阅读说明：本技术 一种基于mbr的高盐度、高氨氮浓度废水的处理方法 (MBR-based high-salinity high-ammonia-nitrogen-concentration wastewater treatment method ) 是由 王铸 许怀浩 邓岳鹏 李秀英 黄爽秋 胡春 于 2021-07-21 设计创作，主要内容包括：本发明公开了一种基于MBR的高盐度、高氨氮浓度废水的处理方法,涉及废水处理领域。处理方法为：控制进水的盐浓度为废水0w/v％-1w/v％、氨氮浓度为废水的0w/v％-0.003w/v％,控制设备启动所需条件和硝化反应所需碱度；控制废水盐浓度保持不变,分阶段依次提升进水氨氮浓度,分阶段提升的最终进水氨氮浓度至少达到废水的0.1w/v％；控制废水氨氮浓度保持不变,分阶段依次提升进水盐浓度,分阶段提升的最终进水盐浓度至少达到废水的4w/v％。本申请所培养的硝化细菌具有耐高盐度、耐高氨氮浓度能力强的特点,可高效处理废水氨氮浓度达到1000mg/L、盐浓度达到40g/L,出水符合国家标准。(The invention discloses a treatment method of high-salinity and high-ammonia nitrogen concentration wastewater based on MBR, and relates to the field of wastewater treatment. The processing method comprises the following steps: controlling the salt concentration of the inlet water to be 0 w/v% -1 w/v% of the wastewater, controlling the ammonia nitrogen concentration to be 0 w/v% -0.003 w/v% of the wastewater, and controlling the required conditions for starting equipment and the required alkalinity for nitration reaction; controlling the salt concentration of the wastewater to be kept unchanged, and sequentially increasing the ammonia nitrogen concentration of the inlet water by stages, wherein the final ammonia nitrogen concentration of the inlet water increased by stages at least reaches 0.1 w/v% of the wastewater; controlling the ammonia nitrogen concentration of the wastewater to be kept unchanged, and sequentially increasing the concentration of the water inlet salt by stages, wherein the final concentration of the water inlet salt increased by stages at least reaches 4 w/v% of the wastewater. The nitrobacteria cultured by the method has the characteristics of high salinity resistance and high ammonia nitrogen concentration resistance, the ammonia nitrogen concentration of the wastewater can be efficiently treated to reach 1000mg/L, the salt concentration reaches 40g/L, and the effluent meets the national standard.)

1. A treatment method of high salinity and high ammonia nitrogen concentration wastewater based on MBR is characterized in that an MBR membrane bioreactor is adopted for treatment, and comprises the following steps:

s1, starting: the salt concentration of the wastewater inlet condition is 0 w/v% -1 w/v% of the wastewater, the ammonia nitrogen concentration is 0 w/v% -0.003 w/v% of the wastewater, the required conditions for starting the equipment and the required alkalinity of the wastewater nitration reaction are controlled, and the ammonia nitrogen concentration lifting stage can be entered when the ammonia nitrogen removal rate of the outlet water reaches the standard and the operation is stable;

s2, ammonia nitrogen concentration increasing stage: controlling the salt concentration of the wastewater to keep S1 unchanged, sequentially increasing the ammonia nitrogen concentration of the inlet water by stages, wherein the final ammonia nitrogen concentration of the inlet water increased by stages at least reaches 0.1 w/v% of the wastewater, and increasing the ammonia nitrogen concentration of the inlet water or entering a salt concentration increasing stage when the ammonia nitrogen removal rate of the outlet water reaches the standard and the operation is stable;

s3, salt concentration increasing stage: controlling the ammonia nitrogen concentration of the wastewater to keep S2 unchanged, sequentially increasing the concentration of the water inlet salt by stages, wherein the final concentration of the water inlet salt increased by stages at least reaches 4 w/v% of the wastewater, and the concentration of the water inlet salt can be increased when the removal rate of the ammonia nitrogen in the effluent reaches the standard and the operation is stable.

2. The MBR-based high salinity, high ammonia nitrogen concentration wastewater treatment method of claim 1, wherein:

in the S1, the ammonia nitrogen concentration of the water inlet condition is 0.003 w/v% of the wastewater;

in the S2, the ammonia nitrogen concentration of the inlet water is sequentially increased by stages to be 0.006 w/v%, 0.012 w/v%, 0.025 w/v%, 0.05 w/v% and 0.1 w/v%.

