A new type of domestic waste leachate membrane concentration evaporation pretreatment device
A novel landfill leachate pretreatment device, employing multi-stage oxidation, coagulation, and sedimentation, solves the problem of poor treatment performance of existing devices, achieving effective removal of pollutants from wastewater and improving evaporation efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NANNING SANFENG ENERGY CO LTD
- Filing Date
- 2025-07-22
- Publication Date
- 2026-07-14
AI Technical Summary
Existing landfill leachate concentrate pretreatment devices are unable to effectively reduce pollutant concentrations and improve biodegradability, resulting in poor subsequent treatment effects.
A novel pretreatment device for the membrane concentration and evaporation of leachate from municipal solid waste was designed. Through multi-stage oxidation, coagulation and sedimentation treatment, including a primary oxidation tank, a secondary oxidation tank, multiple mixing tanks and a flocculation tank, combined with a paddle mixer and a frame reaction mixer, multiple mixing and sedimentation of the drugs are achieved. Finally, large particles are further filtered out by a bag filter.
It significantly reduces COD content in wastewater by 45% and hardness by 50%, slows down scaling in triple-effect evaporators, and improves evaporation efficiency.
Smart Images
Figure CN224493954U_ABST
Abstract
Description
Technical Field
[0001] This utility model specifically relates to the field of leachate pretreatment technology, and more specifically to a novel pretreatment device for municipal solid waste leachate before membrane concentration and evaporation. Background Technology
[0002] Pretreatment of waste concentrate is an important step in the waste treatment process, aiming to reduce the concentration of pollutants in the concentrate, improve its biodegradability, and create conditions for subsequent treatment.
[0003] Chinese Patent Publication No. CN216711783U discloses a pretreatment device for landfill leachate concentrate. It includes a concentrate storage tank, a dosing assembly positioned above the concentrate storage tank, a stirring assembly positioned on the side wall of the concentrate storage tank, a flotation extraction assembly positioned within the concentrate storage tank, an air flotation machine connected to the concentrate storage tank via the flotation extraction assembly, and a scraping assembly positioned on top of the air flotation machine.
[0004] The pretreatment device in the aforementioned patent mainly performs sedimentation treatment on the concentrate, but this method cannot achieve the desired pretreatment effect. Utility Model Content
[0005] The purpose of this invention is to provide a novel pretreatment device for municipal solid waste leachate before membrane concentration and evaporation. Through multiple mixing and sedimentation of chemicals, the wastewater quality is improved, ensuring the effective treatment of the subsequent triple-effect evaporator; thus solving the technical problems mentioned in the background art.
[0006] To achieve the above objectives, this utility model provides the following technical solution:
[0007] A novel pretreatment device for municipal solid waste leachate before membrane concentration and evaporation includes a primary oxidation tank connected to a primary mixing tank; the primary mixing tank connected to a primary flocculation tank; the primary flocculation tank connected to a primary sedimentation tank; and the primary sedimentation tank connected to a secondary oxidation tank.
[0008] The secondary oxidation tank is connected to the secondary mixing tank; the secondary mixing tank is connected to the secondary flocculation tank; the secondary flocculation tank is connected to the secondary sedimentation tank; and the secondary sedimentation tank is connected to the transition tank.
[0009] As a further technical solution of this utility model, a drain pipe is provided on one side of the lower end of the primary oxidation tank; the primary oxidation tank is L-shaped and has three first partitions inside, thereby forming four primary oxidation chambers; and an overflow groove is provided on the first partition between every two adjacent oxidation chambers.
[0010] As a further technical solution of this utility model, the primary mixing tank and the secondary mixing tank are respectively provided with a first folding paddle mixing agitator and a second folding paddle mixing agitator.
[0011] The primary flocculation tank and the secondary flocculation tank are respectively equipped with a first frame reaction agitator and a second frame reaction agitator.
[0012] As a further technical solution of this utility model, a drain pipe is provided on one side of the lower end of the secondary oxidation tank; the secondary oxidation tank.
[0013] As a further technical solution of this utility model, the secondary oxidation tank is arranged in an L-shape, and has three second baffles inside, thereby forming four secondary oxidation chambers; and each second baffle between two adjacent oxidation chambers has an overflow groove.
[0014] As a further technical solution of this utility model, both the primary oxidation tank and the secondary oxidation tank are provided with perforated pipes at the bottom of the tank; the perforated pipes at the bottom of the tank are connected to the air pipes; and the primary oxidation tank is also connected to the RO concentrate pipe.
[0015] As a further technical solution of this utility model, both the primary sedimentation tank and the secondary sedimentation tank are equipped with honeycomb packing material, and a packing tube is provided in the middle of the honeycomb packing material.
