shaft lifts the material upward after rotating.

6. The apparatus for producing expandable graphite according to claim 1, characterized in that The switching member is a spherical structure, and four switching members are arranged in a circle.

7. The apparatus for producing expandable graphite according to claim 1, characterized in that A connector is rotatably mounted on the end of the rotation axis of the switching member; The end of the sensing lever is hinged to the connecting head, and the middle predetermined position is movably hinged to the first guide loop.

8. The apparatus for producing expandable graphite according to claim 1, characterized in that The heating chamber is heated by steam; A heating port and an exhaust port are arranged on the side wall of the heating chamber; the heating port is connected to an air supply device for supplying hot air flow.

9. A control system applied to the equipment for producing expandable graphite according to claim 2, characterized in that: It includes an expansion detection unit arranged on the side wall of the drying device base, which includes a sensor for detecting the height h of the material in the inner cavity and a master control unit connected to the sensor: the master control unit is connected to the control unit of the driver and the control unit of the control valve; The main control unit is internally provided with an expansion warning height H1 according to the material addition amount planning; during the drying process, if the sensor detects that the material height h is higher than the expansion warning height H1, the main control unit drives the control valve to open; The main control unit has an expansion warning rate S1 inside. During the drying process, if the sensor cooperates with the main control unit to calculate that the expansion rate s of the material is higher than the expansion warning rate S1, the main control unit drives the control valve to open; The expansion warning height H1 is calculated according to the following formula: H1=H0×α; H0 is the material height of expandable graphite before drying; α is the height warning coefficient; The puffing rate s is calculated according to the following formula: s=(H2-H0)÷T; H2 is the expansion height of the material after drying time T.

10. A control method adopted by the control system according to claim 9, characterized in that: include: S1: Add materials into the production equipment; after adding, start the equipment to enter the drying operation; S2: The induction lever adjusts the stirring shaft speed in real time according to the expansion height of the material; S3: When the expansion height h of the material is higher than the expansion warning height H1 or the puffing rate s of the material is higher than the expansion warning rate S1, the control valve opens and the low-temperature airflow enters the equipment.

11. The control method according to claim 10, characterized in that: When the control valve is opened, the heating chamber stops heating synchronously.

12. The control method according to claim 10 or 11, characterized in that: After the cooling operation of the production equipment is completed, the expanded expanded graphite is screened out.

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