CN100406398C - Sequencing Batch Airlift Circulation Wastewater Biological Treatment Process - Google Patents

Abstract

The efficient sequencing batch type air lifting circular flow waste water treating bioreactor in alternative anoxia-anaerobic-aerobic process includes one squared or cylindrical reactor unit, one water inlet unit and one water outlet unit as well as one aerating system. The reactor unit includes one reactor body, one triphase separator, conic bottom, air lifting circular flow guide tube and upper deflecting baffle. The present invention also discloses corresponding technological process. By means of the sequencing batch type air lifting circular flow waste water treating bioreactor and the corresponding technological process, double target of oxidizing non-degradable organic pollutant and biological denitrification may be reached in the same reactor, the treated high concentration non-degradable nitrogenous industrial organic waste water may reach the drainage standard, and the residual sludge amount may be reduced by over 80%.

Description

Sequencing Batch Airlift Circulation Wastewater Biological Treatment Process

technical field

The invention belongs to the technical field of water pollution control application, and relates to a biological treatment process and a reactor device for industrial organic waste water containing high-concentration refractory organic pollutants and high-concentration ammonia nitrogen.

Background technique

A large amount of high-concentration toxic/refractory organic nitrogen-containing industrial wastewater is discharged during industrial production, such as yeast wastewater, monosodium glutamate waste liquid, coking wastewater, soy sauce wastewater, landfill leachate, etc., and its water quality is characterized by high concentrations of toxic and refractory organic pollutants and high concentrations of ammonia nitrogen. The combined process of anaerobic/aerobic and nitrification/denitrification is commonly used in the treatment of this kind of wastewater, such as A ² /O, AB method, SBR process, etc. These processes are the traditional activated sludge process and its improved process based on the suspended growth of microorganisms, which have poor adaptability to water quality containing refractory organic pollutants and low degradation efficiency. The denitrification efficiencies of A ² /O and AB processes are generally between 30% and 40%, which cannot meet the treatment requirements. The SBR process is a sequential batch batch activated sludge process with high nitrogen removal efficiency, but its removal effect on refractory organic pollutants is poor. In addition, the above-mentioned process has problems such as long process route, high wastewater reflux ratio, low mixing effect and mass transfer efficiency of unit structures or reactors, sludge reflux and large surplus sludge production, etc., which make the unit structure (reactor) relatively high The concentration of toxic/refractory organic matter has poor adaptability, low processing load, and high infrastructure investment and operating costs.

Domestic and foreign research and industrialization practices have shown that the biofilm process has unique advantages in the treatment of high-concentration toxic/refractory wastewater. The use of unit structures (reactors) is known for airlift bioreactors and biological fluidized bed reactors. Safferman, a scholar at Dayton University in the United States, and Professor Bishop of Cincinnati University (Safferman SI, BishopP.L.Journal of hazardous materials, 1997, 54(3): 241-253) believe that the use of airlift bioreactor or biofluidized bed reaction The process of the device can not only maximize the organic pollutant removal capacity of refractory wastewater but also minimize the sludge production. Therefore, the biofilm process (such as the biological fluidized bed process) presents a good application prospect in the treatment of refractory wastewater. However, the denitrification efficiency of this type of process is similar to that of the aforementioned activated sludge process, which is maintained between 30% and 40%. It needs to be used in conjunction with the nitrification/denitrification process to make wastewater containing high concentrations of organic pollutants and high concentrations of ammonia nitrogen Discharge.

It can be seen that in view of the water quality characteristics of industrial organic wastewater containing high concentrations of refractory organic pollutants and ammonia nitrogen, an efficient wastewater treatment process and reactor that can achieve the dual goals of degradation of refractory organic matter and biological denitrification in the same reactor should be developed It will have a good application prospect.

