A method for treating phenol-ammonia wastewater

Abstract

The present application relates to a kind of phenol ammonia wastewater treatment methods, comprising the following steps: (1) biological carrier and sludge are mixed, and biological carrier-sludge mixture is obtained;(2) pretreatment: to biological carrier-sludge mixture step-by-step adding ammonia-containing wastewater containing organic carbon source carries out step-by-step reaction, the organic carbon source includes non-phenolic organic carbon source and phenolic organic matter, in each step reaction, the content of non-phenolic organic carbon source is constant or reduces, and the content of phenolic organic matter is constant or increases;(3) when the concentration of phenol in ammonia-containing wastewater added in step-by-step reaction is 90%-100% of the concentration of phenol in the phenol ammonia wastewater to be treated, the pretreatment is completed;(4) adding phenol ammonia wastewater is handled.The present application is by controlling dissolved oxygen concentration and gradient, and the content of phenol is improved to form high-quality biological carrier-sludge mixed solution, realize phenol oxidizing bacteria, ammonia-oxidizing bacteria, nitrite oxidizing bacteria, anaerobic ammonia-oxidizing bacteria and denitrifying bacteria's symbiosis, and then realize the simultaneous removal of phenol ammonia.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wastewater treatment, and particularly relates to a treatment method of phenol-ammonia wastewater. BACKGROUND

[0002] Phenols are toxic organic compounds and have been listed as priority pollutants in many countries. If not properly treated, phenols can cause harm to the environment and human health. Phenols exist in large amounts in ammonia-rich wastewater discharged by the coal chemical industry. In 2020, the total amount of industrial wastewater discharged in China was about 17.72 billion tons, more than 50% of which came from the coal chemical industry (including coal-to-natural gas, coal-to-olefins, coal liquefaction, coal-to-ethylene glycol, etc.). Therefore, the treatment of coal chemical wastewater rich in phenols and ammonia is a key point in the treatment of industrial wastewater in China.

[0003] Coal chemical wastewater has the dual difficulties of high phenol toxicity and high ammonia nitrogen concentration. At present, the treatment mode of "oil removal-phenol and ammonia recovery-biochemical treatment-deep treatment" is basically adopted for coal chemical wastewater in China. After physical and chemical oil removal, ammonia stripping and extraction phenol removal, the biochemical unit still faces the stress of high concentration of phenols and ammonia (the concentrations of phenol and ammonia are still as high as 250-350 mg / L and 200-400 mg / L, respectively). Phenols can inhibit nitrification. In order to remove phenols and ammonia, the current equipment mostly adopts a process of detoxification treatment (anaerobic / aerobic degradation of phenols) combined with multi-stage A / O (nitrification-denitrification for nitrogen removal). Phenols are detoxified by anaerobic / aerobic degradation before the nitrification unit, and high-concentration NH4 + -N is removed through the nitrification-denitrification pathway, but the nitrification process requires a large amount of aeration for oxygen supply, and the denitrification process requires additional carbon source. This process has technical limitations such as high energy and chemical consumption, large sludge production, and long process flow.

[0004] Therefore, it is urgent to develop an intensive biochemical treatment method for phenol and ammonia wastewater with the advantages of energy saving and emission reduction. SUMMARY

[0005] In order to solve the above technical problems, the present application provides a treatment method of phenol and ammonia wastewater, which controls the dissolved oxygen concentration and gradient to improve the content of phenols and form a high-quality biological carrier-sludge mixed solution, realizes the synergistic symbiosis of phenol-oxidizing bacteria, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, anaerobic ammonia-oxidizing bacteria and denitrifying bacteria, and makes the sensitive denitrifying bacteria immune to the toxic inhibition of phenols, thereby realizing the simultaneous removal of phenol and ammonia wastewater. This method has the advantages of saving aeration energy consumption, less carbon source dosage, low sludge production, and less greenhouse gas emission.

[0006] In a first aspect, the present application provides a treatment method of phenol and ammonia wastewater, which comprises the following steps:

[0007] (1) mixing a biological carrier and sludge to obtain a biological carrier-sludge mixture;

[0008] (2) Pretreatment: stepwise adding ammonia-containing wastewater containing an organic carbon source to the above-mentioned biological carrier-sludge mixture to perform stepwise reaction, to obtain a stepwise reaction liquid, wherein:

[0009] The organic carbon source includes non-phenolic organic carbon source and phenolic organic matter, and in each step of reaction, the content of the non-phenolic organic carbon source in the ammonia-containing wastewater is unchanged or reduced, and the content of the phenolic organic matter is unchanged or increased;

[0010] (3) When the concentration of phenol in the ammonia-containing wastewater added in the stepwise reaction is 90%-100% of the concentration of phenol in the phenol-ammonia wastewater to be treated, the pretreatment is completed;

[0011] (4) Adding phenol-ammonia wastewater for treatment;

[0012] The sludge includes anaerobic ammonia oxidation sludge, nitrification sludge and denitrification sludge;

[0013] The concentration of dissolved oxygen needs to be controlled to be 0-0.3 mg / L, for example, 0.05 mg / L, 0.1 mg / L, 0.15 mg / L, 0.2 mg / L, 0.25 mg / L, etc. during the stepwise reaction of step (2) and the treatment of step (4).

[0014] The concentration of phenol in the ammonia-containing wastewater of step (3) can be 92%, 94%, 96%, 98%, etc. of the concentration of phenol in the phenol-ammonia wastewater to be treated.

[0015] The treatment method of phenol-ammonia wastewater provided by the present application forms a high-quality biological carrier-sludge mixed solution by controlling the concentration and gradient of dissolved oxygen and increasing the content of phenol, realizes the synergistic symbiosis of phenol-oxidizing bacteria, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, anaerobic ammonia-oxidizing bacteria and denitrifying bacteria with different oxygen requirements, and makes sensitive denitrifying bacteria immune to the toxic inhibition of phenol, thereby realizing the simultaneous removal of phenol and ammonia. The method has the advantages of saving aeration energy consumption, less carbon source dosage, low sludge yield and less greenhouse gas emission. The treatment method provided by the present application has the following advantages: after pretreatment, the abundances of typical POB (phenol-oxidizing bacteria), DNB (denitrifying bacteria), AOB (ammonia-oxidizing bacteria), AnAOB (anaerobic ammonia-oxidizing bacteria) and NOB (nitrite-oxidizing bacteria) in the sludge reach 27.52-31.09%, 16.33-23.42%, 2.21-4.06%, 2.60-3.56% and 0.31-0.67% respectively. Specifically:

