Background
The challenges of sewage decentralized treatment practices in some rural residences, tourist attractions, farmhouse happiness and other scenes include strong fluctuation of inlet water quality and water quantity, nitrogen and phosphorus removal and treatment of excess sludge. In practice, in order to solve the contradiction between the low carbon-nitrogen ratio of the inlet water and the carbon source demand of nitrogen and phosphorus removal, the external carbon source becomes a common coping manner. In order to improve the dephosphorization efficiency, many projects add a coagulating sedimentation unit in the decentralized sewage treatment. These approaches not only increase economic costs, but also increase the workload of operation and maintenance. The single project of decentralized sewage treatment produces a small amount of sludge, usually a centralized treatment mode after collection is adopted, and the collection and transportation increase the operation cost. The sludge side-stream hydrolysis or sludge side-stream hydrolysis technology carries out supernatant fluid reflux of partial residual sludge hydrolysis, which can supplement carbon source, reduce sludge discharge capacity, improve phosphorus removal efficiency and improve effluent quality. The technology is not widely applied at present and is mainly applied to municipal sewage treatment plants.
The aforementioned rural residences, tourist attractions, farmhouse happiness and the like have the characteristics that the fluctuation of the quality and the quantity of the sewage in the longitudinal time of each project is high, and the sewage is compared with each other in the transverse direction, so that sewage treatment process equipment is required to have not only impact load resistance but also certain process flow regulation capacity. Most of distributed domestic sewage treatment process equipment solidifies a certain process flow, can only adjust partial parameters such as flow, aeration quantity, reflux quantity and the like, and does not have the adjusting capacity of the process flow.
Disclosure of Invention
The invention provides a multi-point water inlet sleeve type inversion A2An O + MBBR integrated sewage treatment device solves the problem that the sewage treatment efficiency is low because the rural sewage does not have the process flow regulation capability at present.
The technical scheme for realizing the invention is as follows:
the invention is in A2After adding a pre-anoxic section before the O process, the process flow has two anoxic sections, the pre-anoxic section becomes the first anoxic section, A2The anoxic zone in O becomes the second anoxic zone. In A2The O process reflows the mixed liquid at the tail end of the aeration tank to the first anoxic section, and reflows the mixed liquid at the middle section of the aeration tank to the second anoxic section to form a nested inverted A2And (4) O process.
In order to improve the biomass, the anti-impact load capacity and the treatment capacity of the reactor, all biological reaction tanks are filled with suspended fillers to form a Moving Bed Biofilm Reactor (MBBR), and the filling ratio is 30-50%. The whole process of the filling moving bed biological membrane process adopts a cellular baffling type, which is beneficial to forming an adaptive biological membrane at each section and improving the treatment efficiency.
In particular, a multipoint water inlet sleeve type inversion A2O + MBBR integration sewage treatment plant includes the raw water inlet tube, includes first oxygen deficiency device, first anaerobism device, second oxygen deficiency device and good oxygen device in proper order, good oxygen device links to each other with the sediment device, and the sediment device links to each other with mud hydrolysis unit, the raw water inlet tube links to each other with first oxygen deficiency device, first anaerobism device, second oxygen deficiency device and good oxygen device respectively.
And a sludge return pipe is arranged on the sedimentation device and communicated with the first anoxic device.
The aerobic device comprises a first aerobic device, a second aerobic device and a third aerobic device, wherein the first aerobic device is respectively provided with a first return mixing pipe, the first return mixing pipe is communicated with the first anoxic device, and the first aerobic device is also connected with the sedimentation device.
The aerobic section keeps the filler fluidized by aeration, a perforated pipe is adopted for aeration, and a stirrer is arranged at the non-aeration section to keep the filler fluidized.
And a second backflow mixing pipe is arranged on the second aerobic device and communicated with the second anoxic device.
And a hydrolysis return pipe is arranged on the sludge hydrolysis device and is connected with the first aerobic device.
The first anoxic section has raw water in 30%, reflux mixed liquid in reflux ratio of 100-200%, sludge reflux in reflux ratio of 20-50% and hydrolysis supernatant in 10-50%, and obvious denitrification effect. The existence of the first anoxic section is also beneficial to keeping the oxidation-reduction potential of the anaerobic section at a low value, and the treatment stability of the anaerobic section is improved.
The first anaerobic section has low oxidation-reduction potential, and partial raw water (about 10 percent) enters the first anaerobic section, so that the phosphorus accumulating bacteria have better phosphorus release performance in the first anaerobic section.
The second anoxic section has partial raw water (about 40 percent) and reflux mixed liquid (100-; the second anaerobic stage continues to release phosphorus.
Part of raw water (about 0-20%) enters the first half section of the aerobic section, dissolved oxygen is kept at 1-1.5mg/L, and denitrification and organic matter degradation are simultaneously carried out under the action of suspended sludge and a biological membrane. The dissolved oxygen of the second half section of the aerobic section is kept at 2-2.5mg/L, the organic matter is continuously degraded, and the remaining ammonia nitrogen is nitrified.
The sedimentation tank adopts an inclined tube for sedimentation.
