Deep nitrogen removal process by coupling partial denitrification with anaerobic ammonia oxidation

Abstract

The invention relates to a partial denitrification coupled anaerobic ammonia oxidation deep denitrification process, which comprises the following steps: adding gel particles which have a nitrogen adsorption function, have biocompatibility and can be fluidized in a reactor to promote enrichment interception and synergistic symbiosis of AnAOB and DNB, and creating a local microenvironment with higher substrate concentration for the AnAOB and the DNB through the nitrogen adsorption effect, so as to realize deep denitrification of the AnAOB and the DNB. According to the present invention, the disadvantages of low concentration, hunger stress caused by torsion and unbalanced competition of AnAOB and DNB are overcome, and through process parameter optimization and process regulation and control, the interception enrichment, the activity improvement and the synergistic symbiosis of the PD / A key functional bacteria are finally achieved, and the low-carbon high-load PD / A deep nitrogen removal is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of environmental protection, and particularly relates to a partial denitrification coupled anaerobic ammonia oxidation deep denitrification process. Background Art

[0002] In order to meet the sewage discharge standards, sewage treatment plants generally use the denitrification deep denitrification process, which is an effective way to reduce the TN concentration of the secondary effluent of urban sewage treatment plants. However, this process requires the addition of a large amount of organic carbon source to meet the denitrification standards, and will also increase the sludge production, and finally lead to an increase of 10% to 20% in sewage treatment costs and operating costs; in addition, the denitrification process is prone to produce N2O with a strong greenhouse effect. Therefore, low-carbon deep denitrification technology is in urgent need of development.

[0003] The anaerobic ammonia oxidation process (Anammox, Anaerobic Ammonia Oxidation) discovered by Dutch scholars in the 1990s can convert NH4 + -N and NO 2- -N is converted into N2 for removal. Compared with traditional nitrification and denitrification, Anammox does not require aeration energy consumption, does not require carbon source addition, and can reduce N2O emissions and sludge production. + -N, but NO 2- -N often needs to be obtained through coupling with other nitrogen transformation pathways. According to the principle of microbial nitrogen transformation, partial denitrification-anaerobic ammonia oxidation (PD / A) is expected to become an alternative solution for low-carbon denitrification of municipal sewage, that is, partial denitrification bacteria (PDB) convert NO 3- -N is converted to NO 2- -N, then, Anammox bacteria (AnAOB, Anaerobic Ammonia Oxidation Bacteria) use the NO2 generated by the PD process - -N and NH4 in sewage + -N reacts to generate N2; however, the current application of PD / A in deep denitrification still has the following technical difficulties:

[0004] The first is the enrichment and retention of the core functional bacteria AnAOB in the PD / A process. AnAOB is an autotrophic bacterium with a long generation cycle. The low abundance of AnAOB in sludge is one of the problems that limit the success of the Anammox coupling process; therefore, how to enrich and retain AnAOB is one of the key issues in the implementation of the PD / A process.

[0005] The second is the synergistic metabolism and balance of the two types of functional bacteria in the PD / A coupling process under low concentration conditions. The growth rate of AnAOB is much lower than that of DNB. Low nitrogen concentration will lead to a decrease in the microbial reaction rate, making it difficult to maintain the balance between DNB and AnAOB, and reducing the denitrification volumetric efficiency. How to balance DNB and AnAOB to improve the reactor volumetric efficiency is also a huge challenge facing the PD / A deep denitrification process.

[0006] Third, in the biological denitrification process, microorganisms secrete extracellular polymers (EPS) to form aggregates such as biofilms or granular sludge to ensure the retention of denitrification functional bacteria and stable denitrification; however, in the deep denitrification system facing low substrate concentration, microorganisms are susceptible to starvation stress. Not only is it difficult to synthesize new EPS, but existing EPS may also be consumed as energy, causing the aggregates to disintegrate or fall off, which in turn leads to the worsening of the retention of AnAOB. ​​Therefore, how to reduce the starvation stress caused by low nitrogen concentration is another challenge to ensure the efficient and stable operation of the PD / A deep denitrification system.

[0007] In view of the above technical difficulties, it is difficult for the existing PD / A process to achieve low concentrations of TN and NH4 + Deep denitrification under -N inlet conditions cannot stably and long-term meet the more stringent (A or first-level) urban sewage treatment plant effluent discharge requirements in developed areas, that is, TN <10mg / L and NH4+-N <1~5mg / L. Summary of the invention

[0008] In order to overcome the shortcomings of the above-mentioned prior art, the purpose of the present invention is to provide a partial denitrification coupled anaerobic ammonia oxidation deep denitrification process, which promotes the enrichment, retention and synergistic symbiosis of AnAOB and DNB by adding gel particles with nitrogen adsorption function, biological affinity and fluidization in the reactor. At the same time, a local higher substrate concentration microenvironment is created for them through nitrogen adsorption, reversing the starvation stress caused by low concentration and the disadvantage of unbalanced competition between AnAOB and DNB. Through process parameter optimization and process regulation, the retention, enrichment, activity enhancement and synergistic symbiosis of PD / A key functional bacteria are finally achieved, realizing low-carbon and high-load PD / A deep denitrification.

[0009] To achieve the above object, the present invention adopts the following technical solutions:

[0010] A partial denitrification coupled anaerobic ammonium oxidation deep denitrification process comprises the following steps:

[0011] S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is (2-3): (3-5), the filling rate is 20%-30%; filling PVA / PA / ZL gel carrier, the filling rate is 20-30%;

[0012] S2, NH4 + -N, NO 3- -N was used as substrate to start and operate the reactor, NaAc was used as carbon source, and the influent COD / TN was controlled at 2.5-4.0; NH4 + -N: 7.5-20mg·L -1 NH4Cl, NO3 - -N: 7.5-20mg·L -1 of NaNO3;

[0013] S3, collect inlet and outlet water samples more than 3 times a week, and use the national standard method to determine NH4 + -N, NO 2- -N, NO 3- -N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor;

[0014] S4, after the operation of the reactor is stable, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the extracellular polysaccharide PS (Polysaccharide) and extracellular protein content PN (Protein), the sum of PN and PS is the concentration of extracellular polymer EPS (extracellular polymeric substances); use Illumina Miseq sequencing platform to test 16s rRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia;

[0015] S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4 ) was used to reflect the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB.

