Specifying Carbon Dioxide Centrifugal Compressor
- Manthan G. Desai (McDermott Middle East Incorporated)
- Document ID
- Society of Petroleum Engineers
- SPE Production & Operations
- Publication Date
- May 2018
- Document Type
- Journal Paper
- 313 - 319
- 2018.Society of Petroleum Engineers
- CO2 compression, Estimation, Centrifugal Compressors
- 2 in the last 30 days
- 173 since 2007
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This paper highlights the care to be taken by an engineer while specifying and selecting a centrifugal compressor for carbon dioxide (CO2) compression.
With the increase in the levels of CO2 in the atmosphere, there is an increase in the popularity of capturing CO2 emitted from the large source points such as fossil-fuel power plants, steel mills, cement plants, and others before its release to the atmosphere and storing it in geological formations [also used for enhanced oil recovery (EOR) where possible]. The compressors used to transport and store the CO2 at such depths need to compress the gas from atmospheric pressure to the pressures on the order of 200 bar or more.
The critical temperature of CO2 is only 31.1°C, so the CO2 is generally transported and stored in a supercritical state. The thermodynamic properties of supercritical CO2 are considerably different from those of the other real gases that are generally compressed. Further, to achieve this supercritical state, the critical point of CO2 is crossed somewhere in the compression stage. Near critical point, the ideal-gas law will not hold for CO2. Moreover, there is a reduction in the choke margin of the compressor caused by the reduction of the sound speed in CO2, particularly near the thermodynamic critical point. Also, the CO2 compressibility and specific heats are not linear near the critical pressure and temperature. The impurities in the CO2 will affect further the thermodynamic characteristics of the working fluid. Also, the water content in the CO2 makes it extremely corrosive.
Considering all the aspects mentioned previously, specifying the CO2 compressor correctly in terms of the equation of state (EOS) to be used, the interstage pressures and temperatures to be maintained, suggesting the number of impellers per stage to maintain the desired flow coefficient, metallurgy to be selected and scheme of compressor dry gas seals, and others becomes all the more important and is described in the paper.
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Benedict, M., Webb, G. B., and Rubin, L. C. 1940. An Empirical Equation for Thermodynamic Properties of Light Hydrocarbons and their Mixtures I. Methane, Ethane, Propane, and n-Butane. J. Chem. Phys. 8: 334–345. https://doi.org/10.1063/1.1750658.
Cengel, Y. A. and Boles, M. A. 2004. Thermodynamics, An Engineering Approach, fifth edition. New York: Mc-Graw Hill.
Compressor-Technology Sourcing Supplement. 2016.
Gas Processors Supplier Association (GPSA). 2012. GPSA Engineering Data Book, 13th edition. Tulsa: GPSA Midstream Suppliers.
Lapina, R. P. 1982. Estimating Centrifugal Compressor Performance–Process Compressor Technology Volume 1. Gulf Publishing Company.
Ludtke, K. H. 2004. Process Centrifugal Compressors: Basics, Function, Operation, Design, Application. Springer Publication.
Peng, D. Y. and Robinson, D. B. 1976. A New Two-Constant Equation of State. Ind. Eng. Chem. Fundamen 15 (1): 59–64. https://doi.org/10.1021/i160057a011.
Prausnitz, J. M., Poling B. E., and O’Connell, J. P. 2001. Properties of Gases and Liquids, fifth edition. New Delhi: McGraw-Hill Education.
Redlich, O. and Kwong, J. N. S. 1949. On the Thermodynamics of Solutions V. An Equation of State. Fugacities of Gaseous Solutions. Chem. Rev. 44 (1): 233–244. https://doi.org/10.1021/cr60137a013.
Soave, G. 1972. Equilibrium Constants From a Modified Redlich-Kwong Equation of State. Chrmical Engineering Science 27 (6): 1197–1203. https://doi.org/10.1016/0009-2509(72)80096-4.
Span, R. and Wagner, W. 1996. A New Equation of State for Carbon Dioxide Covering the Fluid Region From the Triple-point Temperature to 1100 K at Pressure up to 800 MPa. J. Phys. Chem. Ref. Data 25 (6): 1509–1596. https://doi.org/10.1063/1.555991.
Starling, K. E. 1973. Fluid Properties for Light Petroleum Systems. Houston: Gulf Publishing Company.