Construction method of continuous flow short-cut denitrification biological membrane module with short hydraulic retention time and construction treatment device based on construction method

Abstract

The invention provides a construction method of a continuous flow short-cut denitrification biological membrane module with short hydraulic retention time and a construction treatment device based on the continuous flow short-cut denitrification biological membrane module, and relates to the technical field of biological sewage treatment. According to the construction method, short-cut denitrification floc sludge is quickly started in an SBR (sequencing batch reactor) by adopting anoxic starvation treatment, then biofilm culturing treatment is performed, and finally, a short-cut denitrification biofilm is put into a continuous flow reactor, so that the construction of the continuous flow short-cut denitrification biofilm module with short hydraulic retention time is realized. The construction time and the reaction time of the short-cut denitrification biological membrane module are greatly shortened, and meanwhile, the continuous flow treatment mode also solves the problems that the nitrite concentration is gradually reduced after reaching a peak value in one period in the periodic operation of the SBR reactor in short-cut denitrification, and the nitrite concentration is reduced along with the shortening of the reaction period. The problems of low nitrite accumulation rate, complex operation, difficult regulation and control and the like caused by gradually advanced occurrence time of a nitrite peak value are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of sewage biological treatment, and particularly relates to a construction method of a continuous-flow short-cut denitrification biofilm module with a short hydraulic retention time and a construction treatment device based thereon. Background Art

[0002] In recent years, the country has attached great importance to the water pollution problem, and the government has improved the sewage treatment efficiency by building and upgrading sewage treatment plants. At present, most sewage treatment plants still adopt the traditional biological nitrogen removal process. However, with the increasingly complex water quality components of the influent and the continuous improvement of the national policy requirements for the effluent water quality, the traditional nitrogen removal process can no longer meet the existing discharge requirements, and there is an urgent need to develop a more economical and efficient sewage nitrogen removal technology to solve the environmental pollution problem caused by nitrogen.

[0003] Anaerobic ammonium oxidation is a new sewage treatment technology, which can directly convert ammonia nitrogen and nitrite into nitrogen gas under the action of anaerobic ammonium oxidation bacteria, greatly improving the nitrogen removal efficiency. However, how to obtain stable nitrite nitrogen remains a major problem. In the actual operation process of the short-cut nitrification process, it is greatly affected by the fluctuation of domestic sewage water quality. Artificially regulating the water temperature will increase the extremely high treatment cost, and the regulation of DO and PH has instability, which restricts the practical application of the short-cut nitrification / anaerobic ammonium oxidation system.

[0004] In recent years, there have been many reports on the combined process of short-cut denitrification and Anammox (biofilm nitrogen removal process). However, the existing methods to start the short-cut denitrification system only by reducing the carbon-nitrogen ratio, increasing the pH value, etc. require a long time, generally nearly a month or even longer.

[0005] In addition, it has been found in recent studies that when starting short-cut denitrification in an SBR reactor, the nitrite concentration reaches a peak when nitrate is exhausted, but as the reaction time extends, the nitrite concentration will further decrease. Although this situation can be avoided by stopping the reaction in time or shortening the reaction time, as the reaction time is shortened, the reaction process will speed up accordingly. Moreover, when using an SBR, the pump must be started and stopped frequently, and the valves must also be opened and closed frequently, increasing the complexity of the operation.

[0006] Therefore, it is very necessary and urgent to study and construct a continuous-flow short-cut denitrification biofilm module with a short hydraulic retention time to shorten the construction time and reaction time of the short-cut denitrification biofilm module, and to alleviate the problems such as low nitrite accumulation rate, complex operation, and difficult regulation caused by the gradually advancing appearance time of the nitrite peak in the periodic operation of the existing short-cut denitrification in an SBR reactor.

[0007] In view of this, the present invention is specifically proposed. Summary of the Invention

[0008] The object of the present invention is to provide a construction method for a continuous-flow short-cut denitrification biofilm module with a short hydraulic retention time. This construction method greatly shortens the construction time and reaction time of the short-cut denitrification biofilm module, and solves the problems such as low nitrite accumulation rate, complex operation, and difficult regulation caused by the gradual decrease of nitrite concentration after reaching the peak value within one cycle in the SBR reactor during the periodic operation of short-cut denitrification, and the gradual advance of the appearance time of the nitrite peak with the shortening of the reaction cycle.