[0016] The deep denitrification effect of the step S3 reactor is:

[0017] Average effluent NH4 + -N concentration is 1.7~3.4mg·L -1 ;

[0018] Average outlet NO2 --N concentration is 0.1~1.3mg·L -1 ;

[0019] Average outlet NO3 - -N concentration is 3.4~6.4mg·L -1 ;

[0020] The TN concentration of the effluent is 6.0~9.5mg·L -1 ;

[0021] Total nitrogen removal rate is 50.7-76.3%;

[0022] The average effluent meets the A (first level) standard of urban sewage treatment plant effluent quality standards in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L.

[0023] In step S4, the extracellular polysaccharide PS (Polysaccharide) and extracellular protein content PN (Protein), PN and PS add up to the extracellular polymer EPS (extracellular polymeric substances) concentration is:

[0024] PN concentration: 28.60~34.26mg·g-VSS -1 ;

[0025] PS concentration: 8.33~18.01mg·g-VSS -1 ;

[0026] EPS concentration: 36.71~48.65mg·g-VSS -1 ;

[0027] The enrichment effects of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effects of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia are as follows:

[0028] Thauera abundance: 2.17-2.25%;

[0029] The abundance of Pseudomonas is: 1.01-4.59%;

[0030] Candidatus_Brocadia abundance: 2.36-3.19%;

[0031] Candidatus_Kuenenia abundance: 0.54%~1.44%;

[0032] Microorganisms buffer the impact of hydraulic scouring on biofilm by secreting EPS. Typical denitrifying bacteria Thauera and Pseudomonas, as well as anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia all maintain a certain abundance ratio, indicating that the carrier is conducive to the synergistic symbiosis of functional microorganisms.

[0033] The nitrate reduction rate (r) of step S5 NO3 ), nitrite generation rate (r NO2 ), ammonia nitrogen consumption rate (r NH4 )for:

[0034] Nitrate reduction rate (r NO3 ) is 809.40~1506.58mg-N·g-VSS -1 ·d -1 ;

[0035] Nitrite generation rate (r NO2 ) is 761.07~1170.41mg-N·g-VSS -1 ·d -1 ;

[0036] Ammonia nitrogen consumption rate (r NH4 ) is 333.37~538.43mg-N·g-VSS -1 ·d -1 ;

[0037] It can be seen that DNB and AnAOB in the carrier biofilm can respond to environmental shocks synchronously and have good buffering capacity, which has a positive significance for the stable operation of the low-concentration PD / A process, that is, sufficient partial denitrification activity can continuously provide sufficient NO for the Anammox process. 2- -N, thereby enhancing the system's denitrification capacity and maintaining the continuous and stable denitrification of PD / A.

[0038] The PVA / PA / ZL gel carrier in step S1 is a biological carrier with ammonia nitrogen adsorption and desorption function, which is a polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA / ZL loaded with zeolite, with a zeolite loading of 2-6%, a microbead diameter of 3.0-5.0 mm, and a specific surface area of ​​13.8-19.0 m 2 ·g -1 , the sedimentation rate is 247.0~274.2m·h -1 ; The equilibrium adsorption capacity Q for ammonia nitrogen calculated by pseudo-second-order kinetics simulation e 0.64~0.94mg·g -1The maximum adsorption capacity Q of ammonia nitrogen calculated by Langmuir model m 1.03~2.76mg·g -1 .

[0039] The reactor in step S2 adopts a UASB reactor system. The reactor is cylindrical with a height-to-diameter ratio of 10 to 15. The water flow path is bottom-in and top-out. An insulation jacket is provided on the outer layer of the reactor. The reactor temperature is controlled at 25 to 35° C. by water bath circulation. The reactor is shading treated to reduce the impact of light on microorganisms.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] (1) The present invention synthesizes a bio-carrier with ammonia nitrogen adsorption and desorption functions, so that it has both the ability to adsorb and desorb ammonia nitrogen and the biological affinity to quickly form a biofilm. The bio-carrier directional adsorbs ammonia nitrogen, creates a competitive advantage for the attached and growing AnAOB, and is beneficial to the enrichment and retention of AnAOB, thus breaking through the limitation that the slow growth of AnAOB and the loss of hydraulic scouring result in insufficient biomass and thus makes it difficult to achieve low-carbon denitrification.

[0042] (2) The present invention creates a good microhabitat for the symbiosis of AnAOB and PDB by using biological carriers with ammonia nitrogen adsorption and desorption functions. In the deep denitrification system facing low substrate concentration, the biological carriers with ammonia nitrogen adsorption and desorption functions can quickly adsorb ammonia nitrogen and create a higher substrate concentration domain in the gaps of the biological carriers, thereby alleviating the impact of low substrate concentration on PDB and AnAOB, thereby avoiding the problem of biofilm disintegration and shedding caused by starvation stress, which is beneficial to the maintenance of the denitrification balance of DNB and AnAOB coupling, and provides a technical basis for the low-cost deep denitrification process suitable for low substrate concentration and low C / N urban sewage.

[0043] (3) The gel particle biocarrier synthesized in the present invention has good sedimentation performance and can be fluidized in an upflow UASB reactor, thereby avoiding the blockage obstacles existing in fixed bed reactors and the additional energy consumption caused by regular backwashing. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 Schematic diagram of the process of an embodiment of the present invention.

[0045] Figure 2 Schematic diagram of the UASB reactor system of the embodiment of the present invention and the comparative example. DETAILED DESCRIPTION

[0046] The present invention is described in detail below in conjunction with embodiments and drawings.

[0047] Example 1, reference Figure 1, a partial denitrification coupled anaerobic ammonium oxidation deep denitrification process, comprising the following steps:

[0048] S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is 2:3, and the filling rate is 20%; filled with PVA / PA / ZL gel carrier, the filling rate is 20%;

[0049] S2, NH4 + -N(NH4Cl, 20mg·L -1 )、NO3 - -N(NaNO3, 20mg·L -1 ) as substrate to start and operate the reactor, using NaAc as carbon source, and controlling the influent COD / TN to 2.5;

[0050] S3, collect inlet and outlet water samples three times a week, and use the national standard method to determine NH4 + -N, NO 2- -N, NO 3- -N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor;

[0051] Average effluent NH4 + -N concentration is 3.4 mg·L -1 ;

[0052] Average outlet NO2 - -N concentration is 0.2 mg·L -1 ;

[0053] Average outlet NO3 - -N concentration is 6.4 mg·L -1 ;

[0054] The TN concentration of the effluent is 9.5 mg·L -1 ;

[0055] The total nitrogen removal rate was 76.3%;

[0056] The average effluent meets the A (first level) standard of urban sewage treatment plant effluent quality standards in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L;

[0057] S4, after the reactor runs stably, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the extracellular polysaccharide (PS) and extracellular protein content (PN), and the sum of PN and PS is the extracellular polymeric substances (EPS) concentration; use Illumina Miseq sequencing platform to test 16s rRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia;

[0058] PN concentration: 30.64 mg g-VSS -1 ;

[0059] PS concentration: 18.01 mg g-VSS -1 ;

[0060] EPS concentration: 48.65mg·g-VSS -1 ;

[0061] Thauera abundance: 2.23%;

[0062] The abundance of Pseudomonas is: 2.58%;

[0063] Candidatus_Brocadia abundance: 2.36%;

[0064] Candidatus_Kuenenia abundance: 1.44%;

[0065] Microorganisms buffer the impact of hydraulic scouring on biofilm by secreting EPS. Typical denitrifying bacteria Thauera and Pseudomonas, as well as anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia all maintain a certain abundance ratio, indicating that the carrier is conducive to the symbiosis of functional microorganisms.

