Polluted plot foundation pit heavy metal-containing wastewater treatment device

Abstract

The utility model discloses a heavy metal-containing wastewater treatment device for a foundation pit of a polluted plot. The device comprises a wastewater collection tank, a water treatment assembly and a clean water tank, the water treatment assembly comprises an adjusting tank, an oxidation treatment tank group, a sludge sedimentation tank and a clear water disinfection tank. The sludge settling tank comprises a tank body, a central stirring shaft pipe, a stirring spiral blade, a clear water outlet cover and a stirring driving part. The wastewater collection pool is provided with a front separation unit, and the front separation unit comprises a separation box body, a central partition plate, a plurality of longitudinal flow separation plates, an overhead filter screen, a collection liquid inlet pipe, a separation liquid outlet pipe and a separation sludge outlet pipe. According to the utility model, the process of'coagulating sedimentation + advanced oxidation + coagulating sedimentation 'is adopted to treat the foundation pit wastewater, part of garbage, impurities and soil in the foundation pit wastewater are pre-separated through the pre-separation unit, and the centrifugal separation unit is arranged in the water treatment assembly to carry out rapid solid-liquid separation on the wastewater subjected to advanced oxidation and coagulation treatment, so that the water treatment efficiency is improved. The precipitation efficiency is improved, and the overall treatment capacity is ensured.

Description

TECHNICAL FIELD

[0001] The utility model relates to wastewater treatment technical field, concretely is a kind of polluted land block foundation pit heavy metal-containing wastewater treatment device. BACKGROUND

[0002] The main sources of foundation pit wastewater include precipitation, soil seepage water, construction area washing water, etc. If there is soil or groundwater pollution in the construction site, the foundation pit wastewater may also contain heavy metal pollution. The applicant arranged 32 soil points and 12 groundwater monitoring wells in a new city project plot in Guangdong. The test results showed that, except for hexavalent chromium, the other 8 heavy metals and inorganic substances in the samples were detected to varying degrees. In addition, the soil pollution remediation wastewater generated during the pretreatment of contaminated soil (such as washing wastewater of the sieve residue) may also flow into the foundation pit, so that the foundation pit wastewater contains pollutants such as heavy metals, which need to be treated before being discharged.

[0003] During the treatment of foundation pit wastewater, the following problems are encountered: the content of garbage, impurities and soil in the foundation pit wastewater is relatively high, and after being delivered to the collection tank by the water pump, the overall sedimentation efficiency is low. In addition, a large amount of flocculent components may be generated in the wastewater after treatment of pollutants such as heavy metals, and the natural sedimentation efficiency is also low, so that the size of the sedimentation tank in the treatment device is large. SUMMARY

[0004] The utility model aims at providing a kind of polluted land block foundation pit heavy metal-containing wastewater treatment device to solve the problems in the prior art.

[0005] To achieve the above-mentioned purpose, the technical scheme of the utility model provides a kind of polluted land block foundation pit heavy metal-containing wastewater treatment device, including wastewater collection tank, water treatment assembly, clean water tank;Water treatment assembly includes adjusting tank, oxidation treatment tank group, sludge sedimentation tank, clean water sterilization tank.

[0006] Further, the sludge sedimentation tank includes a tank body, a central stirring shaft pipe, a clean water outlet cover, and a stirring driving member. The tank body is a hollow cavity structure with an upper inlet pipe and a lower outlet pipe connected to the oxidation treatment tank group. A central stirring shaft pipe is arranged in the center of the tank body and is rotatably connected to the tank body. The upper part of the central stirring shaft pipe extends out of the tank body and is connected to the stirring driving member. Stirring helical blades are arranged on the outer side of the central stirring shaft pipe. The central stirring shaft pipe is rotatably connected to the clean water outlet pipe through the tank body. A blind hole is arranged in the central stirring shaft pipe and is connected to the clean water outlet pipe. A clean water outlet cover is arranged on the central stirring shaft pipe above the blind hole. The clean water outlet cover is semispherical in shape, hollow, and has an opening downward with a bottom edge lower than the blind hole.

[0007] Further, the sludge settling tank further comprises a longitudinal laminar flow plate; the longitudinal laminar flow plate is arranged on the inner wall of the tank body below the stirring spiral blade.