Contents of the invention

The invention aims at the problems of poor adaptability and low degradation efficiency of traditional activated sludge wastewater biological treatment process and reactor to high-concentration refractory organic pollutants and poor denitrification performance of biofilm reactor (such as biological fluidized bed), etc. , proposed a new type of high-efficiency air-lift internal circulation wastewater treatment bioreactor and process that uses anoxic-anaerobic-aerobic alternately to realize the dual oxidation of refractory organic pollutants and biological denitrification in the same reactor The goal is to make high-concentration refractory nitrogen-containing industrial organic wastewater be discharged up to standard after treatment, and at the same time achieve a reduction of excess sludge of more than 80% (compared to traditional activated sludge processes).

A kind of sequence batch type air-lift circulation wastewater biological treatment process of the present invention adopts the sequence batch type air-lift circulation wastewater biological treatment reactor with the following structure, and carries out according to the following steps:

The structure of the sequencing batch type air-lift circulation wastewater biological treatment reactor includes a square or cylindrical reactor device, water inlet device and water outlet device, wherein the reactor device includes a reactor main body, and the top of the reactor main body is connected with three A phase separator with a conical bottom connected to the bottom, an airlift circulation guide tube is installed in the reactor main body, and an upper flow baffle is fixed above the airlift circulation guide tube, and the reactor device also includes an aeration system;

Its process steps include:

1) Water inlet stage: the raw water is pumped into the reactor from the water inlet tank through the water inlet metering pump, and the water inlet is stopped at the predetermined time, and enters the reaction stage;

2) Reaction stage: It is carried out in the reactor in the form of air-lift circulation, and the switching time of the low-pressure aeration pump is alternately controlled by adjusting the time program of the program controller to control the amount of air introduced into the reactor, thereby alternately performing deficiencies. Oxygen-anaerobic-aerobic biochemical reaction process, until the refractory organic pollutants and ammonia nitrogen in the influent are efficiently degraded or even completely mineralized at this stage, and the reaction stops at the predetermined time and enters the static stage;

3) Standing stage: the mud-water mixture in the reactor is settled by gravity and separated in the three-phase separator, wherein the sludge enters the bottom of the cone through the sludge slide hole, and the supernatant is to be discharged;

4) Drainage stage: the supernatant liquid after static settlement and separation is discharged from the corresponding discharge port into the clear water tank under the condition of the set drainage ratio;

5) Idle stage: After the supernatant is discharged, the reactor enters the idle stage, that is, the state of waiting for water.

The three-phase separator of the present invention is an enlarged structure, which is connected to the reactor main body at 1/2 of the height of the reactor main body, and a row of sludge sliding holes is opened at the bottom of the three-phase separator where the reactor main body is connected.

The upper flow baffle is an inverted trumpet-shaped square or circular structure, and is fixed above the airlift circulation guide tube with three support points.

The water inlet device includes a water inlet metering pump and a water inlet tank, which are installed at the connection between the bottom of the cone and the main body of the reactor; the air supply of the reactor adopts an aeration system, including a low-pressure aeration pump and an aeration device, which is installed at the bottom of the reactor; Both the low-pressure aeration pump and the water inlet metering pump are connected to the program controller, and the water inlet and operation status of the reactor are controlled through the time program setting.

The water outlet device includes a water outlet weir groove, four water outlets and a clean water tank, and the four water outlets are located at different heights of the three-phase separator.

The reactor adopts biological ceramsite or modified sawdust filler carrier, and the microorganisms in the reactor system grow in a mixed growth mode combining suspension growth and attachment growth.

The anoxic-anaerobic-aerobic sequence batch type alternate operation program described in the present invention can be set accordingly according to the water quality index of the influent water and the change status of the water quality index during operation. The specific method is to change the time setting of the program controller to change The cycle of anoxic, anaerobic and aerobic biochemical reactions in the reactor.

