CN212954728U - Device for treating landfill leachate - Google Patents

Abstract

The invention relates to a device for treating landfill leachate, which structurally comprises an integrated pretreatment device, an ultrasonic cavitation electrocatalysis integrated device and a biological enhancement integrated device which are mutually connected through pipelines, thereby effectively solving the problem that the leachate has no recharge, and directly discharging the leachate to reach the standard; the invention has the advantages of high efficiency of treating the garbage leachate, thorough treatment of the leachate, no secondary pollution to the environment, convenient movement, short installation period of the device, small occupied area, low investment and operation cost, wide market application prospect and convenient popularization and use, and is completely skid-mounted integrated devices.

Description

Device for treating landfill leachate

Technical Field

The invention relates to the technical field of sewage treatment, in particular to a device for treating landfill leachate.

Background

The landfill leachate is mainly prepared by mixing urban domestic garbage and rainwater into a concentrated solution, and the water body is black or brown and has foul smell which affects the surrounding environment. The landfill leachate contains a large amount of humic substances, humic acid and other macromolecular degradation-resistant organic matters, inorganic salts, metal ions and the like, and has biotoxicity, so that the treatment difficulty is high, the cost is high, and the standard treatment is difficult to realize by a single treatment method and a conventional treatment technology.

The prior art generally adopts the process flow of materialization (pretreatment), biological treatment and materialization (advanced treatment) for treating the landfill leachate. The prior advanced treatment generally adopts a combined process of nanofiltration, ultrafiltration and reverse osmosis, has incomplete treatment and reduces the percolate quantity of a landfill due to the fact that concentrate needs recharging treatment, but greatly improves the concentration of pollutants, and cannot fundamentally solve the pollution problem of the landfill leachate. The materialization method is as follows: the iron-carbon micro-electrolysis method, the Fenton reagent oxidation method, the ozone oxidation method and the like not only have complex operation and difficult process control, but also have large equipment investment, high energy consumption and high wastewater treatment cost, and the salt content of the wastewater is further increased after the treatment.

Along with the technological progress, the electrocatalysis method is more and more emphasized by people. Compared with other physical and chemical methods, the electrocatalysis method has multiple advantages, such as no additional redox agent is needed, no or little secondary pollution is generated, the controllability is strong, the reaction condition is mild, the instrument and equipment and the operation thereof are simpler, the cost is lower, the electrocatalysis method can be used as a single treatment mode, and can be combined with other treatment processes, and the like, so that the further research of the electrocatalysis method is helpful for solving the defects and the shortcomings of the prior art.

Disclosure of Invention

The invention aims to provide a device for treating landfill leachate, which solves the technical problems of incomplete treatment, difficult standard reaching, high cost and the like of the landfill leachate in the prior art.

In order to achieve the above purpose, the following technical scheme is provided:

a device for treating landfill leachate structurally comprises an integrated pretreatment device, an ultrasonic cavitation electrocatalysis integrated device and a biological enhancement integrated device which are connected with each other through pipelines; the integrated pretreatment device consists of a water inlet and outlet area, a flocculation dosing sedimentation area, a nano air flotation deslagging area and a sedimentation clarification area, and the ultrasonic cavitation electrocatalysis integrated device comprises a container body, an ultrasonic cavitation generator, an external power supply, an automatic scraper and an automatic purging device; the biological strengthening integrated device comprises an anoxic zone, a biological aeration strengthening zone and a water drop backflow zone.

As a preferred scheme, the water inlet and outlet area is divided into a water inlet area and a water outlet area which are respectively arranged at two ends of the integrated pretreatment device, the dosing flocculation settling area is positioned at one side of the water inlet area, the nano air flotation deslagging area is positioned between the dosing flocculation settling area and the sedimentation settling area, the sedimentation settling area is connected with the water outlet area, and the water inlet area, the dosing flocculation settling area, the nano air flotation deslagging area, the sedimentation settling area and the water outlet area are separated by overflow plates.

As the preferred scheme, the district is equipped with the equalizing basin intakes, flocculation adds the medicine subsides the district and is equipped with dosing pump and agitator, and integration preprocessing device bottom is equipped with the mud pipe, nanometer air supporting slagging-off district bottom is equipped with nanometer bubble generator, the top of settling clarification district sets up automatic hydraulic pressure scraper blade, the district of intaking is equipped with the water inlet, the district of going out water is equipped with a water outlet mouthful and arranges sediment mouthful one.

