CN209906566U - IV-type water discharge standard domestic sewage treatment device - Google Patents
IV-type water discharge standard domestic sewage treatment device Download PDFInfo
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- CN209906566U CN209906566U CN201920394145.2U CN201920394145U CN209906566U CN 209906566 U CN209906566 U CN 209906566U CN 201920394145 U CN201920394145 U CN 201920394145U CN 209906566 U CN209906566 U CN 209906566U
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Abstract
The utility model discloses a domestic sewage treatment device with standard IV-class water discharge, which comprises a contact anoxic tank, a contact aerobic tank, a dephosphorization sedimentation tank, an anoxic filter tank and a sedimentation filter tank which are communicated in an overflow manner in sequence; the bottom parts of the contact anoxic tank and the contact aerobic tank are respectively provided with an aeration device externally connected with a fan; the contact anoxic tank, the contact aerobic tank, the anoxic filter tank and the aerobic filter tank are filled with fillers; an electrolytic bath is arranged in the contact aerobic tank, an electrode is arranged in the electrolytic bath and is connected with a power supply. The device of the utility model produces less mud, and the total nitrogen of the effluent reaches the IV-class water standard; the hydraulic impact resistance effect is good, and the effluent is stable and clear; the management is simple, the maintenance is convenient, and the device is suitable for rural domestic sewage treatment; the electrolytic phosphorus removal is adopted, the effect is good, and the total phosphorus in the effluent reaches the IV-class water standard.
Description
Technical Field
The utility model relates to a sewage treatment technical field, concretely relates to standard sewage treatment unit is discharged to IV class water.
Background
With the improvement of the quality of life, the environmental protection requirement is also improved, the discharge amount of the domestic sewage is increasingly increased, and the treatment of the rural domestic sewage becomes important. Because rural domestic sewage has the characteristics of large change of water quality and water quantity, high concentration of ammonia nitrogen and total phosphorus and low water temperature, the prior art has many defects.
The patent application document of the invention in China with the application number of 201410316054.9 discloses a novel tail water upgrading system, which comprises a first biological activity reaction tank, an anoxic denitrification tank, a second biological activity reaction tank, a coagulating sedimentation tank, a photocatalysis and advanced oxidation device, an activation reaction tank, a natural release tank, a mechanical filter and an activated carbon filter, wherein the mechanical filter and the activated carbon filter are used for removing SS (suspended substances) in water and adsorbing COD (chemical oxygen demand). The system has high greening rate and good denitrification effect, but the coagulation reaction tank needs to be added with a coagulant, so that the medicament cost is increased, and meanwhile, the dephosphorization effect is slightly poor. The Chinese patent application with the application number of 201810645796.4 discloses a low-energy consumption synchronous nitrosation denitrification sewage upgrading process and equipment, and inlet water sequentially passes through a nitrosation reaction zone and a denitrification reaction zone in a reaction tank body. The system has good denitrification effect and small occupied area, but the requirement on phosphorus in the effluent quality is difficult to meet the requirements of class IV water bodies in the environmental quality Standard of surface Water (GB 3838-2002). The patent application document with the application number of 201520309370.3 discloses a novel tail water upgrading treatment system, which comprises a coarse grating tank, a fine grating tank, a grit chamber, a biochemical reaction tank, a secondary sedimentation tank, an intermediate water tank and a disinfection water outlet tank which are sequentially connected, wherein an aeration biological filter, a high-efficiency sedimentation tank and the like are sequentially communicated between the intermediate water tank and the disinfection tank. However, the system is complex, occupies a large area, and has medicament cost.
Disclosure of Invention
An object of the utility model is to provide a domestic sewage treatment system makes the play water stably reach "surface water environmental quality standard" (GB3838-2002) IV class water requirement, and the treatment effect is good, and the running cost is low, compares AO technology, on the basis that does not increase whole equipment size and dwell time, through simple and easy lobe setting, realizes that the play water reaches IV class water.
A kind of IV water discharges the standard domestic sewage treatment plant, including contacting the anoxic tank, contacting the aerobic tank, dephosphorizing the sedimentation tank, anoxic filter and aerobic filter that communicate sequentially; the bottoms of the contact anoxic tank, the contact aerobic tank, the anoxic filter tank and the aerobic filter tank are provided with aeration devices externally connected with fans; the contact anoxic tank, the contact aerobic tank, the anoxic filter tank and the aerobic filter tank are filled with fillers; and the contact aerobic tank is internally provided with a plate electrode which is connected with a power supply.
