COMPRESSOR PUMP UNIT FOR CO2 LIQUIDATION AND SUPPLY IT FOR CARBAMIDE SYNTHESIS

  • G.K. Lavrenchenko LLC "Institute of Low Temperature Energy Technology", Odesa https://orcid.org/0000-0002-8239-7587
  • B.H. Hrudka Odessa National Academy of Food Technologies, Institute of Cold, Cryotechnologies and Environmental Energy named after V.S. Martynovskiy, Odesa https://orcid.org/0000-0003-1200-5442
Keywords: gaseous and liquid carbon dioxide, ammonia, urea, compressor-pumping unit, supercritical pressure, gas compression, thermodynamic analysis, efficiency

Abstract

Carbon dioxide, as well as ammonia, are widely used in large-scale chemistry for the production of urea. Currently, the most common technology for producing carmabide is according to which liquid NH3 is pumped into the synthesis column by a pump at a pressure of 15 MPa, and gaseous CO2 is supplied by a compressor with the same pressure as ammonia. Gaseous CO2 is compressed in a multi-stage compressor to a pressure of 15 MPa before it enters the urea synthesis unit, in which it reacts with ammonia. The specific energy consumption for compressing carbon dioxide in a compressor unit is 0.13 kWh/kg. Reducing energy for producing CO2 and also urea can be achieved when it is possible to supply carbon dioxide in liquid form under a pressure of 15 MPa to the urea synthesis column. The analysis showed that to solve this problem it is necessary to implement two processes: compression to 1.8–3.0 MPa, and then cooling and liquefaction of gaseous CO2 due to the cold of liquid ammonia. Liquefied CO2 can then be pumped to the urea column. In order to introduce carbamide into production, a new carbon dioxide compressor and pumping unit has been created. The installation scheme for compressing CO2 to a pressure of 15 MPa and its subsequent supply to the production of urea is given. A cold liquid ammonia stream with an initial temperature of –30 °C is used as a source of cold in the installation. The performance and power consumption of the compressor unit depend on the compression pressure of CO2. After the CO2 is compressed to 1.8 MPa, it is possible to cool 2.3 t/h of carbon dioxide with cold liquid ammonia and then direct it to the synthesis of urea using a pump under a pressure of 15 MPa. The specific energy consumption in the installation will be 0.1 kWh/kg. When CO2 is compressed up to 3 MPa, the plant capacity is 8.78 t/h, and the unit costs are 0,108 kWh/kg. Urea production in this case may increase from 1400 to 1680 t/day. Ref. 5, Fig. 3, Tab. 3.

Author Biographies

G.K. Lavrenchenko, LLC "Institute of Low Temperature Energy Technology", Odesa

Doctor of Technical Sciences, Professor

B.H. Hrudka, Odessa National Academy of Food Technologies, Institute of Cold, Cryotechnologies and Environmental Energy named after V.S. Martynovskiy, Odesa

Candidate of Technical Sciences

References

Lavrenchenko G.K., Kopytin A.V. [Energy Indicators of Various Processes of Compression of Carbon Dioxide to Supercritical Pressures]. Tekhnicheskie Gazy. [Industrial gases]. 2007. No. 1. pp. 31–36. (Rus.).

Pimenova T.F. [Production and Use of Dry Ice, Liquid and Gaseous Carbon Dioxide]. Moscow : Liohkaya i pishchevaya promyshlennost’, 1982. 208 p. (Rus.).

Alekseev A.P. et al. [Refrigeration equipment : Encyclopedic reference book. Book 2: The Use of Cold in Industry and Transport]. Moscow : Gostorgizdat, 1961. 575 p. (Rus.).

[Reference nitrogen]. Ed. Ye.Ya.Melnikov. Moscow : Khimiya, 1969. Vol. 2. 444 p. (Rus.).

Pat. 38275 Ukr., IPC F 25 B 1/00. [A compressor- pumping unit for liquefying carbon dioxide and supplying it with high pressure to the production of urea]. A.Yu.Fedchun, L.V.Lisovskiy, M.Ye.Yegrischin, G.K. Lavrenchenko, A.V.Kopytin. Publ. 25.12.2008, Bull. No.24. (Rus.)

Published
2020-09-20
How to Cite
Lavrenchenko, G., & Hrudka, B. (2020). COMPRESSOR PUMP UNIT FOR CO2 LIQUIDATION AND SUPPLY IT FOR CARBAMIDE SYNTHESIS. Energy Technologies & Resource Saving, (3), 41-49. https://doi.org/10.33070/etars.3.2020.04
Section
Raw material processing and resource saving