CN110615501B - Method for treating landfill leachate - Google Patents

Method for treating landfill leachate Download PDF

Info

Publication number
CN110615501B
CN110615501B CN201910915915.8A CN201910915915A CN110615501B CN 110615501 B CN110615501 B CN 110615501B CN 201910915915 A CN201910915915 A CN 201910915915A CN 110615501 B CN110615501 B CN 110615501B
Authority
CN
China
Prior art keywords
leachate
sulfate
doped
landfill leachate
ammonia nitrogen
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201910915915.8A
Other languages
Chinese (zh)
Other versions
CN110615501A (en
Inventor
黄涛
宋东平
张树文
周璐璐
陶骏骏
徐娇娇
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang Huike Environmental Protection Technology Co ltd
Original Assignee
Changshu Institute of Technology
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Changshu Institute of Technology filed Critical Changshu Institute of Technology
Priority to CN201910915915.8A priority Critical patent/CN110615501B/en
Publication of CN110615501A publication Critical patent/CN110615501A/en
Application granted granted Critical
Publication of CN110615501B publication Critical patent/CN110615501B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/30—Treatment of water, waste water, or sewage by irradiation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/46104—Devices therefor; Their operating or servicing
    • C02F1/46109—Electrodes
    • C02F1/46114—Electrodes in particulate form or with conductive and/or non conductive particles between them
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/467—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction
    • C02F1/4672—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction by electrooxydation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/467—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction
    • C02F1/4672—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction by electrooxydation
    • C02F1/4674—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis by electrochemical disinfection; by electrooxydation or by electroreduction by electrooxydation with halogen or compound of halogens, e.g. chlorine, bromine
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/72—Treatment of water, waste water, or sewage by oxidation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/46—Treatment of water, waste water, or sewage by electrochemical methods
    • C02F1/461—Treatment of water, waste water, or sewage by electrochemical methods by electrolysis
    • C02F1/46104—Devices therefor; Their operating or servicing
    • C02F1/46109—Electrodes
    • C02F2001/46133—Electrodes characterised by the material
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/16—Nitrogen compounds, e.g. ammonia
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/20—Heavy metals or heavy metal compounds
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/20—Heavy metals or heavy metal compounds
    • C02F2101/22—Chromium or chromium compounds, e.g. chromates
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
    • C02F2103/06—Contaminated groundwater or leachate
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2305/00—Use of specific compounds during water treatment
    • C02F2305/02—Specific form of oxidant
    • C02F2305/023—Reactive oxygen species, singlet oxygen, OH radical
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2305/00—Use of specific compounds during water treatment
    • C02F2305/10—Photocatalysts

Landscapes

  • Chemical & Material Sciences (AREA)
  • Water Supply & Treatment (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Hydrology & Water Resources (AREA)
  • Engineering & Computer Science (AREA)
  • Environmental & Geological Engineering (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Physical Water Treatments (AREA)
  • Water Treatment By Electricity Or Magnetism (AREA)

Abstract

The invention discloses a method for treating landfill leachate, which comprises the steps of weighing ferrous sulfate, dissolving the ferrous sulfate in the landfill leachate to obtain sulfate-doped leachate; weighing g-C3N4adding/PDI @ MOF into the sulfate doped leachate, uniformly stirring to obtain a particle electrode mixed leachate, and adjusting the pH value to acidity by using dilute sulfuric acid and sodium hydroxide; adding the particle electrode mixed leachate into a three-dimensional electrode reactor, carrying out an electrolytic reaction on the particle electrode mixed leachate under the irradiation of visible light while stirring, standing for precipitation, and carrying out solid-liquid separation to obtain the treated landfill leachate. The invention can realize the synchronous and high-efficiency removal of COD, ammonia nitrogen and various heavy metal ions in the landfill leachate; the removal rate of COD, ammonia nitrogen and heavy metal ions by the three-dimensional photoelectrocatalysis oxidation technology is obviously higher than the sum of the removal rates of the pure electrocatalysis oxidation technology, the photocatalysis oxidation technology and the two technologies; the invention has simple removing process and low cost.

