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CN-116639841-B - Full-quantization separation treatment system and method for leachate of landfill

CN116639841BCN 116639841 BCN116639841 BCN 116639841BCN-116639841-B

Abstract

The application discloses a full-quantization separation treatment system and method for leachate in a landfill, wherein the system comprises a DTRO system, a seed crystal pretreatment system, a sludge press filtration system, a material separation membrane system, an evaporation system, a secondary RO system, a mother liquor solidification system and an electrocatalytic oxidation system. The main process of DTRO+material membrane+electrocatalytic oxidation+evaporator is adopted, so that the total emission up to standard can be realized, and the method is particularly aimed at ammonia nitrogen and total nitrogen. The system of the application is a purely materialized process, has high stability, small occupied area and low equipment energy consumption.

Inventors

  • Chi Junyong
  • LI FANGYUE
  • XIE JUNYING
  • CHEN CHEN

Assignees

  • 江苏坤奕环境技术股份有限公司

Dates

Publication Date
20260512
Application Date
20230615

Claims (17)

  1. 1. A full-quantization separation treatment system for leachate in a landfill is characterized by comprising a DTRO system, a seed crystal pretreatment system, a sludge press filtration system, a material separation membrane system, an evaporation system, a secondary RO system, a mother liquor solidification system and an electrocatalytic oxidation system; The dense water outlet of the DTRO system is connected with the seed crystal pretreatment system, the water outlet of the DTRO system is connected with the secondary RO system, the mud water mixture outlet of the seed crystal pretreatment system is connected with the mud filter pressing system, the water outlet of the seed crystal pretreatment system is connected with the material separation membrane system, the dense water outlet of the material separation membrane system is connected with the evaporation system, the water outlet of the material separation membrane system is connected with the electrocatalytic oxidation system, the water outlet of the evaporation system is connected with the secondary RO system, the mother liquor outlet of the evaporation system is connected with the mother liquor solidification system, and the dense water outlet of the secondary RO system is connected with the electrocatalytic oxidation system; the DTRO system comprises a high-pressure plunger type water inlet pump, a circulating booster pump and a disc-tube type DTRO membrane assembly; The DTRO system has an open flow path and a turbulent flow design.
  2. 2. The landfill leachate full quantification separation treatment system according to claim 1, wherein, The seed crystal pretreatment system comprises a dosing unit, a hovering unit, a precipitation unit, an aeration unit and a multi-medium filter unit.
  3. 3. The landfill leachate full-quantization separation treatment system according to claim 1, wherein the anode of the electrocatalytic oxidation system is one or a combination of a plurality of titanium-based ruthenium-iridium-tantalum-tin coated plates, titanium-based ruthenium-iridium-tantalum coated plates and titanium-based ruthenium-iridium coated plates, and the cathode is one or a combination of a plurality of 304 stainless steel plates, 316L stainless steel plates, 2205 duplex stainless steel plates, 2507 duplex stainless steel plates and titanium plates.
  4. 4. A landfill leachate full quantification separation treatment system according to claim 3, wherein the distance between the anode and the cathode is 10-20mm, and the running current density is 200-500A/m 2 .
  5. 5. The landfill leachate full quantification separation treatment system of claim 1, wherein the evaporation system comprises a primary evaporation and a secondary evaporation.
  6. 6. The landfill leachate full-quantization separation treatment system according to claim 5, wherein the first-stage evaporation is falling film evaporation, and the second-stage evaporation is negative pressure forced circulation MVR.
  7. 7. The landfill leachate full quantification separation treatment system according to claim 2, wherein the dosing unit contains a medicament.
  8. 8. The landfill leachate full quantification separation treatment system of claim 7, wherein the medicament comprises calcium sulfate seed crystal, calcium carbonate seed crystal, calcium hydroxide, sodium hydroxide and sodium carbonate.
  9. 9. A method for the total quantitative separation of leachate in a landfill using the total quantitative separation treatment system of any one of claims 1 to 8, comprising: delivering landfill leachate into the DTRO system for concentration treatment to obtain first produced water and first concentrated water; the first concentrated water is sent into the seed crystal pretreatment system, is mixed with the medicament of the dosing unit in the suspending unit and is suspended, and enters the precipitation unit to be separated to obtain settled mud and liquid after full reaction; sending the second produced water into the material separation membrane system to obtain third produced water and second concentrated water; sending the second concentrated water into the evaporation system to obtain mother liquor and fourth produced water; sending the mother liquor into a mother liquor solidification system; mixing the first produced water with the fourth produced water, feeding the mixed water into the second-stage RO system to obtain fifth produced water and third concentrated water, and And mixing the third concentrated water with the third produced water, and sending the mixture into the electrocatalytic oxidation system to obtain sixth produced water and fifth produced water, and discharging the sixth produced water and the fifth produced water.
  10. 10. The method according to claim 9, wherein the chemical comprises calcium sulfate seed, calcium carbonate seed, calcium hydroxide, sodium hydroxide and sodium carbonate.
  11. 11. The full-scale separation treatment method according to claim 10, wherein the adding amount of the calcium sulfate seed crystal is 50-100 mg/L, the adding amount of the calcium carbonate seed crystal is 50-100 mg/L, the adding amount of the sodium carbonate is 2-5 g/L, and the adding amount of the sodium hydroxide is used for adjusting the pH of the first concentrated water to 11.2-11.5.
  12. 12. The full-scale separation treatment method according to claim 10, wherein the mass ratio of the dosage of the calcium hydroxide to the bicarbonate in the first concentrated water is 1-0.8:1.
  13. 13. The full-scale separation treatment method according to claim 10, wherein the chemical further comprises PAM 1 to 5mg/L.
  14. 14. The full-quantization separation processing method according to claim 9, wherein the mixed hover time of the first concentrated water and the chemical in the hover unit is 10-20 min; the rising flow rate of the first concentrated water in the precipitation unit is 3-5 m/h; the air-water ratio of the aeration unit is 5-10:1, and the residence time is 30-60 min.
  15. 15. The full-scale separation treatment method according to claim 9, wherein the operating pressure of the material separation membrane system is 0.5 to 1.5MPa.
  16. 16. The full-scale separation processing method according to claim 9, wherein a curing agent is added to the mother liquor curing system.
  17. 17. The full-quantitative separation treatment method according to claim 16, wherein the curing agent component comprises, by weight, 0.15-0.20 part of a heavy metal stabilizer component, 0.10-0.17 part of a thickener component, 0.008-0.05 part of an alkaline activator component and 0.08-0.10 part of a strengthening curing agent.

