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Treatment of landfill leachate by ozonation-biological aerated filter process

Wang Kaiyan,Wang Xiaojun,Liu Jianyu,

环境工程学报 , 2009,
Abstract: The combining process of ozonation and biological aerated filter(BAF) was used in the advanced treatment of landfill leachate after common treatment.The biodegradability of the organic pollutants of landfill leachate was improved after ozonation.Color of the wastewater reduced markedly after the ozonation.Ozonation was really a favorable means for wastewater treatment.Then biological aerated filter was adopted as the further treatment,COD of the effluent could be lower than 100 mg/L,which met the national f...
Biological Treatment of Landfill Leachate Using Sea Water Microflora Under Aerobic and Anaerobic Conditions
International Journal of Biological Engineering , 2012, DOI: 10.5923/j.ijbe.20120205.01
Abstract: The present study demonstrates an appropriate technique for treatment of landfill leachate. Pretreatment with alum and anionic poly electrolyte as coagulant and flocculent materials caused 43% reduction of COD. Sucrose and nutrient broth were used for enrichment of sea water microflora. The pretreated leachate was used for determination of aerobic and anaerobic biological treatments of sea water enriched microflora. BOD5, COD and TSS reduction were acquired in best samples 90.3%, 95.1% and 44.8% in aerobic and 31.2%, 38.3% and 37.3% in anaerobic conditions, respectively. The metal removal was determined in aerobic and anaerobic treatments and up to 90% metal removal acquired in some cases.
Municipal Leachate Treatment by Fenton Process: Effect of Some Variable and Kinetics  [PDF]
Mohammad Ahmadian,Sohyla Reshadat,Nader Yousefi,Seyed Hamed Mirhossieni,Mohammad Reza Zare,Seyed Ramin Ghasemi,Nader Rajabi Gilan,Razieh Khamutian,Ali Fatehizadeh
Journal of Environmental and Public Health , 2013, DOI: 10.1155/2013/169682
Abstract: Due to complex composition of leachate, the comprehensive leachate treatment methods have been not demonstrated. Moreover, the improper management of leachate can lead to many environmental problems. The aim of this study was application of Fenton process for decreasing the major pollutants of landfill leachate on Kermanshah city. The leachate was collected from Kermanshah landfill site and treated by Fenton process. The effect of various parameters including solution pH, Fe2+ and H2O2 dosage, Fe2+/H2O2 molar ratio, and reaction time was investigated. The result showed that with increasing Fe2+ and H2O2 dosage, Fe2+/H2O2 molar ratio, and reaction time, the COD, TOC, TSS, and color removal increased. The maximum COD, TOC, TSS, and color removal were obtained at low pH (pH: 3). The kinetic data were analyzed in term of zero-order, first-order, and second-order expressions. First-order kinetic model described the removal of COD, TOC, TSS, and color from leachate better than two other kinetic models. In spite of extremely difficulty of leachate treatment, the previous results seem rather encouraging on the application of Fenton’s oxidation. 1. Introduction In the past decades, industrial growth and technology development lead to the increasing solid waste production [1]. According to the World Health Organization studies, in the many countries such as France, Canada, America, Norway, England, Spain, and Italy, sanitary landfilling had been recognized as the common, economic and acceptable method for solid waste disposal [2–4]. Landfill leachate is a complex waste matter, which usually causes adverse effects in the environment [5, 6]. The leachate characteristics are depended on the type of solid waste, soil properties, rainfall patterns, and age of landfill site. The concentration of nonbiodegradable and resistant materials with high molecular weight such as humic and fulvic acid arises with increase of the landfill site age [7]. Due to variable characteristic of landfill leachate, the coherent method for leachate treatment was not developed [8]. The concerning of solid waste leachate may be related to presence of heavy metals and nonbiodegradable organic materials in solid waste leachate and its adverse effects on human and the environment [3]. Application of biological treatment processes (as dominant treatment) cannot remove nonbiodegradable organic materials and additional treatments are required for leachate treatment [9]. Biological treatment processes are suitable for fresh leachate with high ratio of BOD5/COD but cannot be applied in the treatment
Variability of Parameters Involved in Leachate Pollution Index and Determination of LPI from Four Landfills in Malaysia  [PDF]
Muhammad Umar,Hamidi Abdul Aziz,Mohd Suffian Yusoff
International Journal of Chemical Engineering , 2010, DOI: 10.1155/2010/747953
Abstract: Landfill sites are potential sources of human and environmental hazards. Leachate produced form these waste dumping sites is heterogeneous and exhibits huge temporal and seasonal variations. Leachate pollution index (LPI) provides an overall pollution potential of a landfill site. The parameters required to calculate LPI from a landfill site are discussed in terms of their variations over time, and their significance has been highlighted in the context of LPI. The LPI values of two semiaerobic and two anaerobic landfill sites in Malaysia have been calculated in this study. Pulau Burung Landfill Site (PBLS) was found to have the highest LPI score while Ampang Jajar Landfill Site (AJLS) showed the lowest LPI as compared to other landfills. It is concluded that LPI value can be used as a tool to assess the leachate pollution potential from landfill sites particularly at places where there is a high risk of leachate migration and pollution of groundwater. 1. Introduction Landfills are the primary means of municipal solid waste (MSW) disposal in many countries worldwide because they offer dumping high quantities of MSW at economical costs in comparison to other disposal methods such as incineration. Landfill leachate produced form MSW landfill sites is generally heavily contaminated and consist of complex wastewater that is very difficult to deal with [1–4]. The generation of leachate is a result of percolation of precipitation through open landfill or through cap of the completed site [5]. Leachate is characterized by high concentration of organic matter (biodegradable and non-biodegradable), ammonia nitrogen, heavy metals, and chlorinated organic and inorganic salts [6]. The characteristics of leachate are highly variable [7] depending on the waste composition [2], amount of precipitation, site hydrology, waste compaction, cover design, sampling procedures, and interaction of leachate with the environment, landfill design and operation [8]. Organic content of leachate pollution is generally measured in terms of biological oxygen demand (BOD5) and chemical oxygen demand (COD). The concentrations of leachate contaminants may range over several orders of magnitude [9]. A combination of pollutants (BOD5, COD, ammonia, inorganic salts, etc.) in higher concentrations renders landfill leachate as a potential source of contamination both to ground and surface waters, hence necessitates its treatment prior to discharge to water resources [10]. The management of leachate is among the most important factors to be considered in planning, designing, operation, and
Potential of Ceria-Based Catalysts for the Oxidation of Landfill Leachate by Heterogeneous Fenton Process  [PDF]
E. Aneggi,V. Cabbai,A. Trovarelli,D. Goi
International Journal of Photoenergy , 2012, DOI: 10.1155/2012/694721
Abstract: In this study, ceria and ceria-zirconia solid solutions were tested as catalyst for the treatment of landfill leachate with a Fenton-like process. The catalysts considered in this work were pure ceria and ceria-zirconia solid solutions as well as iron-doped samples. All the catalysts were extensively characterized and applied in batch Fenton-like reactions by a close batch system, the COD (chemical oxygen demand) and TOC (total organic carbon) parameters were carried out before and after the treatments in order to assay oxidative abatement. Results show a measurable improvement of the TOC and COD abatement using ceria-based catalysts in Fenton-like process and the best result was achieved for iron-doped ceria-zirconia solid solution. Our outcomes point out that heterogeneous Fenton technique could be effectively used for the treatment of landfill leachate and it is worth to be the object of further investigations. 1. Introduction Landfill leachate is a liquid waste of primary environmental concern because of the quantity and quality of the harmful pollutants contained in it. There are a large number of various types of organic and inorganic substances, depending on the age and type of solid wastes located in the landfill. Leachate from sanitary landfills can be an important source of ground water contamination and for this reason it is collected from the bottom of the landfill to be treated; further, this highly contaminated liquid waste accumulates a great diversity of harmful pollutants. Some of them are particularly refractory and for this reason traditional wastewater treatment plants are not efficient in their abatement. Inorganic and organic content of leachate is characteristically related to environmental risk because of scarce biodegradation, severe bioaccumulation, and potential health damages [1, 2]. It is well known that conventional biological liquid waste treatments alone are unable to achieved complete removal of the leachate pollution over the life of the landfill. In truth conventional biological processes are time consuming and low-efficiency methods to treat directly leachate, consequently physicochemical processes are frequently utilized to pretreat this liquid waste in order to reduce organic refractory before biological action in treatment plants units [3]. The most employed and studied methods in landfill leachate pretreatment are chemical or electrochemical coagulation [4], precipitation [5], and oxidation [6, 7]. Among these, a particular attention is given to oxidation techniques and especially to advanced oxidation processes
Pilot Scale Research on Impacts of Leachate Recirculation on Its Ultimate Treatment