[0066] S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4) reflects the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB;

[0067] Nitrate reduction rate (r NO3 ) is 1085.54 mg-N g-VSS -1 ·d -1 ;

[0068] Nitrite generation rate (r NO2 ) is 891.71 mg-N g-VSS -1 ·d -1 ;

[0069] Ammonia nitrogen consumption rate (r NH4 ) is 455.58 mg-N g-VSS -1 ·d -1 ;

[0070] It can be seen that DNB and AnAOB in the carrier biofilm can respond to environmental shocks synchronously and have good buffering capacity, which has a positive significance for the stable operation of the low-concentration PD / A process, that is, sufficient partial denitrification activity can continuously provide sufficient NO for the Anammox process. 2- -N, thereby enhancing the system's denitrification capacity and maintaining the continuous and stable denitrification of PD / A.

[0071] The PVA / PA / ZL gel carrier in step S1 is a biological carrier with ammonia nitrogen adsorption and desorption function, which is a polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA / ZL loaded with zeolite, with a zeolite loading of 2%, a microbead diameter of 3.0 mm, and a specific surface area of ​​18.8 m 2 ·g -1 , the sedimentation rate is 247.0m·h -1 ; The equilibrium adsorption capacity Q for ammonia nitrogen calculated by pseudo-second-order kinetics simulation e 0.64 mg·g -1 The maximum adsorption capacity Q of ammonia nitrogen calculated by Langmuir model m 1.03 mg·g -1 .

[0072] The reactor in step S2 adopts a UASB reactor system, as shown in the attached Figure 2 As shown, the reactor is cylindrical with a height-to-diameter ratio of 10, the water flow path is bottom-in and top-out, an insulation jacket is provided on the outer layer of the reactor, and the reactor temperature is controlled at 25°C by water bath circulation; the reactor is shaded to reduce the impact of light on microorganisms.

[0073] The technical parameters and effects of Example 1 are summarized in Table 1.

[0074] Example 2, reference Figure 1 , a partial denitrification coupled anaerobic ammonium oxidation deep denitrification process, comprising the following steps:

[0075] S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is 3:4, and the filling rate is 25%; filled with PVA / PA / ZL gel carrier, the filling rate is 25%;

[0076] S2, NH4 + -N(NH4Cl, 12.5mg·L -1 )、NO3 - -N(NaNO3, 12.5mg·L -1 ) as substrate to start and operate the reactor, using NaAc as carbon source, and controlling the influent COD / TN to 3.0;

[0077] S3, collect inlet and outlet water samples three times a week, and use the national standard method to determine NH4 + -N, NO 2- -N, NO 3- -N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor;

[0078] Average effluent NH4 + -N concentration is 1.7 mg·L -1 ;

[0079] Average outlet NO2 - -N concentration is 0.1 mg·L -1 ;

[0080] Average outlet NO3 - -N concentration is 4.9 mg·L -1 ;

[0081] The TN concentration of the effluent is 6.5 mg·L -1 ;

[0082] The total nitrogen removal rate was 74.0%;

[0083] The average effluent meets the A (first level) standard of urban sewage treatment plant effluent quality standards in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L;

[0084] S4, after the reactor runs stably, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the extracellular polysaccharide (PS) and extracellular protein content (PN), and the sum of PN and PS is the extracellular polymeric substances (EPS) concentration; use Illumina Miseq sequencing platform to test 16s rRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia;

[0085] PN concentration: 29.38 mg g-VSS -1 ;

[0086] PS concentration: 9.61 mg g-VSS -1 ;

[0087] EPS concentration: 38.99 mg g-VSS -1 ;

[0088] Thauera abundance: 2.25%;

[0089] Pseudomonas abundance: 1.01%;

[0090] Candidatus_Brocadia abundance: 2.60%;

[0091] Candidatus_Kuenenia abundance: 1.35%;

[0092] Microorganisms buffer the impact of hydraulic scouring on biofilm by secreting EPS. Typical denitrifying bacteria Thauera and Pseudomonas, as well as anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia all maintain a certain abundance ratio, indicating that the carrier is conducive to the symbiosis of functional microorganisms.

[0093] S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4) reflects the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB;

[0094] Nitrate reduction rate (r NO3 ) is 981.36 mg-N g-VSS -1 ·d -1 ;

[0095] Nitrite generation rate (r NO2 ) is 910.73 mg-N g-VSS -1 ·d -1 ;

[0096] Ammonia nitrogen consumption rate (r NH4 ) is 333.37 mg-N·g-VSS -1 ·d -1 ;

[0097] It can be seen that DNB and AnAOB in the carrier biofilm can respond to environmental shocks synchronously and have good buffering capacity, which has a positive significance for the stable operation of the low-concentration PD / A process, that is, sufficient partial denitrification activity can continuously provide sufficient NO for the Anammox process. 2- -N, thereby enhancing the system's denitrification capacity and maintaining the continuous and stable denitrification of PD / A.

[0098] The PVA / PA / ZL gel carrier in step S1 is a biological carrier with ammonia nitrogen adsorption and desorption function, which is a polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA / ZL loaded with zeolite, with a zeolite loading of 4%, a microbead diameter of 4.0 mm, and a specific surface area of ​​19.0 m 2 ·g -1 , the sedimentation velocity is 255.5m·h -1 ; The equilibrium adsorption capacity Q for ammonia nitrogen calculated by pseudo-second-order kinetics simulation e 0.87 mg·g -1 The maximum adsorption capacity Q of ammonia nitrogen calculated by Langmuir model m 2.30mg·g -1 .