[0016] The present application needs to be pretreated before treating phenolic ammonia wastewater, and the content of phenols is gradually increased in the pretreatment process through step-by-step reaction, that is, in each reaction, the content of non-phenolic organic carbon source in ammonia-containing wastewater is controlled to be unchanged or reduced, and the content of phenolic organic matter is controlled to be unchanged or increased, so that a small amount of phenols in the initial stage reaction system is degraded under the action of heterotrophic bacteria (phenol-oxidizing bacteria and denitrifying bacteria), and the microorganism bacteria, especially ammonia-oxidizing bacteria and anaerobic ammonia-oxidizing bacteria, are exempted from the toxic inhibition of phenols. At the same time, the concentration of dissolved oxygen is strictly controlled within 0-0.3 mg / L, a DO (dissolved oxygen) concentration gradient is formed from the outside to the inside of the biofilm, and the microorganism bacteria are allowed to grow on the surface of the biological carrier based on the biological carrier, which promotes the symbiotic biofilm microenvironment of phenol-oxidizing bacteria, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, anaerobic ammonia-oxidizing bacteria and denitrifying bacteria with different oxygen demands, gradually adapts to the concentration of phenol in the phenol ammonia wastewater to be treated, and the degradation of phenol by heterotrophic bacteria (phenol-oxidizing bacteria and denitrifying bacteria) in the biofilm protects the sensitive denitrifying bacteria in the sludge from the toxic inhibition of phenol, and the low concentration of dissolved oxygen effectively inhibits the nitrite-oxidizing bacteria, which is beneficial to the low-carbon and low-energy autotrophic denitrification of ammonia-oxidizing bacteria and anaerobic ammonia-oxidizing bacteria, and further realizes simultaneous nitrification-anaerobic ammonia oxidation-denitrification, so as to achieve the purpose of simultaneous phenol removal and denitrification of phenol ammonia wastewater, improve the treatment effect of phenol ammonia wastewater, and provide a new technical choice for the treatment of phenol ammonia wastewater (such as coking, semicoke and other coal chemical industry wastewater).

[0017] The properties of the sludge in step (1) are shown in Table 1 below:

[0018] Table 1 Composition and activity of sludge

[0019] Name VSS (mg / L) Sludge activity / g-N / VSS / d Nitrifying sludge 1100 0.26 Anammox sludge 2031 0.43 Denitrifying sludge 1368 0.39

[0020] As a preferred technical solution of the present application, the sludge in step (1) contains phenol-oxidizing bacteria, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, anaerobic ammonia-oxidizing bacteria and denitrifying bacteria.

[0021] As a preferred technical solution of the present application, the biological carrier in step (1) is selected from PVA / PA / Fe or PVA / PA porous gel particles.

[0022] The PVA / PA / Fe is a polyvinyl alcohol / phytic acid / iron porous gel particle, and the PVA / PA is a polyvinyl alcohol / phytic acid porous gel particle. The biological carrier provided by the present application has a flexible network porous structure and can be prepared by a chemical crosslinking method.

[0023] The preparation method of the PVA / PA / Fe porous gel particle is as follows:

[0024] ① Dissolution of polyvinyl alcohol: Add 300 mL of deionized water and 46.8 g of polyvinyl alcohol powder to a 500 mL beaker equipped with a mechanical stirrer, and dissolve under mechanical stirring for 12.0 h to obtain a polyvinyl alcohol aqueous solution with a mass percentage of 15.6%;

[0025] ② Dissolution of sodium phytate and ferrous sulfate: Add 1.95g of sodium phytate and 1.95g of ferrous sulfate to a polyvinyl alcohol aqueous solution at the same time, and continue mechanical stirring for 0.5h until completely dissolved;

[0026] ③ NaOH-activated polyvinyl alcohol mixture: Take 90 mL of 5% NaOH solution and add it to the polyvinyl alcohol mixture that is being stirred and has been completely dissolved. Continue stirring for 0.5 h. With the addition of NaOH solution, the mass percentages of sodium phytate, ferrous sulfate and polyvinyl alcohol are diluted from 0.65%, 0.65% and 15.6% to 0.5%, 0.5% and 12.0%, respectively, and a sodium phytate-ferrous sulfate-polyvinyl alcohol gel solution is obtained.

[0027] ④ Chemical crosslinking: Add 2g of CaCl2 to 100mL of 4% boric acid solution and stir evenly to prepare a chemical crosslinking agent; use a syringe to evenly drop the above sodium phytate-ferrous sulfate-polyvinyl alcohol gel solution into the above chemical crosslinking agent while stirring continuously and rapidly; place in the chemical crosslinking agent for crosslinking for 72h, remove, and wash several times with distilled water until the pH is neutral to obtain the PVA / PA / Fe porous gel particles for use.

[0028] The method for preparing the PVA / PA porous gel particles is as follows:

[0029] ① Dissolution of polyvinyl alcohol: Add 300 mL of deionized water and 46.8 g of polyvinyl alcohol powder to a 500 mL beaker equipped with a mechanical stirrer, and dissolve under mechanical stirring for 12.0 h to obtain a polyvinyl alcohol aqueous solution with a mass percentage of 15.6%;

[0030] ② Dissolution of phytic acid: Add 1.95g of phytic acid to the polyvinyl alcohol aqueous solution and continue mechanical stirring for 0.5h until completely dissolved;

[0031] ③ NaOH-activated polyvinyl alcohol mixture: Take 90 mL of 5% NaOH solution and add it to the polyvinyl alcohol mixture that is being stirred and has been completely dissolved. Continue stirring for 0.5 h. With the addition of NaOH solution, the mass percentages of phytic acid and polyvinyl alcohol are diluted from 0.65%, 0.65% and 15.6% to 0.5%, 0.5% and 12.0%, respectively, and a sodium phytate-ferrous sulfate-polyvinyl alcohol gel solution is obtained.

[0032] ④ Chemical crosslinking: Add 2g of CaCl2 to 100mL of 4% boric acid solution and stir evenly to prepare a chemical crosslinking agent; use a syringe to evenly drop the above phytic acid-polyvinyl alcohol gel solution into the above chemical crosslinking agent while stirring continuously and rapidly; place in the chemical crosslinking agent for crosslinking for 72h, remove, and wash several times with distilled water until the pH is neutral to obtain the PVA / PA porous gel particles for use.

