CONTINUOUS DRUM FILTER

Abstract

The utility model relates to the purification of suspensions by filtration and is intended for the purification of spent acid mixtures from nitrocellulose particles and other contaminants.A continuous-action drum filter comprising a cylindrical drum with a horizontal axis, driven in rotation by a drive system, wherein said drum has a longitudinal rectangular cross-section limited by an annular edge and a fluid supply unit containing a pipeline that allows for liquid filtration and sediment removal from said filter elements, the sediment removal system is gravity-flowing in the form of a collector located inside the drum, 6 removable sections with a filter mesh are mounted on the end surface of the drum, two rows of nozzles are mounted above the funnel on the body for supplying compressed air or acid / liquid for cleaning the filter mesh of the drum, a perforated pipe is rigidly attached along the perimeter of the funnel, through which liquid for washing nitrocellulose (NC) is supplied from the funnel to the receiving one, the filter is equipped with a frequency converter and a level sensor. 3 ill.

Description

[0001] The utility model relates to the purification of suspensions by filtration and is intended for purifying spent acid mixtures from nitrocellulose particles and other contaminants.

[0002] A drum vacuum filter is known from the existing level of technology, consisting of a bath and a drum, which is mounted on coaxial supports with the possibility of rotation inside the bath, wherein the cylindrical surface of the drum is made of perforated sheets with filter fabric, and radially located spokes are installed at the ends of the drum, to which journals are attached, while the material used for the spokes is a material resistant to the effects of an aggressive environment (see patent No. RU 210203, IPC B01D 33 / 06, published 03 / 31 / 2022).

[0003] A drawback of the known device is that the mechanical particles retained by the filter are removed from the hopper after the liquid purification process is complete. This is done by turning off pumps 20 and 18 and allowing the suspension to settle in the turbocyclone body for 0.5-1 hour. The accumulated particles are then manually removed from the hopper into a container.

[0004] A filter for cleaning liquid from mechanical impurities is known, comprising a housing with inlet, outlet and flushing pipes and a filter element, wherein the filter element is made of a set of anti-corrosion replaceable plates fixed immovably in grooves or ledges of the housing, which has a rectangular cross-section, diagonally, and the required filtration fraction, periodic cleaning and self-cleaning are provided by intermediate plates rotating at an angle of more than 180 ° and less than 360 °, fixed in the splines of the output shaft with a manual drive handle, or by fixed washers laid between each plate, while a periodically opening flushing pipe is cut into the housing at the bottom vertically, and the cuts of the inlet and outlet pipes with shut-off and control valves can vary in their chambers in any direction (see patent No. RU 2251443, IPC B01D 29 / 46, B01D 35 / 02, published 10.05.2005).

[0005] The disadvantage of this filter is that it cannot be used for continuous cleaning, since the plates need to be removed.

[0006] A filter is known for purifying liquid or gas from mechanical impurities, comprising a housing with pipes and filter elements, and it is made two-stage, including, along the flow, a coarse cleaning stage in the form of fixed plates with end intermediate washers, the thickness of which determines the fraction of coarse filtration, and a fine cleaning stage mainly from super-strong fibers of filter material stretched on a frame frame, fixed at one end to a drive shaft located in the center of a circle, the arc of which is a plate of the coarse cleaning stage, and the other - to a comb in the form of plates or super-strong strings passing between the plates of the coarse cleaning stage, ensuring their cleaning by the movement of the comb between them along their entire length when the drive shaft is turned,in this case, to ensure cleaning of the filter material of the fine cleaning stage, the filter is equipped with a source of ultrasonic vibrations for liquid or a low-power vibrator for gas (see patent No. FR 2808458, IPC B01D 21 / 00 B01D 24 / 46 B01D 33 / 06 B01D 33 / 067 B01D 33 / 44 B01D 33 / 58, published 09.11.2001).

[0007] The disadvantage is the vibration caused by ultrasonic vibrations. The filter material also requires replacement, meaning it's impossible to create a continuous cleaning cycle.

