Mixing station sewage treatment device

Abstract

The utility model discloses a sewage treatment device for a mixing station. The sewage treatment device comprises an adjusting tank, integrated skid-mounted equipment and a sludge tank, the adjusting tank communicates with a collecting pipeline; the output end of the adjusting tank is communicated with the integrated skid-mounted equipment; in the integrated skid-mounted equipment, a coagulation reaction tank is communicated with a high-density sedimentation tank, sewage in the coagulation reaction tank enters the high-density sedimentation tank, supernate overflows to a pH regulating tank through an effluent overflow weir, the pH regulating tank is communicated with a multi-medium filter, the multi-medium filter is communicated with a clear water disinfection tank, and the bottom of a sludge collecting hopper is communicated with a sludge tank through a sludge pipeline. Meanwhile, the bottom of the sludge collecting hopper is also connected back to the coagulation reaction tank through a pipeline. The technical problems that a conventional sewage treatment mode of a mixing station is insufficient in treatment depth and low in treatment efficiency are solved, and the sewage treatment device of the mixing station is provided, a high-density precipitation mode is used, the sewage treatment efficiency is improved, the filter pressing sewage amount is reduced, part of sludge is recycled, and sewage deep treatment and standard recycling are achieved.

Description

Technical Field

[0001] The utility model relates to the field of wastewater treatment in batching plants, and specifically relates to a sewage treatment device for batching plants. Background Art

[0002] The wastewater treatment in batching plants is affected by various factors. Optimizing the wastewater treatment device in batching plants can achieve environmental protection, economy and normal production of batching plants. The sewage treatment device of the project batching plant needs to consider factors such as regional location, topography, geomorphology, geology, climate, hydrology, transportation and surrounding human environment, explore the sewage treatment method adapted to local conditions, ensure the recycling of wastewater in batching plants, protect the water environment, save water resources, and achieve the effects of economy and energy conservation.

[0003] The sewage in concrete mixing plants is roughly divided into two categories; one is slightly polluted sewage, mainly including the ground flushing in non-mixing production areas, rainwater, etc. This kind of sewage mainly contains suspended substances such as sediment; the other is heavily polluted sewage, mainly including the cleaning sewage of equipment in the mixing area and transport tank trucks, which contains a large amount of suspended substances, has a high pH value and a high hardness (Ca 2+ , and there is no discharge requirement, but it is easy to block the water supply pipeline or dust suppression nozzle during reuse);

[0004] During the wastewater treatment process in highway engineering batching plants, the conventional treatment process of sand and gravel separator + filter press + five-stage sedimentation tank is usually adopted. This method has a large amount of wastewater treated by filter press, and does not effectively reduce indexes such as pH value and hardness (Ca 2+ ). There is a problem of secondary slight pollution during the reuse process. All wastewater is treated by filter press, and the filter press process lasts for a long time and the treatment efficiency is low. Some use sand and gravel separator + filter press + carbon dioxide neutralization device + five-stage sedimentation tank, which has the problem of safety management risk of pressure vessels. Content of the Utility Model

[0005] Therefore, in order to solve the above deficiencies, the utility model provides a sewage treatment device for batching plants here, which mainly solves the problems such as excessive suspended solids, too high pH value, and high hardness (Ca 2+ , Mg 2+ ) in the heavily polluted wastewater of batching plants, and achieves the effect of meeting the standard of sewage treatment and recycling. The technical problem solved by this application is the problem of insufficient treatment depth and low treatment efficiency in the conventional sewage treatment method of batching plants. The purpose is to provide a sewage treatment device for batching plants, which uses the high-density sedimentation method to improve the sewage treatment efficiency, reduce the amount of filter-pressed sewage, recycle part of the sludge, and achieve the deep treatment and up-to-standard reuse of sewage.

