D5.10: Configuration and preliminary performance of the CPU for two different CO2 target purities
This document provides the basis of design and a preliminary configuration with energy performance for the CO2 Purification Unit (CPU) of the full-scale integrated Calcium Looping cement plant. Two base cases have been defined, with two different outlet CO2 specifications: ‘moderate purity’ and ‘high purity’.
As a consequence, two different CPU configurations, able to achieve the two different purities, have been defined. They are based on the following steps: dust abatement, first compression, dehydration, cryogenic CO2 purification via partial condensation at low-temperatures and final compression to dense-phase conditions. The two CPUs differ for the cryogenic separation unit, which is based on (i) a double flash Vapor-Liquid separation process for the ‘moderate purity’ case, and on (ii) a more complex process integrating phase separation with a stripping column for the ‘high purity’ case.
Aspen Plus process simulations show that the ‘moderate purity’ case exhibits a specific electric consumption of 459 kJ/kg CO2 and a CO2 recovery of 97.6 %. For the ‘high purity’ case, the specific electric consumption rises to 499 kJ/kg CO2, while the CO2 recovery drops to 93.6 %.