CN215049555U

CN215049555U - Landfill leachate treatment system

Info

Publication number: CN215049555U
Application number: CN202122160218.1U
Authority: CN
Inventors: 谢凯; 刘雄杰; 苏新华
Original assignee: Hunan Seagull Environmental Protection Technology Co ltd
Current assignee: Hunan Seagull Environmental Protection Technology Co ltd
Priority date: 2021-09-08
Filing date: 2021-09-08
Publication date: 2021-12-07
Anticipated expiration: 2031-09-08

Abstract

The utility model discloses a landfill leachate processing system comprises UASB pond, homogeneity pond, AO-MBR pond, first fenton decomposition tank, first bological aerated filter, the fragrant decomposition tank of second, second bological aerated filter, sludge thickening pond and mud filter-pressing pond, the UASB pond the homogeneity pond AO-MBR pond first fenton decomposition tank first bological aerated filter the fragrant decomposition tank of second the bological aerated filter connects gradually. The utility model discloses a landfill leachate processing system replaces to receive filter membrane and reverse osmosis membrane through biochemical multistage alternative treatment, need not to change and washs the filter membrane, does not produce the membrane concentrate, and easy management, easy control, maintenance cost are low, can adapt to the quality of water change condition of landfill yard filtration liquid in different periods, rely on the high-efficient pollution factor of getting rid of the inherent impact resistance adaptability of system, guarantee out water quality of water up to standard.

Description

Landfill leachate treatment system

Technical Field

The utility model relates to a sewage treatment technical field especially relates to a landfill leachate treatment system.

Background

The landfill leachate is a high-concentration complex-component liquid generated under the flow action of precipitation and underground water due to the biochemical degradation effects of compaction, fermentation and the like in the stacking and landfill processes of the garbage.

The landfill leachate has complex water quality and contains various toxic and harmful inorganic matters and organic matters. The organic pollution is detected by technology, and there are more than 99 kinds, and there are 22 kinds which are already listed in the emphasis control lists of national and American environmental protection agency, 1 kind can directly cause cancer, 5 kinds can induce cancer, besides, leachate also contains non-chlorinated aromatic compounds such as benzene, etc., chlorinated aromatic compounds, phosphate, phenolic compounds and aniline compounds, etc., which are difficult to biodegrade. According to practical experience of numerous landfill leachate treatment projects in China and mastered water quality characteristics of landfill leachate, the landfill leachate has the characteristics of high pollutant concentration, complex components, extremely unstable change and the like.

At present, the domestic landfill leachate treatment technology selection follows the technical route of 'pretreatment + biological treatment + advanced treatment' recommended by CJJ150-2010 and HJ 564-2010. However, there are the following problems:

(1) the indexes of main pollutants of the landfill leachate change with the field age of the landfill, particularly the proportion of the later-stage leachate is increased, and how to select a reasonable treatment process is suitable for the water quality change condition of the leachate at different stages; particularly, on the premise of improving the adaptability of the interior of the reaction system to adverse factors, the biological treatment unit reduces the intervention of external control conditions and efficiently removes ammonia nitrogen and total nitrogen by the inherent adaptability of the system.

(2) For the advanced treatment process, at present, particularly before 2008, the advanced treatment of the percolate mostly takes Nanofiltration (NF) and Reverse Osmosis (RO) as main components. Although the membrane method advanced treatment process is adopted, the problem of advanced treatment of a large amount of nonbiodegradable organic matters in the leachate is solved, the water yield can reach 65-75%, and the effluent can reach the standard and be discharged, along with the accumulation of engineering practice, the membrane method advanced treatment of the landfill leachate has the defects that on one hand, the yield of concentrated solution is reduced, the membrane is blocked, repeated cleaning is needed, and even a new membrane is replaced, on the other hand, most of the organic matters in the membrane concentrated solution are nonbiodegradable organic matters, the salinity is high, secondary pollution is easy to form, and the treatment technology is difficult and high in cost.

The foregoing description is provided for general background information and is not admitted to be prior art.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a landfill leachate processing system of non-membrane processing.