The present invention also relates to a sequence batch type airlift circulation wastewater biological treatment process, which adopts two or more sequence batch type airlift circulation wastewater biological treatment reactor structures described in the present invention to be connected in parallel, and each reactor takes turns according to The steps listed in the aforementioned sequential batch type air-lift circulation wastewater biological treatment process of the present invention operate.

The principle of the sequence batch type airlift circulation wastewater biological treatment process applied to the above reactor is:

(1) Biodegradation of refractory organic matter: Airlift circulation bioreactor wastewater treatment process is a kind of bioaugmentation technology (Bioaugumentation), which has both attachment growth method and suspension method growth characteristics, and is a typical composite system. During the start-up and domestication process of anoxic-anaerobic-aerobic alternating operation, the microbial population in the reactor undergoes complex ecological succession, producing characteristic enzymes and high-efficiency dominant strains adapted to refractory substrates. The theoretical basis is The classic theory of microbial enzymology-induction-fit theory. The fluidized operation mode of the reactor creates good mixing and mass transfer conditions between the refractory substrate and microorganisms, and the transfer rate of both oxygen and substrate is significantly higher than that of fixed bed and activated sludge systems. The mixing time is between 15-30s, and the oxygen transfer coefficient (K _La ) is between 18-25h ^-1 . Compared with the traditional activated sludge treatment system, the oxygen transfer efficiency is 20%-30% higher. Due to the design of the high-efficiency three-phase separator and the use of new biological fillers, the biological concentration in the system reaches 10-20g/L, which is 4-5 times that of the traditional activated sludge process, and greatly improves the refractory organic pollutants and microbial film. between the contact reaction interface and the reaction rate. Therefore, the process exhibits excellent performance in the treatment of high-concentration toxic/refractory organic wastewater.

(2) Biological denitrification: Biological denitrification is mainly accomplished through two processes of nitrification and denitrification. Nitrifying bacteria are a kind of chemoautotrophic bacteria, including two physiological flora of nitrosifying bacteria and nitrifying bacteria. wait. The denitrifying bacteria are mostly facultative heterotrophic bacteria, and their growth rate is much higher than that of nitrifying bacteria. In the biological nitrogen removal process, the nitrification process is a limiting step, and the stability of nitrification and the improvement of nitrification speed are the key factors affecting the nitrogen removal efficiency of the whole system. Studies have shown that the nitrification rate of sewage is positively correlated with the concentration of nitrifying bacteria. Therefore, increasing the concentration of nitrifying bacteria has a direct effect on the improvement of biological nitrogen removal efficiency. In the suspension growth system, it is difficult to obtain and maintain a sufficient concentration of nitrifying bacteria, while in the attached growth system, the nitrifying bacteria grow on the surface of the carrier in an immobilized manner, and are not easy to be washed out of the system, so the biomass concentration can be greatly increased . Due to the high-efficiency separation of the three-phase separator, the novel high-efficiency reactor of the present invention enables most of the long-generation nitrifying bacteria that are difficult to survive in the traditional wastewater biological treatment system to be kept in the reactor system, greatly improving the efficiency of biological nitrification. After the wastewater enters the reactor, as the biochemical reaction proceeds, the COD _Cr and COD _Cr /NH ₄ ⁺ -N decrease continuously, which provides good conditions for the growth of autotrophic microorganisms and biological nitrification in the system, so that the NH ₄ in the wastewater ⁺ -N is almost completely transformed into NO ₂ ^- -N and NO ₃ ^- -N. As the operation program enters the anoxic stage, the remaining organic matter in the system acts as an electron donor, and the NO ₂ ^- -N and NO ₃ ^- -N produced during the nitrification process act as electron acceptors to realize the biochemical reaction dominated by the denitrification process. The control of process conditions prevents the denitrification process from producing N ₂ O, a strong greenhouse effect gas, and the final product of denitrification is discharged in the form of N ₂ , effectively realizing biological denitrification.