Preferably, the contact aerobic tank, the dephosphorization sedimentation tank and the anoxic filter tank are communicated in sequence in an overflow manner; the anoxic filter tank is communicated with the aerobic filter tank at the bottom.
Preferably, the device also comprises a regulating reservoir positioned at the front end, and the contact anoxic reservoir is connected with the regulating reservoir through a lift pump.
Preferably, the aeration devices in the contact anoxic tank and the anoxic filter tank adopt perforated aeration pipes; and the aeration devices in the contact aerobic tank and the aerobic filter tank adopt microporous aeration pipes.
Preferably, a first reflux pump is arranged at the bottom of the contact aerobic pool, and a pipeline of the reflux pump is connected to the contact anoxic pool; a second reflux pump is arranged at the bottom of the dephosphorization sedimentation tank, and a pipeline of the reflux pump is connected to the contact anoxic tank; and a third reflux pump is arranged at the bottom of the aerobic filter tank, and a pipeline of the reflux pump is connected into the anoxic filter tank.
Preferably, the volume ratio of the contact anoxic tank to the contact aerobic tank to the box bodies of the dephosphorization sedimentation tank, the contact aerobic tank to the box bodies of the anoxic filter and the aerobic filter is 1: 2-5: 1-3: 1 to 2.
Preferably, the filler in the contact anoxic tank and the contact aerobic tank is one or more of elastic filler, pall ring and polyhedral hollow spheres; the filler in the anoxic filter tank and the aerobic filter tank is one or more of fiber bundle filler, polyurethane filler and fiber balls.
The elastic filler can improve the sludge concentration, and simultaneously can not be blocked by a small amount of materialized sludge generated by electrolytic phosphorus removal, and further preferably, the elastic filler is preferably selected as the filler in both the contact anoxic tank and the contact aerobic tank.
The polyurethane filler is used for fully absorbing free sludge of the system, so that the effluent is clear without precipitation, and the polyurethane filler is preferably used in the anoxic filter tank and the aerobic filter tank.
The device comprises a carbon source box, a carbon source adding pipeline and a chemical feeding device, wherein the outlet of the carbon source adding pipeline is connected to the anoxic filter tank. A part of carbon source can be added into the anoxic filter tank, and the carbon source comprises but is not limited to one or more of excrement water, methanol, flour and glucose. The fecal water is economical and effective and is easy to purchase or collect.
Preferably, the electrode plate is an aluminum electrode, and the power supply is a direct current power supply.
Preferably, the reflux ratio of the mixed liquor 1 is 150-250%, the reflux ratio of the mixed liquor 2 at the bottom of the sedimentation tank is 30-600%, the reflux ratio is too high, and a large amount of reflux oxygen-carrying mixed liquor to the contact anoxic tank can damage the environment of the contact anoxic tank; the reflux ratio is too low, and the effluent nitro and nitroso are difficult to reach the standard.
More preferably, the reflux ratio of the mixed solution 1 is 200% and the reflux ratio of the mixed solution 2 is 50%.
Preferably, the current required by the electrolytic phosphorus removal device is I ═ Q ═ CTN0.7-0.15A, and the voltage is 2.5-3.5V. Too low a current may result in poor treatment; the current is too high, which causes the loss of the aluminum electrode to be aggravated and waste.
More preferably, the current I ═ Q ═ C is usedTN0.1) a, the operating voltage of the power supply is 3V.
The device of the utility model comprises a contact anoxic tank, a contact aerobic tank, a sedimentation tank, an anoxic filter tank and an aerobic filter tank which are connected in sequence, wherein the contact anoxic tank is connected with a lift pump, the bottom of the contact anoxic tank is provided with a perforated aeration pipe, and filler is added into the tank; filling materials are added into the contact aerobic pool, a microporous aeration disc is arranged at the bottom of the pool, a reflux pump is arranged at the bottom of the pool, and a pipeline of the reflux pump is connected with the contact anoxic pool; an electrolytic cell is arranged in the contact aerobic cell, an aluminum electrode is arranged in the electrolytic cell, and the aluminum electrode is connected with a direct-current power supply; a reflux pump is arranged in the sedimentation tank, the bottom sludge partially reflows to the contact anoxic tank through the reflux pump, and partial sludge is discharged; adding filler and part of carbon source into the anoxic filter tank; and (4) adding filler into the aerobic filter.
