CN112299655B - A New Treatment Process for Aged Landfill Leachate - Google Patents

Abstract

The invention relates to a new process for treating old landfill leachate, which is characterized by comprising the following steps: (1) preparing a treatment system for old landfill leachate; (2) firstly, the landfill leachate enters the sewage regulation tank through the water inlet pipe, and passes through the A certain amount of NaOH solution dissolved in the first dosing tank is added to the sewage conditioning tank through the first dosing pump, so that the pH value of the landfill leachate in the sewage conditioning tank is maintained between 10.5-11; The landfill leachate is directly sent to the wave tube of the dynamic wave stripping device by the sewage centrifugal pump through the rotor flowmeter for foam stripping. , the sewage is discharged from the drainage pipe; (3) the water blown off by the dynamic wave stripping device enters the adjustment tank, the reaction tank, the coagulation tank, the sedimentation tank, and the A/O type SBR process through the drainage pipeline in turn. The investment cost is low, the secondary pollution is reduced, and the processing and operation cost is greatly reduced.

Description

A New Treatment Process for Aged Landfill Leachate

technical field

The invention relates to a new process for treating aged landfill leachate, and relates to the technical field of landfill leachate treatment.

Background technique

During the process of stacking and landfilling, the garbage undergoes fermentation, rainwater flushing, leaching, surface water and groundwater immersion, etc., which will produce a large amount of landfill leachate, and its ammonia nitrogen concentration will increase year by year with the extension of the landfill age. Landfill leachate can be regarded as a heavily polluted three-phase system. Improper handling will cause serious secondary pollution to surface water, groundwater, soil, and atmosphere, and endanger human health. Therefore, landfill leachate must be effectively treated to minimize its impact on the environment. However, due to the particularity of the water quality of landfill leachate, there are still many technical and economic problems in the treatment of landfill leachate.

For the treatment of high ammonia nitrogen landfill leachate, the enhanced MBR (Membrane Bio-Reactor) process followed by the "NF+RO" advanced treatment process (Nanofiltration+ReverseOsmosis, nanofiltration+reverse osmosis) is widely used in practice. , After this process, the effluent can reach the standard, but a large amount of concentrated liquid will be produced. The concentration of refractory organic pollutants, inorganic salts and metal ions in the concentrated liquid is higher than that of the leachate, and the biodegradability is poor. It will cause more serious secondary pollution to surface water, groundwater, soil environment, etc.; the nanofiltration concentrate is returned to the front-end anaerobic reactor, where the high concentration of salt accumulates repeatedly for many years, a vicious circle, which will gradually make the biochemical reaction The system is paralyzed, eventually rendering the equipment inoperable; the cost of treating landfill leachate with traditional processes is getting higher and higher. Therefore, improving the ammonia nitrogen treatment efficiency in landfill leachate, reducing investment per ton of water, reducing secondary pollution, and prolonging the service life of equipment are the main problems to be solved urgently in the current landfill leachate treatment.

SUMMARY OF THE INVENTION

In view of the deficiencies of the prior art, the technical problem to be solved by the present invention is to provide a new process for treating aged landfill leachate.

In order to solve the above-mentioned technical problems, the technical scheme of the present invention is: a new old landfill leachate treatment process, comprising the following steps:

(1) Prepare an aging landfill leachate treatment system;

(2) First, the landfill leachate enters the sewage regulation tank through the water inlet pipe, and by dissolving a certain amount of NaOH solution in the first dosing tank and adding it to the sewage regulation tank through the first dosing pump, the landfill seepage in the sewage regulation tank is obtained. The pH value of the filtrate is maintained between 10.5-11; the landfill leachate in the sewage conditioning tank is directly sent to the wave tube of the dynamic wave stripping device by the sewage centrifugal pump through the rotameter for foam stripping, and the dynamic wave stripping device is used for foam stripping. The stripped liquid flows into the reaction circulation box, and after several cycles, the sewage is discharged from the drainage pipe;

