This research explores the use of UV absorption and fluorescence spectroscopy for rapid monitoring of organic compounds in leachates and performs a systematic comparison of the biodegradation associated evolution of different organic compounds of leachates collected from two UK MSW landfills L1 and L2. Spectroscopic techniques are used to characterize the aromatic compounds and to study the evolution of humic, fulvic and protein like compounds which is compared with the well established organic strength estimation techniques dissolved organic carbon (DOC) and chemical oxygen demand (COD). The biodegradation of different leachates as estimated from the reduction of different organic compounds using spectroscopy show an excellent agreement with the biodegradability assessed by the conventional methods DOC and COD indicating that characterization of landfill leachates using spectroscopic methods are reliable. It is also found that leachates collected from treatment plant and phase 4 of landfill L1 (L1 (LTP) and L1 (P4) respectively) and phase 2 of landfill L2 (L2 (P2)) are less biodegradable and contain aromatic ring of more condensed form than those for leachates collected from treatment plant of landfill L2 (L2 (LTP) and L2 (FE)) which indicate a relatively rigorous treatment requirement for L1 (LTP), L1 (P4) and L2 (P2) leachates to meet the effluent standard.

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This study investigates the use of UV absorption and fluorescence spectroscopy to assess the early development of recalcitrant organic compounds in leachates formed during the anaerobic biodegradation of municipal solid waste. Biochemical methane potential tests were carried out on fresh waste (FW) and composted waste (CW) over a period of 150 days and leachates produced from the degradation of two wastes were analysed for humic-like (H-L) and fulvic-like (F-L) structures by UV spectroscopy and fluorescence excitation-emission-matrix analyses. During anaerobic biodegradation, the synthesis and utilization of H-L and F-L structures in the leachates over time was indicative of the generation of the recalcitrant organic compounds. The results obtained from UV absorption and fluorescence spectroscopy suggested that CW leachates resulted in a higher concentration and more condensed form of recalcitrant H-L and F-L molecules than FW leachates. These findings demonstrate how fluorescence and UV absorption spectroscopy can be used as an indicator for monitoring the evolution of recalcitrant organic compounds (H-L and F-L substances) in leachates formed at different stages of waste biodegradation.

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This study investigated the use of ultraviolet (UV) and fluorescence spectroscopy to monitor the changes in biodegradability of dissolved organic matter (DOM) in landfill leachates. Experiments to investigate aerobic biodegradation of leachate DOM were carried out using untreated and treated leachate samples collected from two UK municipal solid waste landfills, L1 and L2.Leachate samples collected at different stages of the aerobic treatment processes were characterized by conventional methods (chemical oxygen demand (COD) and dissolved organic carbon content (DOC)) and also by UV spectroscopy and fluorescence excitation-emission matrix.The laboratory-scale aerobic treatment system achieved reductions in COD and DOC in all of the leachates. Results obtained from UV spectrophotometry indicated that the aromatic character of the leachate decreased during aerobic biodegradation. Additionally, the fluorescence intensity of the leachates decreased to various extents, suggesting degradation of humic, fulvic or proteinlike structures during biodegradation. Initial results showed strong relations between fluorescent DOC and fluorescent COD and suggest that the strength of these correlations could be a useful tool in distinguishing sources and biodegradability of DOC cheaply and quickly, although further research using different types of leachates is required.

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