3. The MBR-based high salinity, high ammonia nitrogen concentration wastewater treatment method of claim 1, wherein:

in the S1, the salt concentration of the water inlet condition is 1 w/v% of the wastewater;

in the step S3, the concentration of the inlet water salt is sequentially increased to 2 w/v% and 4 w/v% of the wastewater in a staged manner.

4. The MBR-based high salinity, high ammonia nitrogen concentration wastewater treatment method of claim 1, wherein in the S1, S2 and S3, the pH of the wastewater is maintained to be 7-8 all the time.

5. The MBR-based high salinity, high ammonia nitrogen concentration wastewater treatment method of claim 4, wherein: the desired alkalinity of the wastewater in said S1 is derived from NaHCO₃Providing m (NaHCO) in the wastewater₃)：m(NH₄ ⁺-N) is 12.5.

6. The MBR-based high salinity, high ammonia nitrogen concentration wastewater treatment method of claim 1, wherein: in the step S1, the water inlet condition of the wastewater further comprises a phosphorus source with the concentration of 3mg/L, COD concentration of 360mg/L and trace element concentrated solution.

7. The MBR-based high salinity, high ammonia nitrogen concentration wastewater treatment method of claim 6, wherein: the wastewater is artificial simulated wastewater, and the wastewaterThe salt content is provided by NaCl, and the ammonia nitrogen concentration of the wastewater is provided by NH₄Cl, the COD concentration is provided by glucose, and the phosphorus source is KH₂PO₄Provided is a method.

8. The MBR-based high-salinity high-ammonia-nitrogen-concentration wastewater treatment method of claim 6, wherein the preparation method of the trace element concentration solution comprises the following steps: 0.5g H₃BO₃、0.5g ZnCl、0.5g(NH₄)₆Mo₇O₂₄·4H₂O、0.5g NiCl·6H₂O、0.5g AlCl₃·6H₂O、0.5g CoCl₂·6H₂O、0.5g CuSO₄·5H₂O、2g Fe₂(SO₄)₃、1gMnCl₂·4H₂O、5gMgSO₄·7H₂Dissolving O and 5mL of 37 wt% HCl solution in 1000mL of water to obtain a trace element concentrated solution, wherein the addition amount of the trace element concentrated solution in the wastewater is 0.1% of the volume of the wastewater.

9. The MBR-based high salinity, high ammonia nitrogen concentration wastewater treatment method of claim 1, wherein: in the starting condition of S1, the concentration of the inoculated sludge is 10g/L, the hydraulic retention time is 14h, the temperature is controlled to be 15-25 ℃, and the dissolved oxygen is 2-6 mg/L.

10. The MBR-based high salinity, high ammonia nitrogen concentration wastewater treatment method of claim 1, wherein: and the membrane material of the MBR membrane bioreactor is a hollow polyvinylidene fluoride fiber membrane, and the membrane assembly is cleaned under the starting condition of S1 when the transmembrane pressure of the membrane assembly of the MBR is more than 30 kPa.

Technical Field

The invention relates to the technical field of wastewater treatment, in particular to a high-salinity and high-ammonia nitrogen concentration wastewater treatment method based on MBR.

Background

Ammonia is commonly used in industry as an important raw material, resulting in high concentrations of ammonia nitrogen in certain industrial wastewaters. A large amount of high-concentration ammonia nitrogen wastewater can be generated in the production process in the fields of petrifaction, pharmacy, coking, synthetic ammonia, leather making and the like, wherein the ammonia nitrogen concentration of some wastewater can reach 1000 mg/L.

The anaerobic unit series A/O denitrification unit process is a common biological treatment method in industrial wastewater, and a large part of organic carbon source can be consumed when wastewater firstly enters the anaerobic unit uniformly, so that the denitrification unit of the process can possibly face the problems of insufficient carbon source and unqualified total nitrogen removal when the high ammonia nitrogen industrial wastewater is treated. If the high ammonia nitrogen wastewater is subjected to the quality-divided biological pretreatment, namely the wastewater of the high ammonia nitrogen pollution-producing unit is independently collected, the ammonia nitrogen is oxidized into nitrate nitrogen or nitrite nitrogen through the independent nitrification unit, and then the nitrate nitrogen or nitrite nitrogen and other high COD wastewater enter the anaerobic unit, so that the problems of insufficient carbon source and substandard total nitrogen removal can be effectively solved.