[0099] The reactor in step S2 adopts a UASB reactor system, as shown in the attached Figure 2 As shown, the reactor is cylindrical with a height-to-diameter ratio of 12.5, the water flow path is bottom-in and top-out, an insulation jacket is provided on the outer layer of the reactor, and the reactor temperature is controlled at 30°C by water bath circulation; the reactor is shaded to reduce the impact of light on microorganisms.

[0100] The technical parameters and effects of Example 2 are summarized in Table 1.

[0101] Example 3, reference Figure 1 , a partial denitrification coupled anaerobic ammonium oxidation deep denitrification process, comprising the following steps:

[0102] S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is 3:5, and the filling rate is 30%; filled with PVA / PA / ZL gel carrier, the filling rate is 30%;

[0103] S2, NH4 + -N(NH4Cl, 10mg·L -1 )、NO3 - -N(NaNO3, 10mg·L -1 ) as substrate to start and operate the reactor, using NaAc as carbon source, and controlling the influent COD / TN to 3.0;

[0104] S3, collect inlet and outlet water samples three times a week, and use the national standard method to determine NH4 + -N, NO 2- -N, NO 3- -N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor;

[0105] Average effluent NH4 + -N concentration is 2.0 mg·L -1 ;

[0106] Average outlet NO2 - -N concentration is 0.1 mg·L -1 ;

[0107] Average outlet NO3 - -N concentration is 4.0 mg·L -1 ;

[0108] The TN concentration of the effluent is 6.0 mg·L -1 ;

[0109] The total nitrogen removal rate was 70.0%;

[0110] The average effluent meets the A (first level) standard of urban sewage treatment plant effluent quality standards in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L;

[0111] S4, after the reactor runs stably, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the extracellular polysaccharide (PS) and extracellular protein content (PN), and the sum of PN and PS is the extracellular polymeric substances (EPS) concentration; use Illumina Miseq sequencing platform to test 16s rRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia;

[0112] PN concentration: 28.60 mg g-VSS -1 ;

[0113] PS concentration: 8.33 mg g-VSS -1 ;

[0114] EPS concentration: 36.71 mg g-VSS -1 ;

[0115] Thauera abundance: 2.17%;

[0116] The abundance of Pseudomonas is: 4.59%;

[0117] Candidatus_Brocadia abundance: 2.49%;

[0118] Candidatus_Kuenenia abundance: 0.85%;

[0119] Microorganisms buffer the impact of hydraulic scouring on biofilm by secreting EPS. Typical denitrifying bacteria Thauera and Pseudomonas, as well as anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia all maintain a certain abundance ratio, indicating that the carrier is conducive to the symbiosis of functional microorganisms.

[0120] S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4) reflects the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB;

[0121] Nitrate reduction rate (r NO3 ) is 809.40mg-N·g-VSS -1 ·d -1 ;

[0122] Nitrite generation rate (r NO2 ) is 761.07 mg-N g-VSS -1 ·d -1 ;

[0123] Ammonia nitrogen consumption rate (r NH4 ) is 366.72 mg-N·g-VSS -1 ·d -1 ;

[0124] It can be seen that DNB and AnAOB in the carrier biofilm can respond to environmental shocks synchronously and have good buffering capacity, which has a positive significance for the stable operation of the low-concentration PD / A process, that is, sufficient partial denitrification activity can continuously provide sufficient NO for the Anammox process. 2- -N, thereby enhancing the system's denitrification capacity and maintaining the continuous and stable denitrification of PD / A.

[0125] The PVA / PA / ZL gel carrier in step S1 is a biological carrier with ammonia nitrogen adsorption and desorption function, which is a polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA / ZL loaded with zeolite, with a zeolite loading of 5%, a microbead diameter of 4.0 mm, and a specific surface area of ​​15.4 m 2 ·g -1 , the sedimentation velocity is 261.7 m·h -1 ; The equilibrium adsorption capacity Q for ammonia nitrogen calculated by pseudo-second-order kinetics simulation e 0.90mg·g -1 The maximum adsorption capacity Q of ammonia nitrogen calculated by Langmuir model m 2.53 mg·g -1 .

[0126] The reactor in step S2 adopts a UASB reactor system, as shown in the attached Figure 2 As shown, the reactor is cylindrical with a height-to-diameter ratio of 13, the water flow path is bottom-in and top-out, an insulation jacket is provided on the outer layer of the reactor, and the reactor temperature is controlled at 32°C by water bath circulation; the reactor is shaded to reduce the impact of light on microorganisms.

[0127] The technical parameters and effects of Example 3 are summarized in Table 1.

[0128] Example 4, reference Figure 1 , a partial denitrification coupled anaerobic ammonium oxidation deep denitrification process, comprising the following steps:

[0129] S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is 2:4, and the filling rate is 25%; filled with PVA / PA / ZL gel carrier, the filling rate is 25%;

[0130] S2, NH4 + -N(NH4Cl, 7.5mg·L -1 )、NO3 - -N(NaNO3,7.5mg·L -1 ) as substrate to start and operate the reactor, using NaAc as carbon source, and controlling the influent COD / TN to 4.0;

[0131] S3, collect inlet and outlet water samples three times a week, and use the national standard method to determine NH4 + -N, NO2 - -N, NO3 - -N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor;

[0132] Average effluent NH4 + -N concentration is 2.8 mg·L -1 ;

[0133] Average outlet NO2 - -N concentration is 1.3 mg·L -1 ;

[0134] Average outlet NO3 - -N concentration is 3.4 mg·L -1 ;

[0135] The TN concentration of the effluent was 7.4 mg·L -1 ;

[0136] The total nitrogen removal rate was 50.7%;

[0137] The average effluent meets the A (first level) standard of urban sewage treatment plant effluent quality standards in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L;

[0138] S4, after the reactor runs stably, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the extracellular polysaccharide (PS) and extracellular protein content (PN), and the sum of PN and PS is the extracellular polymeric substances (EPS) concentration; use Illumina Miseq sequencing platform to test 16s rRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia;

[0139] PN concentration: 34.26 mg g-VSS -1 ;

[0140] PS concentration: 14.37 mg g-VSS -1 ;

[0141] EPS concentration: 48.63 mg g-VSS -1 ;

[0142] Thauera abundance: 2.19%;

[0143] The abundance of Pseudomonas is: 3.29%;

[0144] Candidatus_Brocadia abundance: 3.19%;

[0145] Candidatus_Kuenenia abundance: 0.54%;

[0146] Microorganisms buffer the impact of hydraulic scouring on biofilm by secreting EPS. Typical denitrifying bacteria Thauera and Pseudomonas, as well as anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia all maintain a certain abundance ratio, indicating that the carrier is conducive to the symbiosis of functional microorganisms.

