Conceptual Design Of A Mid-Sized Semi-Closed Oxy-Fuel Combustion Combined Cycle
Paper in proceedings, 2011

This paper presents the study of a mid-sized semi-closed oxy-fuel combustion combined cycle (SCOC-CC) with net power output around 108 MW. The paper describes not only the power balance and the performance of the SCOC-CC, but also the conceptual design of the SCOC turbine and compressor. A model has been built in the commercial heat and mass balance code IPSEpro to estimate the efficiency of semi-closed dual-pressure oxy-fuel combustion combined cycle using natural gas as a fuel. In order to obtain the real physical properties of the working fluids in IPSEpro, the code was linked to the NIST Reference Fluid Thermodynamic and Transport Properties Database (REFPROP). The oxy-fuel turbine was modeled with the in-house Lund University package LUAX-T. Important features such as stage loading, loss modeling, cooling and geometric features were included to generate more accurate results. The oxy-fuel compressor has been modeled using a Chalmers university in-house tool for conceptual design of axial compressors. The conceptual design of the SCOC-CC process has a net efficiency of 47 %. The air separation unit and CO2 compression reduce the cycle efficiency by 10 and 2 percentage points, respectively. A single-shaft configuration was selected for the gas turbine simplicity. The rotational speed chosen was 5200 rpm and the turbine was designed with four stages. All stage preliminary design parameters are within ranges of established industrial axial turbine design limits. The main issue is the turbine exit Mach number; the stage must be lightly loaded in terms of pressure ratio to maintain the exit Mach number below 0.6. The compressor is designed with 18 stages. The current value of the product of the annulus area and the blade rotational speed squared (AN2) was calculated and found to be 40*10^6.

CO2.

gas turbine

mid-sized dual pressure combined cycle

SCOC-CC

Oxy fuel

Author

Majed Sammak

Lund University

Klas Jonshagen

Lund University

Marcus Thern

Lund University

Magnus Genrup

Lund University

Egill Maron Thorbergsson

Chalmers, Applied Mechanics, Fluid Dynamics

Tomas Grönstedt

Chalmers, Applied Mechanics, Fluid Dynamics

Adrian Dahlquist

Siemens industrial turbomachinery

Proceedings of the ASME Turbo Expo 2011: Power for Land, Sea and Air, 2011, Vancouver, Canada

Vol. 4 253-261

Driving Forces

Sustainable development

Areas of Advance

Energy

Subject Categories

Fluid Mechanics and Acoustics

DOI

10.1115/GT2011-46299

More information

Latest update

5/24/2019