[0008] The closest to the claimed technical solution in terms of the set of essential features is a continuous drum filter for filtering a liquid, such as a solution containing sediment (suspension) a continuous drum filter (10) for filtering a liquid, such as a solution containing sediment, containing a cylindrical drum (16) with a horizontal axis, driven into rotation by a drive system (22), wherein said drum (16) has a longitudinal cross-section of a rectangular shape with a vertical wall (16a), a cylindrical wall (16b) and an axial opening (16e), limited by an annular edge (16c), which continues the cylindrical wall, a plurality of filter elements (60), each of which is oriented in the axial direction and forms at least part of the cylindrical wall (16b) of the drum (16), wherein each of the filter elements (60) communicates with a branch channel (62), a feed system (28) liquid to be filtered,fed through said opening (16e) into the drum (16), a sediment drainage system (30, 36), a drainage system (34) for filtrate passing through said drainage channels (62), and a fluid supply unit comprising a pipeline (64) for pulsed supply of compressed air and means (65, 66) for forcibly inducing said liquid to pass through filter elements (60), wherein said fluid supply unit is configured to communicate with said drainage channels by means of a connecting system (40) that allows for angular distribution of the operations performed by the filter, including at least filtration of the liquid and removal of sediment from said filter elements by means of blowing, wherein said drive system (22) comprises a drive shaft (18) concentric with the drum (16), rigidly connected to it at the level of said vertical wall (16a) and located on the side of the drum (16) opposite to said opening (16e),said means for forcing said liquid to pass through the filter elements comprise a suction filtration pipeline (65) which communicates with said filtrate drainage system (34) and creates a vacuum behind said filter elements (60) in relation to the internal cavity of the drum (16), said sediment drainage system is gravity-flowing in the form of a collector (36) located inside the drum (16), essentially under its uppermost part and communicating with a discharge channel protruding beyond the drum (16) through said opening, said discharge channels (62) pass inside said vertical wall (16a) of the drum (16) and have a first end (62a) communicating with the filter element (60), and a second end (62b) extending onto the vertical outer surface of said vertical wall (16a), said connecting system (40) comprises a first disk (44),rigidly connected to the drum (16) around the drive shaft (18) and provided with several connecting windows (44a), each of which communicates with the second end (62b) of one of the said branch channels (62), and a second, fixed, disk (46), mounted coaxially next to the said first disk (44) and provided with angular channels (46a-46d) interacting with the said fluid supply unit and located radially opposite the said connecting windows (44a), wherein the angular channel (46a) of filtration is located at least partially in the lower part of the second disk (46) and communicates with the said suction pipeline (65) of filtration, and the angular channel (46c) of sediment collection is located, essentially, in the highest angular sector of the second disk (46) and communicates with the said pipeline (64) for supplying compressed air for removing sediment from each filter element (60), the cylindrical wall (16b) of the said the drum (16) is equipped with supports (80),each of which is oriented in the axial direction and which are spaced around the circumference at a uniform pitch, each filter element (60) is located on the said supports (80) in such a way as to cover the entire cylindrical wall (16b), wherein each filter element (60) is installed removable with the possibility of sliding in the axial direction relative to the said supports (80) (see patent No. RU 2271853, IPC B01D 33 / 06, published 20.03.2006).,

[0009] The disadvantage is the complicated cleaning system.

[0010] A drawback of the known device is that the mechanical particles retained by the filter are removed from the hopper after the liquid purification process is complete. This is done by turning off pumps 20 and 18 and allowing the suspension to settle in the turbocyclone body for 0.5-1 hour. The accumulated particles are then manually removed from the hopper into a container.

[0011] The task was to create a continuous-action drum filter with high performance characteristics.

[0012] The stated problem is solved in that a continuous-action drum filter comprising a cylindrical drum with a horizontal axis, driven in rotation by a drive system, wherein said drum has a longitudinal rectangular cross-section limited by an annular edge and a fluid supply unit containing a pipeline that allows for liquid filtration and sediment removal from said filter elements, the sediment removal system is gravity-flowing in the form of a collector located inside the drum, 6 removable sections with a filter mesh are installed on the end surface of the drum, two rows of nozzles are installed above the funnel on the body for supplying compressed air or acid / liquid for cleaning the filter mesh of the drum, a perforated pipe is rigidly attached along the perimeter of the funnel, through which liquid is supplied for washing nitrocellulose (NC) from the funnel to the receiving one, the filter is equipped with a frequency converter and a level sensor.

[0013] The presence of 6 removable sections with a filter mesh allows you to quickly carry out repair work by replacing part of the structure, rather than the entire drum.

[0014] The discharge hopper collects filtered NC particles. It is a conical funnel with a rectangular cross-section at the top.