[0008] Further, the sludge settling tank further comprises a liquid distribution plate; the liquid distribution plate is arranged below the liquid inlet pipe and fixedly connected with the inner wall of the tank body, and is arranged in an inclined manner, with the height of one side below the liquid inlet pipe being higher; the liquid distribution plate is provided with arrayed through grooves, and a through hole is arranged in the center of the liquid distribution plate for the central stirring shaft pipe to pass through.

[0009] Further, gaps are arranged between adjacent through grooves of the same row of the liquid distribution plate, and adjacent rows of the through grooves are arranged in a staggered manner; on the side of the liquid distribution plate with a lower height, a notch is arranged.

[0010] Further, the wastewater collection tank is further provided with a pre-separation unit; the pre-separation unit comprises a separation box body, a central partition plate, a plurality of longitudinal partition plates, an overhead filter screen, a collection liquid inlet pipe, a separation liquid outlet pipe and a separation sludge outlet pipe; the separation box body is a hollow box structure, and the central partition plate is arranged in the separation box body to divide the separation box body into two chambers, i.e., a filtering chamber and a sedimentation chamber; the height of the central partition plate is lower than the height of the separation box body; the collection liquid inlet pipe is arranged on the side wall of the separation box body in the filtering chamber; the overhead filter screen is arranged on the upper part of the separation box body and fixedly connected with the top of the central partition plate; the separation sludge outlet pipe is arranged on the bottom of the side wall of the sedimentation chamber close to the central partition plate; and the separation liquid outlet pipe is arranged on the side wall of the sedimentation chamber parallel to the central partition plate.

[0011] Further, a plurality of longitudinal partition plates are arranged in the sedimentation chamber; the longitudinal partition plates are arranged in parallel with the central partition plate 2, fixedly connected with the separation box body on both sides, and have a height lower than that of the central partition plate; gaps are arranged between the bottom of the longitudinal partition plates and the bottom of the inner wall of the box body; and the height of the separation liquid outlet pipe is lower than that of the longitudinal partition plates.

[0012] Further, the bottom surface of the separation box body is arranged in an inclined manner, and the height of the side close to the collection liquid inlet pipe is lower.

[0013] Further, an openable and closable cleaning window and a floating overflow port are arranged on the side wall of the separation box body in the filtering chamber region; and the lowest part of the floating overflow port is higher than the highest part of the central partition plate.

[0014] Further, an overflow window is arranged on the overhead filter screen in the filtering chamber region; and the height of the overflow window is between the height of the floating overflow port and the height of the highest part of the central partition plate.

[0015] The utility model provides a kind of polluted land block foundation pit heavy metal-containing wastewater treatment device, using the process of "coagulation sedimentation+advanced oxidation+coagulation sedimentation" to treat foundation pit wastewater, after treatment reaches standard, it is discharged to municipal sewage pipe network, on specific structure, there is front separation unit in collection tank, can carry out front separation to part of rubbish, impurities, soil in foundation pit wastewater, avoid its into collection tank, can improve the sedimentation efficiency of collection tank to some extent, reduce the use amount of coagulant and other medicines, there is centrifugal separation unit in water treatment assembly, can carry out quick solid-liquid separation to wastewater after advanced oxidation and coagulation treatment, improve sedimentation efficiency, ensure overall processing capacity. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is the whole scheme schematic diagram of the utility model.

[0017] Figure 2 It is a kind of embodiment site plan of the utility model.

[0018] Figure 3 It is the sludge sedimentation tank schematic diagram of a kind of embodiment of the utility model.

[0019] Figure 4 It is the sludge sedimentation tank section view schematic diagram of a kind of embodiment of the utility model.

[0020] Figure 5 It is the front separation unit schematic diagram of a kind of embodiment of the utility model.

[0021] Figure 6 It is the front separation unit perspective schematic diagram of a kind of embodiment of the utility model.

[0022] Figure 7 It is the sludge sedimentation tank liquid distribution plate schematic diagram of a kind of embodiment of the utility model. DETAILED DESCRIPTION

[0023] The technical scheme in the embodiments of the utility model will be described clearly and completely in conjunction with the drawings in the embodiments of the utility model, obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without making creative labor belong to the scope of protection of the utility model.

[0024] As shown in accompanying Figure 1 , 2 The utility model relates to a kind of polluted land block foundation pit heavy metal-containing wastewater treatment device, including wastewater collection tank 1, water treatment assembly 2, clear water tank 3.