As a preferred scheme, a plurality of pairs of cathode and anode plates are arranged in a container body of the ultrasonic cavitation integrated device, an automatic scraper and an automatic purging device are arranged at the tops of the cathode and anode plates, the ultrasonic cavitation generator is arranged at the front water inlet end of the ultrasonic cavitation electrocatalysis integrated device and is coupled with the cathode and anode in the container body, and a water inlet baffle plate is arranged between the ultrasonic cavitation generator and the cathode and anode in the container body; the external power supply is positioned outside the ultrasonic cavitation integrated device, and the rear part of the ultrasonic cavitation integrated device is provided with a water outlet II and a slag discharge outlet II.

Preferably, the distance between the anode plate and the cathode plate is (2-2.5) cm, the current density is (2-25) mA/cm2, the anode plate is made of superconducting material and titanium cobalt oxide catalyst, and the cathode plate is made of 316L.

Preferably, the biological enhancement integrated device comprises an anoxic zone, a biological aeration enhancement zone and a water drop backflow zone, the anoxic zone is connected with a water inlet of the biological enhancement integrated device, the biological aeration enhancement zone is positioned on one side of the anoxic zone and is separated by an overflow plate, the water drop backflow zone is positioned on the other side of the anoxic zone and is separated by an overflow plate, and a water outlet III and a slag discharge outlet III are arranged at the rear part of the biological enhancement integrated device.

As a preferred scheme, the anoxic zone is provided with a stirrer and a lift pump, the biological aeration strengthening zone is provided with a Roots blower and an aeration pipeline, the drop water reflux zone is provided with a water passing port and a reflux port, the height difference between the water passing port and the reflux port is 15cm, and the drop water reflux zone is filled with suspended fillers.

As a preferred scheme, the aeration pipeline is connected with the Roots blower, an aluminum oxide sintering pipe is used as a material, laser drilling is adopted on the aeration pipeline, the aperture is 0.1 mu m, and the hole distance is (2-4) mm.

An apparatus for treating landfill leachate, comprising the steps of:

s1, enabling the landfill leachate to enter a regulating reservoir of a water inlet area of the integrated pretreatment device through a water inlet to regulate the pH value;

s2, enabling the garbage percolate with the adjusted PH to enter a flocculation dosing sedimentation area, dosing through a dosing pump, uniformly stirring by using a stirrer, performing flocculation treatment, settling sludge, discharging through a sludge discharge pipe, performing dehydration treatment, and enabling upper-layer liquid to enter a nano air flotation deslagging area through an overflow plate;

s3, generating micro bubbles with the diameter of 80-180 nm by a nano bubble generator to float and surface suspended matters and floating slag of the liquid, then enabling the floating matters and floating slag to enter a sedimentation and clarification tank through an overflow plate, scraping the suspended matters, floating slag and foam to a slag outlet by an automatic hydraulic scraper at the top of the sedimentation and clarification tank to be discharged, and enabling supernatant to enter an ultrasonic cavitation and electrocatalysis integrated device;

s4, enabling the supernatant to enter an ultrasonic cavitation generator, and enabling the supernatant to enter the container body through a water inlet baffle plate after the supernatant is acted by the ultrasonic cavitation generator;

s5, enabling the supernatant to act through a plurality of negative and positive electrodes to break an organic matter connecting ring so as to effectively degrade, and simultaneously removing foam generated in a negative and positive electrode reaction area through the combined action of an automatic scraper and an automatic purging device;

s6, enabling the supernatant subjected to the treatment of the negative and positive electrodes to flow out through a water outlet, pumping the supernatant into an anoxic zone of the biological enhancement integrated device, and carrying out anoxic treatment;

s7, introducing the supernatant subjected to the anoxic treatment into a biological aeration strengthening zone for aeration treatment, and then introducing the supernatant into a drop water backflow zone through a water gap;

and S8, discharging the water part entering the water drop backflow area through a water outlet, and performing recirculation treatment on the water part by backflow through a backflow port.

