Closed recovery system for additive feeding powder of polypropylene granulation unit

Abstract

The utility model discloses a polypropylene granulation unit additive feeding powder closed recovery system, which is characterized by comprising a breathing stock bin, an anti-static filter for filtering powder in ascending air flow is arranged in the breathing stock bin, the breathing stock bin is connected with a recovery tank through a pipeline, and the recovery tank is connected with the breathing stock bin through a pipeline. The recovery tank is communicated with an inlet line of a granulator hopper, so that recovered powder and powder fed into the granulator hopper by the system are synchronously processed and granulated; the breathing stock bin and the anti-static filter in the breathing stock bin are arranged, dust and powder brought out by rising hot airflow in the balance pipe and rising airflow of the breathing stock bin are filtered and recycled, the recycled powder is concentrated in the recycling tank, pollution can be controlled, cost and consumption can be reduced, and solid waste is reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of polypropylene processing, in particular to a closed recovery system for additive feeding powder of a polypropylene granulation unit. Background Art

[0002] In the existing polypropylene granulation process, additive powder is mixed by manual feeding, conveying with a screw pusher, electronic weighing, and mixing with polypropylene powder. Manual feeding is to cut the powder bag with a knife and then pour it into the additive feeder manually. Because the system is open, dust is everywhere, which pollutes the operating environment. When conveying polypropylene powder to the extrusion granulator, the corresponding gas and the hot air generated by the extrusion granulator will be discharged from the breathing filter along the balance pipe. The original system has a fan to force the gas to be discharged. Because the forced exhaust will form a vacuum in the system, resulting in discontinuous feeding and affecting production, the fan is stopped. Due to the poor exhaust of the filter, the bag in the filter was removed during production, so that the gas with powder was directly discharged into the atmosphere, polluting the environment. The balance pipe of the original system has one and two powder discharge ports on the third and fourth floors respectively. Plastic bags are tied to the discharge port to receive the discharged powder. Because it cannot be sealed and recycled in real time, it leads to the waste of about 5t of powder per month and causes environmental pollution.

[0003] The feeding port cannot be closed during feeding, and a local effective vacuum cannot be formed, resulting in the overflow of additive powder. The dust suction port in the feeding hopper is set too low, and the dust absorption is too large. In addition, the original filter element is cancelled, which aggravates the dust pollution; the breathing port of the breathing filter is directly discharged, resulting in some dust overflow; there is no effective means to recover the suspended powder in the balance pipe and the dust at the discharge port, resulting in a poor working environment, affecting the health of operators and the normal operation of equipment. Utility Model Content

[0004] In view of the shortcomings of the prior art, a closed recovery system for additive powder of a polypropylene granulation unit is proposed, which solves the problems in the above-mentioned background technology.

[0005] In order to achieve the above purpose, the utility model proposes the following technologies to achieve it:

[0006] A closed recovery system for additive powder of a polypropylene granulation unit comprises a breathing silo, wherein an antistatic filter for filtering powder in an ascending airflow is arranged in the breathing silo, the breathing silo is connected to a recovery tank via a pipeline, and the recovery tank is connected to an inlet line of a granulator hopper, so that the recovered powder is synchronously processed and granulated with the powder fed into the granulator hopper by the system.

[0007] Furthermore, the antistatic filter includes a filter element, and a plurality of the filter elements are provided, and the plurality of filter elements are symmetrically arranged around the central axis of the breathing silo.

[0008] Furthermore, the filter element is configured to be a hollow cylinder, the material of the filter element is polyester fiber, and an antistatic coating is provided on the surface.

[0009] Furthermore, a back-blowing assembly is arranged above the filter element, and the back-blowing assembly includes an aeration head, and the jet end of the aeration head is directed toward the filter element to spray and purge the powder filtered on the filter element.

[0010] Furthermore, the backflush assembly also includes a gas tank, a pulse valve and a pressure regulating valve. The pulse valve is arranged between the gas tank and the aeration head. The gas in the gas tank is depressurized by the pressure regulating valve and then ejected from the aeration head through the pulse valve.

