Feasibility of CaO/CuO/NiO sorption-enhanced steam methane reforming integrated with solid-oxide fuel cell for near-zero-CO2 emissions cogeneration system

Abstract

In this article, a process for sorption-enhanced steam methane reforming in an adiabatic fixedbed reactor coupled with a solid oxide fuel cell (SOFC) is evaluated using a 1D numerical reactor model combined with a simplified fuel cell simulation. A novel material comprising CaO/CuO/Al2O3(NiO) pellets is considered. Three operating stages are considered in the proposed system, namely (i) CaO carbonation/reforming, (ii) Cu and Ni oxidation, and (iii) CaCO3 calcination/CuO and NiO reduction. The operating conditions that enable cyclic operation of these stages and the strategy needed to switch between each stage are evaluated. Under the adopted control strategy, methane conversion was about 95%, whilst H2 yield and purity were around 3.2 molH2 molCH4-1 and 90%, respectively. Moreover, a concentrated CO2 stream ready for storage was obtained. By using a portion of the produced H2 to make the process self-sufficient from an energy standpoint, an equivalent H2 yield and a reforming efficiency of about 2.8 molH2 molCH4-1 and 84% were achieved, respectively. With respect to SOFC integration, net power and thermal energy generation of around 11 kW and 6 kW, respectively, can be achieved. With respect to the chemical energy of the inlet methane, the net electrical and thermal efficiencies of the considered process are 56% and 30%, respectively, i.e., the overall efficiency of the entire system is 86%. The proposed cogeneration system showed better thermodynamic, environmental and economic performances than those of conventional systems, with an investment pay-back period of 2.2 years in the worst-case scenario. The levelised cost of electricity, of heat and total power were about 0.096 € kWh-1 , 0.19 € kWh-1 , and 0.065 € kWh-1 , respectively, while the CO2 emissions were avoided at no cost.

Feasibility analysis of a combined chemical looping combustion and renewable-energy-based methane production system for CO2 capture and utilization

“…However, it should be noted that, depending on the type of catalyst, feed gas composition, and operating conditions, carbon deposition on the supported catalyst can occur (according to Boudouard reaction 2CO C+CO 2 ); to avoid solid carbon formation, the temperature should be kept high or CO 2 and/or H 2 O has to be added to the feed (e.g. [16]). Under the current assumption that H 2 and CO 2 are stoichiometrically fed to the methanation unit, no carbon deposition occurs.…”

Technoeconomic Analysis of a Fixed Bed System for Single/Two–Stage Chemical Looping Combustion

“…where TCC are the total capital costs of the reactor network, FCF is the fixed charged factor, FOM are the fixed operating and maintenance costs, CF is the capacity factor of the plant, set at 0.85, [34,37] 8760 is the average number of hours in a year, VOM are the variable operating and maintenance costs, and SFC is the specific fuel cost, set equal to 19.1 € MW À1 h À1 (5.3 € GJ À1 ). [38] TCC was assessed by estimating the costs of the main components of the reactor network. FCF was estimated as…”

“…The reference cost of the inert material was instead set at 1000 € ton À1 . [38] The cost of the compressors was estimated as [39] C comp ½$ ¼ 39.5W comp 0. where W comp is the mass flow rate of the stream fed to the compressor, η comp is the efficiency of the compressor, and p out,comp and p in,comp are the outlet and inlet pressure of the compressor, respectively. The capital cost of the compressor was updated to present value by referring to the chemical engineering plant cost index for the year 2019.…”

Embedding Ni in Ni–Al Mixed-Metal Alkoxide for the Synthesis of Efficient Coking Resistant Ni–CaO-Based Catalyst-Sorbent Bifunctional Materials for Sorption-Enhanced Steam Reforming of Glycerol

“…Therefore, about 32 Gt of CO 2 was released to the atmosphere. As the global energy demand is growing, it is expected that the CO 2 emissions will increase to about 48 Gt/year by 2040. , Hence, major efforts are needed to meet the emissions reduction targets. In this context, “hydrogen economy” has been acknowledged as an emission-free technology.…”