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The purpose of this research is to investigate a variety of approaches to the conversion of biomass, with a particular emphasis on employing anaerobic digestion and biogas upgrading systems. An analysis of the existing technologies is performed, with a focus on highlighting the benefits and downsides of each alternative. In order to assess the effects of nitrogen and oxygen in the biogas on the cryogenic distillation process, an investigation is being carried out. The findings suggest that the presence of these two chemical species in the biogas necessitates the final condensation of methane in order to separate them from one another. In conclusion, a qualitative economic analysis is carried out in order to ascertain the most cost-effective strategy that can be implemented in a typical Italian installation. According to the assumptions that were used, membrane separation is the solution that offers the most cost-effectiveness. [ABSTRACT FROM AUTHOR]

This work investigates the performance of a fluidized-bed membrane reactor for pure hydrogen production. A techno-economic assessment of a plant with the production capacity of 100 kg H2 /day was carried out, evaluating the optimum design of the system in terms of reactor size (diameter and number of membranes) and operating pressures. Starting from a biomass source, hydrogen production through autothermal reforming of two different feedstock, biogas and biomethane, is compared. Results in terms of efficiency indicates that biomethane outperforms biogas as feedstock for the system, both from the reactor (97.4% vs 97.0%) and the overall system efficiency (63.7% vs 62.7%) point of views. Nevertheless, looking at the final LCOH, the additional cost of biomethane leads to a higher cost of the hydrogen produced (4.62 €/kg H2@20 bar vs 4.39 €/kg H2@20 bar), indicating that at the current price biogas is the more convenient choice. • Small-scale hydrogen production process intensification with membrane reactors. • Biogas and biomethane autothermal reforming are compared. • Detailed model of the fluidized bed membrane reactor and of the overall process. • Optimization of reactor and system performance and of levelized cost of hydrogen. [ABSTRACT FROM AUTHOR]

This paper investigates the potentiality of membrane reactor for green hydrogen production from raw biogas. The assessment is carried out both from thermodynamic and economic point of view to outline the advantages of the innovative technology with respect to the conventional one based on reforming, water gas shift and pressure swing adsorption unit. Both biogas produced by landfill and anaerobic digestion are considered to evaluate the impact of biogas composition on system design. BIONICO system model is implemented in Aspen Plus and Aspen Custom Modeler to perform respectively the balance of plant with thermal integration and a detailed fluidized bed membrane reactor design. Two permeate side configurations, sweep gas and vacuum pump, were modelled and compared. The adoption of membrane reactor increases the system efficiency by more than 20% points with respect to reference cases. Focusing on the economic results, hydrogen production cost show lower value respect to the reference cases (4 €/kg H2 vs 4.2 €/kg H2 ) at the same hydrogen delivery pressure of 20 bar. Between the landfill and anaerobic digestion cases, the latter has the lower costs as consequence of the higher methane content. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of the support material and its thickness on the hydrogen flux in Palladium membranes in the presence of sweep gas in fluidized bed membrane reactors. The analysis is performed considering both ceramic and metallic supports with different properties. In general, ceramic supports are cheaper but suffer sealing problems, while metallic ones are more expensive but with much less sealing problems. Firstly, a preliminary analysis is performed to assess the impact of the support in the permeation flux, which shows that the membrane permeance can be halved when the H2 diffusion through the support is considered. The most relevant parameter which affects the permeation is the porosity over tortuosity ratio of the porous support. Afterward, the different supports are compared from an economic point of view when applied to a membrane reactor designed for 100 kg/day of hydrogen, using biogas as feedstock. The stainless steel supports have lower impact on the hydrogen permeation so the required membrane surface area is 2.6 m2 compared to 3.6 m2 of the best ceramic support. This ends up as 5.6 €/kg H2@20bar and 6.6 €/kg H2@700bar for the best stainless steel support, which is 3% lower than the price calculated for the best ceramic support. [ABSTRACT FROM AUTHOR]

This work investigates the environmental and economic performances of a membrane reactor for hydrogen production from raw biogas. Potential benefits of the innovative technology are compared against reference hydrogen production processes based on steam (or autothermal) reforming, water gas shift reactors and a pressure swing adsorption unit. Both biogas produced by landfill and anaerobic digestion are considered to evaluate the impact of biogas composition. Starting from the thermodynamic results, the environmental analysis is carried out using environmental Life cycle assessment (LCA). Results show that the adoption of the membrane reactor increases the system efficiency by more than 20 percentage points with respect to the reference cases. LCA analysis shows that the innovative BIONICO system performs better than reference systems when biogas becomes a limiting factor for hydrogen production to satisfy market demand, as a higher biogas conversion efficiency can potentially substitute more hydrogen produced by fossil fuels (natural gas). However, when biogas is not a limiting factor for hydrogen production, the innovative system can perform either similar or worse than reference systems, as in this case impacts are largely dominated by grid electric energy demand and component use rather than conversion efficiency. Focusing on the economic results, hydrogen production cost shows lower value with respect to the reference cases (4 €/kgH2 vs 4.2 €/kgH2) at the same hydrogen delivery pressure of 20 bar. Between landfill and anaerobic digestion cases, the latter has the lower costs as a consequence of the higher methane content. [ABSTRACT FROM AUTHOR]