Description

Method for treating landfill leachate
Technical Field
The invention relates to a method for treating landfill leachate, in particular to a method for treating landfill leachate by using a three-dimensional photoelectrocatalysis oxidation technology.
Background
The landfill leachate is a filtrate generated by spontaneous fermentation of garbage under anaerobic conditions in the landfill process. Generally, landfill leachate contains high-concentration organic pollutants, ammonia nitrogen, inorganic salts and heavy metals. The landfill leachate can not only spread diseases and directly harm human health, but also pollute surface water and cause irreversible damage to the original ecological environment of surrounding soil.
The current treatment technology for landfill leachate mainly comprises the following steps: physical chemical treatment technology, biological treatment technology and membrane treatment technology. The physical and chemical treatment technology mainly comprises the following steps: leachate concentration, stripping, activated carbon adsorption, ion exchange, advanced oxidation and the like, but the physicochemical treatment technology has the problems of single treatment target, high treatment cost, complex treatment process and the like. Although the methods can achieve high removal rate of a certain index in the leachate in a short time, the method is difficult to ensure that the indexes of ammonia nitrogen, organic pollutants, heavy metals and the like are efficiently removed at the same time. Moreover, the application of the physical and chemical treatment technology to treat the landfill leachate also causes other problems to be solved, for example, the concentrated solution generated by the leachate concentration technology still needs to be deeply treated; the stripping and activated carbon adsorption technology only transfers ammonia nitrogen from leachate to activated carbon, so that not only the treated waste liquid needs to be treated, but also the newly generated activated carbon waste needs to be treated; because the oxidant used in the advanced oxidation technology is generally toxic to human bodies, needs supporting safety guarantee and has high dependence on the dosage and performance of the oxidant, the problem of secondary pollution is easily caused in the disposal process, and serious safety accidents can be caused by misoperation of workers. The biological treatment technology is divided into an aerobic process, an anaerobic process and an anaerobic and aerobic combined process according to different process principles, and for the biological treatment technology, the problems of large process floor area, long process operation period, poor process removal effect, high process environment sensitivity and the like exist no matter which process is applied to treat the landfill leachate. The membrane treatment technology is divided into 4 types of microfiltration, ultrafiltration, nanofiltration and reverse osmosis according to the pore size of the material. The treatment of the landfill leachate by using the membrane method treatment technology has the problems of easy blockage of membrane pores, easy loss of membrane materials, unstable treatment working conditions and the like, and the residual waste membrane materials and leachate concentrated solution after the treatment of the leachate still need to be further treated.
Therefore, the existing treatment technology generally has the problems of complex treatment process, high treatment cost, single treatment target, further advanced treatment of the treated percolate and the like.
Disclosure of Invention
The purpose of the invention is as follows: aiming at the problems, the invention provides a method for treating landfill leachate by using a three-dimensional photoelectrocatalysis technology, which has simple treatment process and can realize the high-efficiency synchronous removal of organic pollutants, ammonia nitrogen and various heavy metal ions in the leachate.
The technical scheme is as follows: the invention relates to a method for treating landfill leachate, which comprises the steps of weighing ferrous sulfate, dissolving the ferrous sulfate in the landfill leachate to obtain sulfate-doped leachate; weighing g-C3N4adding/PDI @ MOF into the sulfate doped leachate, uniformly stirring to obtain a particle electrode mixed leachate, and adjusting the pH value to acidity by using dilute sulfuric acid and sodium hydroxide; adding the particle electrode mixed leachate into a three-dimensional electrode reactor, carrying out an electrolytic reaction on the particle electrode mixed leachate under the irradiation of visible light while stirring, standing for precipitation, and carrying out solid-liquid separation to obtain the treated landfill leachate.
Furthermore, the concentration of ferrous sulfate in the sulfate-doped leachate is 0.045-0.175 mol/L, the comprehensive removal effect and cost are further preferably 0.05-0.15 mol/L, and the concentration can be 0.05mol/L, 0.1mol/L or 0.15 mol/L.
Further, said g-C3N4The solid-liquid ratio of the/PDI @ MOF to the sulfate doped leachate is 0.0018-0.02: 1, the comprehensive removal effect and the cost are further preferably 0.002-0.01: 1, and the ratio can be 0.002:1, 0.006:1 or 0.01: 1.
Further, the voltage gradient of the electrolytic reaction is 0.35-1.75V/cm, the comprehensive removal effect and the cost are further preferably 0.5-1.5V/cm, and the comprehensive removal effect and the cost can be 0.5V/cm, 1V/cm or 1.5V/cm.
Further, the pH value of the particle electrode mixed leachate is adjusted to 2-4.
Furthermore, the time of the electrolytic reaction is 2-6 h, and the stirring speed is 30-120 rpm.
Adding the granular electrode mixed leachate into an electrolytic cell sample area of a three-dimensional electrode reactor, and after switching on direct current, mixing g-C in the leachate3N4the/PDI @ MO particles are polarized and converted to particle electrodes. Water molecules are hydrolyzed at the cathode of the particle electrode to generate hydroxide ions and hydrogen gas, and are hydrolyzed at the anode of the particle electrode to generate hydrogen ions and oxygen gas. At the same time, under the irradiation of visible light, g-C3N4the/PDI @ MOF particle electrode generates photocatalysis to generate a photoproduction hole and a photoproduction electron. The photo-generated electrons react with oxygen on the surface of the particle electrode and oxygen in the leachate to generate oxygen radicals, and the oxygen radicals further react with hydrogen ions to generate hydrogen peroxide molecules. The hydrogen peroxide molecules react with ferrous ions on the surface of the particle electrode and ferrous ions doped in the leachate to generate hydroxyl radicals. Meanwhile, the photoproduction cavity can directly oxidize water molecules to generate hydroxyl radicals; photogenerated holes can also directly oxidize and decompose part of the organic pollutants. The hydroxyl radicals can effectively degrade organic matters in the leachate to generate hydroxyl ions, carbon dioxide and water. Meanwhile, the hydroxyl radical can react with chloride ions in the leachate to generate a chloride ion radical, and the chloride ion radical can react with ammonia nitrogen to generate chloride ions and nitrogen. The generated ferric ions can obtain electrons at the particle electrode and the cathode of the main electrode of the electrolytic cell and are reduced into ferrous ions again. Hydroxyl ions generated on the surfaces