Compared with the prior art today, the utility model discloses following beneficial effect has:
(1) the device of the invention produces less mud, and the total nitrogen of the effluent reaches the IV-class water standard;
(2) the device has good hydraulic shock resistance effect, and the effluent is stable and clear;
(3) the device is simple to manage and convenient to maintain, and is suitable for rural domestic sewage treatment;
(4) the device provided by the invention adopts electrolytic phosphorus removal, the effect is good, and the total phosphorus in the effluent reaches the IV-class water standard.
Drawings
Fig. 1 is a schematic structural diagram of the present invention.
The reference numerals shown in the figures are as follows:
1-adjusting tank 2-lifting pump 3-sludge tank
4-contact anoxic tank 5-contact aerobic tank 6-dephosphorization sedimentation tank
7-anoxic filter 8-aerobic filter 9-aeration device
10-electrode plate 11-reflux pump 12-equipment room
13-blower 14-carbon source box
Detailed Description
As shown in figure 1, the standard domestic sewage treatment device for IV-class water discharge comprises a regulating tank 1 at the front end, and a contact anoxic tank 4, a contact aerobic tank 5, a dephosphorization sedimentation tank 6, an anoxic filter tank 7 and an aerobic filter tank 8 which are sequentially communicated.
Contact oxygen deficiency pond and contact aerobic tank are in the bottom intercommunication, contact aerobic tank, dephosphorization sedimentation tank and the oxygen deficiency filtering pond overflow intercommunication in proper order between, oxygen deficiency filtering pond and aerobic tank are connected in the bottom, the equalizing basin bottom sets up elevator pump 2, in the pipeline access contact oxygen deficiency pond of elevator pump, the mud of equalizing basin passes through sludge impoundment 3 regular discharge, contact oxygen deficiency pond, contact aerobic tank, oxygen deficiency filtering pond and aerobic tank bottom all set up aeration equipment 9.
Filling filler in the contact anoxic tank, and arranging a perforated aeration pipe at the bottom of the tank; filling filler in the contact aerobic tank, arranging a microporous aeration disc at the bottom of the tank, arranging a first reflux pump above the microporous aeration disc, connecting a pipeline of the first reflux pump into the contact anoxic tank, and refluxing part of mixed liquor; an electrolytic bath is arranged in the contact aerobic tank, an aluminum electrode is arranged in the electrolytic bath, and the aluminum electrode is connected with a direct current power supply. The perforated aeration pipe and the microporous aeration disc are both connected with a fan 13.
The dephosphorization sedimentation tank is a conventional sedimentation tank and is used for sedimentation and sedimentation, a second reflux pump is arranged at the bottom of the dephosphorization sedimentation tank, and a pipeline of the second reflux pump is connected into the contact anoxic tank to carry out partial sludge reflux.
The bottom in oxygen deficiency filtering pond and good oxygen filtering pond all sets up aeration equipment, and aeration equipment adopts the perforation aeration pipe in the oxygen deficiency filtering pond, and aeration equipment adopts micropore aeration dish in the good oxygen filtering pond, and perforation aeration pipe and micropore aeration dish all connect the fan. The anoxic filter tank and the aerobic filter tank are filled with fillers.
An equipment room 12 is also arranged, a fan is arranged in the equipment room, a carbon source box 14 is also arranged in the equipment room, one end of a carbon source pipeline is connected with the carbon source box, and the other end of the carbon source pipeline is connected into the anoxic filter tank.
The filler contacting the anoxic tank and the aerobic tank comprises one or more of elastic filler, pall rings and polyhedral hollow balls. The elastic filler can improve the sludge concentration and can not be blocked by a small amount of materialized sludge generated by electrolytic phosphorus removal. Still more preferably an elastomeric filler. The filler of the anoxic filter tank and the aerobic filter tank comprises one or more of but not limited to fiber bundle filler, polyurethane filler and fiber balls. The polyurethane filler is used for fully absorbing free sludge of the system, so that effluent is clear and does not need to be precipitated; further preferred is a polyurethane filler.