The utility model provides a landfill leachate processing system comprises UASB pond, homogeneity pond, AO-MBR pond, first fenton decomposition tank, first bological aerated filter, the fragrant decomposition tank of second, second bological aerated filter, sludge thickening pond and mud filter-pressing pond, the UASB pond the homogeneity pond AO-MBR pond first fenton decomposition tank first bological aerated filter the fragrant decomposition tank of second the bological aerated filter connects gradually.

Further, a first drug feeding port for feeding a Fenton reagent into the first Fenton decomposition tank is formed in the first Fenton decomposition tank; and a second drug feeding port for feeding a Fenton reagent into the second Fenton decomposition tank is formed in the second Fenton decomposition tank.

Furthermore, a third dosing port for dosing a carbon source into the AO-MBR tank is formed in the AO-MBR tank.

Furthermore, a feed inlet of the sludge concentration tank is connected with sludge outlets of the AO-MBR tank, the first Fenton decomposition tank and the second Fenton decomposition tank, and a water outlet of the sludge concentration tank is connected with the homogenizing tank to input supernatant into the homogenizing tank to balance the water quality of the filtrate.

Furthermore, a feed inlet of the sludge pressure filter is connected with a sludge outlet of the sludge concentration tank, and a water outlet of the sludge pressure filter is connected with the homogenizing tank to input the mud pressure water into the homogenizing tank to balance the water quality of the filtrate.

Furthermore, the sludge filter pressing tank is internally provided with at least one of a belt filter press, a plate-and-frame filter press, a box filter press and a vertical filter press.

Furthermore, fans are arranged in the AO-MBR tank, the first biological aerated filter and the second Fenton decomposition tank.

Furthermore, a fourth dosing port for adding a carbon source into the first biological aerated filter is arranged on the first biological aerated filter, and a fifth dosing port for adding a carbon source into the second biological aerated filter is arranged on the second biological aerated filter.

The utility model provides a landfill leachate treatment system decomposes the structure of macromolecule organic matter in the filtration liquid through utilizing UASB pond earlier in order to improve the biodegradability of sewage, the good oxygen of recycling AO-MBR pond nitrifies, the biochemical treatment is carried out to the oxygen deficiency denitrification principle and gets rid of the pollutant, to the material that biochemical treatment is difficult to degrade in the filtration liquid through first fenton decomposition pond application chemical oxidation technique to carry out further processing to sewage, the biochemical treatment is carried out with first aeration biological filter to the assistance again, the filtration liquid is after the primary biological treatment, reentry in the second grade chemical treatment, further get rid of difficult biodegradable organic matter in the filtration liquid, remove the colourity, pass through second aeration biological filter complete denitrification filtration liquid at last, make the filtration liquid finally reach emission standard, replace nanofiltration membrane and reverse osmosis membrane through biochemical multistage alternative treatment, need not to change and wash the filtration membrane, does not produce membrane concentrated solution, is easy to manage and control, has low maintenance cost, can adapt to the water quality change condition of the percolate in different periods of a landfill, efficiently removes pollution factors by depending on the inherent shock resistance adaptability of the system, and ensures the effluent quality to reach the standard.

Drawings

Fig. 1 is the utility model discloses landfill leachate treatment system's schematic structure diagram.

Detailed Description

The following detailed description of the embodiments of the present invention is provided with reference to the accompanying drawings and examples. The following examples are intended to illustrate the invention, but are not intended to limit the scope of the invention.

Referring to fig. 1, a landfill leachate treatment system according to an embodiment of the present invention includes an adjusting tank 10, a UASB (Upflow Anaerobic Sludge Blanket) tank 20, a homogenizing tank 30, an AO-MBR (membrane bioreactor is used in Anaerobic and aerobic environments) tank 40, a first fenton decomposition tank 50, a first Biological Aerated Filter (BAF) 60, a second fenton decomposition tank 70, a second Biological Aerated Filter 80, a Sludge concentration tank 90, a Sludge Filter press tank 91, and a clean water tank 100.

