Municipal solid waste(MSW)is an important destination for abandoned plastics.During the waste disposal process,large plastic debris is broken down into microplastics(MPs)and released into the leachate.However,current ...Municipal solid waste(MSW)is an important destination for abandoned plastics.During the waste disposal process,large plastic debris is broken down into microplastics(MPs)and released into the leachate.However,current research only focuses on landfill leachates,and the occurrence of MPs in other leachates has not been studied.Therefore,herein,the abundance and characteristics of MPs in three types of leachates,namely,landfill leachate,residual waste leachate,and household food waste leachate,were studied,all leachates were collected from the largest waste disposal center in China.The results showed that the average MP abundances in the different types of leachates ranged from(129±54)to(1288±184)MP particles per liter(particlesL1)and the household food waste leachate exhibited the highest MP abundance(p<0.05).Polyethylene(PE)and fragments were the dominant polymer type and shape in MPs,respectively.The characteristic polymer types of MPs in individual leachates were different.Furthermore,the conditional fragmentation model indicated that the landfilling process considerably affected the size distribution of MPs in leachates,leading to a higher percentage(>80%)of small MPs(20–100 lm)in landfill leachates compared to other leachates.To the best of our knowledge,this is the first study discussing the sources of MPs in different leachates,which is important for MP pollution control during MSW disposal.展开更多
Jatropha curcas L. commonly known as “physic nut” is an exotic species that shows invasive characters. Plantation of Jatropha species is being undertaken at a large scale for biodiesel production. The plants defolia...Jatropha curcas L. commonly known as “physic nut” is an exotic species that shows invasive characters. Plantation of Jatropha species is being undertaken at a large scale for biodiesel production. The plants defoliate their leaves twice a year and have been shown to possess certain antinutritional factors. Seeds of Jatropha are removed from mature dried fruits for oil extraction and ovary walls are discarded. For the present experiments leachates from sun dried leaves and ovary walls of Jatropha curcas L. were used for analyzing their possible allelopathic effects on the growth of wheat (Triticum aestivum L. cultivar, MP-4010). Leachate treatments result in slight decrease in growth in terms of plant height, leaf area, biomass, spike length and 100 seed weight of wheat and increase in total phenols, tannins, phytic acid and free amino acids. Results suggest that the leachates of leaf and ovary wall of Jatropha curcas are slightly inhibitory, however the impact does not last long. Nevertheless, continuous plantation may lead to accumulation of damaging constituents which reflects the need for further analysis and experimentation.展开更多
Management of MSW(Municipal Solid Waste)is a major downside in most of the biggest cities.The composting of the organic fraction of MSW is one of the oldest and simplest ways of organic waste stabilization.It is a sel...Management of MSW(Municipal Solid Waste)is a major downside in most of the biggest cities.The composting of the organic fraction of MSW is one of the oldest and simplest ways of organic waste stabilization.It is a self-heating biological conversion that generates appropriate finished merchandise such as soil conditioner or fertilizers.Mexico City generates about 12,500 ton/day of MSW,44%of it is food scraps and yard trimmings which are the OFMSW(Organic Fraction of Municipal Solid Waste),2,500 ton/day of it is composted at the BPCP(Bordo Poniente Composting Plant)yielding 500 ton/day of compost.The purpose of this study was to evaluate three treatments to accelerate the composting process,so eventually the city could increase the amount of the OFMSW at BPCP.We compared three different treatments;one of them showed a significant reduction in time of the composting process(p≤0.05)i.e.,it took less time to reach the thermophilic stage,maturity and stabilization phases.Maturity was achieved at 35 days and 60 days to stabilize.We conclude that shredding the feedstock plus leachate inoculum addition at the beginning of the process,reduces the composting time in about 61%with respect to the time it takes at the BPCP,where lasted 90 days.展开更多
Landfill leachates with different ages (mature leachate, 11 years; semi-mature leachate, 5 years; fresh leachate, under operation) were collected from Laogang Refuse Landfill, Shanghai to characterize the colloid si...Landfill leachates with different ages (mature leachate, 11 years; semi-mature leachate, 5 years; fresh leachate, under operation) were collected from Laogang Refuse Landfill, Shanghai to characterize the colloid size distribution and variations of leachate. These leachates were separated using micro-filtration and ultra-filtration into specific size fractions, i.e., suspended particles (SP) (〉 1.2 μm), coarse colloids (CC) (1.2-0.45 μm), fine colloids (FC) (0.45 m, 5 kDa/1 kDa molecular weight (MW)), and dissolved organic matters (DM, 〈 5 kDa/1 kDa MW). The specific colloids in each size fraction were quantified and characterized through chemical oxygen demands (COD), total solid (TS), pH, NH4^+-N, total organic carbon (TOC) and fixed solid (FS). It was found that COD, NH^4+-N and TS in leachate decreased significantly over ages, while pH increased. The dissolved fractions (〈 5 kDa/1 kDa) dominated (over 50%) in three leachates in terms of COD, and the organic matter content in dissolved fraction of leachates decreased and the inorganic matter increased as the disposal time extended, with the TOC/COD ratio 30%-7%. Dissolved fractions decreased from 82% to 40% in terms of TOC as the disposal time extended, suggested that the organic matter remained in leachate would form into middle molecular weight substances during the degradation process.展开更多
Soil microbes may be critical players in determining the allelopathic potential of some plants. Low levels of plant community biodiversity in Eucalyptus plantations have been attributed to the allelopathic potential o...Soil microbes may be critical players in determining the allelopathic potential of some plants. Low levels of plant community biodiversity in Eucalyptus plantations have been attributed to the allelopathic potential of these tree species. The role of soil microbes in the allelopathic effect of leaf leachates of the hybrid tree Eucalyptus grandis x E. urophylla, was tested in Petri dish assays with Brassica chinensis as a receiver plant. Soils were collected from either a local garden (soil A) or a Eucalyptus plantation (soil B) and half of each soil was sterilized to remove microbes. These soils were then treated with E. grandis x E. urophylla leachates for 0-72 h. Seed germination of B. chinensis was significantly inhibited in soils treated with leaf leachates relative to untreated soils. The inhibitory effect of the leaf leachates was more pronounced in sterilized soils. Total phenolic content was obvious lower in nonsterile leachate-treated soils than in sterile soils. Biomass of B. chinensis was negatively correlated with the total phenolic content in soils. Our findings suggest that soil microbes can alleviate the allelopathic potential of Eucalyptus and thereby its negative impact on plant growth.展开更多
A comprehensive assessment of heavy metals and organic content was performed for leachates produced from a number of old and new landfills in Jordanover 9 month in efforts to set a framework for treatment regulations....A comprehensive assessment of heavy metals and organic content was performed for leachates produced from a number of old and new landfills in Jordanover 9 month in efforts to set a framework for treatment regulations. All leachates were basic (pH = 7 - 9) and have high electric conductivity and high organic contents (COD = 3000 - 500,000 mg/L, TOC= 500 - 21,000 mg/L). The organic content was inversely proportional to the age of landfill. Heavy metals analysis showed no significant threat of Co, Zn, Pb and Al in any site. Meanwhile, the concentrations of Cr, Mn, Ni, Cd and As were high, exceeding local and international standard limits. Typical physical, chemical and biological treatments can be employed to upgrade the leachates of the active Ghabawi and Akaider sites. Whereas for the high organic strength of Russeifeh, an adsorption treatment by activated carbon is recommended.展开更多