(3) The water stripped by the dynamic wave stripping device enters the regulating tank, the reaction tank, the coagulation tank and the sedimentation tank in turn through the drainage pipeline. The regulating tank uses diluted H ₂ SO ₄ to adjust the pH of the effluent to 3~4. Add FeSO ₄ ·7H ₂ O to the reaction tank and mix with the raw water, then add H ₂ O ₂ to the coagulation tank to carry out the Fenton reaction, and finally adjust the pH of the water sample to about 8 with NaOH, and let it stand in the sedimentation tank 0.5 h, the supernatant is discharged through the drainage pipe, and the lower sediment is discharged through the sludge discharge valve;

(4) The effluent after the Fenton reaction adopts the instantaneous inlet water to enter the A/O type SBR process, and runs under anoxic conditions for 3 hours with stirring, and the DO concentration in the anoxic section is controlled at 0.2 mg/L, and then runs under aeration conditions for 8 hours. h, the aeration volume in the aerobic aeration section was kept constant, the DO concentration in the aerobic section was 3-4 mg/L, and the effluent was discharged from the reactor after 30 min of precipitation.

Preferably, a dynamic wave stripping device is used to strengthen the pretreatment. Before the treatment, NaOH is added to the first dosing tank to adjust the pH to 10.5, the stripping time is 5 h, the water intake is adjusted to 0.4 m³/h, and the air intake is 155 m³/h, that is, the gas-liquid ratio is 387.5.

Preferably, the Fenton reaction needs to adjust the pH of the sewage to 3~4, which is conducive to the generation of hydroxyl radicals (•OH), adding FeSO ₄ 7H ₂ O and mixing with the raw water, and then adding H ₂ O ₂ , After sufficient reaction, the pH was adjusted to about 8 with NaOH, which was beneficial to the formation of flocculation and precipitation.

Preferably, the A/O-type SBR process has an operation cycle of 12 hours, 2 cycles per day, anoxic stirring time of 3 hours, aeration time of 8 hours, and precipitation time of 30 minutes. Water inflow for the next cycle.

Preferably, the old landfill leachate treatment system includes a sewage water inlet pipe (1), a first dosing tank (2), a first dosing pump (3), a sewage conditioning tank (4), a sewage centrifugal pump (5), Pressure gauge (6), power wave stripping device (7), reaction cycle box (8), power distribution control cabinet (9), partition (10), adjustable speed fan (11), air inlet flowmeter ( 12) Power wave blow-off nozzle (13), wave pipe (14), return pipe (15), drain pipe control valve (16), drain pipe (17), second dosing tank (18), second dosing tank (18), Medicine pump (19), regulating tank (20), reaction tank (22), solid dosing device (23), stirring device (24), third dosing tank (25), third dosing pump (26), Coagulation tank (27), fourth dosing tank (29), fourth dosing pump (30), sedimentation tank (31), water outlet valve (32), sludge discharge valve (33), A/O type SBR reaction device (34), air compressor (35), gas flow meter (36), microporous aeration head (37), DO measuring instrument (39), DO probe (40), pH measuring instrument (41), pH probe (42), vent valve (45).

Preferably, the input end of the water inlet pipe (1) is connected to the landfill leachate in the equalization tank of the landfill, the output end of the water inlet pipe (1) is connected to the top water inlet of the sewage conditioning tank (4), and the NaOH passes through the first addition The medicine tank (2) is mixed with the landfill leachate in the sewage regulating tank (4) through the first dosing pump (3), and the output end of the sewage regulating pool (4) is connected to the sewage centrifugal pump (5), and the landfill leachate is The pressure gauge (6) enters the wave tube (14) of the dynamic wave stripping device (7), and is ejected upward in a radial swirling flow by the dynamic wave stripping nozzle (13) inside the wave tube (14). The speed regulating fan (11) is in countercurrent contact with the high-speed rotating liquid flow inside the wave tube (14) through the air inlet flowmeter (12), and the liquid blown off by the dynamic wave stripping device (7) flows into the reaction circulation box ( 8), the reaction circulation box (8) is vertically provided with a partition (10), and a gap is formed between the top and bottom of the partition (10) and the reaction circulation box (8). After the separator (10) in (8) is hydraulically stirred, a part of the liquid is sent to the dynamic wave stripping device (7) by the sewage centrifugal pump (5) again through the return pipe (15) for cyclic stripping treatment. The dynamic wave stripping device (7) The power distribution control cabinet (9) is installed on it, the drain pipe control valve (16) is opened, and the sewage after blowing off is discharged from the drain pipe (17) to the adjustment tank (20).