The adjusting tank 10, the UASB tank 20, the homogenizing tank 30, the AO-MBR tank 40, the first Fenton decomposition tank 50, the first biological aerated filter 60, the second Fenton decomposition tank 70, the second biological aerated filter 80 and the clean water tank 100 are connected in sequence. The feed inlet of the sludge concentration tank 90 is connected with the sludge outlets of the AO-MBR tank 40, the first Fenton decomposition tank 50 and the second Fenton decomposition tank 70, and the feed inlet of the sludge press filtration tank 91 is connected with the sludge outlet of the sludge concentration tank 90.

The percolate firstly flows into the regulating tank 10, is temporarily stored in the regulating tank 10, and then flows into the UASB tank 20 after reaching the uniform standard of homogeneous uniform amount. The UASB tank 20 includes a sludge bed 21 and a three-phase separator 22, the sludge bed 21 is located at the lower part of the tank and contains granular sludge or flocculent sludge with high activity and high content. The three-phase separator 22 is located at the upper part of the tank and is composed of a settling zone (not shown), a return slit (not shown) and a gas collecting chamber (not shown), and functions to separate the three phases of gas (biogas), solid (sludge) and liquid. The marsh gas enters the air chamber, the sludge is precipitated in the precipitation area and flows back to the lower part of the UASB pool 20 through the backflow seam, and the liquid is discharged out of the UASB pool 20.

The feed inlet of UASB pond 20 is located the bottom of pond, and the discharge gate is located pond upper portion. The percolate passes upwards through the sludge bed 21 and contacts with sludge particles to carry out anaerobic reaction. Biogas (mainly methane and carbon dioxide) produced under anaerobic conditions causes internal circulation, which is beneficial for the formation and maintenance of granular sludge. Some of the gas formed in the sludge bed rises together with sludge particles and percolate towards the top of the UASB pond 20. The sludge rising to the surface strikes the bottom of the three-phase separator 22, causing degassing of the sludge flocs with attached bubbles. Sludge particles will settle to the surface of the sludge bed 21 after the bubbles are released and the gas is collected in the top plenum of the triphase separator 22. The liquid containing some remaining solids and sludge particles passes through the separator gap into the settling zone. Sludge flocs can flocculate and settle in the settling zone due to the reduced flow rate. Sludge floes that accumulate on the three-phase separator 22 will to some extent exceed the friction it holds on the sloped walls, which will lower the UASB pool 20, which in turn will react with the influent organics.

The percolate treated by the UASB tank 20 flows into the homogenizing tank 30, a water injection port 31 is arranged on the homogenizing tank 30 and used for injecting moisture homogenizing percolate into the homogenizing tank 30, and the homogenized percolate flows into the AO-MBR tank 40. The AO-MBR tank 40 what is equipped with third mouth of dosing 41, third fan 42 and mud outlet (not marked), and the third mouth of dosing is used for throwing the carbon source to the pond in, improves denitrification efficiency. The AO-MBR tank 40 combines a biofilm method and an anaerobic/aerobic process, aerobic nitrification and anaerobic denitrification are cooperated to carry out biochemical treatment, and a third fan 42 is utilized to improve reoxygenation capacity and mixing capacity, so that muddy water in an aerobic area can be mixed more uniformly and sufficient oxygen can be provided.

The leachate is primarily subjected to mud-water separation after being treated by the UASB tank 20, the sludge flows into the sludge compression tank 90 through a sludge outlet, the liquid flows into the first Fenton decomposition tank 50 to perform chemical oxidation treatment on substances which are difficult to degrade in the biochemical treatment, then the leachate is subjected to biochemical treatment by the first biological aerated filter 60 and then enters the second Fenton decomposition tank 70 to remove the chromaticity of the leachate. The percolate flowing out of the second Fenton decomposition tank 70 flows into a second biological aerated filter 80 for final biochemical treatment, and the organic matters in the fully denitrified percolate flows into a clean water tank 100 for temporary storage.

Conventional primary chemical treatment and biochemical decomposition may cause too high workload, even overload, due to too high pollution factors (COD, ammonia nitrogen and total phosphorus) in sewage, so that treatment effect of treatment facilities is reduced, and adjustment of shock resistance adaptability of the whole system is not facilitated, so that energy consumption of chemicals is too high. After the first-stage chemical decomposition and biochemical treatment, part of pollution factors are removed to ensure the efficient operation of treatment facilities, and the second-stage chemical decomposition and biochemical treatment can also ensure the quality of the effluent to reach the standard and be stable.