[0011] Furthermore, a partition is provided in the middle of the filter element to divide the filter element into two groups, and two groups of aeration heads are provided corresponding to the filter element, and the two groups of aeration heads alternately spray air to back-blow the filter element.

[0012] Furthermore, a screw conveyor is provided between the recovery tank and the granulator hopper inlet line, the discharge end of the recovery tank is connected to the feed port of the screw conveyor, and the discharge port of the screw conveyor is connected to the granulator hopper inlet line.

[0013] Furthermore, a tuning fork level meter is provided in the recovery tank, and the tuning fork level meter is connected to the screw conveyor signal. When the powder in the recovery tank reaches a preset level, the tuning fork level meter sends a signal to control the operation of the screw conveyor to transport the powder in the recovery tank to the hopper inlet line of the granulator.

[0014] Furthermore, it also includes an auxiliary agent feeding box, the side wall of which is provided with a feeding port with a feeding door, and the feeding port is in a closed state during feeding to achieve closed feeding.

[0015] Furthermore, one side of the breathing silo is connected to an emptying port collecting tank, and the breathing silo, the emptying port collecting tank, the recovery tank and the pipeline are respectively provided with pneumatic oscillators, and the pneumatic oscillators generate vibrations to shake off the attached powder.

[0016] Compared with the prior art, the comprehensive effects brought about by the utility model include: setting a breathing silo and an anti-static filter inside it, filtering and recovering the dust and powder brought out by the rising hot air flow in the balance pipe and the rising air flow in the breathing silo, and concentrating the recovered powder in a recovery tank, which can not only control pollution but also achieve cost reduction and consumption saving and reduce the generation of solid waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the utility model;

[0018] Figure 2 This is a schematic diagram of the structure of the breathing silo in the embodiment of the utility model;

[0019] Figure 3 This is a schematic diagram of the top view of the breathing silo according to an embodiment of the utility model;

[0020] Figure 4 This is a schematic diagram of the structure of the backflush assembly of the utility model embodiment;

[0021] Figure 5 This is a schematic diagram of the filter element structure of an embodiment of the utility model.

[0022] Legend: 1. Granulator hopper inlet line; 2. Breathing silo; 3. Pipeline; 4. Recovery tank; 5. Filter element; 6. Aeration head; 7. Gas tank; 8. Partition; 9. Screw conveyor; 10. Additive feeding box; 11. Emptying port collection tank; 12. Pneumatic oscillator; 13. Connecting pipe; 14. First connecting pipe; 15. Second connecting pipe; 16. Second floor floor; 17. Third floor floor; 18. Fourth floor floor; 19. Fifth floor floor. DETAILED DESCRIPTION

[0023] The following will be combined with the accompanying drawings to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of them. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the protection scope of the utility model.

[0024] In this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. The orientation or position relationship indicated by the terms "upper", "lower", "left", "right", "top", etc. is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation to the utility model.

[0025] like Figures 1 to 5 As shown, a closed recovery system for additive powder of a polypropylene granulation unit includes a breathing silo 2, in which an antistatic filter for filtering powder in an ascending airflow is arranged, and the breathing silo 2 is connected to a recovery tank 4 via a pipeline 3, and the recovery tank 4 is connected to a granulator hopper inlet line 1, so that the recovered powder and the powder fed into the granulator hopper by the system are processed and granulated synchronously.

[0026] A breathing silo 2 and an anti-static filter inside it are provided to filter and recover the dust and powder brought out by the rising hot air flow in the balance pipe and the rising air flow in the breathing silo 2, and the recovered powder is concentrated in a recovery tank 4, which can control pollution, reduce costs and save consumption, and reduce the generation of solid waste.