[0009] In order to achieve the above object of the present invention, the following technical solutions are specifically adopted:

[0010] A construction method for a continuous-flow short-cut denitrification biofilm module with a short hydraulic retention time provided by the present invention, the construction method comprising:

[0011] (A) Initiation of SBR short-cut denitrification:

[0012] Inoculate the excess sludge from the secondary sedimentation tank or the activated sludge from the biochemical tank of the sewage treatment plant into the anoxic SBR reactor to make the sludge concentration in the reactor 2000 - 3000 mg / L. Subsequently, add 30 - 35 mg / L of NO3 - -N to the reactor, and control the dissolved oxygen in the reactor ≤ 0.5 mg / L, and perform anoxic starvation treatment on the sludge in the reactor for 2 - 5 days;

[0013] Add 10 - 15 mg / L of NH4 + -N, 40 - 45 mg / L of NO3 - -N and 180 - 220 mg / L of COD to the reactor after the anoxic starvation treatment, and the influent ratio is 35 - 40%; perform anoxic stirring, sedimentation, and drainage in sequence. When the nitrite accumulation rate in the SBR reactor ≥ 70%, the nitrite accumulation rate in the effluent ≥ 60%, and the nitrate nitrogen concentration ≤ 1 mg / L, the initiation of SBR short-cut denitrification is successful;

[0014] (B) Initiation of biofilm attachment of short-cut denitrification:

[0015] Put the blank polyurethane filler into the SBR reactor after the successful initiation of short-cut denitrification in step (A), and then add 10 - 15 mg / L of NH4 + -N, 40 - 45 mg / L of NO3 - -N, 180 - 220 mg / L of COD to the reactor, and the influent ratio is 35 - 40%; perform anoxic stirring, sedimentation, and drainage in sequence. When the sludge concentration on the polyurethane filler ≥ 3000 mg / L and the nitrite accumulation rate in the SBR reactor ≥ 70%, the initiation of biofilm attachment of short-cut denitrification is successful, and a polyurethane sponge biofilm is obtained;

[0016] (C) Start-up of continuous-flow short-cut denitrification biofilm module:

[0017] Put the polyurethane sponge biofilm in step (B) into the continuous-flow reactor, control the dissolved oxygen in the reactor ≤ 0.5 mg / L, and add 10 - 15 mg / L of NH4 + -N, 40 - 45 mg / L of NO3 - -N, 160 - 200 mg / L of COD, and the hydraulic retention time is 45 - 50 min;

[0018] When the NO3 - -N concentration in the effluent of the continuous-flow reactor < 10 mg / L, the effluent COD concentration < 60 mg / L, and the nitrite accumulation rate in the continuous-flow reactor ≥ 70%, start up the constructed continuous-flow short-cut denitrification biofilm module.

[0019] It should be noted that the influent ratio in this application refers to the ratio of the sewage volume entering the reactor to the effective volume of the reactor. For example, if the influent volume is 3 L and the effective volume of the reactor is 10 L, the influent ratio is 30%.

[0020] Furthermore, during the start-up process of SBR short-cut denitrification in step (A), the dissolved oxygen in the SBR reactor ≤ 0.5 mg / L;

[0021] Furthermore, during the start-up process of short-cut denitrification biofilm attachment in step (B), the dissolved oxygen in the SBR reactor ≤ 0.5 mg / L;

[0022] Furthermore, during the start-up process of the continuous-flow short-cut denitrification biofilm module in step (C), the dissolved oxygen in the continuous-flow reactor ≤ 0.5 mg / L.

[0023] Furthermore, during the start-up treatment of SBR short-cut denitrification in step (A), the time of anoxic stirring is 80 - 100 min, the time of sedimentation is 20 - 30 min, and the time of drainage is 3 - 5 min;

[0024] Furthermore, during the start-up treatment of biofilm attachment in step (B), the time of anoxic stirring is 80 - 100 min, the time of sedimentation is 20 - 30 min, and the time of drainage is 3 - 5 min.

[0025] Furthermore, the filling ratio of the blank polyurethane filler in step (B) is 25 - 30%.

[0026] Furthermore, the filling ratio of the polyurethane filler after successful attachment start-up in step (C) is 80 - 85%.

[0027] Further, the construction method further includes a step of running the continuous-flow short-cut denitrification biofilm module obtained by starting the construction in step (C) to a stable state, and the step includes:

[0028] Controlling the dissolved oxygen in the continuous-flow reactor after starting the continuous-flow short-cut denitrification biofilm module in step (C) to be ≤ 0.5 mg / L, adjusting the hydraulic retention time to 25 - 30 min, and adding 10 - 15 mg / L of NH4 + -N, 40 - 45 mg / L of NO3 - -N, 140 - 160 mg / L of COD;

[0029] When the concentration of NO3 - -N in the effluent < 10 mg / L, the concentration of COD in the effluent < 50 mg / L, and NTR ≥ 90%, and after maintaining for 15 - 20 d, it is considered that the continuous-flow short-cut denitrification biofilm module with a short hydraulic retention time has reached a stable state.

[0030] The continuous-flow short-cut denitrification biofilm module with a short hydraulic retention time obtained by the above construction method provided by the present invention.

[0031] The treatment device of the continuous-flow short-cut denitrification biofilm module with a short hydraulic retention time provided by the present invention, and the device includes: an SBR reaction system and a continuous-flow biofilm reaction system;

[0032] The SBR reaction system includes: a first nitrate inlet tank, a first organic matter inlet tank, and an SBR reactor, and the first nitrate inlet tank and the first organic matter inlet tank are respectively connected to the SBR reactor through pipelines;

[0033] The continuous-flow biofilm reaction system includes: a second nitrate inlet tank, a second organic matter inlet tank, and a continuous-flow reactor, and the second nitrate inlet tank and the second organic matter inlet tank are respectively connected to the continuous-flow reactor through pipelines;

[0034] The continuous-flow reactor is provided with a polyurethane sponge biofilm.

