Environmental and energetic analysis of coupling a biogas combined cycle power plant with carbon capture, organic Rankine cycles and CO2 utilization processes

Abstract

Greenhouse gas emissions from power plants that use fossil fuels cause a serious impact to the environment, for this reason the use of renewable energy technologies is an important alternative as a way of combatting climate change. The production of power via biomass is considered as a carbon neutral energy resource, but it is well known that the non-fossil CO2 emitted from this type of processes can also be captured. In order to do so, in this work it is proposed a match between a Biogas combined cycle power plant and postcombustion carbon capture process, to capture the CO2 produced by the biogas combustion, and also it considered a match with an organic Rankine cycle that uses the wasted energy of the combustion gases. Additionally, it is considered that the captured carbon is used to produce some value-added chemicals and fuels. Environmental and energetic evaluations were carried out for the coupling of those technologies. The implementation of the carbon capture plant, results on a diminution of the 87% of the emission of the combined cycle power plant. The life cycle analysis results show that the study case of Syngas production via dry reforming of methane, presents the lower global warming potential (0.088 CO2-eq kg/kg) and it was also found that the global warming potential has a reduction with the help of the mass integration between the different alternatives of CO2 utilization. Finally, it was found an annual reduction of 0.055 CO2-eq t for the system with mass integration compared with the cases without mass integration.