However, the high ammonia nitrogen wastewater quality-divided biological pretreatment still faces the following problems: (1) the ammonia nitrogen concentration of the wastewater of the ammonia nitrogen pollution production unit is extremely high, and Free Ammonia (FA) produced by high-concentration ammonia nitrogen has a strong inhibiting effect on nitrifying bacteria; (2) salt is a common industrial raw material, the wastewater of the ammonia nitrogen sewage production unit often has the characteristic of high-concentration salt, and the high-concentration salt can influence nitrifying bacteria; (3) nitrifying bacteria are autotrophic bacteria, and the ammonia nitrogen sewage-producing unit wastewater can not avoid the existence of partial COD, the high-concentration COD can promote the growth and the propagation of heterotrophic bacteria, compete for dissolved oxygen with AOB (ammonia oxidizing bacteria) and NOB (nitrite oxidizing bacteria), and can reduce the proportion of the AOB and the NOB in a microbial community.

Many researches are currently carried out on the biological nitrification process, but the research institute aims at that the ammonia nitrogen concentration of the wastewater is generally low, the tolerance capability of the cultured nitrifying bacteria on the salt concentration and the ammonia nitrogen concentration is low, the effect of treating the wastewater with high salinity and high ammonia nitrogen concentration is poor, and the method has obvious defects and cannot meet the treatment requirements of the wastewater with high salinity and high ammonia nitrogen concentration generated by production units in part of industries.

Disclosure of Invention

The invention provides a high-salinity high-ammonia-nitrogen-concentration wastewater treatment method based on MBR, which overcomes the technical problem of poor effect of treating high-salinity high-ammonia-nitrogen-concentration wastewater in the traditional technology, the cultured nitrifying bacteria have the characteristics of high salinity resistance and high ammonia-nitrogen-concentration resistance, the treatment method can be used for efficiently treating wastewater with the ammonia nitrogen concentration of 1000mg/L and the salt concentration of 40g/L, and the ammonia nitrogen removal rate of the effluent meets the national first-level A standard of urban sewage discharge.

In order to solve the technical problem, the embodiment of the invention provides a treatment method of wastewater with high salinity and high ammonia nitrogen concentration based on MBR, which adopts an MBR membrane bioreactor to treat and comprises the following steps:

s1, starting: the salt concentration of the wastewater inlet condition is 0 w/v% -1 w/v% of the wastewater, the ammonia nitrogen concentration is 0 w/v% -0.003 w/v% of the wastewater, the required conditions for starting the equipment and the required alkalinity of the wastewater nitration reaction are controlled, and the ammonia nitrogen concentration lifting stage can be entered when the ammonia nitrogen removal rate of the outlet water reaches the standard and the operation is stable;

s2, ammonia nitrogen concentration increasing stage: controlling the salt concentration of the wastewater to keep S1 unchanged, sequentially increasing the ammonia nitrogen concentration of the inlet water by stages, wherein the final ammonia nitrogen concentration of the inlet water increased by stages at least reaches 0.1 w/v% of the wastewater, and increasing the ammonia nitrogen concentration of the inlet water or entering a salt concentration increasing stage when the ammonia nitrogen removal rate of the outlet water reaches the standard and the operation is stable;

s3, salt concentration increasing stage: controlling the ammonia nitrogen concentration of the wastewater to keep S2 unchanged, sequentially increasing the concentration of the water inlet salt by stages, wherein the final concentration of the water inlet salt increased by stages at least reaches 4 w/v% of the wastewater, and the concentration of the water inlet salt can be increased when the removal rate of the ammonia nitrogen in the effluent reaches the standard and the operation is stable.