Secondly, the pollutant indexes in the landfill leachate change along with the field age of the landfill, particularly the treatment difficulty of the later-stage landfill leachate is high, the process requirement is high, the two-stage chemical decomposition and biochemical decomposition are adaptive to the water quality change conditions of the landfill leachate in different stages, the pollution factors are efficiently removed by means of the inherent impact resistance adaptability of the system, and the effluent quality is guaranteed to reach the standard.

In this embodiment, the first fenton decomposition pool 50 is provided with a first drug inlet 51 and a sludge outlet (not shown), and the second fenton decomposition pool 70 is provided with a second drug inlet 71 and a sludge outlet (not shown). The first dosing port 51 and the second dosing port 71 are used for respectively dosing a Fenton reagent, an acid-base regulator and a flocculating agent into the first Fenton decomposition tank 50 and the second Fenton decomposition tank 70, wherein the Fenton reagent is a system which is composed of hydrogen peroxide and ferrous ions and has strong oxidizing property.

After the leachate enters a chemical decomposition tank, adding an acid-base regulator to regulate the pH value of the leachate to 3-5, then adding a Fenton reagent, wherein ferrous ions catalyze hydrogen peroxide to generate hydroxyl radicals with strong oxidizing capability under an acidic condition to decompose the structure of nonbiodegradable organic matters in the leachate, and most of the organic matters are directly mineralized into carbon dioxide and water or converted into micromolecular organic matters. After the reaction is completed, adding an acid-base regulator to regulate the pH value to 6-8, then adding a flocculating agent to generate flocculent precipitates in the percolate so as to form dual functions of oxidation and flocculation. The sediments in the first Fenton decomposition pool 50 and the second Fenton decomposition pool 70 flow into the sludge compression pool 90 through the sludge outlet.

The sludge compression tank 90 collects sludge generated by the first Fenton decomposition tank 50, the second Fenton decomposition tank 70 and the AO-MBR tank 40, a flocculating agent is added into the sludge concentration tank 90 to flocculate and precipitate solid matters in the sludge, and supernatant flows back to the homogenizing tank 30 through a pipeline to dilute the homogeneous percolate. The flocculated sediment in the sludge compression tank 90 flows into a sludge pressure filter 91, and one or more of a belt filter press, a plate-and-frame filter press, a box filter press and a vertical filter press can be arranged in the sludge pressure filter 91. The filter pressing liquid generated after filter pressing is also returned to the homogenizing pool 30 through a pipeline, and the generated mud cake has the water content of about 60 percent and can be mixed with other solid garbage to be burnt or buried.

The first biological aerated filter 60 is internally provided with a first filter material layer 61, a first fan 62 and a fourth feed port 63, and the second biological aerated filter 80 is internally provided with a second filter material layer 81, a second fan 82 and a fifth feed port 83. The leachate enters the biological aerated filter from the bottom of the filter and then passes through the filter material layer, pollutants contained in the water body are intercepted by the filter material layer and are degraded and converted by the organisms attached to the filter material, meanwhile, dissolved organic matters and specific substances are also removed, the generated sludge is retained in the filter layer, and only purified water passes through the filter layer, so that complete biological treatment can be achieved in a closed reactor without arranging a secondary sedimentation tank at the downstream for sludge sedimentation. The fan is positioned above the filter material layer and provides oxygen-increasing aeration. When the leachate influent BOD (Biochemical oxygen demand) concentration is low, a carbon source can be added into the tank through the fourth feeding port 63 and the fifth feeding port 83, so that the denitrification efficiency and the nitrogen removal level are improved.

In this embodiment, the carbon source to be added is methanol, and in other embodiments, acetic acid, sodium acetate, etc. may be used instead.

