RU2592709C1 - Device for mechanical removal of sediment from settling tank - Google Patents

Abstract

FIELD: processing and recycling of wastes.

SUBSTANCE: invention relates to treatment of effluents and can be used in settlers. Device for mechanical removal of sediment from a settling tank comprises bearing frame 1 and group of scrapers 2, which have a kinematic connection with bearing frame 1 and with each other. Kinematic connection of each scraper 2 with bearing frame 1 is formed of at least four bearing rods 3 combined into a rectangular structure, one end of which has a hinged connection with bearing frame 1, and the other one has a hinged connection with corresponding bearing frame 6. Scraper 2 is rigidly connected with bearing frame 6 and between its lower edge and bottom 7 of settling tank 4 there is formed a clearance changing during displacement of scraper 2 over the bottom under the action of the formed ahead of it dump of sludge.

EFFECT: invention allows to increase longevity of operation of scrapers with preservation of the bottom surface of the settling tank and to efficiently remove the sediment.

1 cl, 3 dwg

Description

The present invention relates to wastewater treatment systems used in aeration stations for drinking water and wastewater and other industrial and domestic wastewater treatment plants, and may find application in their sumps for the mechanical collection and removal of sediment from suspended wastewater of suspended particles of insoluble substances.

A device is known for the mechanical removal of sediment from a radial sump (see certificate of the Russian Federation for utility model No. 30613, published on July 10, 2003). It is intended for mechanical raking of sludge into a sludge pit at the bottom of the radial settler and contains an active carrier (a bridge equipped with a drive), on which a tool is mounted that makes complex movement along the bottom of the radial settler with a portable movement around the center of the radial settler and with periodic relative movement along a circular arc from the bottom border to the silt pit. In this case, the sediment is removed from the bottom in stages in separate strips overlapping one another in succession and formed with a tool scraping along the bottom of the radial sump. As a result of repeated scraper movements of the tool simultaneously with the removal of sediment, the bottom is cleaned, which is the advantage of this equipment, since the bottom cleaning prevents the formation of local zones of adhering sediment on it, which compacts, rots and floats to the surface, reducing the quality of water treatment. The specified known device for mechanical removal of sediment returns the radial sump to its original state within one cycle of the portable movement of the tool.

However, this advantage also turns out to be a drawback, since during scraper movements of the tool along the bottom of the radial settler, the working edge of the instrument is abraded, the replacement of which requires the functioning of the device for mechanical removal of sediment from the radial settler.

A device is known for the mechanical removal of sediment from a radial sump (see USSR author's certificate No. 464536, published on March 25, 1975), containing an active carrier, which is a bridge equipped with a drive and used as a surface part, and an underwater part in the form of a truss connected to the drive axle, and also having a working tool, which is a group of scrapers, in which the scrapers are arranged in a row in a spiral line and connected by adjacent edges to each other through hinges, each scraper has a JCOMM held together with him carrying rod hinged to the farm and the scraper is moved along the bottom of the radial settler tight to the bottom of it.

This well-known technical solution is selected as a prototype, so it has the largest number of essential features in common with the claimed technical solution.

In fact, the prototype is a device for the mechanical removal of sludge from the sump, containing a supporting truss and a group of scrapers, which have a kinematic connection both with the supporting truss and with each other, forming together at the bottom of the sump, at least one dump for removing sludge from sump, while the lower edge of each scraper scraper the bottom of the sump in the process of moving the scraper under the action of the bearing truss.

However, during the cycle, the movement of the scrapers along the bottom of the sump, performed invariably in one direction, causes the scrapers to grind and the bottom of the sump is scraped off. As a result, you often have to stop this device and replace its scrapers, as well as restore the bottom surface of the sump.

The objective of the present invention is to provide a new device for the mechanical removal of sludge from the sump with the technical result, which is to increase the durability of the scrapers while maintaining the bottom surface of the radial sump during the rapid removal of sludge deposited on the bottom from wastewater.

The problem is solved as follows.

A device for the mechanical removal of sludge from a sump containing a supporting truss and a group of scrapers that have a kinematic connection both with the supporting truss and with each other, forming together at least one dump at the bottom of the sump, characterized in that the kinematic connection of each scraper with a supporting truss is formed of at least four load-bearing rods combined in a rectangular structure, in which one end is pivotally connected to the supporting truss, and the other is pivotally connected to the supporting corresponding frame, m the scraper is rigidly connected to the aforementioned supporting frame and a gap is formed between its lower edge and the bottom of the settler, which changes during the movement of the scraper above the bottom under the action of the draft dump formed in front of it.