(3) Reduction of excess sludge: In the process of biological wastewater treatment, excess sludge is mainly produced in the aerobic stage. Because the reactor of the present invention adopts a high-efficiency three-phase separator, the remaining sludge produced in the aerobic stage still stays in the reactor system after being well separated in the three-phase separator, wherein the biomass with strong activity is The form of biofilm attaches to the carrier to continue biodegradation, while the biomass with low activity falls off from the surface of the carrier under the unique hydraulic conditions of the airlift reactor and exists in the reactor in a suspended state. As the operation of the reactor enters the anoxic-anaerobic stage, the suspended microbial cells gradually age and autolyze, and under anaerobic conditions, the bacterial cells are largely digested. The digested product will be mineralized through the sequencing batch operation of the reactor, so as to realize the reduction of excess sludge.

The sequencing batch air-lift circulation wastewater biological treatment process designed according to the above principles, treats industrial organic wastewater containing high concentrations of refractory organic pollutants and high ammonia nitrogen in an anoxic-anaerobic-aerobic alternate manner. Intermittent operation allows the wastewater to experience two processes of biological oxidation of organic matter and biological nitrification-denitrification biological denitrification in the reaction device, and realizes the functions of organic matter oxidation and biological denitrification in the same reactor.

The present invention realizes the purpose of the invention through the above-mentioned reactor and technique, and compared with the prior art, has the following advantages:

(1) Sequencing batch airlift circulation wastewater biological treatment reactor has good mixing effect and high mass transfer efficiency. The mixing time is between 15-30s, and the oxygen transfer coefficient K _La is between 18-25h ^-1 . Compared with the traditional activated sludge treatment system, the oxygen transfer efficiency is 20%-30% higher.

(2) The reactor operates in the state of anoxic-anaerobic-aerobic alternately. The microbial flora in the system presents a very rich population structure through complex ecological succession. High-concentration nitrogen-containing organic industrial wastewater in this processed efficiently in the system.

(3) The reactor has a new structure three-phase separator with good performance, which prolongs the residence time of biomass in the reactor to 30-40 days, and the microorganisms in the reactor system grow in a mixed growth mode combining suspension growth and attachment growth, The biological concentration in the reaction system can reach 10-20g/L, which is 4-5 times that of the traditional activated sludge system. It realizes the operation of the reactor at high biological concentration and improves the biodegradation efficiency of refractory organic pollutants.

(4) Compared with the Sequencing Batch Activated Sludge Process (SBR) process, since the present invention adopts a three-phase separator with good performance, the sludge-water-gas three-phase separation effect is greatly enhanced, and there is no need to set a decanter And the secondary sedimentation tank, the reactor effluent is clear, and the effluent SS is lower than 10mg/L.

(5) Anoxic-anaerobic-aerobic sequential batch operation program can be based on influent water quality indicators (such as COD _Cr , BOD ₅ , BOD ₅ /COD _Cr , COD _Cr /H ₄ ⁺ -N and other parameters) and operation According to the changes of water quality indicators during the period, corresponding settings are made, and the process control method is flexible. The process optimization control program is adopted to reduce a large amount of excess sludge in the anaerobic stage, achieving the effect of reducing excess sludge by more than 80%.

(6) The process involved in the present invention is operated intermittently through sequential batch operation, so that the waste water experiences two processes of biodegradation of organic matter and biological nitrification-denitrification biological denitrification in the reaction device, and realizes organic matter degradation and denitrification in the same reactor. Dual goals of biological denitrification.

Description of drawings

Fig. 1 is the schematic diagram of sequence batch type air-lift circulation wastewater biological treatment reactor device;

Fig. 2 is a schematic diagram of a continuous water inflow treatment process with multiple reactors.

In the figure: 1 low-pressure aeration pump; 2 program controller; 3 water inlet metering pump; 4 water inlet tank; 5 sludge slide hole; 6 three-phase separator; Upstream baffle; 10 diversion baffle in main reaction zone; 11 water outlet one; 12 water outlet two; 13 water outlet three; 14 water outlet four; 15 clear water tank; 16 reactor main body; 19. The mud discharge pipe; 20. The aeration device; 21. Solenoid valve.