Preferably, the sewage after stripping is mixed with the H ₂ SO ₄ added by the second dosing tank ( 18 ) through the second dosing pump ( 19 ) in the adjustment tank ( 20 ), and the adjustment tank ( 20 ) The output end is connected to the reaction tank (22) through a drainage pipe, FeSO ₄ ·7H ₂ O is added into the reaction tank (22) through the solid dosing device (23), and the stirring device (24) on the reaction tank (22) is used to add FeSO ₄ ·7H ₂ O is mixed with sewage, the reaction tank (22) is connected with the coagulation tank (27), and H ₂ O ₂ enters the coagulation through the third dosing tank (25) and the third dosing pump (26). Pool (27), and the sewage with uniform Fe ²⁺ is mixed and reacted with a stirring device in the coagulation tank (27), the coagulation tank (27) is connected with the sedimentation tank (31), and NaOH is added through the fourth dosing tank (27). The tank (29) and the fourth dosing pump (30) enter the sedimentation tank (31) to adjust the pH of the sewage to about 8, so that the sludge settles, and the supernatant enters the A/O type SBR reactor ( 34), the sedimented sludge is discharged through the sludge discharge valve (33).

Preferably, the sewage treated by the Fenton reaction enters the A/O type SBR reactor (34), and is operated under anoxic conditions with stirring by a stirring device for 3 hours. Injection through the microporous aeration head (37), the microporous aeration head (37) is located at the inner bottom of the A/O type SBR reactor (34), and runs for 8h under aeration conditions, DO reacts through the A/O type SBR The DO probe (40) at the top of the reactor (34) is connected to the DO meter (39) for monitoring, and the pH is monitored through the pH probe (42) at the top of the A/O SBR reactor (34), which is connected to the pH meter (41). The treated effluent is discharged through a water outlet valve with a drainage pipe, and a vent valve (45) is provided at the bottom of the A/O type SBR reactor (34) for venting and discharging sludge.

Compared with the prior art, the present invention has the following beneficial effects: the treatment process adopts a novel non-membrane process to treat the landfill leachate, the investment cost is low, the secondary pollution is reduced, and the treatment operation cost is greatly reduced, especially for nitrogen in the landfill leachate. The removal rate of elements and organic matter is high, so that the COD, TN, ammonia nitrogen, etc. in the treated effluent meet the discharge standard of "Pollution Control Standards for Domestic Waste Landfills" (GB16889-2008).

The present invention will be described in further detail below with reference to the accompanying drawings and specific embodiments.

Description of drawings

FIG. 1 is a schematic structural diagram of an embodiment of the present invention.

In the figure: water inlet pipe (1), first dosing tank (2), first dosing pump (3), sewage regulating tank (4), sewage centrifugal pump (5), pressure gauge (6), power wave blowing The stripping device (7), the reaction cycle box (8), the power distribution control cabinet (9), the partition plate (10), the adjustable speed fan (11), the air inlet flowmeter (12), the power wave blowing and stripping nozzle ( 13), wave pipe (14), return pipe (15), drain pipe control valve (16), drain pipe (17), second dosing tank (18), second dosing pump (19), regulating pool ( 20), reaction tank (22), solid dosing device (23), stirring device (24), third dosing tank (25), third dosing pump (26), coagulation tank (27), fourth Dosing tank (29), fourth dosing pump (30), sedimentation tank (31), water outlet valve (32), sludge discharge valve (33), A/O type SBR reactor (34), air compressor ( 35), gas flow meter (36), microporous aeration head (37), DO measuring instrument (39), DO probe (40), pH measuring instrument (41), pH probe (42), vent valve (45) .

Detailed ways

In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, the following specific embodiments are given and the accompanying drawings are described in detail as follows.