The quantitative and qualitative composition of Chinese municipal solid waste (MSW) differs significantly from German waste. The focus of this paper is on whether these differences also lead to dissimilar qualities of...The quantitative and qualitative composition of Chinese municipal solid waste (MSW) differs significantly from German waste. The focus of this paper is on whether these differences also lead to dissimilar qualities of leachates during storage or landfilling. Leachates ingredients determine the appropriate treatment technique. MSW compositions of the two cities Guilin (China) and Essen (Germany), each with approx. 600 000 inhabitants, are used to simulate Chinese and German MSW types. A sequencing batch reactor (SBR) is used, combining aerobic and anaerobic reaction principles, to test the biodegradability of leachates. Leachates are tested for temperature, pH-value, redox potentials, and oxygen concentration. Chemical oxygen demand (COD) values are determined. Within 8 h, the biodegradation rates for both kinds of leachates are more than 90%. Due to the high organic content of Chinese waste, the degradation rate for Guilin MSW leachate is even higher, up to 97%. The effluent from SBR technique is suitable for direct discharge into bodies of water.展开更多
The research intends to bring out the contribution of leachate on groundwater in two dumpsites in Nguru and Potiskum all in Yobe state,Nigeria.A total of seven(7)and eight(8)VES by Schlumberger electrode with the use ...The research intends to bring out the contribution of leachate on groundwater in two dumpsites in Nguru and Potiskum all in Yobe state,Nigeria.A total of seven(7)and eight(8)VES by Schlumberger electrode with the use of Wenner electrode configuration.The results were interpreted by the use of WinRESIST for VES and IPWIN2INV for ERT.The study pointed out that,the area in question is comprised of four layers of geoelectric such as the topsoil,clay,sand,sandy clay and sand.The range of the first resistivity layer was from 6.16Ωm to 332Ωm in the first geo-electric layer and its thickness range from 2.77 m to 37.7 m and a depth range of 2.77 m to 37.7 m.the range of the second resistivity layer was from 16.5Ωm to 37.9Ωm which has the range of its thickness from 4.1 m to 10.7 m.The range of the third resistivity layer was from 101.2Ωm to 288.2Ωm which has the range of its thickness from 38.9 m to 99.7 m,and the first aquifer in the area.The range of the first resistivity layer was from 100.7Ωm to 214.3Ωm which has the range of its thickness from 28.5 m to 94 m.The fifth layer which is the second aquifer and has resistivity from 254Ωm to 350Ωm with a very large thickness.The range of the first resistivity aquifer is from 101.2Ωm to 288.2Ωm and the range of the second resistivity aquifer is from 253.8Ωm to 350.1Ωm.The 2D ERT profiles unveiled areas with low resistant zones and later discussed as zones penetrated by contaminants originated from dumpsites whereas high resistant zones represent areas of low or non-conductive materials in the area.Data obtained from four dumpsites indicated that leachate of the waste dumpsites penetrated into aquifers and polluted the groundwater.The existence of contaminants in the water was noted by a decrease in the formation resistant values.It is seen,from the results of the survey(geophysical)that the water in the area is polluted and it accounts for the prevalence of any disease related to water that are common in the area.展开更多
Terrestrial invasive alien weed plants are known to infest cultivated land, potentially releasing allelochemicals into the rhizosphere during decomposition, negatively impacting crop growth. This study aimed to evalua...Terrestrial invasive alien weed plants are known to infest cultivated land, potentially releasing allelochemicals into the rhizosphere during decomposition, negatively impacting crop growth. This study aimed to evaluate: (1) the allelopathic activity of five invasive weed species (Ageratum conyzoides, Bidens pilosa, Cecropia peltata, Tithonia diversifolia, and Chromolaena odorata) on Lactuca sativa and Phaseolus vulgaris growth;and (2) the effects of A. conyzoides rhizospheric soil on P. vulgaris seed germination. Bioassays of aqueous and leachate extracts were prepared from fresh leaves of the invasive species at concentrations of 0%, 25%, 50%, 75%, and 100% to assess allelopathic effects on L. sativa and P. vulgaris seed germination. Additionally, rhizospheric soil from A. conyzoides stands was collected, processed, and applied at varied weights (0.5 - 7 kg) to P. vulgaris seeds, with germination observed over nine days. Polynomial regression analysis was applied to model the data. High-concentration extracts (75% and 100%) significantly inhibited germination, root, and shoot growth in both L. sativa and P. vulgaris (P 2 − 80.294922x3 + 41.541115x4 − 11.747532x5 + 1.8501702x6 − 0.1519795x7 + 0.0050631x8. Allelopathic effects were concentration-dependent, with roots more sensitive than shoots to the invasive extracts. L. sativa was the most susceptible, while P. vulgaris showed greater tolerance. Modelling the allelopathic impact of A. conyzoides rhizospheric soil offers valuable insight into the allelochemical dosage necessary to affect seed germination, informing potential agricultural management strategies for invasive plant control.展开更多
In the present study,the seasonal concentrations of polybrominated diphenyl ethers(PBDEs)in leachate and sediment samples,and the influence of geomembrane liners on PBDE levels and the extent of their infiltration int...In the present study,the seasonal concentrations of polybrominated diphenyl ethers(PBDEs)in leachate and sediment samples,and the influence of geomembrane liners on PBDE levels and the extent of their infiltration into groundwater on selected landfill sites in Gauteng Province,South Africa were determined.Leachate and sediment samples were collected from seven operational landfill sites namely:Goudkoppies,Robinson Deep,Marie Louis,Soshanguve,Onderstepoort,Hatherly and Garankuwa from Johannesburg and Pretoria,in winter and summer.Groundwater samples were collected from monitoring boreholes from two landfill sites.Liquid-liquid and Soxhlet extraction techniques were employed for the extraction of leachate and groundwater,and sediment respectively using dichloromethane.The extracted samples were subjected to column clean up and,thereafter,analysed using gas chromatographyemass spectroscopy(GC-MS).PBDEs selected for the study were:BDE-17,-28,-47,-100,-99,-153,-154,-183 and-209.The P9PBDE concentrations in leachate samples for winter and summer ranged from 0.316e1.36 ng L-1 and 0.560e1.08 ng L-1 respectively.The P9 PBDE concentrations obtained for sediment in winter and summer were 3.00e4.91 ng g-1 and 2.50e3.71 ng g-1 respectively.Winter samples exhibited higher(p<0.05)concentrations for both leachate and sediment samples compared to summer samples.This trend was attributed to high precipitation rate in summer which may have infiltrated into the landfills,subsequently diluting the leachate and sediment samples.In contrast,the winter period is generally dry and PBDEs are,therefore,more likely to be concentrated.The concentrations of PBDEs in leachate and sediment samples were higher in landfill sites with geomembrane liners compared to those without liners.Groundwater samples taken from the vicinity of selected landfill sites without geomembrane liners exhibited high concentrations of P9PBDEs,indicating possible migration of PBDEs from landfill site into groundwater.Pearson correlation(r)and statistical significant t-test(p)for the PBDE congeners versus dissolved organic carbon(DOC)resulted in positive moderate interactions with a statistical significance for most congeners.Suggesting that there is a possible influence of organic carbon on the levels of PBDEs.展开更多
