CN221933157U - High-efficient shallow sand setting pond - Google Patents

Abstract

The utility model provides a high-efficiency shallow sand basin, relates to the field of sewage treatment, and solves the problem that the sand basin is difficult to effectively separate water from gravel with smaller particles; the efficient shallow sand setting tank comprises a tank body, wherein an inlet flow equalizing part and a sand-water separation component are arranged in the tank body, and the inlet flow equalizing part is positioned on the side wall of the tank body and is used for guiding a sand-water mixture to a sand-water separation unit; the sand-water separation assembly comprises stacking plates and a steady flow part, all the stacking plates are fixed on the steady flow part, the stacking plates are obliquely arranged compared with the horizontal plane, a drainage interval is reserved between every two adjacent stacking plates, the drainage interval is communicated with an inner cavity of the steady flow part, water can flow through the drainage interval, and gravel entering the drainage interval can flow into the inner cavity along the stacking plates under the action of gravity; the sand-water separation component can obviously reduce the flow velocity of water flow, thereby improving the sand setting efficiency and sand setting effect. Greatly improves the treatment efficiency of floating oil, scum and grit, has compact structure, high performance and large treatment capacity.

Description

A high-efficiency shallow sedimentation tank

Technical Field

The utility model relates to the technical field of sewage treatment, in particular to a high-efficiency shallow sand settling tank.

Background Art

Industrial and Municipal Wastewater After being filtered through fine screens, municipal wastewater needs to be further pretreated, and a grit chamber is needed at this time. Through the treatment of the grit chamber, the sand particles in the water can be effectively removed to avoid damage to equipment, blockage of pipes, and impact on the reactor volume. In addition to the sand removal efficiency, the organic separation effect of the grit chamber is also very important. Simple and efficient separation of organic pollutants is an important operating indicator that the grit chamber must have. In urban urban sewage treatment, domestic and industrial wastewater treated with a grit chamber helps to reduce the load of the sedimentation tank. This ensures that the subsequent biochemical treatment unit can operate in a stable and efficient manner, while alleviating the wear of the inorganic suspended solids in the sludge on the water pump and pipes. In addition, this method can also promote the smooth utilization of sludge energy resources. There are many problems with traditional grit chambers, such as low sand separation efficiency, difficulty in removing organic matter, large footprint, and leakage risks, which lead to poor performance in treating water pollution.

There are many types of grit chambers, among which the most common ones can be divided into several types such as horizontal flow grit chamber, aerated grit chamber, dole grit chamber, and vortex grit chamber.

The applicant has found that the prior art has at least the following technical problems: the existing grit chambers generally have problems such as low sand-water separation efficiency, large floor space, and high energy consumption. In particular, the removal effect of particles with a particle size of about 0.2 mm is poor. This leads to the accumulation of sediment during the long-term operation of the subsequent biochemical process stage. These accumulation problems will not only damage the bottom aeration device, water pump and pipelines, but also damage the bottom aeration device, water pump and pipelines. Therefore, it is necessary to strengthen the removal of particles around 0.2 mm, so as to improve the operating efficiency of the entire treatment system.

Utility Model Content

The purpose of the utility model is to provide an efficient shallow sand settling tank to solve the technical problem that the sand settling tank in the prior art is difficult to effectively separate water from smaller particles of sand and gravel; the many technical effects that can be produced by the preferred technical scheme among the many technical schemes provided by the utility model are detailed as follows.

In order to achieve the above purpose, the utility model provides the following technical solutions:

The utility model provides an efficient shallow sand settling tank, comprising a tank body, an inlet flow equalizing part and a sand-water separation component arranged in the tank body, wherein the inlet flow equalizing part is located on the side wall of the tank body and is used to guide the sand-water mixture to the sand-water separation unit; the sand-water separation component comprises a stacking plate and a flow stabilizing part, wherein:

All the stacking plates are fixed on the flow stabilizing part, the stacking plates are inclined compared to the horizontal plane, and there is a drainage gap between adjacent stacking plates, the drainage gap is connected with the inner cavity of the flow stabilizing part, water can flow through the drainage gap, and the gravel entering the drainage gap can flow into the inner cavity along the stacking plates under the action of gravity.