This new technical solution allows you to create a device for the mechanical removal of sludge from the sump, which ensures the achievement of the following technical result, namely: it increases its durability while maintaining the surface of the bottom of the sump and the prompt removal of sludge from wastewater. This is achieved due to the fact that the kinematic connection of the scraper and the active carrier is formed by a rectangular structure, one of the ends of which is pivotally connected to the active carrier, and the other to the frame under which the scraper is located and to which it is connected. As a result, when moving the scraper above the bottom of the sump, the scraper collects precipitation during its movement, smoothly monitors the profile (surface irregularities of the bottom of the sump), forming a prismatic roll from it and directing it to the sediment collection pit. In this case, between the lower edge of the scraper and the bottom of the sump, a layer of sediments forms on its surface, which acts as a lubricant between these elements moving relative to each other. Therefore, the scraper automatically deviates depending on the resistance of the sediment accumulated in front of it to the perimeter movement of the device without the formation of sediment in stagnant and decaying zones, since a slip layer is formed between the bottom edge of the scraper and the bottom of the radial settler, which fulfills the lubrication conditions. In addition, the presence of a kinematic connection made in the form of a rectangular structure of at least four rods and pivotally connected to the scraper on the one hand and pivotally connected to the supporting truss on the other hand allows it to provide a smooth and elastic flow around the bottom of the sump with the scraper. Moreover, the swivel of a rectangular structure from rods with a supporting truss has elastic properties higher than the elastic properties of the swivel joints of the said rectangular structure with staples. Changing or adjusting this ratio of the elastic properties of the articulated joints allows you to adjust the movement of the scraper along the bottom of the sump with the required force.

The applicant has conducted a patent search on this topic. He showed that the proposed combination of essential features was not found. Therefore, this invention can be considered a new invention.

The essence of the invention and its practical performance is illustrated by the drawings and the following description.

FIG. 1 - frontal section of the device for the mechanical removal of sediment from the sump;

FIG. 2, 3 - two working positions of the scraper at the bottom of the sump with the kinematic connection of the scraper with the supporting truss.

The proposed device for the mechanical removal of sludge from the radial sump contains a supporting truss 1 and a group of scrapers 2. Each scraper 2 has a kinematic connection both with the supporting truss and with each other, forming together at the bottom of the sump (conventionally shown in the drawing) (Fig. 1) at least one dump from sewage sludge. The kinematic connection of each scraper 2 with the supporting truss 1 is formed of at least four supporting rods 3, combined in a rectangular structure (Fig. 2), in which one end is pivotally (upper hinges 4 of the supporting truss) connected to the supporting truss 1, and another pivotally (lower hinges 5) is connected to the corresponding supporting frame 6. Moreover, the scraper 2 is rigidly connected to the said supporting frame 6 and a gap h is formed between its lower edge and the bottom 7 of the settler 4 (conventionally shown in the drawing) (Fig. 2), changing in the process of moving the scraper 2 over d 7 th by the action of the blade formed in front of him cake. Moreover, as supporting rods 3 can be applied pipes. Each four of them is mounted on one side on hinges 4 with the bottom of the supporting truss 1, and on the other, with the frame 6 through the hinge 5, to the bottom of which the scrapers 2 are rigidly attached. As a result, four supporting rods 3 (pipes) through the hinges 4 and 5 in the initial state they form a rectangle (Fig. 2), and when the resistance meets while moving above the bottom 7 of the sump - parallelogram (Fig. 3). The result is an automatic deflection of the scraper 2 depending on the resistance of the sediment accumulated in front of it to the perimeter movement of the device without the formation of sediment in the stagnant and decaying zones, since a thin slip layer is formed from the sewage sludge between the lower edge of the scraper 2 and the bottom of the sump, satisfying the lubrication conditions, which prevents wear of the lower edge of the scraper 2 and the formation of a thin even protective coating of the bottom surface of the radial sump (the drawing is conventionally shown as thicknesses us h sediment layer, FIG. 3). Moreover, the articulated joint of a rectangular structure from rods with a supporting truss has elastic properties higher than the elastic properties of the articulated joints of the said rectangular structure with scrapers. Changing or adjusting this ratio of the elastic properties of the articulated joints allows you to adjust the movement of the scraper along the bottom of the sump with the required force. In fact, the elastic properties of the articulated joint of the rectangular design of the rods with the supporting truss during the next collision of the scrapers with an enlarged draft shaft contribute to its displacement along the bottom of the radial sump.