By adopting the scheme, when nitrifying bacteria are adopted to carry out biological nitrification treatment on high-salinity and high-ammonia nitrogen concentration wastewater, the membrane component in the MBR can reduce the loss of sludge and improve the concentration of the sludge, and because the concentration of the sludge is improved and the retention time (SRT) of the sludge is prolonged, the quantity of organic matters borne by unit weight of activated sludge in unit time is reduced, namely the F/M ratio is reduced, thereby being beneficial to the growth and enrichment of the nitrifying bacteria, and improving the impact load resistance of the reactor and the efficiency and stability of a nitrification process; meanwhile, as the ammonia oxidizing bacteria and the nitrite oxidizing bacteria in the nitrifying bacteria are sensitive to pH, the required alkalinity needs to be provided to maintain the adaptive weakly alkaline growth environment, which is beneficial to the propagation of the nitrifying bacteria; in addition, by gradually increasing the ammonia nitrogen concentration and the salt concentration, the ammonia nitrogen is a growth substrate of nitrobacteria, the increase of the ammonia nitrogen concentration is beneficial to the increase of the sludge concentration and the enrichment of nitrifying bacteria groups, the efficient removal of the ammonia nitrogen is ensured in the subsequent salt concentration replacement process, so that the enrichment and the domestication of the nitrified sludge are realized, the finally cultured nitrobacteria have the characteristics of high salinity resistance and high ammonia nitrogen concentration, the ammonia nitrogen concentration of the treated wastewater can reach 1000mg/L at most, the salt concentration can reach 40g/L at most, the ammonia nitrogen removal rate of the effluent meets the national urban sewage discharge first-level A standard, the defects of poor effect, low salt tolerance concentration and low ammonia nitrogen concentration of the cultured nitrobacteria in the aspects of treating the high salinity and high ammonia nitrogen wastewater by the traditional technology are overcome, and the defects of large amount of high salinity, low ammonia nitrogen concentration and the like generated in the production process of the fields of petrifaction, pharmacy, coking, synthetic ammonia, tanning and the like are overcome, The wastewater with high ammonia nitrogen concentration has important practical benefits.

Preferably, in the S1, the ammonia nitrogen concentration of the water inlet condition is 0.003 w/v% of the wastewater; in the S2, the ammonia nitrogen concentration of the inlet water is sequentially increased to 0.006 w/v%, 0.012 w/v%, 0.025 w/v%, 0.05 w/v% and 0.1 w/v% of the wastewater in stages.

Preferably, in the S1, the salt concentration of the water inlet condition is 1 w/v% of the wastewater; in the step S3, the concentration of the inlet water salt is sequentially increased to 2 w/v% and 4 w/v% of the wastewater in a staged manner.

By adopting the above scheme, salt concentration is kept unchanged at the ammonia nitrogen concentration promotion stage, the nitrobacteria are independently acclimated to tolerate the ammonia nitrogen concentration, meanwhile, the ammonia nitrogen concentration is kept unchanged at the salt concentration promotion stage, the nitrobacteria are acclimated to tolerate the salt concentration, and when the ammonia nitrogen removal rate of the effluent index reaches the standard and is kept stable for a long time, the ammonia nitrogen or salt concentration tolerance of the nitrobacteria is improved.

Preferably, the pH of the wastewater is maintained at 7 to 8 at S1, S2 and S3.

Preferably, the desired alkalinity of the wastewater in said S1 is determined by NaHCO₃Providing m (NaHCO) in the wastewater₃)：m(NH₄ ⁺-N) is 12.5.

By adopting the scheme, ammonia nitrogen is firstly oxidized into nitrite nitrogen by Ammonia Oxidizing Bacteria (AOB) in the nitration process, and then Nitrite Oxidizing Bacteria (NOB) are utilized to oxidize nitrite nitrogen into nitrate nitrogen, and as the Ammonia Oxidizing Bacteria (AOB) and the Nitrite Oxidizing Bacteria (NOB) are sensitive to pH change, NaHCO is required to be utilized when wastewater treatment is carried out₃The alkalinity required for the nitration reaction is provided to maintain the pH within the range of 7-8, and the pH outside the range is adjusted with HCl or NaOH to provide a slightly alkaline environment suitable for the growth of nitrifying bacteria.

Preferably, in the step S1, the water inlet condition of the wastewater further includes a phosphorus source with a concentration of 3mg/L, a COD concentration of 360mg/L, and a trace element concentrated solution.

As a preferable scheme, the wastewater is artificial simulated wastewater, the salt content of the wastewater is provided by NaCl, and the ammonia nitrogen concentration of the wastewater is NH₄Cl, the COD concentration is provided by glucose, and the phosphorus source is KH₂PO₄Provided is a method.

Preferably, the preparation method of the trace element concentration solution comprises the following steps: 0.5g H₃BO₃、0.5g ZnCl、0.5g(NH₄)₆Mo₇O₂₄·4H₂O、0.5g NiCl·6H₂O、0.5g AlCl₃·6H₂O、0.5g CoCl₂·6H₂O、0.5g CuSO₄·5H₂O、2g Fe₂(SO₄)₃、1gMnCl₂·4H₂O、5gMgSO₄·7H₂Dissolving O and 5mL of 37 wt% HCl solution in 1000mL of water to obtain a trace element concentrated solution, wherein the addition amount of the trace element concentrated solution in the wastewater is 0.1% of the volume of the wastewater.

