Simultaneous Compression and Absorption for Energy-Efficient Dissolution of Gases in Liquid

In this study, a novel approach for energy-efficient dissolution of gases in liquid is presented, which significantly reduces the compression work. The core of the one-step process is the simultaneous operation of compression and absorption. The liquid was injected into a cylinder filled with the gas, while a piston compressed the mixture during the injection time. The solubility increases with increasing system pressure, so that the compression work of the gas phase is permanently reduced on the one hand by the permanent reduction of the gas volume and on the other hand by the nearly isothermal compression process. The approach is demonstrated in this study using liquid H2O and gaseous CO2 compressed up to 10 bar. The theoretical energy savings of the novel process compared to the conventional two-stage process is 41.2 % for the selected fluids. A maximum energy saving of 40.8 % was demonstrated in the experiments. The results also show that the energy saving depends on the curve of the piston speed and the injection time.