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Sectoral adaptation strategies and resilience policies
Published in Walter Amedzro St-Hilaire, Agribusiness Economics, 2022
As we have seen, methanation, the process of producing synthetic methane from dihydrogen and carbon monoxide or carbon dioxide using a catalyst (catalytic methanation) or microorganisms (biological methanation), should not be confused with methanation. It can be encouraged with the introduction of calls for tender with additional remuneration, specifying that the incentive must vary according to the origin of the hydrogen: a distinction will therefore be made between clean hydrogen from renewable energies and so-called ‘low-carbon' hydrogen, i.e., that whose CO2 emissions level is below a given threshold, which makes it possible to include nuclear energy. It is necessary to have a cross-cutting approach to environmental issues, considering simultaneously the issues of energy, greenhouse gas emissions and carbon storage. Continue and amplify, at the international level, the ‘4 for 1,000' initiative.
Production of Substitute Natural Gas
Published in M.R. Riazi, David Chiaramonti, Biofuels Production and Processing Technology, 2017
Jürgen Karl, Michael Neubert, M.R. Riazi, David Chiaramonti
Common biogas plants convert biomass into a product gas that consists mainly of methane and carbon dioxide. They use biogenic and anthropogenic raw materials and residuals, for example, manure or corn silage. The microorganisms utilize short-chain fatty acids and hydrogen to produce methane at the end of the fermentative degradation of the biomass. Biological methanation converts carbon dioxide directly with hydrogen into methane via methanogenesis. A first concept feeds additional hydrogen directly into the fermenter of an existing biogas plant (in situ methanation). But most concepts comprise separate continuous stirred-tank reactors. Practical examples are power-to-gas projects from MicrobEnergy in Allendorf, Germany, or the BioCat Project developed by Electrochaea with an electrical power input of 1 MW in Denmark (Götz et al. 2016). The key challenge for the technology is to provide high gas–liquid surfaces that enable high mass transfer rates into the liquid phase of the substrate. New approaches suggest trickle-bed reactors (Burkhardt and Busch 2013, Rachbauer et al. 2016) to improve the mass transfer.
Storage of Fluctuating Renewable Energy
Published in Subhas K. Sikdar, Frank Princiotta, Advances in Carbon Management Technologies, 2021
The Power-to-Methane (PtM) technology combines the utilization of anthropogenic CO2 and H2 to produce gaseous methane. The electrolysis and methanation can be carried out in several ways: (1) alkaline electrolysis (AEL), (2) polymer electrolyte membranes (PEM) and (3) solid oxide electrolysis (SOEC). Concerning methanation, two different methodologies can be separated to reduce carbon dioxide: (1) chemical based catalytic methanation and (2) biological methanation using methanogen bacteria as a “biocatalyst”. The biological methanation is characterized by low operational temperature (30–60 °C) and atmospheric pressure. On the other hand, the reaction kinetics are slow, the operation is complex and the mass transfer is inadequate. In both ways, the methane is formed by the reaction of CO2 with H2 , which is known as the Sabatier reaction, Equation (2): CO2+4H2=CH4+2H2OΔH2980=−165.1kJmol−1
Alternatives of municipal solid wastes to energy for sustainable development. The case of Barranquilla (Colombia)
Published in International Journal of Sustainable Engineering, 2021
Alexis Sagastume Gutiérrez, Jorge M. Mendoza Fandiño, Juan J. Cabello Eras
Biological conversion technologies include anaerobic digestion, fermentation, and landfilling with gas recuperation. Anaerobic digestion (see Figure 4), also known as biological methanation, is a process catalysed by microbes in which a series of sequential microbial conversions, mineralise organic matter into biogas (i.e. through a series of oxidation-reduction reactions complex organic matter is converted to CH4 and CO2) (Angelidaki et al. 2019). To this end, MSW must be separated into organic and non-organic fractions, for which the main alternatives are the source and mechanical separation. In Colombia, where source separation of MSWs is not a common practice, only mechanical separation is possible.