[0006] The utility model is implemented as follows. A sewage treatment device for batching plants is constructed, and its characteristics are as follows;

[0007] The device includes an adjustment tank, an integrated skid-mounted equipment, and a sludge tank;

[0008] The regulating tank is connected to the collection pipeline, enabling the slightly polluted sewage and highly polluted sewage from the mixing station to flow into the regulating tank through the collection pipeline and be evenly mixed therein; the output end of the regulating tank is connected to the integrated skid-mounted equipment;

[0009] The integrated skid-mounted equipment includes a coagulation reaction tank, a high-density sedimentation tank, a pH adjustment tank, a multi-media filter, and a clean water disinfection tank; the coagulation reaction tank is connected to the high-density sedimentation tank, and the sewage in the coagulation reaction tank enters the high-density sedimentation tank. In the high-density sedimentation tank, large flocs formed by suspended solids in the sewage settle at the bottom sludge hopper of the sludge tank, and the supernatant overflows to the pH adjustment tank through the effluent overflow weir; in the pH adjustment tank, while the pH of the sewage reaches the standard, excess oxalate ions are removed. The pH adjustment tank is connected to the multi-media filter, and in the multi-media filter, the suspended solids in the sewage are further filtered out. The multi-media filter is connected to the clean water disinfection tank. The bottom of the sludge hopper is connected to the sludge tank through a sludge pipeline, and at the same time, the bottom of the sludge hopper is also connected back to the coagulation reaction tank through a pipeline.

[0010] Furthermore; it also includes a ferric sulfate dosing device and a PAM dosing device, and the ferric sulfate dosing device and the PAM dosing device are respectively connected to the coagulation reaction tank.

[0011] Furthermore; the pH adjustment tank is connected to an oxalic acid dosing device.

[0012] Furthermore; the clean water disinfection tank is connected to the ferric sulfate dosing device and the sodium hypochlorite dosing device.

[0013] Furthermore; the integrated skid-mounted equipment has a walkway plate, and a staircase is arranged at the walkway plate.

[0014] Furthermore; the coagulation reaction tank and the high-density sedimentation tank are integrally located in the left area of the corresponding platform of the integrated skid-mounted equipment, the pH adjustment tank and the clean water disinfection tank are integrally located in the middle area of the corresponding platform of the integrated skid-mounted equipment, and the multi-media filter, the ferric sulfate dosing device, the PAM dosing device, the oxalic acid dosing device, and the sodium hypochlorite dosing device are located in the right area of the corresponding platform of the integrated skid-mounted equipment.

[0015] Furthermore; a pH detector is arranged in the pH adjustment tank, and the dosage of oxalic acid and ferric sulfate is controlled by detecting the pH value of the sewage in the tank.

[0016] Furthermore; a residual chlorine detector is arranged in the clean water disinfection tank, which is used for automatically adding sodium hypochlorite disinfectant and then used for reusing the reclaimed water.

[0017] The utility model has the following advantages: 1. The pH neutralization medicaments selected are ferric sulfate and oxalic acid. Only one dry medicament needs to be added to this bunker every day. The equipment automatically intakes water to configure the drug concentration and then automatically doses it into the sewage tank, and there is no safety risk of pressure vessels.

[0018] 2. The system as a whole meets the requirements of the first-class standard of the Comprehensive Wastewater Discharge Standard (GB8978 - 1996).

[0019] 3. Compared with the traditional filter press filtration process, the operation of the filter press requires a high degree of manual intervention. And to achieve continuity in the sewage treatment process, multiple filter presses need to be used alternately. Its performance in dealing with continuous large-scale sewage discharge during peak periods is not as good as this process.

[0020] 4. The vertical design of the system sewage is reasonable, and one-time lifting is adopted to avoid head loss; each chemical dosing system accurately measures and adds chemicals according to the instrument feedback signals of the sewage treatment system, reducing the energy consumption of the system operation.

[0021] 5. The clear water disinfection tank is equipped with a pH meter, residual chlorine meter, flow meter, etc. to monitor the effluent data in real time. If the effluent does not meet the standard, the system automatically adjusts the chemical dosing amount and stops the water inlet at the same time. The sewage at the back end of the integrated skid-mounted equipment flows back to the equipment inlet end for circular treatment until the effluent data meets the standard. Brief Description of the Drawings

[0022] Figure 1 is the overall implementation structure diagram of this application;

[0023] Figure 2 is the layout plan of the integrated skid-mounted equipment of this application.