The invention has the beneficial effects that:

1. the device and the related process are utilized to treat the landfill leachate, the problem that the leachate has no recharge is effectively solved, and the leachate treated by the method can directly reach the discharge standard;

2. the invention adopts skid-mounted integrated devices, is convenient to move, and has short installation period, small floor area and low investment and operation cost;

3. by adopting the ultrasonic cavitation and electrocatalytic oxidation coupling technology, visible light is assisted while the action of the negative and positive electrodes is carried out, the oxidizing capability is stronger, and the removal rate of organic matters is higher;

4. the adopted biological strengthening integrated device is ingenious in design, effectively fuses oxygen deficiency and oxygen deficiency, and meanwhile, the aeration pipe is sintered by adopting aluminum oxide, so that the aeration effect is good, the service cycle is long, and the standard reaching guarantee of organic matter removal is effectively realized;

5. the method for treating the landfill leachate can not cause secondary pollution to the environment, has wide market application prospect and is convenient to popularize and use.

Drawings

FIG. 1 is a schematic structural view of an integrated pretreatment device;

FIG. 2 is a schematic structural diagram of an ultrasonic cavitation electrocatalysis integrated device;

FIG. 3 is a schematic structural diagram of the integrated bio-augmentation device;

FIG. 4 is a schematic view of the overall structure of the present invention;

the references in the drawings are: 1-water inlet area, 2-adjusting tank, 3-flocculation drug-adding settling area, 4-nano air flotation deslagging area, 5-sedimentation clarification tank, 6-sludge discharge pipe, 7-drug adding pump, 8-nano bubble generator, 9-automatic hydraulic scraper, 10-first slag discharge port, 11-water outlet area, 12-first water outlet, 13-water inlet, 14-exhaust port, 15-Roots blower, 16-aeration pipe, 17-lift pump, 18-stirrer, 19-overflow plate, 20-return port, 21-first water outlet, 22-second water outlet, 23-second slag discharge port, 24-biological aeration strengthening area, 25-anoxic area, 26-water drop return area, 28-second water outlet, 30-container body, 31-positive and negative electrode plate, 32-three slag discharge openings, 33-three water outlets, 34-an ultrasonic cavitation generator, 35-a water inlet baffle plate, 36-an automatic blowing and washing device, 37-an automatic scraper and 38-a connecting pipeline between devices

Detailed Description

A device for treating landfill leachate structurally comprises an integrated pretreatment device, an ultrasonic cavitation electrocatalysis integrated device and a biological enhancement integrated device which are connected with each other through pipelines; the integrated pretreatment device consists of a water inlet and outlet area, a flocculation dosing sedimentation area 3, a nano air flotation deslagging area 4 and a sedimentation clarification area 5, and the ultrasonic cavitation electrocatalysis integrated device comprises a container body 30, an ultrasonic cavitation generator 34, an external power supply, an automatic scraper 37 and an automatic purging device 36; the biological enhancement integrated device comprises an anoxic zone 25, a biological aeration enhancement zone 24 and a water drop return zone 26.

Wherein, business turn over water is distinguished into water inflow region 1 and play water zone 11, arranges in the both ends of integration preprocessing device separately, adds medicine flocculation and precipitation district 3 and is located water inflow region one side, and nanometer air supporting deslagging area 4 is located between medicine flocculation and precipitation district 4 and the clarification district 5 of settling, and the clarification district 5 of settling links to each other with play water zone 11, and water inflow region 1, add medicine flocculation and precipitation district 3, nanometer air supporting deslagging area 4, the clarification district 5 of settling and play water zone 11 are separated through the overflow plate.

The device comprises a water inlet area 1, a nano air flotation deslagging area 4, a sedimentation clarification area 5, a nano air flotation sedimentation area 2, a chemical dosing pump 7, a chemical dosing pump, a stirrer, a sludge discharge pipe 6, a nano bubble generator 8, an automatic hydraulic scraper 9, an automatic control reciprocating slag scraping operation mode and a reciprocating circulation completion mode, wherein the water inlet area 1 is provided with an adjusting tank 2, the chemical dosing flocculation sedimentation area 4 is provided with a chemical dosing pump 7 and the stirrer, the bottom of the integrated pretreatment device is provided with the sludge discharge pipe 6, the bottom of; the water inlet area 1 is provided with a water inlet, and the water outlet area is provided with a first water outlet 12 and a first slag discharge port 10.