of the particle electrode and the cathode of the main electrode of the electrolytic cell and hydroxyl ions generated by the redox reaction in the leachate react with divalent heavy metal ions in the leachate to generate hydroxyl precipitates. And the hexavalent chromium ions firstly react with carbon dioxide free radicals generated in the indirect process of the organic pollutants to generate trivalent chromium. The trivalent chromium reacts with the hydroxide ions to produce hydroxide precipitate. Meanwhile, due to the electromigration effect and the electroosmotic flow effect, part of the divalent heavy metal ions and trivalent chromium ions are transferred to the electrolytic bath Main electrode the cathode electrode surface and subsequently reacts with hydroxide ions at the electrode surface. Part of ammonia nitrogen is transferred to the surface of the main electrode anode by electromigration and is oxidized into nitrogen. Organic pollutants with different polarities are migrated to the surface of a main electrode (including an anode and a cathode) through electroosmotic flow, and pre-oxidation and pre-reduction decomposition are realized. The pre-decomposition step is beneficial to improving the degradation efficiency of hydroxyl radicals to organic matters.
Has the advantages that: compared with the prior art, the invention has the following remarkable advantages: (1) the invention can realize the synchronous and high-efficiency removal of COD, ammonia nitrogen and various heavy metal ions of zinc, copper, cadmium and chromium in the landfill leachate, and the removal rates of the COD, the ammonia nitrogen and the zinc, the copper, the cadmium and the chromium are respectively as high as 98%, 92% and 95%; (2) the removal rate of COD, ammonia nitrogen and heavy metal ions by the three-dimensional photoelectrocatalysis oxidation technology is obviously higher than the sum of the removal rates of the pure electrocatalysis oxidation technology, the photocatalysis oxidation technology and the two technologies; (3) the invention has simple removal process and low cost, and can not generate other problems to be further solved after treatment.
Drawings
FIG. 1 is a flow chart of the present invention.
Detailed Description
The invention is further described below with reference to the figures and examples.
It should be noted that the landfill leachate of the present invention is obtained from sanitary landfill of domestic garbage in Qingcheng mountain of Haizhou area, Lingyun harbor. The mass concentration of COD in the landfill leachate is 1205mg/L, the concentration of ammonia nitrogen is 757mg/L, and the heavy metal ions (Zn) contained in the landfill leachate are 34mg/L zinc ions2+) 15mg/L of copper ion (Cu)2+) 7mg/L of lead ion (Pb)2+) 21mg/L cadmium ion (Cd)2+) And 58mg/L total chromium (including hexavalent chromium and trivalent chromium ions).
g-C3N4Synthesis of/PDI @ MOF reference Construction of g-C3N4[ the term "/PDI @ MOF heterojunctions for the high effective light-driven definition of pharmaceutical and phenolic micropollutants", which is not described herein in detail.
For the construction of the three-dimensional electrode reactor, reference is made to "Operating optimization for the maintenance metal removal from the mechanical solid contacting flash in the three-dimensional electrochemical devices", which is not described herein again.
Example 1
Influence of ferrous sulfate concentration on removal rate of COD, ammonia nitrogen and heavy metal ions in landfill leachate
And (3) treating the landfill leachate: as shown in fig. 1, ferrous sulfate is weighed and dissolved in the landfill leachate to obtain sulfate-doped leachate, wherein the concentrations of the ferrous sulfate are respectively 0.025mol/L, 0.035mol/L, 0.045mol/L, 0.05mol/L, 0.1mol/L, 0.15mol/L, 0.155mol/L, 0.165mol/L and 0.175 mol/L; g-C is weighed according to the solid-to-liquid ratio of 0.002:1(g: mL) 3N4Mixing the/PDI @ MOF powder into the sulfate doped leachate, and uniformly stirring to obtain a granular electrode mixed leachate; adjusting the pH of the particle electrode mixed leachate by using dilute sulfuric acid and sodium hydroxide to ensure that the pH of the particle electrode mixed leachate is equal to 2; then pouring the granular electrode mixed leachate into an electrolytic cell sample area of a three-dimensional electrode reactor, and switching on a direct current power supply, wherein the voltage gradient is 0.5V/cm; and in the electrifying process, turning on a xenon lamp to carry out visible light irradiation on the particle electrode mixed leachate in the sample area, continuously stirring the particle electrode mixed leachate at the stirring speed of 30rpm for 2 hours, standing for precipitation, and carrying out solid-liquid separation to obtain the treated landfill leachate.
COD concentration detection and COD removal rate calculation: the concentration of Chemical Oxygen Demand (COD) in the landfill leachate is measured according to the national standard bichromate method for measuring water quality chemical oxygen demand (GB 11914-; the COD removal rate was calculated according to the formula (1), wherein RCODAs the removal rate of COD, c0And ctThe COD concentration (mg/L) of the landfill leachate before and after treatment is respectively shown.
Figure BDA0002216106060000041
Detecting the ammonia nitrogen concentration and calculating the ammonia nitrogen removal rate: the concentration of ammonia nitrogen in landfill leachate is measured according to the specification of ammonia nitrogen in water quality Measuring by quantitative salicylic acid spectrophotometry (HJ 536-2009); the ammonia nitrogen removal rate is calculated according to the formula (2), wherein RNFor ammonia nitrogen removal, cN0The initial concentration (mg/L) of ammonia nitrogen in the landfill leachate before treatment, cNtThe residual ammonia nitrogen concentration (mg/L) in the treated landfill leachate is adopted.
Figure BDA0002216106060000042
Detecting the concentration of the heavy metal ions and calculating the removal rate: the concentration of four heavy metal ions of zinc, copper, lead and cadmium in the landfill leachate is measured according to the method for measuring 32 elements in water quality by inductively coupled plasma emission spectrometry (HJ 776-2015), and the concentration of total chromium is measured according to the method for measuring flame atomic absorption spectrophotometry (HJ 757-2015) for water quality chromium; the removal rate of heavy metal M ions (M: Zn, Cu, Pb, Cd, Cr) is calculated according to the formula (3), wherein RMFor heavy metal ion removal rate, cM0Is the initial concentration (mg/L), c of heavy metal M ions in the landfill leachate before treatmentMtThe concentration (mg/L) of heavy metal M ions in the treated landfill leachate is shown.
Figure BDA0002216106060000043
The test results of the removal rate of COD, ammonia nitrogen and heavy metal ions in the landfill leachate are shown in table 1.
TABLE 1 influence of ferrous sulfate concentration on removal rate of COD, ammonia nitrogen and heavy metal ions in landfill leachate
Figure BDA0002216106060000044