[0024] Among them: regulating tank 1, coagulation reaction tank 2, high-density sedimentation tank 3, pH adjustment tank 4, multi-media filter 5, clear water disinfection tank 6, sludge tank 7, ferric sulfate dosing device 8, PAM dosing device, sodium hypochlorite dosing device 10, oxalic acid dosing device 11. Detailed Embodiment

[0025] The following will be combined with the attached Figure 1 - Figure 2 This utility model will be described in detail. The technical solutions in the embodiments of this utility model will be described clearly and completely. Obviously, the described embodiments are only a part of the embodiments of this utility model, rather than all the embodiments. Based on the embodiments in this utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this utility model.

[0026] This utility model provides a sewage treatment device for a mixing plant here, as Figure 1 - Figure 2 shown, and it can be implemented in the following manner;

[0027] This device includes a regulating tank 1, an integrated skid-mounted equipment, and a sludge tank 7;

[0028] The regulating tank 1 is connected to the collection pipeline, enabling the slightly polluted sewage and severely polluted sewage from the mixing plant to flow into the regulating tank through the collection pipeline and be evenly mixed within the regulating tank 1; the output end of the regulating tank 1 is connected to the integrated skid-mounted equipment;

[0029] The integrated skid-mounted equipment includes a coagulation reaction tank 2, a high-density sedimentation tank 3, a pH adjustment tank 4, a multi-media filter 5, and a clean water disinfection tank 6; the coagulation reaction tank 2 is connected to the high-density sedimentation tank 3, and the sewage in the coagulation reaction tank 2 enters the high-density sedimentation tank 3. In the high-density sedimentation tank 3, large flocs formed by suspended solids in the sewage settle at the bottom sludge hopper of the sludge tank, and the supernatant overflows to the pH adjustment tank 4 through the effluent overflow weir; in the pH adjustment tank 4, while the pH of the sewage reaches the standard, excess oxalate ions are removed. The pH adjustment tank 4 is connected to the multi-media filter 5, and in the multi-media filter 5, suspended solids in the sewage are further filtered out. The multi-media filter 5 is connected to the clean water disinfection tank 6. The bottom of the sludge hopper is connected to the sludge tank 7 through a sludge pipeline, and at the same time, the bottom of the sludge hopper is also connected back to the coagulation reaction tank 2 through a pipeline.

[0030] In this application, it also includes a ferric sulfate dosing device 8 and a PAM dosing device 9, and the ferric sulfate dosing device 8 and the PAM dosing device 9 are respectively connected to the coagulation reaction tank 2.

[0031] In this application, the pH adjustment tank 4 is connected to an oxalic acid dosing device 11.

[0032] In this application, the clean water disinfection tank 6 is connected to a ferric sulfate dosing device and a sodium hypochlorite dosing device 10.

[0033] In this application, the integrated skid-mounted equipment has a walkway board, and a staircase is provided at the walkway board.

[0034] In this application, the coagulation reaction tank 2 and the high-density sedimentation tank 3 are integrally located in the left area of the corresponding platform of the integrated skid-mounted equipment, the pH adjustment tank 4 and the clean water disinfection tank 6 are integrally located in the middle area of the corresponding platform of the integrated skid-mounted equipment, and the multi-media filter 5, the ferric sulfate dosing device, the PAM dosing device, the oxalic acid dosing device, and the sodium hypochlorite dosing device are located in the right area of the corresponding platform of the integrated skid-mounted equipment.

[0035] In this application, a pH detector is provided in the pH adjustment tank 4 to control the dosage of oxalic acid and ferric sulfate by detecting the pH value of the sewage in the tank.

[0036] In this application, a residual chlorine detector is provided in the clean water disinfection tank 6 for automatically adding sodium hypochlorite disinfectant for reusing the reclaimed water.

[0037] The operating principle of this application will be described in detail below;

[0038] SS (Suspended Solids): This pollution factor refers to the insoluble pollutants in sewage. Conventional treatment methods include air flotation, sedimentation, and filtration. For suspended solids with a density lower than that of sewage, air flotation is generally used; for those with a density higher than that of sewage, sedimentation is used; the filtration method can be applied to both cases above, but filtration consumes more power. Generally, it is used under the conditions of higher effluent standards and lower suspended solid concentrations in line with the principles of environmental protection, low carbon, energy conservation, and emission reduction.

