Impacts of temperature and liquid/solid ratio on anaerobic degradation of municipal solid waste: an emission investigation of landfill simulation reactors

Abstract

Management of landfi ll emissions, i.e., landfi ll gas (LFG) and landfi ll leachate, is an important and resourceintensive task. A long-term demonstration pilot, consisting of landfi ll simulation reactors (LSRs), was used to study the impact of temperature and the applied liquid/solid ratio (L/S ratio) on landfi ll emissions, characteristics, and trends. This pilot has already run for more than 1000 days since the end of 2004 and will continue to run for some time. The degradation of waste at different temperatures has impacts on the overall degradation degree and on the length of postclosure care required. Higher temperatures accelerated the degradation, but also resulted in higher leachate chemical oxygen demand (COD) and ammonia concentrations, which prolong the aftercare period. Meanwhile, at a given stabilization degree [e.g., 70 l gas/kg waste (dry)], the total leached nitrogen under psychrophilic conditions was 3.5 times that under mesophilic/thermophilic conditions, which resulted in a higher required effort for leachate treatment. The impact of L/S ratio or simulated annual L/S rates was also evaluated. The results show the signifi cance of efficiently obtaining the targeted L/S ratio in order to achieve low landfi ll emission potential.

Statistical modelling and assessment of landfill leachate emission from fresh municipal solid waste: A laboratory-scale anaerobic landfill simulation reactor study

“…EC is influenced by the amount of dissolved organic and inorganic matter present in the leachate, and used to indicate the degree of salinity and mineral content. EC values ranged from 5.05 to 16.28 mS cm -1 due to the production of carbonates and bicarbonates as a result of high biological activity (Wang and Pelkonen, 2009). The values were found to be similar to the reported values during the acidogenic phase (1.6-17 mS cm -1 ) (Reinhart and Grosh, 1998).…”

“…The literature reports that VFA greater than 10000 mg L −1 is toxic to methanogenic activity and that the pH should be in the range of 6-8 (Petchsri et al, 2006). A high VFA content is expected, as acid production is enhanced if the moisture content of the solid waste is high (Wang et al, 2009). Solids (total solids, total dissolved solids, total suspended solids, total fixed solids and total volatile solids).…”

Effects of Temperature on the Long-Term Behaviour of Waste Degradation, Emissions and Post-Closure Management Based on Landfill Simulators

“…Landfill simulators (LSRs) are primarily applied to obtain a more realistic picture of waste degradation and leaching and optimise waste stabilisation in order to shorten the aftercare time. By significantly higher water application in the anaerobic or aerobic LSR tests, long-term development of leachate quality and gas generation can be rather quickly simulated [15][16][17][18] or more selectively the impact of temperature [19].…”

Pattern of Characteristics of Leachate Generation from Municipal Solid Waste Landfill by Lysimeter Experiment

“…Compared meshophilic conditions and psychophilic, landfill with high ambient temperatures (thermophilic) would increase the rate of waste degradation marked the high COD concentration [8]. Constituents in the leachate change quite large between the landfill by recirculation and landfill without recirculation [9].…”