[0035] Further, the SBR reactor includes a first pH on-line measuring device, a first electric stirring device, and a first electric drain valve;

[0036] Further, the continuous-flow reactor includes a second pH on-line measuring device.

[0037] Furthermore, a first nitrate inlet water pump is arranged on the connecting pipeline between the first nitrate inlet tank and the SBR reactor;

[0038] And / or, a first organic matter inlet water pump is arranged on the connecting pipeline between the first organic matter inlet tank and the SBR reactor;

[0039] And / or, a second nitrate inlet water pump is provided on the connecting pipeline between the second nitrate inlet water tank and the continuous flow reactor;

[0040] And / or, a second organic matter inlet water pump is provided on the connecting pipeline between the second organic matter inlet water tank and the continuous flow reactor.

[0041] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0042] (1) The construction method of the present invention uses anoxic starvation treatment to quickly start short-cut denitrification, greatly shortening the start-up time and reducing resource consumption; the anoxic starvation treatment can effectively promote the reproduction of specific DNB bacteria, maintain the stable operation after the system is started, and has a certain impact load resistance ability.

[0043] (2) The present invention adopts a continuous flow short-cut denitrification module, which is simple and easy to control, can quickly achieve the accumulation of nitrite, and solves the problems of low nitrite accumulation rate, complex operation, and difficult regulation caused by the gradual decrease of nitrite concentration after reaching the peak value in one cycle in the SBR reactor and the gradual advance of the nitrite peak time with the shortening of the reaction cycle. It is an efficient and economical process with practical application value for providing nitrite for anaerobic ammonium oxidation.

[0044] (3) The short-cut denitrification biofilm module of the present invention has significant advantages such as short hydraulic retention time, large sewage treatment capacity, strong impact load resistance ability, and strong adaptability. Moreover, the biofilm method itself has the characteristics of high microbial population diversity and regional metabolism of functional microbial flora, which can improve the removal efficiency of organic matter and refractory pollutants, thereby improving the treatment efficiency. Brief Description of the Drawings

[0045] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0046] Figure 1 It is a schematic structural diagram of the SBR reaction system provided in Embodiment 1 of the present invention;

[0047] Figure 2 It is a schematic structural diagram of the continuous flow biofilm reaction system provided in Embodiment 1 of the present invention.

[0048] Icons: 1 - First nitrate inlet water tank; 2 - First organic matter inlet water tank; 3 - SBR reactor; 31 - First nitrate inlet water pump; 32 - First organic matter inlet water pump; 33 - First on-line pH measuring device; 34 - First electric stirring device; 35 - First electric drain valve; 4 - Second nitrate inlet water tank; 5 - Second organic matter inlet water tank; 6 - Continuous flow reactor; 61 - Second nitrate inlet water pump; 62 - Second organic matter inlet water pump; 63 - Polyurethane sponge biofilm; 64 - Second on-line pH measuring device. Detailed implementation mode

[0049] The technical solutions of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0050] According to one aspect of the present invention, a construction method for a continuous flow short-cut denitrification biofilm module with a short hydraulic retention time, the construction method comprising:

[0051] (A) Start-up of SBR short-cut denitrification:

[0052] Inoculate the remaining sludge from the sewage treatment plant into the anoxic SBR reactor 3 to make the sludge concentration in the reactor 2000 - 3000 mg / L, and then add 30 - 35 mg / L of NO3 - -N to the reactor, and control the dissolved oxygen in the reactor ≤ 0.5 mg / L, and conduct anoxic starvation treatment on the sludge in the reactor for 2 - 5 days;

[0053] Add 10 - 15 mg / L of NH4 + -N, 40 - 45 mg / L of NO3 - -N and 180 - 220 mg / L of COD to the reactor after the anoxic starvation treatment, and the influent ratio is 35 - 40%; conduct anoxic stirring, sedimentation, and drainage in sequence. When the nitrite accumulation rate in the SBR reactor 3 ≥ 70%, the nitrite accumulation rate in the effluent ≥ 60%, and the nitrate nitrogen concentration ≤ 1 mg / L, the start-up of SBR short-cut denitrification is successful;

[0054] (B) Start-up of the short-cut denitrification biofilm:

[0055] Put the blank polyurethane filler into the SBR reactor 3 after the successful start-up of the short-cut denitrification in step (A), and then add 10 - 15 mg / L of NH4 + -N, 40 - 45 mg / L of NO3 --N, COD of 180 - 220 mg / L, and an influent ratio of 35 - 40%; successively conduct anoxic agitation, sedimentation, and drainage. When the sludge concentration on the polyurethane packing ≥ 3000 mg / L and the nitrite accumulation rate in SBR reactor 3 ≥ 70%, the start-up of the shortcut denitrification biofilm attachment is successful, and the polyurethane sponge biofilm 63 is obtained.