Preferably, the sand-water separation assembly further comprises a support frame, and the stacking plates and the flow stabilizing portion are both fixedly connected to the support frame.

Preferably, the flow stabilizing portion is vertically arranged, and the flow stabilizing portion includes a shell, the inner cavity is located in the shell and passes through the upper and lower ends of the shell, and the stacking plates are arranged on one side or two opposite sides of the shell.

Preferably, among all the stacked plates located on the same side of the flow stabilizing portion, the stacked plates are arranged at intervals along the height direction of the flow stabilizing portion.

Preferably, the inlet flow equalizing portion includes, from top to bottom, a first ramp, a second ramp and a third ramp connected in sequence, and the inclination angle between the second ramp and the horizontal plane is greater than the inclination angle between the first ramp and the horizontal plane, and greater than the inclination angle between the third ramp and the horizontal plane.

Preferably, the high-efficiency shallow sand settling tank further includes a sand discharge assembly and a sand washing assembly. The sand discharge assembly is located below the inner cavity and is used to transport the settled sand and gravel to the sand washing assembly for cleaning.

Preferably, the sand discharge assembly comprises a screw and a spiral blade, the screw is rotatably arranged, the spiral blade is fixed on the screw, and the spiral blade can transport sand and gravel to the sand washing assembly when the screw rotates.

Preferably, the high-efficiency shallow grit chamber further comprises an aeration pipe, wherein the aeration pipe is located above the inlet flow equalizing portion and is used to inject fine bubbles into the oily wastewater to be treated.

Preferably, the high-efficiency shallow sand settling tank also includes a skimming part, which is located above the sand-water separation component. The skimming part is a tank body structure and can skim off the oil phase and scum by flotation.

Preferably, an overflow weir plate is provided on the pool body, the overflow weir plate is located at the water outlet side of the sand-water separation component, and a water outlet is provided on the overflow weir plate.

Compared with the prior art, the high-efficiency shallow grit chamber provided by the utility model has the following beneficial effects: the inlet equalizing part drains the oil-containing sand-water mixture to be separated to the sand-water separation component, and the water enters the drainage interval, the flow rate is reduced, and the water can pass through the drainage interval normally. Due to the reduced water flow rate, it is difficult for the gravel to pass through the drainage interval with the water. After the gravel enters the drainage interval between the stacking plates, it flows into the inner cavity of the flow stabilizing plate along the stacking plates under the action of gravity, thereby achieving efficient sand-water separation. The sand-water separation component can significantly reduce the water flow rate, thereby improving the efficiency and effect of enhanced grit settling. The high-efficiency shallow grit chamber greatly improves the efficiency of treating floating oil, scum and gravel, has a compact structure, high performance, and a large treatment capacity, and is particularly suitable for sewage purification in airports, industrial parks, and sewage treatment plants.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

Fig. 1 is a schematic diagram of the structure of an efficient shallow grit chamber;

FIG2 is a front view of the sand-water separation assembly;

FIG. 3 is a schematic diagram of the three-dimensional structure of the sand-water separation component.

In the figure, 1, inlet flow equalization part; 11, first ramp; 12, second ramp; 13, third ramp; 2, aeration pipe; 3, sand and water separation assembly; 31, stacking plate; 32, flow stabilization part; 321, shell; 322, inner cavity; 33, support frame; 34, drainage spacing; 4, screw; 5, slag skimming part; 6, sand washing assembly; 7, water outlet; 8, overflow weir plate.

DETAILED DESCRIPTION

In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the utility model.

In the description of the present invention, it should be understood that the terms "center", "length", "width", "height", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "side" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

The embodiment of the utility model provides a high-efficiency shallow sand settling tank, which greatly improves the efficiency of treating floating oil, scum and gravel, has a compact structure, high performance and large processing capacity, and is particularly suitable for sewage purification in airports, industrial parks and sewage treatment plants.