[0147] S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4) reflects the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB;

[0148] Nitrate reduction rate (r NO3 ) is 1506.58 mg-N·g-VSS -1 ·d -1 ;

[0149] Nitrite generation rate (r NO2 ) is 1170.41 mg-N g-VSS -1 ·d -1 ;

[0150] Ammonia nitrogen consumption rate (r NH4 ) is 538.43 mg-N·g-VSS -1 ·d -1 ;

[0151] It can be seen that DNB and AnAOB in the carrier biofilm can respond to environmental shocks synchronously and have good buffering capacity, which has a positive significance for the stable operation of the low-concentration PD / A process, that is, sufficient partial denitrification activity can continuously provide sufficient NO for the Anammox process. 2- -N, thereby enhancing the system's denitrification capacity and maintaining the continuous and stable denitrification of PD / A.

[0152] The PVA / PA / ZL gel carrier in step S1 is a biological carrier with ammonia nitrogen adsorption and desorption function, which is a polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA / ZL loaded with zeolite, with a zeolite loading of 6%, a microbead diameter of 5.0 mm, and a specific surface area of ​​13.8 m 2 ·g -1 , the sedimentation rate is 274.2m·h -1 ; The equilibrium adsorption capacity Q for ammonia nitrogen calculated by pseudo-second-order kinetics simulation e 0.94 mg·g -1 The maximum adsorption capacity Q of ammonia nitrogen calculated by Langmuir model m 2.76 mg·g -1 .

[0153] The reactor in step S2 adopts a UASB reactor system, as shown in the attached Figure 2 As shown, the reactor is cylindrical with a height-to-diameter ratio of 15, the water flow path is bottom-in and top-out, an insulation jacket is provided on the outer layer of the reactor, and the reactor temperature is controlled at 35°C by water bath circulation; the reactor is shaded to reduce the impact of light on microorganisms.

[0154] The technical parameters and effects of Example 4 are summarized in Table 1.

[0155] Comparative Example 1 A partial denitrification coupled anaerobic ammonium oxidation denitrification process based on a PVA / PA gel carrier comprises the following steps:

[0156] S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is 2:3, and the filling rate is 20%; filled with PVA / PA gel carrier, the filling rate is 20%;

[0157] S2, NH4 + -N(NH4Cl, 20mg·L -1 )、NO3 - -N(NaNO3, 20mg·L -1 ) as substrate to start and operate the reactor, using NaAc as carbon source, and controlling the influent COD / TN to 2.5;

[0158] S3, collect inlet and outlet water samples three times a week, and use the national standard method to determine NH4 + -N, NO 2- -N, NO 3- -N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor;

[0159] Average effluent NH4 + -N concentration is 5.5 mg·L -1 ;

[0160] Average outlet NO2 - -N concentration is 1.4 mg·L -1 ;

[0161] Average outlet NO3 - -N concentration is 9.2 mg·L -1 ;

[0162] The average effluent TN concentration is 15.8 mg·L -1 ;

[0163] The total nitrogen removal rate was 60.5%;

[0164] The average effluent exceeds the A (first level) standard for urban sewage treatment plant effluent quality in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L;

[0165] S4, after the reactor runs stably, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the extracellular polysaccharide (PS) and extracellular protein content (PN), and the sum of PN and PS is the extracellular polymeric substances (EPS) concentration; use Illumina Miseq sequencing platform to test 16s rRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia;

[0166] PN concentration: 23.38 mg g-VSS -1 ;

[0167] PS concentration: 14.51 mg g-VSS -1 ;

[0168] EPS concentration: 37.89 mg g-VSS -1 ;

[0169] Thauera abundance: 0.16%;

[0170] Pseudomonas abundance: 0.17%;

[0171] Candidatus_Brocadia abundance: 1.91%;

[0172] Candidatus_Kuenenia abundance: 1.06%;

[0173] The EPS secreted by microorganisms was less than that in Example 1 under the same influent and operating conditions; the abundance of typical partial denitrifying bacteria Thauera and Pseudomonas, and anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia were also lower than that in Example 1 under the same influent and operating conditions;

[0174] S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4 ) reflects the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB;

[0175] Nitrate reduction rate (r NO3 ) is 607.90mg-N·g-VSS -1 ·d -1 ;

[0176] Nitrite generation rate (r NO2 ) is 503.78mg-N·g-VSS -1 ·d -1 ;

[0177] Ammonia nitrogen consumption rate (r NH4 ) is 348.02mg-N·g-VSS -1 ·d -1 ;

[0178] It can be seen that the activities of DNB and AnAOB in the carrier biofilm are lower than those in Example 1 under the same influent and operating conditions.

[0179] The biological carrier without ammonia nitrogen adsorption and desorption function in step S1 is polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA, with a microbead diameter of 3.0 mm and a specific surface area of ​​35.9 m 2 ·g -1 , the sedimentation velocity is 233.6m·h -1 The equilibrium adsorption capacity (Q e ) is 0.06 mg·g -1 The maximum adsorption capacity of ammonia nitrogen (Q m ) is 0.09 mg·g -1 Compared with the above-mentioned embodiment, it basically does not have the performance of nitrogen adsorption.

[0180] The reactor in step S2 adopts UASB reactor system, as shown in the attached Figure 2 As shown, the reactor is cylindrical with a height-to-diameter ratio of 10, the water flow path is bottom-in and top-out, an insulation jacket is provided on the outer layer of the reactor, and the reactor temperature is controlled at 25°C by water bath circulation; the reactor is shaded to reduce the impact of light on microorganisms.

[0181] The technical parameters and effects of Comparative Example 1 are summarized in Table 1.