The process flow is as follows:
firstly, sewage enters a regulating tank through self-flowing, the sewage enters a contact anoxic tank through a lifting pump, microorganisms decompose macromolecular organic matters into micromolecular organic matters, denitrifying bacteria use the organic matters in the sewage as carbon sources, and a large amount of NO brought in a backflow mixed liquid3 --N and NO2 -Reduction of-N to N2Released into the air to reduce the total nitrogen and BOD of the effluent5Decrease in concentration, NO3 -A substantial decrease in N concentration; the effluent enters a contact aerobic tank, and part of the mud-water mixture flows back to a contact anoxic tank through a reflux pump; the electrolytic dephosphorization device in the contact aerobic tank utilizes the electrolysis principle, the anode adopts an aluminum electrode, corresponding aluminum ions and PO are generated by electrolysis4 3-Precipitation, or with electrolytically generated OH-Forming a precipitate to adsorb phosphorus in the sewage so as to achieve the aim of removing the phosphorus in the water; the mud-water mixture enters a sedimentation tank for solid-liquid separation, the bottom mud partially flows back to the contact anoxic tank through a reflux pump, and part of the bottom mud is discharged; the supernatant enters an anoxic filter tank, and part of carbon source is correspondingly added to provide energy for denitrifying bacteria and enhance the denitrification of system microorganisms; supernatant fluid flows into the aerobic filter from the anoxic filter; and filtering the effluent of the aerobic filter, and discharging the effluent after reaching the standard.
Example 1
The residence time of the contact anoxic tank is 1h, the residence time of the contact aerobic tank is 3h, the residence time of the anoxic filter tank is 1h, and the residence time of the aerobic filter tank is 1 h. Elastic filler is added into the contact anoxic tank, polyurethane filler is added into the anoxic filter tank, the filling rate of the filler in the tank is 30%, and the reflux ratio of the mixed liquid is 100% and 200% respectively. The results of the treatment are shown in Table 1:
TABLE 1
| Index of water quality | Inflow water | Discharging water |
| TN | ≤40mg/L | ≤1.5mg/L |
| NH3-N | ≤20mg/L | ≤1.5mg/L |
| TP | ≤5mg/L | ≤0.3mg/L |
| SS | ≤150mg/L | ≤5mg/L |
Example 2
The residence time of the contact anoxic tank is 2 hours, the residence time of the contact aerobic tank is 4 hours, the residence time of the anoxic filter tank is 2 hours, and the residence time of the aerobic filter tank is 2 hours. Elastic filler is added into the contact anoxic tank, polyurethane filler is added into the anoxic filter tank, the filling rate of the filler in the tank is 30%, and the reflux ratio of the mixed liquid is 100% and 200% respectively. The results of the treatment are shown in Table 2:
TABLE 2
Comparative example 1
Adopts the traditional AAO sewage treatment process. The residence time of the anaerobic tank is 1h, the residence time of the anoxic tank is 2h, and the residence time of the aerobic tank is 7 h. The sludge reflux ratio is 80%. The results of the treatment are shown in Table 3:
TABLE 3
| Index of water quality | Inflow water | Discharging water |
| TN | ≤80mg/L | ≤30mg/L |
| NH3-N | ≤30mg/L | ≤8mg/L |
| TP | ≤10mg/L | ≤5mg/L |
| SS | ≤150mg/L | ≤30mg/L |
Comparative example 2
The residence time of the contact anoxic tank is 2 hours, the residence time of the contact aerobic tank is 4 hours, the residence time of the anoxic filter tank is 2 hours, and the residence time of the aerobic filter tank is 2 hours. The first-stage treatment is to add elastic filler into the contact tank, wherein the filling rate of the filler in the tank is 30 percent, and the reflux ratio of the mixed liquid is 200 percent respectively. The results of the treatment are shown in Table 4:
TABLE 4
| Index of water quality | Inflow water | Discharging water |
| TN | ≤80mg/L | ≤8mg/L |
| NH3-N | ≤30mg/L | ≤5mg/L |
| TP | ≤10mg/L | ≤0.3mg/L |
| SS | ≤150mg/L | ≤30mg/L |
Comparative example 3
The sewage treatment process disclosed by the invention is adopted. The residence time of the anoxic tank is 2 hours, the residence time of the aerobic tank is 4 hours, the residence time of the anoxic filter tank is 2 hours, and the residence time of the aerobic filter tank is 2 hours. The results are shown in Table 5:
TABLE 5
| Index of water quality | Inflow water | Discharging water |
| TN | ≤80mg/L | ≤20mg/L |
| NH3-N | ≤30mg/L | ≤8mg/L |
| TP | ≤10mg/L | ≤0.3mg/L |
| SS | ≤150mg/L | ≤15mg/L |
The above description is only the specific embodiments of the present invention, but the technical features of the present invention are not limited thereto, and any person skilled in the relevant art can also make changes or modifications within the scope of the present invention.