The technical solution provided by the utility model is described in more detail below in conjunction with Figures 1 to 3.

As shown in Figure 1, the high-efficiency shallow sand settling tank provided by the utility model includes a tank body, an inlet flow equalizing portion 1 and a sand-water separation component 3 arranged in the tank body, the inlet flow equalizing portion 1 is located on the side wall of the tank body, and is used to drain the sand-water mixture to the sand-water separation unit; referring to Figures 2 and 3, the sand-water separation component 3 includes stacking plates 31 and a flow stabilizing portion 32, wherein: all stacking plates 31 are fixed on the flow stabilizing portion 32, the stacking plates 31 are inclined relative to the horizontal plane, and there is a drainage gap 34 between adjacent stacking plates 31, the drainage gap 34 is connected with the inner cavity 322 of the flow stabilizing portion 32, water can flow through the drainage gap 34, and the gravel entering the drainage gap 34 can flow into the inner cavity 322 along the stacking plates 31 under the action of gravity.

Referring to FIG. 1 , the perspective in FIG. 1 shows the side of the sand-water separation component 3 , and FIG. 2 is a front view of the sand-water separation component 3 , and the sand-water mixture flows into the front of the sand-water separation component 3 , as shown in the perspective in FIG. 2 .

The high-efficiency shallow sand settling tank of the utility model has the following principle: the inlet equalizing flow part 1 drains the oil-containing sand-water mixture to be separated to the sand-water separation component 3. The reason why water can carry sand and gravel to flow is mainly that the water flow velocity is large enough. When the water enters the drainage gap 34, the flow velocity is reduced, and the water can pass through the drainage gap 34 normally, that is, the water flows through the sand-water separation component 3 through the drainage gap 34. Due to the reduced water flow velocity, it is difficult for the sand and gravel to pass through the drainage gap 34 with the water. After the sand and gravel enter the drainage gap 34 between the stacking plates 31, it first accumulates between the stacking plates 31, and flows into the inner cavity 322 of the flow stabilizing plate along the stacking plates 31 under the action of gravity. The direction of the arrow in Figure 3 indicates that the sand and gravel sink from the inner cavity 322, thereby realizing efficient sand and water separation. The sand-water separation component 3 can significantly reduce the water flow velocity, thereby improving the enhanced sand settling efficiency and sand settling effect.

Specifically, referring to Figures 2 and 3, the sand-water separation assembly 3 further includes a support frame 33, the support frame 33 is fixed in the pool body, and the stacking plate 31 and the flow stabilizing portion 32 are fixedly connected to the support frame 33. The flow stabilizing portion 32 is vertically arranged, and the flow stabilizing portion 32 includes a shell 321, an inner cavity 322 is located in the shell 321, and runs through the upper and lower ends of the shell 321, and the stacking plate 31 is arranged on one side or two opposite sides of the shell 321.

As shown in Figure 2, the oil-containing sand-water mixture flows through the sand-water separation component 3 along the viewing angle in Figure 2. As shown in Figure 3, since the drainage gap 34 is connected to the inner cavity 322 of the flow stabilizing part 32 (a through hole connecting the inner cavity 322 and the drainage gap 34 is provided on the side wall of the warm flow part), water can normally pass through the drainage gap 34 between the stacked plates 31 and flow through the sand-water separation component 3, while the sand and gravel enter the drainage gap 34 between the stacked plates 31, first accumulate between the stacked plates 31, and flow into the inner cavity 322 of the flow stabilizing plate along the stacked plates 31 under the action of gravity, thereby achieving the separation of water and sand.

The sand-water separation assembly 3 of the above structure can be stably fixed in the pool body, and the stacking plates 31 are connected to the opposite sides of the flow stabilizing part 32, which can improve the sand-water separation efficiency.

As an optional implementation, among all the stacked plates 31 located on the same side of the flow stabilizer 32 , the stacked plates 31 are arranged at intervals along the height direction of the flow stabilizer 32 , thereby improving the sand-water separation efficiency.