[0182] Comparative Example 2, a partial denitrification coupled anaerobic ammonium oxidation denitrification process based on a PVA / PA gel carrier, comprising the following steps:

[0183] S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is 3:4, and the filling rate is 25%; filled with PVA / PA gel carrier, the filling rate is 25%;

[0184] S2, NH4 + -N(NH4Cl, 12.5mg·L -1 )、NO3 - -N(NaNO3, 12.5mg·L -1 ) as substrate to start and operate the reactor, using NaAc as carbon source, and controlling the influent COD / TN to 3.0;

[0185] S3, collect inlet and outlet water samples three times a week, and use the national standard method to determine NH4 + -N, NO 2- -N, NO 3- -N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor;

[0186] Average effluent NH4 + -N concentration is 3.9 mg·L -1 ;

[0187] Average outlet NO2 - -N concentration is 0.1 mg·L -1 ;

[0188] Average outlet NO3 - -N concentration is 7.5 mg·L -1 ;

[0189] The average TN concentration of the effluent was 12.2 mg·L -1 ;

[0190] The total nitrogen removal rate was 51.2%;

[0191] The average effluent exceeds the A (first level) standard for urban sewage treatment plant effluent quality in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L;

[0192] S4, after the reactor runs stably, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the extracellular polysaccharide (PS) and extracellular protein content (PN), and the sum of PN and PS is the extracellular polymeric substances (EPS) concentration; use Illumina Miseq sequencing platform to test 16s rRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia;

[0193] PN concentration: 19.6 mg g-VSS -1 ;

[0194] PS concentration: 11.45 mg g-VSS -1 ;

[0195] EPS concentration: 30.65mg·g-VSS -1 ;

[0196] Thauera abundance: 0.16%;

[0197] Pseudomonas abundance: 0.31%;

[0198] Candidatus_Brocadia abundance: 1.85%;

[0199] Candidatus_Kuenenia abundance: 1.09%;

[0200] The EPS secretion of microorganisms was less than that of Example 2 under the same influent and operating conditions. The abundance of typical partial denitrifying bacteria Thauera and Pseudomonas, and anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia were also lower than that of Example 2 under the same influent and operating conditions;

[0201] S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4 ) was used to reflect the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB.

[0202] Nitrate reduction rate (r NO3 ) is 760.23 mg-N g-VSS -1 ·d -1 ;

[0203] Nitrite generation rate (r NO2 ) is 610.71 mg-N g-VSS -1 ·d -1 ;

[0204] Ammonia nitrogen consumption rate (r NH4 ) is 306.47 mg-N·g-VSS -1 ·d -1;

[0205] It can be seen that the activities of DNB and AnAOB in the carrier biofilm are lower than those in Example 2 under the same influent and operating conditions.

[0206] The biological carrier without ammonia nitrogen adsorption and desorption function in step S1 is polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA, with a microbead diameter of 3.0 mm and a specific surface area of ​​35.9 m 2 ·g -1 , the sedimentation velocity is 233.6m·h -1 The equilibrium adsorption capacity (Q e ) is 0.06 mg·g -1 The maximum adsorption capacity of ammonia nitrogen (Q m ) is 0.09 mg·g -1 Compared with the above-mentioned embodiment, it basically does not have the performance of nitrogen adsorption.

[0207] The reactor in step S2 adopts UASB reactor system, as shown in the attached Figure 2 As shown, the reactor is cylindrical with a height-to-diameter ratio of 12.5, the water flow path is bottom-in and top-out, an insulation jacket is provided on the outer layer of the reactor, and the reactor temperature is controlled at 30°C by water bath circulation; the reactor is shaded to reduce the impact of light on microorganisms.

[0208] The technical parameters and effects of Comparative Example 2 are summarized in Table 1.

[0209] Comparative Example 3, a partial denitrification coupled anaerobic ammonium oxidation denitrification process based on a PVA / PA gel carrier, comprising the following steps:

[0210] S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is 3:5, and the filling rate is 30%; filled with PVA / PA gel carrier, the filling rate is 30%;

[0211] S2, NH4 + -N(NH4Cl, 10mg·L -1 )、NO3 - -N(NaNO3, 10mg·L -1 ) as substrate to start and operate the reactor, using NaAc as carbon source, and controlling the influent COD / TN to 3.0;

[0212] S3, collect inlet and outlet water samples three times a week, and use the national standard method to determine NH4 + -N, NO 2- -N, NO 3--N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor;

[0213] Average effluent NH4 + -N concentration is 3.4 mg·L -1 ;

[0214] Average outlet NO2 - -N concentration is 0.2 mg·L -1 ;

[0215] Average outlet NO3 - -N concentration is 6.4 mg·L -1 ;

[0216] The average effluent TN concentration is 10.5 mg·L -1 ;

[0217] The total nitrogen removal rate was 47.5%;

[0218] The average effluent exceeds the A (first level) standard for urban sewage treatment plant effluent quality in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L.

[0219] S4, after the reactor runs stably, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the extracellular polysaccharide (PS) and extracellular protein content (PN), and the sum of PN and PS is the extracellular polymeric substances (EPS) concentration; use Illumina Miseq sequencing platform to test 16s rRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia;

[0220] PN concentration: 19.6 mg g-VSS -1 ;

[0221] PS concentration: 7.30 mg g-VSS -1 ;

[0222] EPS concentration: 36.90 mg g-VSS -1 ;

[0223] Thauera abundance: 0.18%;

[0224] Pseudomonas abundance: 0.52%;

[0225] Candidatus_Brocadia abundance: 1.48%;

[0226] Candidatus_Kuenenia abundance: 0.53%;

[0227] The EPS secretion of microorganisms was less than that of Example 3 under the same influent and operating conditions, and the abundance of typical partial denitrifying bacteria Thauera and Pseudomonas, and anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia were also lower than that of Example 3 under the same influent and operating conditions;

[0228] S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4 ) reflects the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB;

[0229] Nitrate reduction rate (r NO3 ) is 569.00mg-N·g-VSS -1 ·d -1 ;

[0230] Nitrite generation rate (r NO2 ) is 523.71 mg-N·g-VSS -1 ·d -1 ;

[0231] Ammonia nitrogen consumption rate (r NH4 ) is 275.98 mg-N·g-VSS -1 ·d -1 ;

[0232] It can be seen that the activities of DNB and AnAOB in the carrier biofilm are lower than those in Example 3 under the same influent and operating conditions.

[0233] The biological carrier without ammonia nitrogen adsorption and desorption function in step S1 is polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA, with a microbead diameter of 3.0 mm and a specific surface area of ​​35.9 m 2 ·g -1 , the sedimentation velocity is 233.6m·h -1 The equilibrium adsorption capacity (Qe ) is 0.06 mg·g -1 The maximum adsorption capacity of ammonia nitrogen (Q m ) is 0.09 mg·g -1 Compared with the above-mentioned embodiment, it basically does not have the performance of nitrogen adsorption.

[0234] The reactor in step S2 adopts UASB reactor system, as shown in the attached Figure 2 As shown, the reactor is cylindrical with a height-to-diameter ratio of 13, the water flow path is bottom-in and top-out, an insulation jacket is provided on the outer layer of the reactor, and the reactor temperature is controlled at 32°C by water bath circulation; the reactor is shaded to reduce the impact of light on microorganisms.

