Steam bottoming cycles offshore - Challenges and possibilities

  • Lars O. Nord Norwegian University of Science and Technology, Trondheim, Norway
  • Olav Bolland Norwegian University of Science and Technology, Trondheim, Norway

Abstract

This paper addresses the challenges and possibilities related to offshore steam bottoming cycles with a special focus on once-through heat recovery steam generators (HRSGs). The main focus of the paper is to investigate the compromise between weight and efficiency of the HRSG by process simulation. The cost per installed kg of equipment is high offshore. Therefore, any bottoming cycle, applied to the back-end of the gas turbine, needs to be compact, yet sufficiently efficient. Important parameters to make the HRSG compact were the number of steam pressure levels, the HRSG technology, the flue gas pressure drop in the HRSG, and the pinch-point temperature difference. While selecting the parameters as a compromise between weight and efficiency, the combined cycle net plant efficiency was found to be approximately 50% with a power output of 43 MW. The steam turbine gross power output was 11 MW or about 25% of the total combined cycle plant gross power output. These results were compared to an onshore reference plant model which utilized the same type of aeroderivative gas turbine. The weight of the offshore once-through HRSG was about one third of the onshore HRSG. The net plant efficiency was 3%-points lower for the offshore system.

Author Biographies

Lars O. Nord, Norwegian University of Science and Technology, Trondheim, Norway
Department of Energy and Process Engineering
Olav Bolland, Norwegian University of Science and Technology, Trondheim, Norway
Department of Energy and Process Engineering

References

Alvarez, H., 2006. Energiteknik, 3rd Edition. Vol. 2. Stu- dentlitteratur AB, Lund, Sweden, ISBN 9789144045108.
Brady, M. F., 2001. Design aspects of once through systems for heat recovery steam generators for base load and cyclic operation. Materials at High Temperatures 18 (4), 223–
229.

De Meo, R., D’Ercole, M., Russo, A., Gamberi, F., Gravame, F., Mucz, D., 2008. PGT25+G4 gas turbine development, validation and operating experience. Vol. 7 of Proceedings of ASME Turbo Expo. pp. 529–538, paper no. GT2008-
50159.

Dumont, M. N., Heyen, G., 2004. Mathematical modelling and design of an advanced once-through heat recovery steam generator. Computers and Chemical Engineering
28 (5), 651–660.

Farmer, R., 1998. North Sea platforms are converting mech drives to comb cycle operation. Gas Turbine World November-December, 12–16.

Franke, J., Lenk, U., Taud, R., Klauke, F., 2000. Advanced Benson HRSG makes a successful debut. Modern Power Systems 20 (7), 33–35.

Gabrielli, F., Schwevers, H., 2008. Design factors and water chemistry practices - supercritical power cycles. In: Span, R., Weber, I. (Eds.), 15th International Conference on the Properties of Water and Steam. VDI - The Association of German Engineers; GET - Society for Energy Technology, Dusseldorf, Germany, pp. 1–15.

IAPWS, 2010. Technical guidance document: Volatile treat- ments for the steam-water circuits of fossil and combined cycle/HRSG power plants. International Association for the Properties of Water and Steam, http://www.iapws. org.

Kloster, P., 1999. Energy optimization on offshore installa- tions with emphasis on offshore combined cycle plants. In: Offshore Europe Conference; Aberdeen, Scotland. Society of Petroleum Engineers Inc., paper no. SPE 56964.

Lloyd, S. A., 1991. Co-generation in offshore process plat- forms. In: 5th International Symposium and Exposition on Gas Turbines in Cogeneration, Repowering, and Peak- Load Power Generation; Budapest, Hungary. ASME IGTI Vol. 6, pp. 281–286.

Mucino, M., Li, Y. G., Ojile, J., Newby, M., 2007. Ad- vanced performance modelling of a single and double pres- sure once through steam generator. Vol. 3 of Proceedings of ASME Turbo Expo. pp. 663–673, paper no. GT2007-
27505.

Ngoma, G. D., Sadiki, A., Wamkeue, R., 2003. Efficient ap- proach in modelling and simulation of dual pressure once- through heat recovery steam generator. Vol. 7 of Proceed- ings of the Seventh IASTED International Conference - Power and Energy Systems. pp. 218–223.

Starr, F., 2003. Background to the design of HRSG systems and implications for CCGT plant cycling. Power Plant: Operation Maintenance and Materials Issues 2 (1), 1–17. The Babcock & Wilcox Company, 2005. Steam/its genera- tion and use, 41st Edition. The Babcock & Wilcox Com-
pany, Barberton, Ohio, USA, ISBN 0963457012. Thermoflow, 2011. GT PRO and PEACE Version 21. Ther-
moflow Inc.

Wagner, W., Cooper, J. R., Dittmann, A., Kijima, J., Kret- zschmar, H. J., Kruse, A., Mares, R., Oguchi, K., Sato, H., Stocker, I., Sifner, O., Takaishi, Y., Tanishita, I., Trubenbach, J., Willkommen, T., 2000. The IAPWS in- dustrial formulation 1997 for the thermodynamic proper- ties of water and steam. Journal of Engineering for Gas Turbines and Power 122 (1), 150–180.
Published
2012-10-01
How to Cite
NORD, Lars O.; BOLLAND, Olav. Steam bottoming cycles offshore - Challenges and possibilities. Journal of Power Technologies, [S.l.], v. 92, n. 3, p. 201--207, oct. 2012. ISSN 2083-4195. Available at: <https://papers.itc.pw.edu.pl/index.php/JPT/article/view/346>. Date accessed: 28 mar. 2024.
Section
Power Plant

Keywords

once-through; Rankine cycle; combined cycle; process simulation

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