As can be seen from Table 1, the removal rate of heavy metal ions is greater than 85%, and the change of the concentration of ferrous sulfate has no significant influence on the removal rate of heavy metal ions in the leachate. For the removal rate of COD and ammonia nitrogen in leachate, when the concentration of ferrous sulfate is less than 0.05mol/L (as in table 1, when the concentration of ferrous sulfate is 0.045, 0.035, 0.025mol/L and lower values not listed in table 1), the divalent iron ions react with hydrogen peroxide molecules to generate less hydroxyl radicals, so that the degradation of organic pollutants is insufficient and the oxidation efficiency of ammonia nitrogen is reduced, resulting in that the removal rate of COD is less than 79% and is significantly reduced with the reduction of the concentration of ferrous sulfate, resulting in that the removal rate of ammonia nitrogen is less than 72% and is significantly reduced with the reduction of the concentration of ferrous sulfate. When the concentration of the ferrous sulfate is equal to 0.05-0.15 mol/L (as shown in Table 1, when the concentration of the externally-doped ferrous sulfate is equal to 0.05, 0.10 and 0.15 mol/L), the externally-doped ferrous ions in the filtrate fully react with hydrogen peroxide molecules to generate a large amount of hydroxyl radicals, the hydroxyl radicals can effectively degrade organic matters in the leachate to generate hydroxyl ions, carbon dioxide and water, meanwhile, the hydroxyl ions can react with chloride ions in the leachate to generate chloride ion radicals, the chloride ion radicals can react with ammonia nitrogen to generate chloride ions and nitrogen, finally, the removal rate of COD is larger than 84%, and the removal rate of ammonia nitrogen is larger than 76%. When the ferrous sulfate concentration is greater than 0.15mol/L (as in table 1, the doped ferrous sulfate concentration is 0.155, 0.165, 0.175mol/L and higher values not listed in table 1), the change in ferrous sulfate concentration has no significant effect on COD removal rate and ammonia nitrogen removal rate. Therefore, in a comprehensive aspect, the benefit and the cost are combined, and when the concentration of the ferrous sulfate is equal to 0.05-0.15 mol/L, the removal rate of COD, ammonia nitrogen and heavy metal ions in the landfill leachate is improved most favorably.
Example 2
C3N4Influence of solid-liquid ratio of/PDI @ MOF and sulfate doped leachate on removal rate of COD, ammonia nitrogen and heavy metal ions in landfill leachate
And (3) treating the landfill leachate: weighing ferrous sulfate, and dissolving the ferrous sulfate into the landfill leachate to obtain sulfate-doped leachate, wherein the concentration of the ferrous sulfate is 0.15 mol/L; g-C is weighed according to the solid-to-liquid ratio of 0.001:1, 0.0015:1, 0.0018:1, 0.002:1, 0.006:1, 0.01:1, 0.012:1, 0.015:1 and 0.02:1(g: mL)3N4Mixing the/PDI @ MOF powder into the sulfate doped leachate, and uniformly stirring to obtain a granular electrode mixed leachate; the pH value of the mixed leachate of the particle electrode is adjusted by using dilute sulphuric acid and sodium hydroxide to ensure that the particles are chargedThe pH of the extremely mixed percolate is equal to 3; then pouring the granular electrode mixed leachate into an electrolytic cell sample area, and switching on a direct current power supply, wherein the voltage gradient is 1V/cm; and in the electrifying process, turning on a xenon lamp to carry out visible light irradiation on the particle electrode mixed leachate in the sample area, continuously stirring the particle electrode mixed leachate at the stirring speed of 75rpm for 4 hours, standing for precipitation, and carrying out solid-liquid separation to obtain the treated landfill leachate.
The COD concentration detection and the calculation of the COD removal rate, the ammonia nitrogen concentration detection and the calculation of the ammonia nitrogen removal rate, the heavy metal ion concentration detection and the calculation of the removal rate are the same as those in the example 1, and the test results are shown in the table 2.
TABLE 2C3N4Influence of solid-liquid ratio of/PDI @ MOF and sulfate doped leachate on removal rate of COD, ammonia nitrogen and heavy metal ions in landfill leachate
Figure BDA0002216106060000061
As can be seen from Table 2, when C is3N4The solid-to-liquid ratio of/PDI @ MOF to sulfate-doped leachate was less than 0.002:1(g: mL) (see Table 2, C3N4(PDI) @ MOF to sulfate-doped leachate at solid-to-liquid ratios of 0.0015, 0.0018, 0.001:1(g: mL) and lower ratios not listed in table 2), g-C under visible light irradiation3N4the/PDI @ MOF particle electrode generates less photoproduction holes and photoproduction electrons through photocatalysis, and then the generation amount of hydroxyl radicals and hydroxyl ions is reduced, so that the COD removal rate is less than 85%, and the COD removal rate is increased along with C3N4The solid-to-liquid ratio of the/PDI @ MOF to the sulfate doped leachate is reduced and remarkably reduced, so that the ammonia nitrogen removal rate is lower than 76 percent and the ammonia nitrogen removal rate is changed along with the C3N4The solid-liquid ratio of the/PDI @ MOF to the sulfate doped leachate is reduced and obviously reduced, so that the removal rate of heavy metal ions is lower than 83 percent and is along with C3N4The solid-to-liquid ratio of the/PDI @ MOF to the sulfate doped leachate is reduced and remarkably reduced. When C is present3N4The solid-to-liquid ratio of the/PDI @ MOF to the sulfate-doped leachate is equal to 0.002-0.01: 1(g: mL) (as shown in Table 2, C3N4(PDI) @ MOF to sulfate-doped leachate at a solid-to-liquid ratio of 0.002:1, 0.006:1, 0.01:1(g: mL), under irradiation with visible light g-C 3N4the/PDI @ MOF particle electrode generates a large amount of photo-generated holes and photo-generated electrons through photocatalysis, so that the generation amount of hydroxyl radicals and hydroxyl ions is sufficient, the COD removal rate is higher than 90%, the ammonia nitrogen removal rate is higher than 81%, and the heavy metal ion removal rate is higher than 86%. When C is present3N4The solid-to-liquid ratio of/PDI @ MOF to sulfate-doped leachate was greater than 0.01:1(g: mL) (see Table 2, C3N4(ii) solid to liquid ratio of/PDI @ MOF to sulfate-doped leachate-0.012: 1, 0.015:1, 0.02:1(g: mL) and higher ratios not listed in Table 2), C3N4The solid-liquid ratio change of the/PDI @ MOF and the sulfate doped leachate has no obvious influence on the removal rate of COD, ammonia nitrogen and heavy metal ions. Thus, in summary, combining benefits and costs, when C3N4When the solid-to-liquid ratio of the/PDI @ MOF to the sulfate doped leachate is equal to 0.002-0.01: 1(g: mL), the removal rate of COD, ammonia nitrogen and heavy metal ions in the landfill leachate is improved.
Example 3
Influence of voltage gradient on removal rate of COD, ammonia nitrogen and heavy metal ions in landfill leachate
And (3) treating the landfill leachate: weighing ferrous sulfate, and dissolving the ferrous sulfate into the landfill leachate to obtain sulfate-doped leachate, wherein the concentration of the ferrous sulfate is 0.15 mol/L; g-C is weighed according to the solid-to-liquid ratio of 0.01:1(g: mL) 3N4Mixing the/PDI @ MOF powder into the sulfate doped leachate, and uniformly stirring to obtain a granular electrode mixed leachate; adjusting the pH of the particle electrode mixed leachate by using dilute sulfuric acid and sodium hydroxide to ensure that the pH of the particle electrode mixed leachate is equal to 4; then pouring the mixed leachate of the particle electrodes into a sample area of an electrolytic cell, and switching on a direct current power supply, wherein the voltage gradients are respectively 0.25V/cm, 0.35V/cm, 0.45V/cm, 0.5V/cm, 1V/cm, 1.5V/cm, 1.55V/cm, 1.65V/cm and 1.75V/cm; in the electrifying process, a xenon lamp is turned on to carry out visible light irradiation on the particle electrode mixed percolate in the sample area, the particle electrode mixed percolate is continuously stirred at the stirring speed of 120rpm for 6 hours, and the mixture is stood for precipitationAnd carrying out solid-liquid separation to obtain the treated landfill leachate.