[0025] Specifically, as shown in accompanying Figure 2As shown, the applicant sets up a wastewater collection pool (18m x 12m x 1.5m) for a new city project in Guangdong, a set of 20m3 / h integrated water treatment assembly (treatment system), two support pool type clean water pools (20m x 35m x 1.5m), and the total processing capacity of the equipment is recommended to be 20m3 / h, and the maximum daily processing capacity is 480m 3 . It meets the processing requirements of the maximum pumping capacity of the foundation pit (222m 3 / d) and the surface rainwater yield (29m 3 / d) of the project area. The data detection cycle of the wastewater is about 3 days, the maximum pumping capacity of the foundation pit is 222m 3 / d, and the surface rainwater yield is 29m 3 / d. Each detection cycle requires water storage of 753m 3 . This project sets up two clean water pools for alternating detection by environmental supervision, and the size of the clean water pool is 20m x 35m x 1.5m, and the maximum volume is about 1000m 3 . It can meet the needs of environmental supervision monitoring.

[0026] Specifically, the applicant uses the "coagulation sedimentation + advanced oxidation + coagulation sedimentation" process in the wastewater treatment of the project, and discharges the treated wastewater to the municipal sewage pipe network, wherein the bottom mud of the collection pool 1 is disposed as contaminated soil, and the bottom mud of the water treatment assembly 2 is disposed as hazardous waste by entrusting a professional agency.

[0027] The water treatment assembly 2 includes a conditioning tank 21, an oxidation treatment tank group 22, a sludge sedimentation tank 23, and a clean water disinfection tank 24. The oxidation treatment tank group 22 includes a high-level oxidation treatment process for heavy metals and other pollutants. The conditioning tank 21, the oxidation treatment tank group 22, and the clean water disinfection tank 24 are selected from existing mature products, and the specific structure is not within the scope of protection of the present application.

[0028] As shown in Figs. Figure 3 , 4 7, after the wastewater is treated by the oxidation treatment tank group 22 and coagulation agents are added, a large amount of flocculent components are generated, and the sedimentation efficiency is low. Therefore, in order to improve the sedimentation efficiency, the applicant improves the sludge sedimentation tank 23. The sludge sedimentation tank 23 includes a tank body 231, a central stirring shaft pipe 232, stirring spiral blades 233, longitudinal laminar plates 234, a clean water outlet cover 235, and a stirring driving member 236.

[0029] The tank body 231 is a hollow cavity structure, and the upper part is provided with a liquid inlet pipe 2311 which is in communication with the oxidation treatment tank group 22. The lower part is provided with a sludge outlet pipe 2312 and a clean water outlet pipe 2313. The sludge outlet pipe 2312 is connected to the oxidation treatment tank group 22 through a valve to realize sludge backflow, and can also be connected to other tank bodies.

[0030] A central stirring shaft pipe 232 is arranged in the center of the tank body 231 and is rotatably connected to the tank body 231 through a bearing structure. The upper part of the central stirring shaft pipe 232 extends out of the tank body 231 and is connected to a stirring driving member 236. The stirring driving member 236 is an electric motor.

[0031] A liquid distribution plate b is arranged at the lower part of the liquid inlet pipe 2311 and is fixedly connected to the inner wall of the tank body 231. The liquid distribution plate b is arranged obliquely and has a higher height on one side below the liquid inlet pipe 2311. The liquid distribution plate b is provided with arrayed through grooves b1. Gaps are arranged between adjacent through grooves in the same row. Adjacent rows of through grooves are arranged staggeredly. Through the staggered arrangement of the through grooves, the water flowing from the liquid inlet pipe 2311 flows along the liquid distribution plate b downward and flows into the tank body 1. In order to avoid blockage, the size of the through grooves is relatively large. Meanwhile, a gap is arranged on the side of the liquid distribution plate b with a lower height. The liquid distribution plate b is provided with a through hole in the center for the central stirring shaft pipe 232 to pass through.

[0032] A stirring spiral blade 233 is arranged at the middle and upper part of the outer side of the central stirring shaft pipe 232.

[0033] The central stirring shaft pipe 232 passes through the tank body 231 and is rotatably connected to a clean water outlet pipe 2313. The rotating connecting member is a commercially available product. The central stirring shaft pipe 232 is provided with a blind hole 232a coaxial with the axis thereof. The bottom of the blind hole 232a is in communication with the clean water outlet pipe 2313. The side wall of the central stirring shaft pipe 232 is provided with a through hole 232b at the top of the blind hole 232a. The through hole 232b is in communication with the blind hole 232a. A clean water outlet cover 235 is arranged on the central stirring shaft pipe 232 above the through hole 232b. The clean water outlet cover 235 is semispherical, hollow and has an opening downward. The bottom edge of the clean water outlet cover 235 is lower than the through hole 232b.

