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Biogas is a renewable fuel and an energy source that can be applied in many different settings. It is defined as a combustible gas mixture produced by the anaerobic fermentation of biomass by bacteria and takes several days to form. In fact, the anaerobic digestion is a biological process, so valorizing organic matter, usually fatal, produces a renewable energy source and digestates that can be used as a fertilizer. Indeed, in the absence of oxygen (anaerobic digestion) and protected from light, organic matter is partially degraded by the combined action of several types of micro-organisms, a series of biological reactions leading to the formation of biogas composed of Carbon Dioxide (CO 2 ), Nitrogen N 2 , Hydrogen H 2 , Oxygen O 2 , Water vapor H 2 O, Hydroxide Sulfur H 2 S and the energy recoverable portion Methane CH 4 but very harmful to the environment, or even 22 times more harmful than CO 2 which is a greenhouse gas (GHG). Therefore, Waste-to-energy provides a solution for two problems: waste management and energy generation. This biogas opportunity has appeared as one of the most interesting applications to help many municipalities in different countries to produce clean energy and even to manage wastes. It can be applied on the wastes of the agricultural fields as well as in the farms, in the food industry or simply in the municipal landfills. Numerous biogas installations have been built all over the world. Initially, the main objective was to produce biogas to generate energy, but quickly the environment aspect has appeared as an additional reason to build such facilities. This study covers the sustainable development area in which we will estimate the potential to produce biogas starting from the annual organic wastes data given by the concerning ministries and organizations in Algeria.

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We present in this article an analysis of the impacts of the exhaust gas recirculation (EGR) and alternative fuels on HCCI combustion mode. The objective is to reduce the pollutant emissions below the levels of established pollution standards. The ANSYS CHEMKIN-Pro software and the combined chemical kinetics mechanism were used to perform simulations for a closed homogeneous reactor under conditions relevant to HCCI engines. The calculation process is based on one single-zone in the combustion chamber. Numerical simulation has proven the ability of the models adopted, which use the essential mechanisms of the fuel combustion process, to reproduce, among other things, the evolution of the formation of chemical species. This study showed that adding hydrogen (H2) to methane (CH4) is an interesting alternative fuel because it reduces ignition time. It was concluded that an increase of EGR rate conducts to a slower combustion process, lower temperatures, and the reduction of nitrogen oxide (NOX) emissions.