[0033] The properties of the biological carrier described in this invention are shown in Table 2 below:

[0034] Table 2 Properties of biological carriers

[0035]

[0036] The amount of microbial attachment mentioned in Table 2 refers to the amount of microbial attachment on the biological carrier in the biological carrier-sludge mixed solution obtained after the pretreatment of this invention.

[0037] As a preferred technical solution of the present invention, the stepwise reaction in step (2) is carried out in a reaction tank, and the filling volume of the biological carrier is 1 / 4 to 1 / 3 of the effective volume of the reaction tank.

[0038] The effective volume of the reaction tank in this invention refers to the volume of liquid in the reaction tank. When pretreatment is performed, the effective volume of the reaction tank includes the total volume of the biological carrier, sludge, and ammonia-containing wastewater.

[0039] As a preferred technical solution of the present invention, the stepwise reaction in step (2) is carried out in a reaction tank, and the filling volume of the sludge is 1 / 5 to 1 / 4 of the effective volume of the reaction tank.

[0040] As a preferred technical solution of the present invention, the reaction time of each step in the stepwise reaction in step (2) is 11-23h, for example 12h, 14h, 16h, 18h, 20h, 22h, etc.

[0041] This invention requires a gradual increase in the concentration of phenolic organic matter during pretreatment. Excessive reaction time in each step increases costs and reduces treatment efficiency, while insufficient reaction time prevents bacteria from adapting to the phenolic organic matter concentration, leading to reduced phenol and ammonia removal. Once the total nitrogen removal rate (TNRE) and / or COD (chemical oxygen demand) removal rate (CRE) in the treated wastewater reach an optimal level (TNRE and / or CRE ≥ 80%), the treatment time can be appropriately shortened to improve treatment efficiency.

[0042] As a preferred technical solution of the present invention, after obtaining the stepwise reaction solution in step (2), the stepwise reaction solution is further subjected to static standing and drainage.

[0043] As a preferred technical solution of the present invention, after the stepwise reaction solution is allowed to stand, the supernatant is tested. When the total nitrogen removal rate is ≥80% and / or the COD removal rate is ≥80%, in the next reaction step, the content of non-phenolic organic carbon sources in the ammonia-containing wastewater is reduced and the content of phenolic organic matter in the ammonia-containing wastewater is increased.

[0044] In the pretreatment process of this invention, the concentration of phenolic organic matter needs to be gradually increased. When the total nitrogen removal rate (TNRE) and / or COD removal rate (CRE) in the stepwise reaction solution reach a relatively optimal level (TNRE and / or CRE ≥ 80%), it indicates that the microorganisms in the system have adapted to the current concentration of phenol in the ammonia-containing wastewater. In the next reaction step, the content of phenolic organic matter can be appropriately increased and the content of non-phenolic organic carbon sources can be reduced, so that the microorganisms in the system gradually adapt to the concentration of phenol in the phenol-ammonia wastewater to be treated.

[0045] In the initial stage of pretreatment in this invention, the lower the content of phenolic organic matter in the ammonia-containing wastewater, the better; otherwise, it will have a strong toxic inhibitory effect on anaerobic ammonia-oxidizing bacteria (AnAOB) and autotrophic bacteria such as synergistic ammonia-oxidizing bacteria (AOB).

[0046] As a preferred embodiment of the present invention, in the stepwise reaction, the concentration of the phenolic organic matter in the ammonia-containing wastewater in the first step reaction is 0 mg / L.

[0047] As a preferred embodiment of the present invention, in the stepwise reaction, the organic carbon source in the first step reaction is a non-phenolic organic carbon source, and the COD value of the non-phenolic organic carbon source in the ammonia-containing wastewater is 90%-100% of the COD value of phenol in the phenol-ammonia wastewater to be treated, for example, 92%, 94%, 96%, 98%, etc.

[0048] The COD value of the non-phenolic organic carbon source in the ammonia-containing wastewater mentioned in this invention refers to the COD value converted from the concentration of the non-phenolic organic carbon source in the ammonia-containing wastewater; the COD value of phenol in the phenol-ammonia wastewater to be treated refers to the COD value converted from the concentration of phenol in the phenol-ammonia wastewater to be treated.

[0049] In the initial stage of pretreatment, this invention requires the provision of a non-phenolic organic carbon source with a COD equivalent of 90%-100% of the COD equivalent of phenol in the phenol-ammonia wastewater to be treated. On the one hand, if the phenol concentration in the wastewater is high, the content of the non-phenolic organic carbon source in the initial stage needs to be correspondingly high. This is because the pretreatment method provided by this invention requires gradually increasing the concentration of phenolic organic matter in the ammonia-containing wastewater. If the content of the non-phenolic organic carbon source in the initial stage is too low, sufficient carbon source cannot be provided during the stepwise reaction process. On the other hand, if the phenol concentration in the wastewater is low, the content of the non-phenolic organic carbon source in the initial stage can be correspondingly low, because only a small number of stepwise reaction microorganisms are needed to adapt to the phenol concentration in the wastewater, and energy consumption can be reduced while treatment efficiency is improved. It is understood that if the biological carrier-sludge mixture solution obtained after pretreatment by this invention can treat phenol-ammonia wastewater with a high phenol content, it can also be used to treat phenol-ammonia wastewater with a lower phenol content.

[0050] As a preferred embodiment of the present invention, in the stepwise reaction, when the content of non-phenolic organic carbon sources in the ammonia-containing wastewater is reduced, the concentration of the non-phenolic organic carbon sources in the ammonia-containing wastewater is reduced by 10-100 mg / L compared with the previous step, for example, 20 mg / L, 30 mg / L, 40 mg / L, 50 mg / L, 60 mg / L, 70 mg / L, 80 mg / L, 90 mg / L, etc., preferably 50-70 mg / L.

[0051] As a preferred embodiment of the present invention, in the stepwise reaction, when the content of phenolic organic matter in the ammonia-containing wastewater is increased, the concentration of the phenolic organic matter in the ammonia-containing wastewater increases by 10-100 mg / L compared with the previous step, for example, 20 mg / L, 30 mg / L, 40 mg / L, 50 mg / L, 60 mg / L, 70 mg / L, 80 mg / L, 90 mg / L, etc., preferably 10-50 mg / L.

[0052] When the content of phenolic organic matter in ammonia-containing wastewater is increased, if the increase is too small, the microbial bacteria will be more adaptable but the treatment efficiency will be too low. If the increase is too large, it may have a toxic inhibitory effect on autotrophic bacteria such as anaerobic ammonia oxidizing bacteria (AnAOB) and ammonia oxidizing bacteria (AOB) in the system.