[0034] A plurality of longitudinal laminar flow plates 234 are arranged on the inner wall of the tank body 231 below the stirring spiral blade 233. The longitudinal laminar flow plates 234 are parallel to the axis of the central stirring shaft pipe 232.

[0035] The wastewater enters the tank body 231 through the liquid inlet pipe 2311 and forms a spiral flow under the driving of the central stirring shaft pipe 232 and the stirring spiral blade 233. During the spiral flow, the heavier flocculation components in the wastewater move outward to the inner wall of the tank body 231, and the clean water is located in the central area. The clean water in the central area flows out through the through hole 232b-blind hole 232a-clean water outlet pipe 2313. The clean water outlet cover 235 prevents the wastewater from flowing out directly through the through hole 232b. The arrangement of the longitudinal laminar flow plates 234 can effectively reduce the overall disturbance of the water flow at the bottom of the tank body, which is conducive to accelerating the sedimentation process.

[0036] As shown in the accompanying drawings Figure 5、 6 As shown in the wastewater collection tank 1 is further provided with a pre-separation unit 11, the pre-separation unit 11 includes a separation box 111, a central partition 112, a plurality of longitudinal baffles 113, a top filter screen 114, a collection inlet pipe 115, a separation outlet pipe 116, a separation sludge pipe 117.

[0037] The separation box 111 is a hollow box structure, which is internally provided with a central partition 112, which separates the separation box 111 into two chambers, respectively, a filter chamber c1 and a sedimentation chamber c2, and the height of the central partition 112 is lower than the height of the separation box 111.

[0038] The collection inlet pipe 115 is arranged on the side wall of the separation box 111 in the filter chamber c1, and a cleanable window c3 and a floating overflow port c4 are further arranged on the side wall of the separation box 111 in the filter chamber c1 area, and the lowest part of the floating overflow port c4 is higher than the highest part of the central partition 112.

[0039] The top filter screen 114 is arranged on the upper part of the separation box 111, and the middle part is fixedly connected with the top of the central partition 112, and the overflow window 1141 is arranged on the top filter screen 114 in the filter chamber c1 area, and the height of the overflow window 1141 is between the highest part of the floating overflow port c4 and the central partition 112, which is used as overflow when the garbage blocks the filter screen.

[0040] A plurality of longitudinal baffles 113 are arranged in the sedimentation chamber c2, the longitudinal baffles 113 are arranged in parallel with the central partition 112, and the two sides are fixedly connected with the separation box 111, and the height is lower than that of the central partition 112, and the bottom is provided with a gap with the inner wall bottom of the box 111, and the separation sludge pipe 117 is arranged on the bottom of the side wall of the central partition 112 in the sedimentation chamber c2, and the separation outlet pipe 116 is arranged on the side wall parallel to the central partition 112 in the sedimentation chamber c2, and the height of the separation outlet pipe 116 is lower than that of the longitudinal baffles 113.

[0041] The bottom surface of the separation box 111 is arranged to be inclined, and the height of the side close to the collection inlet pipe 115 is lower.

[0042] The wastewater flowing from the collection inlet pipe 115 enters the filter chamber c1, and after being filtered by the top filter screen 114, it overflows to the sedimentation chamber c2, and the longitudinal baffles 113 can reduce the turbulence of the wastewater in the sedimentation chamber c2, and the heavier stones and sand are preliminarily settled, and then the cleaner wastewater flows into the wastewater collection tank 1 through the separation outlet pipe 116.

