Chemical and calcium looping systems : heat integration analysis for improvement the energy efficiency of various industrial processes

Abstract

Improvement of energy efficiency for key industrial sectors is of great importance today considering the potential economic and environmental benefits. The carbon capture, utilization and storage (CCUS) technologies are considered strategically important technological options for transition to a low carbon economy. In this respect the chemical & calcium looping systems are very promising methods to deliver both high energy efficiency and near zero CO2 emissions. This paper assesses the potential gains in term of energy efficiency for key illustrative fossil fuel-based industrial processes (e.g. combustion and gasification-based power plants, cement production plant, integrated steel mill, energy vector poly-generation systems etc.) by integration of chemical and calcium looping systems as carbon capture technologies. Two high temperature solid looping systems were evaluated in details: a chemical looping cycle using iron oxide as oxygen carrier and a calcium looping cycle using calcium-based sorbent. The carbon capture rate of all evaluated chemical & calcium looping concepts is almost total (>95%). As the detailed results show, the chemical & calcium looping systems exhibit superior energy efficiency, lower plant complexity and reduced CO2 emissions in comparison to the more commercially and technologically mature carbon capture options (e.g. based on chemical or physical gas-liquid absorption).