Identifying potential sources of pharmaceuticals and personal care products(PPCPs)in the environment is critical for the effective control of PPCP contamination.Landfill leachate is an important source of PPCPs in wat...Identifying potential sources of pharmaceuticals and personal care products(PPCPs)in the environment is critical for the effective control of PPCP contamination.Landfill leachate is an important source of PPCPs in water;however,it has barely been involved in source apportionment due to the lack of indicator-PPCPs(i-PPCPs)in landfill leachates.This study provides the first systematic framework for identifying i-PPCPs for landfill leachates based on the wide-scope target monitoring of PPCPs.The number of target PPCPs increased from<20 in previous studies to 68 in the present study.Fifty-nine PPCPs were detected,with median concentrations in leachate samples ranging from below the method quantification limit(MQL)to 41μg/L,and 19 of them were rarely reported previously.A total of 29 target compounds were determined to be PPCPs of high concern by principal component analysis according to multiple criteria,including occurrence,exposure potential,and ecological effect.Coupled with source-specificity and representativeness analysis,erythromycin,gemfibrozil,and albendazole showed a significant difference in their occurrence in leachate compared to other potential sources(untreated and treated municipal wastewater and livestock wastewater)and correlated with total PPCP concentrations;these were recommended as i-PPCPs for leachates.Indicator screening procedure can be used to develop a sophisticated source apportionment method to identify sources of PPCPs from adjacent landfills.展开更多
Rare earth elements(REEs) were extracted from phosphogypsum(PG) using an indirect leaching method that produces CaCO_(3).The carbonation process transforms PG into CaCO_(3),and a potential source of value is the(NH_(4...Rare earth elements(REEs) were extracted from phosphogypsum(PG) using an indirect leaching method that produces CaCO_(3).The carbonation process transforms PG into CaCO_(3),and a potential source of value is the(NH_(4))_(2)SO_(4) fertilizer.The calcium carbonate byproduct is rich in REEs that are originally present in PG.Calcium carbonate,a byproduct of PG carbonation and a rich source of REEs,could dissolve in nitric acid to produce a calcium nitrate leach solution that contains RE nitrate.Subsequently,the most widely used solvent extraction technique can make use of an environmentally benign nitrate ionic liquid.Cyphos IL 101(trihexyl(tetradecyl)phosphonium chloride) is transformed into trihexyl(tetradecyl)phosphonium nitrate([P_(66614)][NO_(3)]) ionic liquid by adding 2.5 mol/L potassium nitrate.The extraction examinations were tested by equilibration of 2 mL of [P_(66614)][NO_(3)] with 2 mL of a synthetic solution of 1000 mg/L of individual La,Ce,and Nd to gain the optimal extraction conditions.The high extraction efficiency of La,Ce,and Nd was gained by stirring a 1/1 aqueous/organic phase ratio and 3 mol/L NH_(4)NO_(3)(as salting out) at 800 r/min for 40 min at 50℃ to decrease the viscosity of [P_(66614)][NO_(3)].The La(Ⅲ),Ce(Ⅲ),and Nd(Ⅲ) stripping efficiencies were examined from their loaded [P_(66614)][NO_(3)] ionic liquid by 1/1 A/O ratio of acidified water,800 r/min stirring speed,and 25℃.After nine cycles,the extraction and stirring efficiency for the La,Ce,and Nd drop to about 80%.The extraction and stripping parameters are applied to the RE leachate from PG to gain the RE oxide with an assay of 92.67%.展开更多
Anaerobic digestion(AD),as an eco-friendly biological process,shows potential for the decomposition of leachate produced by waste incineration power plants.In this study,the effects of Fe oxides nano-modified pumice(F...Anaerobic digestion(AD),as an eco-friendly biological process,shows potential for the decomposition of leachate produced by waste incineration power plants.In this study,the effects of Fe oxides nano-modified pumice(FNP)were investigated on the fresh leachate AD process.Firstly,a simple hydrothermal method was used to prepare FNP,then introduced into the UASB reactor to evaluate its AD efficiency.Results showed that the inclusion of FNP could shorten the lag phase by 10 days compared to the control group.Furthermore,cumulative methane production in the FNP group was enhanced by 20.11%.Mechanistic studies suggested that hydrogenotrophic methanogenesis in the FNP group was more pronounced due to the influence of key enzymes(i.e.,dehydrogenase and coenzyme F420).Microbial community analysis demonstrated that FNP could enhance the abundance of Methanosarcina,Proteobacteria,Sytrophomonas,and Limnobacter,which might elevate enzyme activity involved in methane production.These findings suggest that FNP might mediate interspecies electron transfer among these microorganisms,which is essential for efficient leachate treatment.展开更多
Conventional hydrometallurgy recycling process for treating wasted lithium-ion batteries(LIBs)typically results in the consumption of large amounts of corrosive leachates.Recent research on reusable leachate is expect...Conventional hydrometallurgy recycling process for treating wasted lithium-ion batteries(LIBs)typically results in the consumption of large amounts of corrosive leachates.Recent research on reusable leachate is expected to significantly improve the economic and environmental benefits,but is usually limited to specific and unique chemical reactions which could only apply to one type of metal elements.Herein,we report the co-extraction of multiple metal elements can be extracted without adding precipitates by mixed crystal co-precipitation,which enables the reusability of the leachate.We show that an oxalic acid(OA):choline chloride(ChCl):ethylene glycol(EG)type DES leachate system can leach transition metals from wasted LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)(NCM)cathode materials with satisfactory efficiency(The time required for complete leaching at 120℃ is 1.5 h).The transition metals were then efficiently extracted(with a recovery efficiency of over 96%for all elements)by directly adding water without precipitants.Noteworthy,the leachate can be efficiently recovered by directly evaporating the added water.The successful realization of reusability of leachate for the synergistic extraction of multiple elements relies on the regulation of the mixed crystal co-precipitation coefficient,which is realized by rationally design the reaction condition(composition of leachate,temperature and time)and induces the extraction of originally soluble manganese element.Our strategy is expected to be generally applicable and highly competent for industrial applications.展开更多
Leachate sludge,a byproduct of municipal solid waste leachate treated through biochemical processes,is characterized by high water content(761.1%)and significant organic matter content(71.2%).Cement that is commonly u...Leachate sludge,a byproduct of municipal solid waste leachate treated through biochemical processes,is characterized by high water content(761.1%)and significant organic matter content(71.2%).Cement that is commonly used for solidifying leachate sludge has shown limited effectiveness.To address this issue,an alkali-activated ground-granulated blast-furnace slag(GGBS)geopolymer blended with polypropylene fibers was developed to solidify leachate sludge.Moreover,unconfined compressive strength(UCS),immersion,as well as X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and scanning electron microscope(SEM)tests were conducted to investigate the solidification effect and mechanism of the GGBS-based geopolymer and fibers on leachate sludge.The results showed that:the 28-d UCS of the solidified sludge with 20%and 30%GGBS is 0.35 MPa and 1.85 MPa,and decreases to 0.18 MPa and 1.13 MPa,respectively,after soaked in water for 28 d.Notably,the UCS of the solidified sludge with 30%GGBS satisfied the strength requirement of roadbed materials.Polypropylene fibers significantly enhanced the strength,ductility and water stability of the solidified sludge,with an optimal fiber content of 0.3%.Alkali-activated GGBS geopolymer generated three-dimensional,cross-linked geopolymeric gels within the solidified sludge,cementing sludge particles and filling intergranular pores to form a stable cementitious structure,thereby achieving effective solidification.Furthermore,incorporating polypropylene fibers improved the bonding and anchoring effect between fiber and solidified sludge,constrained lateral deformation of the solidified sludge,restricted crack propagation,and enhanced engineering performance of the solidified leachate sludge.展开更多