[0043] It should be noted that unless specifically stated and limited otherwise, the terms "mounting", "connecting", "connecting", "fixing", "setting" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

Claims

1. A device for treating heavy metal-containing wastewater from a contaminated site's foundation pit, characterized in that, The sewage collection tank, water treatment assembly, clean water tank; the water treatment assembly comprises an adjusting tank, an oxidation treatment tank group, a sludge sedimentation tank and a clean water sterilization tank; the sludge sedimentation tank comprises a tank body, a central stirring shaft pipe, a clean water outlet cover, and a stirring driving part; the tank body is a cavity structure with an inner cavity, an upper part of the tank body is provided with an inlet pipe, and the inlet pipe is communicated with the oxidation treatment tank group; a lower part of the tank body is provided with a sludge outlet pipe and a clean water outlet pipe; a central stirring shaft pipe is arranged in the center of the tank body and is rotatably connected with the tank body; an upper part of the central stirring shaft pipe extends out of the tank body and is connected with the stirring driving part; stirring spiral blades are arranged on the outer side of the central stirring shaft pipe; the central stirring shaft pipe penetrates through the tank body and is rotatably connected with the clean water outlet pipe; a blind hole is arranged in the central stirring shaft pipe and coincides with the axis of the central stirring shaft pipe; the bottom of the blind hole is communicated with the clean water outlet pipe; a through hole is arranged in the side wall of the central stirring shaft pipe and communicated with the blind hole; a clean water outlet cover is arranged on the central stirring shaft pipe above the through hole; the clean water outlet cover is in a semispherical shape, has an inner cavity, and is open downward; the bottom edge of the clean water outlet cover is lower than the through hole; the sewage collection tank is further provided with a pre-separation unit; the pre-separation unit comprises a separation box, a central partition plate, a plurality of longitudinal partition plates, a top filter screen, a collection inlet pipe, a separation outlet pipe and a separation sludge outlet pipe; the separation box is a box structure with an inner cavity; the central partition plate is arranged in the separation box and divides the separation box into two chambers, i.e., a filtering chamber and a sedimentation chamber; the height of the central partition plate is lower than the height of the separation box; the collection inlet pipe is arranged on the side wall of the separation box in the filtering chamber; the top filter screen is arranged on the upper part of the separation box and is fixedly connected with the top of the central partition plate; the separation sludge outlet pipe is arranged on the side wall of the sedimentation chamber near the bottom of the central partition plate; and the separation outlet pipe is arranged on the side wall of the sedimentation chamber parallel to the central partition plate.

2. The device for treating wastewater containing heavy metals from a foundation pit of a contaminated site according to claim 1, characterized in that, The sludge sedimentation tank further comprises a longitudinal laminar flow plate; the longitudinal laminar flow plate is arranged on the inner wall of the tank body below the stirring spiral blades.

3. The device for treating wastewater containing heavy metals in a foundation pit of a contaminated site according to claim 1, characterized in that, The sludge sedimentation tank further comprises a liquid distribution plate; the liquid distribution plate is arranged on the lower part of the inlet pipe and is fixedly connected with the inner wall of the tank body; the liquid distribution plate is arranged in an inclined manner; the height of one side below the inlet pipe is higher; a plurality of through grooves are arranged on the liquid distribution plate in an arrayed manner; and a through hole is arranged in the center of the liquid distribution plate for the central stirring shaft pipe to pass through.

4. The device for treating wastewater containing heavy metals in a foundation pit of a contaminated site according to claim 3, characterized by Gaps are arranged between adjacent through grooves in the same row of the liquid distribution plate; adjacent rows of through grooves are arranged in a staggered manner; a notch is arranged on the side with a lower height of the liquid distribution plate.

5. The device for treating wastewater containing heavy metals in a foundation pit of a contaminated site according to claim 1, characterized in that, A plurality of longitudinal partition plates are arranged in the sedimentation chamber; the longitudinal partition plates are arranged in parallel to the central partition plate 2; the longitudinal partition plates are fixedly connected with the separation box on both sides; the height of the longitudinal partition plates is lower than that of the central partition plate; and a gap is arranged between the bottom of the longitudinal partition plates and the inner wall of the box; the height of the separation outlet pipe is lower than that of the longitudinal partition plates.

6. The device for treating wastewater containing heavy metals in a foundation pit of a contaminated site according to claim 1, characterized in that, The bottom surface of the separation box is arranged in an inclined manner; the height of one side near the collection inlet pipe is lower.

7. The device for treating wastewater containing heavy metals in a foundation pit of a contaminated site according to claim 1, characterized in that, An openable and closable cleaning window and a floating overflow port are further arranged on the side wall of the separation box in the filtering chamber region; the lowest part of the floating overflow port is higher than the highest part of the central partition plate.

8. The device for treating wastewater containing heavy metals from a foundation pit of a contaminated site according to claim 7, characterized by An overflow window is arranged on the top filter screen in the filtering chamber region; the height of the overflow window is between the height of the floating overflow port and the highest part of the central partition plate.

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