Description

Full-quantization separation treatment system and method for leachate of landfill Technical Field The application relates to the technical field of sewage treatment, in particular to a full-quantization separation treatment system and method for leachate in a landfill. Background Landfill leachate is a black or tan liquid with malodorous smell. The percolate contains a large amount of organic matters and inorganic matters, including various aromatic compounds, humus and other refractory organic matters, such as ammonia, carbonate, sulfate and other inorganic salts. Because of the complex components in the garbage, the biggest characteristic of the garbage leachate water quality is that the pollutant content is very high and the toxicity is stronger. Wherein the highest mass concentration of COD can reach more than 15000mg/L, benzene and various derivatives thereof are contained, and the mass concentration of ammonia nitrogen can reach 7000mg/L. The wastewater containing toxic organic matters and high ammonia nitrogen brings great difficulty to the treatment, especially biological treatment. In addition to toxic aromatic compounds, percolate also contains a large amount of macromolecular organic substances such as humus and humic acid. Although the organic matters have no biotoxicity, the organic matters have high molecular weight and good chemical stability, and microorganisms cannot be effectively degraded, so that the COD of the percolate is difficult to effectively remove by the traditional biochemical treatment method. In recent years, most old landfill sites perform a great deal of reduction engineering on landfill leachate, the reduction engineering almost adopts a disc-tube reverse osmosis technology (DTRO), and a great deal of membrane concentrate produced by the engineering is refilled to cause a great deal of organic pollutants and inorganic salts to be continuously enriched, so that the quality of the landfill leachate is further deteriorated, the conductivity is often more than 50mS/cm, and a biochemical system is crashed and cannot operate. Even though the current mainstream technology of full-quantization treatment of the landfill leachate of a membrane system and an evaporation system still mostly has the reflux of ammonia nitrogen and low-boiling-point VOCs, the continuous enrichment causes the problem that the produced water does not reach the standard after long-time operation, and in addition, the current technology of full-quantization treatment of the landfill leachate still has the problem of excessively high energy consumption. Disclosure of Invention In order to solve the above-mentioned shortcomings in the art, the present application aims to provide a landfill leachate full-quantization separation treatment system and method. According to one aspect of the application, a full-quantification separation treatment system for leachate in a landfill is provided, which is characterized by comprising a DTRO system, a seed crystal pretreatment system, a sludge press filtration system, a material separation membrane system, an evaporation system, a secondary RO system, a mother liquor solidification system and an electrocatalytic oxidation system; The system comprises a seed crystal pretreatment system, a material separation membrane system, an evaporation system, a mother liquor solidification system, a secondary RO system, a sludge press filtration system, a material separation membrane system, an evaporation system and a mother liquor solidification system, wherein the DTRO system is respectively connected with the seed crystal pretreatment system and the secondary RO system; the seed crystal pretreatment system comprises a dosing unit, a hovering unit, a precipitation unit, an aeration unit and a multi-medium filter unit. According to some embodiments of the application, the DTRO system comprises a high pressure plunger type water inlet pump, a circulating booster pump and a disc tube type DTRO membrane assembly. According to some embodiments of the application, the anode of the electrocatalytic oxidation system is one or a combination of a plurality of titanium-based ruthenium-iridium-tantalum-tin coated electrode plates, titanium-based ruthenium-iridium-tantalum coated electrode plates and titanium-based ruthenium-iridium coated electrode plates, and the cathode is one or a combination of a plurality of 304 stainless steel electrode plates, 316L stainless steel electrode plates, 2205 duplex stainless steel electrode plates, 2507 duplex stainless steel electrode plates and titanium electrode plates; According to some embodiments of the application, the anode and the cathode are spaced apart by 10-20mm and the operating current density is 200-500A/m2. According to some embodiments of the application, the evaporation system comprises a primary evaporation and a secondary evaporation; According to some embodiments of the application, the first-stage evaporation is falling film evaporation