Preferably, in the starting condition of S1, the concentration of the inoculated sludge is 10g/L, the hydraulic retention time is 14h, the temperature is controlled to be 15-25 ℃, and the dissolved oxygen is 2-6 mg/L.

By adopting the scheme, the inoculation concentration, the hydraulic retention time, the temperature and the like of the sludge are controlled, the environment suitable for the growth and enrichment of nitrifying bacteria can be provided, and the oxygen saturation coefficients of the ammonia oxidizing bacteria and the nitrite oxidizing bacteria are respectively 0.2-0.4 mg/L and 1.2-1.5 mg/L, so that the dissolved oxygen content of the reactor is controlled to be 2-6 mg/L, and the requirement of the nitrifying process can be met.

Preferably, the membrane material of the MBR membrane bioreactor is a hollow polyvinylidene fluoride fiber membrane, and the membrane module is cleaned under the starting condition of S1 when the transmembrane pressure of the membrane module of the MBR is greater than 30 kPa.

By adopting the scheme, after sludge is intercepted by the membrane component of the MBR for a long time, a large amount of substances can be accumulated on the surface of the membrane component and inside the membrane pore channel, so that water flow is blocked, the water outlet efficiency is influenced, the wastewater treatment efficiency is reduced, the membrane component needs to be cleaned by adopting physical and chemical means, and the transmembrane pressure of the membrane component is ensured to be maintained below 30 kPa.

Compared with the prior art, the embodiment of the invention has the following beneficial effects:

the invention adopts the membrane component in the MBR reactor to intercept the sludge so as to improve the concentration of the sludge, reduce the quantity of organic matters borne by unit weight of activated sludge in unit time, facilitate the growth and enrichment of nitrobacteria, and improve the impact load resistance of the reactor and the efficiency and stability of the nitrification process.

Meanwhile, because ammonia oxidizing bacteria and nitrite oxidizing bacteria in nitrifying bacteria are sensitive to pH, NaHCO is used₃The required alkalinity is provided to maintain the adaptive alkalescent growth environment, which is beneficial to the propagation of nitrifying bacteria.

In addition, the nitrified sludge is enriched and domesticated in a mode of gradually increasing the ammonia nitrogen concentration and the salt concentration, the cultured nitrifying bacteria have the characteristics of high salinity resistance and high ammonia nitrogen concentration, the ammonia nitrogen concentration of the treatable wastewater can reach 1000mg/L at most, and the salt concentration can reach 40g/L at most.

Drawings

FIG. 1: the results of the detection of the concentrations of nitrite nitrogen and nitrate nitrogen in the effluent after the ammonia nitrogen concentration is sequentially increased and in the effluent after the salt concentration is sequentially increased in S3 in the embodiment of the invention are shown in S2.

In the figure, lnfluent NH₄ ⁺-N: ammonia nitrogen concentration; effect NO₂ ^—N: nitrite nitrogen concentration; effect NO₃ ^—N: nitrate nitrogen concentration; NaClcontent: the salt concentration.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The inventor of the application discovers that when the completely stirred tank reactor is used for treating high ammonia nitrogen wastewater with the ammonia nitrogen concentration of 1100mg/L, the removal rate of the reactor to ammonia nitrogen is less than 50% under the condition of insufficient alkalinity; the short-cut nitrification of the high ammonia nitrogen wastewater is processed by adopting an airlift reactor, and when the ammonia nitrogen concentration of the inlet water reaches 1400mg/L (ammonia nitrogen load is 2.1 gNH)₄ ⁺The removal rate of ammonia nitrogen in the reactor can be maintained to be more than 91 percent even if the reactor is used for removing ammonia nitrogen in the N/L.d), but the sludge loss is aggravated due to the increase of aeration quantity, which means that the problem of sludge loss is solvedAnd alkalinity can be increased, and the ammonia nitrogen concentration and ammonia nitrogen load of inlet water can be improved.

A Membrane Bioreactor (MBR) is a sewage treatment process combining a membrane separation technology and an activated sludge process, the MBR can avoid the loss of sludge due to the interception effect of a membrane component on the sludge, the sludge concentration of the MBR can be controlled by the complete separation of the Sludge Retention Time (SRT) and the Hydraulic Retention Time (HRT), so that the sludge concentration in the reactor can be improved as much as possible, the extension of the SRT and the reduction of the F/M ratio (the ratio of organic matters to microorganism content) are more beneficial to the growth and enrichment of autotrophic nitrifying bacteria, the impact load resistance of the reactor is improved, the efficiency and the stability of the nitrification process are improved, and the MBR has remarkable advantages in the aspect of high-concentration ammonia nitrogen wastewater treatment.