As shown in Figure 1, a new old landfill leachate treatment process includes the following steps:

(1) Prepare an aging landfill leachate treatment system;

(2) First, the landfill leachate enters the sewage regulation tank through the water inlet pipe, and by dissolving a certain amount of NaOH solution in the first dosing tank and adding it to the sewage regulation tank through the first dosing pump, the landfill seepage in the sewage regulation tank is obtained. The pH value of the filtrate is maintained between 10.5-11; the landfill leachate in the sewage conditioning tank is directly sent to the wave tube of the dynamic wave stripping device by the sewage centrifugal pump through the rotameter for foam stripping, and the dynamic wave stripping device is used for foam stripping. The stripped liquid flows into the reaction circulation box, and after several cycles, the sewage is discharged from the drainage pipe;

(3) The water stripped by the dynamic wave stripping device enters the regulating tank, the reaction tank, the coagulation tank and the sedimentation tank in turn through the drainage pipeline. The regulating tank uses diluted H ₂ SO ₄ to adjust the pH of the effluent to 3~4. Add FeSO ₄ ·7H ₂ O to the reaction tank and mix with the raw water, then add H ₂ O ₂ to the coagulation tank to carry out the Fenton reaction, and finally adjust the pH of the water sample to about 8 with NaOH, and let it stand in the sedimentation tank 0.5 h, the supernatant is discharged through the drainage pipe, and the lower sediment is discharged through the sludge discharge valve;

(4) The effluent after the Fenton reaction adopts the instantaneous inlet water to enter the A/O type SBR process, and runs under anoxic conditions for 3 hours with stirring, and the DO concentration in the anoxic section is controlled at 0.2 mg/L, and then runs under aeration conditions for 8 hours. h, the aeration volume in the aerobic aeration section was kept constant, the DO concentration in the aerobic section was 3-4 mg/L, and the effluent was discharged from the reactor after 30 min of precipitation.

In the embodiment of the present invention, a dynamic wave stripping device is used to strengthen the pretreatment. Before the treatment, NaOH is added to the first dosing tank to adjust the pH to 10.5, the stripping time is 5 h, and the water intake is adjusted to 0.4 m³/h. The intake air volume is 155 m³/h, that is, the gas-liquid ratio is 387.5.

In the embodiment of the present invention, the pH of the sewage needs to be adjusted to 3~4 for the Fenton reaction, which is conducive to the generation of hydroxyl radicals (•OH), adding FeSO ₄ • 7H ₂ O and mixing with the raw water before adding H ₂ O ₂ . After fully reacting, adjust the pH to about 8 with NaOH, which is conducive to the formation of flocculation and precipitation.

In the embodiment of the present invention, the A/O-type SBR process has an operation cycle of 12 hours, 2 cycles per day, anoxic stirring time of 3 hours, aeration time of 8 hours, precipitation time of 30 minutes, and rest after effluent. After 30 min, proceed to the next cycle of water infusion.

In the embodiment of the present invention, the aging landfill leachate treatment system includes a sewage water inlet pipe (1), a first dosing tank (2), a first dosing pump (3), a sewage conditioning tank (4), and a sewage centrifugal pump (5), pressure gauge (6), power wave stripping device (7), reaction cycle box (8), power distribution control cabinet (9), partition (10), adjustable speed fan (11), inlet Air flow meter (12), dynamic wave blow-off nozzle (13), wave pipe (14), return pipe (15), drain pipe control valve (16), drain pipe (17), second dosing tank (18) , the second dosing pump (19), the regulating pool (20), the reaction pool (22), the solid dosing device (23), the stirring device (24), the third dosing tank (25), the third dosing pump (26), coagulation tank (27), fourth dosing tank (29), fourth dosing pump (30), sedimentation tank (31), water outlet valve (32), sludge discharge valve (33), A/ O-type SBR reactor (34), air compressor (35), gas flow meter (36), microporous aeration head (37), DO measuring instrument (39), DO probe (40), pH measuring instrument (41) ), pH probe (42), vent valve (45).