[0056] (C) Start-up of the continuous-flow shortcut denitrification biofilm module:

[0057] Put the polyurethane sponge biofilm 63 from step (B) into the continuous-flow reactor 6, control the dissolved oxygen in the reactor ≤ 0.5 mg / L, and add 10 - 15 mg / L of NH4 + -N, 40 - 45 mg / L of NO3 - -N, COD of 160 - 200 mg / L, and a hydraulic retention time of 45 - 50 min;

[0058] When the NO3 - -N concentration in the effluent of the continuous-flow reactor 6 < 10 mg / L, the effluent COD concentration < 60 mg / L, and the nitrite accumulation rate in the continuous-flow reactor 6 ≥ 70%, start to construct and obtain the continuous-flow shortcut denitrification biofilm module.

[0059] The construction method of the continuous-flow shortcut denitrification biofilm module with a short hydraulic retention time provided by the present invention adopts an innovative construction strategy. In this application, the shortcut denitrification flocculent sludge is quickly started in the SBR reactor 3 by anoxic starvation treatment, then the biofilm attachment treatment is carried out, and finally the shortcut denitrification biofilm is put into the continuous-flow reactor 6 to realize the construction of the continuous-flow shortcut denitrification biofilm module with a short hydraulic retention time, greatly shortening the construction time and reaction time of the shortcut denitrification biofilm module, and solving the problems of low nitrite accumulation rate, complex operation, and difficult regulation caused by the fact that in the periodic operation of the SBR reactor 3, the nitrite concentration reaches the peak value in one cycle and then gradually decreases, and with the shortening of the reaction cycle, the appearance time of the nitrite peak gradually advances. At the same time, the continuous-flow shortcut denitrification biofilm module constructed in this application has high treatment efficiency, low energy consumption and operation cost, providing a new idea for supplying nitrite for the anaerobic ammonium oxidation process.

[0060] In a preferred embodiment of the present invention, during the start-up process of the SBR shortcut denitrification in step (A), the dissolved oxygen in the SBR reactor 3 ≤ 0.5 mg / L;

[0061] During the start-up process of the shortcut denitrification biofilm attachment in step (B), the dissolved oxygen in the SBR reactor 3 ≤ 0.5 mg / L;

[0062] As a preferred embodiment, during the start-up of SBR short-cut denitrification and the start-up of biofilm formation, the dissolved oxygen in the SBR reactor 3 needs to be controlled at ≤0.5 mg / L. Since denitrifying bacteria carry out denitrification reactions under anoxic conditions, it is necessary to control the dissolved oxygen concentration to ensure the normal anaerobic metabolism of denitrifying bacteria. If the dissolved oxygen is greater than 0.5 mg / L, the denitrifying bacteria will be inhibited, and the denitrifying bacteria will preferentially use oxygen as an electron acceptor for aerobic respiration, which is not conducive to the formation of short-cut denitrification.

[0063] In a preferred embodiment of the present invention, during the start-up process of the continuous-flow short-cut denitrification biofilm module in step (C), the dissolved oxygen in the continuous-flow reactor 6 is ≤0.5 mg / L.

[0064] As a preferred embodiment, during the start-up process of the above-mentioned continuous-flow short-cut denitrification biofilm module, the dissolved oxygen in the continuous-flow reactor 6 is ≤0.5 mg / L, and the principle is the same as that of the start-up of SBR short-cut denitrification and the start-up of biofilm formation. If the dissolved oxygen is greater than 0.5 mg / L, the denitrifying bacteria will be inhibited, and the denitrifying bacteria will preferentially use oxygen as an electron acceptor for aerobic respiration, which is not conducive to the formation of short-cut denitrification.

[0065] In a preferred embodiment of the present invention, in the SBR short-cut denitrification start-up treatment in step (A), the anoxic stirring time is 80 - 100 min, the sedimentation time is 20 - 30 min, and the drainage time is 3 - 5 min; in the biofilm formation start-up treatment in step (B), the anoxic stirring time is 80 - 100 min, the sedimentation time is 20 - 30 min, and the drainage time is 3 - 5 min.

[0066] In a preferred embodiment of the present invention, the filling ratio of the blank polyurethane filler in step (B) is 25 - 30%.

[0067] As a preferred embodiment, the filling ratio (25% - 30%) of the above-mentioned blank polyurethane filler in the present application can provide sufficient attachment surfaces for microorganisms, promote the formation and stability of biofilms, maintain a high biomass, and thus improve the sewage treatment efficiency. If there is too much polyurethane filler (greater than 30%), it will increase the resistance inside the SBR reactor 3 and affect the effluent quality of the system; too much polyurethane filler may also cause the activated sludge to not fully and evenly attach to the filler, thus affecting the formation of biofilms. And too little biofilm will lead to insufficient subsequent biomass and it is difficult to cope with water quality with high concentrations or large fluctuations in pollutant concentrations.

[0068] In a preferred embodiment of the present invention, the filling ratio of the polyurethane filler after successful biofilm formation start-up in step (C) is 80 - 85%.

