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Integrating bioenergy and carbon capture and storage (BECCS) presents a great opportunity for power production with negative global CO 2 emissions. This work explores a novel synergetic system that integrates membranes, partial biomass oxycombustion and the calcium looping (CaL) process. Polymeric membranes generate oxygen-enriched air (OEA) with an O 2 concentration of 39%v/v, which is used for partial oxycombustion of biomass waste. The CO 2 -enriched flue gas evolves from the waste-to-energy plant to the CaL unit, where CO 2 concentration is increased up to 90–95%v/v, ready for purification and sequestration. Compared to only oxycombustion systems, the proposed concept presents fewer technological challenges in retrofitting boilers to waste-to-energy plants. Moreover, this new approach is highly efficient as integrating membranes to produce OEA instead of cryogenic distillation systems significantly reduces energy consumption. A novel integration concept is modelled to evaluate the whole process efficiency and the effect of key parameters on the system performance, such as the temperature of the reactors, the membrane surface area, and the partial oxy-combustion degree. The results show that the so-called mOxy-CaL system has an energy consumption associated with CO 2 capture below 4 MJ/kg CO 2 (a 31% lower than that for a conventional CaL process), with a higher CO 2 capture efficiency than oxycombustion and the CaL process separately. On the other hand, the economic analysis shows a higher CO 2 capture cost for the novel configuration than for the typical CaL configuration due to the additional investment cost of the membrane system. Improvements in membrane performance by increasing its permeance and diminishing the required surface area would significantly reduce the economic cost of this novel integration. Using membranes with permeance over 400 GPU would boost the system's competitiveness. • A synergetic CO 2 capture process combining oxycombustion and CaL is proposed. • The so-called mOxy-CaL system has an energy consumption below 4 MJ/kg CO 2. • Membranes permeance limits the profitability of the process. [ABSTRACT FROM AUTHOR]

Partial oxycombustion using Oxygen-Enriched Air (OEA), produced by air-gas separation with polymeric membranes, combined synergistically with CO 2 capture technologies, can reduce the overall energy cost of CO 2 capture, and it is a potential alternative to conventional CO 2 capture technologies. An exhaustive review of polymeric membranes for this application is presented. The best membranes showed permeability values in the 450–25,100 barrer and selectivities higher than 3.6 for large-scale operations. These membranes can produce OEA with oxygen molar concentrations of up to 40% for retrofitting large-scale power plants (∼ 500 MWe) with partial oxycombustion. For OEA production, the polymeric membrane system is more efficient than cryogenic distillation since the specific power consumption of the former is 35.17 kWh/ton OEA. In comparison, that of the latter is 49.57 kWh/ton OEA. This work proposes that the OEA produced by the membranes feed a partial oxycombustion process integrated with calcium looping within a hybrid CO 2 capture system. The power consumption of the hybrid CO 2 capture system proposed here is 29.05% lower than in the case OEA is produced from cryogenic distillation, which justifies the potential interest in using polymeric membranes for OEA production. • Polymeric membranes for partial oxycombustion in CO 2 capture systems are evaluated. • Permeabilities of 500 to 25,100 barrer and selectivities from 2.7 to 5.1 are required in vacuum transmembrane pressures. • Polymeric membranes reduce by 29.05% the energy consumption (kWh/ton OEA). • A CO 2 capture system combining membranes, partial oxycombustion, and CaL is assessed. • SPECCA (MJ/kg CO 2) is reduced by 10.95% using membranes-based hybrid system. [ABSTRACT FROM AUTHOR]