The utility model provides a landfill leachate treatment system decomposes the structure of macromolecule organic matter in the filtration liquid through utilizing UASB pond 20 earlier in order to improve the biodegradability of sewage, the good oxygen of recycling AO-MBR pond 40 is nitrified, the biochemical treatment is carried out to the oxygen deficiency denitrification principle and is got rid of the pollutant, to the material that biochemical treatment is difficult to degrade in the filtration liquid further handle sewage through first fenton decomposition pond 50 application chemical oxidation technique, it carries out biochemical treatment with first aeration biological filter 60 to be assisted again, the filtration liquid is through the primary biological treatment back, in the secondary chemical treatment of reentrant, further get rid of the difficult biodegradable organic matter in the filtration liquid, get rid of the colourity, at last through the complete denitrification filtration liquid of second aeration biological filter 80, make the filtration liquid finally reach emission standard, replace nanofiltration membrane and reverse osmosis membrane through biochemical multistage alternative treatment, need not to change and wash the filtration membrane, does not produce membrane concentrated solution, is easy to manage and control, has low maintenance cost, can adapt to the water quality change condition of the percolate in different periods of a landfill, efficiently removes pollution factors by depending on the inherent shock resistance adaptability of the system, and ensures the effluent quality to reach the standard.

In the drawings, the size and relative sizes of layers and well regions may be exaggerated for clarity. It will be understood that when an element such as a layer, well, or substrate is referred to as being "formed on," "disposed on," or "located on" another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly formed on" or "directly disposed on" another element, there are no intervening elements present.

In this document, unless expressly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms can be understood in a specific case to those of ordinary skill in the art.

As used herein, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, including not only those elements listed, but also other elements not expressly listed.

As used herein, the ordinal adjectives "first", "second", etc., used to describe an element are merely to identify the element as being similar in nature, and are not intended to imply that the elements so described must be in a given sequence, either temporally, spatially, in ranking, or in other manner.

As used herein, the meaning of "a plurality" or "a plurality" is two or more unless otherwise specified.

In this document, the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", "vertical", "horizontal", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for the sake of clarity and convenience of description of the technical solutions, and thus, should not be construed as limiting the present invention.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. The utility model provides a landfill leachate processing system, its characterized in that comprises UASB pond, homogeneity pond, AO-MBR pond, first fenton decomposition tank, first bological aerated filter, the fragrant decomposition tank of second, second bological aerated filter, sludge thickening pond and mud filter-pressing pond, the UASB pond the homogeneity pond AO-MBR pond first fenton decomposition tank first bological aerated filter the fragrant decomposition tank of second the bological aerated filter connects gradually.

2. The landfill leachate treatment system of claim 1, wherein the first Fenton decomposition tank is provided with a first dosing port for dosing Fenton's reagent into the first Fenton decomposition tank; and a second drug feeding port for feeding a Fenton reagent into the second Fenton decomposition tank is formed in the second Fenton decomposition tank.

3. The landfill leachate treatment system of claim 1, wherein the AO-MBR tank is provided with a third dosing port for dosing a carbon source into the AO-MBR tank.

4. The landfill leachate treatment system of claim 1, wherein the feed inlet of the sludge concentration tank is connected to the sludge outlets of the AO-MBR tank, the first Fenton decomposition tank and the second Fenton decomposition tank, and the water outlet of the sludge concentration tank is connected to the homogenizing tank for feeding supernatant into the homogenizing tank to equalize the quality of the filtrate.

5. The landfill leachate treatment system of claim 4, wherein the feed inlet of the sludge pressure filtration tank is connected to the sludge outlet of the sludge concentration tank, and the water outlet of the sludge pressure filtration tank is connected to the homogenizing tank for feeding sludge pressure water into the homogenizing tank to equalize the quality of the filtrate.

6. The landfill leachate treatment system of claim 5, wherein the sludge filter press tank is provided with at least one of a belt filter press, a plate and frame filter press, a box filter press and a vertical filter press.

7. The landfill leachate treatment system of claim 1, wherein fans are disposed in the AO-MBR tank, the first biological aerated filter and the second Fenton decomposition tank.

8. The landfill leachate treatment system of claim 1, wherein the first biological aerated filter is provided with a fourth dosing port for adding a carbon source into the first biological aerated filter, and the second biological aerated filter is provided with a fifth dosing port for adding a carbon source into the second biological aerated filter.