[0069] As a preferred embodiment, the filling ratio of the polyurethane filler after successful film hanging and startup is 80-85%. This filling ratio can not only maintain a high biomass in the reactor but also enable the reactor to operate normally. If the ratio is higher than this value, the polyurethane filler may increase the resistance inside the reactor, causing reactor blockage, and thus affecting the microbial community structure inside the continuous flow reactor 6. While a lower ratio of polyurethane filler may lead to insufficient biomass in the continuous flow reactor 6, making it difficult to handle water quality with high concentrations or large fluctuations in pollutant concentrations.

[0070] In a preferred embodiment of the present invention, the construction method further includes a step of operating the continuous flow shortcut denitrification biofilm module obtained by starting the construction in step (C) to a stable state, and the steps include:

[0071] Control the dissolved oxygen in the continuous flow reactor 6 after starting the continuous flow shortcut denitrification biofilm module in step (C) to ≤0.5 mg / L, adjust the hydraulic retention time to 25-30 min, and add 10-15 mg / L of NH4 + -N, 40-45 mg / L of NO3 - -N, 140-160 mg / L of COD;

[0072] When the concentration of NO3 - -N in the effluent < 10 mg / L, the concentration of COD in the effluent < 50 mg / L, and NTR ≥ 90%, and after maintaining for 15-20 d, it is considered that the continuous flow shortcut denitrification biofilm module with a short hydraulic retention time has reached a stable state.

[0073] According to one aspect of the present invention, the continuous flow shortcut denitrification biofilm module with a short hydraulic retention time obtained by the above construction method.

[0074] The continuous flow shortcut denitrification biofilm module provided by the present invention is constructed by the above construction method. This continuous flow shortcut denitrification biofilm module not only has the advantage of high treatment efficiency but also has low energy consumption and operating costs.

[0075] According to one aspect of the present invention, a treatment device for the continuous flow shortcut denitrification biofilm module with a short hydraulic retention time, the device includes: an SBR reaction system and a continuous flow biofilm reaction system;

[0076] The SBR reaction system includes: a first nitrate inlet water tank 1, a first organic matter inlet water tank 2, and an SBR reactor 3. The first nitrate inlet water tank 1 and the first organic matter inlet water tank 2 are respectively connected to the SBR reactor 3 through pipelines;

[0077] The continuous flow biofilm reaction system includes: a second nitrate inlet water tank 4, a second organic matter inlet water tank 5, and a continuous flow reactor 6. The second nitrate inlet water tank 4 and the second organic matter inlet water tank 5 are respectively connected to the continuous flow reactor 6 through pipelines;

[0078] The continuous flow reactor 6 is provided with a polyurethane sponge biofilm 63.

[0079] In a preferred embodiment of the present invention, the SBR reactor 3 includes a first pH on-line measuring device 33, a first electric stirring device 34 and a first electric drain valve 35;

[0080] In a preferred embodiment of the present invention, the continuous flow reactor 6 includes a second pH on-line measuring device 64.

[0081] In the above preferred embodiment, a first nitrate inlet water pump 31 is arranged on the connecting pipeline between the first nitrate inlet water tank 1 and the SBR reactor 3;

[0082] A first organic matter inlet water pump 32 is arranged on the connecting pipeline between the first organic matter inlet water tank 2 and the SBR reactor 3;

[0083] A second nitrate inlet water pump 61 is arranged on the connecting pipeline between the second nitrate inlet water tank 4 and the continuous flow reactor 6;

[0084] A second organic matter inlet water pump 62 is arranged on the connecting pipeline between the second organic matter inlet water tank 5 and the continuous flow reactor 6.

[0085] Hereinafter, the technical solution of the present invention will be further described in conjunction with embodiments.

[0086] Embodiment 1

[0087] The construction of a continuous flow short-cut denitrification biofilm module with a short hydraulic retention time and a sewage treatment device, the device includes: an SBR reaction system and a continuous flow biofilm reaction system;

[0088] Figure 1 It is a structural schematic diagram of the SBR reaction system provided for this embodiment.

[0089] See Figure 1 , the SBR reaction system includes: a first nitrate inlet water tank 1, a first organic matter inlet water tank 2, an SBR reactor 3. The first nitrate inlet water tank 1 and the first organic matter inlet water tank 2 are respectively connected to the SBR reactor 3 through pipelines;

[0090] In a preferred embodiment of this embodiment, the SBR reactor 3 includes a first pH on-line measuring device 33 for monitoring the pH value in the SBR reactor 3.

[0091] In a preferred embodiment of the present embodiment, the SBR reactor 3 includes a first electric stirring device 34 for stirring the materials in the SBR reactor 3.

[0092] In a preferred embodiment of the present embodiment, the SBR reactor 3 includes a first electric drain valve 35 for draining water.