Detailed ways

The sequencing batch type airlift circulation wastewater biological treatment reactor and process disclosed in the present invention will be described in detail below in conjunction with the accompanying drawings and examples.

Embodiment one

The target wastewater of the reaction device and wastewater treatment process of the present invention is industrial organic wastewater containing high concentration/refractory organic pollutants and high ammonia nitrogen, such as landfill leachate, yeast wastewater, coking wastewater, monosodium glutamate wastewater, etc. The range of wastewater quality characteristics that the reactor can adapt to is: COD _Cr : ≤1500mg/L, NH ₄ ⁺ -N: ≤300mg/L. Wastewater with a concentration higher than this limit can also achieve good treatment effects when entering the reactor with an appropriate drainage ratio (that is, controlling the influent dilution ratio).

The technical scheme adopted in the present invention is: adopt a circular structure, air-lift type internal circulation bioreactor device containing new internal components, and its height-to-diameter ratio is 3-6:1, as shown in Fig. 1 .

The structure of the novel bioreactor is as follows: a three-phase separator 6 is connected above the main body 16 of the reactor, and a cone bottom 17 is connected below; On the bottom of the cone 17; the upper flow deflector baffle 9 is fixed on the upper plane of the air-lift circulation guide tube 7 with three supporting points.

The new internal components refer to the high-efficiency three-phase separator 6 and the upstream baffle 9 . The three-phase separator 6 is an enlarged structure, which is connected to it at 1/2 of the height of the reactor main body 16, and a row of sludge sliding holes 5 is opened at the bottom of the three-phase separator 6 connected to the reactor main body 16, so that the separated Sludge and biological particles slide down to the main reaction area of the reactor, prolonging the residence time of biomass in the reactor to 30-40 days, and the biological concentration in the reaction system is 4-5 times that of the traditional activated sludge system. In addition, the sludge sliding hole 5 is to open several small holes at the junction of the three-phase separator 6 and the lower plane of the diversion baffle plate 10 in the main reaction zone. Taking the 10L reactor adopted in this embodiment as an example, the size of the holes is The arc length is 40mm x height 15mm, and the opening ratio is 70-80%, so that the sludge after three-phase separation can slide smoothly from this hole into the main reaction zone of the reactor. In addition, a sludge discharge pipe 19 is provided at the bottom of the cone bottom 17. If the amount of sludge in the reactor is too large, a small amount of sludge can be discharged through the sludge discharge pipe 19 on a regular basis. The design of the three-phase separator can also prevent nitrifying bacteria with a long generation time from washing out of the reactor system, and effectively improve the nitrification performance of the reactor.

Open four water outlets at different heights of the three-phase separator: outlet one 11 (located at the exit of weir groove 8), outlet two 12, outlet three 13 and outlet four 14 for setting different drainage ratios It is required for drainage; there is also a clear water tank 15 for collecting the resulting clear water; the reactor is provided with an outlet weir groove 8, which is installed on the top of the three-phase separator 6, and has an overflow function, so that the reactor can be used when the weir is full. Overflow does not lose biomass.

The upper flow baffle 9 is an inverted trumpet-shaped square or circular structure, located at 30-40mm on the upper plane of the inner guide tube, fixed on the upper plane of the guide tube with three support points, the setting of the upper flow baffle 9 can be Change the flow state in the upper part of the reactor, reduce the disturbance of the gas-liquid circulation to the three-phase separation zone, and ensure the high efficiency of the three-phase separation.

The water inlet device of the reactor includes a water inlet metering pump 3 and a water inlet tank 4, which are installed at the connection between the cone bottom 17 and the reactor main body 16; the air supply of the reactor adopts an aeration system, including a low-pressure aeration pump 1 and an aeration device 20. The aeration device 20 adopts a titanium alloy microporous sieve plate aerator, which is installed at the bottom of the reactor; the low-pressure aeration pump 1 and the water inlet metering pump 3 are connected to the program controller 2, and the reaction is controlled by setting the time program Water intake and operating status of the device.

