Sand trap for removing sand and large mechanical inclusions

Abstract

The utility model relates to the field of mechanical treatment of wastewater and / or natural water and can be used in wastewater disposal and water treatment facilities for the preliminary removal of large mechanical inclusions and sand particles from a flow. A sand trap for removing sand and large mechanical inclusions comprises a housing including a vertical 1 and inclined 2 sections, pipes for supplying raw water 6, for draining purified water 7, and for removing accumulated sand 8. According to the utility model, the vertical section 1 is connected to an inclined section 2, which forms a right triangle in longitudinal section. In the vertical section 1, above the inlet to the inclined section 2, a perforated plate 9 is mounted with an inclination toward the side wall of the vertical section 1, to which a pipe 6 for supplying raw water is connected, and an inclined auger 10 is installed above the perforated plate 9.A flow arrester 11 in the form of a plate is installed under the inlet of the inclined section 2, located with a slope towards the side wall 3 of the inclined section 2. At a distance of 1 / 3 of the length of the inclined section 2 from the branch pipe 7 for draining purified water, a baffle 12 in the form of a plate is fixed above the inclined wall 4 of the section 2. The technical result of the utility model is to increase the efficiency of mechanical removal of large mechanical inclusions and sand particles from the flow by reducing the removal of sand particles from the housing. 4 c.p. phyl., 2 fig.

Description

[0001] The utility model relates to the field of mechanical treatment of waste and / or natural waters and can be used in wastewater disposal and water treatment facilities for the preliminary removal of large mechanical inclusions and sand particles from the flow.

[0002] A mechanical wastewater treatment unit (RU 15110, cl. E03F 5 / 14, 20.09.2000) is known from the prior art. It comprises a housing supported on supports, a grate, a grate cleaning device, a conveyor or special container, and an electric motor with a drive. The grate is designed as a closed, continuous chain with catch hooks attached to it at a distance of (1.5-2) - (5-6) mm from each other and is mounted in the housing to ensure continuous movement.

[0003] However, the known unit is designed only for extracting large inclusions.

[0004] A sand trap (RU 2437702, class B01D 21 / 28, 2022) is also known, containing a tank in which wastewater moves at a speed of 0.1-0.3 m / s, depending on the size and density of the settling particles. The tank has a reinforced concrete body, buried in the ground and made in the form of a rectangular parallelepiped with a horizontal base reinforced with a perforated metal sheet, two vertical walls, and two end walls. A lid with an opening and a hatch for removing sludge is mounted on top of the body, which is connected to a removable cover slab of the sand trap with openings for storm drains. A vibrating chute, mounted on a shock-absorbing mat, is mounted on the base, which serves to more effectively remove sludge during cleaning of the sand trap. In the vertical wall there is a pipeline for supplying wastewater, and in the opposite vertical wall there is a pipeline for discharging wastewater into the sewer with a pocket for discharging

[0005] However, this device does not have the ability to remove large inclusions; as a rule, large inclusions are removed by separate grates before the sand trap.

[0006] The device for cleaning surface wastewater, made in a recessed design (RU 207418, cl. C02F 1 / 40, E03F 5 / 14, 10 / 27 / 2021), comprising a body made of pipes with technical wells, with hatches for servicing the process equipment, pipes for feeding the original wastewater for treatment and removing the purified water, consisting of a vertical section with a hatch for servicing the process equipment and a hopper located in its lower part with a conical bottom for sediment and a device for removing sediment, as well as an inclined section located with a slope towards the vertical section, with a device for collecting oil products located in the inclined section, a thin-layer settling module consisting of plane-parallel plates, a device for transporting sediment with a pipe for feeding wash water and jet-directing nozzles, semi-submersible and overflow baffles. The body is made of fiberglass pipes.The vertical section of the housing is equipped at the top with an open hydrocyclone with a tangential branch connected to the feedwater inlet for treatment, and a sludge discharge pipeline with a gate valve and a check valve installed on it. The slope of the inclined section toward the vertical is no more than 3°. The housing at the junction of the vertical and inclined sections is equipped with a baffle plate, which does not extend to the bottom of the junction, being solid at the top and perforated at the bottom. A thin-layer settling module, an oil product collection device (an oleophilic belt skimmer), a semi-submersible and overflow baffle, and a submersible pump connected to the treated water outlet pipe are installed in series along the length of the inclined section. The sludge transport device with a wash water inlet pipe and jet guide nozzles is made of two parallel pipelines.Each pipeline is equipped with a nozzle located below the perforated section of the partition, installed at the junction of the vertical and inclined sections, equidistant from the conical bottom of the bin. The slope of the bin's conical bottom walls to the horizontal is 45-60°, and the slope of the thin-layer settling module plates is 60°.