[0053] As a preferred technical solution of the present invention, the non-phenolic organic carbon source in step (2) is selected from any one or a combination of at least two of sodium acetate, glucose or starch.

[0054] As a preferred technical solution of the present invention, the phenolic organic compound in step (2) is selected from any one or a combination of at least two of phenol, cresol, aminophenol, nitrophenol, naphthol or chlorophenol.

[0055] As a preferred embodiment of the present invention, the concentration of dissolved oxygen is controlled by aeration, and aeration and non-aeration are alternated. Preferably, the aeration time is 4-6 minutes each time and the non-aeration time is 5-6 minutes each time.

[0056] In one specific embodiment of the present invention, in the stepwise reaction of the pretreatment, the aeration time and non-aeration time of the first step reaction are both controlled at 5 minutes. The aeration time and non-aeration time of subsequent stepwise reactions are adjusted according to the effluent data of the stepwise reaction solution in the previous step. The specific adjustment strategy is shown in Table 3 below:

[0057] Table 3

[0058] No. NH4 + -N eff ]]> NO2 - -N eff ]]> NO3 - -N eff ]]> Aeration time Non-aeration time 1 >5 mg / L >5 mg / L >5 mg / L Unchanged Extended by 1 min 2 <5 mg / L >5 mg / L >5 mg / L Shortened by 1 min Unchanged 3 >5 mg / L <5 mg / L >5 mg / L Extended by 1 min Extended by 1 min 4 >5 mg / L >5 mg / L <5 mg / L Extended by 1 min Unchanged 5 <5 mg / L <5 mg / L >5 mg / L Shortened by 1 min Extended by 1 min 6 <5 mg / L >5 mg / L <5 mg / L Shortened by 0.5 min Unchanged 7 >5 mg / L <5 mg / L <5 mg / L Extended by 1 min Unchanged

[0059] The shortening and lengthening mentioned in Table 3 are all based on a 5-minute timeframe. That is, shortening by 1 minute is equivalent to shortening by 1 minute from a 5-minute timeframe, resulting in 4 minutes; lengthening by 1 minute is equivalent to extending by 1 minute from a 5-minute timeframe, resulting in 6 minutes.

[0060] This invention does not impose excessive limitations on the aeration intensity during aeration, ensuring that the aeration intensity within the range of dissolved oxygen concentration in the system is within the protection scope of this invention.

[0061] In one specific embodiment of the present invention, the initial aeration intensity is 80 mL / min. The aeration intensity is adjusted by real-time monitoring of dissolved oxygen concentration. If the dissolved oxygen concentration reaches the upper limit of 0.3 mg / L, the aeration intensity is reduced (the aeration volume is reduced by 5 mL / min) to ensure that low DO (dissolved oxygen) effectively inhibits NOB (nitrite oxidizing bacteria).

[0062] As a preferred technical solution of the present invention, the stepwise reaction in step (2) is carried out under stirring, and the stirring rate is preferably 10-70 r / min, such as 20 r / min, 30 r / min, 40 r / min, 50 r / min, 60 r / min, etc.

[0063] As a preferred embodiment of the present invention, the stirring rod used for stirring is a single-blade auger structure.

[0064] As a preferred embodiment of the present invention, the pitch-to-outer-diameter ratio of the stirring rod is 3 / 8.

[0065] As a preferred embodiment of the present invention, the length of the stirring rod is 2 / 3 of the liquid height in the reaction tank.

[0066] The present invention does not impose too many limitations on the effective volume of the reaction tank. The larger the effective volume, the more wastewater can be treated each time, and the higher the treatment efficiency. As a preferred technical solution of the present invention, the effective volume of the reaction tank is 75%-90% of the volume of the reaction tank, such as 78%, 80%, 82%, 84%, 86%, 88%, etc.

[0067] The stirring rod provided by the present invention can agitate the mixture of biological carrier and microbial sludge to fill the reaction tank with less hydraulic disturbance, thereby improving the mass transfer efficiency in the reaction tank.

[0068] As a preferred embodiment of the present invention, the settling time is 30-50 minutes, such as 35 minutes, 40 minutes, 45 minutes, etc.

[0069] After obtaining the stepwise reaction solution, the present invention needs to allow it to stand so that the biological carrier and sludge settle to the bottom of the reaction tank.

[0070] As a preferred embodiment of the present invention, the water exchange rate during drainage is 1 / 2 to 2 / 3.

[0071] In this invention, the concentration of phenolic organic matter is increased by stepwise reaction gradient during pretreatment. When the total nitrogen removal rate (TNRE) and / or COD removal rate (CRE) in the stepwise reaction solution reach a better level (TNRE and / or CRE ≥ 80%), the treatment efficiency can be improved by appropriately adjusting and increasing the water exchange rate.

[0072] As a preferred embodiment of the present invention, the drainage time is 10-20 minutes, such as 12 minutes, 14 minutes, 16 minutes, 18 minutes, etc.

[0073] After the pretreatment is completed, phenol and ammonia wastewater can be added to the reaction tank for treatment. After the treated water is discharged, phenol and ammonia wastewater can be added again, which is continuous, efficient, energy-saving and emission-reducing.

[0074] As a preferred technical solution of the present invention, in step (4), the filling volume of the biological carrier is 1 / 4 to 1 / 3 of the effective volume of the reaction tank.

[0075] As a preferred technical solution of the present invention, in step (4), the filling volume of the sludge is 1 / 5 to 1 / 4 of the effective volume of the reaction tank.

[0076] The effective volume of the reaction tank in this invention refers to the volume of liquid in the reaction tank. When treating phenol and ammonia wastewater, the effective volume of the reaction tank includes the total volume of the biological carrier, the sludge, and the liquid of the phenol and ammonia wastewater.

[0077] As a preferred technical solution of the present invention, the processing time in step (4) is 11-23 hours, such as 12 hours, 14 hours, 16 hours, 18 hours, 20 hours, 22 hours, etc.

[0078] The treatment method provided by this invention can continuously treat phenol and ammonia wastewater. When the total nitrogen removal rate (TNRE) and / or COD removal rate (CRE) in the treated phenol and ammonia wastewater reaches a better level (TNRE and / or CRE ≥ 80%), the treatment time can be appropriately adjusted and shortened to improve the treatment efficiency of phenol and ammonia wastewater.

[0079] As a preferred technical solution of the present invention, the concentration of dissolved oxygen is controlled by aeration during the treatment in step (4). The aeration and non-aeration are alternated, preferably with an aeration time of 4-6 minutes and a non-aeration time of 5-6 minutes.