[0015] The body is equipped with two rows of nozzles for supplying compressed air or acid / liquid to clean the filter mesh of the drum, which ensure high quality cleaning of the filter mesh.

[0016] The frequency converter allows you to adjust the rotation speed.

[0017] The level sensor protects the device from overflow.

[0018] The filter design allows for continuous operation, which improves labor productivity and ensures safe working conditions.

[0019] An analysis of known technical solutions, carried out using scientific, technical and patent documentation, showed that the set of essential features of the claimed technical solution is not known from the state of the art, therefore, it meets the patentability conditions of “novelty”.

[0020] The claimed technical solution is illustrated by drawings:

[0021] Fig. 1 - general sectional view;

[0022] Fig. 2 - left view of the tray.

[0023] Fig. 3 - tray.

[0024] A continuous-action drum filter 1 comprising a cylindrical drum 2 with a horizontal axis, driven into rotation by a drive system, wherein said drum 2 has a longitudinal rectangular cross-section limited by an annular edge 3 and a unit 4 for supplying fluids with the help of a branch pipe 5, containing a pipeline 6 that allows for the filtration of liquid and the removal of sediment from said filter elements, the sediment removal system is gravity-flowing in the form of a collector 7, from the collector through a nozzle 8 located inside the drum 2, six removable sections 9 with a filter mesh 10 are installed on the end surface of the drum, two rows of nozzles 12 are installed above the funnel 11 on the body 1 for supplying compressed air or acid / liquid through branches 13 for cleaning the filter mesh 10 of the drum 2, a perforated pipe is rigidly attached along the perimeter of the funnel 11 14,into which, through the branch pipe 15, the liquid for washing off nitrocellulose (NC) is supplied from the funnel 11 through the fitting 8 into the receiving tank or returned to the centrifuge, the filter 1 is equipped with a frequency converter (not shown in the drawing) and a level sensor (not shown in the drawing), which is installed in the fitting 16. For replacing the worn mesh 10, a hatch 17 is provided. The hatch design includes an inspection window (not shown in the drawing) for visual monitoring of filtration and the condition of the drum.

[0025] The design of the device includes a pipe 18 for washing and a pipe 19 for extracting acid vapors for absorption.

[0026] Filter drum 1 is driven by an electric motor, and the speed of drum 2 can be controlled by a frequency converter. Spent acid enters drum 2 through pipe 5, flows through filter mesh 10 into filter housing 1, and exits through pipe 6. NC particles settle on mesh 10. Compressed air or acid is supplied through two rows of slot nozzles 12 located in the upper part of the housing via pipes 13. A stream of air or acid knocks the NC particles off mesh 10 and into receiving funnel 11. Acid is fed into receiving funnel 11 through perforated pipe 14 via pipe 15 to flush the NC particles out of filter housing 1 through pipe 8. The design includes a level sensor (pipe 16). When filter 1 overflows, excess acid drains into an intermediate tank and is then pumped back into the filter. Purified acid is sent to intermediate tanks or for regeneration and further use in the process.

[0027] During routine maintenance, hatch 17 is used to replace worn-out screens and perform other repairs. The inspection window in hatch 17 allows visual inspection of the filtration process and the condition of drum 2 during operation.

[0028] This drum filter is reliable and safe, made of special corrosion-resistant metals.

[0029] The claimed technical solution meets the requirements for industrial applicability and can be manufactured on standard equipment using modern materials and technologies. It has been tested at the Kazan State Gunpowder Plant, and all the stated technical results have been achieved, significantly exceeding the known performance of similar installations known as of the filing date of this application.

Claims

A continuous-action drum filter comprising a cylindrical drum with a horizontal axis, driven in rotation by a drive system, wherein said drum has a longitudinal rectangular cross-section limited by an annular edge and a fluid supply unit containing a pipeline that allows for liquid filtration and sediment removal from said filter elements, the sediment removal system is gravity-flowing in the form of a collector located inside the drum, characterized in that 6 removable sections with a filter mesh are installed on the end surface of the drum, two rows of nozzles are installed above the funnel on the body for supplying compressed air or acid / liquid for cleaning the filter mesh of the drum, a perforated pipe is rigidly attached along the perimeter of the funnel, through which liquid is supplied for washing nitrocellulose (NC) from the funnel to the receiving one, the filter is equipped with a frequency converter and a level sensor.

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