In the embodiment of the present invention, the input end of the water inlet pipe (1) is connected to the landfill leachate in the equalization tank of the landfill, the output end of the water inlet pipe (1) is connected with the top water inlet of the sewage conditioning tank (4), and the NaOH The first dosing tank (2) is mixed with the landfill leachate through the first dosing pump (3) in the sewage conditioning tank (4), and the output end of the sewage conditioning tank (4) is connected to the sewage centrifugal pump (5). The landfill leachate enters the wave tube (14) of the dynamic wave stripping device (7) through the pressure gauge (6), and is ejected upward in a radial swirling flow by the dynamic wave stripping nozzle (13) inside the wave tube (14). The high-speed airflow is in countercurrent contact with the high-speed rotating liquid flow inside the wave tube (14) by the adjustable-speed fan (11) through the air inlet flowmeter (12), and the liquid blown off by the dynamic wave stripping device (7) flows into the reaction In the circulation box (8), the reaction circulation box (8) is vertically provided with a partition plate (10), and a gap is provided between the top and bottom of the partition plate (10) and the reaction circulation box (8). After the separator (10) in the reaction circulation box (8) is hydraulically stirred, a part of the liquid is sent to the power wave stripping device (7) by the sewage centrifugal pump (5) through the return pipe (15) again for cyclic stripping treatment. A power distribution control cabinet (9) is installed on the wave stripping device (7), the drain pipe control valve (16) is opened, and the sewage after stripping is discharged from the drain pipe (17) to the regulating tank (20).

In the embodiment of the present invention, the sewage after stripping is mixed with the H ₂ SO ₄ added by the second dosing tank ( 18 ) through the second dosing pump ( 19 ) in the adjustment tank ( 20 ), and the adjusted The output end of the tank (20) is connected to the reaction tank (22) through a drainage pipe, and FeSO ₄ ·7H ₂ O is fed into the reaction tank (22) through the solid dosing device (23), and the stirring device on the reaction tank (22) is used. (24) Mix FeSO ₄ ·7H ₂ O with sewage, the reaction tank (22) is connected with the coagulation tank (27), and the H ₂ O ₂ passes through the third dosing tank (25) and the third dosing pump (26). ) into the coagulation tank (27), and the sewage with uniform Fe ²⁺ reacts with a stirring device in the coagulation tank (27), the coagulation tank (27) is connected with the sedimentation tank (31), and the NaOH passes through The fourth dosing tank (29) and the fourth dosing pump (30) enter the sedimentation tank (31) to adjust the pH of the sewage to about 8, so that the sludge settles, and the supernatant enters the A/O type through the outlet valve (32). In the SBR reactor (34), the sedimented sludge is discharged through the sludge discharge valve (33).

In the embodiment of the present invention, the sewage treated by the Fenton reaction enters the A/O type SBR reactor (34), and is operated under anoxic conditions with stirring by a stirring device for 3 hours. The meter (36) is ejected through the microporous aeration head (37), and the microporous aeration head (37) is located at the inner bottom of the A/O type SBR reactor (34). The DO probe (40) at the top of the O-type SBR reactor (34) is connected to the DO meter (39) for monitoring, and the pH is connected to the pH meter ( 41) Monitoring, the treated effluent is discharged through the water outlet valve with a drainage pipe, and a vent valve (45) is provided at the bottom of the A/O SBR reactor (34) for venting and sludge discharge.

The principle of the present invention is as follows (the process of using dynamic wave stripping to strengthen pretreatment and biological treatment to treat landfill leachate):

(1) The high-speed rotating liquid flow in the middle and lower part of the dynamic wave stripping device is in countercurrent contact with the high-speed air flow from the top of the wave tube. When the gas-liquid two phases reach momentum balance, the high-speed rotating liquid phase jet will be involved in a large amount of gas phase. With the continuous increase and outward expansion of the pressurized gas wrapped and separated by the phase, a large number _of bubbles are formed in the gas phase that is continuously _wrapped and separated by the liquid phase. The form of ₂ dissociates, and resolves into the gas phase through the huge gas-liquid interface formed by the foam, and then leaves the system with a large amount of airflow entering the dynamic wave device to complete the separation of ammonia and nitrogen.