The COD concentration detection and the calculation of the COD removal rate, the ammonia nitrogen concentration detection and the calculation of the ammonia nitrogen removal rate, the heavy metal ion concentration detection and the calculation of the removal rate are the same as those in the example 1, and the test results are shown in the table 3.
TABLE 3 influence of voltage gradient on removal rate of COD, ammonia nitrogen and heavy metal ions in landfill leachate
Figure BDA0002216106060000071
As can be seen from table 3, when the voltage gradient is less than 0.5V/cm (as in table 3, when the voltage gradient is 0.45V/cm, 0.35V/cm, 0.25V/cm and lower values not listed in table 3), the electromigration and the electroosmotic flow are weak, so that the deposition yield of heavy metal ions on the surface of the cathode of the main electrode is reduced, the oxidation efficiency of ammonia nitrogen on the surface of the anode of the main electrode is reduced, the pretreatment effect of organic pollutants is deteriorated, and finally, the COD removal rate is less than 91% and is significantly reduced with the reduction of the voltage gradient, the ammonia nitrogen removal rate is less than 82% and is significantly reduced with the reduction of the voltage gradient, and the heavy metal removal rate is less than 89% and is significantly reduced with the reduction of the voltage gradient. When the voltage gradient is equal to 0.5-1.5V/cm (as shown in table 3, the voltage gradient is equal to 0.5V/cm, 1V/cm, and 1.5V/cm), under the action of electromigration and electroosmotic flow, part of divalent heavy metal and trivalent chromium ions are migrated to the surface of a cathode electrode of a main electrode of an electrolytic cell and then react with hydroxyl ions on the surface of the electrode, part of ammonia nitrogen is transferred to the surface of an anode of the main electrode through electromigration and oxidized into nitrogen, organic pollutants with different polarities are migrated to the surface of the main electrode (including the anode and the cathode) through electroosmotic flow, pre-oxidation and pre-reduction decomposition are realized, and finally, the COD removal rate is greater than 95%, the ammonia nitrogen removal rate is greater than 86%, and the heavy metal removal rate is greater than 90%. When the voltage gradient is more than 1.5V/cm (as shown in the table 3, when the voltage gradient is 1.55V/cm, 1.65V/cm and 1.75V/cm and higher values which are not listed in the table 3), the effect of the change of the voltage gradient on the removal rate of COD, ammonia nitrogen and heavy metals is not obvious. Therefore, in comprehensive terms, the benefit and the cost are combined, and when the voltage gradient is equal to 0.5-1.5V/cm, the removal rate of COD, ammonia nitrogen and heavy metal ions in the landfill leachate is improved most beneficially.
Comparative example 1
Weighing ferrous sulfate, and dissolving the ferrous sulfate into the domestic garbage leachate to obtain sulfate doped leachate, wherein the concentration of the ferrous sulfate is 0.15 mol/L; adjusting the pH value of the sulfate-doped percolate by using dilute sulfuric acid and sodium hydroxide to ensure that the pH value of the sulfate-doped percolate is equal to 4; then pouring the sulfate-doped percolate into a sample area of an electrolytic cell, and switching on a direct current power supply, wherein the voltage gradient is 1.5V/cm; and in the electrifying process, continuously stirring the leachate at the stirring speed of 120rpm, electrifying for 6 hours, standing for precipitation, and carrying out solid-liquid separation to obtain the landfill leachate subjected to electrochemical oxidation treatment.
Comparative example 2
Weighing ferrous sulfate, and dissolving the ferrous sulfate into the landfill leachate to obtain sulfate-doped leachate, wherein the concentration of the ferrous sulfate is 0.15 mol/L; g-C is weighed according to the solid-to-liquid ratio of 0.01:1(g: mL)3N4Mixing the/PDI @ MOF powder into the sulfate doped leachate, and uniformly stirring to obtain a granular electrode mixed leachate; adjusting the pH of the particle electrode mixed leachate by using dilute sulfuric acid and sodium hydroxide to ensure that the pH of the particle electrode mixed leachate is equal to 4; and (3) turning on a xenon lamp to carry out visible light irradiation on the particle electrode mixed leachate in the sample area, irradiating for 6 hours, standing for precipitation, and carrying out solid-liquid separation to obtain the landfill leachate subjected to photocatalytic oxidation treatment.
Example 4
Weighing ferrous sulfate, and dissolving the ferrous sulfate into the landfill leachate to obtain sulfate-doped leachate, wherein the concentration of the ferrous sulfate is 0.15 mol/L; g-C is weighed according to the solid-to-liquid ratio of 0.01:1(g: mL)3N4Mixing the/PDI @ MOF powder into the sulfate doped leachate, and uniformly stirring to obtain a granular electrode mixed leachate; adjusting the pH of the particle electrode mixed leachate by using dilute sulfuric acid and sodium hydroxide to ensure that the pH of the particle electrode mixed leachate is equal to 4; then pouring the granular electrode mixed leachate into an electrolytic cell sample area of a three-dimensional electrode reactor, and switching on a direct current power supply, wherein the voltage gradient is 1.5V/cm; in the electrifying process, the xenon lamp is turned on to carry out particle electrode in the sample areaAnd irradiating the mixed leachate with visible light, continuously stirring the particle electrode mixed leachate at the stirring speed of 120rpm, electrifying for 6 hours, standing for precipitation, and performing solid-liquid separation to obtain the landfill leachate subjected to three-dimensional photoelectrocatalysis oxidation treatment.
The landfill leachate treated by the comparative example 1, the comparative example 2 and the example 4 is respectively subjected to COD concentration detection and COD removal rate calculation, ammonia nitrogen concentration detection and ammonia nitrogen removal rate calculation, and heavy metal concentration detection and removal rate calculation, and the test results are shown in Table 4.
TABLE 4 influence of different treatment methods on removal rate of COD, ammonia nitrogen and heavy metal ions in landfill leachate
Figure BDA0002216106060000091
From the results in table 4, compared with two treatment methods, namely electrochemical oxidation and photocatalytic oxidation, the three-dimensional photoelectrocatalysis oxidation technology adopted by the invention can realize high-efficiency removal of COD, ammonia nitrogen and heavy metal ions in the landfill leachate, and moreover, the removal rate of the invention is higher than the sum of the removal rates of the comparative example 1 and the comparative example 2. The three-dimensional photoelectrocatalysis technology applied by the invention is obviously superior to the method which only applies electric technology, photocatalysis technology and the addition of the electric technology and the photocatalysis technology.