Further research shows that when the ammonia nitrogen concentration of inlet water reaches 1500mg/L, the ammonia nitrogen load is 1.44g NH₄ ⁺When the ammonia nitrogen concentration is-N/L.d, the dissolved oxygen in the MBR is controlled to be more than 2.5mg/L, and the ammonia nitrogen can be removed by more than 93 percent; when the concentration of the inlet ammonia nitrogen reaches 2000mg/L and the load of the inlet ammonia nitrogen is 2.0gNH₄ ⁺And when the ammonia nitrogen concentration is-N/L.d, the removal rate of the MBR to the ammonia nitrogen stably reaches more than 99 percent, which shows that the MBR has good nitrification capability when treating the high ammonia nitrogen wastewater.

Preparation example

A microelement concentrate is prepared by the following method: 0.5g H₃BO₃、0.5g ZnCl、0.5g(NH₄)₆Mo₇O₂₄·4H₂O、0.5g NiCl·6H₂O、0.5g AlCl₃·6H₂O、0.5g CoCl₂·6H₂O、0.5g CuSO₄·5H₂O、2g Fe₂(SO₄)₃、1gMnCl₂·4H₂O、5gMgSO₄·7H₂Dissolving O and 5mL of 37 wt% HCl solution in 1000mL of water to obtain the trace element concentrated solution.

Examples

A method for treating wastewater with high salinity and high ammonia nitrogen concentration based on MBR adopts an immersed MBR membrane bioreactor, the total volume is 13.5L, and the effective volume is10L, the membrane material is a hollow polyvinylidene fluoride fiber membrane (aperture is 0.03 μm, inner diameter of membrane is 1.0mm, outer diameter is 2.2mm, membrane area is 0.235m²) The membrane module outlet is communicated with the suction pump through a pump pipe and is used for realizing constant-flow water outlet, a pressure sensor is arranged between the membrane module and the suction pump and is used for recording the transmembrane pressure change of the membrane module in the running process in real time, and the processing method specifically comprises the following steps:

s1, starting: the control equipment starts the required conditions and the required alkalinity of waste water, starts the MBR reactor, adopts artificial simulation waste water, and the condition of intaking of control waste water is: the salt concentration is 10g/L, the ammonia nitrogen concentration is 30mg/L, COD concentration is 360mg/L, meanwhile, a phosphorus source with the concentration of 3mg/L and a trace element concentrated solution with the volume of 0.1 percent of the wastewater, which are required by the growth of microorganisms, are added, and NaHCO is added₃Maintaining the alkalinity needed by the wastewater during the nitration reaction, then using HCl or NaOH to adjust the pH of the wastewater to be always kept at 7-8, the operation time is 1 st day-28 th day, taking the ammonia nitrogen concentration of the effluent as an index, and entering an ammonia nitrogen load lifting stage when the ammonia nitrogen removal rate of the effluent reaches more than 99% and the reactor operates stably for a long time;

s2, ammonia nitrogen concentration increasing stage: on the basis of adapting to the salt concentration of 10g/L, other operation conditions are not changed, the ammonia nitrogen concentration of wastewater inlet water is increased from 30mg/L to 60mg/L on the 29 th day, and the operation time is 29 th to 39 th days; the ammonia nitrogen concentration of the wastewater inlet water is increased from 60mg/L to 120mg/L on the 40 th day, and the running time is from the 40 th day to the 56 th day; the ammonia nitrogen concentration of the wastewater inlet water is increased from 120mg/L to 250mg/L on the 57 th day, and the operation time is from the 57 th day to the 71 th day; the ammonia nitrogen concentration of the wastewater inlet water is increased from 250mg/L to 500mg/L on the 72 th day, and the operation time is from the 72 th day to the 117 th day; the ammonia nitrogen concentration of the wastewater inlet water is increased from 500mg/L to 1000mg/L on the 118 th day, and the operation time is from the 118 th day to the 178 th day; meanwhile, in the process of increasing the ammonia nitrogen concentration each time, HCl or NaOH is adopted to adjust the pH value to be 7-8 so as to maintain the corresponding alkalinity, the ammonia nitrogen concentration of the effluent is taken as an index, and when the ammonia nitrogen removal rate of the effluent reaches more than 99 percent and the reactor runs stably for a long time, the ammonia nitrogen concentration of the influent wastewater can be increased again or the salt concentration increasing stage is carried out;