[0007] The disadvantage of the known device is the complexity of the design, and in addition, it is aimed mainly at cleaning wastewater from suspended solids, oil products, biological and chemical oxygen demand (BOD and COD, respectively) and is not effective for cleaning water for water treatment and pre-removal from the flow of large mechanical inclusions over 5 mm and small sand particles up to 0.2 mm.

[0008] The task that the utility model is aimed at solving is the creation of a sand trap that is free from the disadvantages of known designs with the possibility of using it for water treatment for further use in production.

[0009] The technical result of the utility model is to increase the efficiency of mechanical removal of large mechanical inclusions and sand particles from the flow by reducing the removal of sand particles from the housing.

[0010] The stated problem and technical result are achieved by a sand trap for removing sand and large mechanical impurities, comprising a housing comprising vertical and inclined sections, pipes for feeding raw water, for draining purified water, and for removing accumulated sand. According to the utility model, the vertical section is connected to the inclined section, which forms a right triangle in longitudinal cross-section. A perforated plate is mounted in the vertical section above the inlet of the inclined section, inclined toward the side wall of the vertical section, to which the raw water supply pipe is connected, and an inclined auger is mounted above the perforated plate. A flow arrester in the form of a plate located at an angle toward the side wall of the inclined section is installed below the inlet of the inclined section. A baffle plate is fixed above the inclined wall of the section at a distance of 1 / 3 of the length of the inclined section from the pipe for draining purified water.

[0011] The inclined section's right-angled cross-section includes acute angles of 18° on the purified water discharge side and 72° on the accumulated sand removal side. This inclined section shape ensures that sand particles roll down to the bottom of the section under gravity. The accumulated sand is removed during backwashing. According to calculations, these angles stabilize the water flow, reducing its initial velocity and, consequently, the velocity of the transported particles, preventing them from leaving the sand trap tank with the purified water.

[0012] The perforated plate and flow damper are positioned parallel to the inclined wall of the inclined section of the housing. This arrangement increases the path taken by the water flow, reducing its initial velocity and reducing turbulence at the outlet of the inclined section.

[0013] The combination of the vertical and inclined sections allows for the combined retention of large debris over 5 mm, which are separated by a perforated plate in the vertical section and removed by the auger, and fine sand particles down to 0.2 mm in the inclined section. This design saves space by combining the functionality of two separate units.

[0014] The location of the perforated plate in the vertical section before the entrance to the inclined section at an angle to the side wall of the vertical section with a slope towards the entrance to the inclined section ensures the separation of large particles of debris over 5 mm and their subsequent removal using a screw.

[0015] The presence of an inclined auger located above the perforated plate ensures the removal of debris and large inclusions from the water flow supplied for cleaning, which are retained by the surface of the perforated plate.

[0016] The presence of a flow damper plate under the inlet of the inclined section reduces the liquid velocity and increases the flow path. This creates conditions for more intensive gravitational settling of sand particles. Furthermore, the flow is stabilized and becomes less turbulent.

[0017] The presence of a baffle plate, located at a distance of 1 / 3 of the length of the inclined section, in front of the pipe for draining purified water above the inclined wall of the section, additionally slows down the flow of liquid, changing its trajectory of movement, helping to reduce the removal of precipitated particles, thereby increasing the efficiency of water purification.

[0018] It is advisable to fix the baffle plate above the inclined wall at a distance of 15 mm to 20 mm to prevent the accumulation of particles that overcome the baffle plate, but under the force of gravity cannot escape from the sand trap and slide back.

[0019] The utility model is illustrated by the following drawings.

[0020] Fig. 1 shows a cross-section of the sand trap;

[0021] Fig. 2 - illustrates the movement of water flow in a sand trap.

