Advanced Monitoring and Control of Anaerobic Digestion in Bioreactor Landfills

Abstract

Additional information is available at the end of the chapter http://dx.doi.org/10.5772/55715 . IntroductionDespite recent increases in recycling, composting, and incineration, the sanitary landfill remains the predominant and most economical municipal solid waste MSW management alternative. Modern MSW landfills strive to optimize the design, construction, and operation processes in order to mitigate many of the potentially negative impacts, and improve the profitability. The bioreactor landfill "L is considered one of the promising developments that have recently gained significant attention. This waste-to-energy technology requires specific management activities and operational procedures that enhance the microbial decomposition processes inside the landfill resulting in higher production of landfill gas [ ]. The recirculation of leachate, which is conducted by recycling the water passing through and collected from the landfill, is considered the main operational characteristic in the "L to increase moisture, and consequently stimulate the biodegradation process Figure . The potential benefits of the "L include increased waste settlement rates and airspace utilization, decreased costs for leachate treatment, more rapid gas production which improves the economics of gas recovery , and more rapid waste stabilization which may reduce the post-closure maintenance period . These potential benefits have led to many full-scale "L applications in the last decade, mostly in the United States, resulting in the generation of design and operation data. In , the Solid Waste "ssociation of North "merica conducted an inventory that identified over "Ls in North "merica [ ]. Many of these experiences revealed scale-up issues and technical limitations that merit further research and development [ -].One of the most critical, yet little studied, issues in the operation of "Ls is process control. In field applications, unsupervised operational procedures can disturb the dynamics of the landfill biological processes causing serious consequences on the overall evolution of the ecosystem, i.e., unstable and sometimes unsuccessful transition from one operational phase to

Characterization of leachate produced by a landfill and its influence on a sewage treatment plant

“…In the stabilized leachates, pH values tend to show minor variations and range from 7.5 to 9.0, while those from the new samples have values close to 6.5 (Umar, Aziz, & Yusoff, 2010). The pH of the leachate can have a significant effect on the stabilization of the residues and the production of methane because methanogenic bacteria prefer optimum pH values between 6.8 and 7.2 and can be inhibited by acidic conditions (Abdallah & Kennedy, 2013).…”

“…One of the ways to improve biological degradation in old landfill cells is through recirculation of leachate, as these increases the humidity in the cell (Abdallah & Kennedy, 2013). When analyzing the management of the leachate generated in the studied landfill, it was verified that this practice was not adopted, but use of such a practice could potentially improve both the degradation rates and assist in the management of this effluent, thereby allowing for the material to be held for a longer time in the landfill and avoidance of high organic matter loads at the point of input to the STP.…”