A techno-economic analysis of the application of continuous staged-combustion and flameless oxidation to the combustor design in gas turbines

Abstract

The impact of NO x reduction technologies upon a gas turbine power station has been investigated using the ECLIPSE process simulator. Technical, environmental and economic assessments were performed, based upon a model of the simple cycle gas turbine, fuelled by natural gas. The technologies assessed were: a) selective catalytic reduction (SCR); b) continuous staged air combustion (COSTAIR); and c) flameless oxidation method (FLOX). The SCR method produced a 90% reduction of NO x emissions, at an additional penalty to the electricity cost of 0.19–0.20 p/kWh, over the base case of simple cycle with standard combustor. The COSTAIR method reduced 80.4% of NO x emissions, at an additional electricity cost of 0.03–0.04 p/kWh, over the base case; but 0.16–0.17 p/kWh less than the SCR method at a slightly higher level of NO x emissions. The FLOX method generated 92.3% less of NO x emissions, at an additional electricity cost of 0.08–0.11 p/kWh, over the base case; but 0.09–0.11 p/kWh less than the SCR method at a lower level of NO x emissions. A sensitivity analysis of the Break-Even Selling Price (BESP) of electricity and the Specific Investment (SI) versus the cost of different burner systems shows that the SCR system had the highest values for BESP and SI; and the COSTAIR system had the lowest. The results show that the use of these non-standard burners could offer an effective method of reducing NO x emissions considerably for simple cycle gas turbine power plants with minimal effect on system capital cost and electricity selling price, and were also cheaper than using SCR.