[0235] The technical parameters and effects of Comparative Example 3 are summarized in Table 1.

[0236] Comparative Example 4, a partial denitrification coupled anaerobic ammonium oxidation denitrification process based on a PVA / PA gel carrier, comprising the following steps:

[0237] S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is 2:4, and the filling rate is 25%; filled with PVA / PA gel carrier, the filling rate is 25%;

[0238] S2, NH4 + -N(NH4Cl, 7.5mg·L -1 )、NO3 - -N(NaNO3,7.5mg·L -1 ) as substrate to start and operate the reactor, using NaAc as carbon source, and controlling the influent COD / TN to be 4;

[0239] S3, collect inlet and outlet water samples three times a week, and use the national standard method to determine NH4 + -N, NO 2- -N, NO3 - -N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor;

[0240] Average effluent NH4 + -N concentration is 4.7 mg·L -1 ;

[0241] Average outlet NO2 - -N concentration is 0.5 mg·L -1 ;

[0242] Average outlet NO3 - -N concentration is 5.1 mg·L -1 ;

[0243] The average effluent TN concentration is 10.3 mg·L -1 ;

[0244] The total nitrogen removal rate was 31.3%;

[0245] The effluent exceeds the A (first level) standard for urban sewage treatment plant effluent quality in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L;

[0246] S4, after the reactor runs stably, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the extracellular polysaccharide (PS) and extracellular protein content (PN), and the sum of PN and PS is the extracellular polymeric substances (EPS) concentration; use Illumina Miseq sequencing platform to test 16s rRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia;

[0247] PN concentration: 20.4 mg g-VSS -1 ;

[0248] PS concentration: 10.37 mg g-VSS -1 ;

[0249] EPS concentration: 30.77 mg g-VSS -1 ;

[0250] Thauera abundance: 0.17%;

[0251] Pseudomonas abundance: 0.49%;

[0252] Candidatus_Brocadia abundance: 1.52%;

[0253] Candidatus_Kuenenia abundance: 0.32%;

[0254] The EPS secreted by microorganisms was less than that in Example 4 under the same influent and operating conditions. The abundance of typical partial denitrifying bacteria Thauera and Pseudomonas, and anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia was also lower than that in Example 4 under the same influent and operating conditions.

[0255] S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4 ) reflects the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB;

[0256] Nitrate reduction rate (r NO3 ) is 732.13 mg-N·g-VSS -1 ·d -1 ;

[0257] Nitrite generation rate (r NO2 ) is 608.4mg-N·g-VSS -1 ·d -1 ;

[0258] Ammonia nitrogen consumption rate (r NH4 ) is 237.95mg-N·g-VSS -1 ·d -1 ;

[0259] It can be seen that the activities of DNB and AnAOB in the carrier biofilm are lower than those in Example 4 under the same influent and operating conditions. The biological carrier without ammonia nitrogen adsorption and desorption function in step S1 is polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA, with a microbead diameter of 3.0 mm and a specific surface area of ​​35.9 m 2 ·g -1 , the sedimentation velocity is 233.6m·h -1 The equilibrium adsorption capacity (Q e ) is 0.06 mg·g -1 The maximum adsorption capacity of ammonia nitrogen (Q m ) is 0.09 mg·g -1 Compared with the above-mentioned embodiment, it basically does not have the performance of nitrogen adsorption.

[0260] The reactor in step S2 adopts UASB reactor system, as shown in the attached Figure 2 As shown, the reactor is cylindrical with a height-to-diameter ratio of 15, the water flow path is bottom-in and top-out, an insulation jacket is provided on the outer layer of the reactor, and the reactor temperature is controlled at 35°C by water bath circulation; the reactor is shaded to reduce the impact of light on microorganisms.

[0261] The technical parameters and effects of Comparative Example 4 are summarized in Table 1.

[0262] Table 1 Summary of the PD / A deep denitrification effects of Examples 1-4 and Comparative Examples 1-4

[0263]

[0264]

Claims

1. A partial denitrification coupled anaerobic ammonium oxidation deep denitrification process, characterized in that: The following steps are involved: S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is (2-3): (3-5), the filling rate is 20%-30%; filling PVA / PA / ZL gel carrier, the filling rate is 20-30%; S2, NH4 + -N、NO3 - -N was used as substrate to start and operate the reactor, NaAc was used as carbon source, and the influent COD / TN was controlled at 2.5-4.0; NH4 + -N: 7.5-20mg·L -1 NH4Cl, NO3 - -N: 7.5-20mg·L -1 of NaNO3; S3, collect inlet and outlet water samples more than 3 times a week, and use the national standard method to determine NH4 + -N, NO 2- -N, NO 3- -N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor; S4, after the operation of the reactor is stable, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the extracellular polysaccharide PS (Polysaccharide) and extracellular protein content PN (Protein), the sum of PN and PS is the concentration of extracellular polymer EPS (extracellular polymeric substances); use Illumina Miseq sequencing platform to test 16srRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia; S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4 ) was used to reflect the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB.

2. The process according to claim 1, characterized in that The deep denitrification effect of the step S3 reactor is: Average effluent NH4 + -N concentration is 1.7~3.4mg·L -1 ; Average outlet NO2 - -N concentration is 0.1~1.3mg·L -1 ; Average outlet NO3 - -N concentration is 3.4~6.4mg·L -1 ; The TN concentration of the effluent is 6.0~9.5mg·L -1 ; Total nitrogen removal rate is 50.7-76.3%; The average effluent meets the A (first level) standard of urban sewage treatment plant effluent quality standards in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L.

3. The process according to claim 1, characterized in that In step S4, the extracellular polysaccharide PS (Polysaccharide) and extracellular protein content PN (Protein), PN and PS add up to the extracellular polymer EPS (extracellular polymeric substances) concentration is: PN concentration: 28.60~34.26mg·g-VSS -1 ; PS concentration: 8.33~18.01mg·g-VSS -1 ; EPS concentration: 36.71~48.65mg·g-VSS -1 ; The enrichment effects of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effects of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia are as follows: Thauera abundance: 2.17-2.25%; The abundance of Pseudomonas is: 1.01-4.59%; Candidatus_Brocadia abundance: 2.36-3.19%; Candidatus_Kuenenia abundance: 0.54%~1.44%; Microorganisms buffer the impact of hydraulic scouring on biofilm by secreting EPS. Typical denitrifying bacteria Thauera and Pseudomonas, as well as anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia all maintained their abundance ratios, indicating that the carrier is conducive to the synergistic symbiosis of functional microorganisms.