Claims (9)
1. A kind of IV water discharges the standard domestic sewage treatment plant, characterized by, including contacting the anoxic tank, contacting the aerobic tank, dephosphorizing the sedimentation tank, anoxic filter and aerobic filter that communicate sequentially; the bottoms of the contact anoxic tank, the contact aerobic tank, the anoxic filter tank and the aerobic filter tank are provided with aeration devices externally connected with fans; the contact anoxic tank, the contact aerobic tank, the anoxic filter tank and the aerobic filter tank are filled with fillers; and the contact aerobic tank is internally provided with a plate electrode which is connected with a power supply.
2. The domestic sewage treatment device according to claim 1, wherein said contact anoxic tank is in communication with said contact aerobic tank at the bottom, and said contact aerobic tank, dephosphorization sedimentation tank and anoxic filter tank are in overflow communication in sequence; the anoxic filter tank is communicated with the aerobic filter tank at the bottom.
3. The domestic sewage treatment device according to claim 1, further comprising a conditioning tank located at the front end, wherein said contact anoxic tank is connected to said conditioning tank by a lift pump.
4. The domestic sewage treatment apparatus according to claim 1, wherein said aeration means in said contact anoxic tank and anoxic filter tank employs perforated aeration pipes; and the aeration devices in the contact aerobic tank and the aerobic filter tank adopt microporous aeration pipes.
5. The domestic sewage treatment device according to claim 1, wherein a first reflux pump is arranged at the bottom of the contact aerobic tank, and a pipeline of the reflux pump is connected to the contact anoxic tank; and a second reflux pump is arranged at the bottom of the dephosphorization sedimentation tank, and a pipeline of the reflux pump is connected to the contact anoxic tank.
6. The domestic sewage treatment device according to claim 1, wherein the tank body volume ratio of the contact anoxic tank, the contact aerobic tank, the dephosphorization sedimentation tank, the anoxic filter tank and the aerobic filter tank is 1: 2-5: 1-3: 1 to 2.
7. The domestic sewage treatment device according to claim 1, wherein the filler in the contact anoxic tank and the contact aerobic tank is one or more of elastic filler, pall ring and polyhedral hollow sphere; the filler in the anoxic filter tank and the aerobic filter tank is one or more of fiber bundle filler, polyurethane filler and fiber balls.
8. The domestic sewage treatment apparatus according to claim 1, wherein said electrode plate is an aluminum electrode, and said power source is a dc power source.
9. The domestic sewage treatment device according to claim 1, further comprising a dosing device, wherein the dosing device comprises a carbon source tank and a carbon source adding pipeline, and an outlet of the carbon source adding pipeline is connected to the anoxic filter tank.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111170462A (en) * | 2020-03-16 | 2020-05-19 | 南京大学 | Alternate starvation micro-aerobic anaerobic coupling filler sludge side flow in-situ reduction strengthening process |
| CN111268799A (en) * | 2020-03-03 | 2020-06-12 | 南京大学 | Efficient biological treatment system and process for organic nitrogen industrial wastewater |
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2019
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111268799A (en) * | 2020-03-03 | 2020-06-12 | 南京大学 | Efficient biological treatment system and process for organic nitrogen industrial wastewater |
| CN111268799B (en) * | 2020-03-03 | 2021-04-27 | 南京大学 | Efficient biological treatment system and process for organic nitrogen industrial wastewater |
| CN111170462A (en) * | 2020-03-16 | 2020-05-19 | 南京大学 | Alternate starvation micro-aerobic anaerobic coupling filler sludge side flow in-situ reduction strengthening process |
| CN111170462B (en) * | 2020-03-16 | 2021-05-28 | 南京大学 | Alternate starvation micro-aerobic anaerobic coupling filler sludge side flow in-situ reduction strengthening process |
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