[0016] As a further technical solution of this utility model, a transition pool lift pump is provided on one side of the transition pool, wherein the liquid inlet end of the transition pool lift pump is connected to the transition pool, and its liquid outlet end is connected to the triple-effect evaporator.
[0017] As a further technical solution of this utility model, the perforated pipe at the bottom of the pool is provided with multiple perforations, and each pair of perforations is inclined at 45 degrees.
[0018] Compared with the prior art, the beneficial effects of this utility model are:
[0019] 1. In this invention, the membrane concentrate is first pumped from the storage tank into the primary oxidation tank via a booster pump and then into the primary oxidation tank for advanced oxidation. After oxidation, it is transported to the primary mixing tank for mixing, where a large amount of suspended sludge is generated. Subsequently, it is captured by adding flocculation in the primary flocculation tank and then discharged into the primary sedimentation tank for settling. After settling and removing particulate matter in the secondary mixing tank, secondary flocculation tank, and secondary sedimentation tank, the entire pretreatment process is completed. The pretreated concentrate then enters the downstream transition tank and is then pumped into the triple-effect evaporator for evaporation and volume reduction treatment via a booster pump.
[0020] After two stages of oxidation, coagulation, and sedimentation, the concentrated liquid enters the transition tank for water volume adjustment to meet the actual production needs of the subsequent triple-effect evaporation process. The concentrated liquid exiting the transition tank (with the addition of ammonium chloride to slow down scaling and increase evaporation rate) is further filtered by a bag filter to remove excess water and then oxidized in the secondary oxidation tank 5.
[0021] 2. This utility model is designed to remove COD and calcium and magnesium ions from wastewater. After treatment in the entire process section, the COD content in the wastewater can be reduced by about 45%, and the hardness can be reduced by at least 50%. This can greatly slow down the scaling rate of the subsequent triple-effect evaporator and improve the evaporation efficiency. Attached Figure Description
[0022] Figure 1 This is a schematic diagram of the planar structure of this utility model.
[0023] Figure 2 This utility model Figure 1 A schematic diagram of the internal structure.
[0024] Figure 3 This utility model Figure 1 AA sectional view.
[0025] Figure 4 This utility model Figure 2 BB cross-sectional view.
[0026] Figure 5 This utility model Figure 1 CC section view.
[0027] Figure 6 This utility model Figure 1 DD sectional view.
[0028] Figure 7 This utility model Figure 1 EE sectional view.
[0029] Figure 8 This is a schematic diagram of the perforated pipe at the bottom of the pool in this utility model.
[0030] Figure 9 This is a schematic diagram of the perforated pipe opening method at the bottom of the pool in this utility model.
[0031] In the diagram: 1-Primary oxidation tank, 2-Primary mixing tank, 3-Primary flocculation tank, 4-Primary sedimentation tank, 5-Secondary oxidation tank, 6-Secondary mixing tank, 7-Secondary flocculation tank, 8-Secondary sedimentation tank, 9-Transition tank, 10-Triple-effect evaporator, 11-First baffle, 12-Second baffle, 13-RO concentrate pipeline, 14-Air pipeline, 15-Perforated pipe at the bottom of the tank, 16-First pleated mixing agitator, 17-First frame reaction agitator, 18-Second pleated mixing agitator, 19-Second frame reaction agitator, 20-Transition tank lift pump, 21-Drain pipe, 22-Honeycomb packing, 23-Packing pipe. Detailed Implementation
[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0033] Please see Figure 1-9 In this embodiment of the present invention, a novel pretreatment device for membrane concentration and evaporation of leachate from municipal solid waste includes a primary oxidation tank 1, which is connected to a primary mixing tank 2; the primary mixing tank 2 is connected to a primary flocculation tank 3; the primary flocculation tank 3 is connected to a primary sedimentation tank 4; and the primary sedimentation tank 4 is connected to a secondary oxidation tank 5.
[0034] The secondary oxidation tank 5 is connected to the secondary mixing tank 6; the secondary mixing tank 6 is connected to the secondary flocculation tank 7; the secondary flocculation tank 7 is connected to the secondary sedimentation tank 8; and the secondary sedimentation tank 8 is connected to the transition tank 9.
[0035] By adopting the above technical solution, the RO concentrate needs to go through a total of 8 stages in the pretreatment system, namely primary oxidation, primary coagulation, primary sedimentation, secondary oxidation, secondary coagulation, secondary sedimentation, water volume adjustment, and bag filtration.