[0027] Specifically, the anti-static filter is directly connected to the breathing port, and the anti-static filter adopts a conical design to prevent material accumulation. The breathing silo 2 and the recovery tank 4 are connected by a pipeline 3 and connected to the original system balance pipe, so that the powder and dust discharged from the discharge port on the original system balance pipeline are filtered and then directly recovered into the recovery tank 4 for collection, and then collected to the granulator hopper inlet line 1 and pushed into the granulator hopper, so that the recovered powder and dust are processed and granulated together with the powder sent into the granulator hopper by the system by the extrusion granulator to produce polypropylene particles.

[0028] Specifically, the recovery system of this embodiment is arranged in a multi-story building, the granulator hopper inlet line 1 passes through the second floor ground 16, the recovery tank 4 is arranged on the second floor ground 16, the pipeline 3 passes through the third floor ground 17 and the fourth floor ground 18 and is connected to the discharge port of the breathing silo 2, and the breathing silo 2 passes through the fifth floor ground 19 and extends above the fifth floor ground 19.

[0029] In the closed recovery system of the additive feeding powder of the polypropylene granulation unit of the present embodiment, the anti-static filter includes a filter element 5, and a plurality of filter elements 5 are provided. The plurality of filter elements 5 are symmetrically arranged around the central axis of the breathing silo 2. Preferably, the filter elements 5 are distributed in a square shape, and the square is tangent to the inner wall of the breathing silo 2.

[0030] The above-mentioned arrangement is used to filter the powder and dust in the rising airflow, which is arranged to be tangential to the breathing silo 2, so as to maximize the filtering and adsorption area of ​​the filter element 5. The above-mentioned arrangement changes the original bag filter into an anti-static filter, thereby increasing the filtering area and limiting the environmental pollution as much as possible. In this way, the exhaust fan can be removed to create a relatively closed space for powder transportation.

[0031] Specifically, the filter element 5 is a φ240*800 cartridge type anti-static filter element, 16 of which are provided, and the filtration area can reach 56m 2 , bearing pressure 2-2.5kpa, filtration efficiency 99%.

[0032] In the closed recovery system for additive powder of the polypropylene granulation unit of the present embodiment, the filter element 5 is configured as a hollow cylinder, the filter element 5 is made of a polyester fiber substrate, and an antistatic coating is provided on the surface.

[0033] Specifically, the cartridge-type anti-static filter element uses polyester fiber as the base material, applies an electrostatic coating on the surface, and is equipped with polyester fiber oil-proof and waterproof material. The filtration accuracy is 5μm, and the filtration accuracy for equivalent diameter dust is over 99%.

[0034] In the closed recovery system for additive powder of the polypropylene granulation unit of the present embodiment, a backflush assembly is arranged above the filter element 5, and the backflush assembly includes an aeration head 6, and the jet end of the aeration head 6 is directed toward the filter element 5 to blow the powder filtered on the filter element 5 with jet.

[0035] A back-blowing assembly is provided to blow air into the filter element 5 from a direction opposite to the rising airflow through the aeration head 6 to purge the powder attached to the filter element 5 and transport it to the recovery tank 4 through the pipeline 3 for recovery.

[0036] In the closed recovery system for additive powder of the polypropylene granulation unit of the present embodiment, the back-blowing assembly further comprises a gas tank 7, a pulse valve and a pressure regulating valve. The pulse valve is arranged between the gas tank 7 and the aeration head 6. The gas in the gas tank 7 is depressurized by the pressure regulating valve and then ejected from the aeration head 6 through the pulse valve.

[0037] Specifically, high-pressure nitrogen is stored in the gas tank 7, and the pressure regulating valve is adjusted to compress the nitrogen to quickly release the pressure and spray it from the aeration head 6. The compressed nitrogen enters the filter element 5 through the pulse valve for spraying and cleaning. The nitrogen enters the filter element 5 at a high flow rate, causing the filter element 5 to expand rapidly, causing an impact vibration, so that the dust attached to the filter element 5 is shaken off, and the fine dust adsorbed on the surface of the filter element 5 is shaken off into the breathing silo 2 under the action of the airflow. Preferably, the pulse spraying pressure is 0.4-0.6MPa, and the air supply must be kept constant during operation.