The ultrasonic-cavitation electrocatalysis integrated device comprises a container body 30, a plurality of pairs of cathode and anode plates 31 are arranged in the container body 30, automatic scrapers 37 and automatic purging devices 36 are arranged on the tops of the cathode and anode plates 31, the automatic scrapers 37 adopt an automatic control circulation reciprocating foam scraping operation mode, one reciprocating circulation is completed every 2 minutes, the automatic purging devices 36 adopt a timing automatic control mode, and automatic purging is performed every 10 seconds; the ultrasonic cavitation generator 34 is designed in a range of 20-100KHZ, is arranged at the front water inlet end of the ultrasonic cavitation integrated device, is coupled with the positive and negative electrodes in the container body 30, and is provided with a water inlet baffle plate 35 between the two; the external power supply is positioned outside the ultrasonic cavitation electrocatalysis integrated device, and the rear part of the ultrasonic cavitation electrocatalysis integrated device is provided with a second water outlet 33 and a second slag discharge port 32.

The distance between the positive electrode plate and the negative electrode plate 31 is (2-2.5) cm, the current density is (2-25) mA/cm2, the electrode plates are flat plates with certain specification and size, the positive electrode plate is made of glass embedded superconducting material and titanium cobalt oxide catalyst, and the negative electrode plate is made of 316L.

The biological enhancement integrated device comprises an anoxic zone 25, a biological aeration enhancement zone 24 and a water drop backflow zone 26, wherein the anoxic zone 25 is connected with a water inlet of the biological enhancement integrated device, the biological aeration enhancement zone 24 is positioned on one side of the anoxic zone 25 and is separated by an overflow plate 19, the water drop backflow zone 26 is positioned on the other side of the anoxic zone 25 and is separated by the overflow plate 19, an exhaust port 14 is arranged at the top of the biological enhancement integrated device, and a water outlet III 22 and a slag discharge port III 23 are arranged at the rear part of the biological enhancement integrated device.

Wherein, the anoxic zone 25 is provided with a stirrer 18 and a lift pump 17, the biological aeration strengthening zone 24 is provided with a Roots blower 15 and an aeration pipeline 16, the dissolved oxygen of the anoxic zone 25 is controlled to be less than 0.5mg/L, and the dissolved oxygen of the biological aeration strengthening zone 24 is controlled to be (4-5) mg/L; the drop water return area 26 is provided with a water passing opening 21 and a return opening 20, the height difference between the water passing opening 21 and the return opening 20 is 15cm, and the drop water return area 26 is filled with suspended fillers.

Wherein the aeration pipeline 26 is connected with the Roots blower 15 and is made of an aluminum oxide sintered pipe, and laser drilling is adopted on the aeration pipeline, the aperture is 0.1 mu m, and the hole distance is (2-4) mm.

An apparatus for treating landfill leachate, which comprises the following process steps:

s1, enabling the landfill leachate to enter a regulating tank 2 of a water inlet area 1 of the integrated pretreatment device through a water inlet to regulate the pH value;

s2, enabling the garbage percolate with the adjusted PH to enter a flocculation dosing sedimentation region 3, dosing through a dosing pump 7, uniformly stirring by using a stirrer, performing flocculation treatment, settling sludge, discharging through a sludge discharge pipe 6, performing dehydration treatment, and enabling upper-layer liquid to enter a nano air flotation deslagging region 4 through an overflow plate 19;

s3, generating micro bubbles with the diameter of 80-180 nm by a nano bubble generator 8 to float and surface suspended matters and floating slag of liquid, then enabling the floating matters and floating slag to enter a sedimentation and clarification area through an overflow plate, scraping the suspended matters, floating slag and foam to a slag discharge port through an automatic hydraulic scraper 9 at the top of the sedimentation and clarification area 5 to be discharged, and pumping supernatant liquid in a water outlet area 11 into an ultrasonic cavitation electro-catalysis integrated device through a lifting pump;

s4, enabling the supernatant to enter an ultrasonic cavitation generator, and enabling the supernatant to enter the container body 30 through a water inlet baffle plate 35 after the supernatant is acted by the ultrasonic cavitation generator 34;

