PROCESSES AND SYSTEMS FOR REMOVING ACID GAS FROM SYNGAS

摘要

Embodiments of processes and systems for removing acid gas including carbon dioxide from syngas are provided. The process comprises the steps of separating the acid gas from the syngas using an absorbent solvent to form a treated syngas stream and a carbon dioxide-rich solvent stream. Carbon dioxide and residual gas is flashed from the carbon dioxide-rich solvent stream to form a carbon dioxide-rich flash stream. The carbon dioxide-rich flash stream is compressed to a predetermined high pressure. The carbon dioxide-rich flash stream is cooled and expanded to a predetermined low temperature and pressure to form a cooled expanded carbon dioxide-rich flash stream. The cooled expanded carbon dioxide-rich flash stream is fractionated to form a carbon dioxide-ultra-rich product stream and a residual gas stream.