DENG Zhou,JIANG Jian-guo,HUANG Zhong-lin,FENG Xiang-ming,ZHOU Sheng-yong,YANG Guo-dong,

环境科学 , 2006,
Abstract: Two pilot scale simulated columns,with and without leachate recirculation,were erected to study impacts of leachate recirculation of traditional anaerobic bioreactor landfill on leachate ultimate treatment methods.The results indicate that recirculation can remove organic pollutants visibly,but it isn't effective to inbiodegradable components,nitrogen(N) and phosphorus(P) pollutants.After recircualted for 44 weeks,test column has a BOD5 removal ratio of 98.5%.BOD5/COD value of outflow is only 0.07.BOD5/TN and BOD5/TP are 0.13 and 11 respectively,which are much lower than the adequate value for anaerobic microorganisms.It's difficult to treat this kind of leachate by traditional biological methods.When a bioreactor landfill is being designed,leachate characteristics after recirculated should be well considered and adequate leachate treatment,landfill and recirculation schemes should be chosen to take full advantage of waste stack decontamination effects.
Landfill leachate treatment in assisted landfill bioreactor
HE Pin-jing,QU Xian,SHAO Li-ming,LEE Duu-jong,
HE Pin-jing
,QU Xian,SHAO Li-ming,LEE Duu-jong