s5, enabling the supernatant to be acted by the plurality of positive and negative electrode plates 31 to enable organic matters to be subjected to ring and chain scission so as to be effectively degraded, and simultaneously discharging foams generated in the positive and negative electrode reaction area through the second slag discharge port 32 under the combined action of the automatic scraper 37 and the automatic purging device 36;

s6, enabling the supernatant subjected to the treatment of the negative and positive electrodes to flow out through a second water outlet 33, pumping the supernatant into an anoxic zone 25 of the biological enhancement integrated device, and performing anoxic treatment;

s7, introducing the supernatant subjected to the anoxic treatment into a biological aeration strengthening zone 24 for aeration treatment, and then introducing the supernatant into a drop water return zone 26 through a first water gap 21;

s8, the water part entering the water drop backflow area 26 enters the water outlet III 22 through the water passing opening II 28 to be discharged, and the water part returns through the backflow opening 20 to be recycled.

Example 1

The treatment capacity of landfill leachate of a certain plant in Heilongjiang province is 30m3/d, the COD is 30000-50000mg/L, the ammonia nitrogen is 1200-2000mg/L, the pH is 8.2, the total nitrogen is 3200-3500mg/L, and the chloride ion is 6200 mg/L. And (2) introducing the landfill leachate into an integrated pretreatment device, allowing clear liquid to enter a nano air floatation deslagging area 4 after flocculation precipitation and decoloration layering of the integrated pretreatment device, deslagging and defoaming, lifting the clear liquid to an ultrasonic cavitation electrocatalysis integrated device through a pump, carrying out oxidation treatment, controlling the current density to be 8-10mA/cm2 by controlling the ultrasonic frequency to be 40KHZ, electrolyzing for 150min, and reducing the COD to be less than 10000mg/L and the ammonia nitrogen to be less than 700 mg/L at the stage.

And (3) introducing the landfill leachate into a biological enhancement integrated device for biochemical degradation treatment until the COD of the leachate is reduced to 500mg/L, the ammonia nitrogen is reduced to below 25mg/L, and the total nitrogen is reduced to below 200mg/L, so that the requirement of entering an urban sewage plant is met. The effluent is further guided into a secondary ultrasonic cavitation electrocatalysis integrated device, COD (chemical oxygen demand) of the effluent is reduced to 100mg/L, ammonia nitrogen is reduced to below 25mg/L, total nitrogen is reduced to below 40mg/L, and the water quality reaches the second standard in the ' pollution control Standard for municipal solid waste landfill ' (GB16889-2008) '. The water quality conditions of the inlet water and the outlet water of each process are shown in the following table:

unit: mg/l

Example two:

30m3/d of landfill leachate of a certain plant in Jilin province, 2600-5000mg/L of COD, 800-1200mg/L of ammonia nitrogen, 7.9 of pH7, 1200-2000mg/L of total nitrogen and 5960mg/L of chloride ions. And (2) introducing the landfill leachate into an integrated pretreatment device, allowing clear liquid to enter a nano air floatation deslagging area 4 after flocculation precipitation and decoloration layering of the integrated pretreatment device, deslagging and defoaming, lifting the clear liquid to an ultrasonic cavitation electrocatalysis integrated device through a pump, carrying out oxidation treatment, controlling the current density to be 8-10mA/cm2 by controlling the ultrasonic frequency to be 30KHZ, electrolyzing for 120min, and reducing the COD to be below 800mg/L and the ammonia nitrogen to be below 500mg/L at the stage.

The landfill leachate is led into a biological strengthening integrated device for biochemical degradation treatment until the COD of the leachate is reduced to 100mg/L, the ammonia nitrogen is reduced to below 25mg/L, the total nitrogen is reduced to below 40mg/L, and the water quality reaches the second standard of the pollution control Standard of the domestic refuse landfill (GB 16889-2008). The water quality conditions of the inlet water and the outlet water of each process are shown in the following table:

unit: mg/l

Processing stage names	COD	Ammonia nitrogen	Total nitrogen
				Inflow water	3100	1090	1980
Pretreatment integrated device	1980	790	1280
				Ultrasonic air-conditioner electro-catalysis integrated device (first level)	680	190	298
Bioaugmentation integrated device	78	18	35

The techniques and principles of the present invention have been described above in connection with specific embodiments. These descriptions are only used for the purpose of illustrating the technology and principles of the present invention and should not be construed in any way as limiting the scope of the invention. Based on the explanations herein, those skilled in the art will be able to conceive of other embodiments of the present invention without inventive effort, which would fall within the scope of the present invention.