[0038] In the closed recovery system for additive powder of the polypropylene granulation unit of the present embodiment, a partition 8 is provided in the middle of the filter element 5 to divide the filter element 5 into two groups, and two groups of aeration heads 6 are provided corresponding to the filter element 5, and the two groups of aeration heads 6 alternately spray air to back-blow the filter element 5.

[0039] Two groups of filter elements 5 and aeration heads 6 are provided to prevent excessive air intake during back-blowing of the aeration head 6 and affect the normal operation of the extrusion granulator. The two groups of filter elements 5 installed in the breathing silo 2 are back-blown alternately by the aeration head 6, and a pulse valve is used to achieve timed segmented purging of the filter by the aeration head 6. The timed purging time interval, purging time and number of times are controlled by PLC.

[0040] Specifically, when the PLC signal is sent, the compressed nitrogen in the gas tank 7 is quickly depressurized and sprayed out from the aeration head 6, and the compressed nitrogen enters the filter element 5 through the pulse valve for spraying and cleaning. Each spraying and cleaning is 1S, paused for 2S, and 10 times of soot blowing, and the interval time for each group is 15 minutes. The above parameters can be changed according to the use of the filter element.

[0041] In the closed recovery system of the additive powder for the polypropylene granulation unit of the present embodiment, a screw conveyor 9 is provided between the recovery tank 4 and the granulator hopper inlet line 1, the discharge end of the recovery tank 4 is connected to the feed port of the screw conveyor 9, and the discharge port of the screw conveyor 9 is connected to the granulator hopper inlet line 1.

[0042] The spiral conveyor 9 is provided to convey the recovered powder, so that continuous conveying with high conveying efficiency can be achieved, and accumulation of powder in the recovery tank 4 can be avoided, resulting in incomplete conveying.

[0043] In the closed recovery system for additive-dosing powder of the polypropylene granulation unit of the present embodiment, a tuning fork level meter is arranged in the recovery tank 4, and the tuning fork level meter is connected with the screw conveyor 9 by signal. When the powder in the recovery tank 4 reaches a preset level, the tuning fork level meter sends a signal to control the operation of the screw conveyor 9 to transport the powder in the recovery tank 4 to the granulator hopper inlet line 1.

[0044] Specifically, in the recovery tank 4, the effective volume is 0.05m 3 A tuning fork level meter is installed at the granulator. When the powder reaches the specified level, the screw conveyor 9 starts to push the recovered powder to the granulator hopper inlet line 1.

[0045] Preferably, two tuning fork level meters are provided, and when the powder material is higher than the higher tuning fork level, the timing screw conveyor 9 is started, and when the powder material is lower than the lower tuning fork level, the timing screw conveyor 9 stops running and conveying.

[0046] The closed recovery system for additive powder in the polypropylene granulation unit of the present embodiment also includes an additive feeding box 10, the side wall of which is provided with a feeding port with a feeding door, and the feeding port is closed during feeding to achieve closed feeding.

[0047] The above arrangement can prevent dust from scattering and polluting the environment when adding materials, and avoid the pollution caused by dust spillage and the trouble of collecting and treating the spilled dust.

[0048] In the closed recovery system of the additive feeding powder of the polypropylene granulation unit of the present embodiment, one side of the breathing silo 2 is connected to an emptying port collecting tank 11, and the breathing silo 2, the emptying port collecting tank 11, the recovery tank 4 and the pipeline 3 are respectively provided with a pneumatic oscillator 12, and the pneumatic oscillator 12 generates vibration to shake off the attached powder.

[0049] A pneumatic oscillator 12 is installed on the outer wall of the breathing silo 2, and cooperates with the aeration head 6 in the back-blowing assembly to separate the powder attached to the filter element 5 and the inner wall of the breathing silo 2 through vibration, and drops into the recovery tank 4 through the pipeline 3. In order to prevent the powder from adhering to the equipment and the inner wall of the pipeline, a pneumatic oscillator 12 is installed on the pipeline 3 that runs through the third and fourth floor slabs, the emptying port collection tank 11, and the recovery tank 4.