Bioremediation has gained significant attention due to its potential to remove azo dyes.However,the challenges microor-ganisms face in surviving when azo dyes are the sole carbon source limit its widespread applicatio...Bioremediation has gained significant attention due to its potential to remove azo dyes.However,the challenges microor-ganisms face in surviving when azo dyes are the sole carbon source limit its widespread application.This study aimed to improve the biodegradation of azo dyes by utilizing Baijiu distiller’s grains leachate(BDGL)as a co-substrate.The experimental results demon-strated that BDGL significantly enhanced Providencia rettgeri’s ability to degrade the model pollutant Acid Black 210(AB210),achieving a decolorization efficiency of 94.5%.This may be attributed to the nutrient-rich composition of BDGL,which includes ethanol and protein,providing a favorable substrate for bacterial growth and activity.The higher biomass and increased activities of azoreductase and quinone oxidoreductase in the BDGL group further supported these findings.Additionally,this method demonstra-ted broad-spectrum degradation of azo dyes(Direct Red 5B,Acid Red 73,and Congo Red)with different structures,highlighting its potential applicability.Metabolite assays combined with transcriptomics analyses revealed that the expression of functional genes re-lated to redox reactions,azo bond cleavage,and hydrolysis increased under the co-metabolic conditions of BDGL,resulting in stronger reducing power that further mineralized the dye into smaller metabolites.Our study offers a practical strategy for the simulta-neous treatment of dye-containing wastewater and Baijiu distiller’s grains,with significant environmental and industrial applications.展开更多
Antibiotics,as emerging pollutants,pose significant risks to aquatic ecosystems and human health by disrupting the endocrine systems of aquatic organisms and affecting ecosystem stability through food chain enrichment...Antibiotics,as emerging pollutants,pose significant risks to aquatic ecosystems and human health by disrupting the endocrine systems of aquatic organisms and affecting ecosystem stability through food chain enrichment.In a study conducted in Hebei Province,China,liquid chromatography-triple quadrupole-linear ion trap mass spectrometry(LC-TQ-LIT-MS)was used to analyze 90 different antibiotics in 31 water samples,including surface water,groundwater,and waste leachate from three urban landfills.This analysis included hormones,broad-spectrum antimicrobials,macrolides,tetracyclines,β-lactams,sulfonamides,and quinolones.The study’s results indicated that quinolones,β-lactams,and macrolides were the most frequently detected substances in the landfills.It is noteworthy that the concentrations of these antibiotics varied significantly among different cities,reflecting local production and living characteristics.The results of the tests showed that the concentration of amoxicillin was 1171 ng/L in surface water,811 ng/L in groundwater,and 1926 ng/L of ciprofloxacin in waste leachate.Furthermore,a consistent pattern was observed between the compounds present in the leachate,groundwater,and surface water at the three sites.Risk assessments revealed that the ecological risk was higher for surface water and lower for groundwater.This study is the first to systematically analyze the pollution status of antibiotics and hormones in the water around the landfill in Hebei Province,which not only fills the blank of groundwater-related research in Hebei Province but also provides key data support and theoretical basis for local groundwater hydrological and environmental detection and pollution prevention.展开更多
As the global electric vehicle market continues to grow,the recycling of Li-ion battery (LIB) becomes more important worldwide and the resynthesis of cathode materials would be the most value-added recycling approach ...As the global electric vehicle market continues to grow,the recycling of Li-ion battery (LIB) becomes more important worldwide and the resynthesis of cathode materials would be the most value-added recycling approach taking into account limited metal resources.Although resynthesized homogenous LiNi_(x)Co_(y)Mn_(z)O_(2)(NCM) from spent LIB leachate shows comparable battery performance to pristine NCM from virgin materials,there is general concern in its cycling performance.Here,we synthesize core–shell(CS) Ni-rich NCM,which consists of Ni-rich NCM as the core and NCM derived from the original or purified leachate of spent LIBs as the shell.Resynthesized CS Ni-rich NCM exhibits improved rate capability resulting from expanded interslab thickness in the NCM structure.CS Ni-rich NCM from purified LIB leachate shows improvement in cycling performance and thermal stability.It specifically delivers a capacity retention of 86.6%at a high temperature after 80 cycles compared to that (75.0%) of pristine CS Ni-rich NCM.These improvements are caused by a relatively high Mg content on the shell and the widespread distribution of Al through the CS structure.CS Ni-rich NCM derived from spent LIB leachate provides a new alternative approach to conventional LIB recycling methods,which would utilize efficiently limited metal resources for the sustainable LIB production.展开更多
Humic acid(HA)is a typical refractory organicmatter,so it is of great significance to investigate its effect on the performance of Anammox granular sludge.When the dosage ofHA≤50 mg/L,HA promotes the total nitrogen r...Humic acid(HA)is a typical refractory organicmatter,so it is of great significance to investigate its effect on the performance of Anammox granular sludge.When the dosage ofHA≤50 mg/L,HA promotes the total nitrogen removal rate(NRR)to 1.45 kg/(m^(3)·day).When HA was between 50 and 100 mg/L,the NRR of Anammox was stable.At this time,the adsorption of HA causes the sludge to gradually turn fromred to brown,but the activities of heme and enzymes showed that its capacitywas not affected.When HA levels reached 250 mg/L,the NRR dropped to 0.11 kg/(m^(3)·day).Moderate HA levels promoted the release of extracellular polymeric substance(EPS),but excessive HA levels lead to a decrease in EPS concentrations.HA inhibited Anammox activity,which indirectly hindered the transmission of substrate and accumulated substrate toxicity.Although HA promoted the increase of heterotrophicmicrobial abundance in Anammox system,the microbial diversity decreased gradually.With the increase of HA concentration,the abundance of Candidatus_Brocadia,the main functional microorganism of Anammox system,decreased gradually,while the abundance of Candidatus_Kuenenia increased gradually.展开更多
Groundwater contamination near landfills is commonly caused by leachate leakage,and permeable reactive barriers(PRBs)are widely used for groundwater remediation.However,the deactivation and blockage of the reactive me...Groundwater contamination near landfills is commonly caused by leachate leakage,and permeable reactive barriers(PRBs)are widely used for groundwater remediation.However,the deactivation and blockage of the reactive medium in PRBs limit their long-term effectiveness.In the current study,a new methodology was proposed for the in situ regeneration of PRB to remediate leachate-contaminated groundwater.CO_(2)coupled with oxidants was applied for the dispersion and regeneration of the fillers;by injecting CO_(2)to disperse the fillers,the permeability of the PRB was increased and the oxidants could flow evenly into the PRB.The results indicate that the optimumfiller proportion was zero-valent iron(ZVI)/zeolites/activated carbon(AC)=3:8:10 and the optimum oxidant proportion was COD/Na_(2)S_(2)O_(8)/H_(2)O_(2)/Fe^(2+)=1:5:6:5;the oxidation system of Fe^(2+)/H_(2)O_(2)/S_(2)O_(8)^(2−)has a high oxidation efficiency and persistence.The average regeneration rate of zeolites was 72.71%,and the average regeneration rate of AC was 68.40%;the permeability of PRB also increased.This technology is effective for the remediation of landfills in China that have large contaminated areas,an uneven pollutant concentration distribution,and a long pollution duration.The purification mode of long-term adsorption and short-time in situ oxidation can be applied to the remediation of long-term high-concentration organically polluted groundwater,where pollution sources are difficult to cut off.展开更多
基金supported by the National Key Research and Development Program of China(2023YFC3711600)the National Natural Science Foundation of China(22076045 and 22376066)the Shanghai Talent Development Funding,and the Shanghai Youth Talent Support Program.