s3, salt concentration increasing stage: on the basis of adapting to the ammonia nitrogen concentration of 1000mg/L, other operation conditions are not changed, the concentration of wastewater inlet water salt is increased from 10g/L to 20g/L on the 179 th day, and the operation time is 179 th day to 202 th day; the salt concentration of the wastewater inlet water is increased from 20g/L to 40g/L on the 203 th day, and the operation time is from the 203 th day to the 225 th day; meanwhile, in the process of increasing the salt concentration each time, HCl or NaOH is adopted to adjust the pH value to be 7-8 so as to maintain the corresponding alkalinity, the ammonia nitrogen concentration of the effluent is taken as an index, and when the ammonia nitrogen removal rate of the effluent reaches more than 99 percent and the reactor runs stably for a long time, the influent salt concentration of the wastewater can be increased again.

Wherein the salt concentration of the wastewater in S1, S2 and S3 is provided by NaOH, and the ammonia nitrogen concentration is provided by NH₄Cl, COD concentration from glucose, phosphorus source from KH₂PO₄The microelement concentrate is prepared by the preparation example.

NaHCO in the alkalinity needed for controlling the wastewater of S1₃The addition amount of (C) is according to m (NaHCO) in the wastewater₃)：m(NH₄ ⁺-N) was added at a ratio of 12.5.

In the conditions required by starting of the control equipment of S1, controlling the dissolved oxygen of the reactor to be 2mg/L-6mg/L by adopting blast aeration, controlling the concentration of inoculated sludge (MLSS) to be 10g/L, controlling the temperature condition to be 20 +/-5 ℃, controlling the Hydraulic Retention Time (HRT) to be 14h, and not discharging sludge in the experimental period, wherein the inoculated sludge is from the return sludge of a long secondary sedimentation tank for common urban sewage treatment, and is preferably from a sewage treatment plant with high-efficiency ammonia nitrogen removal capability; meanwhile, controlling the transmembrane pressure of the membrane component to be not more than 30kPa, and if the transmembrane pressure displayed by the pressure sensor is more than 30kPa, cleaning by adopting the following method:

s01, taking the membrane module out of the MBR for physical cleaning, and washing a filter cake layer on the surface of the membrane module by hydraulic flushing;

s02, chemically cleaning the membrane module to remove substances attached to the surface of the membrane and in the pore channels of the membrane, placing the membrane module in a special cleaning box, adding a sodium hypochlorite solution with the mass fraction of 3%, covering and sealing the membrane module, placing the membrane module in a constant-temperature shaking table at 30 ℃, performing oscillation reaction for 6 hours under the condition of 50r/min, and then taking out the membrane module and washing residual sodium hypochlorite by using clean water;

s03, putting the membrane module into a cleaning box again, adding a sulfuric acid solution with the mass fraction of 3%, sealing the membrane module after covering the membrane module, putting the membrane module into a constant-temperature shaking table at the temperature of 30 ℃, shaking the membrane module for 8 hours under the condition of 50r/min, taking out the membrane module, and clearly washing residual sulfuric acid, namely putting the membrane module into an MBR (membrane bioreactor) for reuse;

s04, when the membrane module needs to be stored for a long time, the membrane module is placed in a sulfuric acid solution with the mass fraction of 1.5% for storage.

According to the invention, nitrifying bacteria are adopted to carry out biological nitrification treatment on the wastewater with high salinity and high ammonia nitrogen concentration, a membrane component in the MBR reactor is utilized to intercept sludge, the daily sludge discharge amount is zero under the condition of not carrying out manual sludge discharge, the sludge loss is avoided, and the sludge concentration in the reactor is improved as much as possible; meanwhile, under the condition of the same influent water quality and hydraulic retention time, the concentration of the sludge is increased and the retention time (SRT) of the sludge is prolonged, so that the quantity of organic matters borne by the activated sludge in unit weight in unit time is reduced, namely the F/M ratio is reduced, the growth and enrichment of autotrophic nitrifying bacteria are facilitated, and the impact load resistance of the reactor and the efficiency and stability of a nitrification process are improved.