[0039] Combined with the characteristics of the sewage from the mixing plant, the sedimentation process for removing suspended solids is selected as the high-density sedimentation tank process in the sedimentation method, and the coagulant is Fe2(SO4)3. The cation Fe in the selected reagent 3+ After forming Fe(OH)3↓, the formed flocs can attract the suspended solids in the sewage to form larger flocs, which is convenient for better sedimentation of the suspended solids and improves the sedimentation efficiency. At the same time, Fe 3+ can combine with OH in the sewage - to reduce the pH value of the sewage; the anion SO4 in the reagent 2- can react with Ca in the sewage 2+ to form gypsum precipitation (CaSO4↓), which not only removes Ca in the sewage 2+ but also reduces the hardness of the sewage without introducing too many sulfate ions into the sewage.

[0040] For the recycled part of the sewage treatment process, the multi-media filtration process in the filtration method is used, and the filtration medium is a mixed graded filter material of quartz sand and activated carbon.

[0041] pH: This index mainly limits the acidity and alkalinity of the sewage. The pH of the sewage from the mixing plant is generally above 10, with strong alkalinity. The adjustment of pH is generally carried out by using reagents for neutralization. Conventional reagents include hydrochloric acid, sulfuric acid, oxalic acid, or carbonic acid (aqueous solution of CO2), etc. The principle for selecting the pH adjustment reagent this time is not to introduce new pollutants. Since hydrochloric acid and sulfuric acid are controlled drugs, they are generally not used; CO2 requires high-pressure containers for storage with high safety requirements, and the usage occasions are easily limited. Therefore, oxalic acid is selected for pH adjustment. At the same time, combined with the reagent Fe2(SO4)3 in the SS (suspended solids) removal process section, the oxalate ions introduced can be reduced during pH neutralization, effectively preventing the exceeding of CODcr standard.

[0042] First, add ferric sulfate for coagulation and sedimentation: Fe 3+ + 3OH- → Fe(OH)3↓ (1)

[0043] Ca 2+ + SO4 2- → CaSO4↓ (2)

[0044] If the pH is not reduced below 9, add a small amount of oxalic acid for adjustment:

[0045] H2C2O4 + 2OH - →H2O + C2O4 2- (3)

[0046] Add a small amount of ferric sulfate to remove oxalate ions:

[0047] 2Fe 3+ + 3C2O4 2- →Fe2(C2O4)2↓ (4)

[0048] Description of the integrated sewage treatment process: Slightly polluted sewage and heavily polluted sewage from the mixing station flow into the regulation tank through the collection pipeline and are evenly mixed in the regulation tank; then the sewage enters the coagulation reaction tank of the integrated skid-mounted equipment. First, add ferric sulfate and PAM to coagulate the sewage, and at the same time remove part of the OH - Adjust the pH, and the dosing amount is automatically adjusted by the feedback signal of the sewage flow rate entering the system; then the sewage enters the high-density sedimentation tank. In the high-density sedimentation tank, large flocs formed by suspended solids in the sewage precipitate at the bottom sludge hopper of the sludge tank, and the supernatant overflows to the pH adjustment tank through the effluent overflow weir; a pH detector is set in the pH adjustment tank, and the dosing amounts of oxalic acid and ferric sulfate are controlled by detecting the pH value of the sewage in the tank to ensure that the sewage pH meets the standard while removing excess oxalate ions and preventing the over-standard discharge of CODcr caused by excessive oxalate ions in the sewage; then the sewage enters the multi-media filter to further filter and remove suspended solids in the sewage; then the sewage enters the clean water disinfection tank. If the sewage is reused, sodium hypochlorite disinfectant is automatically added through the residual chlorine detector set in the clean water disinfection tank and then used as reclaimed water. The sludge generated by the system mainly contains calcium sulfate, ferric oxalate, calcium oxalate, and concrete components, etc., which can be dewatered and transported out for disposal or resource utilization.

[0049] This patent has the following advantages and beneficial effects:

[0050] 1. Ferric sulfate and oxalic acid are selected as the pH neutralization agents. Only one dry powder agent needs to be added to this silo every day. The equipment automatically intakes water to configure the drug concentration and then automatically doses it into the sewage tank, and there is no safety risk of pressure vessels.

[0051] 2. The overall system meets the requirements of the first-class standard of the Comprehensive Sewage Discharge Standard (GB8978-1996).