[0050] Preferably, in order to prevent the pneumatic oscillator 12 from working at the same time and causing the granulation unit balance pipe and some equipment to resonate, the pneumatic oscillator 12 installed on the breathing silo 2, the emptying port collection tank 11, the recovery tank 4, and the pipeline 3 running through the third and fourth floors work separately, and each working time is 5 minutes. The pneumatic oscillator 12 works by sending a signal from the PLC and completing the required work according to the program.

[0051] In the present utility model, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "rotation" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, for ordinary technicians in this field, the specific meanings of the above terms in the utility model can be understood according to the specific circumstances.

[0052] Although the embodiments of the present invention have been shown and described in detail, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A closed recovery system for additive powder in a polypropylene granulation unit, characterized in that: It includes a breathing silo, in which an antistatic filter for filtering powder in the rising airflow is arranged, and the breathing silo is connected to a recovery tank through a pipeline, and the recovery tank is connected to the granulator hopper inlet line, so that the recovered powder and the powder sent into the granulator hopper by the system can be processed and granulated synchronously.

2. A closed recovery system for additive powder for polypropylene granulation unit according to claim 1, characterized in that: The antistatic filter comprises a filter element, and a plurality of the filter elements are provided, and the plurality of filter elements are symmetrically arranged around the central axis of the breathing silo.

3. A closed recovery system for additive powder of polypropylene granulation unit according to claim 2, characterized in that: The filter element is configured to be a hollow cylinder, the material of the filter element is polyester fiber, and an antistatic coating is provided on the surface.

4. A closed recovery system for additive powder of polypropylene granulation unit according to claim 2, characterized in that: A back-blowing assembly is arranged above the filter element, and the back-blowing assembly includes an aeration head. The jet end of the aeration head is directed toward the filter element to blow away the powder filtered on the filter element.

5. A closed recovery system for additive powder of polypropylene granulation unit according to claim 4, characterized in that: The backflush assembly also includes a gas tank, a pulse valve and a pressure regulating valve. The pulse valve is arranged between the gas tank and the aeration head. The gas in the gas tank is depressurized by the pressure regulating valve and then ejected from the aeration head through the pulse valve.

6. A closed recovery system for additive powder of polypropylene granulation unit according to claim 4, characterized in that: A partition is arranged in the middle of the filter element to divide the filter element into two groups. Two groups of aeration heads are arranged corresponding to the filter element. The two groups of aeration heads spray air alternately to back-blow the filter element.

7. A closed recovery system for additive powder of polypropylene granulation unit according to claim 1, characterized in that: A screw conveyor is arranged between the recovery tank and the granulator hopper inlet line, the discharge end of the recovery tank is connected to the feed port of the screw conveyor, and the discharge port of the screw conveyor is connected to the granulator hopper inlet line.

8. A closed recovery system for additive powder of polypropylene granulation unit according to claim 7, characterized in that: A tuning fork level meter is arranged in the recovery tank, and the tuning fork level meter is connected to the screw conveyor signal. When the powder in the recovery tank reaches a preset level, the tuning fork level meter sends a signal to control the operation of the screw conveyor to transport the powder in the recovery tank to the hopper inlet line of the granulator.

9. A closed recovery system for additive powder of polypropylene granulation unit according to claim 1, characterized in that: It also comprises an auxiliary agent feeding box, the side wall of which is provided with a feeding port with a feeding door, and the feeding port is in a closed state during feeding to realize closed feeding.

10. A closed recovery system for additive powder of polypropylene granulation unit according to claim 9, characterized in that: One side of the breathing silo is connected to an emptying port collecting tank, and the breathing silo, the emptying port collecting tank, the recovery tank and the pipeline are respectively provided with pneumatic oscillators, and the pneumatic oscillators generate vibrations to shake off the attached powder.

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