Optimization of the Energy Consumption of a Carbon Capture and Sequestration Related Carbon Dioxide Compression Processes

It is likely that the future availability of energy from fossil fuels, such as natural gas, will be influenced by how efficiently the associated CO2 emissions can be mitigated using carbon capture and sequestration (CCS). In turn, understanding how CCS affects the efficient recovery of energy from fossil fuel reserves in different parts of the world requires data on how the performance of each part of a particular CCS scheme is affected by both technology specific parameters and location specific parameters, such as ambient temperature. This paper presents a study into how the energy consumption of an important element of all CCS schemes, the CO2 compression process, varies with compressor design, CO2 pipeline pressure, and cooling temperature. Post-combustion, pre-combustion, and oxyfuel capture scenarios are each considered. A range of optimization algorithms are used to ensure a consistent approach to optimization. The results show that energy consumption is minimized by compressor designs with multiple impellers per stage and carefully optimized stage pressure ratios. The results also form a performance map illustrating the energy consumption for CO2 compression processes that can be used in further study work and, in particular, CCS system models developed to study performance variation with ambient temperature.