4. The process according to claim 1, characterized in that The nitrate reduction rate (r) of step S5 NO3 ), nitrite generation rate (r NO2 ), ammonia nitrogen consumption rate (r NH4 )for: Nitrate reduction rate (r NO3 ) is 809.40~1506.58mg-N·g-VSS -1 ·d -1 ; Nitrite generation rate (r NO2 ) is 761.07~1170.41mg-N·g-VSS -1 ·d -1 ; Ammonia nitrogen consumption rate (r NH4 ) is 333.37~538.43mg-N·g-VSS -1 ·d -1 .

5. The process according to claim 1, characterized in that The PVA / PA / ZL gel carrier in step S1 is a biological carrier with ammonia nitrogen adsorption and desorption function, which is a polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA / ZL loaded with zeolite, with a zeolite loading of 2-6%, a microbead diameter of 3.0-5.0 mm, and a specific surface area of ​​13.8-19.0 m 2 ·g -1 , the sedimentation rate is 247.0~274.2m·h -1 ; The equilibrium adsorption capacity Q for ammonia nitrogen calculated by pseudo-second-order kinetics simulation e 0.64~0.94mg·g -1 The maximum adsorption capacity Q of ammonia nitrogen calculated by Langmuir model m 1.03~2.76mg·g -1 .

6. The process according to claim 1, characterized in that The reactor in step S2 adopts a UASB reactor system. The reactor is cylindrical with a height-to-diameter ratio of 10 to 15. The water flow path is bottom-in and top-out. An insulation jacket is provided on the outer layer of the reactor. The reactor temperature is controlled at 25 to 35° C. by water bath circulation. The reactor is shading treated to reduce the impact of light on microorganisms.

7. The process according to claim 1, characterized in that The following steps are involved: S1, using denitrification sludge and Anammox sludge as seed sludge, the inoculation ratio is 2:3, and the filling rate is 20%; filled with PVA / PA / ZL gel carrier, the filling rate is 20%; S2, NH4 + -N、NO3 - -N was used as substrate to start and operate the reactor, NaAc was used as carbon source, and the influent COD / TN was controlled at 2.5; NH4 + -N uses 20mg·L -1 NH4Cl, NO3 - -N uses 20mg·L -1 of NaNO3; S3, collect inlet and outlet water samples three times a week, and use the national standard method to determine NH4 + -N, NO 2- -N, NO 3- -N concentration, the data of the stable period after startup are selected for calculation to evaluate the deep denitrification effect of the reactor; Average effluent NH4 + -N concentration is 3.4 mg·L -1 ; Average outlet NO2 - -N concentration is 0.2 mg·L -1 ; Average outlet NO3 - -N concentration is 6.4 mg·L -1 ; The TN concentration of the effluent is 9.5 mg·L -1 ; The total nitrogen removal rate was 76.3%; The average effluent meets the A (first level) standard of urban sewage treatment plant effluent quality standards in developed areas, that is, TN <10mg / L and NH4 + -N<1~5mg / L; S4, after the operation of the reactor is stable, collect sludge samples, and use anthrone-sulfuric acid spectrophotometer method and Lowry method to determine the content of extracellular polysaccharide (PS) and extracellular protein (PN). The sum of PN and PS is the concentration of extracellular polymeric substances (EPS). Use Illumina Miseq sequencing platform to test 16srRNA sequence analysis of the abundance of functional bacteria in the sludge to evaluate the enrichment effect of typical partial denitrifying bacteria Thauera and Pseudomonas, as well as the enrichment effect of anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia. PN concentration: 30.64 mg g-VSS -1 ; PS concentration: 18.01 mg g-VSS -1 ; EPS concentration: 48.65mg g-VSS -1 ; Thauera abundance: 2.23%; The abundance of Pseudomonas is: 2.58%; Candidatus_Brocadia abundance: 2.36%; Candidatus_Kuenenia abundance: 1.44%; Microorganisms buffer the impact of hydraulic scouring on biofilm by secreting EPS. Typical denitrifying bacteria Thauera and Pseudomonas, as well as anaerobic ammonia oxidizing bacteria Candidatus_Brocadia and Candidatus_Kuenenia all maintain their abundance ratios, indicating that the carrier is conducive to the symbiosis of functional microorganisms. S5, after the reactor runs stably, collect sludge samples, test the partial denitrification activity and Anammox activity of the sludge through experiments, and use the nitrate reduction rate (r NO3 ) and nitrite generation rate (r NO2 ) partial denitrification activity of the reaction sludge, using the ammonia nitrogen consumption rate (r NH4 ) reflects the Anammox activity to evaluate the synergistic metabolic denitrification effect of PDB and AnAOB; Nitrate reduction rate (r NO3 ) is 1085.54 mg-N g-VSS -1 ·d -1 ; Nitrite generation rate (r NO2 ) is 891.71 mg-N g-VSS -1 ·d -1 ; Ammonia nitrogen consumption rate (r NH4 ) is 455.58 mg-N g-VSS -1 ·d -1 ; DNB and AnAOB in the carrier biofilm can respond to environmental shocks synchronously and have good buffering capacity, that is, sufficient partial denitrification activity can continuously provide sufficient NO for the Anammox process. 2- -N, thereby enhancing the system's denitrification capacity and maintaining the continuous and stable denitrification of PD / A.

8. The process according to claim 7, characterized in that The PVA / PA / ZL gel carrier in step S1 is a biological carrier with ammonia nitrogen adsorption and desorption function, which is a polyvinyl alcohol (PVA) and phytic acid (PV) co-crosslinked microbeads PVA / PA / ZL loaded with zeolite, with a zeolite loading of 2%, a microbead diameter of 3.0 mm, and a specific surface area of ​​18.8 m 2 ·g -1 , the sedimentation rate is 247.0m·h -1 ; The equilibrium adsorption capacity Q for ammonia nitrogen calculated by pseudo-second-order kinetics simulation e 0.64 mg·g -1 The maximum adsorption capacity Q of ammonia nitrogen calculated by Langmuir model m 1.03 mg·g -1 .

9. The process according to claim 7, characterized in that The reactor in step S2 adopts a UASB reactor system. The reactor is cylindrical with a height-to-diameter ratio of 10. The water flow path is bottom-in and top-out. An insulation jacket is provided on the outer layer of the reactor. The reactor temperature is controlled at 25°C by water bath circulation. The reactor is shaded to reduce the impact of light on microorganisms.

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