Olav Bolland

In this paper, a gas-fired combined cycle power plant subjected to a pre-combustion CO₂ capture method has been analysed under different design conditions and different heat integration options. The power plant configuration includes the chemical looping reforming (CLR) of natural gas (NG), water gas shift (WGS) process, CO₂ capture and compression, and a hydrogen fuelled combined cycle to produce power. The process is denoted as a CLR-CC process. One of the main parameters that affects the performance of the process is the pressure for the CLR. The process is analysed at different design pressures for the CLR, i.e., 5, 10, 15, 18, 25 and 30 bar. It is observed that the net electrical efficiency increases with an increase in the design pressure in the CLR. Secondly, the type of steam generated from the cooling of process streams also effects the net electrical efficiency of the process. Out of the five different cases including the base case presented in this study, it is observed that the net electrical efficiency of CLR-CCs can be improved to 46.5% (lower heating value of NG basis) by producing high-pressure steam through heat recovery from the pre-combustion process streams and sending it to the Heat Recovery Steam Generator in the power plant.

Amine-functionalized mesoporous silica has attracted much attention as a promising chemical sorbent for capturing carbon dioxide. It has the combination of several features viz., high adsorption capacity, high selectivity toward CO₂, fast kinetics, mild conditions for desorption and should be stable under operating conditions. In this study, a chemical grafting route has been developed to synthesize mesoporous adsorbents with amines functionalization for CO₂ capture. The initial silylation step was achieved by grafting of different silane linkers (3-aminopropyl)-trimethoxysilane (APS) and 3-chloropropyl)-trimethoxysilane (CPS) via direct condensation and hydrolysis reaction. After silylation the CPS-supports was reacted with tris(2-aminoethyl)amine (TREN) to introduce the amine group to increase the adsorptive capabilities for these sorbents. The synthesized sorbents were characterized by N₂ adsorption/desorption, XRD, FTIR and HR-SEM. The adsorption capacities of the modified solid sorbents show a significant enhancement in their adsorption capacity by 3–4 times higher than that of the parent materials which indicate the affirmative impact of amines for CO₂ adsorption after grafting.