文摘Municipal solid waste(MSW)is an important destination for abandoned plastics.During the waste disposal process,large plastic debris is broken down into microplastics(MPs)and released into the leachate.However,current research only focuses on landfill leachates,and the occurrence of MPs in other leachates has not been studied.Therefore,herein,the abundance and characteristics of MPs in three types of leachates,namely,landfill leachate,residual waste leachate,and household food waste leachate,were studied,all leachates were collected from the largest waste disposal center in China.The results showed that the average MP abundances in the different types of leachates ranged from(129±54)to(1288±184)MP particles per liter(particlesL1)and the household food waste leachate exhibited the highest MP abundance(p<0.05).Polyethylene(PE)and fragments were the dominant polymer type and shape in MPs,respectively.The characteristic polymer types of MPs in individual leachates were different.Furthermore,the conditional fragmentation model indicated that the landfilling process considerably affected the size distribution of MPs in leachates,leading to a higher percentage(>80%)of small MPs(20–100 lm)in landfill leachates compared to other leachates.To the best of our knowledge,this is the first study discussing the sources of MPs in different leachates,which is important for MP pollution control during MSW disposal.
文摘Jatropha curcas L. commonly known as “physic nut” is an exotic species that shows invasive characters. Plantation of Jatropha species is being undertaken at a large scale for biodiesel production. The plants defoliate their leaves twice a year and have been shown to possess certain antinutritional factors. Seeds of Jatropha are removed from mature dried fruits for oil extraction and ovary walls are discarded. For the present experiments leachates from sun dried leaves and ovary walls of Jatropha curcas L. were used for analyzing their possible allelopathic effects on the growth of wheat (Triticum aestivum L. cultivar, MP-4010). Leachate treatments result in slight decrease in growth in terms of plant height, leaf area, biomass, spike length and 100 seed weight of wheat and increase in total phenols, tannins, phytic acid and free amino acids. Results suggest that the leachates of leaf and ovary wall of Jatropha curcas are slightly inhibitory, however the impact does not last long. Nevertheless, continuous plantation may lead to accumulation of damaging constituents which reflects the need for further analysis and experimentation.
基金This work was supported by the Institute of Science and Technology of Mexico City and the Ministry of Works and Services of the Government of Mexico City.
文摘Management of MSW(Municipal Solid Waste)is a major downside in most of the biggest cities.The composting of the organic fraction of MSW is one of the oldest and simplest ways of organic waste stabilization.It is a self-heating biological conversion that generates appropriate finished merchandise such as soil conditioner or fertilizers.Mexico City generates about 12,500 ton/day of MSW,44%of it is food scraps and yard trimmings which are the OFMSW(Organic Fraction of Municipal Solid Waste),2,500 ton/day of it is composted at the BPCP(Bordo Poniente Composting Plant)yielding 500 ton/day of compost.The purpose of this study was to evaluate three treatments to accelerate the composting process,so eventually the city could increase the amount of the OFMSW at BPCP.We compared three different treatments;one of them showed a significant reduction in time of the composting process(p≤0.05)i.e.,it took less time to reach the thermophilic stage,maturity and stabilization phases.Maturity was achieved at 35 days and 60 days to stabilize.We conclude that shredding the feedstock plus leachate inoculum addition at the beginning of the process,reduces the composting time in about 61%with respect to the time it takes at the BPCP,where lasted 90 days.
基金supported by the State Key Laboratory of Pollution Control and Resource Reuse Foundation(No.PCRRF09008)the Key Project of Science and Technology Commission of Shanghai Municipality (No.08Dz1202800)
文摘Landfill leachates with different ages (mature leachate, 11 years; semi-mature leachate, 5 years; fresh leachate, under operation) were collected from Laogang Refuse Landfill, Shanghai to characterize the colloid size distribution and variations of leachate. These leachates were separated using micro-filtration and ultra-filtration into specific size fractions, i.e., suspended particles (SP) (〉 1.2 μm), coarse colloids (CC) (1.2-0.45 μm), fine colloids (FC) (0.45 m, 5 kDa/1 kDa molecular weight (MW)), and dissolved organic matters (DM, 〈 5 kDa/1 kDa MW). The specific colloids in each size fraction were quantified and characterized through chemical oxygen demands (COD), total solid (TS), pH, NH4^+-N, total organic carbon (TOC) and fixed solid (FS). It was found that COD, NH^4+-N and TS in leachate decreased significantly over ages, while pH increased. The dissolved fractions (〈 5 kDa/1 kDa) dominated (over 50%) in three leachates in terms of COD, and the organic matter content in dissolved fraction of leachates decreased and the inorganic matter increased as the disposal time extended, with the TOC/COD ratio 30%-7%. Dissolved fractions decreased from 82% to 40% in terms of TOC as the disposal time extended, suggested that the organic matter remained in leachate would form into middle molecular weight substances during the degradation process.
基金supported by the Sci-technology program of Guangxi Province(No.Guikezhong 1347001)
文摘Soil microbes may be critical players in determining the allelopathic potential of some plants. Low levels of plant community biodiversity in Eucalyptus plantations have been attributed to the allelopathic potential of these tree species. The role of soil microbes in the allelopathic effect of leaf leachates of the hybrid tree Eucalyptus grandis x E. urophylla, was tested in Petri dish assays with Brassica chinensis as a receiver plant. Soils were collected from either a local garden (soil A) or a Eucalyptus plantation (soil B) and half of each soil was sterilized to remove microbes. These soils were then treated with E. grandis x E. urophylla leachates for 0-72 h. Seed germination of B. chinensis was significantly inhibited in soils treated with leaf leachates relative to untreated soils. The inhibitory effect of the leaf leachates was more pronounced in sterilized soils. Total phenolic content was obvious lower in nonsterile leachate-treated soils than in sterile soils. Biomass of B. chinensis was negatively correlated with the total phenolic content in soils. Our findings suggest that soil microbes can alleviate the allelopathic potential of Eucalyptus and thereby its negative impact on plant growth.