[0080] As a specific embodiment of the present invention, in the treatment method of the present invention, the aeration time and non-aeration time are both controlled to be 5 minutes when treating phenol and ammonia wastewater for the first time. The aeration time and non-aeration time in subsequent continuous treatment of phenol and ammonia wastewater are adjusted according to the effluent data of phenol and ammonia wastewater after the previous treatment. The specific adjustment strategy is shown in Table 3.

[0081] This invention does not impose excessive limitations on the aeration intensity during aeration, ensuring that the aeration intensity within the range of dissolved oxygen concentration in the system is within the protection scope of this invention.

[0082] In one specific embodiment of the present invention, the initial aeration intensity of the first treatment of phenol and ammonia wastewater is 80 mL / min. The aeration intensity is adjusted by real-time monitoring of dissolved oxygen concentration. If the dissolved oxygen concentration reaches the upper limit of 0.3 mg / L, the aeration intensity is reduced (the aeration volume is reduced by 5 mL / min) to ensure that low DO (dissolved oxygen) effectively inhibits NOB (nitrite oxidizing bacteria).

[0083] As a preferred technical solution of the present invention, the processing in step (4) also requires stirring. The stirring rate is preferably 10-70 r / min, such as 20 r / min, 30 r / min, 40 r / min, 50 r / min, 60 r / min, etc.

[0084] As a preferred technical solution of the present invention, the stirring rod used in step (4) is a single-blade auger structure.

[0085] As a preferred technical solution of the present invention, the pitch-to-outer-diameter ratio of the stirring rod in step (4) is 3 / 8.

[0086] As a preferred technical solution of the present invention, the length of the stirring rod in step (4) is 2 / 3 of the liquid height in the reaction tank.

[0087] The present invention does not impose too many limitations on the effective volume of the reaction tank. The larger the effective volume, the more phenol and ammonia wastewater can be treated each time. As a preferred technical solution of the present invention, the effective volume of the reaction tank is 75%-90% of the volume of the reaction tank, such as 78%, 80%, 82%, 84%, 86%, 88%, etc.

[0088] The stirring device provided by the present invention can agitate the mixture of biological carrier and microbial sludge to fill the reaction tank with less hydraulic disturbance, thereby improving the mass transfer efficiency in the reaction tank.

[0089] As a preferred technical solution of the present invention, step (4) further includes settling and effluent discharge of the phenol-ammonia wastewater.

[0090] As a preferred embodiment of the present invention, the settling time is 30-50 minutes, such as 35 minutes, 40 minutes, 45 minutes, etc.

[0091] After the phenol-ammonia wastewater is treated, the present invention performs sedimentation so that the biological carrier and sludge settle to the bottom of the reaction tank.

[0092] As a preferred embodiment of the present invention, the water exchange rate during water discharge is 1 / 2 to 2 / 3.

[0093] As a preferred embodiment of the present invention, the water outlet time is 10-20 minutes, such as 12 minutes, 14 minutes, 16 minutes, 18 minutes, etc.

[0094] The treatment method provided by this invention can continuously treat phenol and ammonia wastewater. After sedimentation and effluent discharge, the wastewater can be fed back into the reaction tank for the next cycle of phenol and ammonia wastewater treatment. This method is continuous, efficient, energy-saving, and reduces emissions. When the total nitrogen removal rate (TNRE) and / or COD removal rate (CRE) of the treated phenol and ammonia wastewater reaches an optimal level (TNRE and / or CRE ≥ 80%), appropriately adjusting and increasing the water exchange rate can further improve the treatment efficiency of phenol and ammonia wastewater.

[0095] As a preferred technical solution of the present invention, the concentration of phenol in the phenol-ammonia wastewater in step (4) is 0-500 mg / L, such as 5 mg / L, 10 mg / L, 50 mg / L, 100 mg / L, 150 mg / L, 200 mg / L, 250 mg / L, 300 mg / L, 350 mg / L, 400 mg / L, 450 mg / L, etc., preferably 0-230 mg / L.

[0096] As a preferred technical solution of the present invention, the concentration of ammonia in the phenol-ammonia wastewater in step (4) is 0-500 mg / L.

[0097] The phenol and ammonia wastewater treatment method provided by this invention can simultaneously remove phenol and ammonia wastewater with phenol concentrations of 0-500 mg / L and ammonia concentrations of 0-500 mg / L. Furthermore, after the treated wastewater is discharged, phenol and ammonia wastewater can be added again, which is continuous, efficient, energy-saving, and emission-reducing.

[0098] This invention does not impose excessive limitations on the apparatus for treating phenol and ammonia wastewater; any apparatus that can achieve the purpose of treating phenol and ammonia wastewater according to this invention can be used in this invention.

[0099] As a specific embodiment of the present invention, the present invention also provides a phenol and ammonia wastewater treatment device, the device comprising an inlet tank, an SBR reaction tank and an outlet tank connected to each other, the SBR reaction tank being provided with a stirring device and an aeration device, a first pipe for pumping phenol and ammonia wastewater being provided outside the inlet tank and the SBR reaction tank, and a second pipe for pumping solution being provided outside the outlet tank and the SBR reaction tank.

[0100] The aeration device includes an aeration pump, a probe, and an aeration controller.

[0101] The stirring device includes a stirring motor, an auger-type stirring paddle, and a stirring timer. The upper part is an electric gearbox controlled by a timed switching power supply. The lower stirring rod is a single-blade auger structure with a pitch-to-outer-diameter ratio of 3 / 8. The length of the auger is 2 / 3 of the effective liquid height. The stirring device is controlled by a controller to start and stop the stirring. The controller starts the stirring after the water intake is completed and stops the stirring when the treatment stage is completed.

[0102] The first and second pipelines are respectively equipped with inlet valves and outlet valves, as well as inlet and outlet timers. The inlet and outlet water are controlled by the valves, and the valves are set with the inlet and outlet water times by the controller. One operating cycle includes: inlet stage (10 min); treatment stage (11-23 h), during which continuous stirring and intermittent aeration are controlled; settling stage (30-50 min); and outlet stage (10-20 min).