The reactor adopts biological ceramsite or modified sawdust filler and other carriers, so that the microorganisms in the system can grow in a mixed growth mode of suspension growth and attachment growth, and the biological concentration in the reaction system can reach 10-20g/L.

The present invention also relates to a sequence batch type air-lift circulation wastewater biological treatment process, which is carried out by using the above-mentioned sequence batch type air-lift circulation wastewater biological treatment reactor according to the following steps:

1) Water intake stage: the raw water is pumped into the reactor from the water intake tank 4 through the water intake metering pump 3, and the water intake is stopped at a predetermined time, entering the reaction stage.

2) Reaction stage: under the action of airlift circulation, the feed water is quickly mixed with the wastewater and sludge in the reactor, and continuously circulates in the main reaction area of the reactor. By adjusting the time program of the program controller 2 to control the switch of the low-pressure aeration pump 1 to control the amount of air introduced into the reactor, so as to realize the anoxic-anaerobic-aerobic biochemical reaction process in the reaction stage. The time program of each stage of anoxic-anaerobic-aerobic operation of the reactor can be adjusted according to the influent water quality index of the reactor, so as to realize the sequential batch operation mode of the reactor; Various biological redox reactions, such as biodegradation of organic pollutants, nitrification of ammonia nitrogen/denitrification of nitrification products, etc., until the refractory organic pollutants and ammonia nitrogen in the influent are efficiently degraded or even completely mineralized at this stage, until The predetermined time stops the reaction and enters the static stage.

3) Standing stage: the mud-water mixture in the reactor is settled by gravity, and is well separated in the separation zone, wherein the sludge enters the bottom of the reactor through the sludge sliding hole 5, and the supernatant is to be discharged; such as the sludge in the system If the amount is too much, a small amount of excess sludge can be discharged from the sludge discharge pipe 19 at the bottom of the reactor regularly.

4) Drainage stage: the supernatant after standing still and settling and separated is discharged from the corresponding outlet to the clear water tank 15 under the condition of the set drainage ratio. If the drainage ratio is set to 0.5, select the water outlet 4 14 for drainage .

5) Idle stage: After the supernatant is discharged, the reactor enters the idle stage, that is, the state of waiting for water.

Due to the addition of biological ceramsite or modified sawdust filler in the reactor, in the airlift internal circulation reaction system, the carrier is suspended in water under suitable hydraulic conditions, and a dense biofilm will be formed on the surface of the filler and inside the pores. The reactor system is a typical composite reaction system combining activated sludge and biofilm method.

In addition, the anoxic-anaerobic-aerobic sequential batch operation program can be based on influent water quality indicators (such as COD _Cr , BOD ₅ , BOD ₅ /COD _Cr , COD _Cr /NH ₄ ⁺ -N and other parameters) and during operation The specific method is to change the time setting of the program controller to change the cycle of anoxic, anaerobic, and aerobic biochemical reactions in the reactor or to increase the cycle times of the anoxic-anaerobic-aerobic cycle .

Wastewater undergoes two types of biochemical reactions: degradation of organic matter and biological nitrification-denitrification biological denitrification in the reaction device, including the following specific processes and characteristics:

(1) The wastewater to be treated is pumped into the new bioreactor, and the degradation of organic matter mainly occurs in the first 1 to 2 cycles of the anoxic-anaerobic-aerobic sequential batch cycle.

(2) As the biochemical reaction proceeds, COD _Cr and COD _Cr /H ₄ ⁺ -N decrease continuously, which provides good conditions for the growth of autotrophic microorganisms and biological nitrification in the system, making NH ₄ ⁺ -N in wastewater It is transformed into NO ₂ ^- -N and NO ₃ ^- -N, basically no organic matter is consumed at this stage, which is the reaction process dominated by nitrification.