Among them, the inclination angle between the stacking plate 31 and the horizontal plane is 30-60°, the number of stacking plates 31 on each side is controlled at 3-20, and the spacing between the stacking plates 31 is controlled at 5-50mm; the flow stabilizer 32 is located between the stacking plates 31 on both sides, and its main function is to ensure that the water flow in the space at the end of the stacking plate 31 is low and to enhance the sand settling efficiency; the support frame 33 mainly supports the stacking plates 31 and the flow stabilizer 32.

As shown in Figure 1, as an optional embodiment, the inlet flow equalizing section 1 includes a first ramp 11, a second ramp 12 and a third ramp 13 connected in sequence from top to bottom, and the inclination angle between the second ramp 12 and the horizontal plane is greater than the inclination angle between the first ramp 11 and the horizontal plane, and greater than the inclination angle between the third ramp 13 and the horizontal plane.

Specifically, the first ramp 11 is connected to the oil collection pipe and the water pipeline, the third ramp 13 is located in the upstream section of the sand-water separation component 3, the first ramp 11 is inclined at an angle of 30-45° to the horizontal incoming liquid pipeline, the second ramp is inclined at an angle of 50-60° to the horizontal incoming liquid pipeline, and the third ramp 13 is inclined at an angle of 30-45° to the horizontal incoming liquid pipeline. The main function is to utilize the Coanda effect to ensure that the treated water is evenly distributed on the flow section in the high-efficiency shallow sand settling tank.

As an optional embodiment, as shown in FIG. 1 , the high-efficiency shallow sand settling tank further includes a sand discharge assembly and a sand washing assembly 6 . The sand discharge assembly is located below the inner cavity 322 and is used to transport the settled sand and gravel to the sand washing assembly 6 for cleaning.

The sand and gravel left in the inner cavity 322 of the flow stabilizing portion 32 falls into the sand discharge assembly, and the sand discharge assembly transports the sand and gravel to the sand washing assembly 6 for cleaning, thereby separating organic matter on the surface of the sand and gravel.

The sand discharge assembly adopts a screw 4 transmission system, and its main function is to transport the settled sand and gravel. As an optional embodiment, as shown in FIG1 , the sand discharge assembly includes a screw 4 and a spiral blade, the screw 4 is rotatably arranged, the spiral blade is fixed on the screw 4, and the spiral blade can transport the sand and gravel to the sand washing assembly 6 when the screw 4 rotates.

The screw 4 can be driven by a driving device such as a motor. Since the screw 4 is provided with spiral blades, the sand and gravel left in the inner cavity 322 of the flow stabilizing portion 32 falls between the spiral blades. As the spiral blades rotate with the screw 4, the sand and gravel are transported to the sand washing assembly 6.

The sand washing component 6 can adopt the spiral centrifugal pump and sand-water separator in the prior art, and use the high-speed shearing principle of the spiral centrifugal pump to clean the sand and gravel to separate the organic matter on its surface, and then use the sand and water separator to separate the liquid and solid. The separated sand and gravel are collected, and the water is returned to the main process through the reflux pipeline.

As an optional embodiment, referring to FIG. 1 , the high-efficiency shallow grit chamber further includes an aeration pipe 2 , which is located above the inlet equalizing portion 1 and is used to inject fine bubbles into the oily wastewater to be treated.

The aeration pipe 2 is used to inject a large number of fine bubbles into the oily wastewater to be treated to mix the gas and liquid evenly, thereby achieving the effects of preliminary sand washing and removing floating oil and scum by utilizing the flotation effect. A dissolved air release system, a gas-liquid mixing pump, a static mixer, and an ejector can be used.

As an optional embodiment, as shown in Figure 1, the high-efficiency shallow sand settling tank also includes a skimming part 5, which is located above the sand and water separation component 3 and is spaced no less than 20 cm from the sand and water separation component 3. The skimming part 5 is a tank body structure that can utilize flotation to skim off the oil phase and scum.