[0093] Continue to refer to Figure 1 , a first nitrate inlet water pump 31 is provided on the communication pipeline between the first nitrate inlet water tank 1 and the SBR reactor 3; a first organic matter inlet water pump 32 is provided on the communication pipeline between the first organic matter inlet water tank 2 and the SBR reactor 3;

[0094] As a preferred embodiment, the first nitrate inlet water pump 31 and the first organic matter inlet water pump 32 are used to control the C / N ratio in the SBR reactor 3 during the start-up of SBR short-cut denitrification and the start-up of biofilm formation.

[0095] Figure 2 It is a schematic structural diagram of the continuous flow biofilm reaction system provided for this embodiment.

[0096] Refer to Figure 2 , the continuous flow biofilm reaction system includes: a second nitrate inlet water tank 4, a second organic matter inlet water tank 5, and a continuous flow reactor 6. The second nitrate inlet water tank 4 and the second organic matter inlet water tank 5 are respectively connected to the continuous flow reactor 6 through pipelines;

[0097] The continuous flow reactor 6 has a polyurethane sponge biofilm 63.

[0098] Embodiment 2

[0099] A construction method of a continuous flow short-cut denitrification biofilm module with a short hydraulic retention time, the method includes:

[0100] (1), the start-up stage of SBR system short-cut denitrification activated sludge:

[0101] The remaining sludge of the sewage treatment plant is inoculated into the SBR reactor 3 with an effective volume of 5L, and the sludge concentration is 2566mg / L. 30mg / L of NO3 - -N is added to the reactor. Except for NO3 - -N, no other nutrients are added to the reactor. The dissolved oxygen in the reactor is controlled to be lower than 0.5mg / L, and the inoculated sludge is subjected to anoxic starvation treatment for 2 days; on the third day, 10mg / L of NH4 + -N and 40mg / L of NO3 --N, COD of 200 mg / L, influent ratio of 40%, with anoxic stirring for 90 min, sedimentation for 30 min, and then drainage for 3 min through an electric drain valve;

[0102] When the maximum nitrite accumulation rate in the SBR reactor 3 reaches 76.5% and the effluent nitrite accumulation rate reaches 72.4%, and the nitrate nitrogen concentration is almost 0, it is considered that the short-cut denitrification in the SBR system is successfully started;

[0103] (2) Start-up stage of biofilm formation for short-cut denitrification in the SBR system:

[0104] Put blank polyurethane fillers into the SBR reactor 3 with a filling ratio of 25%, add 10 mg / L of NH4 + -N, 40 mg / L of NO3 - -N, COD of 200 mg / L, influent ratio of 40%, with anoxic stirring for 80 - 100 min, sedimentation for 30 min, and then drainage for 3 min through an electric drain valve;

[0105] When the concentration of flocculent sludge in the SBR reactor 3 decreases significantly, the surface of the filler changes from light yellow to dark yellow, the sludge concentration on the filler increases significantly, reaching more than 4100 mg / L, and the NTR of biofilm short-cut denitrification reaches more than 75.9%, it is considered that the start-up of biofilm formation for short-cut denitrification in the SBR system is successful;

[0106] (3) Start-up stage of continuous-flow short-cut denitrification biofilm module with short hydraulic retention time:

[0107] Put the short-cut denitrification biofilm of the SBR reactor 3 into the continuous-flow reactor 6 with a biofilm filling ratio of 82%, control the dissolved oxygen in the reactor to be less than 0.5 mg / L, the hydraulic retention time to be 50 min, and add 10 mg / L of NH4 + -N, 40 mg / L of NO3 - -N, COD of 200 mg / L;

[0108] When the effluent NO3 - -N concentration is stable below 10 mg / L, the effluent COD concentration is less than 60 mg / L, and the NTR reaches 80%, it is considered that the construction of the continuous-flow short-cut denitrification biofilm module with short hydraulic retention time is successful.

[0109] (4) Stable operation stage of continuous-flow short-cut denitrification biofilm module with short hydraulic retention time:

[0110] Control the dissolved oxygen in the reactor to be less than 0.5 mg / L, adjust the hydraulic retention time to 30 min, and add 10 mg / L of NH4 +-N, NO3 at 40 mg / L - -N, COD at 150 mg / L;

[0111] When the effluent NO3 - -N concentration is less than 10 mg / L, the effluent COD concentration is less than 50 mg / L, the NTR reaches 92%, and after maintaining for 15 - 20 d (days), it is considered that the continuous-flow shortcut denitrification biofilm module with short hydraulic retention time reaches a stable state.

[0112] Furthermore, using the continuous-flow shortcut denitrification biofilm module with short hydraulic retention time constructed in this embodiment for sewage treatment, the specific method is as follows:

[0113] Keep the hydraulic retention time in the reactor at 30 min, add 10 mg / L of NH4 + -N, NO3 at 40 mg / L - -N, COD at 150 mg / L and operate normally; the removal efficiency of effluent NH4 + -N reaches 80%, the accumulated concentration of effluent NO2 - -N reaches more than 30 mg / L, and the removal efficiency of NO3 - -N is further improved, exceeding the level of 80%, and at the same time the NTR is stably at a high level above 90%, showing the efficient operation of the PD process.