[0036] The membrane concentrate is first pumped from the storage tank into the primary oxidation tank 1 via the RO concentrate pipeline 13 by the booster pump for advanced oxidation. After oxidation, it is transported to the primary mixing tank 2 for mixing. The concentrate will produce a lot of suspended sludge. Then, it is added to the primary flocculation tank 3 for flocculation and capture, and then discharged into the primary sedimentation tank 4 for settling and discharge. This process is called primary coagulation + primary sedimentation.
[0037] Then, after settling and removing particulate matter in the secondary mixing tank 6, secondary flocculation tank 7, and secondary sedimentation tank 8, the entire pretreatment process is completed. The concentrated liquid after pretreatment continues to enter the downstream transition tank 9, and then is pumped into the triple-effect evaporator 10 by the transition tank lift pump 20 for evaporation and volume reduction treatment.
[0038] After two stages of oxidation, coagulation, and sedimentation, the concentrated liquid enters the transition tank for water volume adjustment to meet the actual production needs of the subsequent triple-effect evaporation process. The concentrated liquid exiting the transition tank (with the addition of ammonium chloride to slow down scaling and increase evaporation rate) is further filtered by a bag filter to remove excess water and then oxidized in the secondary oxidation tank 5.
[0039] This pretreatment process is designed for the "concentrated liquid" produced after our leachate treatment. Its main purpose is to remove COD and calcium and magnesium ions from the wastewater. After the entire process, the COD content in the wastewater can be reduced by about 45%, and the hardness can be reduced by at least 50%, which can greatly slow down the scaling rate of the subsequent triple-effect evaporator and improve the evaporation efficiency.
[0040] In this embodiment, a drain pipe 21 is provided on one side of the lower end of the primary oxidation tank 1; the primary oxidation tank 1 is L-shaped and has three first partitions 11 inside, thereby forming four primary oxidation chambers; and each first partition 11 between two adjacent oxidation chambers has an overflow groove.
[0041] The secondary oxidation tank 5 is L-shaped and has three second partitions 12 inside, thus forming four secondary oxidation chambers; and each second partition 12 between two adjacent oxidation chambers has an overflow groove.
[0042] The four chambers of the primary oxidation tank 1 and the secondary oxidation tank 5 are, in sequence, a concentrated sulfuric acid dosing tank, a sodium hydroxide dosing tank, a hydrogen peroxide dosing tank, and a ferrous sulfate dosing tank. This achieves further oxidation of the wastewater.
[0043] In this embodiment, the primary mixing tank 2 and the secondary mixing tank 6 are respectively equipped with a first flared mixing agitator 16 and a second flared mixing agitator 18; the mixing agitators are used to achieve full aeration of the mixing tank, which increases the oxygen contact area of the wastewater and improves the mixing effect between additives, drugs and wastewater.
[0044] The primary flocculation tank 3 and the secondary flocculation tank 7 are respectively equipped with a first frame reaction stirrer 17 and a second frame reaction stirrer 19.
[0045] A frame-type reactor is used to stir the flocculation tank, increasing the contact between the flocculant and the wastewater and improving the flocculation effect of the wastewater.
[0046] In this embodiment, a drain pipe 21 is provided on one side of the lower end of the secondary oxidation tank 5; the secondary oxidation tank 5.
[0047] In this embodiment, both the primary oxidation tank 1 and the secondary oxidation tank 5 are equipped with a bottom perforated pipe 15; the bottom perforated pipe 15 is connected to the air pipe 14; and the primary oxidation tank 1 is also connected to the RO concentrate pipe 13.
[0048] In this embodiment, both the primary sedimentation tank 4 and the secondary sedimentation tank 8 are equipped with honeycomb packing material 22, and a packing tube 23 is provided in the middle of the honeycomb packing material 22.
[0049] Adding filler material into the honeycomb filler 22 through the filler tube 23 facilitates wastewater treatment.
[0050] In this embodiment, a transition pool lift pump 20 is provided on one side of the transition pool 9, wherein the liquid inlet of the transition pool lift pump 20 is connected to the transition pool 9, and its liquid outlet is connected to the triple-effect evaporator 10.
[0051] In this embodiment, the perforated pipe 15 at the bottom of the pool has multiple perforations, with each pair of perforations angled at 45 degrees. This increases the aeration area and improves the oxidation treatment of wastewater.
[0052] The working principle of this utility model is as follows: the RO concentrate needs to go through a total of 8 stages in the pretreatment system, namely primary oxidation, primary coagulation, primary sedimentation, secondary oxidation, secondary coagulation, secondary sedimentation, water volume adjustment, and bag filtration.
[0053] The membrane concentrate is first pumped from the storage tank into the primary oxidation tank 1 via the RO concentrate pipeline 13 through the booster pump for advanced oxidation. After oxidation, it is transported to the primary mixing tank 2 for mixing. The concentrate will produce a lot of suspended sludge. Then, it is added to the primary flocculation tank (3) for flocculation and capture, and then discharged into the primary sedimentation tank (4) for settling and discharge. This process is called primary coagulation + primary sedimentation.