As an optional embodiment, as shown in FIG. 1 , an overflow weir plate 8 is provided on the pool body, the overflow weir plate 8 is located at the water outlet side of the sand-water separation component 3 , and a water outlet 7 is provided on the overflow weir plate 8 .

The water outlet 7 adopts an overflow weir plate 8 structure. After the treated water passes through the skimming part 5 for skimming, it enters the overflow weir plate 8 and overflows out of the main process through the water outlet 7 to complete the sand and water separation.

The high-efficiency shallow sand settling tank of the present embodiment is suitable for the purification of industrial and municipal sewage, and is particularly suitable for the purification of oily and sandy sewage. It can be realized by changing the number, inclination angle, spacing and other structural forms of the stacking plates 31 of the shallow sand-water separation component 3, or by adopting a series or parallel combination according to different requirements for the treatment effect and different working flow requirements.

The processing process and principle of the high-efficiency shallow grit chamber of this embodiment are as follows:

First, the treated water enters the inlet equalizing part 1 at a certain pressure and flow rate. When passing through the first ramp 11 and the second ramp 12, the Coanda effect is used to change the treated water from horizontal flow to oblique downward flow. Then, the cone angle of the third ramp 13 is reduced to produce a lifting effect on the treated water, and the oblique downward flow is gradually converted into a horizontal flow again. At this time, the treated water enters the surrounding area of the aeration pipe 2, and a gas-liquid mixed flow rich in micro-nano bubbles is formed by using a dissolved gas release system, a gas-liquid mixing pump, a static mixer, and an ejector. The aeration pipe 2 is used to inject a large amount of fine bubbles into the oily wastewater to be treated, so that the gas and liquid are mixed evenly, achieving the effects of preliminary sand washing and removing floating oil scum by air flotation effect. Subsequently, the treated water enters the sand-water separation component 3, and the drainage gap between the stacking plates 31 is used to form a shallow sedimentation effect to enhance the sand settling efficiency. The flow stabilizing part 32 is located between the stacking plates 31 distributed on both sides, which can ensure the stable sedimentation of the gravel after shallow separation. The sand and gravel after sedimentation and separation are transported to the sand discharge component by gravity, and the settled sand and gravel are transported out by the screw 4 transmission system. The transported sand and gravel are cleaned by the high-speed shearing principle of the spiral centrifugal pump in the sand washing component 6 to separate the organic matter on the surface, and then the sand and water separator is used for liquid-solid separation. The separated sand and gravel are collected, and the water is returned to the main process. The reflux pipeline can be set outside the main separation area. The oil phase and scum separated by flotation are skimmed by the skimming part 5 located at the top of the sand and water separation component 3. After the treated water is skimmed by the skimming part 5, it overflows out of the main process through the overflow weir plate 8 structure at the outlet 7 to complete the sand and water separation.

The high-efficiency shallow grit chamber of this embodiment has the following effects:

1. It has successfully achieved the organic combination of various sewage treatment technologies such as flotation and shallow sedimentation, and has greatly improved the efficiency of treating floating oil, scum and gravel. The entire separation system is exquisite in form, compact in structure, efficient in performance and large in processing capacity. It is especially suitable for sewage purification in airports, industrial parks and sewage treatment plants.

2. The sand-water separation component 3 can improve the sand-water separation efficiency. The inclined angle and the distance between the inclined plates can be adjusted according to the incoming liquid conditions to ensure the treatment effect. It can achieve long-term stable operation and has no rotating parts. It is easy to use, install, maintain and repair.

3. The high-efficiency shallow sand settling tank can adapt to large-volume sewage treatment, avoids batch parallel connection of small prototypes, reduces floor space, and has strong adaptability to sewage water quality fluctuations, changes in treatment volume, etc. It has high operational flexibility and can adapt to liquid level fluctuations.

4. The high-efficiency shallow sand settling tank can treat sewage in a closed, device-based and harmless manner, avoiding the random discharge of harmful gases, improving the operating environment, improving safety performance, and being beneficial to environmental protection.

5. The high-efficiency shallow sand settling tank adopts gravity separation, eliminating the need for external dynamic equipment to remove floating oil, foam scum and gravel, with obvious energy-saving effect and low operating cost.