(3) As the operation program enters the anoxic stage, the remaining organic matter in the system acts as the electron donor, and the NO ₂ ^- -N and NO ₃ ^- -N produced during the nitrification process act as the electron acceptor, realizing the denitrification process-based biochemical reaction.

(4) After the wastewater undergoes the set anoxic-anaerobic-aerobic alternating operation process, the refractory organic matter and NH ₄ ⁺ -N in the influent are efficiently biodegraded, and the final products of biological oxidation are CO ₂ and H ₂ O and N ₂ , to achieve the standard discharge of wastewater.

In the laboratory, a kind of typical high-concentration refractory nitrogen-containing organic wastewater—garbage leachate was treated by adopting the sequencing batch type air-lift circulation wastewater biological treatment reactor (total volume is 10L) and process introduced in this embodiment. The wastewater quality indicators are: COD _Cr 2800mg/L; NH ₄ ⁺ -N 530mg/L; SS 280mg/L; pH 7.9. At this time, the influent C/N ratio is 5.3, and the time program is set as: influent (0.5h)-anoxic (1h)-anaerobic (2h)-aerobic (4h)-drainage (0.5h). The biodegradability of the water makes appropriate adjustments to the run program settings. If the C/N is reduced and the biodegradability of the influent becomes poor, it may be considered to extend the cycle period or increase the cycle times of the anoxic-anaerobic-aerobic process, and set the program to continuously cycle anoxic-anaerobic-aerobic , until the effluent is discharged up to the standard before entering the next cycle. In this example, the drainage ratio is set at 0.5. After testing, the raw water is pumped into the reactor, and the water quality indicators of the mixed solution formed with the remaining muddy water are: COD _Cr = 1200 ~ 1500 mg/L, NH ₄ ⁺ -N = 280~300mg/L, SS=80~100mg/L, pH=7.6. Under the above operating procedures, the anoxic-anaerobic-aerobic process cycle is carried out for four cycles. After treatment, the effluent indicators can reach: COD _Cr = 80 ~ 100mg/L, NH ₄ ⁺ -N = 5 ~ 10mg/L, SS=5～10mg/L, pH=6.5～7.2. The removal efficiency of each indicator reaches: COD _Cr ≥ 93%, NH ₄ ⁺ -N ≥ 96%, SS ≥ 90%.

Embodiment two

The present invention is an integrated reactor. In addition to the intermittent operation of a single reactor introduced in Example 1, it can also be a plurality of reactors connected in parallel and continuously fed into water, that is, a sequence of two or more batches. The wastewater biological treatment reaction system composed of airlift circulation wastewater biological treatment reactor is shown in Figure 2.

Embodiment 2 shown in Fig. 2 adopts 4 reactors (I～IV) of the same volume connected in parallel. The structures, processes and principles of the four reactors are the same as those described in Example 1.

During operation, the operating cycle settings of the four reactors are consistent. When reactor I completes the water intake, it enters the reaction period. At this time, II starts to enter the water, and so on. The reaction cycle (water intake-reaction-standstill-drainage) enters the state of idle (waiting for water intake). When the IV finishes the water intake, the I enters a new round of water intake. For any one of the reactors in I～IV, the mode of operation is all the same as the above-mentioned embodiment one. The parallel operation of the four reactors is controlled by a program controller 2 . Therefore, the second embodiment shown in Fig. 2 can realize continuous water feeding and batch reaction.

