Liquefaction Pressure
From an electrical energy and cost perspective, there is a moderate effect on increasing the liquefaction pressure, as shown in Figure 3d and Figure S13a, respectively. This increase is primarily due to the increase in the size of the compressor used for liquefaction. The increase is slightly reduced as the liquefaction pressure approaches the separator operating pressure due to the necessity for less work in the recycle compressor. The primary effect of the choice of liquefaction pressure is on the temperature the liquefaction column requires for the 90% CO2 recovery condition set as a requirement for the process. These temperature effects across a wide range of separation performance (purity) conditions, are given in Figure S13c. This choice, therefore, has considerable effects on the design of the final heat exchanger network, as well as the ability of the plant to utilize the process’ available heat removal with a reasonable temperature approach.