Claims (6)

1. A method for treating landfill leachate is characterized in that ferrous sulfate is weighed and dissolved in the landfill leachate to obtain sulfate doped leachate; weighing g-C3N4adding/PDI @ MOF into the sulfate doped leachate, uniformly stirring to obtain a particle electrode mixed leachate, and adjusting the pH value to acidity by using dilute sulfuric acid and sodium hydroxide; adding the particle electrode mixed leachate into a three-dimensional electrode reactor, carrying out an electrolytic reaction on the particle electrode mixed leachate under the irradiation of visible light while stirring, standing for precipitation, and carrying out solid-liquid separation to obtain treated landfill leachate;
The concentration of ferrous sulfate in the sulfate-doped percolate is 0.045-0.175 mol/L;
the g to C3N4The solid-liquid ratio of the/PDI @ MOF to the sulfate doped leachate is 0.0018-0.02: 1;
the voltage gradient of the electrolytic reaction is 0.35-1.75V/cm.
2. The method for treating landfill leachate according to claim 1, wherein the concentration of ferrous sulfate in the sulfate-doped leachate is 0.05-0.15 mol/L.
3. The method for treating landfill leachate according to claim 1, wherein the g-C is selected from the group consisting of3N4The solid-liquid ratio of the/PDI @ MOF to the sulfate doped leachate is 0.002-0.01: 1.
4. The method for treating landfill leachate according to claim 1, wherein the voltage gradient of the electrolysis reaction is 0.5-1.5V/cm.
5. The method for treating landfill leachate according to claim 1, wherein the pH of the granular electrode mixed leachate is adjusted to 2-4.
6. The method for treating landfill leachate according to claim 1, wherein the time of the electrolytic reaction is 2 to 6 hours, and the stirring rate is 30 to 120 rpm.
CN201910915915.8A 2019-09-26 2019-09-26 Method for treating landfill leachate Active CN110615501B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910915915.8A CN110615501B (en) 2019-09-26 2019-09-26 Method for treating landfill leachate