The proposed device mounted on the sump works as follows.

Wastewater arriving for treatment is fed in a continuous stream into the sump bowl through a central inlet pipe. While the wastewater is in the sump bowl, they are treated both due to the physical processes of the formation of agitated particles at the bottom of the sump, and the chemical and biological processes of the formation of various organic coagulants, which also sink to the bottom 7 of the sump, entraining smaller particles. Thus, a sludge layer forms at the bottom of the sump. The carrier farm 1, relying in the present case on a movable support 8, moving along the side 9 of the bowl of the sump, moves the main scrapers 2 and additional scrapers (not indicated) along the bottom 7. At the same time, a drawing prism is formed from the sediment in front of the dump, sent to the silt pit 10 due to the shape of the main scrapers 2 in the plan. The additional scrapers installed in front of the dump when moving along the bottom 7 are inserted at an acute angle into the mass of the removed sediment, they are divided into parts and cut from the bottom surface, shifting each part of the massif separately in the direction that intersects with the direction of movement of the main scrapers 2. Due to This achieves the effect of improving the quality of bottom cleaning, since the mechanical effect on the removed sludge, which prevents its dumping into the sludge pit, prevents the sediment from sticking to the bottom. In this case, the direction of the indicated shift depends on which side relative to the silt pit additional scrapers are deployed. The effect of improving the quality of cleaning the bottom, of course, is achieved only if the size and location of the additional scrapers provide them with passage through the entire cleaned surface of the bottom of the sump. The connection of the main scrapers 2 by hinges 5 allows the main scrapers 2 to rotate relative to each other in a vertical plane and to fit in the best way to the unevenness of the bottom 7, which also improves the cleaning quality of the bottom 7. It should also be noted that the presence of hinges 5 is optional; Improving the fit to the bottom 7 of the sump bowl can be achieved, for example, by selecting the appropriate flexibility of the blade as a whole or by setting certain requirements for bottom irregularities 7 to ensure compatibility between the equipment and the sump.

Based on the experiments and conditions laid down in the calculation of sediment raking forces, the shape of the section prism is a figure close to a right triangle with hypotenuse located at an angle of 45 ° to the bottom surface of the sump, and the leg of this triangle does not exceed the height of the main scraper ( not shown in the drawing) (see, for example, the dissertation of V.I. Morozova “Research and development of rational equipment for removing sludge from radial settlers”, L., 1979) Thus, the minimum clearance between shaft and additional scrapers, sufficient for the passage of the drawing prism along the blade, should be at least one height h of the main scrapers 2. Due to the fact that the drawing prism in cross section is an isosceles right triangle, the leg of which increases as the material raked approaches sediment to silt pit 10 in its relative movement along the dump, the height h of the main scrapers 2 should be greater by Ah and, accordingly, the distance between the additional scrapers and the main and scrapers should not be less than h. This condition will ensure unhindered passage of the drawing prism. Specific values of Δh and h are calculated from the load on the sump, expressed in the maximum amount of sediment falling to the bottom of the sump in mm / day. For example, the calculation of the equipment of a particular 54-meter primary sedimentation tank with a precipitation of up to 270 mm / day shows that it will not exceed 160 mm and the height of the main scrapers 250 mm is sufficient with a margin. Accordingly, at the same distance from the main scrapers 2, additional scrapers can be arranged. A feature of the proposed device is also that when turning the additional scrapers in the direction opposite to the silt pit 10, the effect of cleaning the bottom is enhanced by a sharper change in the direction of movement of the sludge, moved first by additional scrapers, and then by the main scrapers 2. At the same time, an additional effect of compensation of the radial the force acting on the blade resulting from the counter direction of the radial components of the reactive forces acting on the main 2 and additional ADDITIONAL scrapers.

Thus, the proposed device for the mechanical removal of sludge from the sump ensures efficient cleaning of the bottom of the sump with minimal energy consumption.

Claims (1)

A device for the mechanical removal of sludge from the sump, containing the supporting truss and a group of scrapers, which have a kinematic connection both with the supporting truss and with each other, forming together at the bottom of the sump at least one dump, characterized in that the kinematic connection of each scraper with the carrier the truss is formed of at least four load-bearing rods, united in a rectangular structure, in which one end is pivotally connected to the supporting truss, and the other is pivotally connected to the supporting corresponding frame, and approx rigidly connected with said carrier frame and between its lower edge and the bottom of the settler formed by a gap varying during the movement of the scraper over the bottom under the action generated before him blade precipitate.

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