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Show BURNING LOW GRADE FUELS AND CONTROLLING NOX BY WATER INJECTION IN BBC GAS TURBINES BENNO BASLER ALEXANDER KOROSI BBC BROWN BOVERI & CO. AG STONE & WEBSTER ENGINEERING CORPORATION CH-5401 BADEN, SWITZERLAND BOSTON, MASS. 02107, USA I. INTRODUCTION The purpose of this paper is to highlight the experience record of the BBC heavy duty stationary gas turbines in the combustion of unconventional fuels. The specific examples used in demonstrating the fuel flexibility of these machines were chosen from two sources. In the first group, information is offered from commercial plant operations, while in the second group results of full scale combustion studies are discussed. The data are presented over a broad spectrum of nontraditional fuels. The range extends from the present-day low heating value blast furnace gases and crude oils to the alternative fuels of the future, derived from shale oil and coal liquefaction. Typical operation problems encountered with the use of these low grade fuels such as fouling, blade corrosion and incrustration, and increased heat load to the combustor walls, along with the countermeasures taken, will be briefly reviewed. Environmental concerns related to potential increases in emissions due to adverse fuel properties were also addressed and evaluated for most fuels, and in brief summary, the results are as follows: Differences in the individual pollutant levels for CO, N02, UHC, PNA (unburned and polyaromatic hydrocarbons) were minor and nonspecific with varying fuels. For all cases the absolute level of these contaminants remained low in the important operating load regions of the gas turbine. NO emissions increased, as expected, by increasing flame temperatures and 1.4.1 |