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Method of MSW landfill reclamation using waste conversion products
Published in Vladimir Litvinenko, Advances in Raw Material Industries for Sustainable Development Goals, 2020
N.O. Milyutina, N.A. Averianova, E.S. Velikoselsksya, D.M. Malyuhin, N.A. Politaeva
The main methods for purifying the leachate can be divided into biological (aerobic and anaerobic), mechanical (sedimentation, filtration, separation) and physicochemical (coagulation, flocculation, flotation, ion exchange, sorption, micro and ultrafiltration, reverse osmosis, ozonation, electrolysis, ultraviolet radiation) (Henze, 1995, Renou, 2008, Salem et al., 2008, Silva, 2004, Trebouet, 2001). To achieve a high degree of purification, a combination of these methods is necessary. The most commonly used technology nowadays is reverse osmosis with preliminary mechanical and/or physicochemical treatment of the leachate. The permeate (purified water) obtained as a result of such a purification scheme corresponds to the quality required for its discharge to surface water (Renou, 2008). On the other hand, the use of reverse osmosis leads to the formation of a concentrate representing 25-50% of the raw leachate, which is itself a new form of waste that must be disposed of.
Landfill Leachate Treatment
Published in Eric Senior, Microbiology of Landfill Sites, 2020
Leachate is a complex organic liquid formed primarily by the percolation of precipitation water through the open landfill or through the cap of the completed site. To a lesser extent, leachate can be formed as a result of the initial moisture content of the waste.6 The resulting leachate is a complex and highly variable mixture of soluble organic, inorganic, bacteriological constituents and suspended solids in an aqueous medium. Since all organic materials in the waste undergo partial or total microbial decomposition (mineralization), all leachates contain intermediate products together with high concentrations of toxic organics, heavy metals, and other xenobiotic materials. The exact composition is variable and site specific depending on the type and age of refuse and the amount of precipitation. It is apparent that the leachate quality and composition7 can vary so widely that attempts to define a typical leachate must include such broad concentration ranges of the different contaminants as to be virtually meaningless for treatability studies.8
Contaminant Pathways — Subsurface Investigation and Monitoring Approach
Published in Christopher M. Palmer, Principles of Contaminant Hydrogeology, 2019
Mixers are contaminant chemistries, and solubilities may allow for mixing (or without some preferential partitioning) through the aquifer. This type of contaminant plume may become distributed into relatively uniform concentrations once the plume has moved away from the source. A contaminant may have some preferential partitioning, but if large quantities are released, or it has been in the aquifer for a long period, concentrations may become somewhat evenly distributed. Municipal landfill leachate is generated from any landfill, past or present. Leachate may contain nearly any contaminant prior to stricter regulation and even now, anything could have been disposed in a domestic refuse landfill (hazardous waste landfills and impoundments may differ). The leachate as a rule tends to be acidic and may contain both metals and traces of various organic compounds from household and light industrial containers. Studies have observed the leachate migrating from the fill to aquifers, and a relatively uniform concentration distribution usually occurs (Gillham and Cherry, 1982). Recent work by Bjerg et al. (1995) shows that different areas of redox zones can exist in leachate and affect contaminant movement and attenuation processes (see Figures 9 and 10).
Cr, Ni, and Zn removal from landfill leachate using vertical flow wetlands planted with Typha domingensis and Canna indica
Published in International Journal of Phytoremediation, 2022
María Alejandra Maine, Hernán Ricardo Hadad, Nahuel Ernesto Camaño Silvestrini, Emanuel Nocetti, Gabriela Cristina Sanchez, Marcelo Abel Campagnoli
Leachate is generated as rainfall percolates through solid waste in a landfill cell. Even when the landfill ceases to receive waste and is covered with topsoil, leachate will continue to be generated for decades. Landfill leachate contains a wide range of contaminants in concentrations that vary over time (Kadlec and Wallace 2009). The expected volume and chemical quality of landfill leachate are highly site-specific because of climate conditions, and leachate varies significantly depending on waste nature, landfill age, and landfilling technology ( Kjeldsen et al. 2002; Kadlec and Wallace 2009). As an example, metal concentrations in leachates of closed or old landfills are normally lower than those of young landfills (Öman and Junestedt 2008). It was reported that a typical composition of leachate was characterized by biological oxygen (O2) demand (BOD): 20–20,000mg L−1 O2, chemical oxygen demand (COD): 40–90,000mg L−1 O2, ammonium- nitrogen (NH4+-N): 0.01–1,900mg L−1, total Kjeldahl N (TKN): 70–1,900 mg L−1, and heavy metals such as cadmium (Cd): 0.005–8.2mg L−1, chromium (Cr): 0.001–208mg L−1, lead (Pb): 1–19mg L−1, nickel (Ni): 0.03–3.2mg L−1, and zinc (Zn): 0.00005–120mg L−1 (Baun and Christensen 2004; Öman and Junestedt 2008; Kadlec and Wallace 2009).
Evaluation of beneficial of polyacrylamide use dewatering of dredged sludge obtained from golden horn
Published in Marine Georesources & Geotechnology, 2021
Ümit Karadoğan, Sevde Korkut, Gökhan Çevikbilen, Berrak Teymur, İsmail Koyuncu
It is believed that the improper and uncontrolled use of synthetic polyacrylamide, which can play an effective role in the dewatering studies with geotextiles, can cause harmful consequences to the health and environment (Glover et al. 2004; McLaughlin and Bartholomew 2007; Semsar, Scholz, and Kulicke 2007). The limited number of polymers used in pilot experiments brings the risk of using a low suitable polymer at a high dosage. If the environmental factors are considered, it is obvious that detailed research is necessary for selecting the appropriate polymer and determining the optimum dosage. In the dewatering implementations, if the polymer dosage is more than needed, the free polymer remains in the leachate at a level causing the flocculation in the receiving body. One the other hand, if the polymer dosage is less than needed, the amount of solids increases in the leachate in the receiving environment. Moreover, the quality of leachate should meet the limit values specified in the regulations for the receiving body. These two criteria are critical for an effective dewatering implementation. Accordingly, conducting more extensive preliminary research will be beneficial both environmentally and economically.
Towards advanced nitrogen removal and optimal energy recovery from leachate: A critical review of anammox-based processes
Published in Critical Reviews in Environmental Science and Technology, 2020
Jiongjiong Ye, Jianyong Liu, Min Ye, Xiao Ma, Yu-You Li
Leachate, which is produced in compost sites and sanitary landfills can contaminate groundwater and affect the quality of surface and well waters (Mukherjee, Mukhopadhyay, Hashim, & Sen Gupta, 2015; Roy, Azais, Benkaraache, Drogui, & Tyagi, 2018). As shown in Table 1, a wide range of leachate compositions have been reported in the literature. In general, high concentrations of nitrogen and organics are the primary pollutants in leachate and pose key difficulties in leachate treatment (Berge, Reinhart, & Townsend, 2005; Renou, Givaudan, Poulain, Dirassouyan, & Moulin, 2008). At the same time, high levels of Ca2+ and Mg2+ in leachate are known to result in serious fouling problems in treatment facilities. The characteristic variations of landfill leachate with landfill age are listed in Table 2. The characteristics of fresh landfill leachate are similar to those of compost and incineration leachate, with high COD concentrations and a high BOD/COD ratio. Although the ammonium concentration in fresh landfill leachate is always below 400 mg/L (Table 2), it is much higher (1000–3000 mg/L) after anaerobic digestion.