文摘A comprehensive assessment of heavy metals and organic content was performed for leachates produced from a number of old and new landfills in Jordanover 9 month in efforts to set a framework for treatment regulations. All leachates were basic (pH = 7 - 9) and have high electric conductivity and high organic contents (COD = 3000 - 500,000 mg/L, TOC= 500 - 21,000 mg/L). The organic content was inversely proportional to the age of landfill. Heavy metals analysis showed no significant threat of Co, Zn, Pb and Al in any site. Meanwhile, the concentrations of Cr, Mn, Ni, Cd and As were high, exceeding local and international standard limits. Typical physical, chemical and biological treatments can be employed to upgrade the leachates of the active Ghabawi and Akaider sites. Whereas for the high organic strength of Russeifeh, an adsorption treatment by activated carbon is recommended.
基金Project supported by German Ministries of the State North Rhine-Westphalia
文摘The quantitative and qualitative composition of Chinese municipal solid waste (MSW) differs significantly from German waste. The focus of this paper is on whether these differences also lead to dissimilar qualities of leachates during storage or landfilling. Leachates ingredients determine the appropriate treatment technique. MSW compositions of the two cities Guilin (China) and Essen (Germany), each with approx. 600 000 inhabitants, are used to simulate Chinese and German MSW types. A sequencing batch reactor (SBR) is used, combining aerobic and anaerobic reaction principles, to test the biodegradability of leachates. Leachates are tested for temperature, pH-value, redox potentials, and oxygen concentration. Chemical oxygen demand (COD) values are determined. Within 8 h, the biodegradation rates for both kinds of leachates are more than 90%. Due to the high organic content of Chinese waste, the degradation rate for Guilin MSW leachate is even higher, up to 97%. The effluent from SBR technique is suitable for direct discharge into bodies of water.
文摘The research intends to bring out the contribution of leachate on groundwater in two dumpsites in Nguru and Potiskum all in Yobe state,Nigeria.A total of seven(7)and eight(8)VES by Schlumberger electrode with the use of Wenner electrode configuration.The results were interpreted by the use of WinRESIST for VES and IPWIN2INV for ERT.The study pointed out that,the area in question is comprised of four layers of geoelectric such as the topsoil,clay,sand,sandy clay and sand.The range of the first resistivity layer was from 6.16Ωm to 332Ωm in the first geo-electric layer and its thickness range from 2.77 m to 37.7 m and a depth range of 2.77 m to 37.7 m.the range of the second resistivity layer was from 16.5Ωm to 37.9Ωm which has the range of its thickness from 4.1 m to 10.7 m.The range of the third resistivity layer was from 101.2Ωm to 288.2Ωm which has the range of its thickness from 38.9 m to 99.7 m,and the first aquifer in the area.The range of the first resistivity layer was from 100.7Ωm to 214.3Ωm which has the range of its thickness from 28.5 m to 94 m.The fifth layer which is the second aquifer and has resistivity from 254Ωm to 350Ωm with a very large thickness.The range of the first resistivity aquifer is from 101.2Ωm to 288.2Ωm and the range of the second resistivity aquifer is from 253.8Ωm to 350.1Ωm.The 2D ERT profiles unveiled areas with low resistant zones and later discussed as zones penetrated by contaminants originated from dumpsites whereas high resistant zones represent areas of low or non-conductive materials in the area.Data obtained from four dumpsites indicated that leachate of the waste dumpsites penetrated into aquifers and polluted the groundwater.The existence of contaminants in the water was noted by a decrease in the formation resistant values.It is seen,from the results of the survey(geophysical)that the water in the area is polluted and it accounts for the prevalence of any disease related to water that are common in the area.
文摘Terrestrial invasive alien weed plants are known to infest cultivated land, potentially releasing allelochemicals into the rhizosphere during decomposition, negatively impacting crop growth. This study aimed to evaluate: (1) the allelopathic activity of five invasive weed species (Ageratum conyzoides, Bidens pilosa, Cecropia peltata, Tithonia diversifolia, and Chromolaena odorata) on Lactuca sativa and Phaseolus vulgaris growth;and (2) the effects of A. conyzoides rhizospheric soil on P. vulgaris seed germination. Bioassays of aqueous and leachate extracts were prepared from fresh leaves of the invasive species at concentrations of 0%, 25%, 50%, 75%, and 100% to assess allelopathic effects on L. sativa and P. vulgaris seed germination. Additionally, rhizospheric soil from A. conyzoides stands was collected, processed, and applied at varied weights (0.5 - 7 kg) to P. vulgaris seeds, with germination observed over nine days. Polynomial regression analysis was applied to model the data. High-concentration extracts (75% and 100%) significantly inhibited germination, root, and shoot growth in both L. sativa and P. vulgaris (P 2 − 80.294922x3 + 41.541115x4 − 11.747532x5 + 1.8501702x6 − 0.1519795x7 + 0.0050631x8. Allelopathic effects were concentration-dependent, with roots more sensitive than shoots to the invasive extracts. L. sativa was the most susceptible, while P. vulgaris showed greater tolerance. Modelling the allelopathic impact of A. conyzoides rhizospheric soil offers valuable insight into the allelochemical dosage necessary to affect seed germination, informing potential agricultural management strategies for invasive plant control.
基金The authors acknowledge the Water Research Commission(WRC-K8-850)South Africa for funding this research and Tshwane University of Technology for the facilitiesfinancial support for Sibiya IV for her masters'programme.
文摘In the present study,the seasonal concentrations of polybrominated diphenyl ethers(PBDEs)in leachate and sediment samples,and the influence of geomembrane liners on PBDE levels and the extent of their infiltration into groundwater on selected landfill sites in Gauteng Province,South Africa were determined.Leachate and sediment samples were collected from seven operational landfill sites namely:Goudkoppies,Robinson Deep,Marie Louis,Soshanguve,Onderstepoort,Hatherly and Garankuwa from Johannesburg and Pretoria,in winter and summer.Groundwater samples were collected from monitoring boreholes from two landfill sites.Liquid-liquid and Soxhlet extraction techniques were employed for the extraction of leachate and groundwater,and sediment respectively using dichloromethane.The extracted samples were subjected to column clean up and,thereafter,analysed using gas chromatographyemass spectroscopy(GC-MS).PBDEs selected for the study were:BDE-17,-28,-47,-100,-99,-153,-154,-183 and-209.The P9PBDE concentrations in leachate samples for winter and summer ranged from 0.316e1.36 ng L-1 and 0.560e1.08 ng L-1 respectively.The P9 PBDE concentrations obtained for sediment in winter and summer were 3.00e4.91 ng g-1 and 2.50e3.71 ng g-1 respectively.Winter samples exhibited higher(p<0.05)concentrations for both leachate and sediment samples compared to summer samples.This trend was attributed to high precipitation rate in summer which may have infiltrated into the landfills,subsequently diluting the leachate and sediment samples.In contrast,the winter period is generally dry and PBDEs are,therefore,more likely to be concentrated.The concentrations of PBDEs in leachate and sediment samples were higher in landfill sites with geomembrane liners compared to those without liners.Groundwater samples taken from the vicinity of selected landfill sites without geomembrane liners exhibited high concentrations of P9PBDEs,indicating possible migration of PBDEs from landfill site into groundwater.Pearson correlation(r)and statistical significant t-test(p)for the PBDE congeners versus dissolved organic carbon(DOC)resulted in positive moderate interactions with a statistical significance for most congeners.Suggesting that there is a possible influence of organic carbon on the levels of PBDEs.