环境科学学报(英文版) , 2006,
Abstract: Landfill is the major disposal route of municipal solid waste(MSW) in most Asian countries. Leachate from landfill presents a strong wastewater that needs intensive treatment before discharge. Direct recycling was proposed as an effective alternative for
Study the Efficiency of the Combined System of Coagulation and Flocculation/Ozonation in Treatment of Fresh Landfill Leachates in Tabriz City
A Taghipour,A.H Mahvi,R Nabizade,R Dehghanzade
Iranian Journal of Health and Environment , 2011,
Abstract: "nBackground and Objectives: Fresh leachate has a low pH and high amounts of BOD and COD which are mainly constituents with low weight molecular such as volatile fatty acids ( acetic and propionic acids) .Management and treatment of leachate is an important subject in sanitary landfill operation and performance.Th objective of this study is determining the efficiency of the integrated coagulation -flocculation and ozonation processes in fresh leachate treatment of Tabriz city."nMaterials and Methods: Quantitive parameters of pH, BOD5, COD , alkalinity and TSS were studied based on standard methods.The study emphasizes of COD and TSS leachate removal.Alum , ferric chloride and PAC had been used as coagulants."nResults : Results indicated the superiority of Ferric chloride at the dosage of 1 g/l in pH 10 ,whichreduced 34% of COD and 54% of TSS.in the stage of ozonation the leachate sample coagulated by ferric chloride was treated by 3 g/h ozone gas at optimum pH and after 39 hours ozonation about 51% of COD and 18.2 % of TSS were reduced."nConclusion: This study clearly indicates that there would be need to apply biological treatment (after coagulation - flocculation ) and ozonation , various advanced oxidation processes and / or other treatment methods for further reduction of COD in leachate and meeting discharge standards.
The Study on Biodegradability Enhancement of Landfill Leachate by Fenton Oxidation
M Farrokhi,M Kouti,Gh.R Mousavi,A Takdastan
Iranian Journal of Health and Environment , 2009,
Abstract: "n "n "nBackgrounds and Objectives: Leachate is one of the landfill products and also a wastewaterbearing the most advers effects on the environment. Biological methods are usually employed for treatment of young leachate (1-2 years) wich is of high concentration of organic compounds with low molecular weight. However these methods are not approprate for mature leachate (5-10years) due to having high rate of compounds with molecular weight and the presence of materials resistant to biodegradation and toxic compounds . Advanced oxidation process such as Fenton reagent used in treatment or biodegrability improvement of strong wastewater. In the present study the degrability improvement of mature leachate through oxidation fenton process in bench scale and in batch reactorhas been investigated."nMaterials and Methods: The samples have been taken from Ahwaz landfill and factors such as initial COD and BOD, pH, BOD5/COD were studies as degradability, the amount of Hydrogen Peroxide, Fe(II), optimal reaction time and optimal pH."nResults:The highest amount of COD removal was observed in PH=3-3.5 and 90 minutes of reaction time. H2O2=29700mg/land Fe2+=16500 mg/l in [Fe2+]/[H2O2]=1/14.8 molarity ratio were obtained as optimal amounts BOD5/COD was equal to 0.38."nConclusion: This study indicates that Fenton oxidation enhances the biodegradability of leachate.
Comparison of Diffrent Coagulants Efficiency for Treatment of Hamedan Landfills Leachate Site
M.T Samadi,M. H Saghi,M. Shirzad,S. Rahimi
Iranian Journal of Health and Environment , 2010,
Abstract: "n "n "nBackgrounds and Objectives:In Iran , indicated that the municipal landfill leachate has been one of the major problem for environment. In the operations, leachate treatment is a very difficult and expensive process. Although, young leachate can be treated easily by biological treatment, COD removal efficiency are usually low due to high ammonium ion content and the presence of toxic compounds such as metal ions. Treatment of leachate is necessary.The aim of this study is reduction of Chemical Oxygen Demond (COD) and Total Suspended Solids (TSS) from hamedan city sanitary landfill leachate by three coagulants: alum, PAC and ferrous sulfate."nMaterials and Methods: This experimental study was conducted to investigate the effect of treatment of landfill leachate by a coagulation-flocculation process. The effects of different amounts of coagulant and different pH values on the coagulation processes were compared."nResults:Result shown the high efficiency for reduction of CODby PAC in pH=12 and concentration of 2500(mg/l (62.66%), and by alum in pH=12 and concentration of 1000 (mg/l) (60%) , by ferrous sulfate in pH=2 and concentration of 1000 (mg/l) (70.62%). Also result shown the high efficiency for TSS removal by PAC in pH=12 and 2500(mg/l) concentration of PAC was 58.37%, with alum in pH=2 and 1500 (mg/l) concentration of alum was39.14% , by ferrous sulfate in pH=7 and 2500(mg/l) concentration of ferrous sulfate was 35.58%."nConclusion:The best coagulant for COD removal is ferrous sulfate.The physico-chemical process may be used as a useful pretreatment step, especially for fresh leachates, prior to post-treatment (polishing) step for partially stabilized leachates.
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