[0103] The apparatus for treating phenol and ammonia wastewater is as follows: Figure 1 As shown, where:

[0104] SBR reactor: It contains built-in biological carriers and sludge, serving as the reaction site for the biological removal of phenol and ammonia wastewater;

[0105] Stirring device: The stirring speed is used to regulate the mixing and mass transfer effect of the carrier, sludge and wastewater in the reactor;

[0106] Inlet and outlet water system: Based on the treatment effect of the reaction tank, the intermittent cycle of water inflow and outflow of the reaction tank is automatically controlled by valves; the phenol and ammonia removal process operation includes "inlet-treatment-sedimentation-effluent", specifically as follows: Figure 2 As shown;

[0107] Aeration device: The dissolved oxygen (DO) level in the reactor is metered and controlled according to the substrate consumption and product formation in the biochemical reaction. The DO level in the reactor is monitored in real time by a DO probe, and the aeration intensity is adjusted accordingly. This promotes the synergistic symbiosis of phenol-oxidizing bacteria, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, anaerobic ammonia-oxidizing bacteria, and denitrifying bacteria, achieving simultaneous removal of phenols and ammonia.

[0108] The technical solution provided by the embodiments of the present invention has the following advantages compared with the prior art:

[0109] (1) The phenol and ammonia wastewater treatment method provided by the present invention forms a high-quality biological carrier-sludge mixed solution by controlling the dissolved oxygen concentration and gradient increasing the phenol content, thereby achieving the synergistic symbiosis of phenol oxidizing bacteria, ammonia oxidizing bacteria, nitrite oxidizing bacteria, anaerobic ammonia oxidizing bacteria and denitrifying bacteria with different DO requirements.

[0110] (2) The phenol and ammonia wastewater treatment method provided by the present invention protects sensitive denitrifying bacteria from the toxic inhibition of phenol, thereby achieving the simultaneous removal of phenol and ammonia. This method has advantages such as saving aeration energy consumption, low carbon source addition, low sludge production and low greenhouse gas emissions. Attached Figure Description

[0111] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0112] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0113] Figure 1 The apparatus for treating phenol and ammonia wastewater provided by the present invention, wherein:

[0114] I. SBR reactor; II. Agitation device (1. Agitator motor, 2. Screw agitator, 3. Agitator timer); III. Inlet and outlet water device (4. Outlet water tank, 5. Inlet water tank, 6. Outlet water valve, 7. Inlet water valve, 8. Inlet and outlet water timer); IV. Aeration device (9. DO probe, 10. Aeration pump, 11. Aeration controller).

[0115] Figure 2 This is a schematic diagram of the phenol and ammonia removal process provided by the present invention;

[0116] Figure 3 This is a diagram illustrating the treatment effect of phenol and ammonia wastewater according to Embodiment 1 of the present invention.

[0117] Figure 4 This is a diagram showing the distribution of microbial diversity in the carrier biofilm obtained in Example 1 of the present invention.

[0118] Figure 5 This is a diagram illustrating the effect of phenol and ammonia wastewater treatment according to Embodiment 2 of the present invention.

[0119] Figure 6 This is a diagram showing the distribution of microbial diversity in the carrier biofilm obtained in Example 2 of the present invention. Detailed Implementation

[0120] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0121] Many specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the invention, and not all embodiments.

[0122] The embodiments provided by this invention all utilize the phenol and ammonia wastewater treatment device described in this invention, combined with... Figure 1 It is known that the device includes an inlet tank 5, an SBR reaction tank I and an outlet tank 4 that are connected to each other. The SBR reaction tank I is also equipped with a stirring device II and an aeration device IV. The inlet tank 5 and the SBR reaction tank I are provided with a first pipe for pumping phenol and ammonia wastewater, and the outlet tank 4 and the SBR reaction tank I are provided with a second pipe for pumping solution.

[0123] The aeration device II includes an aeration pump 10, a probe 9, and an aeration controller 11;

[0124] The stirring device II includes a stirring motor 1, an auger-type stirring paddle 2, and a stirring timer 3;

[0125] The first pipe and the second pipe are respectively equipped with an inlet valve 7 and an outlet valve 6, as well as an inlet / outlet timer 8.

[0126] During operation, ammonia-containing wastewater or phenol-ammonia wastewater enters the SBR reaction tank I through the inlet tank 5. During the reaction, the stirring device II is used for stirring and the aeration device IV is used for intermittent aeration. After the reaction is completed, the wastewater is discharged into the effluent tank after settling, thus completing one operating cycle.

[0127] Example 1

[0128] This embodiment provides a method for treating phenol and ammonia wastewater, including the following steps:

[0129] During reactor operation, the reaction time for each cycle is allocated as follows: 10 min for influent, 11-23 h for stirring and aeration, 40 min for settling, and 10 min for effluent discharge. The stirring rate is 20 r / min, and the dissolved oxygen (DO) concentration during aeration is controlled at 0-0.3 mg / L. The water exchange rate during effluent discharge is 1 / 2-2 / 3. By gradually increasing the phenol concentration, the microorganisms gradually adapt to the phenol stress. After the effluent stabilizes in one stage, the phenol concentration is increased, and the treatment effect is adjusted by controlling the DO concentration. The specific steps are as follows:

[0130] (1) Place 1 L PVA / PA biological carrier (properties of biological carrier are shown in Table 2) and 0.6 L sludge (properties of sludge are shown in Table 1) in the SBR reactor.

[0131] (2) Start the treatment device and add ammonia-containing wastewater containing sodium acetate into the reaction tank through the inlet tank. The ammonia concentration is 500 mg / L and the sodium acetate concentration in the ammonia-containing wastewater is 640 mg / L, so that the effective volume of the reaction tank is 3L, and carry out the first step of the reaction. In the first step of the reaction, aeration and non-aeration were alternated, with each aeration and non-aeration time being 5 minutes. After 23 hours of reaction, the mixture was allowed to stand for 40 minutes, and then drained for 10 minutes, with a water exchange rate of 1 / 2. The water quality was then tested. After four consecutive step-by-step reactions, the effluent stabilized (total nitrogen removal rate ≥80%). In the next step, phenol was added to the influent, with a phenol concentration of 11.5 mg / L in the ammonia-containing wastewater, and the sodium acetate concentration was reduced to 577 mg / L. After 16 consecutive cycles, the effluent stabilized (total nitrogen removal rate ≥80% and / or COD (chemical oxygen demand) removal rate ≥80%). In the next step, the phenol concentration in the influent was increased to 23 mg / L, and the sodium acetate concentration was reduced to 513 mg / L. After several step-by-step reactions, the phenol concentration increased until all sodium acetate in the influent was replaced by phenol. At this point, the phenol concentration reached 230 mg / L, equivalent to a COD (chemical oxygen demand) of 500 mg / L. Meanwhile, the effluent quality was measured after each reaction step, and the aeration time and intensity of the next step were adjusted according to the substrate conditions (as shown in Table 3). The DO probe was used for real-time monitoring. When the DO reached the set upper limit of 0.3 mg / L during real-time aeration, the aeration intensity was automatically reduced (the aeration rate was reduced by 5 mL / min).