[0114] Comparative Example 1

[0115] A method for constructing a continuous-flow shortcut denitrification biofilm module with short hydraulic retention time, the method includes:

[0116] (1), Inoculate the excess sludge from the sewage treatment plant into the SBR reactor 3 with an effective volume of 5 L, the sludge concentration is 2566 mg / L, add 10 mg / L of NH4 + -N, NO3 at 40 mg / L - -N, COD at 200 mg / L, the influent ratio is 40%, and stir anoxically for 90 min, precipitate for 30 min, and then drain water through the electric drain valve for 3 min;

[0117] (2), Put the blank polyurethane filler into the SBR reactor 3, the filling ratio is 25%, add 10 mg / L of NH4 + -N, NO3 at 40 mg / L - -N, COD at 200 mg / L, the influent ratio is 40%, and stir anoxically for 80 - 100 min, precipitate for 30 min, and then drain water through the electric drain valve for 3 min;

[0118] (3) Put the short-cut denitrifying biofilm of the SBR reactor 3 into the continuous flow reactor 6, with a biofilm filling ratio of 82%, control the dissolved oxygen in the reactor to be less than 0.5 mg / L, the hydraulic retention time is 50 min, and add 10 mg / L of NH4 + -N and 40 mg / L of NO3 - -N, and 200 mg / L of COD;

[0119] (4) Control the dissolved oxygen in the reactor to be less than 0.5 mg / L, adjust the hydraulic retention time to 30 min, and add 10 mg / L of NH4 + -N and 40 mg / L of NO3 - -N, and 150 mg / L of COD.

[0120] The technical solution of this example is the same as that of Example 2 except that the starvation treatment in step (1) is not carried out.

[0121] The activity of the short-cut denitrifying bacteria group in the continuous flow short-cut denitrification module without starvation treatment is insufficient, and the short-cut denitrification cannot be started quickly, resulting in too high NO3 - -N concentration in the effluent of the obtained module and a lower NTR (less than 40%).

[0122] Comparative Example 2

[0123] A construction method of a continuous flow short-cut denitrifying biofilm module with a short hydraulic retention time, the method comprising:

[0124] (1) Start-up stage of the short-cut denitrifying activated sludge in the SBR system: the same as Example 2.

[0125] (2) Biofilm attachment start-up stage of the short-cut denitrifying biofilm in the SBR system: the same as Example 2.

[0126] (3) Start-up stage of the continuous flow short-cut denitrifying biofilm module with a short hydraulic retention time: the same as Example 2.

[0127] (4) Stable operation stage of the continuous flow short-cut denitrifying biofilm module with a short hydraulic retention time:

[0128] Control the dissolved oxygen in the reactor to be less than 0.5 mg / L, adjust the hydraulic retention time to 50 min, and add 10 mg / L of NH4 + -N and 40 mg / L of NO3 - -N, and 200 mg / L of COD;

[0129] The difference between this comparative example and Example 2 is that in step (4), the hydraulic retention time is 50 min and the addition amount of COD is 200 mg / L.

[0130] Under these conditions, the effluent COD concentration of the comparative example system is relatively high, the removal rate is not high, and the accumulated concentration of NO2 - -N shows a decreasing trend, and the NTR is only stable at 60%. It can be seen that when the continuous-flow short-cut denitrification biofilm module of the present application operates stably, the hydraulic retention time and COD concentration have a significant impact on the stable operation of the module.

[0131] In summary, compared with the existing methods of starting short-cut denitrification in the SBR reactor 3 by reducing the carbon-nitrogen ratio and increasing the pH, etc., the time period required for the existing methods to start short-cut denitrification is relatively long, and the shortest is also one month. Moreover, the adjustment process of the carbon-nitrogen ratio and pH is relatively complex and requires precise control. However, the starvation treatment method adopted by the present invention can be successfully started within an ultra-short time (2-3 days), with a short start-up period and simple operation.