Claims (8)

1. A device for treating landfill leachate is characterized by structurally comprising an integrated pretreatment device, an ultrasonic cavitation electrocatalysis integrated device and a biological strengthening integrated device which are connected with each other through pipelines; the integrated pretreatment device consists of a water inlet and outlet area, a flocculation dosing sedimentation area, a nano air flotation deslagging area and a sedimentation clarification area, and the ultrasonic cavitation electrocatalysis integrated device comprises a container body, an ultrasonic cavitation generator, an external power supply, an automatic scraper and an automatic purging device; the biological strengthening integrated device comprises an anoxic zone, a biological aeration strengthening zone and a water drop backflow zone.

2. The apparatus of claim 1, wherein the water inlet and outlet regions are divided into a water inlet region and a water outlet region, and are disposed at two ends of the integrated pre-treatment apparatus, the drug-adding flocculation settling region is disposed at one side of the water inlet region, the nano air flotation deslagging region is disposed between the drug-adding flocculation settling region and the sedimentation clarification region, the sedimentation clarification region is connected to the water outlet region, and the water inlet region, the drug-adding flocculation settling region, the nano air flotation deslagging region, the sedimentation clarification region and the water outlet region are separated by an overflow plate.

3. The device for treating landfill leachate according to claim 2, wherein the water inlet zone is provided with a regulating tank, the flocculation chemical adding sedimentation zone is provided with a chemical adding pump and a stirrer, the bottom of the integrated pretreatment device is provided with a sludge discharge pipe, the bottom of the nano air flotation deslagging zone is provided with a nano bubble generator, the top of the sedimentation clarification zone is provided with an automatic hydraulic scraper, the water inlet zone is provided with a water inlet, and the water outlet zone is provided with a first water outlet and a first slag discharge port.

4. The device for treating landfill leachate according to claim 1, wherein a plurality of pairs of anode and cathode plates are installed in the container body of the ultrasonic cavitation electrocatalysis integrated device, an automatic scraper and an automatic purging device are installed on the tops of the anode and cathode plates, the ultrasonic cavitation generator is installed at the front water inlet end of the ultrasonic cavitation integrated device and coupled with the anode and cathode electrodes in the container body, and a water inlet baffle plate is arranged between the ultrasonic cavitation generator and the anode and cathode electrodes; the external power supply is positioned outside the ultrasonic cavitation electrocatalysis integrated device, and the rear part of the ultrasonic cavitation electrocatalysis integrated device is provided with a water outlet II and a slag discharge outlet II.

5. The apparatus for treating landfill leachate according to claim 4, wherein the spacing between the anode and cathode plates is (2-2.5) cm, and the current density is (2-25) mA/cm²The anode plate is made of superconducting material and a titanium cobalt oxide catalyst, and the cathode plate is made of 316L.

6. The device for treating landfill leachate according to claim 1, wherein the anoxic zone is connected to the water inlet of the biological enhancement integrated device, the biological aeration enhancement zone is located on one side of the anoxic zone and is separated by an overflow plate, the drop water return zone is located on the other side of the anoxic zone and is separated by an overflow plate, and the rear part of the biological enhancement integrated device is provided with a third water outlet and a third slag outlet.

7. The apparatus as claimed in claim 6, wherein the anoxic zone is equipped with a stirrer and a lift pump, the biological aeration strengthening zone is equipped with a Roots blower and an aeration pipeline, the drop water reflux zone is equipped with a water passing port and a reflux port, the height difference between the water passing port and the reflux port is 15cm, and the drop water reflux zone is filled with suspended filler.

8. The apparatus as claimed in claim 7, wherein the aeration pipe is connected to the Roots blower and made of sintered alumina pipe, and the aeration pipe is laser-perforated with a diameter of 0.1 μm and a distance of 2-4 mm.

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