[0052] 3. Compared with the traditional filter press filtration process, the operation of the filter press requires a high degree of manual intervention, and multiple filter presses need to be used alternately to achieve continuity in the sewage treatment process. Its performance is not as good as this process when dealing with continuous large-scale sewage discharge during peak periods.

[0053] 4. The vertical design of the system sewage is reasonable, and a one-time lift is adopted to avoid head loss; each dosing system accurately measures and adds drugs according to the instrument feedback signal of the sewage treatment system, reducing the energy consumption of the system operation.

[0054] 5. The clear water disinfection tank is equipped with a pH meter, residual chlorine meter, flow meter, etc. to monitor the effluent data in real time. If the effluent does not meet the standard, the system automatically adjusts the dosing amount and stops the water inlet at the same time. The sewage at the back end of the integrated skid-mounted equipment flows back to the water inlet end of the equipment for cyclic treatment until the effluent data meets the standard.

[0055] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A sewage treatment device for a mixing station, characterized in that ； The device includes an adjustment tank (1), an integrated skid-mounted equipment, and a sludge tank (7); The adjustment tank (1) is connected to a collection pipeline, enabling the slightly polluted sewage and highly polluted sewage from the mixing station to flow into the adjustment tank through the collection pipeline and be evenly mixed in the adjustment tank (1); the output end of the adjustment tank (1) is connected to the integrated skid-mounted equipment; The integrated skid-mounted equipment includes a coagulation reaction tank (2), a high-density sedimentation tank (3), a pH adjustment tank (4), a multi-media filter (5), and a clean water disinfection tank (6); the coagulation reaction tank (2) is connected to the high-density sedimentation tank (3), and the sewage in the coagulation reaction tank (2) enters the high-density sedimentation tank (3). In the high-density sedimentation tank (3), large flocs formed by suspended solids in the sewage settle at the bottom sludge hopper of the sludge tank, and the supernatant overflows to the pH adjustment tank (4) through the effluent overflow weir; while the pH of the sewage reaches the standard in the pH adjustment tank (4), excess oxalate ions are removed. The pH adjustment tank (4) is connected to the multi-media filter (5), and the suspended solids in the sewage are further filtered out in the multi-media filter (5). The multi-media filter (5) is connected to the clean water disinfection tank (6). The bottom of the sludge hopper is connected to the sludge tank (7) through a sludge pipeline, and at the same time, the bottom of the sludge hopper is also connected back to the coagulation reaction tank (2) through a pipeline.

2. The sewage treatment device for a batching plant according to claim 1, wherein; It also includes a ferric sulfate dosing device (8) and a PAM dosing device (9), and the ferric sulfate dosing device (8) and the PAM dosing device (9) are respectively connected to the coagulation reaction tank (2).

3. The sewage treatment device for a mixing plant according to claim 1, characterized in that; The pH adjustment tank (4) is connected to an oxalic acid dosing device (11).

4. The sewage treatment device for a mixing station according to claim 1, wherein; The clean water disinfection tank (6) is connected to the ferric sulfate dosing device (8) and a sodium hypochlorite dosing device (10).

5. The sewage treatment device for a batching plant according to claim 1, wherein; The integrated skid-mounted equipment has a walkway board, and a staircase is set at the walkway board.

6. The sewage treatment device for a mixing plant according to claim 1, wherein; The coagulation reaction tank (2) and the high-density sedimentation tank (3) are entirely located in the left area of the corresponding platform of the integrated skid-mounted equipment, the pH adjustment tank (4) and the clean water disinfection tank (6) are entirely located in the middle area of the corresponding platform of the integrated skid-mounted equipment, and the multi-media filter (5), the ferric sulfate dosing device (8), the PAM dosing device (9), the oxalic acid dosing device (11), and the sodium hypochlorite dosing device (10) are located in the right area of the corresponding platform of the integrated skid-mounted equipment.

7. The sewage treatment device for a batching plant according to claim 1, characterized in that; A pH detector is set in the pH adjustment tank (4) to control the dosing amounts of oxalic acid and ferric sulfate by detecting the pH value of the sewage in the tank.

8. The sewage treatment device for a batching plant according to claim 1, wherein; A residual chlorine detector is set in the clean water disinfection tank (6) for automatically dosing sodium hypochlorite disinfectant for reusing the reclaimed water.

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