Claims (8)

1. A sequence batch type air-lift circulation wastewater biological treatment process, is characterized in that, adopts the sequence batch type air-lift circulation wastewater biological treatment reactor of following structure, carries out according to the following steps: The structure of the sequencing batch type air-lift circulation wastewater biological treatment reactor comprises a square or cylindrical reactor device, water inlet device and water outlet device, wherein the reactor device includes a reactor main body (16), and the reactor main body (16) The top is connected with a three-phase separator (6), and the bottom is connected with a cone bottom (17). An air-lift circulation guide tube (7) is installed in the reactor main body (16), and an upper flow baffle (9 ) is fixed above the airlift circulation guide tube (7), and the reactor device also includes an aeration system; Its process steps include: 1) Water inlet stage: the raw water is pumped into the reactor from the water inlet tank (4) through the water inlet metering pump (3), and the water inlet is stopped at a predetermined time, and enters the reaction stage; 2) Reaction stage: in the reactor, it is carried out in the way of airlift circulation, and the time program of the program controller (2) is alternately controlled to control the switching time of the low-pressure aeration pump (1) to control the air flowing into the reactor amount, so that the anoxic-anaerobic-aerobic biochemical reaction process is alternately carried out until the refractory organic pollutants and ammonia nitrogen in the influent are efficiently degraded or even completely mineralized at this stage, and the reaction stops at the predetermined time and enters the static state. stage; 3) Standing stage: the mud-water mixture in the reactor is settled by gravity and separated in the three-phase separator (6), wherein the sludge enters the bottom of the cone (17) through the sludge slip hole (5), and the supernatant is left to emission; 4) Drainage stage: the supernatant liquid after static settlement and separation is discharged from the corresponding discharge port into the clear water tank under the condition of the set drainage ratio; 5) Idle stage: After the supernatant is discharged, the reactor enters the idle stage, that is, the state of waiting for water. 2. The sequence batch type air-lift circulation wastewater biological treatment process according to claim 1, characterized in that the three-phase separator (6) is an enlarged structure, at 1/2 of the height of the reactor main body (16) It is connected with the reactor main body (16), and a row of sludge sliding holes (5) is opened at the bottom of the three-phase separator (6) where it is connected with the reactor main body (16). 3. The sequence batch type air-lift circulation wastewater biological treatment process according to claim 1, characterized in that the upper flow baffle (9) is an inverted trumpet-shaped square or circular structure, fixed with three support points Above the airlift circulation guide tube (7). 4. The sequence batch type airlift circulation wastewater biological treatment process according to claim 1, characterized in that the water inlet device comprises a water inlet metering pump (3) and a water inlet tank (4), installed on the bottom of the cone (17) With the junction of the reactor main body (16); the air supply of the reactor adopts an aeration system, including a low-pressure aeration pump (1) and an aeration device (20), which are installed at the bottom of the reactor; the low-pressure aeration pump (1 ) and the water inlet metering pump (3) are connected with the program controller (2), and the water inlet and the running state of the reactor are controlled through the time program setting. 5. The sequence batch type air-lift circulation wastewater biological treatment process according to claim 1 is characterized in that the water outlet device comprises an outlet weir groove (8), four water outlets (11, 12, 13, 14) and cleaning The water tank (15) and four water outlets (11, 12, 13, 14) are located at different heights of the three-phase separator (6). 6. The sequence batch type air-lift circulation wastewater biological treatment process according to claim 1, characterized in that the reactor adopts biological ceramsite or modified sawdust filler carrier, and the microorganisms in the reactor system are combined with suspension growth and attachment growth Mixed growing methods. 7. The sequence batch type air-lift circulation wastewater biological treatment process according to claim 1, characterized in that: the anoxic-anaerobic-aerobic sequence batch type alternate operation program can be based on the influent water quality index and the water quality index during operation The specific method is to change the time setting of the program controller to change the cycle of anoxic, anaerobic and aerobic biochemical reactions in the reactor. 8. A sequencing batch type airlift circulation wastewater biological treatment process, characterized in that: two or more of the sequence batch type airlift circulation wastewater biological treatment reactor structure described in any one of claims 1 to 6 Connected in parallel, each reactor operates according to the steps described in claim 1 in turn.

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