The nitrifying bacteria adopted in the nitrifying process mainly comprise Ammonia Oxidizing Bacteria (AOB) and Nitrite Oxidizing Bacteria (NOB), ammonia nitrogen is firstly oxidized into nitrite nitrogen by the Ammonia Oxidizing Bacteria (AOB), and then the Nitrite Oxidizing Bacteria (NOB) is utilized to oxidize the nitrite nitrogen into nitrate nitrogen. Since nitrifying bacteria are more sensitive to pH changes and Nitrite Oxidizing Bacteria (NOB) are more sensitive to pH than Ammonia Oxidizing Bacteria (AOB), the use of NaHCO is required for wastewater treatment₃To provide the alkalinity required for the nitration reaction while maintaining the pH in the range of 7-8 to provide a weakly alkaline environment suitable for the growth of nitrifying bacteria.

Meanwhile, enrichment and domestication of nitrified sludge are carried out by gradually increasing the ammonia nitrogen concentration and the salt concentration, ammonia nitrogen is a growth substrate of nitrifying bacteria, the increase of the ammonia nitrogen concentration is beneficial to the increase of the sludge concentration and the enrichment of nitrifying bacteria groups, the efficient removal of ammonia nitrogen is ensured in the subsequent salt concentration replacement process, finally, nitrified activated sludge which can treat wastewater with high ammonia nitrogen concentration and high salt concentration and control the removal rate of ammonia nitrogen in effluent to reach more than 99.5% and stably run for a long time is obtained, the maximum ammonia nitrogen concentration of the treated wastewater can reach 1000mg/L, and the maximum salt concentration can reach 40 g/L. Meanwhile, nitrite oxidizing bacteria NOB are more sensitive to ammonia nitrogen concentration than AOB, if the removal rate of ammonia nitrogen is insufficient, the high ammonia nitrogen concentration in the reactor can possibly inhibit NOB activity, and the stability of the nitration process is influenced, so the removal rate of the selected effluent ammonia nitrogen reaches 99%, and in addition, the ammonia oxidizing bacteria AOB has high substrate affinity to ammonia nitrogen, and the removal rate of the ammonia nitrogen under the condition of normal operation of the reactor can reach more than 99%.

The treatment method overcomes the defects of poor effect, salt concentration tolerance of cultured nitrobacteria, low ammonia nitrogen concentration and the like when the high salinity and high ammonia nitrogen concentration wastewater is treated by the traditional technology, and has important practical benefits for treating a large amount of high salinity and high ammonia nitrogen concentration wastewater generated in the production process in the fields of petrifaction, pharmacy, coking, synthetic ammonia, leather making and the like.

Effect verification:

firstly, ammonia nitrogen removal rate: through detecting the ammonia nitrogen concentration of the final effluent of S3 in the embodiment, the ammonia nitrogen removal rate of the effluent obtained by calculation reaches more than 99.5 percent, reaches the national first-level A standard of municipal sewage discharge, and the equipment can stably operate for a long time, thereby realizing the high-efficiency treatment of the wastewater with high salinity and high ammonia nitrogen concentration.

Secondly, nitrite nitrogen and nitrate nitrogen content: by detecting the contents of nitrite nitrogen and nitrate nitrogen in the effluent water with the sequentially increased ammonia nitrogen concentration in the embodiment S2 and the effluent water with the sequentially increased salt concentration in the embodiment S3, the detection results are shown in FIG. 1, and after the ammonia nitrogen concentration or the salt concentration of the wastewater inlet water is increased each time, the nitrite nitrogen concentration of the effluent water is temporarily increased, because Nitrite Oxidizing Bacteria (NOB) are sensitive to the change of environmental factors, the nitrite nitrogen oxidizing effect is poor in the short time of environmental change; but then the NOB can quickly recover the high-efficiency oxidation of nitrite nitrogen, so that nitrogen elements in the effluent mainly exist in the form of nitrate nitrogen; the nitrifying bacteria cultured by the scheme of the invention have strong tolerance to salt concentration and ammonia nitrogen concentration, can efficiently treat wastewater with high salinity and high ammonia nitrogen concentration, and has the highest salt concentration reaching 40g/L and the ammonia nitrogen concentration reaching 1000 mg/L. In addition, when the final salt concentration of the reactor was raised to 40g/L and kept stable in S3, the salt concentration was again raised to 70g/L and the reactor crashed.

The above-mentioned embodiments are provided to further explain the objects, technical solutions and advantages of the present invention in detail, and it should be understood that the above-mentioned embodiments are only examples of the present invention and are not intended to limit the scope of the present invention. It should be understood that any modifications, equivalents, improvements and the like, which come within the spirit and principle of the invention, may occur to those skilled in the art and are intended to be included within the scope of the invention.