K-102A/B CO compressor
K-103A/B Natural gas compressor
E-101 CO product/ NG exchanger
E-105 CO product exchanger
Residue gas
TC
EC-102 OVHD condense
LC
CO to others
EC-102 CO product chiller
V-101 CO re ux drum
TC
PA-101 refrigeration package
Purge
LC
20
E-104 natural gas exchanger
E-103 CO fractionator reboiler
TC
P-101A/B re ux pump
TC
C-101 CO fractionator
E-101 cold box exchanger
JT-101
EC-101 chiller
LC
K-101A/B Feed compressor
LC
P-102A/B CO pump
Residue gas
Figure 7 CO 2 liquefaction process flow diagram
reduces the chiller to a pressure at which it can be condensed in an air cooler. The design temperature of the liquid refrigerant leaving the condenser is defined. This temperature, however, will be lower during operation at low ambient air temperatures. Lowering the condensing temperature results in a lower compressor discharge pressure, which reduces the compressor’s power requirement. The refrigerant mass flow is also reduced, since colder refrigerant is available for the process. Figure 7 presents the process flow diagram for CO 2 liquefaction. Conclusion The traditional scheme of CO 2 removal is to use the amine unit like activated MDEA or similar solvents. In most cases, the most significant disadvantages are very high circulation of the solvent, which would increase the capital cost
the liquid and vapour to separate. ➏ The cooled warm stream leaves the BAHX and vessel. ➐ The cold stream vapour exits the vessel through the outlet nozzles while the liquid falls back to be recirculated. ➑ A manway is provided in the vessel shell. ➒ Mercury tolerant construction – under certain conditions, liquid elemental mercury can have a detrimental effect on unprotected BAHX. The complete configuration of the CO 2 liquefaction is straightforward and consists of a CO 2 fractionation column with the associates’ heat exchangers. The chilling system consists of an air cooler, a pre-chiller that utilises propane refrigerant at the chiller, evaporating propane at lower pressure. Propane refrigerant vaporised in the pre-chiller and a gas turbine-driven centrifugal compressor
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