[0132] (3) Phenolic and ammonia wastewater with a phenol concentration of 230 mg / L and an ammonia concentration of 500 mg / L is introduced for treatment.

[0133] After treatment, the total nitrogen removal rate (TNRE) of the phenol-ammonia wastewater was measured to be 84.82±2.78%, and the COD removal rate (CRE) was 87.8±1.08%. Specific influent and effluent data and treatment effects are as follows:Figure 3 As shown.

[0134] This embodiment also tested the biological carrier and sludge after treating the phenol and ammonia wastewater. It was found that the biological carrier effectively attached microorganisms, with a microbial attachment rate of 3.14 ± 0.26 g VSS / L. At this time, the EPS of the carrier biofilm was measured to be 70.34 ± 4.15 mg g. -1 VSS -1 The EPS of the initial inoculated sludge was 54.32 ± 3.75 mg g. -1 VSS -1 .

[0135] Based on the biodiversity detection of microorganisms using 16S rRNA, the phyla that were most abundant in the sludge after the treatment of phenol and ammonia wastewater were Proteobacteria (58%), Cgloroflexi (11%), Bacteroidetes (10%), and Planctomycetes (10%), totaling 90%. The abundance distribution of typical functional bacterial genera is summarized as follows: Nitrosomonas (Nitrosomonas genus) belonging to AOB 2.21%; Nitrospira (Nitrospira genus) belonging to NOB 0.31%; Candidatus_Kuenenia (Candidatus_Kuenenia genus) and Candidatus_Brocadia (Candidatus_Brocadia genus) belonging to AnAOB 2.57% and 0.03%, totaling 2.6%; Thaurea (Thauera genus) 2.97%, Denitrosoma 5.69%, Limnobacter (Lake Sedimentary Bacterium) 0.99%, PHOS-HE36 5.19%, Ottowia (Ottowia genus) 1.38%, and Azoarcus (Azoarcus genus) 0.11%, totaling 16.33%, belonging to DNB. The genera of bacteria (POBs) involved in the degradation of phenol and its intermediate metabolites (organic acids) are: WPS-2 19.99%, SBR103 19.38%, and A4b 1.72%, totaling 31.09%. The distribution of microbial diversity in the carrier biofilm is shown in the figure below. Figure 4 As shown.

[0136] As can be seen, this embodiment successfully achieved the synergistic symbiosis of POB, AOB, NOB, DNB and AnAOB, and effectively treated phenol and ammonia wastewater.

[0137] Example 2

[0138] This embodiment provides a method for treating phenol and ammonia wastewater, which is the same as the method in Embodiment 1, except that the PVA / PA biological carrier is replaced with a PVA / PA / Fe biological carrier.

[0139] After treatment, the total nitrogen removal rate (TNRE) of the phenol-ammonia wastewater was measured to be 89.9±3.14%, and the COD removal rate (CRE) was 92.9±1.98%. Specific influent and effluent data and treatment effects are as follows: Figure 5 As shown.

[0140] This embodiment also tested the biological carrier and sludge after treating the phenol and ammonia wastewater. It was found that the biological carrier effectively attached microorganisms, with a microbial attachment rate of 6.64 ± 1.01 g VSS / L. At this time, the EPS of the carrier biofilm was measured to be 85.72 ± 3.69 mg g. -1 VSS -1 The initial inoculated sludge EPS was 54.32 ± 3.75 mg g. -1 VSS -1 .

[0141] Based on the biodiversity detection of microorganisms using 16S rRNA, the phyla that accounted for the majority of abundance in the microbial community were Proteobacteria (75%) and Cgloroflexi (9%), totaling 84%. The abundance distribution of typical functional bacterial genera is summarized as follows: Nitrosomonas (belonging to AOB) 4.06%; Nitrospira (belonging to NOB) 0.67%; Candidatus_Brocadia (belonging to AnAOB) 3.19% and Candidatus_Kuenenia (belonging to AnAOB) 0.37%, totaling 3.56%; Thaurea (belonging to DNB) 12.01%, Denitrosoma 1.97%, Limnobacter (belonging to DNB) 0.99%, PHOS-HE36 4.72%, Thermomonas (belonging to DNB) 3.20%, and Ottowia (belonging to DNB) 0.53%, totaling 23.42%. The bacteria (POBs) involved in the degradation of phenol and its intermediate metabolites, organic acids, were: SBR103 (117.03%), WS (68.87%), and A4b (1.62%), totaling 27.52%. Furthermore, the heterotrophic denitrifying bacterium *Ferruginibacter* (0.32%), closely related to iron cycling metabolism, was also identified. *Ferruginibacter* is closely associated with iron metabolism and can degrade iron through Fe... 2+ with Fe 3+ The transformation achieves nitrogen redox, thereby promoting denitrification. The distribution map of microbial diversity in the carrier biofilm is shown below. Figure 6 As shown.

[0142] It is evident that Fe loaded on the biological carrier is beneficial to the growth of bacteria such as Ferruginibacter and promotes denitrification. This embodiment successfully achieved the synergistic symbiosis of POB, AOB, NOB, DNB and AnAOB, effectively treating phenol and ammonia wastewater.

[0143] Comparative Example 1

[0144] This comparative example provides a method for treating phenol and ammonia wastewater. During reactor operation, the reaction time for each cycle is allocated as follows: 10 min for influent, 11-23 h for stirring and aeration, 40 min for settling, and 10 min for effluent discharge. The stirring rate is 20 r / min, the dissolved oxygen (DO) concentration during aeration is controlled at 0-0.3 mg / L, and the water exchange rate during effluent discharge is 1 / 2-2 / 3. The treatment effect is adjusted by controlling the DO concentration. The specific steps are as follows:

[0145] (1) Place 1L of PVA / PA biological carrier (properties of biological carrier are shown in Table 2) and 0.6L of sludge (properties of sludge are shown in Table 1) in the SBR reactor.