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910915915.8A CN110615501B (en) 2019-09-26 2019-09-26 Method for treating landfill leachate

Publications (2)

Publication Number Publication Date
CN110615501A CN110615501A (en) 2019-12-27
CN110615501B true CN110615501B (en) 2022-02-11

Family

ID=68924119

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910915915.8A Active CN110615501B (en) 2019-09-26 2019-09-26 Method for treating landfill leachate

Country Status (1)

Country Link
CN (1) CN110615501B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111087050A (en) * 2020-01-10 2020-05-01 江苏理工学院 Preparation of granule electrode and three-dimensional electrolytic reactor structure of optimization
CN111872027B (en) * 2020-07-16 2021-09-07 常熟理工学院 Method for co-processing waste incineration fly ash and printing and dyeing waste liquid

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102070230A (en) * 2010-12-10 2011-05-25 华中师范大学 Method for removing organic matters in water by utilizing three-dimensional electrode electro-fenton and device thereof
EP2784031A1 (en) * 2013-03-25 2014-10-01 Efacec Engenharia E Sistemas, S.A. Method of treating leachate, phototreatment reactors and respective use
WO2015040638A1 (en) * 2013-09-19 2015-03-26 Council Of Scientific & Industrial Research N-doped porous carbon electrocatalyst and process for preparation thereof
CN106927556A (en) * 2017-03-28 2017-07-07 天津泰达环保有限公司 A kind of method of electrolysis advanced treatment of landfill leachate
CN109012607A (en) * 2018-08-10 2018-12-18 南通寰宇博新化工环保科技有限公司 A kind of nanocomposite and preparation method thereof
CN109046425A (en) * 2018-08-13 2018-12-21 山东交通学院 Composite photo-catalyst TiO derived from a kind of MOF base2/g-C3N4Preparation method
CN109126893A (en) * 2018-10-09 2019-01-04 华东师范大学 A kind of oxidation of coal titanium-metal organic frame composite material and preparation method and application
CN109395777A (en) * 2018-04-12 2019-03-01 常州大学 A kind of Three-element composite photocatalyst BiOI@UIO-66 (NH2)@g-C3N4Preparation method