基金supported by the National Natural Science Foundation of China(Nos.21777042 and 22076045)the Open Research Fund of State Environmental Protection Key Laboratory of Ecological Effect and Risk Assessment of Chemicals(China)(No.2022KFYB03)+1 种基金the Science and Technology Commission of Shanghai Municipality’s Yangfan Special Project(China)(No.23YF1408400)the project supported by Shanghai Talent Development Funding(China).
文摘Identifying potential sources of pharmaceuticals and personal care products(PPCPs)in the environment is critical for the effective control of PPCP contamination.Landfill leachate is an important source of PPCPs in water;however,it has barely been involved in source apportionment due to the lack of indicator-PPCPs(i-PPCPs)in landfill leachates.This study provides the first systematic framework for identifying i-PPCPs for landfill leachates based on the wide-scope target monitoring of PPCPs.The number of target PPCPs increased from<20 in previous studies to 68 in the present study.Fifty-nine PPCPs were detected,with median concentrations in leachate samples ranging from below the method quantification limit(MQL)to 41μg/L,and 19 of them were rarely reported previously.A total of 29 target compounds were determined to be PPCPs of high concern by principal component analysis according to multiple criteria,including occurrence,exposure potential,and ecological effect.Coupled with source-specificity and representativeness analysis,erythromycin,gemfibrozil,and albendazole showed a significant difference in their occurrence in leachate compared to other potential sources(untreated and treated municipal wastewater and livestock wastewater)and correlated with total PPCP concentrations;these were recommended as i-PPCPs for leachates.Indicator screening procedure can be used to develop a sophisticated source apportionment method to identify sources of PPCPs from adjacent landfills.
文摘Rare earth elements(REEs) were extracted from phosphogypsum(PG) using an indirect leaching method that produces CaCO_(3).The carbonation process transforms PG into CaCO_(3),and a potential source of value is the(NH_(4))_(2)SO_(4) fertilizer.The calcium carbonate byproduct is rich in REEs that are originally present in PG.Calcium carbonate,a byproduct of PG carbonation and a rich source of REEs,could dissolve in nitric acid to produce a calcium nitrate leach solution that contains RE nitrate.Subsequently,the most widely used solvent extraction technique can make use of an environmentally benign nitrate ionic liquid.Cyphos IL 101(trihexyl(tetradecyl)phosphonium chloride) is transformed into trihexyl(tetradecyl)phosphonium nitrate([P_(66614)][NO_(3)]) ionic liquid by adding 2.5 mol/L potassium nitrate.The extraction examinations were tested by equilibration of 2 mL of [P_(66614)][NO_(3)] with 2 mL of a synthetic solution of 1000 mg/L of individual La,Ce,and Nd to gain the optimal extraction conditions.The high extraction efficiency of La,Ce,and Nd was gained by stirring a 1/1 aqueous/organic phase ratio and 3 mol/L NH_(4)NO_(3)(as salting out) at 800 r/min for 40 min at 50℃ to decrease the viscosity of [P_(66614)][NO_(3)].The La(Ⅲ),Ce(Ⅲ),and Nd(Ⅲ) stripping efficiencies were examined from their loaded [P_(66614)][NO_(3)] ionic liquid by 1/1 A/O ratio of acidified water,800 r/min stirring speed,and 25℃.After nine cycles,the extraction and stirring efficiency for the La,Ce,and Nd drop to about 80%.The extraction and stripping parameters are applied to the RE leachate from PG to gain the RE oxide with an assay of 92.67%.
基金supported by the National Key Research and Development Program of China(No.2019YFC0408500)the Scientific Research Project of China State Construction Engineering Corporation Limited(CSCEC-2022-K-(36))the Scientific Research Project of CSCEC AECOM Consultants Corporation Limited(XBSZKY2216).
文摘Anaerobic digestion(AD),as an eco-friendly biological process,shows potential for the decomposition of leachate produced by waste incineration power plants.In this study,the effects of Fe oxides nano-modified pumice(FNP)were investigated on the fresh leachate AD process.Firstly,a simple hydrothermal method was used to prepare FNP,then introduced into the UASB reactor to evaluate its AD efficiency.Results showed that the inclusion of FNP could shorten the lag phase by 10 days compared to the control group.Furthermore,cumulative methane production in the FNP group was enhanced by 20.11%.Mechanistic studies suggested that hydrogenotrophic methanogenesis in the FNP group was more pronounced due to the influence of key enzymes(i.e.,dehydrogenase and coenzyme F420).Microbial community analysis demonstrated that FNP could enhance the abundance of Methanosarcina,Proteobacteria,Sytrophomonas,and Limnobacter,which might elevate enzyme activity involved in methane production.These findings suggest that FNP might mediate interspecies electron transfer among these microorganisms,which is essential for efficient leachate treatment.
基金supported by The National Natural Science Foundation of China(No.52262030)Natural Science Research Project of Guizhou Provincial Department of Education(No.[2022]041).
文摘Conventional hydrometallurgy recycling process for treating wasted lithium-ion batteries(LIBs)typically results in the consumption of large amounts of corrosive leachates.Recent research on reusable leachate is expected to significantly improve the economic and environmental benefits,but is usually limited to specific and unique chemical reactions which could only apply to one type of metal elements.Herein,we report the co-extraction of multiple metal elements can be extracted without adding precipitates by mixed crystal co-precipitation,which enables the reusability of the leachate.We show that an oxalic acid(OA):choline chloride(ChCl):ethylene glycol(EG)type DES leachate system can leach transition metals from wasted LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)(NCM)cathode materials with satisfactory efficiency(The time required for complete leaching at 120℃ is 1.5 h).The transition metals were then efficiently extracted(with a recovery efficiency of over 96%for all elements)by directly adding water without precipitants.Noteworthy,the leachate can be efficiently recovered by directly evaporating the added water.The successful realization of reusability of leachate for the synergistic extraction of multiple elements relies on the regulation of the mixed crystal co-precipitation coefficient,which is realized by rationally design the reaction condition(composition of leachate,temperature and time)and induces the extraction of originally soluble manganese element.Our strategy is expected to be generally applicable and highly competent for industrial applications.
基金financially supported by the National Natural Science Foundation of China(Grant No.52078142).
文摘Leachate sludge,a byproduct of municipal solid waste leachate treated through biochemical processes,is characterized by high water content(761.1%)and significant organic matter content(71.2%).Cement that is commonly used for solidifying leachate sludge has shown limited effectiveness.To address this issue,an alkali-activated ground-granulated blast-furnace slag(GGBS)geopolymer blended with polypropylene fibers was developed to solidify leachate sludge.Moreover,unconfined compressive strength(UCS),immersion,as well as X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and scanning electron microscope(SEM)tests were conducted to investigate the solidification effect and mechanism of the GGBS-based geopolymer and fibers on leachate sludge.The results showed that:the 28-d UCS of the solidified sludge with 20%and 30%GGBS is 0.35 MPa and 1.85 MPa,and decreases to 0.18 MPa and 1.13 MPa,respectively,after soaked in water for 28 d.Notably,the UCS of the solidified sludge with 30%GGBS satisfied the strength requirement of roadbed materials.Polypropylene fibers significantly enhanced the strength,ductility and water stability of the solidified sludge,with an optimal fiber content of 0.3%.Alkali-activated GGBS geopolymer generated three-dimensional,cross-linked geopolymeric gels within the solidified sludge,cementing sludge particles and filling intergranular pores to form a stable cementitious structure,thereby achieving effective solidification.Furthermore,incorporating polypropylene fibers improved the bonding and anchoring effect between fiber and solidified sludge,constrained lateral deformation of the solidified sludge,restricted crack propagation,and enhanced engineering performance of the solidified leachate sludge.
