Abstract
Developing innovative power generation technologies with low fossil CO2 emissions is of paramount importance in modern society. Natural gas-based energy applications have the highest conversion efficiency, this fuel being considered the cleanest fossil fuel in terms of specific CO2 emissions. Carbon Capture, Utilisation and Storage (CCUS) technologies are seen as important future ways to reduce fossil CO2 emissions from the energy sector (heat and power production) as well as from other energy-intensive industrial applications (e.g. cement, petro-chemical and metallurgy sectors). Among various advanced carbon capture methods, Calcium Looping (CaL) option seems to be very promising in reducing both energy and cost penalty for CO2 capture. Potential utilisation of natural materials (limestone) and spent sorbent usage in construction sector are other attractive features of this carbon capture process.
The paper evaluates in details the Natural Gas Combined Cycle (NGCC) power plant concept with calcium looping cycle used for post-combustion CO2 capture. Plant operational aspects, mass and energy integration aspects, scale-up issues from current state of development (laboratory and pilot installations) to industrial scale and estimation of overall techno-economic performances are discussed within the paper. The plant design was modelled and simulated using process flow modelling software, the simulation results (the mass and energy balances) being used to assess the overall techno-economic and environmental indicators. For comparison reason, two benchmark NGCC power plant concepts were considered: a conventional NGCC power plant without carbon capture and a NGCC power plant with post- combustion capture using gas-liquid absorption (MDEA). The integrated techno-economic and environmental assessments show that calcium looping has significant advantages compared to benchmark cases such as higher plant energy efficiency, lower energy and cost penalties for CO2 capture and improved overall techno-economic and environmental performances.