[0054] Then, after settling and removing particulate matter in the secondary mixing tank (6), secondary flocculation tank (7), and secondary sedimentation tank (8), the entire pretreatment process is completed. The concentrated liquid after pretreatment continues to enter the downstream transition tank (9), and then is pumped into the triple-effect evaporator (10) by the transition tank lift pump (20) for evaporation and volume reduction treatment.
[0055] After two stages of oxidation, coagulation, and sedimentation, the concentrated liquid enters the transition tank for water volume adjustment to meet the actual production needs of the subsequent triple-effect evaporation process. The concentrated liquid exiting the transition tank (with the addition of ammonium chloride to slow down scaling and increase evaporation rate) is further filtered by a bag filter to remove excess water and then oxidized in the secondary oxidation tank 5.
[0056] This pretreatment process is designed for the "concentrated liquid" produced after our leachate treatment. Its main purpose is to remove COD and calcium and magnesium ions from the wastewater. After the entire process, the COD content in the wastewater can be reduced by about 45%, and the hardness can be reduced by at least 50%, which can greatly slow down the scaling rate of the subsequent triple-effect evaporator and improve the evaporation efficiency.
[0057] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.
[0058] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style of the specification is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.
Claims
1. A novel pretreatment device for municipal solid waste leachate before membrane concentration and evaporation, characterized in that: It includes a primary oxidation tank (1), which is connected to a primary mixing tank (2); the primary mixing tank (2) is connected to a primary flocculation tank (3); the primary flocculation tank (3) is connected to a primary sedimentation tank (4); and the primary sedimentation tank (4) is connected to a secondary oxidation tank (5). The secondary oxidation tank (5) is connected to the secondary mixing tank (6); the secondary mixing tank (6) is connected to the secondary flocculation tank (7); the secondary flocculation tank (7) is connected to the secondary sedimentation tank (8); the secondary sedimentation tank (8) is connected to the transition tank (9).
2. The novel pretreatment device for municipal solid waste leachate membrane concentration and evaporation according to claim 1, characterized in that: The primary oxidation tank (1) is provided with an empty pipe (21) on one side of its lower end; the primary oxidation tank (1) is L-shaped and has three first partitions (11) inside, thereby forming four primary oxidation chambers; and each first partition (11) between two adjacent oxidation chambers has an overflow groove.
3. The novel pretreatment device for municipal solid waste leachate membrane concentration and evaporation according to claim 1, characterized in that: The primary mixing tank (2) and the secondary mixing tank (6) are respectively equipped with a first folding paddle mixer (16) and a second folding paddle mixer (18). The primary flocculation tank (3) and the secondary flocculation tank (7) are respectively equipped with a first frame reaction agitator (17) and a second frame reaction agitator (19).
4. The novel pretreatment device for municipal solid waste leachate membrane concentration and evaporation according to claim 1, characterized in that: The secondary oxidation tank (5) is provided with an empty pipe (21) on one side of its lower end; the secondary oxidation tank (5).
5. The novel pretreatment device for municipal solid waste leachate membrane concentration and evaporation according to claim 4, characterized in that: The secondary oxidation tank (5) is L-shaped and has three second partitions (12) inside, thus forming four secondary oxidation chambers; and each second partition (12) between two adjacent oxidation chambers has an overflow groove.
6. The novel pretreatment device for municipal solid waste leachate membrane concentration and evaporation according to claim 1, characterized in that: The primary oxidation tank (1) and the secondary oxidation tank (5) are both equipped with bottom perforated pipes (15); the bottom perforated pipes (15) are connected to the air pipe (14); the primary oxidation tank (1) is also connected to the RO concentrate pipe (13).
7. The novel pretreatment device for municipal solid waste leachate membrane concentration and evaporation according to claim 1, characterized in that: Both the primary sedimentation tank (4) and the secondary sedimentation tank (8) are equipped with honeycomb packing material (22), and a packing pipe (23) is provided in the middle of the honeycomb packing material (22).
8. The novel pretreatment device for municipal solid waste leachate membrane concentration and evaporation according to claim 1, characterized in that: A transition pool lift pump (20) is provided on one side of the transition pool (9), wherein the liquid inlet of the transition pool lift pump (20) is connected to the transition pool (9), and its liquid outlet is connected to the triple-effect evaporator (10).
9. The novel pretreatment device for municipal solid waste leachate membrane concentration and evaporation according to claim 6, characterized in that: The perforated pipe (15) at the bottom of the pool has multiple perforations, and each pair of perforations is inclined at 45 degrees.