[0132] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for constructing a continuous flow short-range denitrification biofilm module with a short hydraulic retention time, characterized in that: The construction method comprises: (A) Start-up of SBR short-range denitrification: The anoxic SBR reactor is inoculated with residual sludge from the secondary sedimentation tank of the sewage treatment plant or activated sludge from the biochemical pool to make the sludge concentration in the reactor 2000-3000 mg / L, and then 30-35 mg / L of NO3 is added to the reactor. - -N, and control the dissolved oxygen in the reactor ≤ 0.5 mg / L, and subject the sludge in the reactor to anoxic starvation treatment for 2 to 5 days; Add 10-15 mg / L NH4 to the reactor after anoxic starvation treatment. + -N, 40-45 mg / L NO3 - -N and 180-220mg / L COD, the water inlet ratio is 35-40%; anoxic stirring, sedimentation, and drainage are carried out in sequence. When the nitrite accumulation rate in the SBR reactor is ≥70%, the nitrite accumulation rate in the effluent is ≥60%, and the nitrate nitrogen concentration is ≤1mg / L, the SBR short-range denitrification is successfully started; (B) Start-up of short-range denitrification biofilm: Put the blank polyurethane filler into the SBR reactor after the short-range denitrification is successfully started in step (A), and then add 10-15 mg / L NH4 + -N, 40-45 mg / L NO3 - -N, 180-220mg / L COD, 35-40% water inlet ratio; anoxic stirring, sedimentation, and drainage are performed in sequence. When the sludge concentration on the polyurethane filler is ≥3000mg / L, and the nitrite accumulation rate in the SBR reactor is ≥70%, the short-range denitrification biofilm is successfully started to obtain a polyurethane sponge biofilm; (C) Start-up of continuous flow short-range denitrification biofilm module: The polyurethane sponge biofilm in step (B) is placed in a continuous flow reactor, the dissolved oxygen in the reactor is controlled to be ≤0.5 mg / L, and 10-15 mg / L of NH4 is added to the reactor. + -N, 40-45 mg / L NO3 - -N, COD of 160-200 mg / L, hydraulic retention time of 45-50 min; When the effluent NO3 - When the -N concentration is less than 10 mg / L, the effluent COD concentration is less than 60 mg / L, and the nitrite accumulation rate in the continuous flow reactor is ≥70%, the construction is started to obtain a continuous flow short-range denitrification biofilm module.

2. The construction method according to claim 1, characterized in that: During the SBR short-cut denitrification startup process in step (A), the dissolved oxygen in the SBR reactor is ≤0.5 mg / L; And / or, during the startup process of the short-range denitrification biofilm formation in step (B), the dissolved oxygen in the dissolved oxygen reactor in the SBR reactor is ≤0.5 mg / L; And / or, during the startup of the continuous flow short-range denitrification biofilm module in step (C), the dissolved oxygen in the continuous flow reactor is ≤0.5 mg / L.

3. The construction method according to claim 1, characterized in that: In the step (A) of SBR short-range denitrification start-up treatment, the anoxic stirring time is 80 to 100 minutes, the sedimentation time is 20 to 30 minutes, and the drainage time is 3 to 5 minutes; And / or, in the biofilm formation start-up treatment of step (B), the anoxic stirring time is 80 to 100 minutes, the sedimentation time is 20 to 30 minutes, and the drainage time is 3 to 5 minutes.

4. The construction method according to claim 1, characterized in that: The filling ratio of the blank polyurethane filler in step (B) is 25-30%.

5. The construction method according to claim 1, characterized in that: After the film formation in step (C) is successfully started, the filling ratio of the polyurethane filler is 80-85%.

6. The construction method according to claim 1, characterized in that: The construction method further comprises the step of operating the continuous flow short-range denitrification biofilm module obtained by starting the construction in step (C) to a stable state, the step comprising: Control step (C) After the continuous flow short-range denitrification biofilm module is started, the dissolved oxygen in the continuous flow reactor is ≤0.5 mg / L, the hydraulic retention time is adjusted to 25-30 min, and 10-15 mg / L of NH4 is added to the reactor. + -N, 40-45 mg / L NO3 - -N, COD of 140-160 mg / L; When the water NO3 - When the -N concentration is less than 10 mg / L, the effluent COD concentration is less than 50 mg / L, and the NTR is ≥ 90%, and maintained for 15 to 20 days, it is considered that the continuous flow short-range denitrification biofilm module with a short hydraulic retention time has reached a stable state.

7. A continuous flow short-range denitrification biofilm module with a short hydraulic retention time obtained by the construction method according to any one of claims 1 to 6.

8. A construction and treatment device for a continuous flow short-range denitrification biofilm module with a short hydraulic retention time according to claim 7, characterized in that: The device comprises: an SBR reaction system and a continuous flow biofilm reaction system; The SBR reaction system comprises: a first nitrate water inlet tank, a first organic matter water inlet tank, and an SBR reactor, wherein the first nitrate water inlet tank and the first organic matter water inlet tank are respectively connected to a pipeline of the SBR reactor; The continuous flow biofilm reaction system comprises: a second nitrate water inlet tank, a second organic matter water inlet tank, and a continuous flow reactor, wherein the second nitrate water inlet tank and the second organic matter water inlet tank are respectively connected to a continuous flow reactor pipeline; The continuous flow reactor is provided with a polyurethane sponge biofilm.

9. The construction processing device according to claim 8, characterized in that: The SBR reactor comprises a first pH online measuring device, a first electric stirring device and a first electric drain valve; And / or, the continuous flow reactor comprises a second pH online measuring device.

10. The construction processing device according to claim 8, characterized in that: A first nitrate water inlet pump is provided on the connecting pipe between the first nitrate water inlet tank and the SBR reactor; And / or, a first organic matter water inlet pump is provided on the connecting pipe between the first organic matter water inlet tank and the SBR reactor; And / or, a second nitrate water inlet pump is provided on the connecting pipe between the second nitrate water inlet tank and the continuous flow reactor; And / or, a second organic water inlet pump is provided on the connecting pipe between the second organic water inlet tank and the continuous flow reactor.

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