[0146] (2) Start the treatment device and directly introduce phenol and ammonia wastewater with a phenol concentration of 230 mg / L and an ammonia concentration of 500 mg / L into the reaction tank through the inlet tank for treatment. During the reaction, aeration and non-aeration are alternated, with aeration and non-aeration time of 5 min each. After 23 h of reaction, let it stand for 40 min, drain water for 10 min, and the water exchange rate is 1 / 2. The water quality is tested. During the reaction, the DO probe is used for real-time monitoring. When the DO reaches the set upper limit of 0.3 mg / L during real-time aeration, the aeration intensity is automatically reduced (the aeration rate is reduced by 5 mL / min).

[0147] It was found that if phenol-ammonia wastewater is treated directly in a stepwise reaction without pretreatment, ammonia-oxidizing bacteria and anaerobic ammonia-oxidizing bacteria will be inhibited by the toxicity of phenols and will not be able to effectively remove ammonia from the wastewater. Furthermore, phenol-oxidizing bacteria and denitrifying bacteria cannot adapt to high concentrations of phenols and will also not be able to effectively remove phenols from the wastewater.

[0148] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0149] The above description is merely a specific embodiment of the present invention, enabling those skilled in the art to understand or implement the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for treating phenol-ammonia wastewater, characterized in that, The processing method includes the following steps: (1) Mix the biological carrier and sludge to obtain a biological carrier-sludge mixture; (2) Pretreatment: Ammonia-containing wastewater containing organic carbon sources is added to the above-mentioned biological carrier-sludge mixture in steps to carry out a stepwise reaction, resulting in a stepwise reaction solution, wherein: The organic carbon source includes non-phenolic organic carbon sources and phenolic organic compounds. In each reaction step, the content of the non-phenolic organic carbon source in the ammonia-containing wastewater remains unchanged or decreases, while the content of the phenolic organic compounds remains unchanged or increases. (3) When the concentration of phenol in the ammonia-containing wastewater added in the stepwise reaction is 90%-100% of the concentration of phenol in the phenol-ammonia wastewater to be treated, the pretreatment is completed; (4) Add phenol and ammonia wastewater for treatment; The sludge includes anaerobic ammonia oxidation sludge, nitrification sludge and denitrification sludge; In both the stepwise reaction described in step (2) and the treatment described in step (4), the concentration of dissolved oxygen must be controlled to be 0-0.3 mg / L. The sludge contains phenol-oxidizing bacteria, ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, anaerobic ammonia-oxidizing bacteria, and denitrifying bacteria; The biological carrier in step (1) is selected from PVA / PA / Fe or PVA / PA porous gel particles.

2. The processing method according to claim 1, characterized in that, The stepwise reaction described in step (2) is carried out in a reaction tank, and the filling volume of the biological carrier is 1 / 4 to 1 / 3 of the effective volume of the reaction tank. And / or, the stepwise reaction in step (2) is carried out in a reaction tank, and the filling volume of the sludge is 1 / 5 to 1 / 4 of the effective volume of the reaction tank; And / or, the reaction time for each step in the stepwise reaction described in step (2) is 11-23 h.

3. The processing method according to claim 1 or 2, characterized in that, Step (2) after obtaining the stepwise reaction solution further includes allowing the stepwise reaction solution to stand and drain.

4. The processing method according to claim 3, characterized in that, After the stepwise reaction solution is allowed to stand, the supernatant is tested. When the total nitrogen removal rate is ≥80% and / or the COD removal rate is ≥80%, in the next reaction step, the content of non-phenolic organic carbon sources in the ammonia-containing wastewater is reduced and the content of phenolic organic matter in the ammonia-containing wastewater is increased.

5. The processing method according to claim 1 or 2, characterized in that, In the stepwise reaction, the organic carbon source in the first step is a non-phenolic organic carbon source, and the COD value of the non-phenolic organic carbon source in the ammonia-containing wastewater is 90%-100% of the COD value of phenol in the phenol-ammonia wastewater to be treated. And / or, in the stepwise reaction, when the content of non-phenolic organic carbon sources in the ammonia-containing wastewater is reduced, the concentration of the non-phenolic organic carbon sources in the ammonia-containing wastewater is reduced by 10-100 g / L compared with the previous step; And / or, in the stepwise reaction, when the content of phenolic organic matter in the ammonia-containing wastewater is increased, the concentration of the phenolic organic matter in the ammonia-containing wastewater increases by 10-100 mg / L compared to the previous step.

6. The processing method according to claim 5, characterized in that, In the stepwise reaction, when the content of non-phenolic organic carbon sources in the ammonia-containing wastewater is reduced, the concentration of the non-phenolic organic carbon sources in the ammonia-containing wastewater is reduced by 50-70 mg / L compared with the previous step. And / or, in the stepwise reaction, when the content of phenolic organic matter in the ammonia-containing wastewater is increased, the concentration of the phenolic organic matter in the ammonia-containing wastewater increases by 10-50 mg / L compared to the previous step.

7. The processing method according to claim 1 or 2, characterized in that, The non-phenolic organic carbon source in step (2) is selected from any one or a combination of at least two of sodium acetate, glucose, or starch; And / or, the phenolic organic compound in step (2) is selected from any one or a combination of at least two of phenol, cresol, aminophenol, nitrophenol, naphthol or chlorophenol.

8. The processing method according to claim 3, characterized in that, The concentration of dissolved oxygen is controlled by aeration, which is performed alternately with non-aeration. And / or, the stepwise reaction described in step (2) is carried out under stirring; And / or, the settling time is 30-50 min; And / or, the water exchange rate during drainage is 1 / 2 to 2 / 3; And / or, the drainage time during drainage is 10-20 minutes.

9. The processing method according to claim 8, characterized in that, Each aeration session lasts 4-6 minutes, and each non-aeration session lasts 5-6 minutes. And / or, the stirring rate of the stirring in step (2) is 10-70 r / min.

10. The processing method according to claim 1 or 2, characterized in that, The processing time described in step (4) is 11-23 hours. And / or, stirring is also required during the processing described in step (4).

11. The processing method according to claim 10, characterized in that, The stirring rate in step (4) is 10-70 r / min.

12. The processing method according to claim 1 or 2, characterized in that, Step (4) further includes settling and effluent disposal of the phenol-ammonia wastewater.

13. The processing method according to claim 12, characterized in that, The settling time is 30-50 minutes.

14. The processing method according to claim 12, characterized in that, The water exchange rate at the outlet is 1 / 2 to 2 / 3.

15. The processing method according to claim 12, characterized in that, The water discharge time is 10-20 minutes.

16. The processing method according to claim 1 or 2, characterized in that, In step (4), the concentration of phenol in the phenol-ammonia wastewater is 0-500 mg / L and the concentration of ammonia is 0-500 mg / L.

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