(2) The oxidizing substance in the Fenton reagent is the reaction generated •OH, which is generated by the decomposition of H ₂ O ₂ catalyzed by Fe ²⁺ . The detailed process will occur as follows:

Fe ²⁺ + H ₂ O ₂ → Fe ³⁺ + OH ^- + •OH

RH + •OH → R• + H ₂ O

R + Fe ³⁺ → R ⁺ + Fe ²⁺

Fe ²⁺ + •OH → Fe ³⁺ + OH ^-

When low pH is favorable for the formation of •OH. Fe ²⁺ in the Fenton reagent is oxidized to Fe ³⁺ in the reaction, and then Fe ^{3 +} reacts with OH ^- at high pH, which is conducive to the formation of flocculent precipitates, and some organic matter in the wastewater enters the flocculation precipitate and is removed .

(3) SBR is the abbreviation of Sequencing Batch Activated Sludge Process, which is an activated sludge sewage treatment technology operated by intermittent aeration. When the reactor is started, the activated sludge contains a large number of heterotrophic bacteria (denitrifying bacteria), and the content of nitrifying bacteria in the sludge is very small, so the sludge needs to be domesticated. The nitrifying bacteria dominate and achieve the purpose of domestication. A/O type SBR process adjusts the time and sequence of anaerobic stirring and aerobic aeration in the reactor, so that the reaction environment in the tank is always in an anaerobic-aerobic alternating state. Ammonia nitrogen is oxidized into NO ₂ ^- -N and NO ₃ ^- -N, and in anaerobic state, through the action of denitrifying bacteria, NO ₂ ^- -N and NO ₃ ^- -N are reduced to N ₂ to realize the pollution of pollutants. remove.

The beneficial effects of the present invention are:

1. The present invention uses the combination of dynamic wave stripping strengthening pretreatment + Fenton oxidation + A/O type SBR biological treatment, and the separation efficiency of ammonia nitrogen can reach more than 90% through the pretreatment of dynamic wave stripping; Fenton's reagent is used for strong oxidation, which has a better effect on COD removal, and the B/C value is increased from 0.16 to more than 0.47. A/O type SBR process can not only reduce the ammonia nitrogen value of leachate, but also through the anaerobic stirring stage of denitrification. process to remove pollutants.

2. Compared with the existing landfill leachate treatment process (enhanced MBR process followed by "NF+RO" advanced treatment process), the present invention adopts a new non-membrane process to treat landfill leachate, reduces investment costs, and solves membrane concentration from the source. The problem of liquid is reduced, secondary pollution is reduced, the system integration is less affected by limiting factors such as external temperature, and the processing and operation cost is greatly reduced.

3. The treatment process of the present invention has low cost, good treatment effect and less secondary pollution, especially high removal rate of nitrogen and organic matter in landfill leachate, so that COD, TN, ammonia nitrogen, etc. Landfill Pollution Control Standard (GB16889-2008) emission standard.

4. The treatment cost per ton of water (pharmaceuticals, labor, water and electricity) for the treatment of high ammonia nitrogen landfill leachate in the present invention is 46 yuan, the investment cost per ton of water will be saved by more than 20% compared with the traditional landfill leachate treatment process, and the operating cost per ton of water will be reduced More than 15%, the annual saving of operating costs reaches more than 132 million yuan, and it has a good application prospect for the design and transformation of aging landfills.

Application Example 1:

Fuzhou Hongmiaoling Waste Comprehensive Treatment Plant Leachate Treatment Plant equalization tank has a TN content of about 1200 mg/L, an ammonia nitrogen content of about 950 mg/L, and a COD content of about 3500 mg/L; Treatment, before the pretreatment process, add NaOH to the first dosing tank (2) to adjust the pH to 10.5, the stripping time is 5h, the water intake is adjusted to 0.4 m³/h, and the air intake is 155 m³/h, that is, the gas The liquid ratio is 387.5, the effluent after the dynamic wave stripping treatment enters the adjustment tank (20), the pH of the leachate is adjusted to 3~4 with diluted H ₂ SO ₄ , and FeSO ₄ ·7H ₂ O is first added to the reaction tank (22 ), then add H ₂ O ₂ in the coagulation tank (27) to react for 20~30 min, adjust the pH of the water sample to about 8 with NaOH in the sedimentation tank (31), let it stand for 0.5 h, and the supernatant liquid enters A/ The O-type SBR reactor (34) was operated under anoxic stirring for 3 h, under aerobic aeration for 8 h, and the precipitation time was 30 min.