[0022] The utility model is explained by the following positions:

[0023] 1 - vertical section of the body;

[0024] 2 - the inclined section of the body in cross-section forms a right triangle with acute angles of 18° and 72°;

[0025] 3 - side wall of inclined section 2;

[0026] 4 - inclined wall of section 2;

[0027] 5 - longitudinal wall of inclined section 2, which is connected with vertical section 1;

[0028] 6 - ​​branch pipe for supplying source water for purification, located on the side wall of vertical section 1;

[0029] 7 - a branch pipe for draining purified water, located on the side of the inclined section angle of 18°;

[0030] 8 - a branch pipe for removing accumulated sand during flushing, located on the side with an inclination angle of 72°;

[0031] 9 - a perforated plate mounted at an angle to the side wall of the vertical section 1 from the side of the branch pipe 6 for supplying the source water for purification;

[0032] 10 - inclined auger for removing large particles trapped on the perforated surface of the plate;

[0033] 11 - flow damper, made in the form of a plate located at an angle to the side wall of inclined section 2;

[0034] 12 - a bumper in the form of a plate, fixed above the inclined wall of section 2.

[0035] The sand trap works as follows.

[0036] Through the pipe 6 for feeding the source water for purification, the contaminated water enters the vertical section 1 and falls onto the inclined perforated surface of the plate 9, on which debris and large inclusions are retained and removed outside the section 1 using the inclined screw 10.

[0037] Then the feed water, purified from coarse sand and inclusions, enters inclined section 2, striking flow arrester 11, where the flow velocity decreases and its direction changes sharply, acquiring an increase in flow velocity, forming nonlinear chaotic flows of water jets that disturb the environment, increasing the flow path. Due to the chaotic flow of water jets, conditions are created for more intense gravitational settling of sand particles, which pass between the boundary of arrester 11 and the side wall 3 of inclined section 2, hit inclined wall 4 of section 2 and roll down it, to branch pipe 8 due to the angle of wall 4 of 72°. The water flow then passes towards branch pipe 7 for removing purified water, located on the side of the inclined section with an angle of 18°. A baffle 12 is installed on the flow path at a distance of 1 / 3 of the length of section 2 from the branch pipe 7.The water flow additionally changes the trajectory of movement, which promotes the sedimentation of smaller particles and reduces their removal from the inclined section 2.

[0038] The sand accumulated in the lower part of section 2 is removed through pipe 8 during flushing, which is carried out periodically through inlet pipe 6, washing out all the accumulated sand.

[0039] The utility model can be manufactured industrially using known technologies for the production of housings, perforated elements, screw assemblies, and pipes. The device can be used in mechanical wastewater and / or natural water treatment plants as a standalone pre-treatment unit.

Claims

1. A sand trap for removing sand and large mechanical inclusions, comprising a body including a vertical and inclined section, pipes for feeding raw water, for draining purified water, for removing accumulated sand, characterized in that the vertical section is connected to the inclined section, which in longitudinal section forms a right-angled triangle, while in the vertical section above the entrance to the inclined section a perforated plate is mounted with an inclination towards the side wall of the vertical section, to which the pipe for feeding raw water is connected, and an inclined auger is installed above the perforated plate, in addition, under the entrance to the inclined section a flow damper is installed in the form of a plate located with an inclination towards the side wall of the inclined section, and at a distance of 1 / 3 of the length of the inclined section from the pipe for draining purified water above the inclined wall of the section a baffle in the form of a plate is fixed.

2. A sand trap according to paragraph 1, characterized in that the cross-section of the inclined section is made in the form of a right triangle with acute angles of 18° and 72°.

3. A sand trap according to paragraph 1, characterized in that the branch pipe for draining purified water is located on the side of the inclined section at an angle of 18°, and the branch pipe for removing sand during washing is located on the side of the inclined section at an angle of 72°.

4. A sand trap according to claim 1, characterized in that the perforated plate and the flow arrester are located parallel to the inclined wall of the inclined section of the housing.

5. A sand trap according to paragraph 1, characterized in that the baffle is fixed above the inclined wall at a distance of 15 mm to 20 mm.

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