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102070230A (en) * 2010-12-10 2011-05-25 华中师范大学 Method for removing organic matters in water by utilizing three-dimensional electrode electro-fenton and device thereof
EP2784031A1 (en) * 2013-03-25 2014-10-01 Efacec Engenharia E Sistemas, S.A. Method of treating leachate, phototreatment reactors and respective use
WO2015040638A1 (en) * 2013-09-19 2015-03-26 Council Of Scientific & Industrial Research N-doped porous carbon electrocatalyst and process for preparation thereof
CN106927556A (en) * 2017-03-28 2017-07-07 天津泰达环保有限公司 A kind of method of electrolysis advanced treatment of landfill leachate
CN109395777A (en) * 2018-04-12 2019-03-01 常州大学 A kind of Three-element composite photocatalyst BiOI@UIO-66 (NH2)@g-C3N4Preparation method
CN109012607A (en) * 2018-08-10 2018-12-18 南通寰宇博新化工环保科技有限公司 A kind of nanocomposite and preparation method thereof
CN109046425A (en) * 2018-08-13 2018-12-21 山东交通学院 Composite photo-catalyst TiO derived from a kind of MOF base2/g-C3N4Preparation method
CN109126893A (en) * 2018-10-09 2019-01-04 华东师范大学 A kind of oxidation of coal titanium-metal organic frame composite material and preparation method and application

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Construction of g-C3N4/PDI@MOF heterojunctions for the highly efficient visible light-driven degradation of pharmaceutical and phenolic micropollutants;Yuanyuan Li,等;《Web of science APPLIED CATALYSIS B-ENVIRONMENTAL》;ELSEVIER SCIENCE;20190805;摘要 *

Also Published As

Publication number Publication date
CN110615501A (en) 2019-12-27

Similar Documents

Publication Publication Date Title
Deng et al. Treatment of organic wastewater containing nitrogen and chlorine by combinatorial electrochemical system: Taking biologically treated landfill leachate treatment as an example
Li et al. Removal of trivalent chromium in the complex state of trivalent chromium passivation wastewater
CN104496089A (en) Treatment method for heavy metal wastewater containing degradation-resistant organic matters
CN104773888A (en) Iron-carbon inner electrolysis-Fenton oxidation-electrolytic electrocatalytic oxidation combined wastewater treatment method and device
CN110615501B (en) Method for treating landfill leachate
Li et al. Efficient electrochemical oxidation of thallium (I) in groundwater using boron-doped diamond anode
Pahat Optimization of cod and colour removal from landfill leachate by electro-fenton method
CN110357217A (en) A kind of application of the fixed iron powder electrode of magnetic force in the treatment of waste water
CN102329048B (en) Method for treating wastewater produced during chemical synthesis of vitamin B6
CN102040309A (en) Combined treatment process for urban garbage percolate
CN107585953A (en) A kind of benzoic methyl nitroazole method of wastewater treatment
CN104787860A (en) Method for treating hexavalent chromium in waste water by utilizing metal semi-fuel cell
CN116177716A (en) Experimental device and method for treating tetracycline wastewater through electro-Fenton reaction of cathode of microbial fuel cell
CN111333235A (en) Landfill leachate treatment system and process
CN104609612A (en) Landfill leachate electrochemical treatment method
CN105417800B (en) A kind of method that environmental protection removes nitrate nitrogen in waste water
Si et al. Effect of current density on groundwater arsenite removal performance using air cathode electrocoagulation
CN114797754B (en) Method for preparing efficient wastewater adsorbent by utilizing boric sludge
CN116282470A (en) Advanced treatment method for organic pollutants in landfill leachate
CN111333152A (en) Method for treating high-concentration nickel-phosphorus-containing organic waste liquid through electrolytic oxidation
CN102897921B (en) Mineralized refuse participating organic waste water electro-Fenton treatment method
CN110255784B (en) Method for synchronously removing nitrogen and phosphorus in pig-raising wastewater
CN104192955A (en) Method for treating ultrafiltration-concentrated solution generated in waste leachate membrane treatment process
CN108017136A (en) A kind of method that poisonous Cr VI is changed into trivalent chromium using organic matter
CN106007004A (en) Method for strengthening treatment of chromium-containing wastewater by using other heavy metal wastewater

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
TR01 Transfer of patent right
TR01 Transfer of patent right

Effective date of registration: 20220810

Address after: 312000 1201, 12th floor, building 3, Science Park, shuimuwan District, Shaoxing, Zhejiang, China

Patentee after: Zhejiang Huike Environmental Protection Technology Co.,Ltd.

Address before: 215500 Changshou City South Three Ring Road No. 99, Suzhou, Jiangsu

Patentee before: CHANGSHU INSTITUTE OF TECHNOLOGY