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Leachate is a liquid produced by the decomposition of organic and inorganic waste in landfills and can pollute soil and groundwater, as well as pose a risk to public health if not properly managed. In this work, the methanogenic potential of the leachate generated in the landfill of the Intermunicipal Consortium of Pontal do Paranapanema was evaluated to estimate the volume of biomethane produced from the leachate. Subsequently, an environmental and economic assessment was made of the potential replacement of diesel used by the waste collection fleets of the member municipalities of the consortium with biomethane. The results indicate that biomethane would supply 23.2% of the demand for fossil fuel, providing savings and a reduction in the amount of CO2 emitted into the atmosphere. This study demonstrated that the biomethane generated from landfill leachate can be an important source of renewable energy generation for the Intermunicipal Consortium of Pontal do Paranapanema to replace the diesel used by the waste collection fleets with biomethane. [ABSTRACT FROM AUTHOR]

Introduction: the production of biogas is a sustainable alternative for the energy use of organic waste. This investigation presents the study and modeling of biogas production, generated by the co-digestion of livestock excreta and cheese whey. Method: Anaerobic Digestion (DA) experiments were carried out, using hermetic reactors, at room temperature monitored for 75 consecutive days based on the biochemical methane potential (BMP) method. The logistic models were used: exponential maximum growth, Gompertz and Richards modified to represent the kinetics of the methane production phenomenon. Results and discussions: the maximum methane production rate, the duration of the lag phase, and the accumulated methane production potential were determined. The residual sum of squares and the correlation coefficient were compared to identify the mathematical model that best describes the phenomenon. It was found that there is a potential for the generation of biogas and the use of the residues experienced in this work in co-digestion. Conclusions: experimentation and mathematical modeling allowed to describe the phenomenon of biogas production, with residues from the dairy industry and livestock systems. The results of the research show the potential to incentivize energy production in the regional agricultural sector, based on DA technology, taking advantage of the dairy industry waste under the concept of circular economy. [ABSTRACT FROM AUTHOR]

The final disposal sites for urban solid waste generate biogas, a product of the decomposition of organic matter disposed in it. Biogas rich in methane contributes to the greenhouse effect, therefore its recovery and use represent a business opportunity thanks to the benefits obtained through the clean development mechanism (CDM), stipulated in the Kyoto Protocol; as in the Paris Agreement where one of the binding tools are the sustainable development mechanisms, which continue to pave the way for the use of technologies that promote sustainable development in this area of biogas, for its control and subsequent use. which started with its predecessors the CDM. The scope of this study is to identify through a Systematic Literature Review the institutional situational framework between the periods after the Kyoto Protocol and the Paris Agreement, relative to the integral management of DSU and public policies to control the biogas from of this type of waste in Venezuela and contrast it with the rest of the world. The formulation of the aforementioned mechanisms, framed in public policies, such as tax incentives, creation of laws and policies that allow stimulating environmental investment in the adoption of clean technologies, allow the reduction and control of biogas emissions from the waste sector; They are also appropriate tools to convert uncontrolled final disposal sites in Venezuela into controlled sanitary landfills, thus reducing greenhouse gases from this sector. [ABSTRACT FROM AUTHOR]

This work presents research involving a pilot scale biogas compression system. In an attempt to make it easier to use and commercialize this biofuel, the study looks at its treatment, filtration and compression. The process studied enables storage, transport and sale of biogas. Without a compression system, the use of biogas is restricted to the production site. On the other hand, when biogas is filtered and compressed there are several different applications in homes, industry, automotive vehicles, and other cases. The system is composed of a sector for filtration, reduction of noncombustible gases such as carbon dioxide and a compression sector for filling cylinders. The process uses biogas itself as fuel for motors and equipment. Different levels of pressure were established to use in various applications. In the experiment, data on compression, flow and composition of the biogas were obtained. [ABSTRACT FROM AUTHOR]

Available technologies that have been implemented for biogas purification for its use in power generation are summarized and analyzed. It is known that biogas may contain some impurities and trace elements that must be removed before its use as energy source. Traditional technologies for biogas purification are based primarily on the use of physical and chemical methods, which, besides generating secondary pollutants, often have a high cost. As an alternative, biogas purification through biological processes using microorganisms has become attractive. The microorganisms can remove substances considered pollutants; especially they can remove hydrogen sulfide. It is concluded that the method is cost effective with low energy inputs and harmless to the environment and human health. [ABSTRACT FROM AUTHOR]

Introduction. Urban societies produce solid and liquid waste in a growing quantity. For a long time, several alternatives have been used for managing such wastes in an integrated way, but those alternatives are now out fashioned. Objective. To compare two anaerobic digestion systems with and without separation of the hydrolytic phase in a laboratory scale, for the biomethanization of the organic fraction of urban solid waste (FORSU, in Spanish) and domestic waste water (ARD in Spanish), evaluating its performance under efficiency for eliminating organic matter and methane generation terms. Materials and methods. Two systems of anaerobic methanization were compared in a laboratory scale. Mesophilic, the first one, was an anaerobic reactor of ascending flow (R1) and the second was a system separated into two phases: Hydrolytic reactor of ascending flow (R2) and an anaerobic ascending flow reactor of sludge blanket (UASB). The carbon source used was the organic fraction of urban solid waste and domestic urban waste water. Both systems were evaluated during 120 days. Results. For R1, the maximum organic charge speed (VCO in Spanish) was 4,7 Kg, chemical oxygen demand (COD)/m³-d, time of hydraulic retention (HRT), 24 hours, pH 7,01 at 7,77 to obtain a methane performance of 0,17 L/g initial volatile solid. On the other hand, the R2+UASB, the maximum organic charge speed to depurate was 17 Kg chemical oxygen demand m³-d, the HRT for R2 was 24 hours and for the UASB was 12 hours, with a pH for R2 between 4,92 and 5,34, and for the UASB, between 6,60 and 7,80, obtaining a methane performance of 0,29 L/g initial volatile solid. The highest production of volatile fatty acids was registered in R2 with 46,96g/L expressed in acetic acid (HAc). The elimination rate of chemical oxygen demand in R1 was 91% and the elimination rate of volatile solid was 92%. For R2 +UASB the chemical oxygen demand eliminated was 96% and the volatile solid was 97%. Conclusion. Applying a hydrolytic reactor to an UASB allowed removing more organic charge and a better methane production. [ABSTRACT FROM AUTHOR]