The sludge hydrolysis tank adopts vertical flow sedimentation. The sludge hydrolysis tank has the following functions: sludge reduction; secondly, the sludge hydrolysis supernatant flows back to the pre-anoxic section, so that carbon sources required by denitrification can be effectively supplemented, and the nitrogen and phosphorus removal effect is improved; and the sludge storage tank has the effect of sludge storage, the excess sludge is intermittently discharged from the sludge hydrolysis tank, the treatment effect of the main flow process is not influenced, and the sludge discharge period can be effectively prolonged.
The realization of multiple spot is intake, sets up the point of intaking in four positions such as first anoxic zone, first anaerobism section, second anoxic zone and aerobic section front end. The opening and closing of the four water inlet valves and the flow regulation, and the opening and closing of the two mixed liquid reflux pumps can enable the first anoxic section, the first anaerobic section and the second anoxic section to be switched among anaerobic/anoxic states, and the adaptive fine adjustment of the process flow is realized.
The reasonable plane arrangement of the process flow greatly reduces the use amount of the pipeline of the integrated equipment, and the whole layout is compact and reasonable.
The process equipment can realize good CODcrTotal nitrogen, ammonia nitrogen and total phosphorus are removed, and the sludge production amount is small. Realizes the COD of the effluent under the condition of the conventional domestic sewage inflowcrLess than 50mg/L, total nitrogen less than 15 mg/L, ammonia nitrogen less than 5mg/L, and total phosphorus less than 0.5 mg/L.
The invention has the beneficial effects that: the invention organically integrates sludge side-stream hydrolysis and inversion A based on the dispersed sewage treatment requirement2O, MBBR, etc., and optimizing unit layout, provides a multi-point water inlet side stream hydrolysis nested inversion A for distributed sewage treatment2An O + MBBR technology and an integrated device, specifically a nested inversion A with multi-point water inflow2The O + MBBR is a main biological treatment process, effluent passes through an inclined tube precipitation unit, supernatant effluent is system effluent, partial sludge in the inclined tube precipitation unit directly flows back to the main biological treatment process, partial sludge enters a lateral flow hydrolysis unit, and lateral flow hydrolysis supernatant flows back to the main biological treatment process. The process and the equipment have good effects of removing organic matters, removing nitrogen and phosphorus, have strong adaptability to the change of the water inlet load and produce small amount of sludge.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without inventive effort based on the embodiments of the present invention, are within the scope of the present invention.
As shown in FIG. 1, the present invention is shown at A2After adding a pre-anoxic section before the O process, the process flow has two anoxic sections, the pre-anoxic section becomes the first anoxic section, A2The anoxic zone in O becomes the second anoxic zone. In A2The O process reflows the mixed liquid at the tail end of the aeration tank to the first anoxic section, and reflows the mixed liquid at the middle section of the aeration tank to the second anoxic section to form a nested inverted A2And (4) O process.
As shown in fig. 2, the multiple water inlet sleeve type inversion A2O + MBBR integration sewage treatment plant, including raw water inlet tube 12, include first oxygen deficiency device 1, first anaerobism device 2, second oxygen deficiency device 3 and aerobic apparatus in proper order, aerobic apparatus links to each other with precipitation device 4, and precipitation device 4 links to each other with sludge hydrolysis device 5, the raw water inlet tube links to each other with first oxygen deficiency device 1, first anaerobism device 2, second oxygen deficiency device 3 and aerobic apparatus respectively.
And a sludge return pipe is arranged on the sedimentation device 4 and communicated with the first oxygen-poor device 1.
The aerobic device comprises a first aerobic device 6, a second aerobic device 7 and a third aerobic device 8, the first aerobic device 6 is respectively provided with a first return mixing pipe 9, the first return mixing pipe 9 is communicated with the first anoxic device 1, and the first aerobic device 6 is also connected with the sedimentation device 4.
And a second backflow mixing pipe 10 is arranged on the second aerobic device 7, and the second backflow mixing pipe 10 is communicated with the second anoxic device 3.
The sludge hydrolysis device 5 is provided with a hydrolysis return pipe 11, and the hydrolysis return pipe 11 is connected with the first aerobic device 6.
The first anoxic device 1 has raw water (about 30 percent) inlet, reflux mixed liquor (reflux ratio 100-.
The first aerobic device 6 has partial raw water (about 0-20%) entering, the dissolved oxygen is kept at 1-1.5mg/L, and the dissolved oxygen of the third aerobic device 6 is kept at 2-2.5 mg/L.
Preferably, the sedimentation tank adopts an inclined tube for sedimentation.
The sludge hydrolysis tank adopts vertical flow sedimentation. The sludge hydrolysis tank has the following functions: sludge reduction; secondly, the sludge hydrolysis supernatant flows back to the pre-anoxic section, so that carbon sources required by denitrification can be effectively supplemented, and the nitrogen and phosphorus removal effect is improved; and the sludge storage tank has the effect of sludge storage, the excess sludge is intermittently discharged from the sludge hydrolysis tank, the treatment effect of the main flow process is not influenced, and the sludge discharge period can be effectively prolonged.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.