Based on the rated processing capacity of ^500m3 /h, hydraulic retention time of 1 minute and other working conditions, the high-efficiency shallow grit chamber structure design and performance prediction were carried out. The results showed that the separation efficiency of sand and gravel with a particle size of 200 microns reached 99%, and the separation efficiency of sand and gravel with a particle size of 75 microns was also stable at more than 88%, with excellent overall performance.

The high-efficiency shallow grit chamber proposed in the embodiment of the present invention can be used not only for the treatment of industrial and municipal sewage with large treatment capacity, but also for places such as airports and industrial parks; it can even be used for municipal water treatment to remove sand therein.

In the description of this specification, specific features, structures or characteristics may be combined in an appropriate manner in any one or more embodiments or examples.

In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

The above is only a specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the utility model, which should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims (10)

1. An efficient shallow sand settling tank, characterized in that it comprises a tank body, an inlet flow equalizing part and a sand-water separation component are arranged in the tank body, the inlet flow equalizing part is located on the side wall of the tank body, and is used to guide the sand-water mixture to the sand-water separation unit; the sand-water separation component comprises a stacking plate and a flow stabilizing part, wherein: All the stacking plates are fixed on the flow stabilizing part, the stacking plates are inclined compared to the horizontal plane, and there is a drainage gap between adjacent stacking plates, the drainage gap is connected with the inner cavity of the flow stabilizing part, water can flow through the drainage gap, and the gravel entering the drainage gap can flow into the inner cavity along the stacking plates under the action of gravity. 2. The high-efficiency shallow sand settling tank according to claim 1 is characterized in that the sand-water separation assembly also includes a support frame, and the stacking plates and the flow stabilizing part are fixedly connected to the support frame. 3. The high-efficiency shallow sand settling tank according to claim 1 is characterized in that the flow stabilizing portion is vertically arranged, the flow stabilizing portion includes a shell, the inner cavity is located in the shell and passes through the upper and lower ends of the shell, and the stacking plates are arranged on one side or two opposite sides of the shell. 4. The high-efficiency shallow sand settling tank according to claim 1 is characterized in that, among all the stacked plates located on the same side of the flow stabilizing portion, the stacked plates are arranged at intervals along the height direction of the flow stabilizing portion. 5. The high-efficiency shallow sand settling tank according to claim 1 is characterized in that the inlet flow equalizing section includes a first ramp, a second ramp and a third ramp connected in sequence from top to bottom, and the inclination angle between the second ramp and the horizontal plane is greater than the inclination angle between the first ramp and the horizontal plane, and greater than the inclination angle between the third ramp and the horizontal plane. 6. The high-efficiency shallow grit settling tank according to claim 1 is characterized in that the high-efficiency shallow grit settling tank also includes a sand discharge component and a sand washing component, and the sand discharge component is located below the inner cavity and is used to transport the settled sand and gravel to the sand washing component for cleaning. 7. The high-efficiency shallow sand settling tank according to claim 6 is characterized in that the sand discharge component includes a screw and a spiral blade, the screw is rotatably arranged, the spiral blade is fixed on the screw, and the spiral blade can transport sand and gravel to the sand washing component when the screw rotates. 8. The high-efficiency shallow grit chamber according to claim 1 is characterized in that the high-efficiency shallow grit chamber further comprises an aeration pipe, wherein the aeration pipe is located above the inlet flow equalizing portion and is used to inject fine bubbles into the oily wastewater to be treated. 9. The high-efficiency shallow grit settling tank according to claim 1 is characterized in that the high-efficiency shallow grit settling tank also includes a skimming part, the skimming part is located above the sand-water separation component, the skimming part is a tank body structure, and can use flotation to skim off the oil phase and scum. 10. The high-efficiency shallow sand settling tank according to claim 1 is characterized in that an overflow weir plate is provided on the tank body, the overflow weir plate is located at the water outlet side of the sand-water separation component, and a water outlet is provided on the overflow weir plate.