基金supported by the National Key Re-search and Development Project of China(No.2023YFC3108400).
文摘Bioremediation has gained significant attention due to its potential to remove azo dyes.However,the challenges microor-ganisms face in surviving when azo dyes are the sole carbon source limit its widespread application.This study aimed to improve the biodegradation of azo dyes by utilizing Baijiu distiller’s grains leachate(BDGL)as a co-substrate.The experimental results demon-strated that BDGL significantly enhanced Providencia rettgeri’s ability to degrade the model pollutant Acid Black 210(AB210),achieving a decolorization efficiency of 94.5%.This may be attributed to the nutrient-rich composition of BDGL,which includes ethanol and protein,providing a favorable substrate for bacterial growth and activity.The higher biomass and increased activities of azoreductase and quinone oxidoreductase in the BDGL group further supported these findings.Additionally,this method demonstra-ted broad-spectrum degradation of azo dyes(Direct Red 5B,Acid Red 73,and Congo Red)with different structures,highlighting its potential applicability.Metabolite assays combined with transcriptomics analyses revealed that the expression of functional genes re-lated to redox reactions,azo bond cleavage,and hydrolysis increased under the co-metabolic conditions of BDGL,resulting in stronger reducing power that further mineralized the dye into smaller metabolites.Our study offers a practical strategy for the simulta-neous treatment of dye-containing wastewater and Baijiu distiller’s grains,with significant environmental and industrial applications.
基金jointly supported by a project of the China Geological Survey(DD20243375)Hebei Key Laboratory of Mineral Resources and Ecological Environment Monitoring(No.HBMREEM202403).
文摘Antibiotics,as emerging pollutants,pose significant risks to aquatic ecosystems and human health by disrupting the endocrine systems of aquatic organisms and affecting ecosystem stability through food chain enrichment.In a study conducted in Hebei Province,China,liquid chromatography-triple quadrupole-linear ion trap mass spectrometry(LC-TQ-LIT-MS)was used to analyze 90 different antibiotics in 31 water samples,including surface water,groundwater,and waste leachate from three urban landfills.This analysis included hormones,broad-spectrum antimicrobials,macrolides,tetracyclines,β-lactams,sulfonamides,and quinolones.The study’s results indicated that quinolones,β-lactams,and macrolides were the most frequently detected substances in the landfills.It is noteworthy that the concentrations of these antibiotics varied significantly among different cities,reflecting local production and living characteristics.The results of the tests showed that the concentration of amoxicillin was 1171 ng/L in surface water,811 ng/L in groundwater,and 1926 ng/L of ciprofloxacin in waste leachate.Furthermore,a consistent pattern was observed between the compounds present in the leachate,groundwater,and surface water at the three sites.Risk assessments revealed that the ecological risk was higher for surface water and lower for groundwater.This study is the first to systematically analyze the pollution status of antibiotics and hormones in the water around the landfill in Hebei Province,which not only fills the blank of groundwater-related research in Hebei Province but also provides key data support and theoretical basis for local groundwater hydrological and environmental detection and pollution prevention.
基金supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (2023R1A2C100571511,RS-2023-00254424)the Ministry of Education(2020R1A6A1A03038540)。
文摘As the global electric vehicle market continues to grow,the recycling of Li-ion battery (LIB) becomes more important worldwide and the resynthesis of cathode materials would be the most value-added recycling approach taking into account limited metal resources.Although resynthesized homogenous LiNi_(x)Co_(y)Mn_(z)O_(2)(NCM) from spent LIB leachate shows comparable battery performance to pristine NCM from virgin materials,there is general concern in its cycling performance.Here,we synthesize core–shell(CS) Ni-rich NCM,which consists of Ni-rich NCM as the core and NCM derived from the original or purified leachate of spent LIBs as the shell.Resynthesized CS Ni-rich NCM exhibits improved rate capability resulting from expanded interslab thickness in the NCM structure.CS Ni-rich NCM from purified LIB leachate shows improvement in cycling performance and thermal stability.It specifically delivers a capacity retention of 86.6%at a high temperature after 80 cycles compared to that (75.0%) of pristine CS Ni-rich NCM.These improvements are caused by a relatively high Mg content on the shell and the widespread distribution of Al through the CS structure.CS Ni-rich NCM derived from spent LIB leachate provides a new alternative approach to conventional LIB recycling methods,which would utilize efficiently limited metal resources for the sustainable LIB production.
基金This work was supported by the Natural Science Foundation of China(No.51938010)the Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment(No.XTCXSZ2022-1).
文摘Humic acid(HA)is a typical refractory organicmatter,so it is of great significance to investigate its effect on the performance of Anammox granular sludge.When the dosage ofHA≤50 mg/L,HA promotes the total nitrogen removal rate(NRR)to 1.45 kg/(m^(3)·day).When HA was between 50 and 100 mg/L,the NRR of Anammox was stable.At this time,the adsorption of HA causes the sludge to gradually turn fromred to brown,but the activities of heme and enzymes showed that its capacitywas not affected.When HA levels reached 250 mg/L,the NRR dropped to 0.11 kg/(m^(3)·day).Moderate HA levels promoted the release of extracellular polymeric substance(EPS),but excessive HA levels lead to a decrease in EPS concentrations.HA inhibited Anammox activity,which indirectly hindered the transmission of substrate and accumulated substrate toxicity.Although HA promoted the increase of heterotrophicmicrobial abundance in Anammox system,the microbial diversity decreased gradually.With the increase of HA concentration,the abundance of Candidatus_Brocadia,the main functional microorganism of Anammox system,decreased gradually,while the abundance of Candidatus_Kuenenia increased gradually.
文摘Groundwater contamination near landfills is commonly caused by leachate leakage,and permeable reactive barriers(PRBs)are widely used for groundwater remediation.However,the deactivation and blockage of the reactive medium in PRBs limit their long-term effectiveness.In the current study,a new methodology was proposed for the in situ regeneration of PRB to remediate leachate-contaminated groundwater.CO_(2)coupled with oxidants was applied for the dispersion and regeneration of the fillers;by injecting CO_(2)to disperse the fillers,the permeability of the PRB was increased and the oxidants could flow evenly into the PRB.The results indicate that the optimumfiller proportion was zero-valent iron(ZVI)/zeolites/activated carbon(AC)=3:8:10 and the optimum oxidant proportion was COD/Na_(2)S_(2)O_(8)/H_(2)O_(2)/Fe^(2+)=1:5:6:5;the oxidation system of Fe^(2+)/H_(2)O_(2)/S_(2)O_(8)^(2−)has a high oxidation efficiency and persistence.The average regeneration rate of zeolites was 72.71%,and the average regeneration rate of AC was 68.40%;the permeability of PRB also increased.This technology is effective for the remediation of landfills in China that have large contaminated areas,an uneven pollutant concentration distribution,and a long pollution duration.The purification mode of long-term adsorption and short-time in situ oxidation can be applied to the remediation of long-term high-concentration organically polluted groundwater,where pollution sources are difficult to cut off.