The effluent quality after the above process treatment: COD is 90 mg/L, TN is 35 mg/L, and ammonia nitrogen is 20 mg/L, which meets the requirements of TN <40 in the Pollution Control Standard for Domestic Waste Landfills (GB16889-2008). mg/L, ammonia nitrogen <25 mg/L, COD <100 mg/L.

The present invention is not limited to the above-mentioned best embodiment, and anyone can come up with other various forms of new old landfill leachate treatment processes under the inspiration of the present invention. All equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

Claims (1)

1. a new old-age landfill leachate treatment process, is characterized in that: comprise the following steps: (1) Prepare an aging landfill leachate treatment system; (2) First, the landfill leachate enters the sewage regulation tank through the water inlet pipe, and by dissolving a certain amount of NaOH solution in the first dosing tank and adding it to the sewage regulation tank through the first dosing pump, the landfill seepage in the sewage regulation tank is obtained. The pH value of the filtrate is maintained between 10.5-11; the landfill leachate in the sewage conditioning tank is directly sent to the wave tube of the dynamic wave stripping device by the sewage centrifugal pump through the rotameter for foam stripping, and the dynamic wave stripping device is used for foam stripping. The stripped liquid flows into the reaction circulation box, and after several cycles, the sewage is discharged from the drainage pipe; (3) The water stripped by the dynamic wave stripping device enters the regulating tank, the reaction tank, the coagulation tank and the sedimentation tank in turn through the drainage pipeline. The regulating tank uses diluted H ₂ SO ₄ to adjust the pH of the effluent to 3~4. Add FeSO ₄ ·7H ₂ O to the reaction tank and mix with the raw water, then add H ₂ O ₂ to the coagulation tank to carry out the Fenton reaction, and finally adjust the pH of the water sample to about 8 with NaOH, and let it stand in the sedimentation tank 0.5 h, the supernatant is discharged through the drainage pipe, and the lower sediment is discharged through the sludge discharge valve; (4) The effluent after the Fenton reaction adopts the instantaneous inlet water to enter the A/O type SBR process, and runs under anoxic conditions for 3 hours with stirring, and the DO concentration in the anoxic section is controlled at 0.2 mg/L, and then runs under aeration conditions for 8 hours. h, the aeration volume in the aerobic aeration section is kept constant, the DO concentration in the aerobic section is 3-4 mg/L, and the effluent is discharged from the reactor after 30 min of precipitation; The dynamic wave stripping device was used to strengthen the pretreatment. Before the treatment, NaOH was added to the first dosing tank to adjust the pH to 10.5, the stripping time was 5 h, the water intake was 0.4 m³/h, and the air intake was 155 m³/h. h, that is, the gas-liquid ratio is 387.5; The Fenton reaction needs to adjust the pH of the sewage to 3~4, which is conducive to the generation of hydroxyl radicals (•OH), add FeSO ₄ 7H ₂ O and mix with the raw water, then add H ₂ O ₂ , after a sufficient reaction Adjust the pH to about 8 with NaOH, which is conducive to the formation of flocculation and precipitation; A/O-type SBR process has an operation cycle of 12 hours, 2 cycles per day, anoxic stirring time of 3 hours, aeration time of 8 hours, and sedimentation time of 30 minutes. periodic water intake; The aging landfill leachate treatment system includes a sewage water inlet pipe (1), a first dosing tank (2), a first dosing pump (3), a sewage regulating tank (4), a sewage centrifugal pump (5), a pressure gauge ( 6), power wave stripping device (7), reaction circulation box (8), power distribution control cabinet (9), partition plate (10), adjustable speed fan (11), air inlet flowmeter (12), Power wave stripping nozzle (13), wave pipe (14), return pipe (15), drain pipe control valve (16), drain pipe (17), second dosing tank (18), second dosing pump ( 19), regulating tank (20), reaction tank (22), solid dosing device (23), stirring device (24), third dosing tank (25), third dosing pump (26), coagulation tank (27), the fourth dosing tank (29), the fourth dosing pump (30), the sedimentation tank (31), the water outlet valve (32), the sludge discharge valve (33), the A/O type SBR reactor (34 ), air compressor (35), gas flow meter (36), microporous aeration head (37), DO measuring instrument (39), DO probe (40), pH measuring instrument (41), pH probe (42) , vent valve (45); The input end of the water inlet pipe (1) is connected to the landfill leachate in the equalization tank of the landfill, and the output end of the water inlet pipe (1) is connected to the top water inlet of the sewage conditioning tank (4), and the NaOH passes through the first dosing tank ( 2) The first dosing pump (3) is mixed with the landfill leachate in the sewage conditioning tank (4), the output end of the sewage conditioning tank (4) is connected to the sewage centrifugal pump (5), and the landfill leachate is passed through the pressure gauge ( 6) Enter the wave tube (14) of the dynamic wave blowing off device (7), and shoot upwards in a radial swirling flow by the dynamic wave blowing off nozzle (13) inside the wave tube (14), and the high-speed airflow is driven by the adjustable speed fan (11) The air inlet flowmeter (12) is in countercurrent contact with the high-speed rotating liquid flow inside the wave tube (14), and the liquid blown off by the dynamic wave stripping device (7) flows into the reaction circulation box (8). , the reaction circulation box (8) is vertically provided with a partition (10), the top and bottom of the partition (10) and the reaction circulation box (8) are provided with a gap, and the reaction circulation box (8) After the separator (10) in the middle is hydraulically stirred, a part of the liquid is sent to the dynamic wave stripping device (7) by the sewage centrifugal pump (5) again through the return pipe (15) for cyclic stripping treatment, and the dynamic wave stripping device (7) The power distribution control cabinet (9) is installed on the upper part, the drain pipe control valve (16) is opened, and the sewage after the blow-off is discharged from the drain pipe (17) to the adjustment tank (20); The sewage after stripping is mixed with the H ₂ SO ₄ added by the second dosing tank ( 18 ) through the second dosing pump ( 19 ) in the adjustment tank ( 20 ), and the output end of the adjustment tank ( 20 ) is mixed. The reaction tank (22) is connected through a drainage pipe, FeSO ₄ ·7H ₂ O is added into the reaction tank (22) through the solid dosing device (23), and the FeSO ₄ ·7H 2 O is fed into the reaction tank (22) by the stirring device (24) on the reaction tank (22). 7H ₂ O is mixed with sewage, the reaction tank (22) is connected to the coagulation tank (27), and the H ₂ O ₂ enters the coagulation tank (27) through the third dosing tank (25) and the third dosing pump (26). ), and the sewage with uniform Fe ²⁺ is mixed and reacted with a stirring device in the coagulation tank (27), the coagulation tank (27) is connected with the sedimentation tank (31), and the NaOH passes through the fourth dosing tank (29). ), the fourth dosing pump (30) enters the sedimentation tank (31) to adjust the pH of the sewage to about 8, so that the sludge settles, and the supernatant enters the A/O type SBR reactor (34) through the outlet valve (32), The sedimented sludge is discharged through the sludge discharge valve (33); The sewage treated by the Fenton reaction enters the A/O type SBR reactor (34), and is operated under anoxic conditions with stirring by a stirring device for 3 hours. The aeration head (37) is ejected, and the microporous aeration head (37) is located at the inner bottom of the A/O type SBR reactor (34), and runs for 8 hours under aeration conditions, and DO passes through the A/O type SBR reactor (34). The DO probe (40) at the top of the ) is connected to the DO meter (39) for monitoring, and the pH is monitored by the pH probe (42) at the top of the A/O SBR reactor (34) connected to the pH meter (41). The effluent is discharged through a drainage pipe through the outlet valve, and a vent valve (45) is provided at the bottom of the A/O type SBR reactor (34) for venting and discharging sludge.

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